Ubiquitination of LAMTOR1 by TRAF4 promoted its binding to Rag GTPases and enhanced mTORC1 activation, K151R knock‐in or TRAF4 knock‐out blocks amino acid‐induced mTORC1 activation and accelerates the development of inflammation‐induced colon cancer. Here, TRAF4 is linked to malignant colon neoplasm.