論文

© 2017 Japanese Society for Investigative Dermatology Background PCTAIRE1 (also known as cyclin-dependent kinase 16 (Cdk16) and PCTK1) is a Cdk family protein that has been implicated in spermatogenesis. We recently revealed the function of PCTAIRE1 in the tumorigenesis of malignancies, including breast and prostate cancers; however, the tumorigenic function of PCTAIRE1 in cutaneous squamous cell carcinoma (SCC) remains unclear. Objective In this study, we investigated the role of PCTAIRE1 in the tumorigenesis of cutaneous SCCs. Methods and results In cutaneous/oral SCC A431, DJM-1, HSC-3 cells, PCTAIRE1 gene-knockdown was found to diminish cell proliferation as assessed by cell counting and clonogenic assays. FACS analyses of annexin V-PI staining and DNA content showed PCTAIRE1 knockdown to cause G2/M arrest followed by apoptosis. The depletion of PCTAIRE1 was found to lead to the accumulation of tumor suppressor p27 and down-regulation of c-Myc. In tumor xenografts of A431 cells, the conditional knockdown of PCTAIRE1 restores p27 protein expression and suppresses tumor growth. Clinically, in primary tumors from patients with SCC, PCTAIRE1 is more highly expressed in malignant lesions than in adjacent normal epidermis. Conversely, expression levels of p27 are significantly lower in SCC than in normal epidermis. Conclusions Our findings reveal a crucial function for PCTAIRE1 in regulating p27, c-Myc levels and tumor growth in cutaneous SCC cells, suggesting that PCTAIRE1 could be a novel target for skin tumor treatment.

Nanocarriers have been used for specific delivery of therapeutic agents to solid tumors based on the enhanced permeability and retention in cancerous tissues. Despite metastasis is the main reason of cancer-related death and a priority for nanocarrier-based therapies, the targeting ability of nanocarriers to the metastatic disease is poorly understood, especially for preangiogenic micrometastases as nanocarriers usually use the malignant neovasculature for enhancing their accumulation. Thus, herein, we studied the ability of micellar nanocarriers incorporating (1,2-diaminocyclohexane)platinum(II) (DACHPt) for treating liver metastases of bioluminescent murine colon adenocarcinoma C-26, during overt and preangiogenic metastatic stages. After intravenous injection, DACHPt-loaded micelles (DACHPt/m) effectively inhibited the tumor growth in both metastatic tumor models. While the anticancer activity of the micelles against overt metastases was associated with their selective accumulation in cancerous tissues having neovasculature, the ability of DACHPt/m to target preangiogenic metastases was correlated with the inflammatory microenvironment of the niche. This targeting capability of polymeric micelles to preangiogenic metastasis may provide a novel approach for early diagnosis and treatment of metastases. © 2014 Elsevier B.V.

Background: Radiotherapy for high-grade meningioma (HGM) is one of the essential treatment options for disease control. However, appropriate irradiation timing remains under debate. The object of this study is to discern which prognostic factors impact recurrence in HGM patients and to propose a risk-stratification system for the application of postoperative radiotherapy. Methods: We retrospectively reviewed 55 adult patients who were diagnosed with Grade II and III intracranial meningioma. Cox regression models were applied to the analysis for impact on early recurrence in HGM patients without postoperative radiotherapy. Results: Grade III malignancy (P = 0.0073) and transformed histology (P = 0.047) proved to be significantly poor prognostic factors of early recurrence by multivariate analysis. The other candidates for recurrence factors were Simpson Grade 3-5 resection, preoperative Karnofsky Performance status < = 70%, and MIB-1 labeling index > = 15%. According to these prognostic factors, postoperative HGM patients could be stratified into three recurrence-risk groups. The prognoses were significantly different between each group, as the 3-year actual recurrence-free rates were 90% in low-risk group, 31% in intermediate-risk group, and 15% in high-risk group. Conclusion: We propose recurrence-risk stratification for postoperative HGM patients using clinically available factors. Our results suggest that the prognosis for patients with high-risk HGMs is dismal, whereas HGM patients belonging to the lowrisk group could have favorable prognoses. This stratification provides us with the criteria necessary to determine whether to apply adjuvant radiotherapy to postoperative HGM patients, and to also help identify potentially curable HGMs without adjuvant radiotherapy. © 2014 Yamaguchi et al.

