To Investigate The Clinical Application Of GPR35 As A New Tumor Marker In The Diagnosis And Treatment Of Prostate Cancer

Objective: To evaluate the expression of GPR35 in the tissues and serum of prostate cancer patients step by step by using bioinformatics analysis,immunohistochemistry and ELISA,and to explore its application value in the clinical diagnosis and treatment of prostate cancer.Methods: Based on preliminary experiments and literature reports,GPR35 was preliminarily identified as the research object.Bioinformatics was used to compare the expression of GPR35 in prostate cancer and other tumor tissues,and then to analyze the correlation between GPR35 and survival prognosis of prostate cancer patients and other pathological data.Immunohistochemical staining was used to analyze the expression of GPR35 in paraffin sections of different groups(25 cases of prostate cancer,10 cases of matching normal tissue and 20 cases of prostate hyperplasia)and the relevant pathological data.On this basis,59 patients undergoing prostate biopsy were divided into four groups according to pathological diagnosis:prostate cancer group(34 cases),prostate benign disease group(25 cases),and healthy physical examination personnel(34 cases)as control group.Serum samples of each group were collected,and the expression levels of GPR35 were detected by ELISA,PSA and f PSA were detected by chemiluminescence.The serum expression of GPR35 in each group was compared,and the correlation between serum GPR35 expression level and tumor size(maximum diameter),lymph node metastasis,vesical seminal vesiculate gland metastasis,nerve invasion,TNM stage and Gleason score in prostate cancer patients was analyzed.Receiver operating characteristic(ROC)curve analysis was used to evaluate the efficacy of GPR 35 alone and in combination with PSA and f PSA tests in the diagnosis of prostate cancer.Results: Bioinformatics analysis showed that the expression trend of GPR35 was different in different tumors.The expression level of GPR35 in prostate cancer was significantly higher than that in normal tissues(P <0.001),and the overall survival time and prognosis of prostate cancer patients with high GPR35 expression was shorter and worse than that of patients with low expression.GPR35 expression was closely associated with overall survival time(P =0.008),disease-free survival time(P =0.020),especially disease-free progression time(P < 0.001),and GPR35 expression was an independent prognostic factor of prostate cancer.Retrospective immunohistochemical test results showed that the expression level of GPR35 in prostate cancer tissues was significantly higher than that in paracancer tissues(P=0.0004)and hyperplasia tissues(P=0.0022)(P < 0.01).Further ELISA results showed that the serum GPR35 level in prostate cancer patients [1.01(0.72,1.28)ng/ml] was significantly higher than that in benign prostate disease group [0.61(0.36,0.82)ng/ml](P< 0.05)and normal control group [0.57(0.35,0.94)ng/ml](P < 0.05);Serum GPR35 expression level was correlated with malignant invasive behaviors such as lymph node metastasis,vesical seminal vesicle metastasis and nerve invasion in prostate cancer patients(P < 0.05).The AUC of serum GPR35 was 0.780,the sensitivity was 88.24%,and the specificity was 57.63%.The AUC of GPR35 combined with PSA and f PSA in the diagnosis of prostate cancer was 0.927,the sensitivity was 98.31% and the specificity was73.53%.Conclusions: GPR35 has certain value in the clinical diagnosis of prostate cancer.The combined detection of GPR35,PSA and f PSA can improve the clinical diagnostic efficacy of GPR35.Gpr35 may be a new biomarker for prostate cancer diagnosis.