Seiji Yano

Kanazawa University, Kanazawa, Ishikawa, Japan

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Publications (191)658.73 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Akt kinase-interacting protein 1 (Aki1) has been reported to be a scaffold protein of the PI3K (phosphoinositide 3-kinase)/PDK1 (3-phosphoinositide-dependent protein kinase)/Akt pathway and to interact with epidermal growth factor receptor signaling. Although Aki1 has been reported to be expressed in lung cancer, the significance of its expression in pancreatic cancer has not been clarified.
    Pancreas 07/2014; · 2.95 Impact Factor
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    ABSTRACT: Alectinib is a new generation ALK inhibitor with activity against the gatekeeper L1196M mutation that showed remarkable activity in a phase I/II study with echinoderm microtubule associated protein-like 4 (EML4) - anaplastic lymphoma kinase (ALK) non-small cell lung cancer (NSCLC) patients. However, alectinib resistance may eventually develop. Here, we found that EGFR ligands and HGF, a ligand of the MET receptor, activate EGFR and MET, respectively, as alternative pathways, and thereby induce resistance to alectinib. Additionally, the heat shock protein 90 (Hsp90) inhibitor suppressed protein expression of ALK, MET, EGFR, and AKT, and thereby induced apoptosis in EML4-ALK NSCLC cells, even in the presence of EGFR ligands or HGF. These results suggest that Hsp90 inhibitors may overcome ligand-triggered resistance to new generation ALK inhibitors and may result in more successful treatment of NSCLC patients with EML4-ALK.
    Oncotarget 06/2014; · 6.64 Impact Factor
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    ABSTRACT: Met activation by gene amplification and its ligand, hepatocyte growth factor (HGF), imparts resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) in EGFR-mutant lung cancer. We recently reported that Met activation by HGF stimulates the production of vascular endothelial growth factor (VEGF) and facilitates angiogenesis, which indicates that HGF induces EGFR-TKI resistance and angiogenesis. This study aimed to determine the effect of triple inhibition of EGFR, Met, and angiogenesis on HGF-triggered EGFR-TKI resistance in EGFR-mutant lung cancer. Three clinically approved drugs, erlotinib (an EGFR inhibitor), crizotinib (an inhibitor of anaplastic lymphoma kinase and Met), and bevacizumab (anti-VEGF antibody), and TAS-115, a novel dual TKI for Met and VEGF receptor 2, were used in this study. EGFR-mutant lung cancer cell lines PC-9, HCC827, and HGF-gene-transfected PC-9 (PC-9/HGF) cells were examined. Crizotinib and TAS-115 inhibited Met phosphorylation and reversed erlotinib resistance and VEGF production triggered by HGF in PC-9 and HCC827 cells in vitro. Bevacizumab and TAS-115 inhibited angiogenesis in PC-9/HGF tumors in vivo. Moreover, the triplet erlotinib, crizotinib, and bevacizumab, or the doublet erlotinib and TAS-115 successfully inhibited PC-9/HGF tumor growth and delayed tumor regrowth associated with sustained tumor vasculature inhibition even after cessation of the treatment. These results suggest that triple inhibition of EGFR, HGF/Met, and VEGF/VEGF receptor 2, by either a triplet of clinical drugs or TAS-115 combined with erlotinib, may be useful for controlling progression of EGFR-mutant lung cancer by reversing EGFR-TKI resistance and for inhibiting angiogenesis.
    Journal of thoracic oncology: official publication of the International Association for the Study of Lung Cancer 06/2014; 9(6):775-83. · 4.55 Impact Factor
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    ABSTRACT: Mutations in Kirsten rat-sarcoma (KRAS) are well appreciated to be major drivers of human cancers through dysregulation of multiple growth and survival pathways. Similar to many other non-kinase oncogenes and tumor suppressors, efforts to directly target KRAS pharmaceutically have not yet materialized. As a result, there is broad interest in an alternative approach to develop therapies that induce synthetic lethality in cancers with mutant KRAS, therefore exposing the particular vulnerabilities of these cancers. Fueling these efforts is our increased understanding into the biology driving KRAS mutant cancers, in particular the important pathways that mutant KRAS governs to promote survival. In this mini-review, we summarize the latest approaches to treat KRAS mutant cancers and the rationale behind them. This article is protected by copyright. All rights reserved.
