Lu et al. demonstrated that tumor-derived factors induce trogocytosis by altering the lipid profile of cytotoxic T-cells, including the depletion of 25-hydroxycholesterol (25HC) by inducing the ATF3 transcription factor to suppress the expression of the 25HC-regulating gene cholesterol 25-hydroxylase (CH25H). The gene discussed is ATF3; the disease is neoplasm.