The present invention provides a method of identifying a target for preparing an inhibitory chimeric antigen receptor (iCAR) or a protective chimeric antigen receptor (pCAR) capable of preventing or attenuating undesired activation of an effector immune cell. Also provided are a list of iCAR targets, as well as vectors and transduced effector immune cells comprising the nucleic acid molecule and methods for treatment of cancer comprising administering the transduced effector immune cells are further provided.