Medicine and Health Sciences Commons^™

Saturated Free Fatty Acids Induce Cholangiocyte Lipoapoptosis, Sathish Kumar Natarajan, Sally A. Ingham, Ashley M. Mohr, Cody J. Wehrkamp, Anuttoma Ray, Sohini Roy, Sophie C. Cazanave, Mary A. Smith, Justin L. Mott

Journal Articles: Biochemistry & Molecular Biology

Recent studies have identified a cholestatic variant of nonalcoholic fatty liver disease (NAFLD) with portal inflammation and ductular reaction. Based on reports of biliary damage, as well as increased circulating free fatty acids (FFAs) in NAFLD, we hypothesized the involvement of cholangiocyte lipoapoptosis as a mechanism of cellular injury. Here, we demonstrate that the saturated FFAs palmitate and stearate induced robust and rapid cell death in cholangiocytes. Palmitate and stearate induced cholangiocyte lipoapoptosis in a concentration-dependent manner in multiple cholangiocyte-derived cell lines. The mechanism of lipoapoptosis relied on the activation of caspase 3/7 activity. There was also a significant up-regulation …

Mastl Kinase, A Promising Therapeutic Target, Promotes Cancer Recurrence., Ling Wang, Vivian Q. Luong, Peter J. Giannini, Aimin Peng

Journal Articles: College of Dentistry

Mastl kinase promotes mitotic progression and cell cycle reentry after DNA damage. We report here that Mastl is frequently upregulated in various types of cancer. This upregulation was correlated with cancer progression in breast and oral cancer, poor patient survival in breast cancer, and tumor recurrence in head and neck squamous cell carcinoma. We further investigated the role of Mastl in tumor resistance using cell lines derived from the initial and recurrent tumors of the same head and neck squamous cell carcinoma patients. Ectopic expression of Mastl in the initial tumor cells strongly promoted cell proliferation in the presence of …

The Omega-3 Fatty Acid Docosahexaenoic Acid Attenuates Organic Dust-Induced Airway Inflammation., Tara M. Nordgren, Taylor D. Friemel, Art J. Heires, Jill A. Poole, Todd A. Wyatt, Debra J. Romberger

Journal Articles: Pulmonary & Critical Care Med

Workers exposed to organic dusts from concentrated animal feeding operations (CAFOs) are at risk for developing airway inflammatory diseases. Available preventative and therapeutic measures for alleviating dust-induced lung disease are inadequate. Because omega-3 fatty acids can mitigate inflammatory processes, we aimed to determine whether nutritional supplementation with the omega-3 fatty acid docosahexaenoic acid (DHA) could reduce the airway inflammatory consequences of exposures to organic dust. Aqueous extracts of organic dusts from swine CAFOs (ODE) were utilized. In DHA-pretreated human bronchial epithelial cells, lung fibroblasts, monocyte cell cultures, and precision-cut murine lung slices, we found that DHA pretreatment dose-dependently decreased ODE-induced …

Inhibition Of Rac1 Gtpase Sensitizes Pancreatic Cancer Cells To Γ-Irradiation., Y Yan, Ashley L. Hein, Asserewou Etekpo, Katrina M. Burchett, Chi Lin, Charles A. Enke, Surinder K. Batra, Kenneth Cowan, M Ouellette

Journal Articles: Radiation Oncology

Radiation therapy is a staple treatment for pancreatic cancer. However, owing to the intrinsic radioresistance of pancreatic cancer cells, radiation therapy often fails to increase survival of pancreatic cancer patients. Radiation impedes cancer cells by inducing DNA damage, which can activate cell cycle checkpoints. Normal cells possess both a G1 and G2 checkpoint. However, cancer cells are often defective in G1 checkpoint due to mutations/alterations in key regulators of this checkpoint. Accordingly, our results show that normal pancreatic ductal cells respond to ionizing radiation (IR) with activation of both checkpoints whereas pancreatic cancer cells respond to IR with G2/M arrest …

