The Expression Of Neurotensin And Its Receptor In Androgen-independent Prostate Carcinoma

Prostate cancer is the most frequently diagnosed cancer and the second leading cause of cancer death in the United States and Europe. At present, the incidence of prostate cancer, is far lower than western countries, but shows a significant growth trend in china. Most of primary prostate cancer is androgen dependent prostate cancer(ADPC), about80%of which develops androgen independent prostate cancer(AIPC) after endocrine therapy. Therefore, the research on AIPC’s occurrence and progress may challenge the way we combat prostate cancer, and allow the development of new and better therapies by targeting given element.Part I NT and its receptor expression in ADPC orthotopic animal model Objective:To develop and demonstrate androgen-dependent LNCaP prostate cancer orthotopic animal model. To study the NT, NTSR1and NTSR2expression in prostate cancer animal model.Methods:AIPC animal model was established by planting tumor tissue or undergoing surgical castration. Affymetrix microarray technology, reverse transcriptase PCR and Q-PCR were than carried out to compare the gene expressions of NT, NTSR1and NTSR2in prostate cancer tumor tissue specimens. Immunohistochemistry and ELLSA technology were finally performed to detect protein expression of AR, PSA, NT, NTSRi and NTSR2in three groups prostate cancer tumor tissue.Results:(1)Successfully established androgen-dependent LNCaP and an AIPC orthotopic animal model and the different growth characteristics of these two animal models were demonstrated and throught the detection of AR, testosterone, PSA, tumorgrowth curve and axillary tumor activities.(2) Affymetrix microarray results:the NT expression in AIPC group was5.10times higher than that in ADPC group; the NT expression in castrated3days group was0.33times lower than that in ADPC group.(3) RT-PCR results:the expression level of NT in AIPC group were1.41times higher than that in ADPC group (P<0.01); the expression level of NT in castrated3days group were0.78time lower than that in ADPC group (P<0.05); the expression level of NTSRi in AIPC group were0.74time lower than that in ADPC group (P<0.01); the expression level of NTSR1in castrated3days group were1.74times higher than that in ADPC group(P<0.01); the expression level of NTSR1in AIPC group were0.16time lower than that in ADPC group; the expression level of NTSR2in castrated3days group were1.41times higher than that in ADPC group(P<0.05). 4) Q-PCR results:the expression level of NT gene in AIPC group were7.27times higher than that in ADPC group; the expression level of NT gene in castrated3days group were0.46time lower than that in ADPC group; the expression level of NTSR1gene in AIPC group were0.37time lower than that in ADPC group; the expression level of NTSR1gene in castrated3days group were2.48times higher than that in ADPC group; the expression level of NTSR2gene in AIPC group were0.45time lower than that in ADPC group; the expression level of NTSR2gene in castrated3days group were7.26times higher than that in ADPC group.(5)Immunohistochemistry results:There was statistical signicance(P<0.01) comparing NT expression in castrated3days group, ADPC group and AIPC group; NTSR1expression in these three group, had statistical signicance (P<0.05); comparing NTSR2expression in castrated3days group and AIPC group, there was statistical signicance (P<0.01).Conclusion:(1) We have successfully establish ADPC orthotopic animal model. This model can mimic the procession of clinical prostate cancer from ADPC to AIPC, and reflect the characteristics of the various prostate cancer stages.(2) The over-expressions of NT and NTSR1, NTSR2in AIPC group suggest that NT may be associated with prostate cancer tumor progression.(3):The high expressions of NTSR1and NTSR2in castrated3days group suggest their compesatory increase.PartⅡ NT and its receptor expression in human AIPC cancer tissueObjective:To study the NT, NTSR1and NTSR2expression in AIPC.Methods:RT-PCR and Q-PCR were used to compare the gene expressions of NT, NTSR1and NTSR2in human prostate cancer tumor tissue, and the differences in protein level were detected by immunohistochemistry.Results:(1)RT-PCR and Q-PCR results:the gene expression of NT showed various degrees of reduction in endocrine therapy group and increased in AIPC group; NTSRi and NTSR2gene expression increased in endocrine therapy group and decreased in AIPC group.(2)Immunohistochemistry results:comparing NT expression in endocrine therapy group, ADPC group and AIPC group, there was statistical signicance(P<0.01); comparing NTSR1expression in these three group, there was statistical signicance (P<0.05); comparing NTSR2expressions in endocrine therapy group and AIPC group, there was statistical signicance (P<0.01). Conclusion:(1) There is NT expression in the prostate cancer. NT may become a new biomarker of prostate cancer diagnosis.(2)The over-expressions of NT, NTSR1and NTSR2in AIPC group, suggest that NT may be associated with prostate cancer tumor growth; in the mean while, NTSR1and NTSR2may serve as a therapeutic target for prostate cancer in the future.(3) NTSR1and NTSR2high expression in the endocrine therapy group, suggest that NTSR1and NTSR2are increased compensatively during the endocrine therapy stage.