Expression Of VEGF-A And Vasohibin-1 Gene In Gastric Cancer And The Relationship With Clinical Significance

Background&Objective:Tumor growth,invasion and metastasis depend on the formation of new blood vessels,the abundant vascular network in tumor provides nutrients for the growth of tumor and the way of hematogenous metastasis.Therefore,rich microvascular system is one of the characteristics of malignant solid tumors,and is related to its malignant biological behaviors.Angiogenesis depends on the local balance of angiogenesis stimulating factor and angiogenesis inhibitors.Vascular endothelial growth factor(VEGF)and angiogenesis inhibitory protein(Vasohibin-1,VASH-1)participate in a variety of human tumors' occurrence and metastasis as angiogenesis regulatory factors.This study aims to explore the characteristics of VEGF-A and VASH-1 gene expression level in gastric carcinoma,and relationship between the expression level and clinical pathological features of gastric cancer patients.Methods:We chose 52 gastric cancer patients who underwent surgical treatment in Clinical Medical College of Yangzhou University(Jiangsu Subei People's Hospital)from June 2015 to June 2016.Collect tumor tissue and corresponding normal tissue samples(>5cm from the surgical margin)as experimental group and control group.All the patients didn't receive any chemotherapy or radiotherapy before.All cases were confirmed by pathology after the operation.The tumor tissues and normal tissues were divided into two groups and preserved with liquid nitrogen and formaldehyde solution respectively.We milled the tissues into powder with the help of liquid nitrogen and then preserved in ultra-low temperature(-80?).We use Trizol method to extract total RNA from all specimens.Reverse transcription kit was used to reverse total RNA to cDNA.The expression level of VEGF and VASH-1 mRNA were quantitatively detected by qRT-PCR(Quantitative Real time Polymerase Chain Reaction)method,and the three phosphate dehydrogenase gene(GAPDH)was used as an internal reference.The expression levels of VEGF-A and VASH-1 protein were analyzed by immunohistochemical staining.The expression level of VEGF-A and VASH-1 mRNA in gastric cancer patients was compared with their clinicopathological features.Results:qRT-PCR detection results show that the expression of VEGF-A mRNA in gastric cancer tissues and corresponding adjacent tissues is 4.15�1.12?1.14�0.55,the expression of VASH-1 mRNA in gastric cancer tissues and corresponding adjacent tissues is 5.69�1.25?1.09�0.49?The differences both have statistical significance(P<0.05).The negative,positive and strong positive expression rates of VEGF-A protein in gastric cancer tissues are 15.4%(8/52)?44.2%(23/52).40.4(21/52)%by immunohistochemistry,and the negative,positive and strong positive expression rates of VASH-1 protein arel9.2%(10/52)?46.2%(24/52)?34.6%(18/52).The positive expression rate of VEGF-A in gastric carcinoma is 84.6%(44/52),which is significantly higher than that in adjacent tissues 19.2%(10/52),the difference between the two groups is statistically significant(P<0.05).The positive expression rate of VASH-1 in gastric carcinoma is80.8%(42/52),which is significantly higher than that in adjacent tissues 17.3%(9/52),the difference between the two groups is statistically significant(P<0.05).The expression level of VEGF-A in gastric carcinoma is correlated with tumor differentiation,TNM stage and distant metastasis(P<0.05),but not with sex,age and tumor size.The expression level of VASH-1 is correlated with TNM stage and distant metastasis(P<0.05),which is not related to sex,age,tumor size and differentiation.Conclusion:1.The expression of VEGF-A and Vasohibin-1 in both mRNA and protein level in gastric cancer tissues is higher than those in adjacent normal tissues.The expression level of Vasohibin-1 is positively correlated with the expression level of VEGF in gastric cancer tissues.2.VEGF-A and VASH-1 are closely related to the occurrence and development of gastric cancer.3.VEGF-A expression is correlated with tumor differentiation,TNM stage and distant metastasis in gastric cancer patients while Vasohibin-1 expression is correlated with TNM stage and distant metastasis.