Nerve growth factor signaling following unilateral pelvic ;anglionectomy in the rat ventral prostate is age dependent

Benign prostatic hyperplasia （BPH） is a serious health concern and is an underlying cause of lower urinary tract symptoms （LUTS） in many men. In affected men, LUTS/BPH is believed to result from benign proliferation of the prostate resulting in bladder outlet obstruction. Postnatal growth of the prostate is controlled via growth factor and endocrine mechanisms. However, little attention had been given to the function of the autonomic nervous system in prostate growth and differentiation. Nerve growth factor （NGF） is a prostatic mitogen that has a trophic role in autonomic sensory end organ interaction. In this study, we examine how the autonomic nervous system influences prostate growth as a function of age by quantifying NGF in the rat ventral prostate （VP） after pelvic ganglionectomy. Unilateral pelvic ganglionectomy was performed on postnatal days 30 （P30）, 60 and 120 Sprague-Dawley rats in comparison to sham controls （n=39）. Semiquantitative RT-PCR, Western blotting and immunohistochemical analysis for NGF were performed on denervated, intact （contralateral side） and sham control VP 7 days after surgery. Ngf RNA expression was significantly increased in the denervated and intact hyperplastic VP. Western blotting showed age-dependent increases in NGF protein at P60 in the contralateral intact VP. NGF was localized in the nerves, basal cells and columnar epithelium of the prostatic ducts. Denervation causes age-dependent increases in NGF in the VP, which is a potential mechanism by which the autonomic nervous system may regulate prostate growth and lead to BPH/LUTS.

Prostate Volume Growth Rate Changes over Time:Results from Men 18 to 92 Years Old in a Longitudinal Community-based Study

Previous investigations have shown that changes in total prostate volume（TPV） are highly variable among aging men,and a considerable proportion of aging men have a stable or decreasing prostate size.Although there is an abundance of literature describing prostatic enlargement in association with benign prostatic hyperplasia,less is known about the appropriate age cut-off points for TPV growth rate.In this community-based cohort study,TPV was examined once a year in men who had consecutive health checkup,during a follow-up of 4 years.A total of 5058 men（age 18–92 years old） were included.We applied multiple regression analyses to estimate the correlation between TPV growth rate and age.Overall,3232（63.9%） men had prostate growth,and 1826（36.1%） had a stable or decreased TPV during the study period.The TPV growth rate was correlated negatively with baseline TPV（r= –0.32,P〈0.001）.Among 2620 men with baseline TPV 〈15 cm^3,the TPV growth rate increased with age（β=0.98,95% CI：0.77%–1.18%） only up to 53 years old.Among 2188 men with baseline TPV of 15–33.6 cm3,the TPV growth rate increased with age（β=0.84,95% CI,0.66%–1.01%） only up to 61 years old after adjusting for factors of hypertension,obesity,baseline TPV,diabetes mellitus and dyslipidemia.In this longitudinal study,the TPV growth rate increased negatively with baseline TPV,only extending to a certain age and not beyond.Further research is needed to identify the mechanism underlying such differences in prostate growth.

The effect of interleukin 6 on the growth of LNCaP and PC-3 prostatic carcinoma cells

Objective To investigate the effect of IL-6 on prostatic carcinoma cell lines, and differential effects on androgen-dependent and androgen-independent prostatic carcinoma cells. Methods The IL-6 producing capacities of LNCaP and PC-3 cells were determined, and effects of exogenous IL-6 and anti-IL - 6 antibodies on LNCaP and PC - 3 cells were examined. Results LNCaP produced a very small amount of IL-6, but PC-3 produced more, the concentraion of IL-6 being 190 pg/48 h per ml(1 × 106). The exogenous IL-6 inhibited LNCaP growth significantly,but had no obvious effect on PC -3 cells. Anti-IL-6 antibodies lowered PC-3 cells growth rate but had neutral effect on LNCaP. Conclusion PC-3 cells produces IL-6 massively in autocrine manner. IL-6 could be antagonized by anti-IL-6 antibodies,resulting in slowing PC-3 cells growth, and LNCaP cells growth could be inhibited by exogenous IL-6.7 refs,2 tabs.

Glucocorticoids suppress tumor angiogenesis and growth of prostate cancer

Hormone-refractory prostate cancer ( HRPC) sometimes is responsive to treatment with glucocorticoids, such as prednisolone, hydrocortisone and dexamethasone, but the underlying mechanisms are not well established. In a recent paper (Clin Cancer Res, 2006, 12:3003-3009), Yano et al. Hypothesized and confirmed that the therapeutic effect of glucocorticoids on HRPC is attributed to inhibition of angiogenesis. A prostate cancer cell line DU145 that expresses glucocorticoid receptor was used to study the effect of dexamethasone (Dex) on the expres-