Autophagy Markers p62, LC3II and Beclin1 Correlate with Clark Levels in Melanoma Tumors

Abstract BackgroundThe prognosis of melanoma depends on early diagnosis and timely treatment. Autophagy as a mechanism of degradation/recycling of cellular debris, has potential to be evaluated as prognostic biomarker in current research. MethodsIn this study, ATG5 and Beclin 1 gene expression in different Clark levels of melanoma were evaluated in a retrospective study of 10 years in the cancer institute of Tehran, Iran. The autophagy activity and the correlation with clinicopathological data were also investigated in a tissue microarray series of 52 melanomas after immunohistochemical staining for the autophagy-associated proteins p62, LC3II and Beclin1. The possibility of autophagy biomarkers were assessed by ROC curve analysis.ResultsThe patterns of ATG5 and Beclin1 gene expression are different. While ATG5 was increased in the early stage and then decreased as the stage was progressed in comparison to tumor margin, the Beclin1 expression was decreased and not altered during tumor progression. However, Beclin1 expression at the protein level was increased with tumor progression. The expression of LC3II was also raised while the p62 levels were declined as the tumor progressed, suggesting an increased autophagy activity in melanoma patients. Melanoma ulceration was positively correlated with Beclin 1 and LC3II expression and inversely correlated with p62 (p<0.05). Autophagy markers expression did not significantly correlate with melanoma mitotic rate and thickness. ConclusionsAutophagy is a potential prognostic factor in the early stage of melanoma and could be considered as a therapeutic target.