The ALK(F1174L) mutation potentiates the oncogenic activity of MYCN in neuroblastoma

The ALK(F1174L) mutation is associated with intrinsic and acquired resistance to crizotinib and cosegregates with MYCN in neuroblastoma. In this study, we generated a mouse model overexpressing ALK(F1174L) in the neural crest. Compared to ALK(F1174L) and MYCN alone, co-expression of these two oncogenes led to the development of neuroblastomas with earlier onset, higher penetrance, and enhanced lethality. ALK(F1174L)/MYCN tumors exhibited increased MYCN dosage due to ALK(F1174L)-induced activation of the PI3K/AKT/mTOR and MAPK pathways, coupled with suppression of MYCN pro-apoptotic effects. Combined treatment with the ATP-competitive mTOR inhibitor Torin2 overcame the resistance of ALK(F1174L)/MYCN tumors to crizotinib. Our findings demonstrate a pathogenic role for ALK(F1174L) in neuroblastomas overexpressing MYCN and suggest a strategy for improving targeted therapy for ALK-positive neuroblastoma.     

Activated Alk triggers prolonged neurogenesis and Ret upregulation providing a therapeutic target in ALK-mutated neuroblastoma

Activating mutations of the ALK (Anaplastic lymphoma Kinase) gene have been identified in sporadic and familial cases of neuroblastoma, a cancer of early childhood arising from the sympathetic nervous system (SNS). To decipher ALK function in neuroblastoma predisposition and oncogenesis, we have characterized knock-in (KI) mice bearing the two most frequent mutations observed in neuroblastoma patients. A dramatic enlargement of sympathetic ganglia is observed in Alk^F1178L mice from embryonic to adult stages associated with an increased proliferation of sympathetic neuroblasts from E14.5 to birth. In a MYCN transgenic context, the F1178L mutation displays a higher oncogenic potential than the R1279Q mutation as evident from a shorter latency of tumor onset. We show that tumors expressing the R1279Q mutation are sensitive to ALK inhibition upon crizotinib treatment. Furthermore, our data provide evidence that activated ALK triggers RET upregulation in mouse sympathetic ganglia at birth as well as in murine and human neuroblastoma. Using vandetanib, we show that RET inhibition strongly impairs tumor growth in vivo in both MYCN/KI Alk^R1279Q and MYCN/KI Alk^F1178L mice. Altogether, our findings demonstrate the critical role of activated ALK in SNS development and pathogenesis and identify RET as a therapeutic target in ALK mutated neuroblastoma.     

Targeting ALK: a promising strategy for the treatment of non-small cell lung cancer, non-Hodgkin’s lymphoma, and neuroblastoma

Anaplastic lymphoma kinase (ALK) is a tyrosine kinase receptor that affects a number of biological and biochemical functions through normal ligand-dependent signaling. It has oncogenic functions in a number of tumors including non-small cell lung cancer (NSCLC), anaplastic large cell lymphoma, and neuroblastoma when altered by translocation or amplification or mutation. On August 2011, a small molecule inhibitor against ALK, crizotinib, was approved for therapy against NSCLC with ALK translocations. As we determine the molecular heterogeneity of tumors, the potential of ALK as a relevant therapeutic target in a number of malignancies has become apparent. This review will discuss some of the tumor types with oncogenic ALK alterations. The activity and unique toxicities of crizotinib are described, along with potential mechanisms of resistance and new therapies beyond crizotinib.     

Detection of ALK and KRAS Mutations in Circulating Tumor DNA of Patients With Advanced ALK-Positive NSCLC With Disease Progression During Crizotinib Treatment

