Nobuya Ohara

Increased Incidence of Follicular Lymphoma in the Duodenum

The incidence of indolent lymphomas in the lymph nodes and extranodal regions is quite different. Follicular lymphoma (FL) is most common in the nodes, and it seems to be least common in the gastrointestinal (GI) tract, where mucosa-associated lymphoid tissue lymphoma arises most frequently. The authors report that the incidence of FL is unexpectedly high in the duodenum compared with other portions of the GI tract. FL was detected in only eight of 222 cases of GI lymphoma (3.6%). However, five cases of FL arose in the duodenum, which accounted for 38.5% of 13 duodenal lymphomas. Only in two patients did FL arise in either the stomach or the colorectum, and in the remaining patients FL was widespread with lymphomatous polyposis. Duodenal FL was composed of neoplastic follicles with small cleaved cells in dominance, and the immunophenotype of the lymphoma cells was CD10+, BCL-2+, CD20+, CD75+, CD79+, CD3-, CD5-, cyclin D1-, CD23-, and CD45RO-. All the patients were women age 37 to 66 years (average age, 52.4 yrs). In all patients the lymphoma was present around the ampulla of Vater, and four of five patients showed multiple small-size polyps. Although lymphoma cell infiltration was confined to the submucosa in the four patients examined, the regional lymph nodes were involved partially in two patients without distant metastasis. All patients are alive at 2 to 50 months of follow up (average, 27 mos), which is comparable with the prognosis for indolent nodal lymphomas. These results suggest that the duodenum has a distinct background of histogenesis of the lymphomas and that biopsy specimens from the duodenum with multiple polyps should be examined carefully.

Induction of intrahepatic cholangiocellular carcinoma by liver-specific disruption of Smad4 and Pten in mice

Cholangiocellular carcinoma (CC), the second most common primary liver cancer, is associated with a poor prognosis. It has been shown that CCs harbor alterations of a number of tumor-suppressor genes and oncogenes, yet key regulators for tumorigenesis remain unknown. Here we have generated a mouse model that develops CC with high penetrance using liver-specific targeted disruption of tumor suppressors SMAD4 and PTEN. In the absence of SMAD4 and PTEN, hyperplastic foci emerge exclusively from bile ducts of mutant mice at 2 months of age and continue to grow, leading to tumor formation in all animals at 4-7 months of age. We show that CC formation follows a multistep progression of histopathological changes that are associated with significant alterations, including increased levels of phosphorylated AKT, FOXO1, GSK-3beta, mTOR, and ERK and increased nuclear levels of cyclin D1. We further demonstrate that SMAD4 and PTEN regulate each other through a novel feedback mechanism to maintain an expression balance and synergistically repress CC formation. Finally, our analysis of human CC detected PTEN inactivation in a majority of p-AKT-positive CCs, while about half also lost SMAD4 expression. These findings elucidate the relationship between SMAD4 and PTEN and extend our understanding of CC formation.

Clinical, Histopathological, and Immunogenetic Analysis of Ocular Adnexal Lymphoproliferative Disorders: Characterization of MALT Lymphoma and Reactive Lymphoid Hyperplasia

Malignant lymphomas and reactive lymphoid hyperplasia (RLH) in the ocular adnexa are sometimes difficult to differentiate morphologically and have often been categorized together as a lymphoproliferative disorder. Immunogenotypic characters of these diseases have not yet been well clarified. This study included 76 cases of ocular adnexal lymphoproliferative disorders. These consisted of 52 cases of malignant lymphoma (43 primary and 9 secondary), 22 of RLH, and 2 borderline cases. There were slightly more male than female subjects. Diagnoses were based on morphology and immunophenotypic characteristics. Clonalities were detected by means of polymerase chain reaction (PCR), and immunoglobulin heavy-chain variable region (VH) genes were sequenced in 10 cases of mucosa-associated lymphoid tissue (MALT) lymphoma. MALT lymphoma constituted 86% (37 cases) of the primary lymphomas. MALT lymphomas were more indolent, more rarely disseminated, and had a lower death rate than the other primary lymphomas. Two patients exhibited coexistence of MALT and diffuse large B-cell lymphoma. The average age of patients with RLH was 5.5 years younger than that of those with MALT lymphoma. One of the cases of RLH later progressed to malignant lymphoma. B-cell clonality was detected by PCR in 57%, 55%, and 0% of primary lymphomas, MALT lymphomas and RLHs, respectively. Sequencing of VH genes revealed that the VH3 family was the most commonly expressed germline VH family (70%) and that DP-63, DP-54 and DP-47 genes were frequently found in the MALT lymphomas examined. PCR analysis was useful for differentiation between MALT lymphoma and RLH. Sequence analysis of VH genes showed that an autoimmune mechanism may be involved in the lymphomagenesis of ocular adnexal MALT lymphoma.

