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Title: TESTING MICE AT RISK OF PANCREATIC CANCER FOR ALTERED PROTEIN PATHWAYS FOUND IN DIABETES.
Creator: Cheung, Henley, Altomare, Deborah A., University of Central Florida
Abstract / Description: Pancreatic cancer is nearly asymptomatic, which can result in extensive grow and even metastasis to other organs before detection. When diagnosed at a late stage, the survival rate is 3%. Early detection is therefore the key to treating pancreatic cancer. Diabetes was identified as a risk factor for the development of pancreatic cancer, but the mechanism remains unknown. In this project, the objective was to delineate a link between diabetes and pancreatic cancer by examining their shared...
Show morePancreatic cancer is nearly asymptomatic, which can result in extensive grow and even metastasis to other organs before detection. When diagnosed at a late stage, the survival rate is 3%. Early detection is therefore the key to treating pancreatic cancer. Diabetes was identified as a risk factor for the development of pancreatic cancer, but the mechanism remains unknown. In this project, the objective was to delineate a link between diabetes and pancreatic cancer by examining their shared protein signaling pathways. In a previous study, hyper-activation of AKT1 resulted in a pre-diabetic phenotype and also increased upregulation of downstream phosphorylated mTOR and phosphorylated p70S6 kinase. More recently, mice with mutations that hyper-activated AKT1 and KRAS showed a significantly higher blood glucose level compared to littermate matched wild-type, mutant AKT1, or mutant KRAS mice. Interestingly, mice with a combination of mutations that hyper-activated AKT1 and KRAS also showed faster development of pancreatic cancer compared to these other groups of littermate mice. Toward determining a molecular basis for the crosstalk between AKT1 and KRAS, pancreas and liver tissues were collected from all four groups of mice including wild-type, mutant AKT1, mutant KRAS, and mice with dual AKT1/KRAS hyper-activation. One strategy was to examine expression and/or phosphorylation of downstream protein signaling crosstalk by analysis of p70S6K using Western Blots. Erk 1/2 proteins were also tested as downstream proteins of KRAS to provide a molecular view of the individual and cooperative roles of AKT1 and KRAS in the mouse models. A potential feedback mechanism to affect insulin receptor signaling in the pancreas was examined using enzyme-linked immunosorbent assays (ELISA). A significant decrease in insulin receptor phosphorylation, possibly contributing to insulin resistance, was found when mice had mutant hyper-activated KRAS. Contrary to the original expectations, mice with combined mutations of AKT1 and KRAS may contribute to the accentuated diabetic phenotype by targeting two different points in the AKT and KRAS protein signaling pathways. The information can help understand the relationship between glucose metabolism, diabetes, and pancreatic cancer development. By thoroughly studying the interactions between targets in the AKT1/KRAS signaling pathways, key molecular events that induce metabolic changes and potentially early biomarkers may lead to an improved understanding of risk and/or detection of pancreatic cancer.
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Date Issued: 2017
Identifier: CFH2000273, ucf:45895
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH2000273

Title: EFFECTS OF DIETARY FACTORS ON THE INCIDENCE AND PROGRESSION OF NON-ALCOHOLIC FATTY LIVER DISEASE.
Creator: Lessans, Spencer L, Altomare, Deborah A., University of Central Florida
Abstract / Description: Non-alcoholic fatty liver disease (NAFLD) is a liver disorder linked to obesity that is rapidly increasing in incidence worldwide. It is a disorder that ranges in severity; from a benign condition of hepatic steatosis to a potentially deadly one resulting in cirrhosis and hepatocellular carcinoma. It is currently known that NAFLD is strongly associated with various aspects of metabolic syndrome: insulin resistance, elevated triglyceride levels, obesity, and type two diabetes mellitus. The...
Show moreNon-alcoholic fatty liver disease (NAFLD) is a liver disorder linked to obesity that is rapidly increasing in incidence worldwide. It is a disorder that ranges in severity; from a benign condition of hepatic steatosis to a potentially deadly one resulting in cirrhosis and hepatocellular carcinoma. It is currently known that NAFLD is strongly associated with various aspects of metabolic syndrome: insulin resistance, elevated triglyceride levels, obesity, and type two diabetes mellitus. The multifactorial pathogenesis of NAFLD is still uncertain and closer attention is needed on the effect of one's diet on NAFLD. In this study, we directly compare a westernized diet containing high levels of fat and fructose to a diet high in fat and containing cholate using mouse models in order to determine the role of each dietary factor in the incidence and severity of the different stages of NAFLD. We will evaluate the severity of hepatic steatosis and hepatocellular damage via hematoxylin and eosin (H&E) stained liver tissue and the severity of hepatic fibrosis via trichrome-stained liver tissue. Our hypothesis is that mice on the fructose-based diet are expected to have higher levels of hepatic steatosis and hepatocellular damage relative to mice on the cholate-based diet while mice on the cholate-based diet are expected to have higher levels of hepatic fibrosis relative to the fructose-based diet. The results of this study will aid in elucidating and strengthening the connection between one's diet and the prevalence and severity of NAFLD.
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Date Issued: 2018
Identifier: CFH2000340, ucf:45913
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH2000340

Title: POLYAMINE TRANSPORT INHIBITOR EFFECTS ON PANCREATIC CANCER PROLIFERATION CELLS IN VIVO.
Creator: Hogan, Frederick, Altomare, Deborah, University of Central Florida
Abstract / Description: Pancreatic cancer is a serious disease, one in which the survival rate over five years is less than 6%. (1) Often, malignant tumors will exhibit uncontrolled proliferation and it is postulated that they have high metabolic needs. One of the areas of interest in cancer metabolism is the unique need for large amounts of polyamines in order to sustain this uncontrolled proliferation. Polyamines are organic compounds that all cells need for proliferation and differentiation. (2) Cells obtain...
Show morePancreatic cancer is a serious disease, one in which the survival rate over five years is less than 6%. (1) Often, malignant tumors will exhibit uncontrolled proliferation and it is postulated that they have high metabolic needs. One of the areas of interest in cancer metabolism is the unique need for large amounts of polyamines in order to sustain this uncontrolled proliferation. Polyamines are organic compounds that all cells need for proliferation and differentiation. (2) Cells obtain polyamines by manufacture of them directly or obtain them from the environment through their transport across the cell membrane. When cancer cells have limited access to polyamines they enter apoptosis, or controlled cell death. In animal models of cancer, cellular apoptosis can be tracked by measuring tumor weights as well as histological methods. It is known that difluromethylornithine (DFMO), a polyamine synthesis inhibitor, has shown some success in reducing tumor weights. (3) Cells deprived of the ability to manufacture polyamines will resort to transporting existing polyamines from the environment for their use. (3) It is believed that a polyamine transport inhibitor (PTI) can be designed and used in conjunction with DFMO to completely deprive cancer cells of polyamines and increase rates of apoptosis in tumor cells. Through this study the interaction of DFMO with newly identified PTI will be analyzed. A mouse model with tumor cells in the pancreas will give a picture of how cancer cells react to DFMO / PTI in vivo. The findings allow us to postulate how targeted compounds interact with protein signaling pathways that may be important for regulating response to inhibitors of polyamine synthesis and/or transport.
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Date Issued: 2015
Identifier: CFH0004749, ucf:45395
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH0004749

