PGR,also named as NR3C3 and PR,belongs to the nuclear hormone receptor family and NR3 subfamily. The steroid hormones and their receptors are involved in the regulation of eukaryotic gene expression and affect cellular proliferation and differentiation in target tissues. Progesterone receptor isoform B (PRB) is involved activation of c-SRC/MAPK signaling on hormone stimulation. The ER and PR status has been used as a predictor of breast carcinoma responsiveness to endocrine therapy and as a prognostic indicator for early recurrence.