BioCentury
ARTICLE | Preclinical News

TGFB inhibition could treat checkpoint inhibitor-resistant cancer

February 14, 2018 11:14 PM UTC

In two studies published in Nature, scientists uncovered the role of transforming growth factor (TGF) beta in the tumor microenvironment, and suggested that blocking TGF beta could help treat cancers resistant to checkpoint inhibitor therapies.

In the first paper, researchers from the Genentech Inc. unit of Roche (SIX:ROG; OTCQX:RHHBY) evaluated treatment response to PD-L1 inhibitor Tecentriq atezolizumab in patients from the Phase II IMvigor210 trial to treat metastatic urothelial cancer. Non-responders had increased CD8+ T cell expression and fibroblast TGF beta signaling in the peritumoral stroma, which was associated with reduced overall survival (OS). The researchers identified this phenotype as an immune-excluded tumor microenvironment, in which T cells cannot penetrate the tumor but remain in the stroma...