The relationship of HIF2 and the progression of PTEN-deficient mouse prostate tumors.

Abstract

30 Background: The hypoxia-inducible factor (HIF) transcription factor has already cemented its oncogenic role in the development of renal cell carcinoma (RCC). However, its role in the tumorigenesis of other solid tumors remains unspecificed. Our studies focus on a novel link between HIF and prostate carcinogenesis. Methods: Using both in vitro cell culture studies as well as in vivo studies (orthotopic xenograft and genetically engineered mouse models) we investigate the role of HIF in prostate cancer cell proliferation, invasion, and progression. Results: Both HIF1 and HIF2 appear to be necessary for the proliferation and invasion of prostate cancer cell lines in vitro. Preliminary analysis of a PTEN deficient mouse model of prostate cancer suggests that expression of a stabilized form of HIF2 promotes the development of a larger prostate tumor burden and a more aggressive histology (high grade prostate intraepithelial neoplasia [PIN] at earlier stages). Moreover, PTEN-deficient prostate tumors producing HIF2 are more proliferative and vascular and express increased levels of genes associated with epithelial to mesenchymal transition (EMT). Conclusions: There has been much interest in the role of angiogenesis and hypoxia in prostate cancer progression. Our preliminary data suggest that HIF2 is able to promote PTEN-deficient prostate cancer progression in mice by increasing proliferation, angiogenesis, and EMT. No significant financial relationships to disclose.