BackgroundIn patients with anaplastic lymphoma kinase (ALK)-positive non–small-cell lung cancer (NSCLC), disease progression occurs after a median of 9 to 10 months of crizotinib treatment. Several mechanisms of resistance have been identified and include ALK mutations and amplification or the activation of bypassing signaling pathways. Rebiopsy in NSCLC patients represents a critical issue and the analysis of circulating cell-free DNA (cfDNA) has a promising role for the identification of resistance mechanisms.Patients and MethodsTwenty patients with advanced ALK-positive NSCLC were enrolled after disease progression during crizotinib treatment; cfDNA was analyzed using digital droplet polymerase chain reaction (BioRad, Hercules, CA) for ALK (p.L1196M, p.G1269A, and p.F1174L) and Kirsten rat sarcoma (KRAS) (codons 12 and 13) mutations.ResultsALK secondary mutations (p.L1196M, p.G1269A, and p.F1174L) were identified in 5 patients; 1 patient had 2 ALK mutations (p.L1196M and p.G1269A). Overall, 10 patients presented KRAS mutations (7 p.G12D, 2 p.G12V, and 1 p.G12C mutations, respectively). In 3 patients KRAS mutations were associated with ALK mutations. cfDNA was monitored during the treatment with second-generation ALK inhibitors and the amount of ALK as well as KRAS mutations decreased along with tumor regression.ConclusionALK and KRAS mutations are associated with acquired resistance to crizotinib in ALK-positive NSCLC. In particular, ALK acquired mutations can be detected in plasma and could represent a promising tumor marker for response monitoring.     

Hyperactivation of Alk induces neonatal lethality in knock-in AlkF1178L mice

The ALK (Anaplastic Lymphoma Kinase) gene encodes a tyrosine kinase receptor preferentially expressed in the central and peripheral nervous systems. A syndromic presentation associating congenital neuroblastoma with severe encephalopathy and an abnormal shape of the brainstem has been described in patients harbouring de novo germline F1174V and F1245V ALK mutations. Here, we investigated the phenotype of knock-in (KI) mice bearing the Alk^F1178L mutation (F1174L in human). Although heterozygous KI mice did not reproduce the severe breathing and feeding difficulties observed in human patients, behavioral tests documented a reduced activity during dark phases and an increased anxiety of mutated mice. Matings of heterozygotes yielded the expected proportions of wild-type, heterozygotes and homozygotes at birth but a high neonatal lethality was noticed for homozygotes. We documented Alk expression in several motor nuclei of the brainstem involved in the control of sucking and swallowing. Evaluation of basic physiological functions 12 hours after birth revealed slightly more apneas but a dramatic reduced milk intake for homozygotes compared to control littermates. Overall, our data demonstrate that Alk activation above a critical threshold is not compatible with survival in mice, in agreement with the extremely severe phenotype of patients carrying aggressive de novo ALK germline mutations.     

Copy number status and mutation analyses of anaplastic lymphoma kinase (ALK) gene in 90 sporadic neuroblastoma tumors

Somatic and germline mutations of the anaplastic lymphoma kinase (ALK) gene were recently described in neuroblastoma (NB). In this study, we investigated the association of ALK copy number alterations with copy number status 2p24.1 amplicon harboring DEAD box polypeptide 1 (DDX1), MYCN and neuroblastoma-amplified (NAG) genes in 90 primary tumors of sporadic NB cases by multiplex ligation-dependent probe amplification (MLPA). We also performed mutation analysis of ALK gene by directly sequencing the exons 20-28 which cover the region that encodes juxtamembrane and kinase domains. A total of 39 (43.3%) NB cases revealed copy numbers alterations of ALK gene. There was highly significant association of ALK copy number gains with gains of one or more of the genes at 2p24.1 (DDX1, MYCN or NAG) in MYCN unamplified tumors (P < 0.000). In addition, 15 of 17 MYCN amplified cases (88.2%) had aberrant ALK status. Solitary gain of ALK with normal copy number status of all other genes was observed only in one case. DNA sequencing of exons 20-28 of ALK revealed two different nucleotide changes in three cases leading to amino acid substitutions of F1245V and R1275Q in tyrosine kinase domain. In conclusion, the frequency of ALK mutations in NB is low and solitary copy number change of it is rarely observed.     

