Leptin and leptin receptor expressions in prostate tumors may predict disease aggressiveness?

Abstract

PURPOSE:The aim of this study was to evaluate the expression of leptin and its receptor in histological sections of prostate tumors, and their association with prognostic factors. METHODS:A total of 532 surgical specimens from prostate cancer were studied. After histopathological diagnosis, the samples were included in tissue microarrays containing cores from tumor and non-tumor (benign prostatic hyperplasia) areas. These were immunostained with anti-leptin and anti-leptin-receptor antibodies. Objective and subjective analyses were performed. Student's-t-test and ANOVA were used to compare mean values, and linear regression was used to evaluate the correlation between histological results and prognostic indicators. RESULTS:Leptin receptor expression was reduced in tumors with a positive surgical margin, urethral margin involvement, and seminal vesicles invasion. Further, there was a negative correlation between the expression of leptin receptor in tumor areas and the sum of prognostic factors, suggesting that leptin receptor may predict the aggressiveness of disease. CONCLUSION:Our findings suggest that leptin receptor expression is a potential prognostic factor for PCa. Further investigation is needed to support the use of leptin receptor as a novel biomarker, although leptin itself does not seem to predict the aggressiveness of prostate cancer.

Serum 17β-estradiol fails as a marker in identification of aggressive tumour disease in patients with localized prostate cancer

“…However, the effects of leptin remain controversial and unclear [28]. Long-term exposure of PC cells to leptin enhances their proliferation, migration and invasion, and leptin increases the leptin receptor expression and enhances prokinase B (Akt) phosphorylation constitutively, as postulated currently by Noda et al [29].…”

“…Since leptin is produced by adipocytes, the serum leptin level is higher in obese than in non-obese individuals [28]. However, the effects of leptin remain controversial and unclear [28].…”

Immunohistochemical analysis of adipokine and adipokine receptor expression in the breast tumor microenvironment: associations of lower leptin receptor expression with estrogen receptor-negative status and triple-negative subtype

“…Differences of least squares means were generated using multivariate mixed effects models controlling for BMI and menopausal status. Each model also mutually controlled for the other four biomarkers examined a Breast cancer subtypes were classified based on IHC expression of ER and PR, and overexpression or amplification of HER2 (by IHC or FISH) as reported in pathology records clinicopathologic features indicative of tumor progression or aggressiveness in other obesity-related cancers [58][59][60][61][62][63]. A study of colorectal cancer showed that downregulation of LEPR IHC expression was associated with aggressive tumor features (namely late stage, high grade) as well as with shorter survival time [61].…”

“…A study of colorectal cancer showed that downregulation of LEPR IHC expression was associated with aggressive tumor features (namely late stage, high grade) as well as with shorter survival time [61]. Osorio and colleagues [60] showed that while there was no significant association of LEP IHC expression with prostate tumor aggressiveness, quantitative IHC expression of LEPR was significantly lower in prostate tumors exhibiting prognostic factors indicative of aggressive phenotype (namely, urethral margin involvement, surgical margin involvement, and seminal vesicle involvement). Studies of thyroid cancer [58,59] have also shown that downregulation of LEPR was associated with increased risk of thyroid cancer recurrence and metastasis, particularly in the anaplastic thyroid cancer (ATC) subtype [59].…”

Dietary lipids and adipocytes: potential therapeutic targets in cancers

“…It is also found that in cocultures of colon cancer cells with adipocytes, the proliferative effect exerted by the adipocytes was leptin-dependent as mature adipocytes from leptin-deficient mice did not increase cancer cell proliferation but could be rescued by exogenous leptin administration [94]. However, controversial findings are also reported to suggest that leptin is not associated with increased carcinoma in situ of the breast [95] and is not correlated with prostate cancer incidence [96]. Adiponectin is another adipokine; it is negatively correlated with adiposity and has anticancer effects.…”