Unbiased Analysis Of Pancreatic Cancer Radiation Resistance Reveals Cholesterol Biosynthesis As A Novel Target For Radiosensitisation., Joshua J. Souchek, Michael J. Baine, Chi Lin, Satyanarayana Rachagani, Suprit Gupta, Sukhwinder Kaur, K Lester, D Zheng, S Chen, Lynette Smith, A Lazenby, Sonny L. Johansson, Maneesh Jain, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

BACKGROUND: Despite its promise as a highly useful therapy for pancreatic cancer (PC), the addition of external beam radiation therapy to PC treatment has shown varying success in clinical trials. Understanding PC radioresistance and discovery of methods to sensitise PC to radiation will increase patient survival and improve quality of life. In this study, we identified PC radioresistance-associated pathways using global, unbiased techniques.

METHODS: Radioresistant cells were generated by sequential irradiation and recovery, and global genome cDNA microarray analysis was performed to identify differentially expressed genes in radiosensitive and radioresistant cells. Ingenuity pathway analysis was performed to discover cellular pathways …

Novel Role Of Pancreatic Differentiation 2 In Facilitating Self-Renewal And Drug Resistance Of Pancreatic Cancer Stem Cells., Arokia P. Vaz, Moorthy P. Ponnusamy, Satyanarayana Rachagani, P Dey, Apar Kishor Ganti, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

BACKGROUND: Cancer stem cells (CSCs) contribute towards disease aggressiveness and drug resistance. Specific identification of CSC maintenance genes and targeting can improve the efficiency of currently available treatment modalities. Pancreatic differentiation 2 (PD2) has a major role in the self-renewal of mouse embryonic stem cells. In the present study, we investigated the role of PD2 in pancreatic CSCs.

METHODS: Characterisation of CSCs and non-CSCs from mouse models, pancreatic cancer cells and human tissues by CSC and self-renewal marker analysis using confocal assay. Effect of PD2 knockdown in CSCs (after gemcitabine treatment) was studied by immunoblot and apoptosis assays.

RESULTS: A …

Functional Proteomic Analysis Reveals The Involvement Of Kiaa1199 In Breast Cancer Growth, Motility And Invasiveness., Mohammad-Saeid Jami, Jinxuan Hou, Miao Liu, M L. Varney, Hesham Hassan, Jixin Dong, Liying Geng, J. Wang, Fang Yu, Xin Huang, Hong Peng, Kai Fu, Yan Li, Rakesh Singh, Shi-Jian Ding

Journal Articles: Pathology and Microbiology

BACKGROUND: KIAA1199 is a recently identified novel gene that is up-regulated in human cancer with poor survival. Our proteomic study on signaling polarity in chemotactic cells revealed KIAA1199 as a novel protein target that may be involved in cellular chemotaxis and motility. In the present study, we examined the functional significance of KIAA1199 expression in breast cancer growth, motility and invasiveness.

METHODS: We validated the previous microarray observation by tissue microarray immunohistochemistry using a TMA slide containing 12 breast tumor tissue cores and 12 corresponding normal tissues. We performed the shRNA-mediated knockdown of KIAA1199 in MDA-MB-231 and HS578T cells to …

Inhibition Of Rac1 Gtpase Sensitizes Pancreatic Cancer Cells To Γ-Irradiation, Y Yan, Ashley L. Hein, Asserewou Etekpo, Katrina M. Burchett, Chi Lin, Charles A. Enke, Surinder K. Batra, Kenneth Cowan, Michel M. Ouellette

Journal Articles: Biochemistry & Molecular Biology

Radiation therapy is a staple treatment for pancreatic cancer. However, owing to the intrinsic radioresistance of pancreatic cancer cells, radiation therapy often fails to increase survival of pancreatic cancer patients. Radiation impedes cancer cells by inducing DNA damage, which can activate cell cycle checkpoints. Normal cells possess both a G1 and G2 checkpoint. However, cancer cells are often defective in G1 checkpoint due to mutations/alterations in key regulators of this checkpoint. Accordingly, our results show that normal pancreatic ductal cells respond to ionizing radiation (IR) with activation of both checkpoints whereas pancreatic cancer cells respond to IR with G2/M arrest …