TGFβ pathway inhibition in the treatment of non-small cell lung cancer

Advanced non-small cell lung cancer (NSCLC) continues to be an incurable family of thoracic malignancies that is chronically managed with chemotherapy, targeted therapy, and immunotherapy. While the discovery of driver oncogenes and the advent of targeted and immunotherapies in the last decade have vastly improved clinical disease management for patients harboring druggable mutations, the mainstay treatment for the majority of NSCLC patients remains cytotoxic chemotherapy. The clinical efficacy of targeted, immune, and cytotoxic therapies is limited by the development of drug resistance. Transforming growth factor beta (TGFβ) signaling, a crucial mediator of embryonic development and peripheral immune tolerance, may be dysregulated in some malignant contexts, including lung cancer, and has been correlated with poor prognosis in advanced cancers. Aberrant upregulation of TGFβ expression in the tumor microenvironment has also been implicated in promoting NSCLC progression and metastasis, as well as driving the development of resistance to cytotoxic, targeted, and immunomodulatory therapeutic interventions. Here, we examine the mechanisms underlying TGFβ-mediated drug resistance in NSCLC, and consider TGFβ as a combinatorial therapeutic intervention to circumvent or delay the development of NSCLC treatment resistance.