Showing papers by "Hiroyuki Mano published in 2012"

RET, ROS1 and ALK fusions in lung cancer.

Abstract: Through an integrated screening system, the authors catalog ALK and ROS1 fusions in lung cancer and identify a new class of fusions involving KIF5B and RET that may represent new therapeutic targets in adenocarcinoma.

A common BIM deletion polymorphism mediates intrinsic resistance and inferior responses to tyrosine kinase inhibitors in cancer.

Abstract: Tyrosine kinase inhibitors (TKIs) elicit high response rates among individuals with kinase-driven malignancies, including chronic myeloid leukemia (CML) and epidermal growth factor receptor-mutated non-small-cell lung cancer (EGFR NSCLC). However, the extent and duration of these responses are heterogeneous, suggesting the existence of genetic modifiers affecting an individual's response to TKIs. Using paired-end DNA sequencing, we discovered a common intronic deletion polymorphism in the gene encoding BCL2-like 11 (BIM). BIM is a pro-apoptotic member of the B-cell CLL/lymphoma 2 (BCL2) family of proteins, and its upregulation is required for TKIs to induce apoptosis in kinase-driven cancers. The polymorphism switched BIM splicing from exon 4 to exon 3, which resulted in expression of BIM isoforms lacking the pro-apoptotic BCL2-homology domain 3 (BH3). The polymorphism was sufficient to confer intrinsic TKI resistance in CML and EGFR NSCLC cell lines, but this resistance could be overcome with BH3-mimetic drugs. Notably, individuals with CML and EGFR NSCLC harboring the polymorphism experienced significantly inferior responses to TKIs than did individuals without the polymorphism (P = 0.02 for CML and P = 0.027 for EGFR NSCLC). Our results offer an explanation for the heterogeneity of TKI responses across individuals and suggest the possibility of personalizing therapy with BH3 mimetics to overcome BIM-polymorphism-associated TKI resistance.

KLC1-ALK: a novel fusion in lung cancer identified using a formalin-fixed paraffin-embedded tissue only.

Abstract: The promising results of anaplastic lymphoma kinase (ALK) inhibitors have changed the significance of ALK fusions in several types of cancer These fusions are no longer mere research targets or diagnostic markers, but they are now directly linked to the therapeutic benefit of patients However, most available tumor tissues in clinical settings are formalin-fixed and paraffin-embedded (FFPE), and this significantly limits detailed genetic studies in many clinical cases Although recent technical improvements have allowed the analysis of some known mutations in FFPE tissues, identifying unknown fusion genes by using only FFPE tissues remains difficult We developed a 5′-rapid amplification of cDNA ends-based system optimized for FFPE tissues and evaluated this system on a lung cancer tissue with ALK rearrangement and without the 2 known ALK fusions EML4-ALK and KIF5B-ALK With this system, we successfully identified a novel ALK fusion, KLC1-ALK The result was confirmed by reverse transcription-polymerase chain reaction and fluorescence in situ hybridization Then, we synthesized the putative full-length cDNA of KLC1-ALK and demonstrated the transforming potential of the fusion kinase with assays using mouse 3T3 cells To the best of our knowledge, KLC1-ALK is the first novel oncogenic fusion identified using only FFPE tissues This finding will broaden the potential value of archival FFPE tissues and provide further biological and clinical insights into ALK-positive lung cancer

ALKoma: A Cancer Subtype with a Shared Target

Abstract: Anaplastic lymphoma kinase (ALK) is a receptor-type protein tyrosine kinase that is currently the focus of much attention in oncology. ALK is rendered oncogenic as a result of its fusion to NPM1 in anaplastic large cell lymphoma, to TPM3 or TPM4 in inflammatory myofibroblastic tumor, to EML4 in non-small cell lung carcinoma, and to VCL in renal medullary carcinoma. It is also activated as a result of missense mutations in neuroblastoma and anaplastic thyroid cancer. Whereas these various tumors arise in different organs, they share activated ALK, and a marked clinical efficacy with ALK inhibitors has already been shown for some of the tumors with ALK fusions. One of such compound, crizotinib, is now approved in the United States for the treatment of lung cancer positive for ALK rearrangement. I propose that tumors carrying abnormal ALK as an essential growth driver be collectively termed "ALKoma."