    Cancer Science 02/2014; · 3.48 Impact Factor
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    ABSTRACT: The mTOR inhibitor temsirolimus has antitumor and antiangiogenic activity against several carcinomas, yet few reports document the efficacy of temsirolimus against malignant pleural mesothelioma (MPM). Therefore, we evaluated the efficacy of temsirolimus and the antiangiogenic effect of temsirolimus in the treatment of MPM. We examined the efficacy of temsirolimus alone and the efficacy of the combination of temsirolimus and cisplatin or pemetrexed against four MPM cell lines using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. The effect of temsirolimus on the production of proangiogenic cytokines by MPM cell lines was examined by enzyme-linked immunosorbent assay (ELISA). Expression of mTOR and proangiogenic cytokines in clinical specimens from MPM patients was determined by immunohistochemistry. Temsirolimus inhibited cell viability and suppressed cell proliferation of all MPM cell lines. Combined treatment with temsirolimus and cisplatin inhibited the viability of all MPM cell lines more effectively than temsirolimus alone. Temsirolimus strongly inhibited the phosphorylation of p70s6k, a downstream molecule of mTOR, in all MPM cell lines and led to an increase in the levels of cleaved caspase-3 in the H226 and Y-meso14 cells. Temsirolimus also inhibited the production of vascular endothelial growth factor (VEGF) and platelet-derived growth factor-AA (PDGF-AA). Phosphorylated mTOR and high expression of VEGF and PDGF were detected in 2 and 3, respectively, out of the 5 MPM specimens. These results suggest that temsirolimus has activity against MPM cells by inhibition of cell proliferation and angiogenesis, and may be beneficial for a subset of MPM patients with high mTOR expression.
    Oncology Reports 12/2013; · 2.30 Impact Factor
  • Seiji Yano, Takayuki Nakagawa
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    ABSTRACT: Met is a tyrosine kinase that has hepatocyte growth factor as its ligand. Met plays a major role in cell growth, migration and morphological changes. Overexpression of hepatocyte growth factor and Met and mutations and amplification of MET have been noted in many forms of cancer and are reportedly correlated with cancer progression and a poor prognosis. Over the past few years, these molecules have attracted attention as targets of molecularly targeted therapies. This article describes the association relationship between hepatocyte growth factor/Met and cancer and it describes the latest findings regarding inhibitors to target hepatocyte growth factor/Met that are currently being developed.
    Japanese Journal of Clinical Oncology 12/2013; · 1.90 Impact Factor
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    ABSTRACT: The PI3K pathway is genetically altered in excess of 70% of breast cancers, largely through PIK3CA mutation and HER2 amplification. Preclinical studies have suggested that these subsets of breast cancers are particularly sensitive to PI3K inhibitors; however, the reasons for this heightened sensitivity are mainly unknown. We investigated the signaling effects of PI3K inhibition in PIK3CA mutant and HER2 amplified breast cancers using PI3K inhibitors currently in clinical trials. Unexpectedly, we found that in PIK3CA mutant and HER2 amplified breast cancers sensitive to PI3K inhibitors, PI3K inhibition led to a rapid suppression of Rac1/p21-activated kinase (PAK)/protein kinase C-RAF (C-RAF)/ protein kinase MEK (MEK)/ERK signaling that did not involve RAS. Furthermore, PI3K inhibition led to an ERK-dependent up-regulation of the proapoptotic protein, BIM, followed by induction of apoptosis. Expression of a constitutively active form of Rac1 in these breast cancer models blocked PI3Ki-induced down-regulation of ERK phosphorylation, apoptosis, and mitigated PI3K inhibitor sensitivity in vivo. In contrast, protein kinase AKT inhibitors failed to block MEK/ERK signaling, did not up-regulate BIM, and failed to induce apoptosis. Finally, we identified phosphatidylinositol 3,4,5-trisphosphate-dependent Rac exchanger 1 (P-Rex1) as the PI(3,4,5)P3-dependent guanine exchange factor for Rac1 responsible for regulation of the Rac1/C-RAF/MEK/ERK pathway in these cells. The expression level of P-Rex1 correlates with sensitivity to PI3K inhibitors in these breast cancer cell lines. Thus, PI3K inhibitors have enhanced activity in PIK3CA mutant and HER2 amplified breast cancers in which PI3K inhibition down-regulates both the AKT and Rac1/ERK pathways. In addition, P-Rex1 may serve as a biomarker to predict response to single-agent PI3K inhibitors within this subset of breast cancers.
