散发性结直肠癌组织中hMSH2和hMLH1的表达研究

目的]分析散发性结直肠癌中的hMLH1和hMSH2蛋白表达情况。方法]选取经病理学确诊并在术前未接受过放疗或化疗的结直肠癌手术切除标本127例,以及内镜活检无肿瘤患者肠黏膜上皮20例。用免疫组化方法检测hMLH1和hMSH2蛋白表达情况。结果]结直肠癌组织中hMSH2蛋白表达缺失率为65.4%（83/127）,高于对照肠组织（20.0%,4/20）（χ2=14.714,P〈0.001）。结直肠癌组织中hMSH2蛋白缺失率随T分期增加而增加（χ2=8.233,P=0.041）;与N分期有关（χ2=20.235,P〈0.001）,有淋巴结转移者患者中hMSH2蛋白表达缺失率达87.1%（27/31）,高于无淋巴结转移患者（54.2%）（χ2=9.250,P=0.002）。hMLH1蛋白表达缺失率为74.0%,与T分期（χ2=29.115,P〈0.001）、N分期（χ2=9.807,P=0.006）、M分期（χ2=7.363,P=0.007）有关。结论]结直肠癌组织中存在hMLH1和hMLH2蛋白表达缺失,通过免疫组化方法检测,可以简便、准确地发现错配修复基因的突变,可为后期的治疗和预后判断提供参考。

Expression of hMLH1 and hMSH2 in Patients with Sporadic Colorectal Cancer

Purpose I To investigate the expression of human mutL homolog 1 （hMLH1） and human routS homolog 2 （hMSH2） in sporadic colorectal cancer. Methodsl Expression of hMLH1 and hMSH2 in 127 cases with colorectal cancer without radiotherapy or chemotherapy before opera- tion and 20 cases of non-cancer patients endoscopically proved was detected immunohistochemically. Results] The loss rate of hMSH2 expression in colorectal cancer tissue was higher than that in control tissue （65.4% vs 20.0% ,X2=14.714,P〈0.001）. The loss rate of hMSH2 expression increased with T staging （χ2=8.233,P=0.041）,and was correlated with N stage （χ2=20.235 ,P〈 0.001 ）. The loss rate of hMSH2 expression in patients with lymph node metastases was 87.1% （27/31） ,higher than that in patients without lymph node metastases （54.2%） （χ2=9.250 ,P=0.002）. The loss rate of hMLH1 expression in eolorectal cancer tissue was 74.0%, and was correlated with T stage （χ2=29.115, P〈0.001 ）, N stage （χ2=9.807, P=0.006）, M stage （χ2=7.363, P=0.007 ）. Conclusion]There is loss expression of HMLH1 and hMSH2 in colorectal cancer, and immunohistochemistry can find mutation of mismatch repair genes easily and accurately,which can provide a refer- ence for late treatment and prognostic evaluation.