Expression and significance of FOXO3a and MMP 9 in colorectal cancer / 重庆医学

Objective To investigate the expression of FOXO3a and MMP 9 in colorectal cancer tissues and their relationship . Methods Tissue microarray and immunohistochemical SP methods were used to detect the expression of FOXO 3a and MMP 9 in 78 cases of colorectal cancer tissues and 69 cases of corresponding normal intestinal mucosa tissues ,then analyze the relation be-tween their expression and the clinicopathologic parameters of the patients ,and the relation between the expression of FOXO3a and MMP 9 .Results (1)The positive expression rate of FOXO3a in 78 cases of colorectal cancer tissues and 69 cases of normal intesti-nal mucosa tissues are 57 .69% (45/78)and 95 .65% (66/69) ,the positive expression rate of MMP 9 in 78 cases of colorectal cancer tissues and 69 cases of normal intestinal mucosa tissues are 85 .90% (67/78) and 15 .94% (11/69) ,and the difference is significant (P=0 .000) .(2)The decreased expression of FOXO3a and the increased expression of MMP 9 in colorectal cancer are significantly correlated with the depth of tumor invasion ,tumor histological differentiation ,metastasis of lymph node and TNM stage (P0 .05) .(3)There was a negative corre-lation between the expression of FOXO3a and MMP 9 (r=0 .272 ,P<0 .05) .Conclusion The decreased expression of FOXO3a and the increased expression of MMP 9 may be closely related with carcinogenesis ,invasion and metastasis of colorectal cancer ,and their combination may be an important indicator to evaluate the malignant degree and prognosis of the colorectal cancer .

Initial screening of binding-peptide of the cell surface marker CD133 of cancer stem cells / 北京大学学报(医学版)

Objective:To select the binding-peptide of the cell surface marker CD133 of cancer stem cells from phage peptide library,and to find a new tool for research on stem cells,tumor therapy and anti-metastasis of cancer.Methods:Biotined mouse CD133 extracellular fraction was used as a target to screen phage 7-peptide library by the high affinity of streptavidin and biotin,and the clones were identified by sandwich ELISA and competitive experiment.Single strand DNA was extracted from these positive clones and was analyzed by single-strand dideoxy-sequencing.Results:After three turn solution panning,five peptides with high affinity shared the same amino acid sequence:APSPMIW and three identical peptides with high affinity shared the same amino acid sequence:LQNAPRS.Conclusion:The peptides that bind with mouse CD133 extracellular fraction with high affinity and specificity were first screened from the phage peptide library for the first time,which initially indicates that the feasibility of screening from phage peptide library with small molecule polypeptide biotined as a target.