    Proceedings of the National Academy of Sciences 12/2013; · 9.81 Impact Factor
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    ABSTRACT: Scirrhous gastric cancer is associated with abundant stroma and frequently develops into peritoneal carcinomatosis with malignant ascites. Although malignant ascites is among the most deadly diseases worldwide, its molecular pathogenesis is poorly understood. We investigated the role of hepatocyte growth factor (HGF) in the production of peritoneal carcinomatosis with malignant ascites. We examined 3 scirrhous and 3 non-scirrhous human gastric cancer cell lines for the production of peritoneal carcinomatosis in vivo and responses to HGF in vitro. Furthermore, clinical scirrhous gastric cancer specimens were examined for HGF production. Among the 6 cell lines examined, only 2 scirrhous cell lines (NUGC4 and GCIY) produced peritoneal carcinomatosis with massive ascites after intraperitoneal injection in nude mice. Their proliferation was stimulated by exogenous HGF in vitro. On the other hand, a non-scirrhous cell line, MKN45, with MET amplification generated peritoneal tumors but not ascites. MET tyrosine kinase inhibitors, crizotinib and TAS-115, inhibited HGF-stimulated proliferation of NUGC4 and GCIY as well as constitutive proliferation of MKN45. Furthermore, crizotinib and TAS-115 prolonged the survival of mice bearing established tumors by NUGC4 or MKN45. In clinical specimens, HGF was markedly produced by stromal fibroblasts. Malignant ascitic fluids from patients with peritoneal carcinomatosis contained high levels of HGF. Our results strongly suggest that paracrine HGF-induced activation of MET-mediated signaling pathways plays an important role in the pathogenesis of peritoneal carcinomatosis in scirrhous gastric cancer. Thus, MET signaling pathway may be a potential therapeutic target for peritoneal carcinomatosis of gastric cancer, even without MET amplification. This article is protected by copyright. All rights reserved.
    Cancer Science 10/2013; · 3.48 Impact Factor
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    ABSTRACT: Acquired resistance to epidermal growth factor receptor–tyrosine kinase inhibitors (EGFR–TKIs), such as gefitinib and erlotinib, is a critical problem in the management of patients with EGFR mutant lung cancer. Several mechanisms have been reported involved in this acquired resistance, including hepatocyte growth factor (HGF) activation of an alternative pathway. PI3K and mTOR are downstream molecules of receptor tyrosine kinases, such as EGFR and Met, and are thought to be ideal targets for controlling various tumor types. We assessed whether BEZ235, a dual inhibitor of PI3K and mTOR, could overcome the EGFR–TKI resistance induced by HGF in an EGFR mutant lung cancer model. Exogenous and endogenous HGF triggered resistance to erlotinib in the PC-9 and HCC827, EGFR mutant lung cancer cell lines. BEZ235 alone inhibited the viability of PC-9 and HCC827 cells in vitro, irrespective of the presence or the absence of HGF. Using a xenograft model of severe combined immunodeficient mice with HGF-gene-transfected PC-9 cells (PC-9/HGF), we found that BEZ235 inhibited tumor growth, whereas erlotinib did not. BEZ235 monotherapy also inhibited the phosphorylation of Akt and p70S6K/S6RP, downstream molecules of PI3K and mTOR, respectively, as well as suppressing tumor-cell proliferation and angiogenesis of PC-9/HGF tumors. These results suggest that BEZ235, even as monotherapy, may be useful in managing HGF-induced EGFR–TKI resistance in EGFR mutant lung cancer.