Title: MICROENVIRONMENT CHANGES IN THE PANCREATIC STROMA INDUCED BY INFLAMMATION.
Creator: Cline, Kathryn, Altomare, Deborah A., University of Central Florida
Abstract / Description: Pancreatic cancer is the product of microenvironment alterations which emerge from inflammatory signaling and progress to more devastating cases such as Pancreatic Ductal Adenocarcinoma (PDAC). PDAC is extremely aggressive with a statistical five-year survival rate of merely 3%-5%, and is more than relevant to cancer research being that it is the fourth leading cause of cancer-related deaths in the US. Unfortunately pancreatic cancer is often unnoticed until reaching its hardly treatable end...
Show morePancreatic cancer is the product of microenvironment alterations which emerge from inflammatory signaling and progress to more devastating cases such as Pancreatic Ductal Adenocarcinoma (PDAC). PDAC is extremely aggressive with a statistical five-year survival rate of merely 3%-5%, and is more than relevant to cancer research being that it is the fourth leading cause of cancer-related deaths in the US. Unfortunately pancreatic cancer is often unnoticed until reaching its hardly treatable end stages, which perpetuates the low survival rate. The onset of PDAC may be facilitated by the activation of pancreatic stellate cells (PSCs), which secrete collagen and markedly contribute to tissue fibrosis. Inflammatory factors and activation of PSCs are hallmarks of pancreatitis and could increase occurrence rates of pancreatic cancer. The purpose of this thesis is to elucidate inflammatory signaling patterns starting with the onset of acute pancreatitis and through future studies of the more damaging states of chronic pancreatitis and cancer progression. Through the induction of acute pancreatitis in oncogenic and wild type mouse models and evaluating cytokine expression levels via RT-PCR a link between inflammatory signaling and disease state progression will be delineated. This model utilizes mice with mutant KRas, a gene activated in nearly all PDAC incidences, and constitutively active Akt, an oncogene activated in nearly all cancers. Preliminary results indicate that when experimentally inducing pancreatitis in mice predisposed to pancreatic cancer tissue remodeling and leukocyte infiltration is observed as a result of cytokine expression. Furthermore, macrophage and neutrophil stains are positive with one round of cerulein injections proving that acute inflammation is induced by these methods. Pancreatitis is a risk factor for pancreatic cancer which can be caused by environmental factors including smoking, alcohol consumption, and obesity. By understanding the mechanism by which inflammation occurs and the cytokine signaling involved we can attempt inhibit tumor-promoting signaling pathways in the pancreas stroma.
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Date Issued: 2016
Identifier: CFH2000104, ucf:45535
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH2000104

Title: MANIPULATING AKTIVATED METABOLISM VIA MTORC1.
Creator: von Hack-Prestinary, Ivan, Altomare, Deborah, University of Central Florida
Abstract / Description: Although poorly understood, normal cells and cancerous cells of the same type exhibit different patterns of nutrient consumption, processing and utility of metabolic substrates. Differences in substrate uptake, preference, and alternately emphasized metabolic pathways offer opportunities for selective targeting of cancer versus stroma. This may be accomplished by using a sequential approach of nutrient deprivation and pharmaceutical perturbation of metabolic pathways to inhibit cellular...
Show moreAlthough poorly understood, normal cells and cancerous cells of the same type exhibit different patterns of nutrient consumption, processing and utility of metabolic substrates. Differences in substrate uptake, preference, and alternately emphasized metabolic pathways offer opportunities for selective targeting of cancer versus stroma. This may be accomplished by using a sequential approach of nutrient deprivation and pharmaceutical perturbation of metabolic pathways to inhibit cellular proliferation. The purpose of this study was to investigate the effects of restricting glucose and glutamine concentrations, in vitro, to levels that resemble a potential human fasting state. The mammalian target of rapamycin (mTOR), a mediator of nutrient sensation, was then inhibited with rapamycin in the nutrient-restricted conditions. Because active Akt/mTOR is implicated in cancer cell pro-survival, the hypothesis is that pharmaceutical inhibition of active Akt/mTOR signaling in combination with the stress of restricted nutrient supply will be more effective than nutrient deprivation alone at disrupting metabolic processes to impair cancer cell proliferation and/or pro-survival mechanisms. Untreated and treated conditions were tested to determine if an additive or synergistic effect would result from a sequential insult of nutrient deprivation followed by inhibited mTORC1 signaling. The cell line used for this study was cultivated from a murine pancreatic intraepithelial neoplasia (PANIN) derived from a transgenic mouse with pancreatic tissue-specific expression of constitutively active Akt. The transgene of Akt, isoform 1, contains a myristoyl tag that facilitates co-localization of Akt to the plasma membrane, thereby promoting the activation of this signaling protein. This aberrantly activated Akt represents a prosurvival condition observed in most cancers, and impacts metabolic balance with increased downstream signaling to metabolic sensors and regulators, including mTORC1. Several methods were used to evaluate changes in metabolic and physiological response to nutrient deprivation and mTORC1 inhibition. These included tetrazolium reduction/absorbance readings to qualitatively evaluate differences in cell proliferation, and Western immunoblots for observing changes in protein expression and phosphorylation. ATP luminescence assays were applied to quantify intracellular ATP content, and citrate synthase spectrophotometry used to quantify specific activity/indicate changes in the TCA/OXPHOS production of ATP. Results from the above methods suggest that, individually, nutrient deprivation and rapamycin treatment share some similar effects on metabolically-related protein phosphorylation and in reducing cellular proliferation. Collectively, nutrient deprivation plus rapamycin treatment, however, resulted in unanticipated metabolic alterations under conditions used for this study, the complexities of which would need to be delineated in future studies.
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Date Issued: 2013
Identifier: CFH0004373, ucf:45006
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH0004373

Title: Role of Lipid Peroxide Derived Dicarboxylic Acids in Atherosclerotic Calcification.
Creator: Riad, Aladdin, Parthasarathy, Sampath, Altomare, Deborah, Masternak, Michal, Naser, Saleh, University of Central Florida
Abstract / Description: Cardiovascular diseases, including atherosclerosis, are the leading cause of death in the United States. Atherosclerotic lesions are formed by deposition of lipids in the intima of arteries. Upon exposure to oxidative stresses, low-density lipoprotein (LDL) is converted to highly atherogenic oxidized LDL (ox-LDL) particles, contributing to disease development and progression. Advanced disease stages may result in calcification of lesions. This calcification process is important, as it has...
Show moreCardiovascular diseases, including atherosclerosis, are the leading cause of death in the United States. Atherosclerotic lesions are formed by deposition of lipids in the intima of arteries. Upon exposure to oxidative stresses, low-density lipoprotein (LDL) is converted to highly atherogenic oxidized LDL (ox-LDL) particles, contributing to disease development and progression. Advanced disease stages may result in calcification of lesions. This calcification process is important, as it has been shown to be associated with stable plaques that are less prone to rupture. Calcification is present in lipid rich domains of lesions, however neither the composition of the mineralized calcium deposits nor its relationship to lipid peroxidation or the lipid rich atherosclerotic core has previously been identified. This study provides evidence that the lipid peroxide derived dicarboxylic acid (DCA), azelaic acid (AzA) induces calcification in smooth muscle cells, thereby providing the link between calcification and overall plaque burden, and association of calcification with the lipophilic region of the lesion. The potential of lipid peroxide-derived lipophilic DCAs to promote calcification upon exposure to vascular smooth muscle cells was tested. 13-hydroperoxylinoleic acid (HPODE) treatment resulted in the cellular conversion to 9-oxononanoic acid (ONA) and AzA as determined by mass spectrometry analysis. Delivery of AzA via lysophosphatidylcholine (Lyso-PtdCho) micelles induced calcification of human aortic smooth muscle cells (HASMC). AzA was identified in calcified human and mouse atherosclerotic plaques. Calcification of HASMC due to AzA treatment resulted in a less inflammatory and oxidative environment as indicated by genetic expression. These results demonstrate that DCAs may contribute to atherosclerotic calcification thus accounting for the latter's relationship to plaque burden and association with lipids. This study also challenges the dogma that arterial calcification represents the deposition of calcium phosphate and has implications with the development of new therapeutic strategies in treating late stage atherosclerosis.
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Date Issued: 2018
Identifier: CFE0007413, ucf:52730
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007413

