5-羟甲基胞嘧啶表达与黑素瘤侵袭、转移、预后的相关性分析

Abstract

Objective To detect the level of 5-hydroxymethyl-cytosine (5-hmc) in melanoma tissues, and to analyze the correlation between 5-hmc and the invasion, metastasis and prognosis of melanoma. Methods A streptavidin-peroxidase immunohistochemical method was used to detect the level of 5-hmc in 67 melanoma tissues and 20 pigmented nevi tissues. Univariate and multivariate analyses were performed with the Cox′s proportional hazards regression model to analyze the correlation between the expression of 5-hmc and the prognosis of melanoma. Results The expression rate of 5-hmc was significantly lower in melanoma tissues than in pigmented nevus tissues (40.30%[27/67] vs. 75%[15/20], χ2 = 7.428, P = 0.006) . According to American Joint Committee on Cancer (AJCC) TNM staging system, the expression level of 5-hmc was significantly lower in the stage Ⅳmelanoma tissues than in the stage Ⅱ and stage Ⅲ melanoma tissues (χ2 = 4.416, P = 0.036) . Patients with lymph node metastasis showed significantly lower expression of 5-hmc compared with those without lymph node metastasis (χ2 = 5.902, P = 0.015) , and the level of 5-hmc expression significantly decreased along with the increase of Clark grade (χ2 = 4.828, P = 0.028) . There were no significant differences in the level of 5-hmc expression between patients of different ages, genders or nationalities (P > 0.05) . Multivariate Cox regression analysis showed that distant lymph node metastasis (HR: 2.67, 95% CI: 1.22-5.84) , not receiving surgical resection (HR: 0.41, 95% CI: 0.18-0.95) , and low expression of 5-hmc (HR: 3.54, 95% CI: 1.09-11.43) were independent risk factors for poor prognosis of melanoma. Conclusion 5-Hmc may participate in the invasion and metastasis of melanoma, and be associated with the prognosis of melanoma. Key words: 5-Methylcytosine; Nevi and melanomas; Biological marker; Prognosis; Neoplasm metastasis