A Case of Orbital Metastasis as Disease Progression of Anaplastic Lymphoma Kinase-Positive Lung Cancer Treated with Crizotinib

Orbital metastasis of lung cancer is rare. It often causes visual disorder. To date, there are only a few case reports. Crizotinib is an anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitor that leads to responses in most patients with ALK-positive non-small-cell lung cancer. Visual disorder is one of the popular adverse events of crizotinib, but the symptom almost decreases over time. We report a case of orbital metastasis as the disease progression of ALK-positive lung cancer treated with crizotinib. It should be kept in mind that orbital metastasis can be the disease progression of lung adenocarcinoma with ALK translocation treated with crizotinib. When physicians encounter a patient receiving crizotinib with visual disorder, we must distinguish between adverse events and orbital metastasis.Key Words: Orbital metastasis, Crizotinib, Adverse event, Anaplastic lymphoma kinase, Lung cancer, Lung adenocarcinoma     

Precision medicine against <Emphasis Type="Italic">ALK</Emphasis>-positive non-small cell lung cancer: beyond crizotinib

Anaplastic lymphoma kinase (ALK) rearrangements represent the molecular driver of a subset of non-small cell lung cancers (NSCLCs). Despite the initial response, virtually all ALK-positive patients develop an acquired resistance to the ALK inhibitor crizotinib, usually within 12 months. Several next-generation ALK inhibitors have been developed in order to overcome crizotinib limitation, providing an unprecedented survival for this subset of patients. The aim of this review to summarize the current knowledge on ALK tyrosine kinase inhibitors (TKIs) in the treatment of advanced ALK-positive NSCLC, focusing on the role of novel ALK inhibitors in this setting. In addition, we will discuss their role in the pharmacological management of ALK-positive brain metastasis. Next-generation ALK inhibitors showed an impressive clinical activity in ALK-positive NSCLC, also against the sanctuary site of CNS. Sequential therapy with ALK TKIs appears to be effective in patients who fail a first ALK TKI and translates in clinically meaningful benefit. However, these agents display different activity profiles against crizotinib resistance mutation; therefore re-genotyping the disease at progression in order to administer the right TKI to the right patient is going to be necessary to correctly tailor the treatment. To avoid repeated invasive procedure, noninvasive methods to detect and monitor ALK rearrangement are under clinical investigation.     

The accelerated path of ceritinib: Translating pre-clinical development into clinical efficacy

The discovery of anaplastic lymphoma kinase (ALK)-rearranged non–small-cell lung cancer (NSCLC) in 2007 led to the development and subsequent approval of the ALK inhibitor crizotinib in 2011. However, despite its clinical efficacy, resistance to crizotinib invariably develops. There is now a next generation of ALK inhibitors, including two that have been approved—ceritinib and alectinib—and others that are in development—brigatinib, lorlatinib and X-396. Ceritinib and the other next-generation ALK inhibitors are more potent than crizotinib and can overcome tumor cell resistance mechanisms. Ceritinib gained US Food and Drug Administration approval in 2014 following accelerated review for the treatment of patients with ALK-positive (ALK+) metastatic NSCLC who have progressed on or are intolerant to crizotinib. In pre-clinical studies, it demonstrated more potent inhibition of ALK than crizotinib in enzymatic assays, more durable responses in xenograft models and the ability to potently overcome crizotinib resistance mutations in vitro (including the gatekeeper mutation). There is also evidence for ceritinib penetration across the blood-brain barrier. In clinical trials, ceritinib has demonstrated durable responses and progression-free survival in ALK-inhibitor–pre-treated and –naïve NSCLC patients, including high overall and intracranial response rates in those with central nervous system metastases. Selective gastrointestinal toxicity of ceritinib, such as diarrhea, nausea and vomiting is generally manageable with prophylactic medication and prompt dose reduction or interruption. Future progress in treating ALK+ NSCLC will focus on determining the optimal sequencing of therapies and strategies to overcome acquired resistance, an ongoing challenge in treating ALK-mutation–driven tumors.     

Outcomes According to ALK Status Determined by Central Immunohistochemistry or Fluorescence In Situ Hybridization in Patients With ALK-Positive NSCLC Enrolled in the Phase 3 ALEX Study

