| Background and purpose:Prostate cancer is one of the most common malignant tumor of men-Castrated by surgery or drugs is the main treatment of advanced prostate cancer,but most of the patients within 2 years after the deprivation therapy change to castration resistant prostate cancer(castration-resistant prostate cancer,CRPC).Vivek’s research which published in Cell shows:Glucocorticoid receptor(GR)will be activated after castration treatment,the biological effect through combined with target genes of androgen receptor(AR),but this study did not interpret the target gene activation and biological effect of GR itself.This study we aims to explore the the role of GR target genes regulate of metabolism in CRPC.Methods:1.Predict target genes of transcription factors GR.In prostate cancer gene database Taylor database,use Kaplan Meier-plots analysis target genes of GR,and selecte metabolism related genes as the research object;Use the same database analysis glycerol 3 phosphate dehydrogenase 1(GPD1)expression levels and the correlation of the clinical pathological characteristics and prognosis of prostate cancer2.Prostate cancer cell lines were transfected with lentivectors to stably overexpressing or knocking down the GR and GPD1.The expression of GPD1 was verified in transfected GR cell lines,and the regulation of GR on GPD1 was further verified by CHIP-PCR technique.Cell experiment analysis the function and metabolism of GPD1 in prostate cancer cells in vitro.3.Subcutaneous xenograft tumor model was established by injecting DU145 cell lines aberrantly expressing GPD1 into the subcutaneous of castrated nude mices,evaluating the in vivo effects induced by GPD1.4.Immunohistochemistry(IHC)analysis was performed to evaluate the GPD1 expression pattern in tissue microarray including 50 human PCa samples and 30 adjacent benign prostate tissues.Results:1.The total target gene of GR is 114 by transcription factor prediction.2.The target genes of GR were analyzed by Taylor dataset use Kaplan Meier-plots analyzes,results that GPD1 related to biochemical recurrence of prostate cancer(P = 0.015),which plays a key role in the metabolism.Further analysis showed that the GPD1 expression level in prostate cancer were obviously upregulated(P =0.017)and with with high Gleason scor(P<0.001),are closely associated with metastatic survival(P = 0.018).3.Vitro experiments showed that GPD1 protein levels falling in GR knockout prostate cancer cell lines.The results of CHIP-PCR showed that the expression of GPD1 in the experimental group was significantly higher than that in the control group(Fold change=2.73 in LNCaP and 3.12 in DU145).Cell function experiment show that proliferation ability of GPD1 overexpression of DU145 and LNCaP cell lines increase significantly contrast to control group,lactic acid increased obviously also(P<0.05).4.The DU145 cells stably expressing GPD1 formed significantly bigger tumor nodules and remarkably slowed tumor xenografts growth compared with the controls in castrated nude mice(P<0.05).5.Tissue microarray immune staining analysis showed the positive expression rate of S6K1 protein in PCa clinical samples was significantly higher than that in adjacent benign tissues(P<0.001)Conclusion:1.GR raised the expression of GPD1 in prostate cancer,promote lactic acid generated,effecting the metabolism of tumor.2.GPD1 obviously increased in prostate cancer,its expression was positively correlated with the malignant degree of prostate cancer,GPD1 respectively could serve as an independent factor for predicting the risk of BCR and metastasis after radical prostatectomy.GPD1 is an important promote cancer gene in prostate cancer.3.GR-GPD1 axis partially illustrates the molecular mechanism of CRPC progression and represents a novel potential therapeutic target for CRPC treatment. |
PDF Full Text Request