The role of anaplastic lymphoma kinase in pediatric cancers

Middle-Out Physiologically Based Pharmacokinetic Modeling to Support Pediatric Dosing Recommendation for Alectinib

Adult patients with anaplastic lymphoma kinase positive (ALK+) advanced non-small-cell lung cancer (NSCLC) are treated with 600 mg alectinib twice daily (BID) as first-line treatment. ALK positive solid and central nervous system (CNS) tumors are described in the pediatric population, with limited clinical data due to the rarity of the disease and challenges to determine the right dosing. This study aims to inform pediatric dose recommendations for alectinib by performing a middle-out physiologically based pharmacokinetic (PBPK) modeling approach, accounting for differences in absorption and enzyme maturation. The developed adult PBPK model is leveraging insights from two previously developed PBPK models (focusing on absorption and drug-drug interactions) and is complemented with newly generated data. The adult PBPK model is validated with pharmacokinetic data from two clinical studies in the adult population. The ratios between the predicted and observed steady-state AUC after 600 mg BID for 28 days are within the acceptable range in three different adult body weight categories (from 0.81 to 1.02). Initial pediatric dose recommendations are informed by population PK model predictions (assuming no maturation of enzymes) and aim to have similar exposure to the adult population. Intrinsic clearance values for all contributing CYP enzymes are included in the pediatric PBPK model to account for changes in enzyme maturation. The current PBPK model confirmed that the recommended alectinib doses by population PK predictions were accurate for the pediatric age range, with one exception: patients younger than 3.5 years are suggested to receive 100 mg BID, instead of 190 mg BID.

Molecular mechanism of genetic, epigenetic, and metabolic alteration in lung cancer

Lung cancer, a leading cause of cancer-related deaths worldwide, is primarily linked to smoking, tobacco use, air pollution, and exposure to hazardous chemicals. Genetic alterations, particularly in oncogenes like RAS, EGFR, MYC, BRAF, HER, and P13K, can lead to metabolic changes in cancer cells. These cells often rely on glycolysis for energy production, even in the presence of oxygen, a phenomenon known as aerobic glycolysis. This metabolic shift, along with other alterations, contributes to cancer cell growth and survival. To develop effective therapies, it's crucial to understand the genetic and metabolic changes that drive lung cancer. This review aims to identify specific genes associated with these metabolic alterations and screen phytochemicals for their potential to target these genes. By targeting both genetic and metabolic pathways, we hope to develop innovative therapeutic approaches to combat lung cancer.

Anaplastic Lymphoma Kinase (ALK) in Posterior Cranial Fossa Tumors: A Scoping Review of Diagnostic, Prognostic, and Therapeutic Perspectives

Anaplastic Lymphoma Kinase (ALK) has been implicated in several human cancers. This review aims at mapping the available literature on the involvement of ALK in non-glial tumors localized in the posterior cranial fossa and at identifying diagnostic, prognostic, and therapeutic considerations. Following the PRISMA-ScR guidelines, studies were included if they investigated ALK's role in primary CNS, non-glial tumors located in the posterior cranial fossa. A total of 210 manuscripts were selected for full-text review and 16 finally met the inclusion criteria. The review included 55 cases of primary, intracranial neoplasms with ALK genetic alterations and/or protein expression, located in the posterior fossa, comprising of medulloblastoma, anaplastic large-cell lymphoma, histiocytosis, inflammatory myofibroblastic tumors, and intracranial myxoid mesenchymal tumors. ALK pathology was investigated via immunohistochemistry or genetic analysis. Several studies provided evidence for potential diagnostic and prognostic value for ALK assessment as well as therapeutic efficacy in its targeting. The available findings on ALK in posterior fossa tumors are limited. Nevertheless, previous findings suggest that ALK assessment is of diagnostic and prognostic value in medulloblastoma (WNT-activated). Interestingly, a substantial proportion of ALK-positive/altered CNS histiocytoses thus far identified have been localized in the posterior fossa. The therapeutic potential of ALK inhibition in histiocytosis warrants further investigation.

In Vitro and In Silico Screening of Benzimidazole-Based Ruthenium(II) Complexes as Potent ALK Inhibitor for Cancer Prevention

Two new heteroleptic Ru(II) polypyridyl complexes, [Ru(bpy)2(B)]Cl2 (RBB) (bpy = 2,2'-bipyridine and B = 4,4'-bis(benzimidazolyl)-2,2'-bipyridine) and [Ru(phen)2(B)]Cl2 (RPB), were synthesized, and the structural features were confirmed by the analytical and spectral tools such as FT-IR, 1H-NMR, and UV-Visible spectroscopy. We have explored the possibility of improving the selectivity of cytotoxic Ru(II) complex and their preliminary biological evaluation against MCF-7 and MG-63 cell lines and clinical pathogens. The results of the antimicrobial screening show that the ligand and complexes have a range of abilities against the species of bacteria and fungi that were tested. The anti-inflammatory activity of the compounds was found to be in the range of 30-75%. Molecular docking study was performed for these ligand and complexes to evaluate and analyze the anti-lymphoma cancer activity. Molecular docking score and the rank revealed the bonding affinity towards the site of interaction of the oncoprotein anaplastic lymphoma kinase (ALK).

