Dissecting the NRF2-mediated crosstalk between cancer-associated fibroblasts (CAFs) and NSCLC cells for the development of targeted therapies.

Non-Small Cell Lung Cancer remains one of the most challenging malignancies to treat, characterized by high mortality rates and a complex landscape of therapeutic resistance. While research has traditionally focused on the genetic landscape of tumor cells, the Tumor Microenvironment has increasingly been recognized as a primary driver of malignancy. Among the various cellular components of the TME, Cancer-Associated Fibroblasts (CAFs) play a predominant role, orchestrating a persistent desmoplastic reaction that not only provides a physical scaffold for the tumor itself but also acts as a dynamic signalling hub that promotes progression and resistance to drug. In the context of NSCLC, this aberrant fibrotic response does not merely alter the tissue architecture; it creates a hostile and high-pressure environment that forces both stromal and neoplastic cells to a continuous adaptation, orchestrating the acquisition of new survival strategies in cancer cells. A cornerstone of this adaptation is the ability to withstand oxidative stress and maintain cellular integrity, a process largely governed by the transcription factor NRF2 (Nuclear factor erythroid 2-related factor 2). The regulation of NRF2 is traditionally described through its canonical, KEAP1-dependent degradation pathway. However, in the complex milieu of the lung stroma, NRF2 is often modulated via non-canonical pathways triggered by internal and external factors. TGF-beta which is a master regulator of the fibrotic response, driving the activation of CAFs is a key modulator of non-canonical NRF2 activation. Aalthough the pro-fibrotic effects of TGF-beta are well-documented, the molecular mechanisms underlying the crosstalk between CAFs-derived TGF-beta and the NRF2 antioxidant response in the NSCLC TME remains poorly understood. The overarching goal of this study was to elucidate the molecular mechanisms by which the TME promotes cancer progression and treatment resistance in a preclinical model of human NSCLC, with a specific focus on the interplay between fibrotic signalling and redox homeostasis. By transitioning from simplified cytokine-based models to complex 3D co-culture, the present research aimed to validate the TGF-beta/NRF2 axis as a key mediator of stromal-tumor crosstalk.