Expression of IL-6 and TNF-α in benign prostatic hyperplasia combined with histological inflammation

Abstract

Objective: To detect the expression of TNF-α and IL-6 in simple benign prostatic hyperplasia (BPH) and BPH combined with prostatitis, and to evaluate the effect of inflammation of the development and progression of BPH.

Methods: Specimens of 90 patients with BPH underwent transurethral resection of prostate (TURP) were obtained. All specimens were divided histologically by HE staining into group of 35 cases of simple BPH (A group) and group of 55 cases of BPH combined with prostatitis (B group). Proteins levels of TNF-α and IL-6 were examined by immunohistochemistry. All patients’ clinical indicators including PSA, prostate volume, age, urinary flow rate were recorded, and all patients were diagnosed as BPH by pathology.

Results: All patients of B group were found combined with chronic prostatitis. The constituent ratio was 61%. Patients’ prostate volume and PSA of B group were significant higher than A group (p < .05), but there were no significant differences in urine flow rate and patients’ age (p > .05). As compared with A group, the expression of TNF-α and IL-6 significantly increased in B group (p < .05). The results of analysis were as follows: there existed a moderate correlation between prostate volume and patients’ age (r = 0.430, p < .001); there existed a moderate correlation between prostate volume and the degree of inflammation (r = 0.610 and r = 0.609, p < .01); there existed a moderate correlation between PSA and the degree of inflammation (r = 0.572 and r = 0.487, p < .01); there was not significant correlation between PSA and patients’ age (r = 0.065, p > .1); controlling influence of the age factor by partial correlation analysis, there was still a significant correlation between the prostate volume and level of inflammation.

Conclusions: Most BPH patients are combined with prostatitis especially chronic inflammation. TNF-α and IL-6 are two-proinflammation cytokines, which obtain high expression in the prostate tissue combined with histological inflammation. Patients’ prostate volume and PSA of BPH combined with prostatitis are significantly higher than those of simple BPH. However, there are no significant differences in urine flow rate and patients’ age. These two cytokines may play an important part in promoting BPH and secretion of PSA.