ARID1A deficiency in EBV-positive gastric cancer is partially regulated by EBV-encoded miRNAs, but not by DNA promotor hypermethylation

AT-rich interactive domain 1A (ARID1A), which is a tumor suppressor gene, is frequently mutated in Epstein-Barr virus-positive gastric cancer [EBV (+) GC]. While most ARID1A mutations in GC are truncating mutations, leading to loss of ARID1A protein expression, epigenetic modifications appear to contribute to ARID1A deficiency in EBV (+) GC harboring wild-type ARID1A. Based on the significant role of epigenetic modifications in EBV (+) GC that contributes to ARID1A deficiency, the methylation status of ARID1A was evaluated in EBV-infected cells and GC patients using a publicly available microarray and the Cancer Genome Atlas (TCGA) database. EBV-encoded miRNAs that potentially target ARID1A were identified as an additional epigenetic modulator by computational prediction. In vitro experiments were conducted to evaluate how EBV-encoded miRNAs affected ARID1A mRNA and protein levels. In clinical GC samples, the expression of predicted miRNAs and ARID1A and the mutation status of ARID1A was evaluated. As results, ARID1A was not hypermethylated in EBV (+) GC samples or EBV-infected GC cells. EBV infection did not alter ARID1A mRNA levels, suggesting that ARID1A protein deficiency was caused by post-transcriptional gene silencing in ARID1A-WT EBV (+) GC. Overexpression of miR-BART11-3p and miR-BART12, which were identified as miRNAs that potentially bind ARID1A, suppressed ARID1A protein expression in MKN7 and NCI-N87 cells. Highly expressed miR-BART11-3p and miR-BART12 were correlated with decreased ARID1A levels in GC tumors which did not harbor ARID1A mutations. The present findings revealed that ARID1A expression was epigenetically regulated by miR-BART11-3p and miR-BART12 in EBV (+) GC.

Selective sensitivity of EZH2 inhibitors based on synthetic lethality in ARID1A-deficient gastric cancer

BACKGROUND

AT-rich interactive domain 1A (ARID1A) is a tumor suppressor gene that is frequently mutated in gastric cancer (GC). Although ARID1A mutations are not a druggable target for conventional treatments, novel therapeutic strategies based on a synthetic lethal approach are effective for ARID1A-deficient cancers. The histone methyltransferase EZH2 acts in a synthetic lethal manner in ARID1A-mutated ovarian cancer, although its role in GC remains unknown.

METHODS

The selective sensitivity of the EZH2 inhibitors for ARID1A-deficient GC cells was evaluated using cell viability and colony formation assays. The expression of PI3K/AKT signaling genes were investigated using TCGA's cBioPortal database to determine whether the homeostasis between ARID1A and EZH2 is related to cell proliferation and survival via the PI3K/AKT signaling pathway. We also evaluated the phosphorylation of PI3K/AKT signaling proteins in ARID1A knock downed ARID1A-WT GC cells.

RESULTS

EZH2 inhibitors decreased the viability of ARID1A-deficient cells in a dose-dependent manner and demonstrated the selective sensitivity to ARID1A-deficient cells in vitro experiment system. Bioinformatics approach revealed that the PI3K/AKT signaling was tended to be activated in ARID1A-deficient GC enhancing cell viability and, furthermore, down-regulation of EZH2 in ARID1A-deficient GC was related to normalization of PI3K/AKT signaling pathway. The cell experiment revealed that phosphorylated AKT was upregulated in ARID1A-deficent GC cells.

CONCLUSIONS

The present findings provide a rationale for the selective sensitivity of EZH2 inhibitors against ARID1A-deficient GC and suggest the potential efficacy of targeted therapy using EZH2 inhibitors in this patient population.

KRT17 as a prognostic biomarker for stage II colorectal cancer

Adjuvant chemotherapy is considered for patients with stage II colorectal cancer (CRC) characterized by poor prognostic clinicopathological features; however, current stratification algorithms remain inadequate for identifying high-risk patients. To develop prognostic assays, we conducted a step-wise screening and validation strategy using nine cohorts of stage II patients based on multiple platforms, including microarray, RNA-sequencing (RNA-seq) and immunohistochemistry (IHC) on formalin-fixed paraffin-embedded (FFPE) tissues. Four microarray datasets (total n = 458) were used as the discovery set to screen for single genes associated with postoperative recurrence. Prognostic values of candidate genes were evaluated in three independent microarray/RNA-seq validation cohorts (n = 89, n = 93 and n = 183, respectively), and then IHC for KRT17 was conducted in two independent FFPE series (n = 110 and n = 44, respectively). We found that high levels of KRT17 transcript expression were significantly associated with poor relapse-free survival (RFS) not only in the discovery set, but also in three validation cohorts, and its prognostic impact was independent of conventional factors by multivariate analyses. Positive staining of KRT17 protein was significantly associated with poor RFS in two independent FFPE cohorts. KRT17 protein expression had independent prognostic impact on RFS in a multivariate model adjusted for conventional variables, including high-risk clinicopathological features. In conclusion, using nine independent cohorts consisting of 997 stage II patients, we identified and validated the expression of KRT17 transcript and KRT17 protein as a robust prognostic biomarker that can discriminate postoperative stage II patients who are at high probability of disease recurrence, providing additional prognostic stratification beyond the currently available high-risk factors.