    International Journal of Cancer 07/2013; 133(2). · 6.20 Impact Factor
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    ABSTRACT: Podoplanin (Aggrus), which is a type I transmembrane sialomucin-like glycoprotein, is highly expressed in malignant pleural mesothelioma (MPM). We previously reported the generation of a rat anti-human podoplanin Ab, NZ-1, which inhibited podoplanin-induced platelet aggregation and hematogenous metastasis. In this study, we examined the antitumor effector functions of NZ-1 and NZ-8, a novel rat-human chimeric Ab generated from NZ-1 including Ab-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity against MPM in vitro and in vivo. Immunostaining with NZ-1 showed the expression of podoplanin in 73% (11 out of 15) of MPM cell lines and 92% (33 out of 36) of malignant mesothelioma tissues. NZ-1 could induce potent ADCC against podoplanin-positive MPM cells mediated by rat NK (CD161a(+)) cells, but not murine splenocytes or human mononuclear cells. Treatment with NZ-1 significantly reduced the growth of s.c. established tumors of MPM cells (ACC-MESO-4 or podoplanin-transfected MSTO-211H) in SCID mice, only when NZ-1 was administered with rat NK cells. In in vivo imaging, NZ-1 efficiently accumulated to xenograft of MPM, and its accumulation continued for 3 wk after systemic administration. Furthermore, NZ-8 preferentially recognized podoplanin expressing in MPM, but not in normal tissues. NZ-8 could induce higher ADCC mediated by human NK cells and complement-dependent cytotoxicity as compared with NZ-1. Treatment with NZ-8 and human NK cells significantly inhibited the growth of MPM cells in vivo. These results strongly suggest that targeting therapy to podoplanin with therapeutic Abs (i.e., NZ-8) derived from NZ-1 might be useful as a novel immunotherapy against MPM.
    The Journal of Immunology 05/2013; · 5.52 Impact Factor
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    ABSTRACT: Surfactant protein A (SP-A) is a large multimeric protein found in the lungs. In addition to its immunoregulatory function in infectious respiratory diseases, SP-A is also used as a marker of lung adenocarcinoma. Despite the finding that SP-A expression levels in cancer cells has a relationship with patient prognosis, the function of SP-A in lung cancer progression is unknown. We investigated the role of SP-A in lung cancer progression by introducing the SP-A gene into human lung adenocarcinoma cell lines. SP-A gene transduction suppressed the progression of tumor in subcutaneous xenograft or lung metastasis mouse models. Immunohistochemical analysis showed that the number of M1 antitumor tumor-associated macrophages (TAMs) was increased and the number of M2 tumor-promoting TAMs was not changed in the tumor tissue produced by SP-A-expressing cells. In addition, natural killer (NK) cells were also increased and activated in the SP-A-expressing tumor. Moreover, SP-A did not inhibit tumor progression in mice depleted of NK cells. Taking into account that SP-A did not directly activate NK cells, these results suggest that SP-A inhibited lung cancer progression by recruiting and activating NK cells via controlling the polarization of TAMs.
    American Journal Of Pathology 03/2013; · 4.60 Impact Factor
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    ABSTRACT: BIM (BCL2L11) is a BH3-only pro-apoptotic member of the Bcl-2 protein family. BIM upregulation is required for apoptosis induction by EGFR tyrosine kinase inhibitors (EGFR-TKIs) in EGFR-mutant forms of non-small cell lung cancer (NSCLC). Notably, a BIM deletion polymorphism occurs naturally in 12.9% of East Asian individuals, impairing the generation of the pro-apoptotic isoform required for the EGFR-TKIs gefitinib and erlotinib and therefore conferring an inherent drug resistant phenotype. Indeed, NSCLC patients who harbored this host BIM polymorphism exhibited significantly inferior responses to EGFR-TKI treatment than individuals lacking this polymorphism. In attempt to correct this response defect in the resistant group, we investigated whether the histone deacetylase (HDAC) inhibitor vorinostat could circumvent EGFR-TKI resistance in EGFR mutant NSCLC cell lines that also harbored the BIM polymorphism. Consistent with our clinical observations, we found that such cells were much less sensitive to gefitinib-induced apoptosis than EGFR mutant cells which did not harbor the polymorphism. Notably, vorinostat increased expression in a dose-dependent manner of the pro-apoptotic BH3 domain-containing isoform of BIM, which was sufficient to restore gefitinib death sensitivity in the EGFR mutant, EGFR-TKI resistant cells. In xenograft models, while gefitinib induced marked regression, via apoptosis, of tumors without the BIM polymorphism, its combination with vorinostat was needed to induce marked regression of tumors with the BIM polymorphism in the same manner. Together, our results show how HDAC inhibition can epigenetically restore BIM function and death sensitivity of EGFR-TKI, in cases of EGFR mutant NSCLC where resistance to EGFR-TKI is associated with a common BIM polymorphism.
