Expression Of MSEPT9 In Colorectal Cancer And Its Correlation With Clinicopathological Features

Objective : To analyze the clinical value of plasma Septin9 gene methylation(mSEPT9)in auxiliary diagnosis,surgica,efficacy,evaluation,recurrence and metastasis monitoring of colorectal cancer,and to further explore the correlation between the positive expression of mSEPT9 and the clinicopathological features of colorectal cancer.Methods:Patients were collected from the Department of Gastrointestinal surgery of Guilin people’s Hospital from January 2021 to February 2022.75 patients with colorectal cancer(CRC)were diagnosed and divided into two groups according to the pathological results of electronic colonoscopy or postoperative pathology.75 patients in the experimental group were diagnosed as the experimental group.The clinicopathological data of the patients in the experimental group were complete and treated by operation.40 healthy people were included in the control group,and the levels of mSEPT9 in peripheral blood of all patients were detected.Peripheral blood samples were collected from patients with CRC 1-2 days before operation and 30 days after operation.The Ct value of Septin9 gene methylation in peripheral blood was measured by real-time fluorescence probe PCR method.The relationship between mSEPT9 and clinicopathological parameters of CRC patients was analyzed.ROC curve was drawn to evaluate the efficacy of peripheral blood mSEPT9,CEA and combined diagnosis in the diagnosis of colorectal cancer.By comparing the results of mSEPT9 detection before and after operation,the potential clinical value of peripheral blood mSEPT9 in the evaluation of surgical efficacy and tumor load of colorectal cancer was evaluated.Patients with colorectal cancer were followed up for one year to observe the relationship between the persistent positive expression of mSEPT9 and CEA before and after operation and the recurrence and metastasis of the patients.Results:The positive expression rate of mSEPT9 and CEA in the experimental group was significantly higher than that in the control group(P <0.05).The positive expression rate of mSEPT9 in the experimental group was correlated with the distant metastasis and tumor diameter of colorectal cancer(P< 0.05).The positive expression rate was not significantly correlated with sex,age,tumor location,tumor differentiation and lymph node metastasis.The low Ct value mSEPT9 positive expression group was significantly correlated with colorectal cancer distant metastasis and lymph node metastasis.Compared with the high Ct value mSEPT9 positive expression group,the patients with low Ct value mSEPT9 positive expression were more likely to have lymph node metastasis and distant metastasis.The sensitivity of single detection of mSEPT9 and CEA in blood for the diagnosis of colorectal cancer was 68% and 50.33%respectively,and the specificity was 90% and 92.5% respectively.The sensitivity and specificity of combined detection of mSEPT9 and CEA in the diagnosis of colorectal cancer were 78% and 90%,respectively,which were significantly higher than the diagnostic efficacy of single detection,and had similar specificity.51 patients with CRC were positive for mSEPT9 in peripheral blood before operation,the positive rate was 68%,and 31 patients turned negative after operation,with a negative rate of about 60.8%.Among the20 patients with persistent positive mSEPT9 before and after operation,13 patients had tumor recurrence(including tumor progression)or metastasis(P <0.01).37 patients with CRC were positive for CEA in peripheral blood before operation,with a positive rate of 50.33%.19 patients turned negative after operation,with a negative rate of 51.4%.Among the 18 patients with persistent positive CEA before and after operation,10 patients with colorectal cancer had tumor recurrence(including tumor progression)or metastasis.Conclusions:The positive expression rate of mSEPT9 in blood of patients with colorectal cancer was significantly increased,which was closely related to the characteristics of clinicopathological parameters of colorectal cancer.Ct value further sublayer analysis had obvious advantages in identifying lymphatic metastasis and distant metastasis of colorectal cancer.As a biomarker of colorectal cancer in blood,mSEPT9 can be used for early diagnosis of colorectal cancer.Combined with CEA,the detection of mSEPT9 can significantly improve the positive rate of colorectal cancer diagnosis.MSEPT9 also shows application value in surgical efficacy,tumor load evaluation,recurrence and metastasis monitoring.