© 2015 Elsevier Ireland Ltd. Objectives: Several American and Japanese guidelines recommend surgery for patients with c-stage I small-cell lung cancer (SCLC), whereas the European Society of Medical Oncology (ESMO) guidelines recommend surgery for patients with not only c-stage I but also c-stage II (T2N1) SCLC. In addition, previous studies identified various factors other than clinical stage that are related to survival in these patients. Thus, further validation and examination of the association of clinical stage and other clinical variables with survival are required for establishing practical management of early-stage SCLC. Patients and methods: We reviewed the clinical courses of 156 SCLC patients who had undergone surgery at 17 institutions between January 2003 and January 2013. Results: Clinical stages (tumor-node-metastasis [TNM] version 7) of the 156 patients were 98 cases in IA, 14 in IB, 16 in IIA, 7 in IIB, 18 in IIIA, and 3 in IIIB. Median overall survival (OS) was 33.3 months (95% confidence interval: 20.9-45.8). Multivariate analysis revealed that OS was longer in patients either at c-stage II and under, with a maximum tumor diameter of <20 mm, with preoperative diagnosis, without a history or presence of other types of cancer, or who underwent prophylactic cranial irradiation (PCI). Conclusion: These results indicate that a history or presence of other types of cancer might be a major decisive factor for surgery. Patients with c-stages I and II (c-T2N1) can be considered for surgery, and PCI may be useful in patients undergoing surgery in a practical setting, partly supporting the ESMO guidelines.

© 2017 Japan Atherosclerosis Society. Aim: Leukocyte profile has been related to clinical outcome in patients with ST-segment elevation (STE) myocardial infarction (MI). However, whether eosinophil to leukocyte ratio (ELR) predicts clinical outcome in patients who have undergone primary percutaneous coronary intervention (PCI) remains unclear. Therefore, we examined the prognostic value of ELR in this patient population. Methods: We retrospectively analyzed the data of 331 consecutive patients who underwent primary PCI for STEMI between January 2009 and March 2015. All leukocyte types were counted and ELR was calculated for all patients 24 h after hospital admission. The primary study endpoint was major adverse cardiac events (MACEs) within up to one year of follow-up duration. Results: MACEs including cardiac deaths in 9.4% of the patients, MI in 1.5%, and target lesion or vessel revascularization in 10.3%, occurred within one year in 68 patients (20.5%). The mean ELR was significantly lower in patients with MACEs than in patients without MACEs (0.20±0.51 vs. 0.49±0.66, respectively; p＜0.001). An ELR ＜0.1 at 24 h was identified as the best cut-off value for mortality prediction. Multivariate analysis identified that an ELR ＜0.1 (odds ratio [OR] =0.38; 95% confidence interval [CI]=0.22–0.67; p＜0.001) and chronic kidney disease (OR =2.38; CI=1.33– 4.24; p=0.003) are independent predictors of MACEs. Conclusion: In primary PCI patients with STEMI, ELR at 24 h was an independent predictor of MACEs in addition to the usual coronary risk factors and commonly used biomarkers.