Identification of the molecular subtypes and construction of risk models in neuroblastoma

The heterogeneity of neuroblastoma directly affects the prognosis of patients. Individualization of patient treatment to improve prognosis is a clinical challenge at this stage and the aim of this study is to characterize different patient populations. To achieve this, immune-related cell cycle genes, identified in the GSE45547 dataset using WGCNA, were used to classify cases from multiple datasets (GSE45547, GSE49710, GSE73517, GES120559, E-MTAB-8248, and TARGET) into subgroups by consensus clustering. ESTIMATES, CIBERSORT and ssGSEA were used to assess the immune status of the patients. And a 7-gene risk model was constructed based on differentially expressed genes between subtypes using randomForestSRC and LASSO. Enrichment analysis was used to demonstrate the biological characteristics between different groups. Key genes were screened using randomForest to construct neural network and validated. Finally, drug sensitivity was assessed in the GSCA and CellMiner databases. We classified the 1811 patients into two subtypes based on immune-related cell cycle genes. The two subtypes (Cluster1 and Cluster2) exhibited distinct clinical features, immune levels, chromosomal instability and prognosis. The same significant differences were demonstrated between the high-risk and low-risk groups. Through our analysis, we identified neuroblastoma subtypes with unique characteristics and established risk models which will improve our understanding of neuroblastoma heterogeneity.

Case report: ALK D1225N missense mutation in lung adenocarcinoma responds to tyrosine kinase inhibitors

ALK gene missense mutations are conventionally considered non-driver mutations without pathological significance, and therefore, there is a lack of effective target drugs against them. The standard treatment option for patients with ALK missense mutations is chemotherapy with or without antiangiogenic agents, which usually results in unsatisfactory outcomes. Herein, we present the case of a patient with metastatic lung adenocarcinoma harboring the only missense mutation in ALK D1225N responding to two ALK-tyrosine kinase inhibitors (TKIs), namely, crizotinib and ensartinib. Our case highlights that non-small cell lung cancer (NSCLC) patients harboring the D1225N mutation may benefit from ALK-TKIs, and therefore, ALK-TKIs should be considered candidates for further line treatment.

ALK Amplification and Rearrangements Are Recurrent Targetable Events in Congenital and Adult Glioblastoma

PURPOSE

Anaplastic lymphoma kinase (ALK) aberrations have been identified in pediatric-type infant gliomas, but their occurrence across age groups, functional effects, and treatment response has not been broadly established.

EXPERIMENTAL DESIGN

We performed a comprehensive analysis of ALK expression and genomic aberrations in both newly generated and retrospective data from 371 glioblastomas (156 adult, 205 infant/pediatric, and 10 congenital) with in vitro and in vivo validation of aberrations.

RESULTS

ALK aberrations at the protein or genomic level were detected in 12% of gliomas (45/371) in a wide age range (0-80 years). Recurrent as well as novel ALK fusions (LRRFIP1-ALK, DCTN1-ALK, PRKD3-ALK) were present in 50% (5/10) of congenital/infant, 1.4% (3/205) of pediatric, and 1.9% (3/156) of adult GBMs. ALK fusions were present as the only candidate driver in congenital/infant GBMs and were sometimes focally amplified. In contrast, adult ALK fusions co-occurred with other oncogenic drivers. No activating ALK mutations were identified in any age group. Novel and recurrent ALK rearrangements promoted STAT3 and ERK1/2 pathways and transformation in vitro and in vivo. ALK-fused GBM cellular and mouse models were responsive to ALK inhibitors, including in patient cells derived from a congenital GBM. Relevant to the treatment of infant gliomas, we showed that ALK protein appears minimally expressed in the forebrain at perinatal stages, and no gross effects on perinatal brain development were seen in pregnant mice treated with the ALK inhibitor ceritinib.

CONCLUSIONS

These findings support use of brain-penetrant ALK inhibitors in clinical trials across infant, pediatric, and adult GBMs. See related commentary by Mack and Bertrand, p. 2567.

