Downregulation of regulator of G protein signaling 2 expression in breast invasive carcinoma of no special type: Clinicopathological associations and prognostic relevance

Changes in the expression of regulator of G protein signaling 2 (RGS2) are involved in the genesis and development of a number of malignancies. However, the association between changes in the expression of RGS2 and breast invasive carcinoma of no special type (BIC-NST) remains unknown. The present study found that, in comparison to normal breast tissue, BIC-NST exhibited low expression of RGS2 mRNA and protein, as detected using data mining and immunohistochemical analysis. The low expression of RGS2 was associated with the positive status of hormone receptor expression in BIC-NST. Kaplan-Meier analysis revealed that patients with low RGS2 expression had a significantly poorer overall survival rate. Furthermore, multivariate Cox regression analysis demonstrated that the RGS2 low expression was an independent high-risk factor. Gene set enrichment analysis using data from The Cancer Genome Atlas supported these results. In summary, the results of the current study indicate that RGS2 acts as a suppressor gene in the progression of BIC-NST. To the best of our knowledge, the present study is the first concerning the association between RGS2 and hormone receptors in BIC-NST, as well as that between RGS2 expression and the prognosis of patients with BIC-NST. However, the effect of RGS2 in breast cancer requires further investigation.