IntroductionWe retrospectively examined progression-free survival (PFS) and response by ALK fluorescence in situ hybridization (FISH) status in patients with advanced ALK immunohistochemistry (IHC)-positive NSCLC in the ALEX study.MethodsA total of 303 treatment-naive patients were randomized to receive twice-daily alectinib 600 mg or crizotinib 250 mg. ALK status was assessed centrally using Ventana ALK (D5F3) CDx IHC and Vysis ALK Break Apart FISH Probe Kit. Primary end point is investigator-assessed PFS. Secondary end points of interest are objective response rate and duration.ResultsInvestigator-assessed PFS was significantly prolonged with alectinib versus crizotinib in ALK IHC-positive and FISH-positive tumors (n = 203, 67%) (hazard ratio [HR] = 0.37, 95% confidence interval [CI]: 0.25–0.56; p < 0.0001) and ALK IHC-positive and FISH-uninformative tumors (n = 61, 20%) (HR = 0.39, 95% CI: 0.20–0.78) but not in ALK IHC-positive and FISH-negative tumors (n = 39, 13%) (HR = 1.33, 95% CI: 0.6–3.2). Objective response rates were higher with alectinib versus crizotinib in ALK IHC-positive and FISH-positive tumors (90.6% versus 81.4%; stratified OR = 2.22, 95% CI: 0.97–5.07) and ALK IHC-positive and FISH-uninformative tumors (96.0% versus 75.0%; OR = 9.29, 95% CI: 1.05–81.88) but not in ALK IHC-positive and FISH-negative tumors (28.6% versus 44.4%; OR = 0.45, 95% CI: 0.12–1.74). Next-generation sequencing was performed in 35 of 39 patients with ALK IHC-positive and FISH-negative tumors; no ALK fusion was identified in 20 of 35 patients (57.1%) by next-generation sequencing, but 10 of 20 (50.0%) had partial response or stable disease.ConclusionsOutcomes of patients with ALK IHC-positive and FISH-positive and ALK IHC-positive and FISH-uninformative NSCLC were similar to those of the overall ALEX population. These results suggest that Ventana ALK IHC is a standard testing method for selecting patients for treatment with alectinib.     

A Sensitive ALK Immunohistochemistry Companion Diagnostic Test Identifies Patients Eligible for Treatment with Crizotinib

IntroductionThe availability of high-quality, rigorously validated diagnostic tests that can be broadly implemented is necessary to efficiently identify patients with anaplastic lymphoma kinase (ALK)-positive NSCLC who can potentially benefit from treatment with crizotinib. Here we present data on the recently approved Ventana ALK (D5F3) CDx Assay (Ventana Medical Systems, Tucson, AZ), the only immunohistochemistry (IHC)-based assay linked to treatment outcome.MethodsNSCLC specimens prospectively tested for anaplastic lymphoma receptor tyrosine kinase gene (ALK) status by flourescent in situ hybridization (FISH) in the PROFILE 1014 clinical trial of crizotinib versus chemotherapy (N = 1018, including 179 ALK-positive and 754 ALK-negative specimens) were evaluated using the ALK (D5F3) CDx assay. Hazard ratios for progression-free survival comparing crizotinib and chemotherapy for ALK IHC–positive patients and ALK FISH–positive patients, as well as for concordance with the enrollment ALK FISH assay, were determined.ResultsResults from both assays were obtained for 933 cases. Percent positive, negative, and overall agreement rates were 86.0% , 96.3%, and 94.3%, respectively. There were 53 discrepant cases, of which 25 were ALK FISH–positive/ALK IHC–negative and 28 were ALK FISH–negative/ALK IHC–positive. The hazard ratios using observed outcomes were 0.401 for ALK FISH–positive/ALK IHC–positive cases and 0.407 for all ALK FISH–positive cases tested with ALK IHC versus 0.454 for all ALK FISH–positive cases enrolled in the trial. Outcome data for ALK FISH–negative/ALK IHC–positive cases were not available for analysis. Between-reader agreement rates for ALK IHC involving three independent laboratories exceeded 98%.ConclusionsThe ALK (D5F3) CDx assay is a stand-alone companion diagnostic test for identification of patients for treatment with crizotinib. This automated assay provides an effective option to accurately and rapidly identify patients with ALK-positive NSCLC. The simple binary scoring algorithm results in high reader-to-reader precision.     

ALK Inhibitors: What Is the Best Way to Treat Patients With ALK+ Non–Small-Cell Lung Cancer?