Lessons Learned: Utilization of a Reference Laboratory for Targeted Sequencing of Pediatric Tumors at a Single Institution

Our study aims to report the prevalence of potentially actionable oncogenic variants in a sample of pediatric tumors from a single institution using a reference laboratory for tumor profiling. We investigated genomic alterations and immunotherapy biomarkers such a tumor mutation burden, microsatellite instability, and programmed death-ligand 1. Patients treated in the Cook Children's Health Care System who had tumor profiling performed by Foundation Medicine between January 1, 2013, and May 1, 2019, were included. Demographic variables, results of tumor profiling, and subsequent use of targeted therapies were captured. Eighty-one patients were in our final data set; patients had diagnoses of central nervous system tumors (n=5), leukemia and lymphoma (n=4), neuroblastoma (n=32), and other solid tumors (n=40). One or more genomic alterations were identified in 68 (84%) of patients, 34 of which had potential targeted therapies available. In all, 44/51 patients tested for tumor mutation burden had low tumor burden, and the rest had intermediate burden. All 41 patients tested for microsatellite instability status were microsatellite stable. Six of 34 patients tested for programmed death-ligand 1 status were positive. Twelve patients received targeted therapy. This study highlights a subset of pediatric tumors harboring targetable genetic alterations and describes the use of a reference laboratory for tumor profiling.

Drugging Hijacked Kinase Pathways in Pediatric Oncology: Opportunities and Current Scenario

Childhood cancer is considered rare, corresponding to ~3% of all malignant neoplasms in the human population. The World Health Organization (WHO) reports a universal occurrence of more than 15 cases per 100,000 inhabitants around the globe, and despite improvements in diagnosis, treatment and supportive care, one child dies of cancer every 3 min. Consequently, more efficient, selective and affordable therapeutics are still needed in order to improve outcomes and avoid long-term sequelae. Alterations in kinases' functionality is a trademark of cancer and the concept of exploiting them as drug targets has burgeoned in academia and in the pharmaceutical industry of the 21st century. Consequently, an increasing plethora of inhibitors has emerged. In the present study, the expression patterns of a selected group of kinases (including tyrosine receptors, members of the PI3K/AKT/mTOR and MAPK pathways, coordinators of cell cycle progression, and chromosome segregation) and their correlation with clinical outcomes in pediatric solid tumors were accessed through the R2: Genomics Analysis and Visualization Platform and by a thorough search of published literature. To further illustrate the importance of kinase dysregulation in the pathophysiology of pediatric cancer, we analyzed the vulnerability of different cancer cell lines against their inhibition through the Cancer Dependency Map portal, and performed a search for kinase-targeted compounds with approval and clinical applicability through the CanSAR knowledgebase. Finally, we provide a detailed literature review of a considerable set of small molecules that mitigate kinase activity under experimental testing and clinical trials for the treatment of pediatric tumors, while discuss critical challenges that must be overcome before translation into clinical options, including the absence of compounds designed specifically for childhood tumors which often show differential mutational burdens, intrinsic and acquired resistance, lack of selectivity and adverse effects on a growing organism.

Near complete response to ceritinib in a pediatric patient with metastatic ALK-rearranged lung adenocarcinoma

Anaplastic lymphoma kinase (ALK) inhibitors have significant efficacies in ALK-rearranged non-small cell lung cancers (NSCLC). In regard to pediatric NSCLC patients, however, there is a paradox in that on the one hand, they may have a higher probability of ALK-rearrangement positive, but on the other hand, there is no sufficient data for efficacies of ALK inhibitors in pediatric NSCLC patients. Here, we present an 11-year-old boy diagnosed with metastatic ALK-rearranged lung adenocarcinoma. He was treated with ceritinib 450 mg with food once daily and has obtained near complete response in 18th month, with a largely regressed intrathoracic lesion and only localized residual distant metastatic disease. Meanwhile, he showed continued good tolerance after a short period of side effects at the beginning of the dose. This is the first report of the use of ceritinib in pediatric patient with NSCLC.

Case report: ATIC-ALK fusion in infant-type hemispheric glioma and response to lorlatinib

Introduction

Infant type hemispheric gliomas are a rare tumor with unique molecular characteristics. In many cases these harbor mutations in receptor tyrosine kinase pathways and respond to targeted therapy. Here we describe the case of an infant with this type of tumor with a novel ATIC-ALK fusion that has responded dramatically to the ALK inhibitor lorlatinib, despite being refractory to standard chemotherapy.

Case description

The infant was initially treated with standard chemotherapy and found to have an ATIC-ALK fusion. When surveillance imaging revealed progressive disease, the patient was switched to the ALK-inhibitor lorlatinib at 47 mg/m²/day. The patient demonstrated a significant clinical and radiographic response to the ALK inhibitor lorlatinib after just 3 months of treatment and a near complete response by 6 months of therapy.

