Loss of expression of transforming growth factor beta type II receptor correlates with high tumour grade in human breast in-situ and invasive carcinomas

Aims: Loss of transforming growth factor beta type II receptor (TGF beta-RII) expression has been associated with resistance to TGF beta-mediated inhibition of cell proliferation and tumour progression. We investigated whether the expression of TGF beta-RII is related to the progression of human breast cancer and whether there is a correlation between TGF beta-RII expression and phenotypic markers of biological aggressiveness. Methods and results: Immunohistochemical methods were used to detect TGF beta-RII in archival breast samples including benign proliferative lesions, ductal carcinoma in situ (DCIS) and invasive mammary carcinomas (IMC). Neoplastic cells showed reduced expression of TGF beta-RII in comparison to the normal breast tissue and benign lesions. There was a significant inverse correlation between loss of TGF beta-RII expression and tumour grade within both DCIS (P = 0.004) and IMC (P = 0.001) groups. There was an inverse correlation between TGF beta-RII expression and both mitotic count (P = 0.001) and clinical stage (P = 0.004). Oestrogen receptor (P = 0.07) and lymph node status (P = 0.10) were not significantly associated with TGF beta-RII expression. Conclusions: These data indicate that decreased expression of TGF beta-RII may contribute to breast cancer progression and is related to a more aggressive phenotype in both in-situ and invasive carcinomas.