A Discussion About The Relation Between Interleukin-13 Rα2 And Colorectal Cancer Liver Metastasis,the Mechanism And Clinical Significance

Purpose:Through the immunohistochemistry way, the research described the expression of IL-13R a 2 in liver metastasis from colorectal cancer and clarify the relationship between IL-13R a 2 and MDSCs. Collecting clinical data of all the patients included to discover the prognosis of metastatic colorectal cancer and its relation with IL-13Ra2.Method:Paraffin sections were used from 11 patients with liver metastases,20 patients with brain metastases,17 cases and 20 cases of no metastasis colorectal cancer primary lesion (T4NxM0). Samples were all performed IL-13Ra 2immunohistochemical staining. In 11 cases/of liver metastases, CD11b and CD33 were stained in order to locate MDSCs in the tissue. All metastasis cases were followed up to obtain postoperative survival data.Results:The rate of IL-13 R a 2-positive cases of CRC LM was 90.8% in the research.CRC LM got the highest rate(primary lesions 40%, brain metastasis 65%, other metastasis 52.9%). The differences were statistically significant between the positive rate of IL-13 R a 2 in CRC LM, primary lesions, brain metastasis and other metastasis(P<0.05). In liver metastasis cases, the results showed linear relationship between the expression of IL-13 R a 2 and quantity of MDSCs (r=0.740, P<0.05). When expression of IL-13 R a 2 increased, the quantity of MDSCs also increased. Among 48 patients with distant metastases, mean survival period is (12.57±12.43) months, the longest 25 months, the shortest four months. The median survival time was 12 months. In the 48 patients, there were 32 patients in IL-13R a 2-positive group and another 16 patients in IL-13R a 2-negative group.The differences were statistically significant between the survival curves of the two groups.Conclusion:Through analysis and comparison of expression levels of IL-13Ra 2 in each colorectal cancer metastases and primary lesions, the research confirmed the over-expression of IL-13R a 2 is associated with liver metastases of colorectal cancer in specific, which may be due to elevated liver tissue MDSCs resulting in tumor immune evasion. Patients with elevated IL-13R a 2 has worse prognosis for distant metastasis in colorectal cancer.It may give new preoperative assessment of the disease.