Conclusion

The ALK inhibitor lorlatinib is an effective targeted therapy in infant type hemispheric glioma patients harboring ATIC-ALK fusion.

Differential expression profiling of onco and tumor-suppressor genes from major-signaling pathways in Wilms' tumor

PURPOSE

Wilms' tumor is the most-frequent malignant-kidney tumor in children under 3-4 years of age and is caused by genetic alterations of oncogenes (OG) and tumor-suppressor genes (TG). Wilms' tumor has been linked to many OG-&-TG. However, only WT1 has a proven role in the development of this embryonic-tumor.

METHODS

The study investigates the level of mRNA expression of 16 OGs and 20 TGs involved in key-signaling pathways, including chromatin modification; RAS; APC; Cell Cycle/Apoptosis; Transcriptional Regulation; PI3K; NOTCH-&-HH; PI3K & RAS of 24-fresh Wilms'-tumor cases by capture-and-reporter probe Code-Sets chemistry, as CNVs in these pathway genes have been reported.

RESULTS

Upon extensively investigating, MEN1, MLL2, MLL3, PBRM1, PRDM1, SMARCB1, SETD2, WT1, PTPN11, KRAS, HRAS, NF1, APC, RB1, FUBP1, BCOR, U2AF1, PIK3CA, PTEN, EBXW7, SMO, ALK, CBL, EP300-and-GATA1 were found to be significantly up-regulated in 58.34, 62.5, 79.17, 91.67, 58, 66.66,54, 58.34, 66.67, 75, 62.5, 62.5, 58, 79.17, 79.17, 75, 70.84, 50, 50, 75, 66.66, 62.50, 61.66, 58.34-and-62.50% of cases respectively, whereas BRAF, NF2, CDH1, BCL2, FGFR3, ERBB2, MET, RET, EGFR-and-GATA2 were significantly down regulated in 58, 87.50, 79.16, 54.16, 79.17, 91.66, 66.66, 58.33, 91.66-and-62.50% of cases, respectively. Interestingly, the WT1 gene was five-fold down regulated in 41.66% of cases only.

CONCLUSION

Hence, extensive profiling of OGs and TGs association of major-signaling pathways in Wilms' tumor cases may aid in disease diagnosis. PBRM1 (up-regulated in 91.67% of cases), ERBB2 and EGFR (down-regulated in 91.66 and 91.66% of cases, respectively) could be marker genes. However, validation of all relevant results in a larger number of samples is required.

Synchronous lung and multiple soft tissue metastases developed from osteosarcoma of tibia: a rare case report and genetic profile analysis

Background

Osteosarcoma is the most common primary malignant bone tumor with a highly metastatic propensity in children and young adolescents. The majority of metastases develope in the lung, while metastases to the extrapulmonary locations have rarely been discussed, especially in skeletal muscle.

Case presentation

We reported a young patient with pathologically diagnosed osteosarcoma of the right tibia who was initially treated with standard chemotherapy and complete surgical resection. However, pulmonary metastases and multiple soft tissue masses in skeletal muscle developed four years after the index surgical resection. Subsequently, a targeted next-generation sequencing assay based on an 806 oncogenes and tumor suppressor genes panel was performed to analyze genetic alterations in this patient with rare metastatic pattern. The genetic analysis revealed canonical somatic mutations of RB1 and germline variants of ALK (c.862 T > C), BLM (c.1021C > T), PTCH1 (c.152_154del), MSH2 (c.14C > A), RAD51C (c.635G > A). Using silico prediction programs, the germline variants of the MSH2 and RAD51C were predicted as “Possibly Damaging” by Polymorphism Phenotyping v2 (PolyPhen-2) and “Tolerated” by Sorting Intolerant from Tolerant (SIFT); BLM was classified as “Tolerated”, while the germline variant of ALK was predicted to be pathogenic by both PolyPhen-2 and SIFT.

Conclusions

Osteosarcoma with extrapulmonary metastases is rare, especially located in the skeletal muscle, which predicts a worse clinical outcome compared with lung-only metastases. The several novel variants of ALK, BLM, PTCH1 in this patient might expand the mutational spectrums of the osteosarcoma. All the results may contribute to a better understanding of the clinical course and genetic characteristics of osteosarcoma patients with metastasis.

Ceritinib in paediatric patients with anaplastic lymphoma kinase-positive malignancies: an open-label, multicentre, phase 1, dose-escalation and dose-expansion study

BACKGROUND

Several paediatric malignancies, including anaplastic large cell lymphoma (ALCL), inflammatory myofibroblastic tumour (IMT), neuroblastoma, and rhabdomyosarcoma, harbour activation of anaplastic lymphoma kinase (ALK) through different mechanisms. Here, we report the safety, pharmacokinetics, and efficacy of ceritinib in paediatric patients with ALK-positive malignancies.