Brain tumor-initiating cells (BTICs) have been enriched using antibodies against the cell surface protein CD133; however, the biological relevance and the regulatory mechanism of CD133 expression in human gliomas are not yet understood. In this study, we initially demonstrated that CD133 was overexpressed in high-grade human glioblastomas where CD133-positive cells were focally observed as a micro-cluster. In addition, CD133 transcripts with exon 1A, 1B, or 1C were predominantly expressed in glioblastomas. To elucidate the mechanism regulating this aberrant expression of CD133, three proximal promoters (P1, P2, and P3) containing a CpG island were isolated. In U251MG and T98G glioblastoma cells, the P1 region flanking exon 1A exhibited the highest activity among the three promoters, and this activity was significantly inactivated by in vitro methylation. After treatment with the demethylating agent 5-azacytidine and/or the histone deacetylase inhibitor valproic acid, the expression level of CD133 mRNA was significantly restored in glioma cells. Importantly, hypomethylation of CpG sites within the P1, P2, and P3 regions was observed by bisulfite sequencing in human glioblastoma tissues with abundant CD133 mRNA. Taken together, our results indicate that DNA hypomethylation is an important determinant of CD133 expression in glioblastomas, and this epigenetic event may be associated with the development of BTICs expressing CD133.

© FASEB. Themicroenvironment of pancreatic ductal adenocarcinoma (PDAC) is characterized by a dense fibrotic stroma (desmoplasia) generated by pancreatic cancer-associated fibroblasts (CAFs) derived from pancreatic stellate cells (PSCs) and pancreatic fibroblasts (PFs). Using an unbiased GPCRomic array approach, we identified 82 G-protein-coupled receptors (GPCRs) commonly expressed by CAFs derived from 5 primary PDAC tumors. Comparedwith PSCs and PFs, CAFs have increased expression ofGPR68 (a proton-sensingGPCR), with the results confirmed by immunoblotting, The Cancer Genome Atlas data, and immunohistochemistry of PDAC tumors. Coculture of PSCs with PDAC cells, or incubation with TNF-α, induced GPR68 expression. GPR68 activation (by decreasing the extracellular pH) enhanced IL-6 expression via a cAMP/PKA/cAMP response element binding protein signaling pathway. Knockdown of GPR68 by short interfering RNA diminished low pH-induced production of IL-6 and enhancement of PDAC cell proliferation by CAF conditioned media. CAFs from other gastrointestinal cancers also express GPR68. PDAC cells thus induce expression by CAFs of GPR68, which senses the acidic microenvironment, thereby increasing production of fibrotic markers and IL-6 and promoting PDAC cell proliferation. CAF-expressed GPR68 is a mediator of low-pH-promoted regulation of the tumor microenvironments, in particular to PDAC cell-CAF interaction and may be a novel therapeutic target for pancreatic and perhaps other types of cancers.

© 2019, The Author(s). Epicardial adipose tissue (EAT), a source of adipokines, is metabolically active, but the role of EAT mitochondria in coronary artery disease (CAD) has not been established. We investigated the association between EAT mitochondrial respiratory capacity, adiponectin concentration in the EAT, and coronary atherosclerosis. EAT samples were obtained from 25 patients who underwent elective cardiac surgery. Based on the coronary angiographycal findings, the patients were divided into two groups; coronary artery disease (CAD; n = 14) and non-CAD (n = 11) groups. The mitochondrial respiratory capacities including oxidative phosphorylation (OXPHOS) capacity with non-fatty acid (complex I and complex I + II-linked) substrates and fatty acids in the EAT were significantly lowered in CAD patients. The EAT mitochondrial OXPHOS capacities had a close and inverse correlation with the severity of coronary artery stenosis evaluated by the Gensini score. Intriguingly, the protein level of adiponectin, an anti-atherogenic adipokine, in the EAT was significantly reduced in CAD patients, and it was positively correlated with the mitochondrial OXPHOS capacities in the EAT and inversely correlated with the Gensini score. Our study showed that impaired mitochondrial OXPHOS capacity in the EAT was closely linked to decreased concentration of adiponectin in the EAT and severity of coronary atherosclerosis.

