Non-Canonical Thinking for Targeting ALK-Fusion Onco-Proteins in Lung Cancer.

Anaplastic lymphoma kinase (ALK) gene rearrangements have been identified in lung cancer at 3-7% frequency, thus representing an important subset of genetic lesions that drive oncogenesis in this disease. Despite the availability of multiple FDA-approved small molecule inhibitors targeting ALK fusion proteins, drug resistance to ALK kinase inhibitors is a common problem in clinic. Thus, there is an unmet need to deepen the current understanding of genomic characteristics of ALK rearrangements and to develop novel therapeutic strategies that can overcome ALK inhibitor resistance. In this review, we present the genomic landscape of ALK fusions in the context of co-occurring mutations with other cancer-related genes, pointing to the central role of genetic epistasis (gene-gene interactions) in ALK-driven advanced-stage lung cancer. We discuss the possibility of targeting druggable domains within ALK fusion partners in addition to available strategies inhibiting the ALK kinase domain directly. Finally, we examine the potential of targeting ALK fusion-specific neoantigens in combination with other treatments, a strategy that could open a new avenue for the improved treatment of ALK positive lung cancer patients

Early and late effects of pharmacological ALK inhibition on the neuroblastoma transcriptome

Background: Neuroblastoma is an aggressive childhood malignancy of the sympathetic nervous system. Despite multi-modal therapy, survival of high-risk patients remains disappointingly low, underscoring the need for novel treatment strategies. The discovery of ALK activating mutations opened the way to precision treatment in a subset of these patients. Previously, we investigated the transcriptional effects of pharmacological ALK inhibition on neuroblastoma cell lines, six hours after TAE684 administration, resulting in the 77-gene ALK signature, which was shown to gradually decrease from 120 minutes after TAE684 treatment, to gain deeper insight into the molecular effects of oncogenic ALK signaling. Aim: Here, we further dissected the transcriptional dynamic profiles of neuroblastoma cells upon TAE684 treatment in a detailed timeframe of ten minutes up to six hours after inhibition, in order to identify additional early targets for combination treatment. Results: We observed an unexpected initial upregulation of positively regulated MYCN target genes following subsequent downregulation of overall MYCN activity. In addition, we identified adrenomedullin (ADM), previously shown to be implicated in sunitinib resistance, as the earliest response gene upon ALK inhibition. Conclusions: We describe the early and late effects of ALK inhibitor TAE684 treatment on the neuroblastoma transcriptome. The observed unexpected upregulation of ADM warrants further investigation in relation to putative ALK resistance in neuroblastoma patients currently undergoing ALK inhibitor treatment

Symptomatic CNS Radiation Necrosis Requiring Neurosurgical Resection During Treatment with Lorlatinib in ALK-Rearranged NSCLC: A Report of Two Cases.

Central nervous system (CNS) metastasis carries a significant morbidity and mortality in anaplastic lymphoma kinase (ALK)-rearranged non-small cell lung cancer (NSCLC). Next-generation ALK tyrosine kinase inhibitors (TKIs) are highly CNS-penetrant and have demonstrated remarkable intracranial activity across clinical studies, and yet radiation remains the mainstay of treatment modality against CNS metastasis. We have previously reported alectinib can induce CNS radiation necrosis even after a remote history of radiation (7 years post-radiation). Lorlatinib is another potent next-generation ALK TKI that can overcome many ALK resistance mutations and has been shown to have excellent activity in patients with baseline CNS metastasis. Here we report two ALK-rearranged NSCLC patients who developed radiation necrosis shortly after initiating lorlatinib following progression on the sequential treatment of crizotinib, alectinib, and brigatinib. In both cases, radiation necrosis is evidenced by serial MRI images and histological examination of the resected CNS metastasis that had previously been radiated. Our cases highlight the importance of recognizing CNS radiation necrosis that may mimic disease progression in ALK-rearranged NSCLC treated with and potentially precipated by next-generation ALK TKIs

Silenced Expression of NFKBIA in Lung Adenocarcinoma Patients with a Never-smoking History