Risk factors associated with local recurrence of early gastric cancers after endoscopic submucosal dissection

BACKGROUND Although endoscopic submucosal dissection (ESD) is expected to reduce the local recurrence of gastric cancers, we still experience cases of recurrence after an ESD. OBJECTIVE To characterize clinical and pathologic features of cases with local recurrence of early gastric cancer after an ESD. DESIGN A prospective cohort study. SETTING AND PATIENTS A total of 306 patients with gastric cancers removed by ESD at Okayama University Hospital and Tsuyama Central Hospital between March 2001 and December 2005 were enrolled. INTERVENTION ESD. MAIN OUTCOME MEASUREMENT Local recurrence. RESULTS The incidence of a complete en bloc resection was 80.4% when pathologically evaluated. Within a median follow-up period of 26 months (12-64 months), a local recurrence was found in 7 cases, all of which had been declared incomplete resections. One patient underwent a second ESD, and the remaining 6 underwent a surgical resection. All removed lesions were mucosal cancers. No lymph-node metastases were found in patients with a surgical resection. There was a significant correlation between the incidence of an incomplete resection and that of a local recurrence (P < .0001). Among the clinical characteristics, tumor size (>30 mm vs <20 mm; odds ratio [OR] 16 mm [95% CI, 2.0-130 mm]) and tumor location (upper vs middle or lower; OR 7.6 [95% CI, 1.3-45]) were identified as factors that were significantly associated with the incidence of a local recurrence. LIMITATION Short follow-up duration. CONCLUSIONS The incidence of a local recurrence was strongly associated with that of an incomplete resection. The frequency of a local recurrence also showed significant correlations with the tumor size and location within the stomach.

Reduction of Hematopoietic Cell-Specific Tyrosine Phosphatase SHP-1 Gene Expression in Natural Killer Cell Lymphoma and Various Types of Lymphomas/Leukemias: Combination Analysis with cDNA Expression Array and Tissue Microarray

To investigate the lymphomagenesis of NK/T lymphoma, we comprehensively and systematically analyzed the expression pattern of the human NK/T cell line (NK-YS) genome by cDNA expression array and tissue microarray. We detected significant changes in the gene expression of NK-YS cell line: an increase in 18 and a decrease in 20 genes compared to normal NK cells or peripheral blood mononuclear cells. Among these genes, we found a strong decrease in hematopoietic cell specific protein-tyrosine-phosphatase SH-PTP1 (SHP1) mRNA by cDNA expression array and reverse transcriptase-polymerase chain reaction. Further analysis with standard immunohistochemistry and tissue microarray, which used 207 paraffin-embedded specimens of various kinds of malignant lymphomas, showed that 100% of NK/T lymphoma specimens and more than 95% of various types of malignant lymphoma were negative for SHP1 protein expression. On the other hand, SHP1 protein was strongly expressed in the mantle zone and interfollicular zone lymphocytes in reactive lymphoid hyperplasia specimens. In addition, various kinds of hematopoietic cell lines, particularly the highly aggressive lymphoma/leukemia lines, lacked SHP1 expression in vitro, suggesting that loss of SHP1 expression may be related to not only malignant transformation, but also tumor cell aggressiveness. SHP1 expression could not be induced in either of two NK/T cell lines by phorbol ester, suggesting that genetic impairment or modification with methylation of SHP1 DNA could be one of the critical events in the pathogenesis of NK/T lymphoma. This evidence strongly suggests that loss of SHP1 gene expression plays an important role in multistep tumorigenesis, possibly as an anti-oncogene in the wide range of lymphomas/leukemias as well as NK/T lymphomas.

Expression of connective tissue growth factor in cartilaginous tumors

Connective tissue growth factor (CTGF) predominantly is expressed in hypertrophic chondrocytes and its specific receptors are demonstrated on chondrocytic cells. Therefore, CTGF may be involved in the proliferation and/or differentiation of cartilage cells. In the current study, CTGF expression was examined both in chondrosarcoma and enchondroma to clarify the relation between the expression of CTGF and the grade of malignancy.

Narrow-Band Imaging Provides Reliable Screening for Esophageal Malignancy in Patients With Head and Neck Cancers

OBJECTIVES:The narrow-band imaging (NBI) system is a novel technology that enhances the visualization of microvasculature and mucosal patterns. The aim of this study was to assess the reliability of the NBI system for esophageal cancer screening in patients with head and neck cancers.METHODS:A total of 142 patients with head and neck squamous cell carcinoma (SCC) were examined by NBI endoscopy, followed by Lugol chromoendoscopy between April 2006 and June 2008 at the Okayama University Hospital, Okayama, Japan. Detection of SCC and high-grade intraepithelial neoplasia (HGIN) was conducted.RESULTS:The median age of the patients was 64 years (range: 29–86 years), and approximately three-fourths of all the patients were male. In total, 21 superficial lesions in 16 patients were detected by NBI endoscopy. Of these, 4 lesions were diagnosed histologically as SCC and 11 lesions as HGIN. An additional 22 Lugol-voiding lesions ≥5 mm were detected in 19 patients by Lugol chromoendoscopy. Although 1 of these lesions was diagnosed as HGIN, 21 lesions were diagnosed as low-grade intraepithelial neoplasia or lesions without atypical findings. The sensitivity of NBI endoscopy for detecting esophageal SCC and HGIN was 90.9% (95% confidence interval (CI), 58.7–99.8), specificity was 95.4% (95% CI, 90.3–98.3), and accuracy was 95.1% (95% CI, 90.1–98.0).CONCLUSIONS:NBI seems to be useful and reliable for screening for esophageal SCC in patients with head and neck cancers.