    Cancer Research 02/2013; · 9.28 Impact Factor
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    ABSTRACT: We report a case of a female in her 80s who was diagnosed with recurrent lung adenocarcinoma after primary surgery. She was treated with a systemic chemotherapy regimen consisting of carboplatin plus paclitaxel until the disease showed progression. On detection of epidermal growth factor receptor(EGFR)mutations, we administered gefitinib, an EGFR tyrosine kinase inhibitor, at a dosage of 250 mg daily. After 6 months of gefitinib therapy, laboratory findings revealed elevated serum aspartate aminotransferase(AST)and alanine aminotransferase(ALT)levels(grade 2), indicative of hepatotoxicity. Gefitinib was discontinued and erlotinib was initiated at a dosage of 50 mg daily. She continued the therapy for 3 years, during which her disease stabilized without any further complications or hepatotoxicity. Thus, low-dose erlotinib may be effective and well tolerated by patients with non-small cell lung cancer harboring EGFR mutations who are intolerant to gefitinib.
    Gan to kagaku ryoho. Cancer & chemotherapy 01/2013; 40(1):79-81.
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    ABSTRACT: Pancreatic cancer is frequently complicated by malignancies in other organs. However, synchronous triple cancers including pancreatic cancer have been seldom reported in the English language literature. We describe the rare case of a 77-year-old man with triple cancers of the pancreas, stomach, and cecum. Biopsies revealed that all three tumors were adenocarcinomas. The pancreatic and gastric tumors were positive for cytokeratin 7 and negative for cytokeratin 20, whereas the cecal tumor was negative for cytokeratin 7 and positive for cytokeratin 20. K-ras mutations were present at codon 12 in the pancreatic tumor and at codon 13 in the cecal tumor, but were absent from the gastric tumor. Since the three tumors had different characteristics, the patient was diagnosed with synchronous triple cancers. Because invasive surgery was required to remove all three tumors and the patient had risk factors for surgery, we elected to treat him with chemotherapy. All three cancers were markedly reduced in size by treatment with cycles of 100 mg/day S-1 for 2 weeks, followed by a 1-week rest. The patient later developed hypoproteinemia and anasarca, which was diagnosed as pancreatic exocrine insufficiency due to pancreatic head cancer. Treatment with pancrelipase resulted in dramatic improvements in hypoproteinemia and anasarca. This is the first case report in which S-1 was effective in triple cancers of the pancreas, stomach, and cecum. Patients with pancreatic head cancer should be monitored for pancreatic exocrine insufficiency.
    JOP: Journal of the pancreas 01/2013; 14(5):515-20.
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    ABSTRACT: Resistance to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs), gefitinib and erlotinib, is a critical problem in the treatment of EGFR mutant lung cancer. Several mechanisms, including bypass signaling by hepatocyte growth factor (HGF)-triggered Met activation, are implicated as mediators of resistance. The mammalian target of rapamycin (mTOR), is a downstream conduit of EGFR and MET signaling, and is thus considered a therapeutically attractive target in the treatment of various types of cancers. The purpose of this study was to examine whether 2 clinically approved mTOR inhibitors, temsirolimus and everolimus, overcome HGF-dependent resistance to EGFR-TKIs in EGFR mutant lung cancer cells. Both temsirolimus and everolimus inhibited the phosphorylation of p70S6K and 4E-BP1, which are downstream targets of the mTOR pathway, and reduced the viability of EGFR mutant lung cancer cells, PC-9, and HCC827, even in the presence of HGF in vitro. In a xenograft model, temsirolimus suppressed the growth of PC-9 cells overexpressing the HGF-gene; this was associated with suppression of the mTOR signaling pathway and tumor angiogenesis. In contrast, erlotinib did not suppress this signaling pathway or tumor growth. Multiple mechanisms, including the inhibition of vascular endothelial growth factor production by tumor cells and suppression of endothelial cell viability, contribute to the anti-angiogenic effect of temsirolimus. These findings indicate that mTOR inhibitors may be useful for controlling HGF-triggered EGFR-TKI resistance in EGFR mutant lung cancer, and they provide the rationale for clinical trials of mTOR inhibitors in patients stratified by EGFR mutation and HGF expression status.