Title: Metabolic Effects of 17a-Estradiol are Growth Hormone Independent and Sex Specific.
Creator: Sidhom, Silvana, Masternak, Michal, Altomare, Deborah, Siddiqi, Shadab, University of Central Florida
Abstract / Description: Aging is a major risk factor for metabolic syndromes and type two diabetes. With growing elderly populations worldwide and increasing incidence of age-related diseases there is a great need to develop pharmacological interventions that would delay aging and protect from age-related diseases. 17-alpha estradiol (17?-E2) is an epimer of the primary female sex hormone estradiol and has been shown to extend lifespan and downregulate markers of age-related metabolic dysfunction in male mice....
Show moreAging is a major risk factor for metabolic syndromes and type two diabetes. With growing elderly populations worldwide and increasing incidence of age-related diseases there is a great need to develop pharmacological interventions that would delay aging and protect from age-related diseases. 17-alpha estradiol (17?-E2) is an epimer of the primary female sex hormone estradiol and has been shown to extend lifespan and downregulate markers of age-related metabolic dysfunction in male mice. Because 17?-E2 does not induce feminization in males it holds potential as a novel therapeutic in humans for age-related metabolic dysfunction. Importantly, we have previously shown that 17?-E2 causes an increase of circulating and hepatic IGF-1 in aged mice, without any changes in GH release in treated animals. Based on this we propose a new hypothesis that 17?-E2 acts through a novel, GH-independent pathway stimulating production of IGF-1 and positively modulating metabolic function in a sex-specific manner. Here we studied 17?-E2 treated long-lived growth hormone receptor knockout (GHRKO) mice, characterized by severely reduced circulating and hepatic IGF-1 due to GH-resistance. We found increases in circulating IGF-1 after treatment in normal and GHRKO male mice, with no effect in female mice, which supports our hypothesis that 17?-E2 induces GH independent IGF-1 production. To determine novel genetic pathways activated by 17?-E2 we performed sequencing of hepatic RNA. Our analysis indicated differential regulation of steroid biosynthesis and insulin signaling pathways. The validation of our sequencing data using qPCR showed significant upregulation of genes involved in insulin action. Importantly, differential regulation of these pathways was present in normal male mice, with no changes in normal females or either male or female GHRKO animals. In summary, this new data supports our hypothesis of a sex-specific effect of 17?-E2 treatment and differing mechanisms of action by which 17?-E2 upregulates IGF-1 independently of GH action.
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Date Issued: 2019
Identifier: CFE0007726, ucf:52424
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007726

Title: Alpha-Tocopherol Reduces VLDL Secretion Through Modulation of the VLDL Transport Vesicle.
Creator: Clay, Ryan, Siddiqi, Shadab, Altomare, Deborah, Masternak, Michal, University of Central Florida
Abstract / Description: The liver distributes serum triacylglycerol (TAG) via the very low-density lipoprotein (VLDL), and an increase in VLDL production may result in hyperlipidemia. VLDL synthesis consists of lipidation of Apolipoprotein B100 (ApoB) as it is co- translationally translocated across the endoplasmic reticulum (ER) membrane, and this nascent VLDL particle must undergo subsequent maturation and post-translational modification in the Golgi. The ER-to-Golgi trafficking of VLDL represents the rate...
Show moreThe liver distributes serum triacylglycerol (TAG) via the very low-density lipoprotein (VLDL), and an increase in VLDL production may result in hyperlipidemia. VLDL synthesis consists of lipidation of Apolipoprotein B100 (ApoB) as it is co- translationally translocated across the endoplasmic reticulum (ER) membrane, and this nascent VLDL particle must undergo subsequent maturation and post-translational modification in the Golgi. The ER-to-Golgi trafficking of VLDL represents the rate-limiting step in VLDL secretion and is mediated by the VLDL Transport Vesicle (VTV). Many in vivo studies have indicated that vitamin E (alpha-tocopherol) supplementation protects against atherosclerosis and can reduce hepatic steatosis in nonalcoholic fatty liver disease (NAFLD), but its effects at the molecular level on hepatic lipid metabolism are poorly understood. To investigate the effects of alpha-tocopherol on hepatic VLDL secretion and cellular lipid retention, we performed several experiments in HepG2 (human) and McARH- 7777 (rat) hepatoma cell lines including pulse-chase experiments using 3H-oleic acid (3H- OA), confocal microscopy with BODIPY lipid droplet staining, and an in vitro VTV budding assay. Our results demonstrate a significant reduction of 3H-TAG secretion and ApoB media expression in response to 100 uM alpha-tocopherol, with a corresponding decrease in markers of VTV biogenesis in western blots of whole cell lysates (WCL) and retention of ApoB within the cell, indicating disruption of an early step in VLDL biogenesis. Further evidence indicates an increase in size and lipidation of the VTV and VLDL particle. BODIPY staining as well as 3H-TAG retention in WCLs was also sharply reduced. Overall, these results indicate that alpha-tocopherol reduces VLDL secretion, partially disrupts hepatic VLDL synthesis and VTV biogenesis, increases the lipidation of remaining VLDL particles, and diminishes overall cellular lipid droplet retention.
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Date Issued: 2019
Identifier: CFE0007617, ucf:52538
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007617