Identification of Anaplastic Lymphoma Kinase Fusions in Renal Cancer Large-Scale Immunohistochemical Screening by the Intercalated Antibody-Enhanced Polymer Method

Abstract: BACKGROUND: Several promising molecular-targeted drugs are used for advanced renal cancers. However, complete remission is rarely achieved, because none of the drugs targets a key molecule that is specific to the cancer, or is associated with “oncogene addiction” (dependence on one or a few oncogenes for cell survival) of renal cancer. Recently, an anaplastic lymphoma kinase (ALK) fusion, vinculin-ALK, has been reported in pediatric renal cell carcinoma (RCC) cases who have a history of sickle cell trait. In this context, ALK inhibitor therapy would constitute a therapeutic advance, as has previously been demonstrated with lung cancer, inflammatory myofibroblastic tumors, and anaplastic large cell lymphomas. METHODS: Anti-ALK immunohistochemistry was used to screen 355 tumor tissues, using the intercalated antibody-enhanced polymer (iAEP) method. The cohort consisted of 255 clear cell RCCs, 32 papillary RCCs, 34 chromophobe RCCs, 6 collecting duct carcinomas, 10 unclassified RCCs, 6 sarcomatoid RCCs, and 12 other tumors. RESULTS: Two patients (36- and 53-year-old females) were positive for ALK as determined by iAEP immunohistochemistry. Using 5′- rapid amplification of complementary DNA ends, we detected TPM3-ALK and EML4-ALK in these tumors. The results of this study were confirmed by fluorescence in situ hybridization assays. The 2 ALK-positive RCCs were unclassified (mixed features of papillary, mucinous cribriform, and solid patterns with rhabdoid cells) and papillary subtype. They comprised 2.3% of non–clear cell RCCs (2 of 88) and 3.7% of non–clear cell and nonchromophobe RCCs (2 of 54). CONCLUSIONS: The results of this study indicate that ALK fusions also exist in adult RCC cases without uncommon backgrounds. These findings confirm the potential of ALK inhibitor therapy for selected cases of RCC. Cancer 2012. © 2012 American Cancer Society.

A prospective PCR-based screening for the EML4-ALK oncogene in non-small cell lung cancer.

Abstract: Purpose: EML4-ALK is a lung cancer oncogene, and ALK inhibitors show marked therapeutic efficacy for tumors harboring this fusion gene. It remains unsettled, however, how the fusion gene should be detected in specimens other than formalin-fixed, paraffin-embedded tissue. We here tested whether reverse transcription PCR (RT-PCR)-based detection of EML4-ALK is a sensitive and reliable approach. Experimental Design: We developed a multiplex RT-PCR system to capture ALK fusion transcripts and applied this technique to our prospective, nationwide cohort of non–small cell lung cancer (NSCLC) in Japan. Results: During February to December 2009, we collected 916 specimens from 853 patients, quality filtering of which yielded 808 specimens of primary NSCLC from 754 individuals. Screening for EML4-ALK and KIF5B-ALK with our RT-PCR system identified EML4-ALK transcripts in 36 samples (4.46%) from 32 individuals (4.24%). The RT-PCR products were detected in specimens including bronchial washing fluid ( n = 11), tumor biopsy ( n = 8), resected tumor ( n = 7), pleural effusion ( n = 5), sputum ( n = 4), and metastatic lymph node ( n = 1). The results of RT-PCR were concordant with those of sensitive immunohistochemistry with ALK antibodies. Conclusions: Multiplex RT-PCR was confirmed to be a reliable technique for detection of ALK fusion transcripts. We propose that diagnostic tools for EML4-ALK should be selected in a manner dependent on the available specimen types. FISH and sensitive immunohistochemistry should be applied to formalin-fixed, paraffin-embedded tissue, but multiplex RT-PCR is appropriate for other specimen types. Clin Cancer Res; 18(20); 5682–9. ©2012 AACR .

Paracrine Receptor Activation by Microenvironment Triggers Bypass Survival Signals and ALK Inhibitor Resistance in EML4-ALK Lung Cancer Cells

Abstract: Purpose: Cancer cell microenvironments, including host cells, can critically affect cancer cell behaviors, including drug sensitivity. Although crizotinib, a dual tyrosine kinase inhibitor (TKI) of ALK and Met, shows dramatic effect against EML4-ALK lung cancer cells, these cells can acquire resistance to crizotinib by several mechanisms, including ALK amplification and gatekeeper mutation. We determined whether microenvironmental factors trigger ALK inhibitor resistance in EML4-ALK lung cancer cells. Experimental Design: We tested the effects of ligands produced by endothelial cells and fibroblasts, and the cells themselves, on the susceptibility of EML4-ALK lung cancer cell lines to crizotinib and TAE684, a selective ALK inhibitor active against cells with ALK amplification and gatekeeper mutations, both in vitro and in vivo . Results: EML4-ALK lung cancer cells were highly sensitive to ALK inhibitors. EGF receptor (EGFR) ligands, such as EGF, TGF-α, and HB-EGF, activated EGFR and triggered resistance to crizotinib and TAE684 by transducing bypass survival signaling through Erk1/2 and Akt. Hepatocyte growth factor (HGF) activated Met/Gab1 and triggered resistance to TAE684, but not crizotinib, which inhibits Met. Endothelial cells and fibroblasts, which produce the EGFR ligands and HGF, respectively, decreased the sensitivity of EML4-ALK lung cancer cells to crizotinib and TAE684, respectively. EGFR-TKIs resensitized these cells to crizotinib and Met-TKI to TAE684 even in the presence of EGFR ligands and HGF, respectively. Conclusions: Paracrine receptor activation by ligands from the microenvironment may trigger resistance to ALK inhibitors in EML4-ALK lung cancer cells, suggesting that receptor ligands from microenvironment may be additional targets during treatment with ALK inhibitors. Clin Cancer Res; 18(13); 3592–602. ©2012 AACR .