    PLoS ONE 01/2013; 8(5):e62104. · 3.53 Impact Factor
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    ABSTRACT: Although EGF receptor tyrosine kinase inhibitors (EGFR-TKI) have shown dramatic effects against EGFR mutant lung cancer, patients ultimately develop resistance by multiple mechanisms. We therefore assessed the ability of combined treatment with the Met inhibitor crizotinib and new generation EGFR-TKIs to overcome resistance to first-generation EGFR-TKIs. Lung cancer cell lines made resistant to EGFR-TKIs by the gatekeeper EGFR-T790M mutation, Met amplification, and HGF overexpression and mice with tumors induced by these cells were treated with crizotinib and a new generation EGFR-TKI. The new generation EGFR-TKI inhibited the growth of lung cancer cells containing the gatekeeper EGFR-T790M mutation, but did not inhibit the growth of cells with Met amplification or HGF overexpression. In contrast, combined therapy with crizotinib plus afatinib or WZ4002 was effective against all three types of cells, inhibiting EGFR and Met phosphorylation and their downstream molecules. Crizotinib combined with afatinib or WZ4002 potently inhibited the growth of mouse tumors induced by these lung cancer cell lines. However, the combination of high dose crizotinib and afatinib, but not WZ4002, triggered severe adverse events. Our results suggest that the dual blockade of mutant EGFR and Met by crizotinib and a new generation EGFR-TKI may be promising for overcoming resistance to reversible EGFR-TKIs but careful assessment is warranted clinically.
    PLoS ONE 01/2013; 8(12):e84700. · 3.53 Impact Factor
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    ABSTRACT: Despite initial dramatic response, epidermal growth factor receptor (EGFR) mutant lung cancer patients always acquire resistance to EGFR-tyrosine kinase inhibitors (TKIs). Gatekeeper T790M mutation in EGFR is the most prevalent genetic alteration underlying acquired resistance to EGFR-TKI, and EGFR mutant lung cancer cells are reported to be addictive to EGFR/Akt signaling even after acquired T790M mutation. Here, we focused on Akt kinase-interacting protein1 (Aki1), a scaffold protein of PI3K (phosphoinositide 3-kinase)/PDK1 (3-phosphoinositide-dependent protein kinase)/Akt that determines receptor signal selectivity for non-mutated EGFR, and assessed its role in EGFR mutant lung cancer with or without gatekeeper T790M mutation. Cell line-based assays showed that Aki1 constitutively associates with mutant EGFR in lung cancer cells with (H1975) or without (PC-9 and HCC827) T790M gatekeeper mutation. Silencing of Aki1 induced apoptosis of EGFR mutant lung cancer cells. Treatment with Aki1 siRNA dramatically inhibited growth of H1975 cells in a xenograft model. Moreover, silencing of Aki1 further potentiated growth inhibitory effect of new generation EGFR-TKIs against H1975 cells in vitro. Aki1 was frequently expressed in tumor cells of EGFR mutant lung cancer patients (53/56 cases), including those with acquired resistance to EGFR-TKI treatment (7/7 cases). Our data suggest that Aki1 may be a critical mediator of survival signaling from mutant EGFR to Akt, and may therefore be an ideal target for EGFR mutant lung cancer patients, especially those with acquired EGFR-TKI resistance due to EGFR T790M gatekeeper mutation.Oncogene advance online publication, 8 October 2012; doi:10.1038/onc.2012.446.