METHODS

This multicentre, open-label, phase 1 trial was done at 23 academic hospitals in ten countries. Children (aged ≥12 months to <18 years) diagnosed with locally advanced or metastatic ALK-positive malignancies that had progressed despite standard therapy, or for which no effective standard therapy were available, were eligible. ALK-positive malignancies were defined as those with ALK rearrangement, amplification, point mutation, or in the case of rhabdomyosarcoma, expression in the absence of any genetic alteration. Eligible patients had evaluable or measurable disease as defined by either Response Evaluation Criteria in Solid Tumours, version 1.1 for patients with non-haematological malignancies, International Neuroblastoma Response Criteria scan for patients with neuroblastoma, or International Working Group criteria for patients with lymphoma. Other eligibility criteria were Karnofsky performance status score of at least 60% for patients older than 12 years or Lansky score of at least 50% for patients aged 12 years or younger. This study included a dose-escalation part, followed by a dose-expansion part, in which all patients received treatment at the recommended dose for expansion (RDE) established in the dose-escalation part. Both parts of the study were done in fasted and fed states. In the dose-escalation part, patients were treated with once-daily ceritinib orally, with dose adjusted for body-surface area, rounded to the nearest multiple of the 50 mg dose strength. The starting dose in the fasted state was 300 mg/m² daily and for the fed state was 320 mg/m² daily. The primary objective of this study was to establish the maximum tolerated dose (ie, RDE) of ceritinib in the fasted and fed states. The RDE was established on the basis of the incidence of dose-limiting toxicities in patients who completed a minimum of 21 days of treatment with safety assessments and at least 75% drug exposure, or who discontinued treatment earlier because of dose-limiting toxicity. Overall response rate (defined as the proportion of patients with a best overall response of complete response or partial response) was a secondary endpoint. Activity and safety analyses were done in all patients who received at least one dose of ceritinib. This trial is registered with ClinicalTrials.gov (NCT01742286) and is completed.

FINDINGS

Between Aug 28, 2013, and Oct 17, 2017, 83 children with ALK-positive malignancies were enrolled to the dose-escalation (n=40) and dose-expansion (n=43) groups. The RDE of ceritinib was established as 510 mg/m² (fasted) and 500 mg/m² (fed). 55 patients (30 with neuroblastoma, ten with IMT, eight with ALCL, and seven with other tumour types) were treated with ceritinib at the RDE (13 patients at 510 mg/m² fasted and 42 patients at 500 mg/m² fed). The median follow-up was 33·3 months (IQR 24·8-39·3) for patients with neuroblastoma, 33·2 months (27·9-35·9) for those with IMT, 34·0 months (21·9-46·4) for those with ALCL, and 27·5 months (22·4-36·9) for patients with other tumour types. An overall response was recorded in six (20%; 95% CI 8-39) of 30 patients with neuroblastoma, seven (70%; 33-93) of ten patients with IMT, six (75%; 35-97) of eight patients with ALCL, and one (14%; <1-58) of seven patients with other tumours. The safety profile of ceritinib was consistent with that observed in adult patients. All patients had at least one adverse event. Grade 3 or 4 adverse events occurred in 67 (81%) of 83 patients and were mostly increases in aminotransferases (alanine aminotransferase increase in 38 [46%] patients and aspartate aminotransferase increase in 27 [33%] patients). At least one serious adverse event was reported in 40 (48%) of 83 patients and 31 (37%) of 83 patients had at least one grade 3 or 4 serious adverse event. 14 (17%) deaths occurred during the study, of which 12 were on-treatment deaths and two were after 30 days of the last dose. Of the 12 on-treatment deaths, ten were due to disease progression (neuroblastoma), one due to sepsis, and one due to intractable hypotension.

INTERPRETATION

Ceritinib 500 mg/m² once daily with food is the recommended dose for paediatric patients with ALK-positive malignancies. Ceritinib showed promising preliminary antitumour activity in patients with ALK-positive refractory or recurrent IMT or ALCL, and in a subset of patients with relapsed or refractory neuroblastoma, with a manageable safety profile. Our data support the notion that ALK inhibitors should be considered in therapeutic strategies for paediatric patients with malignancies with genetic ALK alterations.

FUNDING

Novartis Pharmaceutical Corporation.

