The present invention relates to a method to engineer immune cell for immunotherapy. In particular said immune cells are engineered with chimeric antigen receptors, which be activated by the combination of hypoxia and ligand extracellular binding as input signals. The invention also relates to new designed chimeric antigen receptors which are able to redirect immune cell specificity and reactivity toward a selected target exploiting the ligand-binding domain properties and the hypoxia condition. The present invention also relates to cells obtained by the present method, in particular T-cells, comprising said chimeric antigen receptors for use in cancer treatments.