hTERT-Immortalized Prostate Epithelial and Stromal-Derived Cells: an Authentic In vitro Model for Differentiation and Carcinogenesis

Abstract

Prostate cancer is the most commonly diagnosed type of cancer in men, and there is no available cure for patients with advanced disease. In vitro model systems are urgently required to permit the study of human prostate cell differentiation and malignant transformation. Unfortunately, human prostate cells are particularly difficult to convert into continuously growing cultures. We report here the successful immortalization without viral oncogenes of prostate epithelial cells and, for the first time, prostate stromal cells. These cells exhibit a significant pattern of authentic prostate-specific features. In particular, the epithelial cell culture is able to differentiate into glandular buds that closely resemble the structures formed by primary prostate epithelial cells. The stromal cells have typical characteristics of prostate smooth muscle cells. These immortalized cultures may serve as a unique experimental platform to permit several research directions, including the study of cellcell interactions in an authentic prostate microenvironment, prostate cell differentiation, and most significantly, the complex multistep process leading to prostate cell transformation. (Cancer Res 2006; 66(7): 3531-40)

Immortalisation of Normal Human Urothelial Cells Compromises Differentiation Capacity

“…As shown in this study and reported elsewhere [24], urothelial cells, in common with prostate and small airway epithelial cells [29,30], were immortalised by hTERT over-expression alone. Prior to immortalisation, HU-hTERT populations displayed a lag-phase (p11-p13) characterised by reduced growth rates, without senescence or apoptosis.…”

Evaluation of Cellular Determinants Required for In Vitro Xenotropic Murine Leukemia Virus-Related Virus Entry into Human Prostate Cancer and Noncancerous Cells

“…All cells were originally obtained from the American Type Culture Collection and cultured in conditions as recommended by the supplier. The hTERT immortalized fibroblast (Pf179T), epithelial (Ep156T), and smooth muscle (Pm151T) cell lines were provided by V. Rotter (Weizmann Institute of Science, Israel) and cultured in conditions as recommended (19). The human primary (nonimmortalized) prostate fibroblast cells isolated from normal (Pt-N) or cancerous (Pt-C) tissues of prostate cancer patients were kind gifts of L. Chung (Emory University) and were cultured as described previously (39).…”

“…These methods were chosen because none of the commercially available polyclonal antibodies (2G8 from Abnova, N-19 from Santa Cruz, and ab13291 from Abcam) proved to be effective at detecting Xpr1 expression by Western blotting and/or IHC (data not show). We used a series of telomeraseimmortalized primary cell lines of the epithelial (Ep156T), smooth muscle (Pm151T), and fibroblast (Pf179T) origins that were previously derived from healthy human prostate glands (19). In addition, we also used nonimmortalized fibroblast cell lines, Pt-N and Pt-C, which were derived from benign and malignant prostate tissues, respectively (39), and the established primary prostatic epithelial PrEC cells (Lonza).…”

“…In addition, we also used nonimmortalized fibroblast cell lines, Pt-N and Pt-C, which were derived from benign and malignant prostate tissues, respectively (39), and the established primary prostatic epithelial PrEC cells (Lonza). Even though most of the telomerase-immortalized cell lines used in the present study, except for the Pf179T, have been characterized (19), we validated the cell-type origins of these and most other primary cell lines used in the present study by determining the expression of the specific protein markers by Western blot analysis with the appropriate antibodies. As expected, the epithelial cells (Ep156T and DU145) expressed cytokeratin 8 ( Fig.…”

Mutant p53R175H upregulates Twist1 expression and promotes epithelial–mesenchymal transition in immortalized prostate cells

“…To be able to evaluate the authentic role of p53 in prostate carcinogenesis, we assessed the effect of p53 mutation in EP156T-immortalized prostate epithelial cells. 9 Using this immortalized model, we could manipulate the cells in a controlled way and investigate individual lines with specific genetic alterations. The proliferative behavior of immortalized cells expressing either wt, inactivated or mutated p53 was analyzed, and genomic profiling was performed.…”