| Objective: The prognosis of intrahepatic cholangiocarcinoma is very poor,many patients have lost the opportunity of surgery at the time of presentation,the radical resection rate is low,and the median survival time of patients without surgery is only10-12 months.Even after radical hepatectomy,the survival rate of patients with intrahepatic cholangiocarcinoma is only about 30% after surgery,and the recurrence rate is as high as 60%-70% 3 years after surgery.In addition to surgery,intrahepatic cholangiocarcinoma lacks effective treatment methods and has poor sensitivity to traditional chemoradiotherapy.In recent years,with the discovery of new signaling pathways and therapeutic targets,the clinical application of targeted drugs and immune checkpoint inhibitors,the survival prognosis of a variety of tumors has improved,but the prognosis of intrahepatic cholangiocarcinoma has not improved.Therefore,in order to improve the early diagnosis,treatment and prognosis assessment of intrahepatic cholangiocarcinoma,it is necessary to find new targets.Ras GTPase activator negatively regulates the Ras signaling pathway and is associated with a variety of tumors,and Ras-activating factor analog 3(Rasal3)is a new member of the Ras GTPase family.This study on the expression of Ras activator analogue 3(Rasal3)in intrahepatic cholangiocarcinoma aims to provide a theoretical basis for the discovery of a new target gene for intrahepatic cholangiocarcinoma.Methods: 1.Analyze the m RNA expression data of tissue samples from 36 patients with intrahepatic cholangiocarcinoma and 9 normal patients with GTEx(V8 version)in the Cancer Genome Atlas(TCGA)database,and compare the differential expression of Rasal3 gene between the two groups.The Kaplan-Meier curve analyzed the correlation between Rasal3 expression and survival in patients with intrahepatic cholangiocarcinoma.2.This study retrospectively collected 71 intrahepatic cholangiocarcinoma paraffin samples and paranormal bile duct tissue samples from intrahepatic cholangiocarcinoma who underwent radical hepatic resection in the Department of Hepatobiliary Surgery of The Second Affiliated Hospital of Anhui Medical University from January 2015 to December 2020.General data of patients were collected: age,sex and tumor clinicopathological features: tumor size,TNM stage,degree of differentiation,lymph node metastasis.Immunohistochemical staining was used to detect the expression of Rasal3 protein in intrahepatic cholangiocarcinoma specimens and adjacent normal bile duct tissue samples.3.Collect 21 fresh cholangiocarcinoma tissue samples from our hospital,and use RT-PCR and Western blot methods to further verify the expression of Rasal3 gene and protein in intrahepatic cholangiocarcinoma cells.Result: 1.Database analysis found that Rasal3 was expressed in both intrahepatic cholangiocarcinoma tissue and paracancerous tissue,and the expression in intrahepatic cholangiocarcinoma tissue was higher than in normal paracancerous tissue,and the difference was statistically significant(P<0.05).Patients with intrahepatic cholangiocarcinoma in the Rasal3 group with high expression had a worse overall survival time than those in the normal group.2.Immunohistochemical results showed that Rasal3 was expressed in both intrahepatic cholangiocarcinoma tissue and paracancerous tissue,and the expression in intrahepatic cholangiocarcinoma tissue was significantly higher than in normal paracancerous tissue,and the difference was statistically significant(P <0.05)。 In intrahepatic cholangiocarcinoma tissues,the expression of Rasal3 protein was associated with tumor diameter(χ2=6.983,P=0.008),regional lymph node metastasis(χ2=8.812,P=0.002),TNM stage(χ2=7.895,P=0.005)and tumor differentiation(χ2=2.923,P=0.003).There was no correlation with age,sex,or BMI(P>0.05).3.RT-PCR and Western blot methods further verified the high expression of Rasal3 gene and protein in intrahepatic cholangiocarcinoma tissues relative to normal bile duct tissues adjacent to cancer. |
