Expression And Significance Of PIM Family Kinases In Prostate Cancer

Objective:①To systematacially study the expression of all three members of PIM family kinases in prostate cancer.②To evaluate the relationship between PIM family kinases mRNA expression and clinicopathological variables of PCa.③To investigate the hypothesis that PIM family kinases may play key roles in the occurrence and development of PCa through their kinase homology domain.Methods:PCa samples (n=160) and BPH tissues (n=100) were collected from patients undergoing prostatectomy and were diagnosed at the second hospital of Tianjin medical university between2000and2012and were retrieved for this study. None of the patients received preoperative hormonal therapy, chemotherapy and actinotheraphy. Three kinds of cell lines were applied in this research, including PCa cell lines PC3and LNCaP, as well as nontumorous prostatic epithelial cell lines RWPE-1. The mRNA expression of PIM kinases was measured in PCa tissues and benign prostatic hyperplasia (BPH) tissues by RT-qPCR. Western blot analysis was performed to detect PIM kinases protein expression in prostate cell lines, including RWPE-1, LNCaP and PC3. We studied the correlation between the relative expression of PIM mRNA and clinicopathological parameters to evaluate its clinical significance.Results:①Pim-1、Pim-2and Pim-3mRNA levels in PCa tissue were all obviously higher than that in the BPH tissue(P<0.05).②All three members of PIM kinases protein level in LNCaP group and PC3group were both significantly higher than those in RWPE-1group(P<0.05).③The upregulation of three PIM mRNA in PCa tissues were correlated with the higher level of preoperative PSA (P<0.05), the higher Gleason score (P<0.05), the positive lymph node metastasis (P<0.05), the pathological stage (P<0.05) and the positive perineural invasion (P<0.05).④The three PIM mRNA expression were not related to age, seminal vesicle invasion, and surgical margin status (P>0.05).⑤PIM family kinases were significantly associated with PSA biochemical relapse (P<0.05).Conclusion:①Expressions of all three PIM kinases were upregulated in PCa compared with those in the BPH tissue and nontumorous prostatic epithelial cell.②Over-expression of PIM family kinases closely associated with the tumorigenesis and progression of prostate cancer.③PIM family kinases may play key roles in the occurrence and development of PCa through the kinase homology domain. PIM kinase domain could be an important breakthrough in the study of prostate cancer pathogenesis, and may become a potential therapeutic target for prostate cancer, but further studies are needed.