© 2018 Elsevier Ltd Tumour models mimicking in vivo three-dimensional (3D) microenvironments are of increasing interest in drug discovery because of the limitations inherent to current models. For example, preclinical assays that rely on monolayer or spheroid cell cultures cannot easily predict 3D cancer behaviours because they have no vasculature. Furthermore, there are major differences in cancer behaviour between human and animal experiments. Here, we show the construction of 3D blood/lymph-vascularized human stromal tissues that can be combined with cancer cells to mimic dynamic metastasis for real-time throughput screening of secreted proteinases. We validated this tool using three human carcinoma cell types that are known to invade blood/lymph vessels and promote angiogenesis. These cell types exhibited characteristic haematogenous/lymphogenous metastasis and tumour angiogenesis properties. Importantly, these carcinoma cells selectively secreted different matrix metalloproteinases depending on their metastasis stage and target vasculature, suggesting the possibility of developing drugs that can target each secreted proteinase. We conclude that the 3D tissue tool will be a powerful throughput system for predicting cancer cell responses and time-dependent secretion of molecules in preclinical assays.

Harlequin ichthyosis (HI), which is the most severe genodermatosis, is caused by loss-of-function mutations in ABCA12, a member of the ATP-binding cassette transporter family. To investigate the pathomechanism of HI and the function of the ABCA12 protein, we generated ABCA12-deficient mice (Abca12(-/-)) by targeting Abca12. Abca12(-/-) mice closely reproduce the human HI phenotype, showing marked hyperkeratosis with eclabium and skin fissure. Lamellar granule abnormalities and defective ceramide distribution were remarkable in the epidermis. Skin permeability assay of Abca12(-/-) fetuses revealed severe skin barrier dysfunction after the initiation of keratinization. Surprisingly, the Abca12(-/-) mice also demonstrated lung alveolar collapse immediately after birth. Lamellar bodies in alveolar type II cells of the Abca12(-/-) mice lacked normal lamellar structures. The level of surfactant protein B, an essential component of alveolar surfactant, was reduced in the Abca12(-/-) mice. Fetal therapeutic trials with systemic administration of retinoid or dexamethasone, which are effective for HI and respiratory distress, respectively, to the pregnant mother mice neither improved the skin phenotype nor extended the survival period. Our HI model mice reproduce the human HI skin phenotype soon after the initiation of fetal skin keratinization and provide evidence that ABCA12 plays pivotal roles in lung and skin barrier functions.

© 2015 Gekka et al. Background: Extraintestinal manifestations in Crohn's disease (CD) are frequent and well recognized. However, neurological involvement secondary to CD is rare, and there have been few histologically confirmed cases of cerebral vasculitis secondary to CD. Case presentation: A 58-year-old left-handed man with a history of refractory CD who had fever of over 38 °C, progression of CD symptoms, and Gerstmann's syndrome consulted our hospital. Laboratory data showed elevation of C-reactive protein (CRP) and hypoproteinemia. T2-weighted magnetic resonance imaging (MRI) revealed a right parietal high-intensity lesion. Catheter angiography showed segmental multiple narrowing and occlusion in the distal part of the middle cerebral artery and anterior cerebral artery. Angiography also revealed multiple venous occlusions in the affected parietal area. To confirm the diagnosis, the patient underwent open biopsy, and histological examination revealed cerebral vasculitis. The patient was then started on high-dose prednisolone (60 mg/day) in addition to his previous therapy, which included mesalazine, adalimumab, and azathioprine. CRP elevation, hypoproteinemia, and gastrointestinal symptoms immediately improved after starting this treatment. Neurological status improved simultaneously with CD symptom improvement, and follow-up brain MRI revealed a reduction in the size of the right parietal lobe lesion. He returned to normal status and was discharged from our hospital 5 weeks after admission. Conclusion: This is an important case of histologically confirmed cerebral vasculitis associated with CD. The clinical course of our case clearly illustrates the relevance of the occurrence of cerebral vasculitis and the exacerbation of CD.

