MOTS-c Peptide Expression Patterns Uncovered in Human Adrenal Gland Tumors

The mitochondrial-derived peptide MOTS-c plays a crucial role in metabolic regulation and cellular stress responses. Adrenal tumors, which arise in the adrenal glands (small glands above the kidneys), are a diverse group ranging from benign adenomas to aggressive carcinomas and neuroendocrine pheochromocytomas. Despite their varied clinical behaviors, current diagnostic and prognostic markers for these tumors are often insufficient. This study addresses the critical knowledge gap regarding the specific expression patterns of MOTS-c within different types of human adrenal tumors and its potential implications for disease characterization.

The study revealed distinct MOTS-c expression patterns across different adrenal tumor types. MOTS-c protein levels were significantly downregulated by 65% in adrenal cortical carcinomas compared to normal adrenal tissue (p<0.001). In contrast, benign adrenal cortical adenomas showed a more modest 15% reduction in MOTS-c expression (p=0.04 vs. normal tissue). Interestingly, pheochromocytomas, tumors of the adrenal medulla, exhibited a significant 2.1-fold increase in MOTS-c expression compared to both normal tissue and cortical tumors (p<0.01). mRNA analysis largely mirrored these protein findings, with MOTS-c mRNA levels showing similar trends. > The most striking finding was the profound 65% decrease in MOTS-c protein expression specifically within aggressive adrenal cortical carcinomas, suggesting a potential role in tumor progression and malignancy.