Title: Diabetes Phenotypes in Transgenic Pancreatic Cancer Mouse Models.
Creator: Albury, Toya, Altomare, Deborah, Zhao, Jihe, Masternak, Michal, Khaled, Annette, University of Central Florida
Abstract / Description: Protein Kinase B/AKT, a serine/threonine kinase with three isoforms (AKT1-3), is downstream of phosphatidylinositol 3-kinase (PI3K), and signals through the phosphorylation and subsequent activation or inhibition of downstream substrates, such as mammalian target of rapamycin complex 1 (mTORC1) or glycogen synthase kinase 3 beta (GSK-3?), respectively. The AKT1 isoform is predominantly recognized for regulation of cell survival, growth, and proliferation, due to its constitutive activation in...
Show moreProtein Kinase B/AKT, a serine/threonine kinase with three isoforms (AKT1-3), is downstream of phosphatidylinositol 3-kinase (PI3K), and signals through the phosphorylation and subsequent activation or inhibition of downstream substrates, such as mammalian target of rapamycin complex 1 (mTORC1) or glycogen synthase kinase 3 beta (GSK-3?), respectively. The AKT1 isoform is predominantly recognized for regulation of cell survival, growth, and proliferation, due to its constitutive activation in pancreatic cancers (e.g., islet cell carcinoma and pancreatic adenocarcinoma). The progression of pancreatic ductal adenocarcinoma (PDAC), the most lethal common cancer, is initiated by activation mutations of the KRas oncogene. This leads to additional molecular changes, such as activation of the AKT1 oncogene, which drives PDAC progression and tumor formation. By mating transgenic mice with activation of KRas (Pdx- Cre;LSL-KRasG12D) and mice with activation of AKT1 (Pdx- Tta;TetO-MyrAKT1) we were able to produce mice with two activated oncogenes (AKT1Myr/KRasG12D) for comparative studies. Kaplan-Meier survival curves, histology, and genomic/proteomic analysis were used to characterize the incidence and frequency of histological (e.g. presence of mucin-4 in pancreatic intraepithelial neoplasms) and genetic (e.g. loss of tumor suppressors p16Ink4a and p19Arf) alterations known to commonly occur in human pancreatic cancer, as well as delineate the role of AKT1 in accelerating pancreatic tumor progression and metastasis. We determined that AKT1Myr/KRasG12D mice, unlike other PDAC mouse models, accurately mimic the human PDAC progression molecularly, structurally, and temporally. Interestingly, the AKT1Myr and AKT1Myr/KRasG12D models both exhibit a pre-tumor, diabetic phenotype. While, AKT1 hyperactivation in various cancers has been thoroughly studied, its role in glucose metabolism has been noted, but comparatively overlooked. As early as the 1900s a relationship between diabetes and pancreatic cancer has been proposed. With 80% of PDAC patients suffering from hyperglycemia or diabetes prior to diagnosis, one prevailing theory is that new onset diabetes is an early marker for pancreatic cancer. This is also supported by experimental and clinical studies, such as the resolution of diabetes with tumor removal and the induction of hyperglycemia with the implantation of cancer cell lines. To better understand the role of AKT1 and its hyperactivation in glucose metabolism, AKT1Myr mice were characterized via metabolic (e.g. glucose/insulin tolerance test) and histological (e.g. immunohistochemistry) studies. Beginning at weaning, 3 weeks of age, the glucose intolerant AKT1Myr mice exhibited non-fasted hyperglycemia, which progressed to fasted hyperglycemia by 5 months of age. The glucose intolerance was attributed to a fasted hyperglucagonemia, and hepatic insulin resistance detectable by reduced phosphorylation of the insulin receptor following insulin injection into the inferior vena cava. Additionally, AKT1Myr/KRasG12D mice currently being studied, appear to display a more severe diabetic phenotype, with fasted hyperglycemia noticeable at an earlier age, fasted hyperglucagonemia, polyuria, muscle wasting, and bloating. Treatment of both models with doxycycline diet, to turn-off the transgene, caused attenuation of the non-fasted and fasted hyperglycemia, thus affirming AKT1 hyperactivation as the trigger. These newly revealed roles of AKT1, along with future studies of these mouse models, will better delineate the molecular mechanisms responsible for the individual and joint roles of AKT1 and KRas in pancreatic cancer oncogenesis, the initiation of cancer associated diabetes, and the association of these two diseases.
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Date Issued: 2015
Identifier: CFE0006245, ucf:51081
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006245

Title: Cerium Oxide Nanoparticles Sensitize Pancreatic Cancer Cells to Radiation by Promoting Acidic pH, ROS, and JNK Dependent Apoptosis.
Creator: Wason, Melissa, Zhao, Jihe, Self, William, Altomare, Deborah, Baker, Cheryl, University of Central Florida
Abstract / Description: Side effects of radiation therapy (RT) remain the most challenging issue for pancreatic cancer treatment. In this report we determined whether and how cerium oxide nanoparticles (CONPs) sensitize pancreatic cancer cells to RT. CONP pretreatment enhanced radiation-induced reactive oxygen species (ROS) production preferentially in acidic cell-free solutions as well as acidic human pancreatic cancer cells. In acidic environments, CONPs favor the scavenging of superoxide radical over the hydroxyl...
Show moreSide effects of radiation therapy (RT) remain the most challenging issue for pancreatic cancer treatment. In this report we determined whether and how cerium oxide nanoparticles (CONPs) sensitize pancreatic cancer cells to RT. CONP pretreatment enhanced radiation-induced reactive oxygen species (ROS) production preferentially in acidic cell-free solutions as well as acidic human pancreatic cancer cells. In acidic environments, CONPs favor the scavenging of superoxide radical over the hydroxyl peroxide resulting in accumulation of the latter whereas in neutral pH CONPs scavenge both. CONP treatment prior to RT markedly potentiated the cancer cell apoptosis both in culture and in tumors and the inhibition of the pancreatic tumor growth without harming the normal tissues or host mice. Mechanistically, CONPs were not able to significantly impact RT-induced DNA damage in cancer cells, thereby ruling out sensitization through increased mitotic catastrophe. However, JNK activation, which is known to be a key driver of RT-induced apoptosis, was significantly upregulated by co-treatment with CONPs and RT in pancreatic cancer cells in vitro and human pancreatic tumors in nude mice in vivo compared to CONPs or RT treatment alone. Further, CONP-driven increase in RT-induced JNK activation was associated with marked increases in Caspase 3/7 activation, indicative of apoptosis. We have shown CONPs increase ROS production in cancer cells; ROS has been shown to drive the oxidation of thioredoxin (TRX) 1 which results in the activation of Apoptosis Signaling Kinase (ASK) 1. The dramatic increase in ASK1 activation following the co-treatment of pancreatic cancer cells with CONPs followed by RT in vitro suggests that increased the c-Jun terminal kinase (JNK) activation is the result of increased TRX1 oxidation. The ability of CONPs to sensitize pancreatic cancer cells to RT was mitigated when the TRX1 oxidation was prevented by mutagenesis of a cysteine residue, or the JNK activation was blocked by an inhibitor,. Additionally, angiogenesis in pancreatic tumors treated with CONPs and RT was significantly reduced compared to other treatment options. Taken together, these data demonstrate an important role and mechanisms for CONPs in specifically killing cancer cells and provide novel insight into the utilization of CONPs as a radiosensitizer and therapeutic agent for pancreatic cancer.
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Date Issued: 2013
Identifier: CFE0005116, ucf:50725
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005116

