1.Mechanisms Of Synergistic Antitumor Effct Of Panobinostat With Overexpressed HepaCAM In Prostate Cancer 2.HepaCAM Induces Cell Apoptosis Through PI3K-Akt/AR/DDR Pathways In Prostate Cancer

Objective : To study the reversing effect of Panobinostat on the expression of tumor suppressor gene hepa CAM and its synergistic inhibitory effect with hepa CAM on the growth of prostate cancer cells.Methods:PC3 and LNCap cells cultured in vitro were treated with Panobinostat at different concentrations and the effect of Panobinostat on cell proliferation was detected by MTT assay, followed by the expressio n changes of hepa CAM, HDACs, and the acetylation of lys9 of histone H3 detected by RT-PCR and Western blot. Then after the cells were treated with different factors, cell proliferation activity was detected by MTT assay, cell cycle change was detected by flow cytometry, and gene expressions of cell cycle regulating factors Cyclin D1 and PCNA were detected by RT-PCR and Western blot.Results:The inhibitory effect of Panobinostat on the growth of PC3 and LNCap cells was positively correlated to its concentration and duration. The expression levels of hepa CAM m RNA, its protein, and intranuclear Ac-H3K9 protein were increased, while that of both m RNA and protein of HDAC1, HDAC3, and HDAC4 were decreased when the concentration of Panobinostat increased; Cell growth was significantly inhibited in both the adenovirus-hepa CAM alone group and the Panobinostat alone group, with an inhibition rate increased along with the prolonged action time. This inhibition became even particularly noticeable when the two were combined, with a difference of statistical significance(P<0.05); the percentage of cells in S phase was significantly higher by the combined treatment compared with ad-hepa CAM alone and Panobinostat alone, respectively, with statistically significant differences(P<0.05). This combination could further downregulate the m RNA and protein expressions of cyclin D1 and PCNA, and the difference was statistically significant(P<0.05).Conclusion:Panobinostat may enhance the acetylation of lys9 of histone 3 and reverse the hepa CAM expression through its inhibitory effect on HDACs activity in PCa cells; hepa CAM-expressed adenovirus combined with Panobinostat may synergistically inhibit the growth of PCa cells, via a potential mechanism associated with the down-regulation of the expression of Cyclin D1 and PCNA.Objective:To investigate the function of hepa CAM in the apoptosis of prostate cancer cell and its molecular mechanism.Methods:PC3 and LNCap cells cultured in vitro were treated with hepa CAM-overexpressed adenovirus and the ability of apoptosis in prostate cancer cell was detected by The flow cytometry(FCM) and Hoechst 33258 kit, followed by the expression changes of Caspase family signal molecules(Procaspase8,cleaved caspase3 and cleaved caspase9) and DNA damage markerγ-H2 AX and DNA damage response(DDR) marker p-ATM detected by Western Blot. Then after the cells were treated with different activator and inhibitor of AR and PI3K-Akt pathways, gene expressions of AR and PI3K-Akt-pathways-regulated factors were detected by Western blot. cell apoptosis ability was detected by FCM and Caspase family molecules, cell cycle change was detected by flow cytometry, and DNA damage marker γ-H2 AX and DDR marker p-ATM were detected by Western Blot as well.Results: Compared with blank and Ad-GFP group, Ad-hepa CAM group exacerbated DNA damage, receded DNA damage repair response, promote cell apoptosis in prostate cancer. Hepa CAM regulated the expression of DDR pathway signals and apoptosis-related molecular and cell number change of apoptosis via PI3K- Akt and AR pathway signals.Conclusion: Hepa CAM may affect AR-mediated DDR pathway and cell apoptosis through PI3K-Akt pathway in prostate cancer. Therefore, joint target to PI3K-Akt and AR pathway may become a new way for prostate cancer therapy; Hepa CAM may act as a potential molecular target for early diagnosis and treatment of prostate cancer.