Expression Of Lgr5 Protein In Advanced Rectal Cancer Tissue Before And After Neoadjuvant Chemotherapy And Its Significance

Objective:To observe the expression changes of Lgr5(Leucine rich repeat-containing G protein coupled receptor 5)in local middle and advanced rectal cancer before and after neoadjuvant radiotherapy and chemotherapy,and to explore its The predictive effect of neoadjuvant chemoradiation.Methods: Eighty-seven patients with stage II and III rectal cancer were enrolled.Firstly,colon cancer biopsy was performed to obtain cancer tissue,then neoadjuvant chemoradiation followed by surgery and tumor tissue was taken;immunohistochemistry was used to detect colonoscopy.Lgr5 protein in biopsy tissue and tumor tissue after surgery.Analyze the change of expression level before and after radiotherapy and chemotherapy,and discuss the relationship with clinicopathological features and therapeutic efficacy.Results: The expression rate of Lgr5 protein was 78.16%(68/87)in the colon biopsy before radiotherapy and chemotherapy.The expression rate of the rectal cancer tissue after radiotherapy and chemotherapy was 29.89%(26/87).There was a statistically significant difference(=40.816,P<0.05);the expression level of Lgr5 was not significantly correlated with the nationality,age,sex,and tumor location of the patient(P>0.05),but was related to tumor differentiation and depth of invasion(cT).Lymph node metastasis(cN)and tumor clinical stage(cTNM)were closely related(P<0.05).The expression of Lgr5 in cT3 and cT4 was significantly higher than that in cT2(83.3% vs 36.4%,P=0.002).The expression of Lgr5 in lymph node positive patients was significantly higher than that in lymph node negative patients(90.2% vs 61.1%,P=0.001);the expression of Lgr5 in clinical stage(cTNM)stage III patients was significantly higher than that in stage II patients(88.2% vs63.8%;(P=0.007);Some patients with rectal cancer after radiotherapy and chemotherapy had varying degrees of tumor pathological withdrawal,and the tumor T stage declining rate was 65.5%(57/87),of which pathologic complete response(pCR)was 12.6%(11/87),Tumor TNM reduction rate was 52.9%(47/87 The expression of Lgr5 protein was negatively correlated with the degree of tumor pathological response after radiotherapy and chemotherapy(rS=-0.333,P=0.002).Conclusion: The positive expression of Lgr5 protein in middle and late rectal cancer suggests that it may be related to the progression of rectal cancer.The expression of Lgr5 protein is decreased after neoadjuvant chemoradiation,and its expression is correlated with the degree of tumor pathology after neoadjuvant chemoradiation.Relevant,suggestive may become a reference index for evaluating the efficacy of neoadjuvant chemoradiation.