Makiko Itami

EML4-ALK Fusion Gene Assessment Using Metastatic Lymph Node Samples Obtained by Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration

Purpose: Anaplastic lymphoma kinase (ALK) fusion genes represent novel oncogenes for non–small cell lung cancers (NSCLC). Several ALK inhibitors have been developed, and are now being evaluated in ALK-positive NSCLC. The feasibility of detecting ALK fusion genes in samples obtained by endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) was determined. The clinicopathologic characteristics of ALK-positive lung cancer were also analyzed. Experimental Design: From April 2008 to July 2009, NSCLC cases with hilar/mediastinal lymph node metastases detected by EBUS-TBNA were enrolled. Positive expression of ALK fusion protein was determined using immunohistochemistry, and ALK gene rearrangements were further examined to verify the translocation between ALK and partner genes using fluorescent in situ hybridization and reverse transcription-PCR. Direct sequencing of PCR products was performed to identify ALK fusion variants. Results: One hundred and nine cases were eligible for the analysis using re-sliced samples. Screening of these specimens with immunohistochemistry revealed ALK positivity in seven cases (6.4%), all of which possessed echinoderm microtubule–associated protein-like 4–ALK fusion genes as detected by fluorescent in situ hybridization and reverse transcription-PCR. All ALK-positive cases had an adenocarcinoma histology and possessed no EGFR mutations. Compared with ALK-negative cases, ALK-positive cases were more likely to have smaller primary tumors (P < 0.05), to occur at a younger age (<60 years; P < 0.05), and to occur in never/light smokers (smoking index < 400; P < 0.01). Mucin production was frequently observed in ALK-positive adenocarcinomas (29.4%; P < 0.01). Conclusions: EBUS-TBNA is a practical and feasible method for obtaining tissue from mediastinal and hilar lymph nodes that can be subjected to multimodal analysis of ALK fusion genes in NSCLC. Clin Cancer Res; 16(20); 4938–45. ©2010 AACR.

Comparison of 21-gauge and 22-gauge aspiration needle during endobronchial ultrasound-guided transbronchial needle aspiration

Background and objective:  Endobronchial ultrasound‐guided transbronchial needle aspiration (EBUS‐TBNA) has typically been performed using the 22gauge (G) dedicated TBNA needle. Recently a new 21G TBNA needle has been introduced. The efficacy of using a larger gauge biopsy needle during EBUS‐TBNA has not been reported. The purpose of this study was to compare the diagnostic yield and utility of 21G and 22G needles during EBUS‐TBNA.

Specific mitochondrial DNA mutation in mice regulates diabetes and lymphoma development

It has been hypothesized that respiration defects caused by accumulation of pathogenic mitochondrial DNA (mtDNA) mutations and the resultant overproduction of reactive oxygen species (ROS) or lactates are responsible for aging and age-associated disorders, including diabetes and tumor development. However, there is no direct evidence to prove the involvement of mtDNA mutations in these processes, because it is difficult to exclude the possible involvement of nuclear DNA mutations. Our previous studies resolved this issue by using an mtDNA exchange technology and showed that a G13997A mtDNA mutation found in mouse tumor cells induces metastasis via ROS overproduction. Here, using transmitochondrial mice (mito-mice), which we had generated previously by introducing G13997A mtDNA from mouse tumor cells into mouse embryonic stem cells, we provide convincing evidence supporting part of the abovementioned hypothesis by showing that G13997A mtDNA regulates diabetes development, lymphoma formation, and metastasis—but not aging—in this model.

Non-Hodgkin's lymphoma confined to the nasal cavity: Its relationship to the polymorphic reticulosis and results of radiation therapy

From 1975 through 1988, nine patients with locally confined nasal non-Hodgkins lymphoma (NHL) were treated with radiation therapy in the Department of Radiology, Chiba University Hospital. Immunohistochemical study disclosed that all NHLs have T-lineage. Additionally, unique histological pictures of polymorphism, angiodestruction, and necrosis were seen in most of cases. These three findings are the histological features of polymorphic reticulosis (PMR), which is the main cause of lethal midline granuloma and has recently been shown to belong to T-cell malignancy. Therefore, it is concluded that the nasal T-cell NHL and PMR are really a single disease entity. The predominance of the T-cell lymphoma in the nasal cavity as well as its histological distinctness clearly indicate that the head and neck extranodal NHL cannot be discussed together. Although the disorder was considered to be locally limited at presentation, only 3 of the 9 patients with nasal NHL could be induced into long-term remission with involved field radiotherapy. The distant extranodal spread was the primary cause of failure. Multimodality treatment using intensive chemotherapy might improve the prognosis of nasal NHL.

