The TGF beta pathway as a therapeutic target in cancer

The TGF beta pathway has recently emerged as a putative therapeutic target against cancer. However, TGF beta has a complex and dual role in cancer. In normal epithelial cells and early tumours, TGF beta acts as a tumour suppressor. In contrast, during tumour progression TGF beta becomes an oncogenic factor inducing proliferation, angiogenesis, invasion and metastasis, as well as suppressing the anti-tumoral immune response. The role of TGF beta in oncogenesis requires the precise understanding of the TGF beta pathway in order to design optimal therapeutic approaches and select the patient population that may benefit from an anti-TGF beta therapy. Here we review the rationale for evaluating TGF beta signalling inhibitors as cancer therapeutics, and the progress made in the preclinical and clinical testing of anti-TGF beta compounds.