Serum concentrations of adipokines in men with prostate cancer and benign prostate hyperplasia

Obesity and prostate cancer are related, but the causal relationship remains unknown. The aim of the study was to compare concentrations of leptin, adiponectin and chemerin in patients with prostate cancer and benign prostate hyperplasia and to examine associations of the adipokines with the grade of prostate cancer, interleukin-6 (IL-6), insulin resistance and anthropometric and metabolic variables.

The study group consisted of 140 men divided into two groups: I- prostate cancer (n=74) and II- with benign hyperplasia (n=66). Serum leptin, adiponectin, chemerin, IL-6 and metabolic profile were measured. Considering histological differentiation prostate cancer patients were divided into 3 subgroups: well differentiated (Gleason score ≤ 6), moderately differentiated subgroup (Gleason 7), and poorly differentiated (Gleason ≥8).

There were no differences between groups in BMI, waist circumference, HOMA-I, serum levels of total cholesterol, glucose, triglycerides, adiponectin, leptin and chemerin. However, the concentrations of PSA, leptin-to-adiponectin ratio and IL-6 were significantly higher in cancer group compared with benign hyperplasia group. In the poorly differentiated cancer subgroup, subjects had higher PSA, leptin, chemerin, IL-6 and triglycerides concentrations. Overweight and obese men with prostate cancer were more likely to have moderately or poorly differentiated cancer than those with normal BMI. In the all men serum adiponectin was significantly correlated with HOMA-I, BMI, glucose, triglycerides, cHDL. There were significant correlations between leptin and BMI, HOMA-I, waist, glucose, triglycerides and cHDL. Among all the participants we observed associations between chemerin and waist as well as triglycerides. In prostate cancer patients chemerin correlated with IL-6 and leptin. We measured significant positive correlations between Gleason score and chemerin and leptin concentrations. There was a positive correlation between adiponectin and PSA levels in all men, as well as in cancer group.

Leptin-to-adiponectin ratio and IL-6 were elevated in men with prostate cancer. Leptin, chemerin and IL-6 were associated with Gleason score. The relationships between leptin, chemerin and IL-6 were dependent on each other. Overweight and obese men had a higher Gleason score.