Correlation of inflammation-related markers with MDSC and IL-17, and use as prognostic indicators in patients with advanced gastric and colorectal cancers

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Background: Although a causal relationship for inflammation and immunity of cancer is more widely accepted today, the precise cell mechanisms mediating this relationship have not been elucidated. Accumulating evidence suggests that myeloid-derived suppressor cells (MDSC), may contribute to the negative regulation of immune responses during cancer and inflammation. IL-17 is a pro-inflammatory cytokine that is primarily secreted by T helper (Th)17 cells and we have reported that IL-17 correlates with immunosuppressive conditions in patients with cancer. Methods: PBMC (peripheral blood mononuclear cells) were harvested from 106 patients including 43 with gastric and 63 with colorectal cancer. PBMC were stimulated with PHA (phytohemagglutinin) and the production of IL-17 was measured by ELISA. MDSC were detected by flow cytometry (CD11b+,CD14-,CD33+). The levels of CRP (C-reacting protein) and NLR (neutrophil to lymphocyte ratio) were used as inflammatory markers. Results: Both of MDSC and IL-17 production were increased in patients with advanced stages, and correlated with each other, inflammatory markers and immune suppression. The patients were divided with average levels of MDSC and IL-17 production and the prognosis were analyzed with Kaplan-Meier method. The overall survival of patients with high MDSC or high IL-17 production were significantly worse than those with low MDSC or low IL-17 production, respectively, in patients with stages III and IV, although the differences were not significant in patients with stages I and II. Conclusions: Thus these inflammatory markers are closely related with systemic inflammation involving IL-17 and with immunosuppression driven by MDSC, and are effective prognostic indicators in patients with stages III and IV gastric and colorectal cancer.

miRNA-148a-3p Regulates Immunosuppression in DNA Mismatch Repair-Deficient Colorectal Cancer by Targeting PD-L1

Immunotherapy against the interaction between programmed cell death 1/programmed cell death ligand 1 (PD-L1) has emerged as a promising strategy for colorectal cancer with mismatch repair deficiency (dMMR) or microsatellite instability-high (MSI-H). The study aimed to identify miRNAs that posttranscriptionally control PD-L1 expression on tumor cells and also regulate immune evasion. A comprehensive miRNA screening using The Cancer Genome Atlas (TCGA) dataset (n = 260) combined with eight different miRNA target prediction programs resulted in the identification of a tumor suppressive miRNA, miR-148a-3p, as a potential negative regulator of PD-L1 expression, particularly in dMMR/MSI-H colorectal cancer. Using multiple cohorts of colorectal cancer, including TCGA data, a microarray dataset (n = 148), and formalin-fixed, paraffin-embedded samples (n = 395), we found that the expression of miR-148a-3p was decreased in dMMR/MSI-H tumors, correlating inversely with PD-L1 levels. We demonstrate that miR-148a-3p directly binds to the 3'-untranslated region of PD-L1, thereby reducing whole-cell and cell surface PD-L1 levels in HCT116 and SW837 cell lines. Overexpression of miR-148a-3p repressed IFNγ-induced PD-L1 expression on tumor cells and consequently diminished T-cell apoptosis in a coculture model of IL2-activated T cells and IFNγ-treated tumor cells. In conclusion, our data support a regulatory mechanism of PD-L1 expression on tumor cells and immune suppression via miR-148a-3p downregulation in colorectal cancer. IMPLICATIONS: This study provides novel evidence that miR-148a-3p negatively regulates tumor cell PD-L1 expression and decreased levels of miR-148a-3p contributes to the immunosuppressive tumor microenvironment.

