Expression Of SOX9 And GKN1 In Gastric Cancer And Its Clinical Significance

Objective:Gastric cancer is the fifth most common malignancy in the world,accounting for 6.8%of the total number of cancers worldwide,and half of them occur in Eastern Asia,especially in China.Surgical resection or adjuvant chemoradiotherapy is preferred for the treatment of gastric cancer,but most patients have been diagnosed with advanced gastric cancer at the time of presentation,and recurrence or metastasis after surgery is not uncommon.The occurrence and development of gastric cancer is related to the complex effects of various oncogenes,tumor suppressor genes and cytokines.With the development of molecular biology research techniques,more and more molecular markers related to gastric cancer have been discovered,and some have been used for clinical diagnosis and treatment.This study was to explore the expression of SOX9 and GKN1 in gastric cancer tissues and its relationship with clinicopathologic features.Methods:Immunohistochemistry was used to detect the expression of SOX9 and GKN1in 70 cases of gastric cancer tissues and corresponding paracancerous tissues including27 cases of intestinal metaplasia and 43 cases of normal gastric mucosa.The relationship of SOX9 and GKN1 expression with clinicopathological features was analyzed in gastric cancer tissues.Results:1.Immunohistochemistry results showed that the staining of SOX9 localized in the nucleus and cytoplasm.The high expression rates of SOX9 in gastric cancer tissues,intestinal metaplasia and normal gastric mucosa were 92.9%(65/70),77.8%(21/27)and55.8%(24/43),respectively,the difference was statistically significant(P<0.05).Compared with normal gastric mucosa,SOX9 expression was up-regulated in gastric cancer(P<0.001).2.In 70 cases of gastric cancer,27 cases of intestinal metaplasia and43 cases of normal gastric mucosa,the high expression rates of SOX9 protein in cytoplasm were 68.6%(48/70),59.3%(16/27)and 51.2%(22/43),respectively,the difference was not statistically significant(?~2=3.474,P=0.176).However,the high nuclear expression rate of SOX9 in gastric cancer tissues was significantly higher than that in intestinal metaplasia[67.1%(47/70)vs.37.0%(10/27),P=0.007]and normal gastric mucosa[67.1%(47/70)vs.23.3%(10/43),P<0.001].3.The high cytoplasmic expression rate of GKN1 in normal gastric mucosa was significantly higher than that in intestinal metaplasia[76.7%(33/43)vs.44.4%(12/27),P=0.006]and gastric cancer tissues[76.7%(33/43)vs.37.1%(26/70),P<0.001].4.Univariate analysis demonstrated that the nuclear expression of SOX9 in gastric cancer was associated with the degree of tissue differentiation(P=0.007),while the cytoplasmic expression of GKN1was associated with the degree of tissue differentiation(P=0.002)and whether the pathological type is signet-ring cell carcinoma(P=0.009).5.Furthermore,the nuclear expression of SOX9 was negatively correlated with the expression of GKN1 in gastric cancer(?~2=15.424,?=0.469,P<0.001).Conclusions:1.The expression of SOX9 is increased in gastric cancer tissues,and its expression level in the nucleus is related to the degree of tissue differentiation.2.The expression of GKN1 in gastric cancer tissues is decreased,and its expression level was related to the degree of tissue differentiation and whether the pathological type is signet-ring cell carcinoma.3.The nuclear expression of SOX9 was negatively correlated with the expression of GKN1 in gastric cancer.4.Changes in the expression of SOX9and GKN1 may be associated with the malignant biological behavior of gastric cancer.5.The combined detection of SOX9 and GKN1 expression and the further study of their molecular mechanism may provide new ideas for early diagnosis,targeted therapy and prognosis evaluation of gastric cancer.