Clinical significance of the leptin and leptin receptor expressions in prostate tissues.
OBJECTIVE
To evaluate the expression of leptin and leptin receptor in benign prostatic hyperplasia (BPH) and prostate cancer (PCa), and to investigate whether they are associated with the development and progression of PCa.


METHODS
Immunohistochemical staining was performed to examine the expression of leptin and leptin receptor in BPH and PCa. PCa was divided into three groups: localized PCa, locally advanced PCa and metastatic PCa. The positive staining was identified and the percentage of the positive staining was graded. We also assessed the relationship between both the Gleason score and body mass index (BMI) and PCa.


RESULTS
The percentage of the leptin expression in PCa was significantly higher than that in BPH (P < 0.01). For the PCa group, the expressed levels of leptin showed a considerable correlation with localized PCa and metastatic PCa (P < 0.05). Leptin receptor, however, did not reveal a definite difference between BPH and PCa. The expression of leptin indicated a significant difference between well-differentiated PCa (Gleason score =or< 6) and poorly differentiated PCa (Gleason score 8?0) (P < 0.05). The relation between the leptin expression level in PCa and the BMI was not remarkable (P = 0.447).


CONCLUSIONS
Our results suggest that leptin might have a promoting effect on the carcinogenesis and progression of PCa.
Hoon Kim
Jung
J
Department of Urology, College of Medicine, Chung-Ang University, 65-207, Hankang-Ro 3 Ka, Yong-san Ku, Seoul 140-757, Korea.
Lee
Shin Young
SY
Myung
Soon Chul
SC
Kim
Young Sun
YS
Kim
Tae-Hyoung
TH
Kim
Mi Kyung
MK
D000368:Aged; D015415:Biomarkers; D015992:Body Mass Index; D018450:Disease Progression; D006801:Humans; D007150:Immunohistochemistry; D020738:Leptin / Q000096:biosynthesis*; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D011467:Prostate / Q000378:metabolism*; D011470:Prostatic Hyperplasia / Q000378:metabolism* / Q000473:pathology; D011471:Prostatic Neoplasms / Q000378:metabolism* / Q000473:pathology; D054411:Receptors, Leptin / Q000096:biosynthesis*
D015415:Biomarkers; D020738:Leptin; D054411:Receptors, Leptin