Methionine restriction sensitizes cancer cells to immunotherapy

Altered metabolism is a defining characteristic of human cancer and holds significant diagnostic value in the clinic.A widely utilized diagnostic tool is the[18F]deoxyglucosepositron emission tomography(FDG-PET)scan,which is based on the fact that cancer cells prefer to uptake glucose,a phenomenon known as the Warburg effect.In addition to the notable shifts in glucose metabolism,cancer cells exhibit distinct alterations in amino acid metabolism.Clinical studies have shown that PET imaging with[11C]-methionine(Met-PET)provides stronger signals and higher specificity in tumor detection compared to the FDG-PET scan[1].The dependence of cancer cells on exogenous methionine is referred to as the Hoffman effect[2],underscoring methionine addiction as a fundamental and general hallmark of cancer.