Defining Pathological Activities of ALK in Neuroblastoma, a Neural Crest-Derived Cancer

Neuroblastoma is a common extracranial solid tumour of childhood, responsible for 15% of cancer-related deaths in children. Prognoses vary from spontaneous remission to aggressive disease with extensive metastases, where treatment is challenging. Tumours are thought to arise from sympathoadrenal progenitor cells, which derive from an embryonic cell population called neural crest cells that give rise to diverse cell types, such as facial bone and cartilage, pigmented cells, and neurons. Tumours are found associated with mature derivatives of neural crest, such as the adrenal medulla or paraspinal ganglia. Sympathoadrenal progenitor cells express anaplastic lymphoma kinase (ALK), which encodes a tyrosine kinase receptor that is the most frequently mutated gene in neuroblastoma. Activating mutations in the kinase domain are common in both sporadic and familial cases. The oncogenic role of ALK has been extensively studied, but little is known about its physiological role. Recent studies have implicated ALK in neural crest migration and sympathetic neurogenesis. However, very few downstream targets of ALK have been identified. Here, we describe pathological activation of ALK in the neural crest, which promotes proliferation and migration, while preventing differentiation, thus inducing the onset of neuroblastoma. Understanding the effects of ALK activity on neural crest cells will help find new targets for neuroblastoma treatment.

Molecular Basis and Clinical Features of Neuroblastoma

Neuroblastoma, a neoplasm of the sympathetic nervous system, originates from neuroblastoma stem cells during embryogenesis. It exhibits unique clinical features including a tendency for spontaneous regression of tumors in infants and a high frequency of metastatic disease at diagnosis in patients aged over 18 months. Genetic risk factors and epigenetic dysregulation also play a significant role in the development of neuroblastoma. Over the past decade, our understanding of this disease has advanced considerably. This has included the identification of chromosomal copy number aberrations specific to neuroblastoma development, risk groups, and disease stage. However, high-risk neuroblastoma remains a therapeutic challenge for pediatric oncologists. New therapeutic approaches have been developed, either as alternatives to conventional chemotherapy or in combination, to overcome the dismal prognosis. Particularly promising strategies are targeted therapies that directly affect cancer cells or cancer stem cells while exhibiting minimal effect on healthy cells. This review summarizes our understanding of neuroblastoma biology and prognostic features and focuses on novel therapeutic strategies for this intractable disease.

Anaplastic lymphoma kinase (alk), a neuroblastoma associated gene, is expressed in neural crest domains during embryonic development of Xenopus

Neuroblastoma is a neural crest-derived paediatric cancer that is the most common and deadly solid extracranial tumour of childhood. It arises when neural crest cells fail to follow their differentiation program to give rise to cells of the sympathoadrenal lineage. These undifferentiated cells can proliferate and migrate, forming tumours mostly found associated with the adrenal glands. Activating mutations in the kinase domain of anaplastic lymphoma kinase (ALK) are linked to high-risk cases, where extensive therapy is ineffective. However, the role of ALK in embryonic development, downstream signal transduction and in metastatic transformation of the neural crest is poorly understood. Here, we demonstrate high conservation of the ALK protein sequences among vertebrates. We then examine alk mRNA expression in the frog models Xenopus laevis and Xenopus tropicalis. Using in situ hybridisation of Xenopus embryos, we show that alk is expressed in neural crest domains throughout development, suggesting a possible role in neuroblastoma initiation. Lastly, RT-qPCR analyses show high levels of alk expression at tadpole stages. Collectively, these data may begin to elucidate how alk functions in neural crest cells and how its deregulation can result in tumorigenesis.

Potential of German claims data to characterize utilization of new cancer drugs: the example of crizotinib

Aims: Premarketing clinical trials are typically conducted under controlled conditions and in selected study populations, so real-world information on the utilization of new cancer drugs is limited. We aimed to explore the potential of German claims data in this regard, exemplified by the ALK inhibitor crizotinib, used in non-small-cell lung cancer therapy. Materials & methods: We identified patients treated with crizotinib in the German Pharmacoepidemiological Research Database (2004-2017; 20% of the German population) and assessed patient characteristics, treatment and survival. Results: We identified 348 crizotinib-treated patients (56% female; 25% first-line users). After 2 years, overall survival was 48%, with higher survival in men than in women (58 vs 40%). Overall, 76% of patients discontinued crizotinib treatment. Of those, 41% received another ALK inhibitor afterward. Conclusion: The results underline the potential of German claims data for real-world monitoring of oncological drug utilization.