Glycosyltransferase Gene Expression Identifies a Poor Prognostic Colorectal Cancer Subtype Associated with Mismatch Repair Deficiency and Incomplete Glycan Synthesis

Purpose: We aimed to discover glycosyltransferase gene (glycogene)-derived molecular subtypes of colorectal cancer associated with patient outcomes.Experimental Design: Transcriptomic and epigenomic datasets of nontumor, precancerous, cancerous tissues, and cell lines with somatic mutations, mismatch repair status, clinicopathologic and survival information were assembled (n = 4,223) and glycogene profiles were analyzed. IHC for a glycogene, GALNT6, was conducted in adenoma and carcinoma specimens (n = 403). The functional role and cell surface glycan profiles were further investigated by in vitro loss-of-function assays and lectin microarray analysis.Results: We initially developed and validated a 15-glycogene signature that can identify a poor-prognostic subtype, which closely related to deficient mismatch repair (dMMR) and GALNT6 downregulation. The association of decreased GALNT6 with dMMR was confirmed in multiple datasets of tumors and cell lines, and was further recapitulated by IHC, where approximately 15% tumors exhibited loss of GALNT6 protein. GALNT6 mRNA and protein was expressed in premalignant/preinvasive lesions but was subsequently downregulated in a subset of carcinomas, possibly through epigenetic silencing. Decreased GALNT6 was independently associated with poor prognosis in the IHC cohort and an additional microarray meta-cohort, by multivariate analyses, and its discriminative power of survival was particularly remarkable in stage III patients. GALNT6 silencing in SW480 cells promoted invasion, migration, chemoresistance, and increased cell surface expression of a cancer-associated truncated O-glycan, Tn-antigen.Conclusions: The 15-glycogene signature and the expression levels of GALNT6 mRNA and protein each serve as a novel prognostic biomarker, highlighting the role of dysregulated glycogenes in cancer-associated glycan synthesis and poor prognosis. Clin Cancer Res; 24(18); 4468-81. ©2018 AACR.

Prognostic role of FUT8 expression in relation to p53 status in stage II and III colorectal cancer

The expression of fucosyltransferase 8, an enzyme responsible for core fucosylation encoded by FUT8, influences tumor biology and correlates with patient prognosis in several solid cancers. We hypothesized that p53 alteration modifies prognostic associations of FUT8 expression in colorectal cancer (CRC), since FUT8 has recently been identified as a direct transcriptional target of wild-type p53. Utilizing multiple datasets of microarray and RNA sequence of CRC, FUT8 mRNA was found to be highly expressed in wild-type p53 tumors (n = 382) compared to those of mutant p53 (n = 437). Prognostic values of FUT8 expression in conjunction with the p53 status for disease-free survival (DFS) were analyzed using two independent cohorts of stage II and III CRC after curative surgery, including the immunohistochemistry (IHC) cohort (n = 123) and the microarray cohort (n = 357). In both cohorts, neither FUT8 expression nor the p53 status was associated with DFS. Strikingly, positive expression of FUT8 protein was significantly associated with better DFS only in tumors with negative p53, while it had no prognostic impact in tumors with positive p53 in the IHC cohort. Although not statistically significant, a similar prognostic trend was observed in the microarray cohort when patients were stratified by the p53 status. Our results suggest that the prognostic values of FUT8 expression on DFS may be modified by the p53 status, and the expression of FUT8 protein can be a prognostic biomarker for patients with stage II and III CRC.

Epithelial-mesenchymal transition-converted tumor cells can induce T-cell apoptosis through upregulation of programmed death ligand 1 expression in esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is an aggressive tumor, and it is urgently needed to develop novel therapeutic strategies including immunotherapy. In this study, we investigated the upregulation of the programmed death ligand 1 (PD‐L1) due to epithelial‐mesenchymal transition (EMT) in ESCC using an in vitro treatment system with the EMT inducer, glycogen synthase kinase (GSK)‐3 inhibitor, and we also analyzed the correlation of EMT and PD‐L1 expression in the clinical tumor samples of both tissue microarray (TMA) samples (n = 177) and whole tissue samples (n = 21). As a result, the inhibition of GSK‐3β induces EMT phenotype with upregulated vimentin and downregulated E‐cadherin as well as increased Snail and Zinc finger E box‐binding homeobox (ZEB)‐1 gene expression. Simultaneously, we showed that EMT‐converted ESCC indicated the upregulation of PD‐L1 at both protein (total and surface) and mRNA levels. Of importance, we showed that EMT‐converted tumor cells have a capability to induce T‐cell apoptosis to a greater extent in comparison to original epithelial type tumor cells. Furthermore, the immunohistochemical stains of ESCC showed that PD‐L1 expression on tumor cells was positively correlated with EMT status in TMA samples (P = .0004) and whole tissue samples (P = .0029). In conclusion, our in vitro and in vivo study clearly demonstrated that PD‐L1 expression was upregulated in mesenchymal type tumors of ESCC. These findings provide a strong rationale for the clinical use of anti‐PD‐1/anti‐PD‐L1 monoclonal antibodies for advanced ESCC patients.

