TGFBR1 and breast carcinoma: Investigation of a total of breast cancer biopsy specimens using immunohistochemical analysis assessing expression levels of TGFB receptors TGFBR1 and TGFBR2 showed that TGFBR1 expression was detected in 273 out of 555 samples (49%), while TGFBR2 expression was observed in 239 out of 474 cases (50%) [19].