Expression Of Ob-R And STAT3 In Prostate Cancer Tissues And Its Significance

Background and Objective:Prostate carcinoma is the most common urinary tract tumor in western countries and its incidence in China also shows a rising trend year by year. Surgery or hormone therapy is the most effective treatment measures, but the measures are easy to recurrence and transfer. Prostate carcinoma seriously affects the urinary system cancer prognosis survival. The pathogenesis of PCa has not yet been clarified, and the level of regulation by multiple genes may be involved in many important aspects of the disease. This article was detected by immunohistochemistry leptin receptor (Ob-R) and signal transducer and activator of transcription 3 (STAT3) in prostate cancer (PCa), prostatic intraepithelial neoplasia (PIN) and benign prostatic hyperplasia (BPH) tissue Expression to explore the biological behavior and clinical significance.Materials and Method:We collected 41 cases of prostate cancer,22 cases of prostatic intraepithelial neoplasia and 25 cases of benign prostatic hyperplasia which were all confirmed by pathology specimens from prostate biopsy or surgery and from second hospital of Tianjin medical university in January 2008-December 2009. PCa patients'average age is 65 with a range of 51-73 years. According to Gleason grading system for histological grading of PCa,41 cases of prostate cancer can be divided into 12 cases of well-differentiated cancer(2 to 4 points),15 cases of moderately differentiated carcinoma(5 to 7 points) and 14 cases of poorly differentiated carcinoma(8 to 10 points). According to the 2002 American Association of Cancer(AJCC) TNM staging system in 41 patients with PCa were divided into two groups:18 cases of T1-T2 and 23 cases of T3-T4. PIN patients'average age is 64 with a range of 56-72 years. In the 22 cases of PIN, the low-level PIN have 10 cases and the senior PIN have 12 cases. BPH patients aged 51-79 years and meaned 66 years. All the patients were not received preoperative radiotherapy, chemotherapy or anti-androgen therapy. Staining steps were carried out according to kit instructions, and we choose positive prostate cancer histological section as positive control, with PBS replaced the antibody as negative control. The result were observed by light microscope, and buffy particles in cells were considered as positive cases. SPSS 11.5.0 software application was used for all analysis and statistical significance was defined as P values less than 0.05.Results:(1) In 41 cases of prostate cancer,37 patients showed positive expression of Ob-R, the positive rate was 90.24%; In 22 cases of prostatic intraepithelial neoplasia tissues,16 cases were positive, the positive rate was 72.73%; In the 25 cases of benign prostatic hyperplasia tissues, the expression were 14 cases, the positive rate was 56%. Three groups were compared pairwise. The difference of prostate cancer and benign prostatic hyperplasia group was statistically significant(P<0.01). The remaining pairwise comparison between groups were not statistically significant(P>0.05). As the increase of pathological grade, the positive expression rate of Ob-R in prostate cancer raised, well-differentiated cancer, moderately differentiated carcinoma and poorly differentiated cancers were positive rate:83.33%(10/12), 86.67%(13/15),100%(14/14). Pairwise comparisons among the three groups were not statistically different (P> 0.05). In the clinical stage of prostate cancer, the positive expression rate of Ob-R was 94.44%(17/18) in T1-T2 period and the T3-T4 period was 86.96%(20/23). Difference between the two groups does not make sense.(P>0.05). (2) In 41 cases of prostate cancer,36 patients showed positive expression of STAT3, the positive rate was 87.80%; In 22 cases of prostatic intraepithelial neoplasia tissues,18 cases were positive, the positive rate was 81.82%; In the 25 cases of benign prostatic hyperplasia tissues, the expression were 15 cases, the positive rate was 60%. Three groups were compared pairwise. The difference of prostate cancer and benign prostatic hyperplasia group was statistically significant(P<0.01). The remaining pairwise comparison between groups were not statistically significant(P>0.05). As the increase of pathological grade, the positive expression rate of STAT3 in prostate cancer was raised, well-differentiated cancer, moderately differentiated carcinoma and poorly differentiated cancers were positive rate:66.67% (8/12),93.33%(14/15),100%(14/14). By pairwise comparisons between the three groups, there is only significant difference between the well-differentiated and poorly differentiated group. In the clinical stage of prostate cancer, the positive expression rate of STAT3 was 88.89%(16/18) in T1-T2 period and the T3-T4 period was 86.96%(20/23). Difference between the two groups does not make sense.(P>0.05). (3) In the 37 cases that expressed Ob-R positively, there were 36 cases expressed STAT3. There were statistically significant correlation between the expression of Ob-R and STAT3 in PCa by the Spearman correlation analysis.Conclusion:(1) This study suggests that positive expression rate of Ob-R and STAT3 showed an increasing trend in BPH,PIN and PCa group, but the differences were only statistically significant between the BPH and PCa group. Comparisons between other groups were not statistically significant.(2) The expression of Ob-R in prostate cancer with clinical stage and patholofical grade was no clear relationship; The expression of STAT3 in prostate cancer was only matter with the pathological grade, but there was no relationship with clinical stage. (3) Ob-R may have cooperation with STAT3 in the process of molecular regulation of PCa via synergistic actions, promoting the occurrence and development of prostate cancer.