The recent development of nanotechnology has already produced clinically applicable "nanodrugs," which are largely dependent on a novel concept for the drug delivery system. Thus the elucidation of local pharmacokinetics of nanodrugs is indispensable for the further development of nanomedicine; however, the detailed pathophysiology associated with nano-sized materials especially in pathologic lesions has not been well-described. In this review article, the microscopic appearance of vascular pericytes in addition to endothelial cells is discussed in the normal state and also in several pathological conditions which could be the major targets for nanomedicine. Moreover, the role of stromal tissue including myofibroblasts is also focused on, as well as inflammatory cells. Finally, the significance of disease-specific tissue structure in the establishment of personalized nanomedicine is discussed. © 2014 Elsevier B.V.

SYT-SSX protein, resulted from chromosomal translocation, causes synovial sarcoma, which is a malignant tumor accounting for 10% of soft tissue sarcoma. However, biological functions of SYT (synovial sarcoma translocation), also known as SS18, are largely unclear, whereas it has been proven that Syt-null mice die at early stages of embryonic development. Here, we generated Syt-deficient mice and confirmed the reported phenotypes, including growth retardation, open neural tube and haplo-insufficient lethality, and therefore, there is no doubt that Syt is essential for embryonic development. However, placental defects, described in the earlier report, were rarely seen in our mice and we frequently observed cardiac defect in Syt-deficient mice. As the mechanisms responsible for embryonic lethality seem to be complicate, we performed additional experiments. By using primary cultured embryonic fibroblasts, we showed that Syt(-/-) MEFs deregulate actin organization and suppressed cell migration. These observations suggest that Syt may contribute to the signaling pathway important for various cellular functions in vivo and in vitro, and we propose that Syt-deficient MEFs would be a powerful means to understand the biological roles of SYT in vitro. Laboratory Investigation (2009) 89, 645-656; doi:10.1038/labinvest.2009.25; published online 30 March 2009

A 57-year-old woman was admitted to Hokkaido University Hospital because of dysphagia. Laryngoscopy indicated hypopharyngeal tumor histologically diagnosed as squamous cell carcinoma (SCC). A combination of radiotherapy and chemotherapy was performed for 2 months, and the hypopharyngeal lesion completely regressed. After 4 months, fever, anorexia, and malaise appeared, and chest X-ray and CT indicated two large tumors in the right lung. Transbroncheal lung biopsy (TBLB) specimens were diagnosed as SCC. Laboratory data showed high levels of serum granulocyte colony-stimulating factor (G-CSF) and parathyroid hormone-related protein (PTHrP). Subsequently, positron emission tomography (PET) showed multiple metastases to several organs including the liver, spine, skull, and thigh. Two months after readmission, the patient died with no success of chemotherapy. At autopsy, the lung tumor was clearly positive for both G-CSF and PTHrP on immunohistostaining. Retrospectively, examination showed that the primary pharyngeal tumor was focally positive for these two cytokines. Thus, a certain population of hypopharyngeal cancer producing G-CSF and PTHrP, spread to various organs and contributed to the rapid progression and poor prognosis. This case is presented with a discussion of several other cases in the literature.

Synovial sarcoma accounts for almost 10% of all soft tissue sarcomas, and its prognosis is poor with 5-year survival rates at 36%. Thus, new treatments and therapeutic targets for synovial sarcoma are required. Tumor-initiating cells have been defined by the ability for self-renewal and multipotent differentiation, and they exhibit higher tumorigenic capacity, chemoresistance and radiation resistance, expecting to be a new therapeutic target. In synovial sarcoma, the presence of such stemness remains largely unclear; thus, we analyzed whether synovial sarcoma possessed tumor-initiating cells and explored specific markers, and we discovered that synovial sarcoma cell lines possessed heterogeneity by way of containing a sphere-forming subpopulation highly expressing NANOG, OCT4 and SOX2. By expression microarray analysis, CXCR4 was identified to be highly expressed in the sphere subpopulation and correlated with stem-cell-Associated markers. Inhibition of CXCR4 suppressed the cell proliferation of synovial sarcoma cell lines in vitro. The tumor-initiating ability of CXCR4-positive cells was demonstrated by xenograft propagation assay. CXCR4-positive cells showed higher tumorigenicity than negative ones and possessed both self-renewal and multipotent differentiation ability. Immunohistochemical analysis of 39 specimens of synovial sarcoma patients revealed that CXCR4 strongly correlated with poor prognosis of synovial sarcoma. Thus, we conclude that CXCR4 is the marker of synovial sarcoma-initiating cells, a new biomarker for prognosis and a new potential therapeutic target.

