Septin9 Gene Methylation Status And Clinical Significance In The Patients With Gastric Cancer

Objective To explore the methylation status of Septin9 gene in the peripheral blood of patients with gastric cancer and the expression of Septin9 gene in gastric cancer tissue and its clinical significance.Methods Collected blood samples of 87 patients with gastric cancer(gastric cancer group)and 55 healthy people(healthy group),and send their specimens to the laboratory of our hospital.Fluorescent probe PCR method is used to detect the methylation status of Septin9 gene in the peripheral blood of the two groups.Calculating the Septin9 gene methylation positive rate,and comparing with other tumor markers.Among 87 cases of gastric cancer,48 cases underwent surgery.The relationship between the methylation status of Septin9 gene in the blood of gastric cancer patients and clinicopathological characteristics was analyzed.Collected surgical specimens from 31 patients with gastric cancer.Immunohistochemical method was used to detect the expression of Septin9 protein,and analyze the expression of Septin9 protein in gastric cancer tissues and clinicopathological correlation of pathological features.Results The positive rate of blood m SEPT9 in the gastric cancer group and healthy group respectively was 60.9%(53/87)and 1.8%(1/55).These two groups have significant statistical significance.The sensitivity of m SEPT9 in peripheral blood of patients with gastric cancer is 60.9%(53/87),and the specificity is 98.2%(54/55).In a single test,the positive rates of CEA,CA199,PGⅠ,m SEPT9 and PGⅠ/PGⅡ in peripheral blood were compared,and the positive rates of PGⅠ and m SEPT9 were the highest.In combined test,the positive rates of CEA+m SEPT9,CA199+m SEPT9,PGⅠ+m SEPT9,and PGⅠ/PGⅡ+m SEPT9 were compared,and there was no statistical difference.Among 87 patients with gastric cancer,the positive rate of m SEPT9 in blood of different ages and genders was no statistically significant(P>0.05).In48 patients with gastric cancer who underwent surgical treatment,there was no statistically significant comparison of m SEPT9 positive rates in the blood of different tumor diameters and clinicopathological stages(P>0.05).The postoperative pathological Lauren classification of intestinal type,diffuse type,and mixed type grouped positive rates are not all the same.Intestinal gastric cancer has a higher positive rate of m SEPT9 in the blood of patients compare to diffuse gastric cancer.The positive rate of Septin9 protein expression in gastric cancer tissues and normal tissues adjacent to cancer respectively was 71.0%(22/31)and25.8%(8/31).The expression rate of Septin9 protein in the two groups was significant statistically different(P<0.01).There was no statistically significant difference in age,gender,tumor diameter,clinical stage and Lauren classification(P>0.05).Conclusion The positive rate of m SEPT9 in the blood of gastric cancer patients is relatively high,which is probobaly to become a tumor marker of gastric cancer.Septin9 gene is highly expressed in gastric cancer tissue,and it may become a new target for the treatment of gastric cancer.