Abstract: Objective To investigate the expressions of Receptor-interacting protein 2（RIP2）in tissues of rectal cancer（RC）and adjacent tissues，and the relationship with the clinicopathologic factors of RC.Methods The clinicopathological data of 77 patients with rectal?cancer who admitted to the Renmin Hospital of Wuhan University from January 2016 to January 2017 were collected.The expressions of RIP2 in cancer and adjacent tissues were detected using immunohistochemical assay.Semi-quantitative data of immunohistochemical assay was analyzed within independent T test.The relationship between the expression of RIP2 and clinicopathologic factors was then analyzed within the chi-square test.Results In these 77 cancer cases，RIP2 is positively expressed in 44 samples，accounted for 57.1%，and 50 cases in adjacent tissues，totally accounted for 64.9%.The difference is not statistically significant（χ2 =0.983，P>0.05）.The positive expression rate of RIP2 in poorly differentiated and undifferentiated cases ，stage Ⅲ and stage Ⅳ cases，cases with lymph node metastasis and cases with vein invasion was higher than that in cases of high and middle differentiation ，stageⅠand stageⅡ，no lymph node metastasis and no vein invasion（P<0.05）.However，the positive expression of RIP2 has nothing with sex，age and tumor size（P>0.05）.Besides，semi-quantitative analysis shows that the expression of RIP1 and RIP3 in rectal cancer is less than normal tissue（t=-4.305，P<0.05）.Conclusion The expression of RIP2 in rectal cancer is up regulated，and may be a potential reference designator to judge the prognosis of patients with rectal cancer.

Key words: Receptor-interacting Protein 2, Rectal Cancer, Immunohistochemical assay