Title: Development of Cytotoxic Natural Killer Cells for Ovarian Cancer Treatment.
Creator: Pandey, Veethika, Altomare, Deborah, Zhao, Jihe, Khaled, Annette, Estevez, Alvaro, University of Central Florida
Abstract / Description: Ovarian cancer is a leading cause of gynecological malignancy. Cytoreductive surgery and frontline platinum/taxane-based chemotherapy provides good initial efficacy in the treatment, but poor long-term patient survival. This is mainly caused by tumor relapse due to intraperitoneal spreading and ineffective alternate therapies to treat these resistant tumors. The challenge in the field is to develop strategies that would prove effective in these patients and extend overall survival.Over the...
Show moreOvarian cancer is a leading cause of gynecological malignancy. Cytoreductive surgery and frontline platinum/taxane-based chemotherapy provides good initial efficacy in the treatment, but poor long-term patient survival. This is mainly caused by tumor relapse due to intraperitoneal spreading and ineffective alternate therapies to treat these resistant tumors. The challenge in the field is to develop strategies that would prove effective in these patients and extend overall survival.Over the years, various treatments have been developed for the treatment of cancer amongst which, adoptive cell immunotherapy has shown promising results. But despite the efficacy seen in the clinic, there are concerns with the complexity of treatment and associated side effects. Therefore, there is still a need for better understanding of how different components of the immune system react to the presence of tumor. In this study, healthy human peripheral blood mononuclear cells (PBMCs) were used to examine the immune response in a mouse model with residual human ovarian tumor, where natural killer (NK) cells were found to be the effector cells that elicited an anti-tumor response. Presence of tumor was found to stimulate NK cell expansion and cytotoxicity in mice treated intraperitoneally (IP) with PBMCs+Interleukin-2 (IL- 2). Intravenous (IV) adoptive transfer of isolated NK cells has been attempted in ovarian cancer patients before, but showed lack of persistence in patients resulting in lack of anti-tumor efficacy. Experiments in this study highlight the significance of NK cell-cytotoxic response to tumor, which may be attributed to interacting immune cell types in the PBMC population (when treated IP), as opposed to clinically used isolated NK cells showing lack of anti-tumor efficacy in ovarian cancer patients (when treated IV).iiiNK cell immunotherapy is mainly limited by insufficient numbers generated for adoptive transfer, limited in vivo life span after adoptive transfer, lack of cytotoxicity and some logistical concerns that impede its widespread implementation. Therefore there is a need to develop methods of NK cell expansion that provide stimulation similar to other immune cell types in the PBMC population. The second part of this study utilizes a method of in vivo NK cell expansion using a particle-based approach in which plasma membranes of K562-MB21-41BBL cells (K562 cells expressing membrane-bound IL-21 and 41BB ligand) are used for specific NK cell expansion from PBMCs. NK cells expanded with this method were cytotoxic, showed in vivo persistence and biodistribution in different organs.Collectively, these studies show that NK cells are a major innate immune component that can recognize and kill the tumor. Their cytotoxic ability, using particle-based stimulation, can be enhanced for a second-line treatment of relapsed tumors such as in ovarian cancer as well as other cancer types.
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Date Issued: 2015
Identifier: CFE0006369, ucf:51531
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006369

Title: The Role of Type-I Interferon in Limiting Spread and Killing of an Oncolytic RNA Virus in Prostate Cells.
Creator: Kedarinath, Kritika, Parks, Griffith, Chakrabarti, Ratna, Altomare, Deborah, University of Central Florida
Abstract / Description: Prostate cancer is the second most prevalent cancer amongst men and there is an urgent need to address viable therapeutic options for its treatment. Development of viruses which target and kill cancer cells has gained momentum due to the first FDA approved oncolytic virus for treating human cancer patients. Our previous work with the RNA virus, Parainfluenza Virus 5 (PIV5), has led to the generation of mutants that are potential candidates for oncolytic viruses: 1) the hyperfusogenic (P/V/F)...
Show moreProstate cancer is the second most prevalent cancer amongst men and there is an urgent need to address viable therapeutic options for its treatment. Development of viruses which target and kill cancer cells has gained momentum due to the first FDA approved oncolytic virus for treating human cancer patients. Our previous work with the RNA virus, Parainfluenza Virus 5 (PIV5), has led to the generation of mutants that are potential candidates for oncolytic viruses: 1) the hyperfusogenic (P/V/F) mutant has a mutated P/V and fusion gene which activates anti-viral responses and causes massive cell-cell fusion respectively, and 2) the Leader mutant has a mutated viral genomic promoter which kills cells due to overactive viral gene expression. The P/V/F mutant has shown effectiveness in reducing prostate tumor burden in a mouse model system, however, the specificity of these viruses is unclear, i.e. targeting cancerous prostate cells while leaving uninvolved cells unaffected. In this study, we addressed how these PIV5 mutants replicate in and killed tumor versus benign human prostate cells. Flow cytometry demonstrated that the mutants are able to infect and replicate in prostate tumor cells (22Rv1), resulting in effective cell killing. However, these mutants showed highly restricted spread in benign prostatic hyperplasia cells (BPH-1). Upon further exploration, it was determined that the restriction observed in the BPH-1 cells is due to the induction and signaling of type-I Interferon (IFN). This was confirmed upon treatment with an IFN-? neutralizing antibody, which relieved restricted spread of mutants in benign cells. BPH-1 cells infected with the mutants also showed upregulation of key anti-viral, IFN-induced genes such as TLR3, IFIT1, and OAS2. Upon characterization of the mutant viruses in an additional metastatic prostate cancer cell line (C4-2B), a restriction in viral spread was observed. The restricted spread did not correlate with production of high levels of type-I IFN, suggesting that other cytokines or intracellular factors can limit replication in tumor cells. Therefore, these studies lay the groundwork for further improving the specificity of oncolytic PIV5 mutants by exploiting type-I IFN pathways as well as other anti-viral factors.
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Date Issued: 2016
Identifier: CFE0006468, ucf:51445
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006468

Title: Role of KLF8-CXCR4 signaling in Breast Cancer Metastasis.
Creator: Mukherjee, Debarati, Zhao, Jihe, Khaled, Annette, Altomare, Deborah, Siddiqi, Shadab, University of Central Florida
Abstract / Description: Kr(&)#252;ppel-like factor 8 (KLF8) has been strongly implicated in breast cancer metastasis. However, the underlying mechanisms remain largely unknown. In this study we report a novel signaling from KLF8 to C-X-C cytokine receptor type 4 (CXCR4) in breast cancer. Overexpression of KLF8 in MCF-10A cells induced CXCR4 expression at both mRNA and protein levels. This induction was well correlated with increased Boyden chamber migration, matrigel invasion and transendothelial migration (TEM) of...
Show moreKr(&)#252;ppel-like factor 8 (KLF8) has been strongly implicated in breast cancer metastasis. However, the underlying mechanisms remain largely unknown. In this study we report a novel signaling from KLF8 to C-X-C cytokine receptor type 4 (CXCR4) in breast cancer. Overexpression of KLF8 in MCF-10A cells induced CXCR4 expression at both mRNA and protein levels. This induction was well correlated with increased Boyden chamber migration, matrigel invasion and transendothelial migration (TEM) of the cells towards the ligand CXCL12. On the other hand, knockdown of KLF8 in MDA-MB-231 cells reduced CXCR4 expression associated with decreased cell migration, invasion and TEM towards CXCL12. Histological and database mining analyses of independent cohorts of patient tissue microarrays revealed a correlation of aberrant co-elevation of KLF8 and CXCR4 with metastatic potential. Promoter analysis indicated that KLF8 directly binds and activates the human CXCR4 gene promoter. Furthermore, CXCR4-CXCL12 engagement downstream of KLF8 leads to the feed-forward activation of FAK. Interestingly, KLF8 expression, through CXCR4 engagement, triggered the formation of filopodium-like protrusions (FLP) and thereby enhanced the proliferation rate of breast cancer cells in 3D Matrigel-on-Top culture, under prolonged treatment with CXCL12. This indicates that KLF8 plays a major role in promoting aggressive colonization of tumor cells in a CXCL12-enriched foreign tissue microenvironment, thereby aiding in secondary macrometastasis formation. Xenograft studies showed that overexpression of CXCR4, but not a dominant-negative mutant of it, in the MDA-MB-231 cells prevented the invasive growth of primary tumor and lung metastasis from inhibition by knockdown of KLF8. Apart from lung, KLF8 overexpression also induced spontaneous secondary metastasis to other CXCL12-rich organs through CXCR4 signaling. These results collectively suggest a critical role for KLF8 and the CXCR4-CXCL12 pathway in promoting breast cancer metastasis and shed new light on potentially more effective anti-cancer strategies.
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Date Issued: 2016
Identifier: CFE0006149, ucf:51127
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006149