Lymphomatoid granulomatosis (LYG) is a rare multisystem disorder with characteristic angiocentric lymphoproliferative features, most frequently involving the lung, skin, and rarely the CNS. LYG has been classified into three subtypes based on the relative proportions of atypical and inflammatory infiltrating cells. Most systemic LYGs have been shown to be EBV-associated, T-cell rich, B-cell proliferative disorders. Here, we present four cases of LYG arising from the CNS and have analyzed them by immunohistochemistry to assess the phenotype of the infiltrate, and by PCR-SSCP (single-strand conformation polymorphism) analysis for immunoglobulin heavy chain (IgH) and T-cell receptor (TcR) gamma gene rearrangements. Three cases revealed perivascular infiltration of T-cell dominant lymphoid cells, two cases showed monoclonal TcR gamma gene rearrangement, while the remaining case had a B-cell immunophenotype and monoclonal IgH gene rearrangement with EBV genome expression. This is the first report of a gene rearrangement study on CNS-LYG. We confirm that some cases of CNS-LYG are derived from T-cell monoclonal lymphoproliferative disease, although this disease should be classified as a borderline malignancy and should be separated from overt malignant lymphoma of CNS.

Temozolomide (TMZ) is an oral alkylating agent which is widely used in the treatment of glioblastoma (GBM) and is composed of astrocytic and/or oligodendroglial tumors, and the evaluation of O 6 -methylguanine DNA methyltransferase (MGMT) expression is important to predict the response to TMZ therapy. In this study, we conducted immunohistochemical analysis of 117 cases of Japanese GBM including 19 cases of GBM with oligodendroglioma component (GBMO), using a scoring system for quantitative evaluation of staining intensity and proportion of MGMT, and performed survival analysis of these patients. Immunohistochemically, 55 cases (47%) were positive for MGMT with various intensities and proportions (total score (TS)≥2), while 62 cases (53%) were negative (TS=0). The distribution of MGMT expression pattern was not affected by any clinicopathological parameters such as the histological subtype (GBM vs. GBMO), age and gender. The survival analysis of these patients revealed that the minimal expression of MGMT (TS≥2) was a significant unfavorable prognostic factor (P<0.001) as well as resectability (P=0.004). Moreover, multivariate analysis showed that minimal MGMT expression in GBM was the most potent independent predictor for progression free survival (P<0.001) and also overall patient survival (P<0.001). This is the first report employing the scoring system for both staining intensity and proportion to evaluate immunohistochemical MGMT expression in GBM. In addition, our results emphases the clinicopathological values of the immunohistochemical approach for MGMT expression in glioma patients as a routine laboratory examination. © 2014 Japanese Society of Neuropathology.