Comparative Genomics within and across Bilaterians Illuminates the Evolutionary History of ALK and LTK Proto-Oncogene Origination and Diversification

Comparative genomic analyses have enormous potential for identifying key genes central to human health phenotypes, including those that promote cancers. In particular, the successful development of novel therapeutics using model species requires phylogenetic analyses to determine molecular homology. Accordingly, we investigate the evolutionary histories of anaplastic lymphoma kinase (ALK)—which can underlie tumorigenesis in neuroblastoma, nonsmall cell lung cancer, and anaplastic large-cell lymphoma—its close relative leukocyte tyrosine kinase (LTK) and their candidate ligands. Homology of ligands identified in model organisms to those functioning in humans remains unclear. Therefore, we searched for homologs of the human genes across metazoan genomes, finding that the candidate ligands Jeb and Hen-1 were restricted to nonvertebrate species. In contrast, the ligand augmentor (AUG) was only identified in vertebrates. We found two ALK-like and four AUG-like protein-coding genes in lamprey. Of these six genes, only one ALK-like and two AUG-like genes exhibited early embryonic expression that parallels model mammal systems. Two copies of AUG are present in nearly all jawed vertebrates. Our phylogenetic analysis strongly supports the presence of previously unrecognized functional convergences of ALK and LTK between actinopterygians and sarcopterygians—despite contemporaneous, highly conserved synteny of ALK and LTK. These findings provide critical guidance regarding the propriety of fish and mammal models with regard to model organism-based investigation of these medically important genes. In sum, our results provide the phylogenetic context necessary for effective investigations of the functional roles and biology of these critically important receptors.

Molecular targeting therapies for neuroblastoma: Progress and challenges

There is an urgent need to identify novel therapies for childhood cancers. Neuroblastoma is the most common pediatric solid tumor, and accounts for ~15% of childhood cancer‐related mortality. Neuroblastomas exhibit genetic, morphological and clinical heterogeneity, which limits the efficacy of existing treatment modalities. Gaining detailed knowledge of the molecular signatures and genetic variations involved in the pathogenesis of neuroblastoma is necessary to develop safer and more effective treatments for this devastating disease. Recent studies with advanced high‐throughput “omics” techniques have revealed numerous genetic/genomic alterations and dysfunctional pathways that drive the onset, growth, progression, and resistance of neuroblastoma to therapy. A variety of molecular signatures are being evaluated to better understand the disease, with many of them being used as targets to develop new treatments for neuroblastoma patients. In this review, we have summarized the contemporary understanding of the molecular pathways and genetic aberrations, such as those in MYCN, BIRC5, PHOX2B, and LIN28B, involved in the pathogenesis of neuroblastoma, and provide a comprehensive overview of the molecular targeted therapies under preclinical and clinical investigations, particularly those targeting ALK signaling, MDM2, PI3K/Akt/mTOR and RAS‐MAPK pathways, as well as epigenetic regulators. We also give insights on the use of combination therapies involving novel agents that target various pathways. Further, we discuss the future directions that would help identify novel targets and therapeutics and improve the currently available therapies, enhancing the treatment outcomes and survival of patients with neuroblastoma.

The novel ALK inhibitor ZX-29 induces apoptosis through inhibiting ALK and inducing ROS-mediated endoplasmic reticulum stress in Karpas299 cells

It is a well-known fact that 60%-85% of anaplastic large cell lymphoma (ALCL) is mainly driven by the anaplastic lymphoma kinase (ALK) fusion protein. Although ALK-positive ALCL patients respond significantly to ALK inhibitors, the development of resistance is inevitable, which requires the development of new therapeutic strategies for ALK-positive ALCL. Here, we investigated the anticancer activities of N-(2((5-chloro-2-((2-methoxy-6-(4-methylpiperazin-1-yl)pyridin-3yl)amino)pyrimidin-4-yl)amino)phenyl)methanesulfonamide (ZX-29), a newly synthesized ALK inhibitor, against nucleophosmin-ALK-positive cell line Karpas299. We demonstrated that ZX-29 decreased Karpas299 cells growth and had better cytotoxicity than ceritinib, which was mediated through downregulating the expression of ALK and related proteins, inducing cell cycle arrest, and promoting cell apoptosis. Moreover, ZX-29-induced cell apoptosis by inducing endoplasmic reticulum stress (ERS). In addition, ZX-29 increased the generation of reactive oxygen species (ROS), and cells pretreatment with N-acetyl- l-cysteine could attenuate ZX-29-induced cell apoptosis and ERS. Taken together, ZX-29 inhibited Karpas299 cell proliferation and induced apoptosis through inhibiting ALK and its downstream protein expression and inducing ROS-mediated ERS. Therefore, our results provide evidence for a novel antitumor candidate for the further investigation.

