Differences and Relationships between Morphometric Parameters and Zinc Content in Nonhyperplastic and Hyperplastic Prostate Glands

Abstract

Aims: To clarify the changes in morphometric parameters and contents of zinc (Zn) and in the relationship between these characteristics in normal and hyperplastic human prostates, a quantitative morphometry and energy-dispersive X-ray fluorescence analysis was performed. Methodology: Samples of the human prostate of mass under 30 g were obtained from randomly selected autopsy specimens of 35 men (European-Caucasian aged 40-87 years) who died mainly from trauma. All prostate glands were divided into two portions, each with an anterior-posterior cross-section: one tissue portion was reviewed by an anatomical pathologist while the other was used for the Zn mass fraction measurement. After preliminary histological investigation the subjects were divided into a control group (n=24) and a benign prostatic hyperplasia (BPH) group (n=11). The mean percent volume of the stroma (S), glandular epithelium (E), glandular lumen (L) and glandular component (GC=E+L) were determined, and the mean ratios of percent volumes (S/E, S/GC, and E/L) were calculated for each prostate specimen. Results: Increases in E (33.6% vs 26.7%) and GC (52.3% vs 44.4%) and also a decrease in S (47.7% vs 55.6%), S/E ratio (1.53 vs 2.31) and S/GC ratio (0.97 vs 1.40) were observed, when values for Zn mass fraction in the earliest stage of BPH were compared with normality. A significant positive correlation between Zn and L (r = 0.65, P≤0.001) and between Zn and GC (r = 0.45, P≤0.05) and also a negative correlation between Zn and S (r = - 0.45, P≤0.05), between Zn and E/L ratio (r = - 0.63, P≤0.001), and between Zn and S/GC ratio (r = - 0.42, P≤0.05) was seen in histologically normal prostate tissue. A negative correlation between Zn and S and a positive correlation between Zn and L disappeared in the earliest stage of hyperplastic change. It means that a homeostatic control of Zn level in the histological structures of prostate tissue was partially destroyed. Conclusion: For the first time it was quantitatively shown that BPH begins from the excessive proliferation of the glandular epithelium and that the Zn redistribution in the histological structures of prostate tissue is a pathogenetic factor of the disease.