Preoperative histological subtype classification of intraductal papillary mucinous neoplasms (IPMN) by pancreatic juice cytology with MUC stain.

Objective:To prospectively evaluate the diagnostic value of preoperative histological subtyping of intraductal papillary mucinous neoplasms (IPMNs) by pancreatic juice cytology (PJC) with mucin (MUC) stain. Background:IPMNs are classified into four subtypes based on their histomorphology and mucin phenotype, and varied degrees of malignant nature and prognosis among these subtypes have been shown. Methods:The subjects were 36 patients with surgically confirmed IPMNs, who underwent PJC preoperatively by endoscopic retrograde cholangiopancreatography. Histological subtyping of cytological samples with or without MUC stain (MUC1, MUC2, and MUC5AC) was compared with that of resected specimens. Results:Histologically, low-grade dysplasia was found in 4 patients, intermediate in 10, high grade in 11, and invasive carcinoma in 11. Gastric, intestinal, pancreatobiliary, and oncocytic subtypes corresponded to 16, 14, 5, and 1 patient, respectively. The rate of high-grade dysplasia (HGD) and/or invasive IPMNs was 25% for gastric subtype, 85.7% for intestinal subtype, and 100% for both pancreatobiliary and oncocytic subtypes, showing a significant correlation between histological subtype and rate of HGD and/or invasive IPMN (P < 0.01 for gastric vs nongastric).Histological subtype was successfully diagnosed by PJC in 42% (15/36) without MUC stain, and the rate was significantly improved to 89% (32/36) with MUC stain (P < 0.01). The sensitivity, specificity, and overall accuracy of PJC with MUC stain were 86%, 100%, and 94% for intestinal subtype, respectively. When cytological grade was combined with MUC stain, the diagnosis of HGD/invasive IPMN showed 77.2% sensitivity, 85.7% specificity, and 80.5% accuracy. Conclusions:Preoperative PJC with MUC stain proved to be highly reliable for identifying the histological subtype of IPMN and may provide useful information for deciding surgical indication.

NCYM, a Cis-Antisense Gene of MYCN, Encodes a De Novo Evolved Protein That Inhibits GSK3β Resulting in the Stabilization of MYCN in Human Neuroblastomas

The rearrangement of pre-existing genes has long been thought of as the major mode of new gene generation. Recently, de novo gene birth from non-genic DNA was found to be an alternative mechanism to generate novel protein-coding genes. However, its functional role in human disease remains largely unknown. Here we show that NCYM, a cis-antisense gene of the MYCN oncogene, initially thought to be a large non-coding RNA, encodes a de novo evolved protein regulating the pathogenesis of human cancers, particularly neuroblastoma. The NCYM gene is evolutionally conserved only in the taxonomic group containing humans and chimpanzees. In primary human neuroblastomas, NCYM is 100% co-amplified and co-expressed with MYCN, and NCYM mRNA expression is associated with poor clinical outcome. MYCN directly transactivates both NCYM and MYCN mRNA, whereas NCYM stabilizes MYCN protein by inhibiting the activity of GSK3β, a kinase that promotes MYCN degradation. In contrast to MYCN transgenic mice, neuroblastomas in MYCN/NCYM double transgenic mice were frequently accompanied by distant metastases, behavior reminiscent of human neuroblastomas with MYCN amplification. The NCYM protein also interacts with GSK3β, thereby stabilizing the MYCN protein in the tumors of the MYCN/NCYM double transgenic mice. Thus, these results suggest that GSK3β inhibition by NCYM stabilizes the MYCN protein both in vitro and in vivo. Furthermore, the survival of MYCN transgenic mice bearing neuroblastoma was improved by treatment with NVP-BEZ235, a dual PI3K/mTOR inhibitor shown to destabilize MYCN via GSK3β activation. In contrast, tumors caused in MYCN/NCYM double transgenic mice showed chemo-resistance to the drug. Collectively, our results show that NCYM is the first de novo evolved protein known to act as an oncopromoting factor in human cancer, and suggest that de novo evolved proteins may functionally characterize human disease.