Nuclear factor of κ-light polypeptide gene enhancer in B cells inhibitor α (NFKBIA), which is a tumor suppressor gene, was found to be silenced in lung adenocarcinomas. We examined NFKBIA expression, mutations in the EGFR and K-ras genes, and EML4-ALK fusion in 101 resected lung adenocarcinoma samples from never-smokers. NFKBIA expression was evaluated using immunohistochemistry. NFKBIA expression was negative in 16 of the 101 samples (15.8%). EGFR and K-ras mutations and EML4-ALK fusion were detected in 61 (60.5%), 1 (1.0%), and 2 (2.0%) of the 101 samples, respectively, in a completely mutually exclusive manner. Negative NFKBIA expression was observed significantly more frequently among the tumors with none of the three genetic alterations compared to those with such alterations (p＝0.009). In addition, negative NFKBIA expression was significantly more frequent among the EGFR-wild type samples compared to the EGFR-mutant samples (p＝0.013). In conclusion, NFKBIA expression was silenced in adenocarcinomas without EGFR/K-ras mutations or EML4-ALK fusion, suggesting that the silencing of NFKBIA may play an important role in the carcinogenesis of adenocarcinomas independent of EGFR/K-ras mutations or EML4-ALK fusion

Linking and causality in globally hyperbolic spacetimes

The linking number $lk$ is defined if link components are zero homologous. Our affine linking invariant $alk$ generalizes $lk$ to the case of linked submanifolds with arbitrary homology classes. We apply $alk$ to the study of causality in Lorentz manifolds. Let $M^m$ be a spacelike Cauchy surface in a globally hyperbolic spacetime $(X^{m+1}, g)$. The spherical cotangent bundle $ST^*M$ is identified with the space $N$ of all null geodesics in $(X,g).$ Hence the set of null geodesics passing through a point $x\in X$ gives an embedded $(m-1)$-sphere $S_x$ in $N=ST^*M$ called the sky of $x.$ Low observed that if the link $(S_x, S_y)$ is nontrivial, then $x,y\in X$ are causally related. This motivated the problem (communicated by Penrose) on the Arnold's 1998 problem list to apply link theory to the study of causality. The spheres $S_x$ are isotopic to fibers of $(ST^*M)^{2m-1}\to M^m.$ They are nonzero homologous and $lk(S_x,S_y)$ is undefined when $M$ is closed, while $alk(S_x, S_y)$ is well defined. Moreover, $alk(S_x, S_y)\in Z$ if $M$ is not an odd-dimensional rational homology sphere. We give a formula for the increment of \alk under passages through Arnold dangerous tangencies. If $(X,g)$ is such that $alk$ takes values in $\Z$ and $g$ is conformal to $g'$ having all the timelike sectional curvatures nonnegative, then $x, y\in X$ are causally related if and only if $alk(S_x,S_y)\neq 0$. We show that $x,y$ in nonrefocussing $(X, g)$ are causally unrelated iff $(S_x, S_y)$ can be deformed to a pair of $S^{m-1}$-fibers of $ST^*M\to M$ by an isotopy through skies. Low showed that if (\ss, g) is refocussing, then $M$ is compact. We show that the universal cover of $M$ is also compact.Comment: We added: Theorem 11.5 saying that a Cauchy surface in a refocussing space time has finite pi_1; changed Theorem 7.5 to be in terms of conformal classes of Lorentz metrics and did a few more changes. 45 pages, 3 figures. A part of the paper (several results of sections 4,5,6,9,10) is an extension and development of our work math.GT/0207219 in the context of Lorentzian geometry. The results of sections 7,8,11,12 and Appendix B are ne

A Case of Metastatic Atypical Neuroendocrine Tumor with ALK Translocation and Diffuse Brain Metastases.

