Study On The Expression Of Metastases-related Gene CD44 Variants 6 In Human Gastric Cancer

CD44 (Cluster of differentiation) is a widely expressed integral cell membrane glycoprotein, which can be detected on the Surface of Lymphocytes, fibroblast and epithelial cells. It was first tested and identified with monoclonal antibodies by Pulchau in 1980 and was named as Pgp-1, ECM-III or hyaluronic acid receptor by many research after that. It is a kind of cell adhesion molecule, which contributes to cell-cell and cell-matrix specific adhesions.The expression of CD44v6mRNA in peripheral blood and in bone marrow was detected using-RT-PCR; Semi-quantitative technique; The expression of serum soluble CD44v6 and protein CD44v6 were determined with a quantitative-enzyme-linked-immuno-adsorbent assay and Immuno-histo-chemistry methods; and the real-time-quantitative expression of Serum CD44v6mRNA in before operation and after curative operation was performed with a fluorescent quantitative RT-PCR. It is correlation to the clinical-pathological and metastasis character of gastric cancer was examined.Aim:To detect the expression of CD44v6mRNA/CD44v6 protein in peripheral blood (bone marrow)/tissues of gastric carcinoma, Observe their expression style, analysis their correlation to the clinical-pathology of cancer and further penetrate the possibility and method of assessing the invasive ability of gastric cancer through detection of CD44v6 expression.Method:The expression of CD44v6mRNA was detected using Semi-quantitative RT-PCR and real-time-quantitative RT-PCR technique in the peripheralblood of gastric cancer and partly after surgical cancer; and another methods of quantitative-enzyme-linked-immuno-absorbent-assay, and S-P immuno-histo-chemical technique were used to reveal the expression of serum soluble CD44v6 and the CD44v6 protein.Result (Semi-quantitative-RT-PCR):35 out of 38 peripheral blood of gastric cancer with lymph node metastasis had the expression of CD44v6mRNA (92.10%), 4 out of 8 peripheral blood of gastric cancer without lymph-node metastasis had the expression (50%), which had statistic significance. 32 out of 34 peripheral blood of gastric cancer with III-IV stage's had the expression of CD44v6mRNA (94.12%), 7 out of 12 peripheral blood of gastric cancer with I-II stage's had the expression (58.33%), which had statistic significance. According to Lauren's typing method, CD44v6mRNA expression levels in the intestinal and the diffuse type gastric cancer are different significantly, with the former 9/14(64.28%)expressed and the later 30/32(93.75%). (Real-time-RT-PCR): All of the 20 peripheral blood of gastric cancer had the expression of CD44v6mRNA.The expression levels from 4.9×102 copies/ug RNA to 3.2×105 copies/ug RNA, the average levels of peripheral blood is 3.9×104 copies/ug RNA, The expression levels of peripheral blood of gastric cancer which after curative operation from 5.5×100 copies/ug RNA to 7.6×103 copies/ug RNA, the average levels I 2.4×102 copies/ug RNA, which had statistic significance, after curative operation the expression levels was decreased markedly.(Quantitative-enzyme-linked-immuno-absorbent-assay): The serum concentration of soluble CD44v6 of gastric cancer was markedly higher than the controls, and marked higher than the gastric ulcer, a significant decrease in serum soluble CD44v6 concentration after curative operation, but no obvious decrease after palliative operation, there was significant correlation between the serum levels of CD44v6 and histo-pathologic variables, lymph node metastasis, and different stage of tumor, on the other hand, there was no correlation between the sCD44v6 and the size of tumor. (S-Pimmuno-histo-chemical): CD44v6 is expressed in the tissue of gastric cancer. The expressing rates in diffuse type (39/41,95.12%)was markedlyhigher than in intestinal type (16/29,55.17%), there was significant correlation between the CD44v6 protein and the lymph node metastasis, different stage of tumor, there was no correlation between the CD44v6 protein and the tumor size. Conclusion:1...