Cancer remains one of the most complex challenges in modern medicine, with intricate relationships between immune responses and tumor development. This article examines a groundbreaking study by Fesneau, Thevin and colleagues, published in Nature Immunology. This elegant body of work explores the link between chronic inflammation and cancer, particularly focusing on Th17 cells involved in intestinal cancer initiation. Th17 cells, known for their dual roles in immunity, can promote or inhibit tumor growth depending on their environment. This study reveals that a specific subset of Th17 cells, derived from IL-17-producing cells, can transition to a tumorigenic state when TGF-β signaling is impaired. Surprisingly, TGF-β acts as a crucial regulatory factor, maintaining the balance between immune tolerance and tumorigenesis by preventing Th17 cells from becoming tumorigenic. This research highlights the potential for therapeutic interventions targeting TGF-β signaling to prevent cancer initiation in chronic inflammatory conditions. The findings have clinical implications for improving cancer immunotherapies, including immune checkpoint inhibitors and adoptive T cell therapies, by enhancing the efficacy of treatments and mitigating the risk of tumorigenic transformations. Overall, this study provides insights into the mechanisms linking inflammation and cancer, paving the way for innovative strategies to harness the immunity in cancer treatment.