Oncogenic MAP2K1 mutations in human epithelial tumors

Abstract: The scirrhous subtype of gastric cancer is a highly infiltrative tumor with a poor outcome. To identify a transforming gene in this intractable disorder, we constructed a retroviral complementary DNA (cDNA) expression library from a cell line (OCUM-1) of scirrhous gastric cancer. A focus formation assay with the library and mouse 3T3 fibroblasts led to the discovery of a transforming cDNA, encoding for MAP2K1 with a glutamine-to-proline substitution at amino acid position 56. Interestingly, treatment with a MAP2K1-specific inhibitor clearly induced cell death of OCUM-1 but not of other two cells lines of scirrhous gastric cancer that do not carry MAP2K1 mutations, revealing the essential role of MAP2K1(Q56P) in the transformation mechanism of OCUM-1 cells. By using a next-generation sequencer, we further conducted deep sequencing of the MAP2K1 cDNA among 171 human cancer specimens or cell lines, resulting in the identification of one known (D67N) and four novel (R47Q, R49L, I204T and P306H) mutations within MAP2K1. The latter four changes were further shown to confer transforming potential to MAP2K1. In our experiments, a total of six (3.5%) activating mutations in MAP2K1 were thus identified among 172 of specimens or cell lines for human epithelial tumors. Given the addiction of cancer cells to the elevated MAP2K1 activity for proliferation, human cancers with such MAP2K1 mutations are suitable targets for the treatment with MAP2K1 inhibitors.

Ex vivo expansion of human CD8 + T cells using autologous CD4 + T cell help

Abstract: Background Using in vivo mouse models, the mechanisms of CD4+ T cell help have been intensively investigated. However, a mechanistic analysis of human CD4+ T cell help is largely lacking. Our goal was to elucidate the mechanisms of human CD4+ T cell help of CD8+ T cell proliferation using a novel in vitro model. Methods/Principal Findings We developed a genetically engineered novel human cell-based artificial APC, aAPC/mOKT3, which expresses a membranous form of the anti-CD3 monoclonal antibody OKT3 as well as other immune accessory molecules. Without requiring the addition of allogeneic feeder cells, aAPC/mOKT3 enabled the expansion of both peripheral and tumor-infiltrating T cells, regardless of HLA-restriction. Stimulation with aAPC/mOKT3 did not expand Foxp3+ regulatory T cells, and expanded tumor infiltrating lymphocytes predominantly secreted Th1-type cytokines, interferon-γ and IL-2. In this aAPC-based system, the presence of autologous CD4+ T cells was associated with significantly improved CD8+ T cell expansion in vitro. The CD4+ T cell derived cytokines IL-2 and IL-21 were necessary but not sufficient for this effect. However, CD4+ T cell help of CD8+ T cell proliferation was partially recapitulated by both adding IL-2/IL-21 and by upregulation of IL-21 receptor on CD8+ T cells. Conclusions We have developed an in vitro model that advances our understanding of the immunobiology of human CD4+ T cell help of CD8+ T cells. Our data suggests that human CD4+ T cell help can be leveraged to expand CD8+ T cells in vitro.

High-throughput resequencing of target-captured cDNA in cancer cells.

Abstract: The recent advent of whole exon (exome)-capture technology, coupled with second-generation sequencers, has made it possible to readily detect genomic alterations that affect encoded proteins in cancer cells. Such target resequencing of the cancer genome, however, fails to detect most clinically-relevant gene fusions, given that such oncogenic fusion genes are often generated through intron-to-intron ligation. To develop a resequencing platform that simultaneously captures point mutations, insertions-deletions (indels), and gene fusions in the cancer genome, we chose cDNA as the input for target capture and extensive resequencing, and we describe the versatility of such a cDNA-capture system. As a test case, we constructed a custom target-capture system for 913 cancer-related genes, and we purified cDNA fragments for the target gene set from five cell lines of CML. Our target gene set included Abelson murine leukemia viral oncogene homolog 1 (ABL1), but it did not include breakpoint cluster region (BCR); however, the sequence output faithfully detected reads spanning the fusion points of these two genes in all cell lines, confirming the ability of cDNA capture to detect gene fusions. Furthermore, computational analysis of the sequence dataset successfully identified non-synonymous mutations and indels, including those of tumor protein p53 (TP53). Our data might thus support the feasibility of a cDNA-capture system coupled with massively parallel sequencing as a simple platform for the detection of a variety of anomalies in protein-coding genes among hundreds of cancer specimens.