ALK and cancer: Prominent examples of oncogenic RTK/RAS/MAPK signaling in cancer include naturally occurring chromosomal rearrangements involving RTKs such as anaplastic lymphoma kinase (ALK) or rearranged during transfection (RET), which generate chimeric (fusion) oncoproteins that are validated therapeutic targets across multiple cancer subtypes (Childress et al., 2018; Kato et al., 2017).