Yukio Takeshima

Increases of Amphiregulin and Transforming Growth Factor-{alpha} in Serum as Predictors of Poor Response to Gefitinib among Patients with Advanced Non-Small Cell Lung Cancers

Serum levels of amphiregulin and transforming growth factor-alpha (TGF-alpha), which were identified previously to be expressed at high levels in non-small cell lung cancer (NSCLC) with poor response to gefitinib, were examined by ELISA using blood samples taken from 50 patients with advanced NSCLCs. Of 14 cases that revealed above the cutoff line for amphiregulin in serum, 12 responded poorly to gefitinib, whereas 18 of the 36 cases showing below the cutoff revealed partial response (PR) or stable disease (SD; P = 0.026). Thirteen of 15 patients who were positive for TGF-alpha responded poorly to gefitinib, whereas 18 of the 35 patients with negative TGF-alpha levels turned out to be relatively good responders (P = 0.014). Of 22 patients with positive values for either or both markers, 19 were poor responders. On the other hand, among 28 patients negative for both markers, 17 were classified into the PR or SD groups (P = 0.001). Gefitinib-treated NSCLC patients whose serum amphiregulin or TGF-alpha was positive showed a poorer tumor-specific survival (P = 0.037 and 0.002, respectively, by univariate analysis) compared with those whose serum amphiregulin or TGF-alpha concentrations were negative. Multivariate analysis showed an independent association between positivity for TGF-alpha and shorter survival times among NSCLC patients treated with gefitinib (P = 0.034). Amphiregulin or TGF-alpha positivity in NSCLC tissues was significantly higher in male, nonadenocarcinomas, and smokers. Our data suggest that the status of amphiregulin and TGF-alpha in serum can be an important predictor of the resistance to gefitinib among patients with advanced NSCLC.

Expression and localization of Reg IV in human neoplastic and non-neoplastic tissues: Reg IV expression is associated with intestinal and neuroendocrine differentiation in gastric adenocarcinoma.

Regenerating islet‐derived family, member 4 (Reg IV) is a candidate marker for cancer and inflammatory bowel disease. In the present study, immunohistochemical analysis of Reg IV was performed in various human neoplastic (n = 289) and non‐neoplastic tissues. In the stomach, foveolar epithelium was negative for Reg IV, whereas goblet cells of intestinal metaplasia and neuroendocrine cells at the base of intestinal metaplasia expressed Reg IV. Neuroendocrine cells of the small intestine and colon showed strong expression of Reg IV, whereas goblet cells of the small intestine and colon showed weak or no expression of Reg IV. Insulin‐producing beta cells of the endocrine pancreas were positive for Reg IV. Among 143 gastric adenocarcinomas, Reg IV expression was detected in 42 (29.4%) and was associated with both the intestinal mucin phenotype and neuroendocrine differentiation. No association was found between Reg IV expression and clinical characteristics such as tumour stage and patient prognosis. Of 36 colorectal adenocarcinomas, 13 (36.1%) were positive for Reg IV, which was associated with tumour stage (p = 0.0379, Fishers exact test). Expression of Reg IV was detected in 14 (93.3%) of 15 colorectal carcinoid tumours. Reg IV expression was also detected in 5 (21.7%) of 23 ductal adenocarcinomas of the pancreas. In contrast, lung cancers (n = 30) and breast cancers (n = 30) did not express Reg IV. This is the first immunohistochemical analysis of the expression and distribution of Reg IV protein in human tumours. These data suggest that Reg IV is expressed by gastrointestinal and pancreatic tumours, including adenocarcinomas and carcinoid tumours, and that Reg IV is associated with intestinal and neuroendocrine differentiation of the stomach and gastric carcinoma. Copyright

p53 mutations in lung cancers from non-smoking atomic-bomb survivors.

Tobacco smoke contains many carcinogens and has been linked with the development of lung cancer. We sequenced the conserved regions of the p53 tumour suppressor gene in lung cancers from 17 non-smokers from Hiroshima, Japan; 9 were atomic-bomb survivors. The mutations were predominantly transitions (all G:C to A:T); there were no G:C to T:A transversions. By contrast, lung cancers from 77 Japanese smokers have a predominance of G:C to T:A transversions in which the guanine residues occur on the non-transcribed DNA strand. These findings further implicate tobacco smoke carcinogens in the molecular pathogenesis of lung cancer.

