ABC转运蛋白ABCG2在皮肤黑素瘤中的表达

Expression of ABC Transporter ABCG2 in Malignant Melanoma and lts Significance

目的探讨ABC转运蛋白ABCG2在皮肤黑素瘤中的表达及意义。方法采用免疫组化SP法检测30例黑素瘤、30例皮内痣及5例A375细胞裸鼠移植瘤ABCG2的表达。结果①ABCG2在黑素瘤和皮内痣中的阳性率分别是56.67%和0,两者比较差异有显著性(P<0.05),在A375细胞移植瘤中的是100.00%;②ABCG2在黑素瘤和皮内痣中的阳性细胞率平均值分别是(30.96±56.96)%和0,两者比较差异有显著性(P<0.05),在A375细胞移植瘤中是(10.35±3.99)%;③ABCG2阳性细胞呈团块状或散在分布,阳性细胞胞核大而透亮或小而深染;④黑素瘤ABCG2阳性细胞率与患者性别、年龄及病程的相关性无显著性(P>0.05)。结论ABCG2在黑素瘤中高表达,在皮内痣不表达,在A375细胞系裸鼠移植瘤中高表达。提示黑素瘤对化疗药物的耐药性可能与ABCG2有关,也说明黑素瘤中可能存在肿瘤干细胞。

Objective To investigate the expression of ABC transporter ABCG2 in malignant melanoma and analyze its significance. Methods The expression of ABCG2 in malignant melanoma , intradermal nevus and transplanted tumor of A375 cells in nude mice were immunohistochemically detected by immunohistochemical method. Results ①The positive expression rates of ABCG2 in malignant melanoma and intradermal nevus tissue were 56.67% and 0, respectively. The difference of ABCG2 positive rate between them was of statistically significant （P 〈 0.05 ）. In transplanted tumor of A375 cells in nude mice, the positive rate of ABCG2 was 100.00% ;②The mean of positive cell rates of ABCG2 in malignant melanoma and intradermal nevus were 30.96% ±56.96% and 0, respectively. There was statistically significant difference between the two groups （ P 〈 0.05 ）. In transplanted tumor of A375 cells in nude mice, the mean of positive cell rates were 10.35% ± 3.99% ; ③ABCG2^ ＋ cells distributed in to a lumpy or scatter pattern with large and transparent, or small and darkly stained nucleus ; ④No statistical significance was found between the rate of positive cells in malignant melanoma and sex, age, and the course of disease （ P 〉 0.05 ）. Conclusions There was high expression level of ABCG2 in the malignant melanoma lesions and the transplanted tumor of A375 cells in nude mice, but no expression in intradermal nevus. These results suggested that the expression of ABCG2 in malignant melanoma might relate to the resistance to chemotherapy drugs and there were cancer stem cells in malignant melanoma.