| Prostate cancer, which derives from prostate epithelial cells, is the second most lethal cancer in U.S. and European countries. Recently, it was estimated that about660thousand cases were diagnosed, and38%of them died of this disease each year. Therefore, studies on prostate cancer are of great significances.Hsp70proteins are oversepressed in many types of tumors. This overexpression of Hsp70is often correlated with tumor malignancy, and progression, poor prognosis and presence of metastasis. The overexpression of Hsp70induces cell transformation. Thus, Hsp70provides the protections of cells from apoptosis and necrosis induced by chemotherapeutic or other stress stimuli. In fact, depletion of Hsp70can cause apoptosis. In prostate cancer, Hsp70has a higher expression level, which reduces sensitivity of cells to a variety of anticancer agents. So far, researches related to Hsp70have been mostly concentrated on the fuctions of molecular chaperone, by contrast, and its regulations in prostate cancer still remain unclear. The purpose in the study was to determine the roles of Hsp70-1in mutual regulation of AR in prostate cancer, as well as more functions of Hsp70-1in prostate cancer by focusing on Hsp70-1in regulation of c-Fos.This thesis was divided into several parts as following:First of all, the eukaryotic vector expressed Hsp70-l gene was transfected into LNCaP cells, and we finally established LNCaP-Hsp70-1cell lines by G418selection. RT-PCR, Q-PCR, Western blot, siRNA interference and MTT were carried out to study the effects of Hsp70-1on AR and its signaling pathway under the conditions of overexpressed Hsp70-1. The wild type LNCaP was set as positive control, and some genes of AR signal pathway were used as positive markers to show the regulation of Hsp70-1. The result indicated that overexpression of Hsp70-1can increase the expressions of AR, and enhance the AR’s transcriptional level. Also the Hsp70-1activates or increased the expression of marker genes correlated with prostate cancer. However, while Hsp70-1was treated with inhibitors or knock-down by siHsp70-1, the functions above will be reduced or disappeared.Secondly, in order to study the regulation of AR on Hsp70-1, we created the LNCaP-AR cell lines using the methods similarily with LNCaP-Hsp70-1. RT-PCR, Q-PCR, Western blot, siRNA interference and ChIP methods were used to find out the relations between AR and Hsp70-1. The result indicates that AR has promoted expression of Hsp70-1by affecting directly the promoter of Hsp70-1, and this effect can be decreased while the siAR was treated in cells. Finally, we found that Hsp70-1adjusted c-Fos expression. c-Fos is described as an important oncogene in progression of prostate cancer. Based on datas obtained, we knew that Hsp70-1did regulate c-Fos and affect Hsfl and Hsf2. Hsf2miht bind with the promoter of c-Fos. However, the inconsistent regulation of AR on c-Fos was unknown in detail in PC-3and LNCaP cells, we need further evidence to discover the interactions.In conclusion, Hsp70-1interacted with AR in prostate cancer. And it was proved as a potential new target during the research of prostate cancer. In view of its function and structure, we hope to develop safe and efficient anti-Hsp70-1medicines. Meantime, our study presents a new method for the research and has a significant advising for the cancer therapy.
|
PDF Full Text Request