ALK fusion gene positive lung cancer and 3 cases treated with an inhibitor for ALK kinase activity

BACKGROUND Anaplastic lymphoma kinase (ALK) fusion gene-positive lung cancer accounts for 4-5% of non-small cell lung carcinoma. A clinical trial of the specific inhibitor of ALK fusion-type tyrosine kinase is currently under way. METHODS ALK fusion gene products were analyzed immunohistochemically with the materials obtained by surgery or by endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). The echinoderm microtubule-associated protein-like 4(EML4)-ALK or kinesin family member 5B (KIF5B)-ALK translocation was confirmed by the reverse transcription polymerase chain reaction (RT-PCR) and fluorescence in situ hybridization (FISH). After eligibility criteria were met and informed consent was obtained, 3 patients were enrolled for the Pfizer Study of Crizotinib (PF02341066), Clinical Trial A8081001, conducted at Seoul National University. RESULTS Out of 404 cases, there were 14 of EML4-ALK non-small cell carcinoma (NSCLC) and one KIF5B-ALK NSCLC case (8 men, 7 women; mean age, 61.9 years, range 48-82). Except for 2 light smokers, all patients were non-smokers. All cases were of adenocarcinoma with papillary or acinar subtypes. Three were of stage IA, 5 of stage IIIA, 1 of stage IIIB and 6 of stage IV. Ten patients underwent thoracotomy, 3 received chemotherapy and 2 only best supportive care (BSC). One BSC and 2 chemotherapy cases were enrolled for the clinical trial. Patients with advanced stages who received chemotherapy or best supportive care were younger (54.0±6.3) than those who were surgically treated (65.8±10.1) (p<0.05). The powerful effect of ALK inhibitor on EML4-ALK NSCLC was observed. Soon after its administration, almost all the multiple bone and lymph node metastases quickly disappeared. Nausea, diarrhea and the persistence of a light image were the main side effects, but they diminished within a few months. CONCLUSION ALK-fusion gene was found in 3.7% (15/404) NSCLC cases and advanced disease with this fusion gene was correlated with younger generation. The ALK inhibitor presented in this study is effective in EML4-ALK NSCLC cases. A further study will be necessary to evaluate the clinical effectiveness of this drug.

Prognostic factors for local control in nasopharyngeal cancer (NPC)" Analysis by multivariate proportional hazard models

Despite the development of meticulous radiation therapy techniques, the local control of the nasopharyngeal cancer (NPC) remains unsatisfactory. We examined retrospectively the clinicopathologic factors which have impact upon local recurrence-free survival (LRFS) of the 67 patients with NPC who had been irradiated greater than or equal to 40 Gy with curative intent from 1975 through 1988. Three-year LRFS rate was 63%. T stage, histology, the presence of accompanying lymphocytic infiltration, and the properness of radiation therapy had influence upon LRFS with a statistical significance. Multivariate proportional hazard models showed that T stage and pathology retained significance. Radiation therapy properness emerged as a third factor when only the patients irradiated greater than or equal to 60 Gy were included in the analysis. From these results, three groups with low, moderate, and high risk of shortened LRFS could be separated. This risk classification could contribute to the stratification criteria of future study for the improvement of local control by new modalities.

Temozolomide suppresses MYC via activation of TAp63 to inhibit progression of human glioblastoma

Glioblastoma multiforme (GBM) is a highly invasive and chemoradioresistant brain malignancy. Temozolomide (TMZ), a DNA-alkylating agent, is effective against GBM and has become the standard first-line drug. However, the mechanism by which TMZ regulates the progression of GBM remains elusive. Here, we demonstrate that TMZ targets TAp63, a p53 family member, inducing its expression to suppress the progression of human GBM. High levels of TAp63 expression in GBM tissues after TMZ treatment was an indicator of favourable prognosis. In human GBM cells, TMZ-induced TAp63 directly repressed MYC transcription. Activation of this TAp63-MYC pathway by TMZ inhibited human GBM progression both in vitro and in vivo. Furthermore, downregulation of MYC mRNA levels in recurrent GBMs after TMZ treatment correlated with better patient survival. Therefore, our results suggest that the TAp63-mediated transcriptional repression of MYC is a novel pathway regulating TMZ efficacy in GBM.

Successful resection of schwannoma from an intercostal nerve causing bloody pleural effusion: Report of a case

We report a case of schwannoma arising from the 9th intercostal nerve, which caused a bloodstained pleural effusion. The patient, a 37-year-old woman, presented with left-sided back pain. A chest X-ray showed left pleural effusion, which was subsequently found to be bloodstained but without malignant cells. Chest magnetic resonance imaging showed a 76-mm tumor arising from the 9th intercostal nerve. The tumor and intercostal nerve were successfully resected. Histological examination revealed that the tumor comprised spindle cells with both Antoni types A and B patterns. There were necrotic changes and cystic degeneration, but no atypical or mitotic cells. Based on these findings, benign schwannoma was diagnosed. Schwannoma is rarely accompanied by bloody pleural effusion, which we assume was caused by partial tumor rupture. Magnetic resonance imaging proved very useful in localizing and characterizing the tumor in this case.