Title: The CT20 peptide as an agent for cancer treatment.
Creator: Bassiouni, Rania, Khaled, Annette, Altomare, Deborah, Zhao, Jihe, Estevez, Alvaro, University of Central Florida
Abstract / Description: Due to cancer recurrence and the development of drug resistance, metastatic breast cancer is a leading cause of death in women. In the search for a new therapeutic to treat metastatic disease, we discovered CT20p, an amphipathic peptide based on the C-terminus of Bax. Due to inherent properties of its sequence and similarity to antimicrobial peptides, CT20p is a promising cytotoxic agent whose activity is distinct from the parent protein (e.g. does not cause apoptosis). CT20p is not membrane...
Show moreDue to cancer recurrence and the development of drug resistance, metastatic breast cancer is a leading cause of death in women. In the search for a new therapeutic to treat metastatic disease, we discovered CT20p, an amphipathic peptide based on the C-terminus of Bax. Due to inherent properties of its sequence and similarity to antimicrobial peptides, CT20p is a promising cytotoxic agent whose activity is distinct from the parent protein (e.g. does not cause apoptosis). CT20p is not membrane permeable but can be introduced to cells using polymeric nanoparticles, a method that promotes efficient delivery of the peptide into the intracellular environment.We demonstrated that CT20p was cytotoxic using triple negative breast cancer (TNBC) cell lines, primary breast tumor tissue, and breast tumor murine xenografts. Importantly, normal breast epithelial cells and normal primary breast cells were resistant to the lethal effects of the peptide. Examination of multiple cellular processes showed that CT20p causes cell death by promoting cytoskeletal disruption, cell detachment, and loss of substrate-mediated survival signals.In order to identify the intracellular target of CT20p, we performed pull-down experiments using a biotinylated peptide and found that CT20p binds directly to a type II chaperonin called chaperonin containing T-complex (CCT), which is essential for the folding of actin and tubulin into their native forms. The resulting effect of CT20p upon the cytoskeleton of cancer cells is disruption of vital cellular processes such as migration and adhesion. CCT gene expression and protein levels were examined across several breast cancer cell lines, and we found that susceptibility to CT20p correlated with higher CCT levels. Using human cancer tissue microarrays, we determined that CCT was present in significantly higher amounts in tumor tissues compared to normal tissues and that expression often increased with advanced cancer stage. These results indicate that CCT is a promising therapeutic target for the treatment of metastatic breast cancer and suggest that the use of cancer-targeted nanoparticles loaded with CT20p is a novel and effective therapeutic strategy for cancers, such as TNBC, that recur and are refractory to current treatments.
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Date Issued: 2015
Identifier: CFE0006207, ucf:51095
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006207

Title: The contribution of visceral fat to positive insulin signaling in Ames dwarf mice.
Creator: Menon, Vinal, Masternak, Michal, Khaled, Annette, Altomare, Deborah, Estevez, Alvaro, University of Central Florida
Abstract / Description: Ames dwarf (df/df) mice are homozygous for a spontaneous mutation in the prop1 gene due to which there is no development of anterior pituitary cells (-) somatotrophs, lactotrophs and thyrotrophs, leading to a deficiency of growth hormone (GH), prolactin (PRL) and thyrotropin (TSH). They tend to become obese as they age, but still live longer and healthier lives compared to their wild-type littermates, being very insulin sensitive, showing no signs of diabetes and cancer. These mutant mice...
Show moreAmes dwarf (df/df) mice are homozygous for a spontaneous mutation in the prop1 gene due to which there is no development of anterior pituitary cells (-) somatotrophs, lactotrophs and thyrotrophs, leading to a deficiency of growth hormone (GH), prolactin (PRL) and thyrotropin (TSH). They tend to become obese as they age, but still live longer and healthier lives compared to their wild-type littermates, being very insulin sensitive, showing no signs of diabetes and cancer. These mutant mice also have high circulating levels of anti-inflammatory and anti-diabetic adiponectin. Plasma levels of this adipokine usually decrease with an increase in accumulation of visceral fat (VF). We thus believe that VF in df/df mice, developed in the absence of GH signaling, may be functionally different from the same fat depots in normal (N) mice and may be beneficial, rather than detrimental, to the overall health of the animal. We performed surgeries involving removal of VF depots (epididymal and perirenal fat) in both groups of mice and hypothesize that the beneficial effects of visceral fat removal (VFR) will be present exclusively in N mice as VF in df/df mice contributes to enhanced insulin sensitivity by producing decreased levels of pro-inflammatory adipokines like TNF? and IL-6. We found that VFR improved insulin sensitivity only in N mice but not in the df/df mice. This intervention led to an upregulation of certain players of the insulin signaling pathway in the skeletal muscle of N mice only, with no alteration in df/df mice. The subcutaneous fat of df/df mice showed a downregulation of these insulin signaling genes upon VFR. Compared to N mice, epididymal fat of df/df mice (sham-operated) had increased gene expression of some of the players involved in insulin signaling and a decrease in transcript levels of TNFa. Ames dwarf mice had decreased levels of IL-6 protein in EF and in circulation. High circulating levels of adiponectin and decreased levels of IL-6 in circulation could contribute to the high insulin sensitivity observed in the Ames dwarf mice. Understanding the mechanisms responsible for VF having positive effects on insulin signaling in df/df mice would be important for future treatment of obese diabetic patients.
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Date Issued: 2013
Identifier: CFE0004890, ucf:49654
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004890

