Metabolic Reprogramming: A Crucial Contributor to Anticancer Drug Resistance.

Cancer metabolic reprogramming is a fundamental hallmark that enables tumor cells to sustain their malignant behaviors. Beyond its role in supporting growth, invasion, and migration, metabolic rewiring actively contributes to anticancer drug resistance. Cancer cells not only reshape their own metabolism but also engage in aberrant metabolic crosstalk with nonmalignant components within the tumor microenvironment (TME). These metabolic alterations create multiple barriers to the efficacy of drug therapies, including chemotherapy, targeted therapy, and immunotherapy. Despite growing evidence, an integrated understanding of how metabolic reprogramming contributes to the development of drug resistance and how it may be therapeutically targeted to overcome the resistance remains incomplete. This review summarizes recent progresses in tumor-intrinsic and TME-associated metabolic alterations that contribute to drug resistance by sustaining metabolic needs and modulating nonmetabolic processes and explores the upstream regulatory mechanisms driving these changes, focusing particularly on glucose, lipid, and amino acid metabolism. We also discuss the current advances in the integration of small molecule inhibitors targeting cancer metabolism to address drug resistance. By consolidating mechanistic insights and therapeutic opportunities, this review highlights metabolic reprogramming as a promising intervention point to overcome anticancer drug resistance.