Expressions And Effects Of MMP-7 And E-CADHERIN In Laterally Spreading Tumor

Objective: Kudo advocated the new category'laterally spreading tumor'in 1998, laterally spreading tumors are defined as lesions≥10mm in diameter with a low vertical axis that extend laterally along the luminal wall, and most of them remain as adenoma or early invasive cancer. LST was correlated significantly with human colorectal carcinomas. At present, the mechanism of colorectal carcinogenesis and characteristic morphous are not clear. In this study, we detected the mRNA expressions of MMP-7 and E-cad in the normal colorectal mucosa, colorectal adenoma and LST to analyze their influences on morphous and clinicopathological characterist- ics of LST.Method: Laterally spreading tumors with clear pathological diagnosis from 10 patients were collected. Colorectal adenoma from 15 patients and mucosa of non-carcinoma were obtained from 5 patients. Reverse transcript- tase PCR(RT-PCR) and immunohistochemistry used to detect the mRNA and protein expressions of MMP-7 and E-cad. SPSS16.0 statistic software was used to analyze the correlation of their abnormal expressions to lateral- ly spreading tumor and adenoma.Results:(1)Immunohistochemistry staining: The detected by immunohistoche - mical stain was positive in the cytoplasm and part of cell membrane was positive. On E-cad immunohistochemistry, positive immunoreactivity was present in the membrane between epithelial cells. The expression of MMP-7 between the adenoma group and LST group was significant difference (P=0.033), we didn't find the expression of MMP-7 in normal mucosa group. The expression of E-cad was no significant difference between adenoma and LST group with normal mucosa group(P>0.05), and between adenoma and LST group the expression of E-cad was no significant difference(P>0.05).(2)mRNA expression of MMP-7 and E-cad: RT-PCR analysis showed that the expression of MMP-7 between the adenoma group and LST group was significant difference(P=0.002), we also didn't find the mRNA expre- ssion of MMP-7 in normal mucosa group; the expression of E-cad in LST group was lower than that in adenoma group and normal mucosa group, there was no significant difference(P>0.05). The mRNA expressions of MMP-7 and E-cad had no relationship with sex, age, location and different- iation(P>0.05). We also didn't find the any relationship between MMP-7 and E-cad in LST group(r=0.152, p=0.676).(3)Correlation between the expression of mRNA with that of protein of MMP-7 and E-cad: The expression of MMP-7 mRNA was positively assoc- iated with that of MMP-7 protein(r=0.89, p=0.007); and there was a posi- tive correlation between expression of E-cad mRNA with that of E-cad protein(r=0.87, p=0.008).Conclusions:1. LST and adenoma may exist function defects of MMP-7 and E-cad.2. MMP-7 may be one of the important elements induced carcinogene- sis in LST; E-cad may be one of the elements lead characteristic morphous of LST different from adenoma.3. There was no correlation between the expression levels of MMP-7 and E-cad.4. Mechanism of carcinogenesis in LST may has relationship with the activation of Wnt/β-cat signaling pathway.