Targeted fusion analysis can aid in the classification and treatment of pediatric glioma, ependymoma, and glioneuronal tumors

BACKGROUND

The use of next-generation sequencing for fusion identification is being increasingly applied and aids our understanding of tumor biology. Some fusions are responsive to approved targeted agents, while others have future potential for therapeutic targeting. Although some pediatric central nervous system tumors may be cured with surgery alone, many require adjuvant therapy associated with acute and long-term toxicities. Identification of targetable fusions can shift the treatment paradigm toward earlier integration of molecularly targeted agents.

METHODS

Patients diagnosed with glial, glioneuronal, and ependymal tumors between 2002 and 2019 were retrospectively reviewed for fusion testing. Testing was done primarily using the ArcherDx FusionPlex Solid Tumor panel, which assesses fusions in 53 genes. In contrast to many previously published series chronicling fusions in pediatric patients, we compared histological features and the tumor classification subtype with the specific fusion identified.

RESULTS

We report 24 cases of glial, glioneuronal, or ependymal tumors from pediatric patients with identified fusions. With the exception of BRAF:KIAA1549 and pilocytic/pilomyxoid astrocytoma morphology, and possibly QKI-MYB and angiocentric glioma, there was not a strong correlation between histological features/tumor subtype and the specific fusion. We report the unusual fusions of PPP1CB-ALK, CIC-LEUTX, FGFR2-KIAA159, and MN1-CXXC5 and detail their morphological features.

CONCLUSIONS

Fusion testing proved to be informative in a high percentage of cases. A large majority of fusion events in pediatric glial, glioneuronal, and ependymal tumors can be identified by relatively small gene panels.

Hydrogel 3D in vitro tumor models for screening cell aggregation mediated drug response

Hydrogel-based 3D in vitro models comprising tumor ECM-mimetic biomaterials exhibit differential responses to therapeutics according to cancer cells cellular aggregation state.

The Transcriptional Roles of ALK Fusion Proteins in Tumorigenesis

Anaplastic lymphoma kinase (ALK) is a tyrosine kinase involved in neuronal and gut development. Initially discovered in T cell lymphoma, ALK is frequently affected in diverse cancers by oncogenic translocations. These translocations involve different fusion partners that facilitate multimerisation and autophosphorylation of ALK, resulting in a constitutively active tyrosine kinase with oncogenic potential. ALK fusion proteins are involved in diverse cellular signalling pathways, such as Ras/extracellular signal-regulated kinase (ERK), phosphatidylinositol 3-kinase (PI3K)/Akt and Janus protein tyrosine kinase (JAK)/STAT. Furthermore, ALK is implicated in epigenetic regulation, including DNA methylation and miRNA expression, and an interaction with nuclear proteins has been described. Through these mechanisms, ALK fusion proteins enable a transcriptional programme that drives the pathogenesis of a range of ALK-related malignancies.

ALK and GSK3: Shared Features of Neuroblastoma and Neural Crest Cells

Neuroblastoma is one of the most common and deadly childhood cancers. Neuroblastoma arises from transformed cells of the neural crest lineage. Outcomes of the disease vary greatly, ranging from spontaneous regression to aggressive metastases. While this variability may reflect the inherent migratory capabilities and multipotency of neural crest cells, there have been few direct comparisons between neuroblastoma and embryonic neural crest cells, in part because of the limited in vivo accessibility of the mammalian neural crest lineage. Our recent studies demonstrate a novel link between anaplastic lymphoma kinase (ALK) and glycogen synthase kinase 3 (GSK3). Our work suggests that ALK-dependent regulation of GSK3 via tyrosine phosphorylation may alter the substrate specificity of GSK3, thus regulating cytoskeletal dynamics in migrating neural crest cells.

The role of anaplastic lymphoma kinase in pediatric cancers

The anaplastic lymphoma kinase (ALK) gene was initially identified as a fusion partner of the nucleophosmin gene in anaplastic large-cell lymphoma with t(2;5)(p23;q35) translocation, and then described with different genetic abnormalities in a number of tumors. Although ALK is known to be involved in the pathogenesis of neuroblastoma through activating mutations or gene amplification, its role in the pathogenesis of other pediatric cancers is still elusive. In addition to neuroblastoma, the high-grade amplification of ALK has been described in a subset of rhabdomyosarcoma cases. Normal ALK protein expression is restricted to the nervous systems of adult mammals, but the aberrant expression of ALK has been observed in a variety of pediatric cancers, including glioma and Ewing sarcoma. The discovery of oncogenic activation of ALK in neuroblastoma suggests that this cancer could be potentially treated with an ALK inhibitor, as could other cancers, such as non-small-cell lung cancer and anaplastic large-cell lymphoma. However, cellular responses to mutant ALK are complex when compared to rearranged ALK, and treatment remains a challenge. This review focuses on the biology of ALK in pediatric cancers and possible therapeutic strategies for ALK-associated tumors.