Targeting anaplastic lymphoma kinase in neuroblastoma

Abstract

Over the last decade, anaplastic lymphoma kinase (ALK), a receptor tyrosine kinase (RTK), has been identified as a fusion partner in a diverse variety of translocation events resulting in oncogenic signaling in many different cancer types. In tumors where the full‐length ALK RTK itself is mutated, such as neuroblastoma, the picture regarding the role of ALK as an oncogenic driver is less clear. Neuroblastoma is a complex and heterogeneous tumor that arises from the neural crest derived peripheral nervous system. Although high‐risk neuroblastoma is rare, it often relapses and becomes refractory to treatment. Thus, neuroblastoma accounts for 10–15% of all childhood cancer deaths. Since most cases are in children under the age of 2, understanding the role and regulation of ALK during neural crest development is an important goal in addressing neuroblastoma tumorigenesis. An impressive array of tyrosine kinase inhibitors (TKIs) that act to inhibit ALK have been FDA approved for use in ALK‐driven cancers. ALK TKIs bind differently within the ATP‐binding pocket of the ALK kinase domain and have been associated with different resistance mutations within ALK itself that arise in response to therapeutic use, particularly in ALK‐fusion positive non‐small cell lung cancer (NSCLC). This patient population has highlighted the importance of considering the relevant ALK TKI to be used for a given ALK mutant variant. In this review, we discuss ALK in neuroblastoma, as well as the use of ALK TKIs and other strategies to inhibit tumor growth. Current efforts combining novel approaches and increasing our understanding of the oncogenic role of ALK in neuroblastoma are aimed at improving the efficacy of ALK TKIs as precision medicine options in the clinic.

ALK ligand ALKAL2 potentiates MYCN‐driven neuroblastoma in the absence of ALK mutation

“…Oncogenic ALK was initially described as a nucleophosmin (NPM)‐ALK fusion in anaplastic large cell lymphoma (ALCL) (Morris et al , 1997). Many other ALK fusion proteins have since been described in different cancer forms, such as non‐small‐cell lung cancer, diffuse large B‐cell lymphoma (DLBCL) and inflammatory myofibroblastic tumour (IMT) (Hallberg & Palmer, 2013; Umapathy et al , 2019). Aberrant activation of ALK has also been reported in the childhood cancer neuroblastoma (NB), where both germline and somatic point mutations, predominantly in the kinase domain of the receptor, have been reported (Caren et al , 2008; Chen et al , 2008; George et al , 2008; Janoueix‐Lerosey et al , 2008; Mosse et al , 2008).…”

Pharmacological inhibition of the ALK axis elicits therapeutic potential in Consensus Molecular Subtype 1 colon cancer patients

“…ALK is generally poorly expressed in normal adult tissues, making it a highly promising molecular target for cancer therapy (16). Indeed, ALK is known to be oncogenic in different types of cancer such as Non-Small Cell Lung Cancer (NSCLC) and it has a critical role in neuroblastoma (17), both as a consequence of gene translocation (18), overexpression, point mutations (11,19) or hyper-phosphorylation of the downstream pathways (20). ALK gene copy number gain was also detected in both the alveolar (88%) and embryonal (52%) rhabdomyosarcoma subtypes (21).…”

Repotrectinib (TPX-0005), effectively reduces growth of ALK driven neuroblastoma cells

“…Alterations in the ALK gene are found in both familial and sporadic neuroblastoma cases, and at a higher frequency in the relapsed patient population 6,8,9 . ALK is a receptor tyrosine kinase (RTK) activated by the ALKAL ligands 10–16 . In vertebrates, ALK is expressed in the central and peripheral nervous system 12,14,17 .…”