Hedgehog信号通路在皮肤鳞状细胞癌中表达

目的 探讨Hedgehog信号转导通路在皮肤鳞状细胞癌中的激活水平及抑制该信号通路对鳞状细胞癌增殖的影响。方法 免疫组化和原位杂交方法检测鳞状细胞癌皮损及正常皮肤中Hedgehog信号通路靶基因Ptch-1和Gli-1的表达水平和分布。MTT和BrdU掺入的方法，检测Hedgehog信号转导通路特异性抑制剂环巴胺对Tca鳞状细胞癌细胞生长和增殖的影响。结果 在鳞状细胞癌皮损中Ptch-1表达高于正常人皮肤（免疫组化χ2 = 5.656，P < 0.05；原位杂交χ2 = 6.787，P < 0.01），Gli-1表达也高于正常人皮肤（免疫组化χ2 = 6.732，P < 0.01；原位杂交χ2 = 9.600，P < 0.01），阳性颗粒主要分布于鳞状细胞癌细胞胞质中。MTT和BrdU掺入实验均显示环巴胺可以抑制Tca鳞状细胞癌细胞的生长和增殖。结论 鳞状细胞癌皮损中Hedgehog信号转导通路处于激活状态，抑制该通路可能对鳞状细胞癌起到一定的治疗作用。

Expression of hedgehog signaling pathway in squamous cell carcinoma

Objective To investigate the expression of Ptch-1 and Gli-1, hedgehog pathway-related genes in squamous cell carcinoma (SCC), and the effect of cyclopamine, a specific inhibitor of hedgehog signaling pathway, on the proliferation of a SCC cell line Tca. Methods Skin samples were resected from 42 patients with SCC and 10 normal human controls. Immunohistochemistry and in situ hybridization were employed to study the expression and distribution of Ptch-1 and Gli-1 in these specimens. Tca cells were incubated with cyclopamine (1, 2, 5, 10 μmol/mL) for 48 hours, or cyclopamine (5 μmol/mL) for 1-8 days. The same concentrations of lycopersicin served as the control treatment. Then, MTT assay was performed to detect the proliferation of Tca cells. A fraction of Tca cells were cultured in the presence of 5 μmol/mL cyclopamine for 72 hours followed by BrdU assay for the evaluation of cell growth and proliferation. Results A significant increment was shown in the expression of both Patch-1 and Gli-1 by immunohistochemistry (χ2= 5.656, 6.732, P<0.05, 0.01, respectively) and in situ hybridization (χ2=6.787, 9.600, respectively, both P<0.01) in SCC tissue compared with the control specimens. And both of them were predominantly distributed in the cytoplasm of SCC cells. As MTT assay revealed, cyclopamine notably inhibited the proliferation of Tea cells, and the effect increased with the concentration and action time of cyclopamine. Further more, the percentage of BrdU-positive cells was 26% in cyclopamine-treated Tca cells, significantly higher than that in the blank control cells (77%) and lycopersicin-treated cellls (72%). Conclusions Hedgehog signaling pathway is activated in the lesions of SCC, and inhibition of the pathway may facilitate the treatment of SCC.