CLTCL1 and cancer: To date, several more ALK hybrid proteins have been identified in various cancer types, such as TRK-fused gene (TFG)-ALK, tropomyosin 3 (TPM3)-ALK, tropomyosin 4 (TPM4)-ALK, clathrin heavy chain-like 1 (CLTCL1)-ALK, and moesin (MSN)-ALK [5].