Correlation of IL-17 with immune suppression involving MDSC, malnutrition, and prognosis in patients with gastric and colorectal cancer

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Background: Although a causal relationship linking inflammation and cancer immunity is more widely accepted today, precise cell mechanisms mediating this relationship have not been elucidated. IL-17, a pro-inflammatory cytokine primarily secreted by T helper (Th)17 cells, has previously been associated with inflammatory processes in autoimmune disease. The presence of IL-17 and Th17 cells has been confirmed in various invasive cancers and recently linked to immunosuppression in cancer patients. We investigated systemic inflammation, immune suppression, malnutrition, and prognosis associated with IL-17 in patients with gastric and colorectal cancer. Methods: We measured IL-17 in 106 patients, including 43 with gastric and 63 with colorectal cancer, Production of IL-17 stimulated by PHA was measured by ELISA. MDSC (myeloid-derived suppressor cells), which significantly contribute to immunosuppression, were measured by flow cytometry (CD11b+CD14-CD33+). Neutrophil-to-lymphocyte ratio (NLR) and C-reactive protein (CRP) were used as inflammatory markers. Production of IL-12 and the SI (stimulation index) of lymphocytes’ blastogenic response were used as markers of cell-mediated immune response. Results: Production of IL-17 increased in advanced stages of gastric and colorectal cancer. IL-17 positively correlated with levels of MDSC, serum concentrations of VEGF, NLR, and levels of CRP, and was inversely correlated with IL-12 production, SI, and nutritional markers including prealbumin and retinol binding protein. Patient cohorts were divided into two groups with IL-17 level (540 pg/ml) and OS (overall survival) of patients with stages III and IV gastric or colorectal cancer both significantly worse in patients with high production of IL-17 than in those with low IL-17, although the differences were not significant in patients at stages I and II. Conclusions: The present study suggests that IL-17 may reflect an inflammatory impact on the advancement and progression of cancer, and it may serve as useful marker of immune suppression involving MDSC, malnutrition, and poor prognosis in patients with gastric and colorectal cancer.

Identification of microRNAs that target PD-L1 in mismatch repair-deficient colorectal cancer

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Background: Programmed cell death 1 (PD-1) / PD-ligand 1 (PD-L1) immune checkpoint blockade has emerged as a promising therapeutic strategy in various types of cancer. Here we report that certain microRNAs (miRNAs) are involved in immunosuppressive microenvironment by directly targeting PD-L1 in mismatch repair deficient (dMMR) colorectal cancer (CRC). Methods: We identified candidate miRNAs by using RNA-sequence analyses for mRNA and miRNA expression obtained from The Cancer Genome Atlas (TCGA) Colon Adenocarcinoma combined with miRNA target prediction programs. HCT116 and SW837 CRC cell lines were transfected with miRNA mimics and inhibitors, and PD-L1 expression was examined by qRT-PCR, western blotting and flow cytometry. The CRC cell lines were co-cultured with activated T cells and then cytotoxicity for T cells were evaluated. Results: Using miRNA expression profiles of 260 tumors obtained through TCGA Colon Adenocarcinoma, 47 miRNA probes were found to be inversely correlated with PD-L1 expression. Among them, 19 mature miRNAs were down-regulated in dMMR tumors. Furthermore, eight in silico miRNA-target prediction programs were utilized to identify candidate miRNAs that target the 3’UTR of PD-L1 mRNA. We found that forced miRNA expression decreased PD-L1 expression in protein (total and surface) and mRNA levels, and they also dramatically decreased IFN-induced cell surface PD-L1 expression by 32% in CRC cell lines. Furthermore, we found that forced miRNA expression decreased PD-L1 associated apoptotic cell death in co-cultured activated T cells. Conclusions: Our findings suggest that PD-L1 expression is at least in part regulated by miRNAs and may also suggest potential miRNAs to serve as biomarkers and therapeutic targets for cancer immunotherapy.

Correlation of VEGF with immune suppression involving MDSC, malnutrition, and prognosis in patients with gastric and colorectal cancer