Genetic insight into the pathogenesis of lung cancer has paved the way for a new era in its treatment. Recently, anaplastic lymphoma kinase (ALK) has been identified as exerting a potent transforming effect through genetic rearrangement in patients with lung cancer. Preclinical and single-arm phase I studies have shown that patients with ALK-rearranged non–small cell lung cancer (NSCLC) can be successfully treated with crizotinib. Furthermore, a phase III randomized study indicated that crizotinib is superior to standard chemotherapy in the treatment of patients with NSCLC harboring the ALK rearrangement who had received 1 previous platinum-based chemotherapy. Despite the excellent efficacy of crizotinib in patients with ALK-positive (ALK⁺) lung cancer, resistance mechanisms—such as secondary mutations in the ALK gene, the activation of other oncogenes, and so on—have been identified as conferring resistance to crizotinib. Second-generation ALK inhibitors, such as alectinib and ceritinib, have been shown to be effective not only in crizotinib-naive patients but also in those resistant to crizotinib. Therefore, although some agents specifically targeting ALK have been developed and their efficacy has been documented, how ALK inhibitors should be administered in the setting of ALK-rearranged NSCLC remains to be fully elucidated. Can second-generation ALK inhibitors replace crizotinib? Is crizotinib just a first-generation ALK inhibitor? Is the sequential use of crizotinib and second-generation ALK inhibitors the best method? In this article, we review the preclinical and clinical results regarding crizotinib and second-generation ALK inhibitors, as well as the resistance mechanisms, and discuss the best methods for treating patients with ALK⁺ NSCLC.     

New therapeutic strategies in neuroblastoma: combined targeting of a novel tyrosine kinase inhibitor and liposomal siRNAs against ALK

Many different aberrations in the Anaplastic Lymphoma Kinase (ALK) were found to be oncogenic drivers in several cancers including neuroblastoma (NB), therefore ALK is now considered a critical player in NB oncogenesis and a promising therapeutic target. The ALK-inhibitor crizotinib has a limited activity against the various ALK mutations identified in NB patients.We tested: the activity of the novel ALK-inhibitor X-396 administered alone or in combination with Targeted Liposomes carrying ALK-siRNAs (TL[ALK-siRNA]) that are active irrespective of ALK gene mutational status; the pharmacokinetic profiles and the biodistribution of X-396; the efficacy of X-396 versus crizotinib treatment in NB xenografts; whether the combination of X-396 with the TL[ALK-siRNA] could promote long-term survival in NB mouse models.X-396 revealed good bioavailability, moderate half-life, high mean plasma and tumor concentrations. X-396 was more effective than crizotinib in inhibiting in vitro cell proliferation of NB cells and in reducing tumor volume in subcutaneous NB models in a dose-dependent manner.In orthotopic NB xenografts, X-396 significantly increased life span independently of the ALK mutation status. In combination studies, all effects were significantly improved in the mice treated with TL[ALK-siRNA] and X-396 compared to mice receiving the single agents.Our findings provide a rational basis to design innovative molecular-based treatment combinations for clinical application in ALK-driven NB tumors.     

Dual ALK and EGFR inhibition targets a mechanism of acquired resistance to the tyrosine kinase inhibitor crizotinib in ALK rearranged lung cancer

Introduction

The multitargeted tyrosine kinase inhibitor (TKI) crizotinib is active against ALK translocated non-small-cell lung cancer (NSCLC); however acquired resistance invariably develops over time. ALK mutations have previously been implicated in only a third of resistant tumors. We sought to evaluate alternative mechanisms of resistance and preclinical strategies to overcome these in a cell line driven by EML4-ALK.

Methods

We selected the NSCLC cell line NCI-H3122 (H3122: EML4-ALK E13;A20) and derived resistant variants that were able to grow in the presence of 1 μM crizotinib. These were analyzed for ALK mutations, sensitivity to crizotinib in combination with other TKIs, and for activation of alternative tyrosine kinases.

Results

All H3122 crizotinib resistant (CR) clones lacked amplification or mutations in the kinase domain of ALK. To evaluate if possible alternative kinases functioned as “bypass” tracks for downstream signaling activation in these resistance cells, we performed of phosho-receptor tyrosine kinase array that demonstrated that CR clones had higher phospho-EGFR signals than H3122 cells before and after exposure to crizotinib. A functional approach of dual ALK TKI (with crizotinib) with combinatory TKI inhibition was used as a secondary screen for possible targets. Crizotinib + erlotinib (reversible EGFR TKI) and crizotinib + afatinib (irreversible EGFR/ERBB2 TKI) were able to inhibit the growth of H3122 CR clones, confirming EGFR activation as a mechanism of resistance. The removal of crizotinib from the culture media re-sensitized CR cells to crizotinib.