    Oncogene 10/2012; · 8.56 Impact Factor
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    ABSTRACT: Most patients with lung cancer experience relapse, although epidermal growth factor receptor (EGFR) of tyrosine kinase inhibitor (TKI) has an astounding effect on tumors with EGFR-activating mutations. It is therefore critical to determine the mechanisms of resistance against agents and the prognostic value of acquired resistance-related molecules to EGFR-TKI. Tumor specimens were obtained from 19 matched specimens before and after treatment with gefitinib. A retrospective multi-institutional study analyzed the correlation between patients' survival and acquired resistance-related molecules in non-small cell lung cancer (NSCLC) samples, that possessed sensitive EGFR mutations (7 cases: exon 19 deletion, and 12 cases: exon 21 point mutation). The status of the epidermal growth factor receptor (EGFR) and KRAS genes were investigated by polymerase chain reaction (PCR)-based analyses. Real-time PCR assays were also used to evaluate MET gene amplification. The expression of hepatocyte growth factor (HGF) and changes in the epithelial-mesenchymal transition (EMT) status including the expression of E-cadherin and γ-catenin as epithelial markers, and those of vimentin and fibronectin as mesenchymal markers, were evaluated by immunohistochemistry. Eight of the gefitinib refractory tumors exhibited a secondary threonine-to-methionine mutation at codon 790 in EGFR (T790M). All of the tumors had wild type KRAS gene expression. No MET amplification was detected in any of the samples. A strong expression of HGF was detected in eight of the specimens at post-treatment. A change in the EMT status between pre-and post-treatment was found in five cases. The 5-year survival rate of patients with and without T790M was 86.7% and 13.3%, respectively (p=0.020). The 5-year overall survival (OS) rate for patients with overexpresion and for those with weak expression of HGF was 75.0% and 22.2%, respectively (p=0.259). In addition, the 5-year OS rate for patients with unchanged and changed EMT status was 83.3% and 40.0%, respectively (p=0.123). The current results showed that the presence of T790M is associated with favorable survival. On the other hand, the patients with weak HGF expression and EMT change tend to have a poor survival. The current patients' selection might be changed by discrimination of acquired resistance-related molecules in patients with NSCLC treated with an EGFR-TKI.
    Anticancer research 09/2012; 32(9):3785-90. · 1.71 Impact Factor
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    ABSTRACT: A 74-year-old woman diagnosed with poorly-differentiated neuroendocrine carcinoma originating from the ascending colon was referred to our hospital. She had felt anorexia, abdominal pains and her (ECOG) performance status was 3. Her CT scan showed that some abdominal lymph nodes were swelling and that there were many metastatic lesions occupying most of the liver. We started chemotherapy with cisplatin and irinotecan according to a regimen for small cell lung cancer. Considering her poor PS, both of the drugs were administered at 30mg/m² twice 4 weeks in the first course of chemotherapy. Her anorexia and abdominal pains immediately disappeared, and CT scan showed that all of the metastases were decreased in size. After 4 courses, however, some of the metastatic lesions were increased in size. She died 8 months after diagnosis. The tumor marker doubling time was 17 days.
    Gan to kagaku ryoho. Cancer & chemotherapy 09/2012; 39(9):1427-30.
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    ABSTRACT: We report a 53-year-old man with cancer of an unknown primary site with an epidermal growth factor receptor mutation for which gefitinib was effective. In 2007, he complained of left gluteal pain and right cervical lymph node swelling. He was given a diagnosis of adenocarcinoma at the biopsy of the right cervical lymph node. Although metastases of multiple lymph nodes, bone, and bilateral adrenal glands were found, the primary site could not be determined on close examination, resulting in a diagnosis of cancer of unknown primary site(poor prognosis group). He was then treated with systemic chemotherapy. After he showed resistance to chemotherapy, he received gefitinib as third-line therapy because the tumor harbored an epidermal growth factor receptor(EGFR)mutation. Subsequently, multiple metastatic tumors gradually reduced and clinical benefit was observed for a long time.
    Gan to kagaku ryoho. Cancer & chemotherapy 08/2012; 39(8):1291-4.

Publication Stats

4k Citations
658.73 Total Impact Points


  • 2008–2014
    • Kanazawa University
      • • Cancer Research Institute
      • • Division of Medical Oncology
      Kanazawa, Ishikawa, Japan
  • 2009–2012
    • Kanazawa Medical University
      Kanazawa, Ishikawa, Japan
  • 1994–2008
    • The University of Tokushima
      • • Department of Internal Medicine and Molecular Therapeutics
      • • Department of Pharmacology
      • • Department of Internal Medicine
      Tokusima, Tokushima, Japan
  • 2006
    • RIKEN
      Вако, Saitama, Japan
  • 1999–2004
    • University of Texas MD Anderson Cancer Center
      • Department of Cancer Biology
      Houston, TX, United States
  • 2001
    • Nara Medical University
      Kashihara, Nara, Japan