In a murine model of ovarian cancer, fatty acid synthase (FASN) expression in tumor cells correlates with TME lipid content, including both saturated and unsaturated fatty acids as well as triacylglycerols, and TIDC isolated from tumors with high FASN expression exhibit elevated lipid levels and poor T cell stimulating activity when compared to those recovered from tumors in which FASN is silenced. The gene discussed is FASN; the disease is neoplasm.