Conclusions

We identified activation of EGFR as a mechanism of resistance to crizotinib in preclinical models of ALK translocated NSCLC. If EGFR activation is confirmed as a predominant mechanism of ALK TKI-induced resistance in patient-derived tumors, the use of ALK plus EGFR TKIs could be explored for this important cohort of NSCLCs.     

Sequential Therapy with Crizotinib and Alectinib in ALK-Rearranged Non–Small Cell Lung Cancer—A Multicenter Retrospective Study

IntroductionAlectinib and crizotinib have been approved for the therapy of NSCLC caused by anaplastic lymphoma kinase gene (ALK) rearrangement. The effect of alectinib or crizotinib on overall survival (OS) in patients with ALK-rearranged NSCLC remains unknown.MethodsA multicenter retrospective study was conducted to compare OS between patients receiving alectinib and crizotinib and between patients treated with alectinib and those treated sequentially with crizotinib and then alectinib after crizotinib failure. The time to treatment failure (TTF), progression-free survival (PFS), and OS were compared.ResultsSixty-one patients with ALK-rearranged NSCLC were enrolled. Forty-six patients were treated with anaplastic lymphoma kinase (ALK) inhibitors (31 with crizotinib, 28 with alectinib, and 13 with both ALK inhibitors). The response rate was 66.7% for the crizotinib-treated group and 80.8% for the alectinib-treated group. Among all patients, TTF and PFS were significantly prolonged in the alectinib-treated group compared with in the crizotinib-treated group. Subgroup analyses revealed significantly prolonged TTF for alectinib compared with crizotinib therapy in the ALK inhibitor–naive population. OS was significantly longer in the alectinib-treated group than in the crizotinib-treated group. The TTF and OS of patients treated sequentially with crizotinib and then with alectinib after crizotinib failure tended to be longer than those of patients treated with alectinib alone.ConclusionsTherapy with alectinib alone was significantly superior to therapy with crizotinib alone in terms of TTF, PFS, and OS, and sequential therapy with crizotinib and alectinib after crizotinib failure tended to provide a better OS benefit than did therapy with alectinib alone in patients with ALK-positive NSCLC. However, large-scale prospective studies are needed to confirm these observations.     

Activity of Crizotinib (PF02341066), a Dual Mesenchymal-Epithelial Transition (MET) and Anaplastic Lymphoma Kinase (ALK) Inhibitor,in a Non-small Cell Lung Cancer Patient with De Novo MET Amplification

Crizotinib is a dual MET and ALK inhibitor. Currently, clinical development of crizotinib is focused primarily on ALK rearranged non-small cell lung cancer (NSCLC). Here we report an NSCLC patient with de novo MET amplification but no ALK rearrangement who achieved a rapid and durable response to crizotinib indicating is also a bona fide MET inhibitor.     

Catalytic mTOR inhibitors can overcome intrinsic and acquired resistance to allosteric mTOR inhibitors

We tested the antitumor efficacy of mTOR catalytic site inhibitor MLN0128 in models with intrinsic or acquired rapamycin-resistance. Cell lines that were intrinsically rapamycin-resistant as well as those that were intrinsically rapamycinsensitive were sensitive to MLN0128 in vitro. MLN0128 inhibited both mTORC1 and mTORC2 signaling, with more robust inhibition of downstream 4E-BP1 phosphorylation and cap-dependent translation compared to rapamycin in vitro. Rapamycin-sensitive BT474 cell line acquired rapamycin resistance (BT474 RR) with prolonged rapamycin treatment in vitro. This cell line acquired an mTOR mutation (S2035F) in the FKBP12-rapamycin binding domain; mTORC1 signaling was not inhibited by rapalogs but was inhibited by MLN0128. In BT474 RR cells, MLN0128 had significantly higher growth inhibition compared to rapamycin in vitro and in vivo. Our results demonstrate that MLN0128 may be effective in tumors with intrinsic as well as acquired rapalog resistance. mTOR mutations are a mechanism of acquired resistance in vitro; the clinical relevance of this observation needs to be further evaluated.