A challenge in precision medicine requires identification of actionable driver mutations. Critical to such effort is the deployment of sensitive and well-validated assays for mutation detection. Although identification of such alterations within the tumor tissue remains the gold standard, many advanced non-small cell lung cancer cases have only limited tissue samples, derived from small biopsies or fine-needle aspirates, available for testing. More recently, noninvasive methods using either circulating tumor cells or tumor DNA (ctDNA) have become an alternative method for identifying molecular biomarkers and screening patients eligible for targeted therapies. In this article, we present a case of a 52-year-old never-smoking male who presented with widely metastatic atypical neuroendocrine tumor to the bones and the brain. Molecular genotyping using DNA harvested from a bone metastasis was unsuccessful due to limited material. Subsequent ctDNA analysis revealed an ALK translocation. The clinical significance of the mutation in this particular cancer type and therapeutic strategies are discussed.Key pointsTo our knowledge, this index case represents the first reported ALK translocation identified in an atypical carcinoid tumor.Liquid biopsy such as circulating tumor DNA is a feasible alternative platform for identifying sensitizing genomic alterations.Second-generation ALK inhibitors represent a new paradigm for treating ALK-positive patients with brain metastases

Successful role of adjuvant radiotherapy in a rare case of tracheal inflammatory myofibroblastic tumor: a case report

BACKGROUND:: Inflammatory myofibroblastic tumor (IMT) is a rare benign cancer that can express a more aggressive phenotype related to the genetic mutation of the anaplastic lymphoma kinase receptor (ALK). Involvement of trachea is extremely rare and due to the clinical and radiologic nonspecificity, the definitive diagnosis is based on the histologic evaluation of tissue specimens. Total surgical excision is curative and chemotherapy or radiotherapy has been employed in the treatment of unresectable tumors or as adjuvant therapies. CASE PRESENTATION:: The case described here is being reported because of the rare tracheal location and the atypical treatment approach used for an ALK-positive IMT. A 7-week pregnant woman voluntary interrupted pregnancy and underwent total surgical excision that resulted to have close margins. Although ALK-positive expression indicated the use of ALK inhibitors, she refused any type of adjuvant therapy that could affect ovarian function. Thus, 3D conformational external beam radiotherapy was performed with a daily dose of 180 cGy, 5 times per week, up to 45 Gy at the level of trachea. A total of 62 months of follow-up showed and no signs of disease recurrence or late radiation therapy-related toxicity. CONCLUSIONS: This report describes an extremely rare case of a tracheal IMT, underlying the key role of radiotherapy as adjuvant treatment able to definitively cure IMT, limiting systemic chemotherapy-related toxicity

Comparing the stromal demarcation line depth in standard versus high-intensity corneal CXL using anterior segment OCT

Paper no. 10466PURPOSE: To compare the depth of the corneal stromal demarcation line at center and periphery in standard versus high intensity collagen cross-linking (CXL) using Visante (Carl-Zeiss Meditec) anterior segment optical coherence tomography (AS-OCT). METHODS: Cases with keratoconus or post-LASIK ectasia with CXL performed by a single surgeon in a private setting tertiary hospital during a 24 month period (November 2011 to November 2013) were retrospectively reviewed. Cases were divided into Group 1: standard 30 minutes CXL with average intensity 3.0 mW/cm² and Group 2: high intensity 10 minutes ...postprin

Anaplastic lymphoma kinase (ALK) inhibitor response in neuroblastoma is highly correlated with ALK mutation status, ALK mRNA and protein levels

Background In pediatric neuroblastoma (NBL), high anaplastic lymphoma kinase (ALK) levels appear to be correlated with an unfavorable prognosis, regardless of ALK mutation status. This suggests a therapeutic role for ALK inhibitors in NBL patients. We examined the correlation between levels of ALK, phosphorylated ALK (pALK) and downstream signaling proteins and response to ALK inhibition in a large panel of both ALK mutated and wild type (WT) NBL cell lines. Methods We measured protein levels by western blot and ALK inhibitor sensitivity (TAE684) by viability assays in 19 NBL cell lines of which 6 had a point mutation and 4 an amplification of the ALK gene. Results ALK 220 kDa (p=0.01) and ALK 140 kDa (p= 0.03) protein levels were higher in ALK mutant than WT cell lines. Response to ALK inhibition was significantly correlated with ALK protein levels (p<0.01). ALK mutant cell lines (n=4) were 14,9 fold (p<0,01) more sensitive to ALK inhibition than eight WT cell lines. Conclusion NBL cell lines often express ALK at high levels and are responsive to ALK inhibitors. Mutated cell lines express ALK at higher levels, which may define their superior response to ALK inhibition