Differential Analysis Of Microsatellite Instability Protein(MSI) Expression In Left And Right Hemispheres

Objective:Through retrospective study to collect the records of 207 patients with colon cancer in recent 3 years,the study of microsatellite instability(MSI)and its four proteins in age,gender,pathological type and degree of differentiation,TNM staging,such as differences,and analyze the possible related factors that affect the survival in patients with colon cancer,for the left and right half colon cancer diagnosis,provides the theory basis for individualized treatment and prognosis.Methods:Retrospective analysis was conducted on clinical data of 207 cases of colon cancer patients(excluding those who had not received surgical treatment)treated by gastrointestinal surgery department of the second affiliated hospital of DaLian medical university in recent 3 years,including 105 cases of left hemicolon cancer patients and 102 cases of right hemicolon cancer patients.The data of case data were established by using Microsoft Excel 97-2003 worksheet,and the data of age,gender,clinical symptoms,pathological type,differentiation degree and TNM stage were collected by referring to the patient s medical records.The data were collected and classified for analysis.The enrolled patients were divided into groups,and the inter-group data were statistically analyzed.The chi-square test was used for the composition ratio,and the log-rank analysis was used to compare the expression differences.Results:1.The median age of enrolled patients in the study was 66 years old,and the distribution between different age groups was also roughly different.However,the peak age of colon cancer was between 50 and 70 years old,and the proportion of patients older than 60 years old was higher in about half of colon cancer patients,and the difference between groups was statistically significant(P=0.042<0.05).2.Patients with a history of smoking and drinking accounted for a higher proportion in left and right colon cancer,but there was no significant correlation between smoking and left and right colon cancer(P=0.096>0.05),while the difference between right and left colon cancer groups was statistically significant(P=0.025<0.05).There was no statistically significant difference between the left and right hemicolon groups in patients with a history of hypertension and diabetes(P>0.05).3.Among the 207 patients with colon cancer,105 cases were found in the left half colon group,102 cases in the right half colon group,a total of 121 cases in males and 86 cases in females.Male patients were mostly found in the left half colon group,while female patients were mostly found in the right half colon group,and the difference was statistically significant(P=0.032<0.05).4.Among the 207 patients with colon cancer,the differentiation degree of each group was in the majority,and there was no statistically significant difference in the differentiation degree and infiltration depth of left and right semi-colon cancer.5.In terms of staging and grading,stage ? and ? are the major proportions of left and right semi-colon cancer,and there is no significant statistical difference.In terms of metastasis,there was no significant difference in lymph node metastasis,distant metastasis,vascular thrombi and nerve invasion between left and right colon cancer.6.In terms of mismatch repair protein,MLH1 and PMS2 showed statistically significant difference in left and right colon cancer(P<0.05),while MSH2 and MSH6 showed no statistically significant difference in left and right colon cancer(P>0.05).The missing expression rates of the four proteins in 105 cases of left hemicolon were as follows:the missing rate of MLH1 was 7/105,the missing rate of MSH2 was 3/105,the missing rate of MSH6 was 3/105,and the missing rate of PMS2 was 13/105.Among them,the common missing rate of MLH1/PMS2 expression was 5/105,and the common missing rate of MSH2/MSH6 expression was 3/105.The missing expression rates of the four proteins in 102 cases of right hemicolon were successively as follows:the missing rate of MLH1 was 17/102,the missing rate of MSH2 was 4/102,the missing rate of MSH6 was 2/102,and the missing rate of PMS2 was 26/102,among which the common missing rate of MLH1/PMS2 expression was 10/102,and the common missing rate of MSH2/MSH6 expression was 2/102.7.In MSI status,and age,high blood pressure,tumor location,histological type and distant metastasis between the difference was statistically significant(p<0.05),MSI-h state of microsatellite instability(high frequency)mainly in the right colon group,and in the age>60 years old,suffering from hypertension,histopathological type of mucus and in patients with distant metastasis,and most of them are concentrated expression for MSI-1 microsatellite instability(low frequency)or MSS(microsatellite stability).Conclusions:1.There were significant differences in the absence of mismatched repair proteins in the left and right hemispheres of colon cancer,and MSI detection was helpful to determine the degree of tumor malignancy and prognosis.2.MSI can provide theoretical basis for individualized treatment and molecular targeted treatment of left and right colon cancer.