皮肤基底细胞癌T钙黏蛋白的表达及其DNA异常甲基化分析

The expression and aberrant methylation of T-cadherin in cutaneous basal cell carcinoma

目的 检测皮肤基底细胞癌（BCC）中T钙黏蛋白的表达以及异常甲基化。方法 采用免疫组化法和CpG岛甲基化特异性PCR方法。对29例BCC和19例正常人暴光部位皮肤的组织标本进行T钙黏蛋白的表达及甲基化检测。结果 正常皮肤皆表达T钙黏蛋白，29例BCC中8例（27．59％）检测到T钙黏蛋白表达（P〈0．05），9例BCC（31．03％）和19例正常皮肤中的1例（5．26％）检测到T钙黏蛋白启动子区域的异常甲基化（P〈0．05）。结论 T钙黏蛋白表达降低与皮肤基底细胞癌的发病机制相关，T钙黏蛋白启动子区域的异常甲基化与蛋白低表达可能相关。

Objective To detect the expression and aberrant methylation of T-cadherin in cutaneous basal cell carcinoma （ BCC ）. Methods Skin tissues were resected during operation in light-exposed sites from 29 patients with BCC and 19 normal controls. The expression and aberrant methylation of T-cadherin were tested by immunohistochemical staining and methylation-specific polymerase chain reaction （ MSP ）, respectively. Results Immunohistochemical staining showed that T-cadherin was expressed in 8 of 29 （27.59%） BCC specimens, whereas in all （ 100% ） normal controls, and there was a significant difference in T-cadherin positivity rates between the two groups （χ^2 = 24.46, P 〈 0.05 ）. The aberrant methylation of T-cadherin promoter region was detected in 9 BCC （ 37.93% ） and in 1 （ 5.26% ） control specimen with significant difference between them （χ^2 = 4.62, P 〈 0.05 ）. Conclusion The decrease of T-cadherin expression, likely to be relavent to the aberrant methylation of T-cadberin promoter, might contribute to the pathogenesis of BCC.