Multi-Step Aberrant CpG Island Hyper-Methylation Is Associated with the Progression of Adult T–Cell Leukemia/Lymphoma

Aberrant CpG island methylation contributes to the pathogenesis of various malignancies. However, little is known about the association of epigenetic abnormalities with multistep tumorigenic events in adult T cell leukemia/lymphoma (ATLL). To determine whether epigenetic abnormalities induce the progression of ATLL, we analyzed the methylation profiles of the SHP1, p15, p16, p73, HCAD, DAPK, hMLH-1, and MGMT genes by methylation specific PCR assay in 65 cases with ATLL patients. The number of CpG island methylated genes increased with disease progression and aberrant hypermethylation in specific genes was detected even in HTLV-1 carriers and correlated with progression to ATLL. The CpG island methylator phenotype (CIMP) was observed most frequently in lymphoma type ATLL and was also closely associated with the progression and crisis of ATLL. The high number of methylated genes and increase of CIMP incidence were shown to be unfavorable prognostic factors and correlated with a shorter overall survival by Kaplan-Meyer analysis. The present findings strongly suggest that the multistep accumulation of aberrant CpG methylation in specific target genes and the presence of CIMP are deeply involved in the crisis, progression, and prognosis of ATLL, as well as indicate the value of CpG methylation and CIMP for new diagnostic and prognostic biomarkers.

XAGE-1 expression in non : Small cell lung cancer and antibody response in patients

Purpose:XAGE-1 was originally identified by the search for PAGE/GAGE-related genes using expressed sequence tag database and was shown to exhibit characteristics of cancer/testis-like antigens. Four transcript variants XAGE-1a, XAGE-1b, XAGE-1c, and XAGE-1d have been identified thus far. We recently identified XAGE-1b as a dominant antigen recognized by sera from lung adenocarcinoma patients. We here investigated the mRNA expression of four XAGE-1 variants and XAGE-1 protein expression in non–small cell lung cancer (NSCLC). Humoral immune response to XAGE-1b was also evaluated in patients. Experimental Design: Forty-nine NSCLC specimens were analyzed for the expression of four XAGE-1 transcript variants by conventional 30-cycle and real-time reverse transcription-PCR and XAGE-1 protein expression by immunohistochemistry. Sera from 74 patients were analyzed for XAGE-1b antibody production by ELISA and Western blot. Results:XAGE-1b and XAGE-1d mRNA were detected in 15 and 6 of 49 lung cancer specimens, respectively. No XAGE-1a or XAGE-1c mRNA expression was observed. XAGE-1b mRNA expression was observed in 14 of 31 (45%) adenocarcinoma and 1 of 18 (6%) lung cancer with other histologic types. Immunohistochemical analysis using a XAGE-1 monoclonal antibody showed that 14 of 15 XAGE-1b mRNA-positive and 3 of 34 XAGE-1b mRNA-negative specimens expressed XAGE-1 protein. Seropositivity was observed in 5 of 56 patients with adenocarcinoma, whereas none of 18 patients with other histologic types produced XAGE-1b antibody. Conclusion: XAGE-1b is highly and strongly expressed in lung adenocarcinoma and immunogenic in patients, suggesting that XAGE-1b is a promising antigen for immunotherapy against lung adenocarcinoma.

Duodenal follicular lymphomas share common characteristics with mucosa-associated lymphoid tissue lymphomas.

Background: Follicular lymphomas occasionally arise in the extra-nodal organs and are frequently found in the duodenum. They are often localised tumours with multiple polyps around the ampulla of Vater. Aims: To examine a IgH/bcl-2 hybrid gene and VH gene to investigate the nature of the lymphoma cells and how they differ from nodal follicular lymphomas and MALT lymphomas. Methods: Of 40 patients reported previously, 35 with duodenal follicular lymphoma were studied in detail with respect to clinicopathological characteristics. Results: 37/40 patients were in clinical stage I (n = 30) or stage II (n = 7). Clonal immunoglobulin gene rearrangement was detected in 53.3% of examined cases, and rearrangement of IgH/bcl-2 gene at the major break point was detected in 27% of cases. Three of 8 examined cases were VH4 (38%); 2 out of them were VH4-34. As VH4 deviation is one of the common characteristics of MALT lymphomas and 2/3 were identical, duodenal follicular lymphomas have a similar aetiology to MALT lymphomas. Clinical course was also similar to that of MALT lymphomas. Conclusions: Results suggest that duodenal follicular lymphomas have intermediate characteristics of MALT lymphomas and nodal follicular lymphomas.