The present invention pertains to engineered immune cells, method for their preparation and their use as medicament, particularly for immunotherapy. The engineered immune cells of the present invention are characterized in that at least one gene selected from a gene encoding GCN2 and a gene encoding PRDM1 is inactivated or repressed. Such modified Immune cells are resistant to an arginine and/or tryptophan depleted microenvironment caused by, e.g., tumor cells, which makes the immune cells of the invention particularly suitable for immunotherapy. The invention opens the way to standard and affordable adoptive immunotherapy strategies using immune cells for treating different types of malignancies.