Expression And Clinical Significance Of RGS2 In Breast Invasive Carcinoma Of No Special Type

ObjectiveG-protein regulating factors 2(RGS2)expression change has involved in the genesis and development of many malignancies.However,the relationship between expression change of RGS2 and breast invasive carcinoma of no special type(BIC-NST)remains obscure.The purpose of this study was to consider the relationship between RGS2 expression and clinical pathological parameters,as well as to find a candidate biomarker that could evaluate the prognosis of patients with breast cancer and is helpful for pathological diagnosis.Methods1.We screened 196 paraffin-embedded samples of BIC-NST from the archives of the Pathology Department at the First Affiliated Hospital of Chongqing Medical University(CQMU)from 2011.Through immunohistochemistry,we observed the expression and the distribution of RGS2 protein in BIC-NST block,and analyzed its relationship with the clinical pathological parameters.2.We screened out 513 data of patients with BIC-NST in TCGA,and analyzed the relationship between the RGS2 m RNA level and the clinical pathological parameters.3.By Gene set enrichment analysis(GSEA),we performed biological function analysis on the 513 data of patients with BIC-NSTResults1.The m RNA expression level of RGS2 in breast cancer tissue was significantly lower than in adjacent normal breast tissue(P<0.001),as was the protein expression level of RGS2(P<0.001).2.The RGS2 protein expression was significantly related with these clinical pathological characteristics negatively including Histological grade(P=0.006),ER status(P=0.003),PR status(P=0.024),Tumor size(P=0.002).3.Age(P=0.006),ER status(P<0.001),PR status(P<0.001),lymph node metastasis(P=0.011),TNM stage(P=0.020)were significantly related to the m RNA expression of RGS2 negatively.4.The low-expression of RGS2 m RNA had a significantly lower overall survival(P=0.002),as did the low-expression of RGS2 protein(P=0.019),and the low-expression of RGS2 was significantly related with the unfavorable survival in BIC-NST independently(protein level,HR=4.602,95%CI=1.467-14.432,P=0.009;m RNA level,HR=2.299,95%CI=1.036-5.099,P=0.041).5.GSEA indicated that the low-expression group of RGS2 contained “VANTVEER BREAST CANCER ESR1 UP”(nominal P value=0.002,false discovery rate q value=0.1435)and “SMID BREAST CANCER LUMINAL B UP”(nominal P value=0.0,false discovery rate q value=0.1295);the over-expression group of RGS2 included “NEGATIVE REGULATION OF CELL PROLIFERATION”(nominal P value=0.0,false discovery rate q value=0.2224)and “NEGATIVE REGULATION OF DEVELOPMENTAL PROCESS”(nominal P value=0.0,false discovery rate q value=0.2326).ConclusionFirst,these results in this study indicated that RGS2 could link with a tumor suppressor gene of BIC-NST,and RGS2 may be a useful biomarker that could evaluate the prognosis of patients with BIC-NST and is helpful for pathological diagnosis.At last,the workflow of this study would be a trend of large-sample retrospective study.