Immunohistochemical marker panels for distinguishing between epithelioid mesothelioma and lung adenocarcinoma

The distinction between epithelioid mesothelioma and lung adenocarcinoma remains an important diagnostic challenge for surgical pathologists. The aim of the present study was to select a limited and appropriate panel of antibodies that can differentiate between epithelioid mesothelioma and lung adenocarcinoma. Specimens of 90 epithelioid mesotheliomas and 51 lung adenocarcinomas obtained from Japanese cases were examined using calretinin, WT1, AE1/AE3, CAM5.2, cytokeratin (CK) 5/6, vimentin, epithelial membrane antigen (EMA), thrombomodulin, CEA, CA19‐9, and CA125. Ninety‐six percent of epithelioid mesotheliomas were positive for calretinin; 99% for WT1; 100% for AE1/AE; 97% for CAM5.2; 70% for CK 5/6; 91% for vimentin; 96% for EMA; 71% for thrombomodulin; 77% for mesothelin; 7% for CEA; 17% for CA19‐9; and 85% for CA125. In contrast, 33% of lung adenocarcinomas were positive for calretinin; 16% for WT1; 100% for AE1/AE3, CAM5.2, and EMA; 41% for CK 5/6; 47% for vimentin; 20% for thrombomodulin; 69% for mesothelin; 98% for CEA; 73% for CA19‐9; and 80% for CA125. For distinguishing between epithelioid mesothelioma and lung adenocarcinoma, the combination of CEA, calretinin and each WT1 or thrombomodulin was suggested to be the best panel of immunohistochemical markers.

Lymphomas and glioblastomas: Differences in the apparent diffusion coefficient evaluated with high b-value diffusion-weighted magnetic resonance imaging at 3 T

BACKGROUND AND PURPOSE As the usefulness of the apparent diffusion coefficient (ADC) obtained from diffusion-weighted images (DWI) for the differential diagnosis between glioblastoma and primary central nervous system lymphoma is controversial, we assessed whether high b-value DWI at b 4000 s/mm(2) could discriminate between glioblastoma and lymphoma. We also compared the power of high- and standard b-value (b-4000, b-1000) imaging on a 3-Tesla (3T) magnetic resonance (MR) instrument. MATERIALS AND METHODS This study was approved by our Institutional Review Board. We acquired DWI at 3T with b = 1000 and b = 4000 s/mm(2) in 10 patients with lymphoma and 14 patients with glioblastoma. The ADC was measured by placing multiple regions of interest (ROI) on ADC maps of the site of enhanced lesions on contrast-enhanced T1-weighted MR images. We avoided hemorrhagic and cystic lesions by using T1-, T2-, FLAIR-, and T2* MR images. The ADC values of each tumor were determined preoperatively from several ROI and expressed as the minimum-, mean-, and maximum ADC value (ADC(MIN), ADC(MEAN), ADC(MAX)). We evaluated the relationship between ADCs and histological information including tumor cellularity. RESULTS All ADC values were statistically associated with tumor cellularity. ADC(MIN) at b-4000 was associated with tumor cellularity more significantly than ADC(MIN) at b-1000. All ADC values were lower for lymphoma than glioblastoma and the statistical difference was larger at b = 4000- than b = 1000 s/mm(2). According to the results of discriminant analysis, the log likelihood was greatest for ADC(MIN) at b = 4000. At a cut-off value of ADC(MIN) = 0.500 × 10(-3)mm(2)/s at b-4000 it was possible to differentiate between lymphoma and glioblastoma (sensitivity 90.9%, specificity 91.7%). CONCLUSIONS Calculating the ADC value is useful for distinguishing lymphoma from glioblastoma. The lowest degree of overlapping and a better inverse correspondence with tumor cellularity were obtained with ADC(MIN) at b-4000 s/mm(2) at 3T MRI.

Expression of MUC1, MUC2, MUC5AC, and MUC6 in atypical adenomatous hyperplasia, bronchioloalveolar carcinoma, adenocarcinoma with mixed subtypes, and mucinous bronchioloalveolar carcinoma of the lung.

We examined the expression of MUC1, MUC2, MUC5AC, and MUC6 by immunohistochemical staining in atypical adenomatous hyperplasia (AAH), bronchioloalveolar carcinoma (BAC), and adenocarcinoma with mixed subtypes (MX) to study the association between the biologic features of adenocarcinoma of the lung and mucin expression. MUC1 expression was decreased significantly in the progression from AAH through BAC to MX, while the levels of expression of MUC2, MUC5AC, MUC6, and depolarized MUC1 were increased significantly. Alterations in the expression of depolarized MUC1, MUC5AC, and MUC6 were correlated significantly with p53 gene abnormalities. Depolarized MUC1 expression also was correlated significantly with Ki-67 expression, and down-regulation of MUC1 expression and up-regulation of MUC6 expression were correlated significantly with tumor size. Our results suggest that the expression of these mucins might be associated with the progression of adenocarcinoma of the lung.

