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凝胶阻滞实验证实转染了本实验室构建的hMSH2反义RNA表达质粒的HeLa细胞（HeLa－MSH2-细胞），其细胞抽提物中C·T碱基对和A·C碱基对错配结合蛋白表达明显降低。该细胞系细胞与母本HeLa细胞在生长速率方面无差异，但经十几次传代后，其生长速率加快约两倍，出现了次磺酸磷酸核糖转移酶（hypoxanthinephosphoribosyltransferase,hgprt）自发突变率升高，但不存在N-甲基-N’-硝基-N-亚硝基胍（N－methyl－N’－nitro－N－nitrosogyanidine,MNNG）耐受。认为hMSH2蛋白在错配修复系统中起了错配识别和结合作用，但该基因的突变不能完全解释道传性非息向性结直肠癌（hereditarynonpolpoiscolorectalcarcinoma，HNPCC）病人来源的细胞系的生物学改变。
Gel-blocking experiments confirmed the transfection of HeLa cells (HeLa-MSH2-cells) with the hMSH2 antisense RNA expression plasmid constructed in our laboratory. C•T base pairs and A•C base pairs in cell extracts. Mismatch binding protein expression was significantly reduced. There was no difference in the growth rate between this cell line and parental HeLa cells. However, after more than a dozen passages, the growth rate was about two times faster, and the spontaneous mutation rate of hypoxanthine phosphoribosyltransferase (hgprt) increased. High, but no N-methyl-N’-nitro-N-nitrosogyanidine (MNNG) tolerance. The hMSH2 protein is considered to have mismatched recognition and binding in the mismatch repair system, but the mutation of this gene cannot fully explain the biological changes of cell lines derived from patients with pathological non-responsive colorectal cancer (HNPCC). .