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Background: Although a causal relationship for inflammation and immunity of cancer is more widely accepted today, the precise cell mechanisms mediating this relationship have not been elucidated. Vascular endothelial growth factor (VEGF), previously known as vascular permeability factor. 45 kDa protein, belongs to a family of platelet-derived growth factors. VEGF, inflammation-related protein, could contribute to the accumulation of immunosuppressive cells (MDSC, Treg, TAM, and Tie-2-expressingmonocytes) in tumor-bearing hosts through direct or indirect mechanisms. Methods: We tested the serum levels of VEGF by ELISA in 106 patients including 43 with gastric and 63 with colorectal cancer, and they were increased in advanced stages of gastric and colorectal cancer. Production of IL-17, pro-inflammatory cytokine, with a stimulation of PHA was measured by ELISA and MDSC (myeloid-derived suppressor cells), one of major immunosuppressing cells, was measured by flow cytometry (CD11b+CD14-CD33+). Neutrophil to lymphocyte ratio (NLR) and C-reactive protein (CRP) were used as inflammatory markers. Production of IL-12 and SI (stimulation index) of blastogenic response of lymphocytes were used as markers of cell-mediated immune response. Results: The concentrations of VEGF were positively correlated with levels of MDSC, production of IL-17, NLR and CRP, and were inversely correlated with IL-12 production, SI and nutritional markers including prealbumin and retinol binding protein. The patients were both divided into two groups with a serum level of VEGF (330 pg/ml) and OS (overall survival) of patients with stages III and IV gastric or colorectal cancer were both significantly worse in patients with high levels of VEGF than in those with low VEGF although the differences were not significant in patients with stagesⅠand II. Conclusions: The results of the present study suggested that VEGF may have an impact on advancement and progression involving inflammation and serve as useful markers of the immune suppression involving MDSC, malnutrition and poor prognosis in patients with gastric and colorectal cancer.

Abstract A130: ANXA1 is involved in resistance to 5-FU in colon cancer cells

Annexin A1 (ANXA1), which belongs to the annexin superfamily, is a 37 kDa calcium-dependent phospholipid-linked protein that is associated with regulation of cellular differentiation, proliferation, and apoptosis, anti-inflammatory effects, and drug resistance. Through these functions, ANXA1 is considered to be associated with cancer development and metastasis in various malignant tumors. We previously reported that a case of positive ANXA1 expression by immunohistochemical (IHC) staining in colorectal cancer was associated with venous invasion (P=0.023) as well as lymph node metastasis (P=0.042). We therefore performed further investigation of the role of ANXA1 in colorectal cancer metastasis and treatment. In vitro cell experiments revealed that ANXA1 expression was significantly induced in the colon cancer cells resistant to 5-FU compared to the control cells. We then revealed that overexpression of ANXA1 induced a significant increase of cell viability to 5-FU, whereas ANXA1 knockdown induced a significant decrease of cell viability to 5-FU. Further experiments revealed that ANXA1 expression was induced by hypoxia in colon cancer cells, inducing cellar invasion. These results suggest that ANXA1 expression may be induced by hypoxia during colorectal cancer progression and metastasis. Our results provide a possible strategy to overcome 5-FU resistance by modulating ANXA1 expression.

Citation Format: Motonobu Saito, Hisashi Onozawa, Misato Sakuyama, Mai Ashizawa, Tomohiro Kikuchi, Hirokazu Okayama, Hisahito Endo, Shotaro Fujita, Wataru Sakamoto, Zenichiro Saze, Tomoyuki Momma, Shinji Ohki, Koji Kono. ANXA1 is involved in resistance to 5-FU in colon cancer cells [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2017 Oct 26-30; Philadelphia, PA. Philadelphia (PA): AACR; Mol Cancer Ther 2018;17(1 Suppl):Abstract nr A130.

Augmentation of antibody-dependent cellular cytotoxicity with defucosylated monoclonal antibodies in patients with GI-tract cancer

Enhancement of antibody-dependent cellular cytotoxicity (ADCC) with some modalities may be a promising approach to enhance the efficacy of therapeutic monoclonal antibodies (mAbs). It has previously been demonstrated that the removal of fucose from antibody oligosaccharides (defucosylation) leads to augmentation of ADCC activity. To establish clinically relevant evidence of this procedure, the present study evaluated trastuzumab- and cetuximab-mediated ADCC by comparing defucosylated mAbs with conventional mAbs using peripheral blood mononuclear cells (PBMCs). PBMCs were isolated from 20 patients with gastrointestinal tract cancer and 10 healthy volunteers. ADCCs were measured using PBMCs as effector cells and two gastric cancer cell lines as target cells. ADCCs were significantly enhanced with defucosylated mAbs compared with conventional mAbs using PBMC from the healthy donors and patients with cancer. The results confirmed that the cetuximab- and trastuzumab-mediated ADCCs in advanced disease were impaired in comparison to those in early disease or healthy individuals. However, when the defucosylated mAbs were used instead of the conventional mAbs, the ADCC activities in the advanced cases were almost comparable with those in early disease or healthy individuals. Furthermore, the expression of ADCC associated molecules were modified toward immunosuppressive status with a mitogen-activated protein kinase inhibitor in vitro, the conventional cetuximab- and trastuzumab-mediated ADCC was downregulated, and the defucosylated mAbs overcome the downregulation of ADCC. In conclusion, defucosylated therapeutic mAbs may enhance ADCC activities in patients with cancer, which may lead to more effective anti-cancer treatments.

