Expression And Clinical Significance Of YAP Protein In Colorectal Cancer Tissues

Objective: To envaluate YAP protein in normal colorectal mucosa tissues,hyperplastic polyps,adenomatous polyps and colorectal cancer tissues,and the relationship of the expression of the YAP protein in development of colorectal adenocarcinoma mucosa.Methods: All colorectal tissue sample gathered from the endoscopy room,The affiliated hospital of Qingdao university.15 cases of normal colorectal mucosa tissues,25 cases of hyperplastic polyps,40 cases of adenomatous polyps,40 cases of adenocarcinoma tissues,all of the patients diagnosed as adenocarcinoma had been proved by surgery and postoperative pathology,the pathological results were consistent with the pathological diagnosis of endoscopy.Using the immunohistochemical En Vision method to detect the positive expression of YAP in different colorectal tissues,the semi-quantitative integral method was used in grading.That is,according to the percentage of positive cells and the staining intensity score,and five high-power views were randomly selected for observation.According to the differentiation degree of colorectal cancer,the expression of YAP was further analyzed in high differentiation,middle differentiation and low differentiation group.It also explore that pathological relation of YAP expression among colorectal cancer differentiations.Results: In normal colorectal mucosal tissues,YAP has low expression or no expression(6.7%).The positive expression rates in the tissues of colorectal hyperplastic polyps,adenomatous polyps and adenocarcinoma are 16.0%?35.0%?62.5%,and the difference is statistically significant(P < 0.01).The expression rate of YAP in low differentiated adenocarcinoma was(83.3%)higher than in high(40.0%)or middle(50.0%)differentiation(P<0.05).The positive expression of YAP was not significantly different from the age,gender,tumor location and tumor size of the patients(P>0.05).The positive expression rate of stage III and IV YAP protein was 84.2%,higher than 52.4% in stage I and II,(P < 0.05),which was significant for the clinical stages of tumor patients.It was found that YAP in colon adenocarcinoma with lymph node metastasis was 86.9%,significantly high than 41.2 % of the lymph node free metastases(P<0.05).Conclusion: The Hippo-YAP signal pathway might involve in the development of colorectal cancer,and the YAP protein did not expressed or under expressed in the normal colorectal membrane.But Increasingly expressed in benign tissues include proliferative polyps,adenomatous polyps and malignant adenocarcinoma,and more apparent positive expression in malignant tissues,YAP protein may be used as a tumor marker for early screening of colorectal cancer.The high expression of YAP protein might be related to the level of differentiation of colorectal adenocarcinoma.The lower the differentiation degree,the higher the positive expression rate of YAP protein,and the prognosis of patients could be predicted by the level of YAP expression level.YAP expression level is associated with clinical stages,lymph node metastasis of colorectal cancer,and to participate in the local invasion and distant metastasis of the tumor.There might be a valuable clinical indicator in the research and development of targeted anti-tumor drugs and the mechanism of tumor resistance.