Medicine and Health Sciences Commons^™

Novel Pancreatic Cancer Cell Lines Derived From Genetically Engineered Mouse Models Of Spontaneous Pancreatic Adenocarcinoma: Applications In Diagnosis And Therapy., María P. Torres, Satyanarayana Rachagani, Joshua J. Souchek, Kavita Mallya, Sonny L. Johansson, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

Pancreatic cancer (PC) remains one of the most lethal human malignancies with poor prognosis. Despite all advances in preclinical research, there have not been significant translation of novel therapies into the clinics. The development of genetically engineered mouse (GEM) models that produce spontaneous pancreatic adenocarcinoma (PDAC) have increased our understanding of the pathogenesis of the disease. Although these PDAC mouse models are ideal for studying potential therapies and specific genetic mutations, there is a need for developing syngeneic cell lines from these models. In this study, we describe the successful establishment and characterization of three cell lines derived from two …

Microrna-200c Modulates The Expression Of Muc4 And Muc16 By Directly Targeting Their Coding Sequences In Human Pancreatic Cancer., Prakash Radhakrishnan, Ashley M. Mohr, Paul M. Grandgenett, Maria M. Steele, Surinder K. Batra, Michael A. Hollingsworth

Journal Articles: Biochemistry & Molecular Biology

Transmembrane mucins, MUC4 and MUC16 are associated with tumor progression and metastatic potential in human pancreatic adenocarcinoma. We discovered that miR-200c interacts with specific sequences within the coding sequence of MUC4 and MUC16 mRNAs, and evaluated the regulatory nature of this association. Pancreatic cancer cell lines S2.028 and T3M-4 transfected with miR-200c showed a 4.18 and 8.50 fold down regulation of MUC4 mRNA, and 4.68 and 4.82 fold down regulation of MUC16 mRNA compared to mock-transfected cells, respectively. A significant reduction of glycoprotein expression was also observed. These results indicate that miR-200c overexpression regulates MUC4 and MUC16 mucins in pancreatic …

The Tumor Suppressor Tere1 (Ubiad1) Prenyltransferase Regulates The Elevated Cholesterol Phenotype In Castration Resistant Prostate Cancer By Controlling A Program Of Ligand Dependent Sxr Target Genes., William J. Fredericks, Jorge Sepulveda, Priti Lai, John E. Tomaszewski, Ming-Fong Lin, Terry Mcgarvey, Frank J. Rauscher, S. Bruce Malkowicz

Journal Articles: Biochemistry & Molecular Biology

Castrate-Resistant Prostate Cancer (CRPC) is characterized by persistent androgen receptor-driven tumor growth in the apparent absence of systemic androgens. Current evidence suggests that CRPC cells can produce their own androgens from endogenous sterol precursors that act in an intracrine manner to stimulate tumor growth. The mechanisms by which CRPC cells become steroidogenic during tumor progression are not well defined. Herein we describe a novel link between the elevated cholesterol phenotype of CRPC and the TERE1 tumor suppressor protein, a prenyltransferase that synthesizes vitamin K-2, which is a potent endogenous ligand for the SXR nuclear hormone receptor. We show that 50% …

Impaired Expression Of Protein Phosphatase 2a Subunits Enhances Metastatic Potential Of Human Prostate Cancer Cells Through Activation Of Akt Pathway., P Pandey, Parthasarathy Seshacharyulu, Srustidhar Das, Satyanarayana Rachagani, Moorthy P. Ponnusamy, Y Yan, Sonny L. Johansson, K Datta, Ming-Fong Lin, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

BACKGROUND: Protein phosphatase 2A (PP2A) is a dephosphorylating enzyme, loss of which can contribute to prostate cancer (PCa) pathogenesis. The aim of this study was to analyse the transcriptional and translational expression patterns of individual subunits of the PP2A holoenzyme during PCa progression.

METHODS: Immunohistochemistry (IHC), western blot, and real-time PCR was performed on androgen-dependent (AD) and androgen-independent (AI) PCa cells, and benign and malignant prostate tissues for all the three PP2A (scaffold, regulatory, and catalytic) subunits. Mechanistic and functional studies were performed using various biochemical and cellular techniques.

RESULTS: Through immunohistochemical analysis we observed significantly reduced levels of PP2A-A …

Androgens Upregulate Cdc25c Protein By Inhibiting Its Proteasomal And Lysosomal Degradation Pathways., Yu-Wei Chou, Li Zhang, Sakthivel Muniyan, Humera Ahmad, Satyendra Kumar, Syed Mahfuzul Alam, Ming-Fong Lin

Journal Articles: Biochemistry & Molecular Biology

Cdc25C is a cell cycle protein of the dual specificity phosphatase family essential for activating the cdk1/Cyclin B1 complex in cells entering into mitosis. Since altered cell cycle is a hallmark of human cancers, we investigated androgen regulation of Cdc25C protein in human prostate cancer (PCa) cells, including androgen-sensitive (AS) LNCaP C-33 cells and androgen-independent (AI) LNCaP C-81 as well as PC-3 cells. In the regular culture condition containing fetal bovine serum (FBS), Cdc25C protein levels were similar in these PCa cells. In a steroid-reduced condition, Cdc25C protein was greatly decreased in AS C-33 cells but not AI C-81 or …

Marked Improvement Of Cytotoxic Effects Induced By Docetaxel On Highly Metastatic And Androgen-Independent Prostate Cancer Cells By Downregulating Macrophage Inhibitory Cytokine-1., M Mimeault, Sonny L. Johansson, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

BACKGROUND: Overexpression of macrophage inhibitory cytokine-1 (MIC-1) frequently occurs during the progression of prostate cancer (PC) to androgen-independent (AI) and metastatic disease states and is associated with a poor outcome of patients.

METHODS: The gain- and loss-of-function analyses of MIC-1 were performed to establish its implications for aggressive and chemoresistant phenotypes of metastatic and AI PC cells and the benefit of its downregulation for reversing docetaxel resistance.

RESULTS: The results have indicated that an enhanced level of secreted MIC-1 protein in PC3 cells is associated with their acquisition of epithelial-mesenchymal transition features and higher invasive capacity and docetaxel resistance. Importantly, …

Muc4 Overexpression Augments Cell Migration And Metastasis Through Egfr Family Proteins In Triple Negative Breast Cancer Cells., Partha Mukhopadhyay, Imayavaramban Lakshmanan, Moorthy P. Ponnusamy, Subhankar Chakraborty, Maneesh Jain, Priya Pai, Lynette M. Smith, Subodh M. Lele, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

INTRODUCTION: Current studies indicate that triple negative breast cancer (TNBC), an aggressive breast cancer subtype, is associated with poor prognosis and an early pattern of metastasis. Emerging evidence suggests that MUC4 mucin is associated with metastasis of various cancers, including breast cancer. However, the functional role of MUC4 remains unclear in breast cancers, especially in TNBCs.

METHOD: In the present study, we investigated the functional and mechanistic roles of MUC4 in potentiating pathogenic signals including EGFR family proteins to promote TNBC aggressiveness using in vitro and in vivo studies. Further, we studied the expression of MUC4 in invasive TNBC tissue …