© Yokouchi et al. The limited number of available treatments for patients with small-cell lung cancer (SCLC) has prompted us to further investigate the biology of SCLC by molecular profiling. We collected formalin-fixed paraffin-embedded tumor samples from 127 patients with SCLC, who had undergone surgery at 16 institutions between January 2003 and January 2013, and analyzed the association between disease-specific survival and protein expression of c-kit, c-Met, epidermal growth factor receptor, human EGFR-related 2, vascular endothelial growth factor receptor II, anaplastic lymphoma kinase, mediator complex subunit 12 (MED12), and transforming growth factor beta receptor II (TGF-βRII) by immunohistochemistry (IHC). Of the 125 evaluable samples, all tumors expressed MED12, and 123 samples (98.4%) expressed TGF-βRII. MED12 was highly expressed in the nucleus in 92% of the positive samples while TGF-βRII was highly expressed in the cytoplasm in 55% of the positive samples. High c-kit expression was an independent favorable prognostic marker confirmed by multivariate analysis (hazard ratio: 0.543, 95% confidence interval: 0.310-0.953, p = 0.033). Both the relapse free-survival and overall survival of patients who underwent adjuvant chemotherapy were statistically longer in those with high c-kit expression (n = 38) than those with intermediate, low, or no c-kit expression (n = 19) (not reached vs 11.6 months, p = 0.021; not reached vs 25.9 months, p = 0.028). IHC for c-kit may offer a prognostic marker for early-stage SCLC, and the results for MED12 and TGF- βRII may suggest the biological characteristics of SCLC. Further investigation of the roles of their related molecules in early stage SCLC is required.

© 2014, Spandidos Publications. All rights reserved. The present study demonstrated that luminal membrane mesothelin expression is a reliable prognostic factor in gastric cancer. Intraductal papillary mucinous neoplasms (IPMNs) often exhibit a spectrum of dysplasia, ranging between adenoma and carcinoma. Therefore, an immunohistochemical analysis of mesothelin expression in IPMN was performed in the present study, focusing on the localization of mesothelin. IPMNs were classified into two groups, IPMNs associated with invasive carcinoma and low-high (L-H) grade dysplasias. The tumors were classified as mesothelin-positive or -negative and in the mesothelin-positive cases, the localization of mesothelin was evaluated as luminal membrane- or cytoplasmic-positive. Among the 37 IPMNs, mesothelin expression was observed in 21 samples (56.8%), including 46.2% (12 out of 26) of the L-H dysplasia and 81.8% (9 out of 11) of the invasive carcinoma samples (P=0.071). Luminal membrane localization was observed in 10 samples (27%), including 15.4% (4/26) of the L-H dysplasia samples and 54.5% (6 out of 11) of the invasive carcinoma samples (P=0.022). Six patients experienced post-operative recurrence, with five of the recurrent tumors exhibiting mesothelin expression and all six exhibiting luminal membrane localization. It was concluded that immunohistochemical examinations for mesothelin expression and localization are clinically useful for prognostic assessments and decision making regarding further treatment subsequent to surgical procedures in patients with IPMN.

© 2015 The Authors. EML4-ALK lung cancer accounts for approximately 3-7% of non-small-cell lung cancer cases. To investigate the molecular mechanism underlying tumor progression and targeted drug sensitivity/resistance in EML4-ALK lung cancer, clinically relevant animal models are indispensable. In this study, we found that the lung adenocarcinoma cell line A925L expresses an EML4-ALK gene fusion (variant 5a, E2:A20) and is sensitive to the ALK inhibitors crizotinib and alectinib. We further established highly tumorigenic A925LPE3 cells, which also have the EML4-ALK gene fusion (variant 5a) and are sensitive to ALK inhibitors. By using A925LPE3 cells with luciferase gene transfection, we established in vivo imaging models for pleural carcinomatosis, bone metastasis, and brain metastasis, all of which are significant clinical concerns of advanced EML4-ALK lung cancer. Interestingly, crizotinib caused tumors to shrink in the pleural carcinomatosis model, but not in bone and brain metastasis models, whereas alectinib showed remarkable efficacy in all three models, indicative of the clinical efficacy of these ALK inhibitors. Our in vivo imaging models of multiple organ sites may provide useful resources to analyze further the pathogenesis of EML4-ALK lung cancer and its response and resistance to ALK inhibitors in various organ microenvironments.