Title: IDENTIFICATION OF EPITHELIAL STROMAL INTERACTION 1 AND EPIDERMAL GROWTH FACTOR RECEPTOR AS NOVEL KR(&)#220;PPEL-LIKE FACTOR 8 TARGETS IN PROMOTING BREAST CANCER PROGRESSION.
Creator: Li, Tianshu, Zhao, Jihe, Khaled, Annette, Altomare, Deborah, Lambert, Stephen, University of Central Florida
Abstract / Description: Breast cancer is the major cause of cancer death among women worldwide. Understanding the mechanisms underlying breast cancer progression remains urgent for developing effective treatment strategies to eliminate breast cancer mortality. Our recent studies have demonstrated that Kr(&)#252;ppel-like transcriptional factor 8 (KLF8) plays a critical role for breast cancer progression. Other studies have shown that Epithelial stromal interaction 1 (EPSTI1), a recently identified stromal fibroblast...
Show moreBreast cancer is the major cause of cancer death among women worldwide. Understanding the mechanisms underlying breast cancer progression remains urgent for developing effective treatment strategies to eliminate breast cancer mortality. Our recent studies have demonstrated that Kr(&)#252;ppel-like transcriptional factor 8 (KLF8) plays a critical role for breast cancer progression. Other studies have shown that Epithelial stromal interaction 1 (EPSTI1), a recently identified stromal fibroblast-induced gene in non-invasive breast cancer cells and epidermal growth factor receptor (EGFR) are highly overexpressed in aggressively invasive breast carcinomas including triple negative breast cancers. In this thesis project, we demonstrate high co-overexpression of KLF8 with EPSTI1 as well as EGFR in invasive breast cancer cells and patient tumors. We also show that KLF8 upregulates the expression of EPSTI1 by directly binding and activating the EPSTI1 gene promoter, and KLF8 upregulates the expression of EGFR not only by directly activating the EGFR gene promoter but also by preventing EGFR translation from microRNA141-dependent inhibition. Genetic, signaling and animal cancer model analyses indicate that downstream of KLF8, EPSTI1 promotes the tumor invasion and metastasis by activating NF-?B through binding valosin containing protein (VCP) and subsequent degradation of I?B?, whereas EGFR promotes tumor growth and metastasis via activation of ERK. Taken together, these data identify EPSTI1 and EGFR as novel KLF8 targets in breast cancer and suggest that KLF8 may be targeted for new effective treatment of breast cancer.
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Date Issued: 2013
Identifier: CFE0005366, ucf:50474
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005366

Title: A novel link between Akt1 and Twist1 in ovarian tumor cell motility and invasiveness.
Creator: Shah, Nirav, Altomare, Deborah, Zhao, Jihe, Khaled, Annette, University of Central Florida
Abstract / Description: Ovarian cancer results in more deaths per year than any other cancer of the female reproductive system. The low survival rate is partly due to the lack of early detection and the susceptibility to relapse. The AKT serine threonine kinase plays a pivotal role in hallmark cellular processes for the progression of ovarian cancer, including tumor cell growth and migration. Therapeutic targeting of pan-AKT has been problematic, in part due to feedback mechanisms and crosstalk with other pathways....
Show moreOvarian cancer results in more deaths per year than any other cancer of the female reproductive system. The low survival rate is partly due to the lack of early detection and the susceptibility to relapse. The AKT serine threonine kinase plays a pivotal role in hallmark cellular processes for the progression of ovarian cancer, including tumor cell growth and migration. Therapeutic targeting of pan-AKT has been problematic, in part due to feedback mechanisms and crosstalk with other pathways. The hypothesis for this study is that AKT 1, -2 and -3 isoforms may have different roles and regulate cell processes in uniquely varied ways. A transgenic mouse model that expresses the SV40 T-antigen viral oncogene and is known to have dramatically increased susceptibility to ovarian cancer was utilized, and it had genetic inactivation of either AKT1 or AKT2 through targeted deletion of the individual genes because these isoforms have been implicated in this cancer. Primary ovarian tumor cell cultures were established and found to exhibit different morphology, proliferation and migration that may indicate a different role for the AKT1 and AKT2 isoforms in these contexts. Ovarian tumor cells with absence of AKT1 predominantly exhibited reduced cell migration when compared to cells with retention of AKT1 and absence of AKT2. Since AKT is known to be important for epithelial-mesenchymal transition (EMT), a process potentially associated with tumor cell metastasis, the expression of transcription factors implicated in EMT was assessed by real-time array analysis in ovarian tumor cells knocked-out for either AKT1 or AKT2. Twist1, one of the major players in EMT, was not detectable in the cells missing the AKT1 isoform. Results indicate an association of Twist1 with AKT1 in EMT and migration of ovarian tumors cells. This finding is significant because AKT2 has been implicated as the major player of cell migration in human breast cancer cells. Collectively, these findings support a tissue specific role of the AKT isoforms, and may provide insights regarding the most useful cell context in order to target components of the AKT signaling pathway indirectly affecting EMT in order to prevent tumor progression in patients with ovarian and perhaps other types of cancers.
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Date Issued: 2012
Identifier: CFE0004630, ucf:49916
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004630

Title: Neuromuscular junction defects in a mouse model of Charcot-Marie-Tooth disease type 2O.
Creator: Sabblah, Thywill, Kim, Yoon-Seong, King, Stephen, Bossy-Wetzel, Ella, Altomare, Deborah, University of Central Florida
Abstract / Description: Charcot Marie Tooth disease (CMT) represents the most common inheritable peripheral group of motor and sensory disorders; affecting 1 in 2500 people worldwide. Individuals with CMT experience slow progressing weakness of the muscle, atrophy, mild loss of motor coordination and in some cases loss of sensory function in the hands and feet which could ultimately affect mobility. Dynein is an essential molecular motor that functions to transport cargos in all cells. A point mutation in the dynein...
Show moreCharcot Marie Tooth disease (CMT) represents the most common inheritable peripheral group of motor and sensory disorders; affecting 1 in 2500 people worldwide. Individuals with CMT experience slow progressing weakness of the muscle, atrophy, mild loss of motor coordination and in some cases loss of sensory function in the hands and feet which could ultimately affect mobility. Dynein is an essential molecular motor that functions to transport cargos in all cells. A point mutation in the dynein heavy chain was discovered to cause CMT disease in humans, specifically CMT type 2O. We generated a knock-in mouse model bearing the same mutation(H304R) in the dynein heavy chain to study the disease. We utilized behavioral assays to determine whether our mutant mice had a phenotype linked to CMT disease. The mutant mice had motor coordination defects and reduced muscle strength compared to normal mice. To better understand the disease pathway, we obtained homozygous mutants from a heterozygous cross, and the homozygotes show even more severe deficits compared to heterozygotes. They also developed an abnormal gait which separates them from heterozygous mice. In view of the locomotor deficits observed in mutants, we examined the neuromuscular junction (NMJ) for possible impairments. We identified defects in innervation at the later stages of the study and abnormal NMJ architecture in the muscle as well. The dysmorphology of the NMJ was again worse in the homozygous mutants with reduced complexity and denervation at all the timepoints assessed. Our homozygous dynein mutants can live up to two years and therefore make the design of longitudinal studies possible. Altogether, this mouse model provides dynein researchers an opportunity to work towards establishing the link between dynein mutations, dynein dysfunction and the onset and progression of disease.
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Date Issued: 2018
Identifier: CFE0007088, ucf:51956
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007088