[Regulation of PD-L1 by MicroRNA in Mismatch Repair Deficient-Colorectal Cancer]

Programmed cell death 1(PD-1)/PD-ligand 1(PD-L1)immune checkpoint blockade has emerged as a promising therapeutic strategy in various types of cancer. In a recent phase II clinical trial, treatment with the anti-PD-1 agent, pembrolizumab, resulted in considerable clinical benefit in patients with mismatch repair(MMR)-deficient colorectal cancer(CRC). Upregulation of PD-1on T-cells and PD-L1 on tumor cells induces inhibitory signals to suppress T-cell activation, leading to an immune-suppressive microenvironment particularly in MMR-deficient tumors. However, the regulation of PD-L1 expression on CRC cells is poorly understood. We hypothesized that certain microRNAs(miRNAs)are involved in the immunosuppressive microenvironment by directly targeting PD-L1. We identified candidate miRNAs by RNA-sequence analyses for mRNA and miRNA expression obtained from the TCGA colon adenocarcinoma database combined with miRNA target prediction programs. We found that forced miRNA expression could decrease PD-L1 expression on cancer cell lines. Our findings may facilitate an understanding of the role of miRNAs in PD-L1 regulation and also suggest potential miRNAs to serve as biomarkers and therapeutic targets for cancer immunotherapy.

Identification of Three Novel Fusion Oncogenes, SQSTM1/NTRK3, AFAP1L2/RET, and PPFIBP2/RET, in Thyroid Cancers of Young Patients in Fukushima

BACKGROUND

The BRAF^V600E mutation is the most frequent genetic abnormality in adult papillary thyroid carcinomas (PTCs). On the other hand, various chromosomal rearrangements are more prevalent in childhood and adolescent PTCs. The aim of the present study was to identify novel rearrangements in PTCs from young patients.

METHODS

Among 63 postoperative specimens of childhood and adolescent PTCs, which had been discovered by the thyroid ultrasound screening program in Fukushima, nine samples without prevalent known oncogenes, BRAF^V600E, RAS, RET/PTC1, RET/PTC3, and ETV6/NTRK3, were analyzed in the current study by quantitative real-time reverse transcription polymerase chain reaction to screen for novel fusion genes by comparing transcript expression between extracellular and kinase domains of ALK, NTRK1, NTRK3, and RET.

RESULTS

Of the above nine samples, five samples were suspected to harbor a fusion, and using subsequent 5' rapid amplification of cDNA end (RACE), two already reported fusion oncogenes, STRN/ALK and TPR/NTRK1, and three novel fusions, SQSTM1/NTRK3, AFAP1L2/RET, and PPFIBP2/RET, were identified. Functional analyses of these three chimeric genes were performed, and their transforming abilities were confirmed through the activation of mitogen-activated protein kinase (MAPK).

CONCLUSIONS

Three novel fusion oncogenes have been identified in young PTC patients in Fukushima, suggesting that rare fusions may be present among the cases negative for known oncogenes in this age group and that such rearrangements can play a significant role in thyroid carcinogenesis.

Manganese dioxide nanowires on carbon nanofiber frameworks for efficient electrochemical device electrodes

Hierarchically nanostructured composite electrodes were prepared by the electrodeposition of manganese dioxide nanowires (MnO₂ NWs) with 5–20 nm diameters on electrospun carbon nanofiber (CNF) webs with diameters of 250 and 650 nm.

Risk factors for pre- and post-engraftment bloodstream infections after allogeneic hematopoietic stem cell transplantation

BACKGROUND

Bloodstream infections (BSI) are frequently observed after allogeneic hematopoietic stem cell transplant (HSCT), and could cause morbidity and mortality.

METHODS

We retrospectively evaluated the incidence, characteristics of, and risk factors for BSI at both pre- and post-engraftment in 209 adult HSCT patients at our institute between June 2006 and December 2013. The median age at transplantation was 45 years (range, 15-65). A total of 122 patients received bone marrow, 68 received peripheral blood stem cells, and 19 received umbilical cord blood.

RESULTS

The cumulative incidences of pre- and post-engraftment BSI were 38.9% and 17.2%, respectively. Nine patients had both pre- and post-engraftment BSI. In the pre- and post-engraftment periods, respectively, 67.4% and 84.1% of isolates were gram-positive bacteria (GPB), 28.3% and 11.4% were gram-negative bacteria (GNB), and 4.3% and 4.5% were fungi. Coagulase-negative staphylococci were the most commonly isolated GPB, while Stenotrophomonas maltophilia and Pseudomonas aeruginosa were the most commonly isolated GNB. Pre-engraftment BSI was associated with an increased risk of death. Overall survival at day 180 for patients with or without pre-engraftment BSI was 70.0% and 82.7%, respectively (P = 0.02).

