肝细胞肝癌组织及细胞株中PTPeta的表达及意义研究

Expression of PTPeta in human hepatocellular carcinoma tissue and SMMC7721 cells and its significance

目的检测人肝细胞肝癌组织及细胞株SMMC7721中蛋白酪氨酸磷酸酶eta(PTPeta)的表达,观察肿瘤细胞生长密度对其表达的影响。方法采用免疫组化方法检测肝细胞肝癌组织及SMMC7721细胞中PTPeta蛋白的表达;采用RT-PCR法检测不同生长密度(1×103、5×103、1×104、5×104/cm2)SMMC7721细胞中PTPeta的表达变化情况。结果免疫组化检测结果表明肝细胞肝癌组织中PTPeta表达呈阳性,SMMC7721细胞中存在PTPeta表达,且定位于细胞膜;RT-PCR检测结果显示,当细胞密度为1×103、5×103、1×104、5×104/cm2时,PTPeta mRNA的表达量分别为0.425±0.031、0.659±0.041、0.771±0.043、0.885±0.045,PTPeta表达随着肿瘤细胞生长密度的增高而增加,差异具有统计学意义(P<0.05)。结论 PTPeta在肝细胞肝癌组织及细胞中表达,且随肿瘤细胞生长密度增高而表达增加。PTPeta可能通过增加肝癌细胞黏附、维持恶性肿瘤细胞内环境稳定等,在恶性肿瘤细胞增殖及播散转移的过程中起重要作用。

Objective To investigate the expression of protein tyrosine phosphatase eta （PTPeta） in hepatocellular carcinoma tissue and SMMC-7721 cells, and observe the effects of SMMC7721 cell density on PTPeta expression. Methods Immunohistochemistry method was used to detect the protein expression of PTPeta in hepatocellular carcinoma tissues and SMMC- 7721 cells. RT-PCR was employed to detect the mRNA expression of PTPeta in different growth density of SMMC-7721 cells （1 × 103, 5 × 103, 1 × 104, 5 × 104/cm2）. Results Immunohistochemical detection demonstrated that the PTPeta was positively expressed in hepatocellular carcinoma tissue. Immunofluorescence study showed that PTPeta was also expressed in SMMC-7721 cells, and it was mainly localized in cell membrane. RT-PCR study indicated that the degree of expression of PTPeta mRNA was 0.425 ± 0.031, 0.659 ± 0.041, 0.771 ± 0.043 and 0.885 ± 0.045 respectively in cell density of 1× 103, 5 × 103, 1 × 104 and 5 × 104/ cm2. The expression of PTPeta mRNA was increased along with increase of tumor cell density with statistically significant difference （P〈O.05）. Conclusion PTPeta may by expressed in hepatocellular carcinoma tissue and tumor cells, and the expression may be increased by an increase in cell density. PTPeta may play an important role in proliferation and migration of malignant tumor cells by increasing the adhesiveness ofhepatocarcinoma cells and maintaining the homeostasis of malignant tumor cells.