Role of Different Variants of Leptin Receptor in Human Adrenal Tumor Types

The aim of the study was to evaluate the diagnostic and prognostic significance of leptin receptor isoforms in adrenal tumors. In a single-center study, 96 patients (19 with adrenal cortical carcinoma and 77 with benign tumors) underwent an adrenalectomy. A total of 14 unaffected adrenal gland tissues from kidney donors were used as controls. Fasting blood samples were collected for laboratory tests, and mRNA expressions of leptin receptor isoforms were assessed by RT-qPCR. The study analyzed correlations between mRNA expressions and clinical data and measured NCI-H295R cell proliferation via a real-time cell analyzer. All adrenal lesions expressed leptin receptor isoforms. Significantly lower LepR1 expression was observed in carcinoma tissues than in adenomas and controls (<i>p</i> = 0.016). Expressions of LepR3&LepR6 were correlated with overall survival (<i>p</i> = 0.036), while LepR2&LepR4 and LepR5 expressions were inversely related to morning serum cortisol levels (<i>p</i> = 0.041). Leptin reduced NCI-H295R cell proliferation (<i>p</i> < 0.0001). The study highlights the diagnostic and prognostic significance of leptin receptor isoforms in adrenal tumors. Specifically, LepR1 may serve as a diagnostic marker for carcinomas, while LepR3&LepR6 have potential use as prognostic markers.