CONCLUSIONS

Risk factors for BSI in the pre-engraftment period were the interval between diagnosis and transplantation (261 days or more), engraftment failure, and high-risk disease status at HSCT in a multivariate analysis. No significant risk factor for BSI in the post-engraftment period was identified by a univariate analysis. These findings may be useful for deciding upon empiric antibacterial treatment for HSCT recipients.

Economic evaluation of a preemptive treatment strategy for invasive fungal infection in neutropenic patients with hematological diseases

We compared the expected medical costs of empirical and preemptive treatment strategies for invasive fungal infection in neutropenic patients with hematological diseases. Based on the results of two clinical trials with different backgrounds reported by Oshima et al. [J Antimicrob Chemother 60(2):350-355; Oshima study] and Cordonnier et al. [Clin Infect Dis 48(8):1042-1051; PREVERT study], we developed a decision tree model that represented the outcomes of empirical and preemptive treatment strategies, and estimated the expected medical costs of medications and examinations in the two strategies. We assumed that micafungin was started in the empirical group at 5 days after fever had developed, while voriconazole was started in the preemptive group only when certain criteria, such as positive test results of imaging studies and/or serum markers, were fulfilled. When we used an incidence of positive test results of 6.7 % based on the Oshima study, the expected medical costs of the empirical and preemptive groups were 288,198 and 150,280 yen, respectively. Even in the case of the PREVERT study, in which the incidence of positive test results was 32.9 %, the expected medical costs in the empirical and preemptive groups were 291,871 and 284,944 yen, respectively. A sensitivity analysis indicated that the expected medical costs in the preemptive group would exceed those in the empirical group when the incidence of positive test results in the former was over 34.4 %. These results suggest that a preemptive treatment strategy can be expected to reduce medical costs compared with empirical therapy in most clinical settings.

Immunosuppression involving increased myeloid-derived suppressor cell levels, systemic inflammation and hypoalbuminemia are present in patients with anaplastic thyroid cancer

Anaplastic thyroid carcinoma (ATC) is one of the most aggressive neoplasms in humans and myeloid-derived suppressor cells (MDSCs) contribute to the negative regulation of immune responses in the context of cancer and inflammation. In order to investigate the pathophysiology of thyroid cancer, peripheral blood mononuclear cells (PBMCs) were obtained from 49 patients with thyroid cancer, 18 patients with non-cancerous thyroid diseases and 22 healthy volunteers. The MDSC levels were found to be higher in patients with any type of thyroid cancer (P<0.05), patients with ATC (P<0.001) and patients with medullary thyroid carcinoma (P<0.05), when compared to patients with non-cancerous thyroid diseases. The MDSC levels were also higher in patients with stage III-IV thyroid cancer compared to those in patients with non-cancerous thyroid diseases (P<0.05). The stimulation index (SI) of phytohemagglutinin (PHA)-induced lymphocyte blastogenesis was significantly lower, the C-reactive protein (CRP) levels were significantly higher and the serum albumin levels were significantly lower in patients with ATC compared to those in patients with non-cancerous thyroid diseases. The SI was significantly lower in stage III and IV thyroid cancer compared to that in non-cancerous thyroid disease (P<0.05). Furthermore, the CRP levels were higher and the concentration of albumin was lower in stage IV thyroid cancer compared to those in non-cancerous thyroid disease (P<0.05). Patients with thyroid carcinoma were then classified into one of two groups according to a %PBMC of MDSC cut-off level of 1.578, which was the average %PBMC of MDSC of patients with any type of thyroid carcinoma. In patients with higher MDSC levels, the production of CRP and interleukin (IL)-10 was significantly higher (P<0.05) and the albumin levels were significantly lower (P<0.05) compared to those in patients with lower MDSC levels. These data indicate that MDSCs are increased in patients with ATC. Furthermore, these patients exhibited suppression of cell-mediated immune responses, chronic inflammation and nutritional impairment.

Low-dose acyclovir prophylaxis for the prevention of herpes simplex virus disease after allogeneic hematopoietic stem cell transplantation

BACKGROUND

Currently, acyclovir (ACV) at 1000 mg/day is widely used as prophylaxis in the early phase of hematopoietic stem cell transplant (HSCT) in Japan. However, low-dose ACV (200 mg/day) has been shown to prevent varicella zoster virus reactivation in the middle and late phases of HSCT.

METHODS

Therefore, in this study, we decreased the dose of ACV to 200 mg/day in the early phase after HSCT. We analyzed 93 consecutive herpes simplex virus (HSV)-seropositive patients who underwent allogeneic HSCT for the first time in our center between June 2007 and December 2011.