Title: Novel Cytokine Signaling and Molecular Therapeutic Strategy in Pancreatic Cancer.
Creator: Gitto, Sarah, Altomare, Deborah, Khaled, Annette, Zhao, Jihe, Copik, Alicja, Masternak, Michal, University of Central Florida
Abstract / Description: Pancreatic ductal adenocarcinoma (PDAC) is highly chemo-resistant and has a five year survival rate of (
Show morePancreatic ductal adenocarcinoma (PDAC) is highly chemo-resistant and has a five year survival rate of (<)8%. Risk factors of pancreatic cancer, such as chronic pancreatitis, help to elicit a pro-tumor immune response, and highly fibrotic environment that promotes tumorigenesis. To study how chronic pancreatitis promotes cancer initiation, traditional KRasG12D mice and double mutant Akt1Myr/KrasG12D mice were used to model microenvironment changes. Akt1Myr/KrasG12D mice were more susceptible to chronic tissue damage, accelerated tumor development and metastatic disease. These mice exhibited histological changes consistent with immune cell privilege, where M2 macrophages and non-cytotoxic eosinophils were co-localized with fibrotic regions. IL-5 expression was up regulated in pancreatic cells undergoing acinar to ductal metaplasia and then diminished in advanced lesions. Tumor cells treated with IL-5 exhibit increased migration and activation through STAT5 signaling. Collectively, the results suggest that eosinophils, which are responsive to IL-5, are key mediators in the pancreatic environment subjected to chronic inflammation and injury.Current therapeutics fall short in increasing patient survival. There remains an urgent need for innovative treatments and thus we tested difluoromethylornithine (DFMO) in combination with a novel polyamine transport inhibitor, Trimer44NMe, against Gemcitabine-resistant PDAC cells. Prior clinical failures when targeting polyamine biosynthesis with DFMO monotherapy may be due to tumor escape via an undefined polyamine transport system. In pancreatic tumor cells DFMO alone and with Trimer44NMe significantly reduced PDAC cell viability by inducing apoptosis or cell cycle arrest. In vivo orthotopic PDAC growth with DFMO treatment resulted in decreased c-Myc expression, a readout of polyamine pathway dysfunction. Moreover, dual inhibition significantly prolonged survival of tumor-bearing mice, and increased M1 macrophage infiltration and reduced FoxP3 expression. Collectively, these studies demonstrate that targeting polyamine pathways in PDAC is a promising immunomodulating therapy that increases survival.
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Date Issued: 2017
Identifier: CFE0007283, ucf:52168
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007283

Title: Chaperonin Containing TCP1 (CCT) as a Target for Cancer Therapy.
Creator: Carr, Ana, Khaled, Annette, Altomare, Deborah, Tigno-Aranjuez, Justine, Fernandez-Valle, Cristina, University of Central Florida
Abstract / Description: Treatments for aggressive cancers like triple negative breast cancer (TNBC) and small-cell lung cancer (SCLC) have not improved and remain associated with debilitating side effects. There is an unmet medical need for better, druggable targets and improved therapeutics. To this end, we investigated the role of Chaperonin-Containing TCP1 (CCT), an evolutionarily conserved protein-folding complex composed of eight subunits (CCT1-8), in oncogenesis. Our laboratory was the first to report that the...
Show moreTreatments for aggressive cancers like triple negative breast cancer (TNBC) and small-cell lung cancer (SCLC) have not improved and remain associated with debilitating side effects. There is an unmet medical need for better, druggable targets and improved therapeutics. To this end, we investigated the role of Chaperonin-Containing TCP1 (CCT), an evolutionarily conserved protein-folding complex composed of eight subunits (CCT1-8), in oncogenesis. Our laboratory was the first to report that the CCT2 subunit is highly expressed in breast cancer and could be therapeutically targeted. To determine whether CCT is a marker of disease progression in other cancers, we analyzed CCT2 gene expression in liver, prostate and lung cancer, using publicly available genetic databases, and confirmed findings by assessing CCT2 and client proteins, like STAT3, in tumor tissues by immunohistochemistry. We found that CCT2 was high in all cancers, especially SCLC, and correlated with decreased patient survival. We tested CT20p, the peptide therapeutic developed by our laboratory to inhibit CCT, on SCLC and primary lung cells, finding that CT20p was only cytotoxic to SCLC cells. Since SCLC currently lacks targeted therapeutics, our work yielded a new targeted agent that could improve lung cancer mortality. To establish a mechanism of action for CT20p, we partially knocked out CCT2 in TNBC cells, which decreased tumorigenicity in mice and reduced levels of essential proteins like STAT3. To confirm, we overexpressed CCT2 in non-tumorigenic cells and conferred tumor-like characteristics such as increased migration and elevated STAT3. These studies positioned us to develop and validate a strategy for discovery of new small molecule inhibitors of CCT. We thus advanced the field of cancer research by demonstrating that CCT could have diagnostic potential for cancers, such as SCLC and TNBC, that are a significant cause of human death and showed that targeting CCT is a promising therapeutic approach.
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Date Issued: 2017
Identifier: CFE0007280, ucf:52191
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007280

Pancreatic Cancer (4)	+ -
Schwann cell (3)	+ -
breast cancer (3)	+ -
AKT (2)	+ -
KLF8 (2)	+ -

Pancreatitis (2)	+ -
cytoskeleton (2)	+ -
merlin (2)	+ -
ovarian cancer (2)	+ -
17-alpha Estradiol (1)	+ -
17?-E2 (1)	+ -
Aging (1)	+ -
Akt (1)	+ -
Akt1 (1)	+ -
Ames dward mice (1)	+ -
Angiogenesis (1)	+ -
ApoB (1)	+ -
Apoptosis (1)	+ -
Azelaic acid (1)	+ -
Biotechnology (1)	+ -
CRISPR/Cas9 (1)	+ -
CT20p (1)	+ -
CXCL12 (1)	+ -
CXCR4 (1)	+ -
Cancer (1)	+ -
Cerium Oxide Nanoparticles (1)	+ -
Charcot-Marie-Tooth Disease (1)	+ -
DFMO (1)	+ -
Diabetes (1)	+ -
Diabetes Mellitus (1)	+ -

ETD Collection (19)	+ -
Honors Collection (5)	+ -

University of Central Florida (24)	+ -
Altomare, Deborah (21)	+ -
Khaled, Annette (11)	+ -
Zhao, Jihe (8)	+ -
Masternak, Michal (6)	+ -

Estevez, Alvaro (4)	+ -
Fernandez-Valle, Cristina (4)	+ -
Lambert, Stephen (4)	+ -
Altomare, Deborah A. (3)	+ -
Siddiqi, Shadab (3)	+ -
Kim, Yoon-Seong (2)	+ -
King, Stephen (2)	+ -
Albury, Toya (1)	+ -
Baker, Cheryl (1)	+ -
Bassiouni, Rania (1)	+ -
Basu, Sambuddha (1)	+ -
Bossy-Wetzel, Ella (1)	+ -
Carr, Ana (1)	+ -
Chakrabarti, Ratna (1)	+ -
Cheung, Henley (1)	+ -
Clay, Ryan (1)	+ -
Cline, Kathryn (1)	+ -
Copik, Alicja (1)	+ -
Ebert, Steven (1)	+ -
Fuse, Marisa (1)	+ -
Gitto, Sarah (1)	+ -
Hogan, Frederick (1)	+ -
Kedarinath, Kritika (1)	+ -
Lessans, Spencer L (1)	+ -
Li, Tianshu (1)	+ -

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