National survey of malignant mesothelioma and asbestos exposure in Japan

In the present study, malignant mesothelioma (MM) cases in Japan were investigated retrospectively. We extracted records for 6030 cases of death due to MM between 2003 and 2008 to clarify the clinical features of MM, including its association with asbestos exposure (AE). Of all these cases, a clinical diagnosis of MM was confirmed for 929. The origin of MM included the pleura in 794 cases (85.5%), the peritoneum in 123 cases (13.2%), the pericardium in seven cases (0.8%), and the testicular tunica vaginalis in five cases (0.5%). The histological subtypes of MM included 396 epithelioid (55.9%), 154 sarcomatoid (21.7%), 126 biphasic (17.8%), and 33 cases (4.7%) classified as “other types”. Of all the MM cases, AE was indicated in 76.8% and pleural plaques were detected in 34.2%. The number of asbestos particles was determined in 103 cases of MM. More than 1000 asbestos particles per gram dried lung tissue were detected in 74.8% of cases and more than 5000 particles were detected in 43.7% of cases. We compared patient characteristics and the diagnostic procedures for MM before and after the “Kubota shock”. Compared with the early phase of this study (2003–2005), the median age at diagnosis of MM was higher, the number of cases without definite diagnosis of MM was lower, the proportion of cases diagnosed by thoracoscopy was higher, and the percentage of cases in which the occupational history was described in the medical records was significantly higher in the later phase (2006–2008). Our study confirmed that more than 70% of MM cases in Japan are associated with AE. The “Kubota shock” may affect some features pertaining to MM. (Cancer Sci 2012; 103: 483–490)

Characterization of SEZ6L2 cell-surface protein as a novel prognostic marker for lung cancer.

To identify molecules that might serve as biomarkers or targets for development of novel molecular therapies, we have been screening genes encoding transmembrane/secretory proteins that are up‐regulated in lung cancers, using cDNA microarrays coupled with purification of tumor cells by laser microdissection. A gene encoding seizure‐related 6 homolog (mouse)‐like 2 (SEZ6L2) protein, was chosen as a candidate for such molecule. Semi‐quantitative RT‐PCR and western‐blot analyses documented increased expression of SEZ6L2 in the majority of primary lung cancers and lung‐cancer cell lines examined. SEZ6L2 protein was proven to be present on the surface of lung‐cancer cells by flow cytometrical analysis using anti‐SEZ6L2 antibody. Immunohistochemical staining for tumor tissue microarray consisting of 440 archived lung‐cancer specimens detected positive SEZ6L2 staining in 327 (78%) of 420 non‐small cell lung cancers (NSCLCs) and 13 (65%) of 20 small‐cell lung cancers (SCLCs) examined. Moreover, NSCLC patients whose tumors revealed a higher level of SEZ6L2 expression suffered shorter tumor‐specific survival compared to those with no SEZ6L2 expression. These results indicate that SEZ6L2 should be a useful prognostic marker of lung cancers. (Cancer Sci 2006; 97: 737–745)

Methylation of p14 ARF gene in meningiomas and its correlation to the p53 expression and mutation

We have previously reported the statistically significant correlation of immunohistochemical expression of MIB-1 and p53 proteins among benign, atypical, and anaplastic meningiomas and p53 protein expression was high in atypical and anaplastic meningiomas. In the present study, we analyzed 22 cases of meningiomas for mutation of p53 gene in its spectrum of exon 5 to 8 using automated genetic analyzer. We did not find any mutation of p53 in any of these cases, thus suggesting the p53 protein expression is wild type. We analyzed 72 cases of meningiomas for determining the methylation status of p14ARF gene and the immunohistochemical expression of MDM2 protein to explain p53 protein expression in these meningiomas. We found methylation of p14ARF gene in five of 58 cases of benign meningiomas (8.6%), two of 10 cases of atypical meningiomas (20%), and two of four cases of anaplastic meningiomas (50%). In absence of p53 gene mutation, the high percentage of p14ARF gene methylation in high-grade meningioma may have been responsible for accumulation of wild-type p53 protein. In addition, we also found the loss of MDM2 protein in high-grade meningiomas. These deregulations of p14–MDM2–p53 pathway may contribute to the malignant progression of meningioma.

Differential diagnosis of sarcomatoid mesothelioma from true sarcoma and sarcomatoid carcinoma using immunohistochemistry

Differentiation of sarcomatoid mesothelioma from other sarcomatoid tumors involving the pleura and other structures by light microscopy remains an important diagnostic challenge for surgical pathologists. The purpose of the present study was to investigate the utility of diagnostic immunohistochemistry for differentiating sarcomatoid mesothelioma from its histological mimics: true sarcoma and pulmonary sarcomatoid carcinoma. A total of 39 specimens of mesotheliomas with sarcomatoid components, 43 specimens of true sarcomas, and nine specimens of pulmonary sarcomatoid carcinomas were obtained from Japanese patients and examined using a 10‐antibody panel (calretinin, WT1, AE1/AE3, CAM5.2, epithelial membrane antigen, desmin, α‐smooth muscle actin, S‐100 protein, CD34, and CD68). CAM5.2 had the highest sensitivity and specificity for differentiating sarcomatoid mesothelioma from true sarcoma. The combination of CAM5.2, WT1, and AE1/AE3 is recommended for routine pathological diagnosis. Accurate clinical information is necessary for differentiating sarcomatoid mesothelioma from sarcomatoid carcinoma.