siRNAs, CRISPR-Cas9, or SMIs of the Rasal1 pathway could be used in ACT of T cells that express tumor-specific T-cell receptors (TCRs) or chimeric antigen receptors (CARs). Rasal1 and its binding to ZAP-70 and regulation of the p21ras pathway may serve as a target for the development of novel immunoregulatory drugs. The gene discussed is CARS1; the disease is neoplasm.