Document Type: Original Research


1 Department of Biology, Parand Branch, Islamic Azad University, Parand, Iran

2 Department of Pathology, Tehran University of Medical Sciences, Tehran, Iran



Background & Objective: Malignant melanoma is the fatal cutaneous neoplasm which is curable by the early diagnosis. The expression of occludin protein which is an integral membrane protein is altered in an epithelial-to-mesenchymal transition. Although, recent studies provide sufficient evidence supporting the functional importance of occludin in cancer, the prognostic significance of occludin expression levels in melanoma remains obscure. The aim of this study was to determine occludin expression level and itscorrelation with clinicopathological features of the patients with melanoma. 
Methods: The occludin mRNA level was compared between paraffin-embedded tissues of 40 patients with melanoma and 10 subjects with normal skin. The quality and quantity of the RNA was determined and occludin expression level was measured using Real-time PCR and ∆∆CT computational technique.
Results: Theoccludin mRNA level reduced five-fold in the melanoma patients compared to the control group (P=0.000). No significant difference was observed between male and female cases (P=0.533). No significant correlation was observed between occludin mRNA level, mitotic count (P=0.252), and Breslow levels (P=0.171)
Conclusion: We can conclude that down-regulation of occludin expression in the patients with melanoma is a hallmark of cancer progression and it might be used as a prognostic factor. No significant correlation was found between occludin gene expression and clinicopathological characteristics including Clark level, Breslow staging, mitotic count, age and gender (P<0.05).


Main Subjects




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