The Clinicopathological And Prognostic Role Of DJ-1 In Pancreatic Neuroendocrine Tumors

ObjectivePancreatic neuroendocrine tumor is a relatively rare heterogeneous tumor originated from pluripotent stem cells.In recent years,the incidence rate has gradually increased,but early diagnosis is difficult.At present,there is no effective serum marker for early diagnosis.As a new multifunctional protein,DJ-1 protein is expressed in many malignant tumors and affects the progression and prognosis of tumors.This study was designed to investigate the expression of DJ-1 protein in serum and pathological specimens of patients with pancreatic neuroendocrine tumors and its relationship with clinicopathological characteristics of pancreatic neuroendocrine tumors.To explore the possible value of DJ-1 protein in the diagnosis and prognosis of pancreatic neuroendocrine tumors.MethodsForty patients with pancreatic neuroendocrine tumors admitted to our hospital from January 2010 to October 2013 were selected as subjects(pancreatic neuroendocrine tumors group).The clinicopathological information of the patients was collected and followed up until December 15,2016.Meanwhile,30 healthy persons in our hospital during the same period were selected as control group.The expression of serum DJ-1 protein was detected by enzyme-linked immunosorbent assay.The difference of serum DJ-1 between pancreatic neuroendocrine tumors group and control group was compared.Detection of DJ-1 protein expression in pancreatic neuroendocrine tumors by immunohistochemical staining.Overall survival of patients was calculated,and analyze the relationship between the expression of DJ-1 protein and the clinicopathological characteristics and the overall survival of patients with pancreatic neuroendocrine tumors.Results1.Compared with healthy people,the expression of serum DJ-1 protein in patients with pancreatic neuroendocrine tumors was significantly higher(p<0.05).2.The positive expression rate of DJ-1 protein was 57.5%(23/40)in pancreatic neuroendocrine tumors.Patients with pancreatic neuroendocrine tumors were divided into DJ-1(+)group and DJ-1(-)group according to the expression of DJ-1.Comparison of clinicopathological characteristics and prognosis in two groups of patients with pancreatic neuroendocrine tumors.The expression of DJ-1 protein was not correlated with age,sex,tumor location,tumor size,tumor embolus and tumor differentiation(p>0.05).In DJ-1(+)group,the proportions of G1,G2 and G3 were 13%,43.5%and 43.5%respectively.In DJ-1(-)group,the proportion of Gl,G2 and G3 was 41.2%,52.9%and 5.9%,respectively.There was significant difference between the two groups(p<0.05).In DJ-1(+)group,the proportions of local,regional and distant metastases were 8.7%,56.5%and 34.8%respectively.In DJ-1(-)group,the proportions of local stage,regional stage and distant stage were 64.7%,23.5%and 11.8%,respectively.There was significant difference between the two groups(p<0.05).3.K-M survival analysis showed that the invasion stage,pathological grade andDJ-1 protein expression were correlated with the prognosis of the patients(p<0.05).The 5-year survival rate of DJ-1(+)group was 62%,and that of DJ(-)group was 94%.There was significant difference between the two groups(p<0.05).Further multivariate COX regression analysis showed that DJ-1 protein expression was not an independent risk factor for overall survival.ConclusionsDJ-1 protein was significantly higher in patients with pancreatic neuroendocrine tumors than in healthy subjects.The expression of DJ-1 protein in patients with pancreatic neuroendocrine tumors was correlated with pathological grade and invasion stage.The higher the pathological grade,the higher the expression of DJ-1 protein in patients with metastasis.Therefore,we think that DJ-1 protein may be involved in the process of invasion and metastasis of pancreatic neuroendocrine tumors.