RESULTS

Before August 2009, 38 patients received oral ACV at 1000 mg/day (ACV1000) until day 35 after HSCT, whereas 55 patients received oral ACV at 200 mg/day (ACV200) after September 2009. We compared the cumulative incidence of HSV infection in the 2 groups. Oral ACV was changed to intravenous administration because of intolerance in 66% and 45% of the patients in the ACV1000 and ACV200 groups, respectively (P = 0.060). The probability of severe stomatitis (Bearman grade II-III) was 76% and 60% in the ACV1000 and ACV200 groups, respectively (P = 0.12). The number of patients who developed HSV disease before day 100 after HSCT was 0 in the ACV1000 group and 2 in the ACV200 group, with a cumulative incidence of 3.6% (P = 0.43). HSV disease in the latter 2 patients was limited to the lips and tongue and was successfully treated with ACV or valacyclovir at a treatment dose.

CONCLUSION

ACV at 200 mg/day appeared to be effective for preventing HSV disease in the early phase after HSCT.

Malformation surveillance and maternal drug exposure: the MADRE project

A project implemented within the framework of the International Clearinghouse for Birth Defect Monitoring Systems is named MADRE: MAlformation DRug Exposure surveillance. The idea is to survey the simultaneous occurrence of malformations and first-trimester drug exposures. In a 2-year period 1990-91, this has yielded 1448 infants known to have been exposed to drugs and that are known to have malformations. Cases have been reported by eight programs: Australia, Central-East France, Israel, Italy IPIMC, Italy IMER, Japan Red Cross Hospitals, Japan Maternal Health and Welfare, and South America. By searching this databank for associations between drugs and malformations, specific relationships can be detected.The 9th revision of the WHO International Classification of Diseases, adapted by the British Paediatric Association, known as ICD9/BPA is used for coding malformations. This is a hierarchical system with 5 digits as the maximum level of specification of each malformation.The ATC (Anatomical Therapeutic Chemical) classifications system is used for coding drugs. This is a multiple level, hierarchical classification with up to 7 digits for specifying each drug.Up to five drugs and malformations are coded for each case using ATC and ICD9/BPA classifications, and all observed drug-malformation pairs form the basis for the analysis. For each drug-malformation combination where three or more cases are observed, a set of 2×2 tables is formed and analyzed as in case-control studies. The odds ratio for the pair, stratified for program, gives the relative risk for the malformation in question, comparing use of the specific drug with all other drugs.Well known or controversial associations were tested in the collected material, and at this stage only one new association is suggested, that is between cardiac defects and maternal treatment with thyroid hormones. This finding has to be further explored with new data.

Hyperbilirubinemia in the early phase after allogeneic HSCT: prognostic significance of the alkaline phosphatase/total bilirubin ratio

Hyperbilirubinemia in the early phase after allogeneic hematopoietic SCT (HSCT) is due to various causes. One of the most important causes of hyperbilirubinemia is veno-occlusive disease/sinusoidal obstructive syndrome (VOD/SOS). However, the prognosis of patients who are clinically diagnosed as SOS varies. We retrospectively evaluated 82 patients who underwent their first allogeneic HSCT. GVHD prophylaxis was a combination of short-term MTX and CsA (n=77) or tacrolimus (n=5). Thirty-three patients developed hyperbilirubinemia, with a bilirubin level of at least 2 mg/dL, within 20 days after HSCT. Of these patients, 24 were diagnosed as VOD/SOS using the modified Seattle criteria. Twenty-six recovered to a bilirubin level of <2 mg/dL. We focused on the serum alkaline phosphatase/total bilirubin ratio (ALP/TB) at the onset of hyperbilirubinemia and found that it significantly predicted the recovery from hyperbilirubinemia. OS was significantly higher in patients with a lower ALP/TB ratio (P=0.00056). In addition, a lower ALP/TB ratio was associated with better survival even in patients who were clinically diagnosed as SOS (P<0.001). The ALP/TB ratio at the onset of hyperbilirubinemia may be a useful predictor for the prognosis of hyperbilirubinemia and SOS early after HSCT.

Varicella zoster virus meningoencephalitis after allogeneic hematopoietic stem cell transplantation

Although the reactivation of varicella zoster virus (VZV) is a common complication after allogeneic hematopoietic stem cell transplantation (HSCT), VZV meningoencephalitis is a rare life-threatening infectious disease after HSCT. We describe here a patient who developed VZV meningoencephalitis 2 years after human leukocyte antigen-matched unrelated HSCT for acute myeloblastic leukemia. She developed chronic graft-versus-host disease, and cyclosporine (CSA) was continued until 17 months after HSCT. Low-dose acyclovir (ACV) at 200 mg/day was administered to prevent the reactivation of VZV from day -7 to the termination of CSA. At 22 months, she suddenly developed fever, loss of consciousness, and seizure, with generalized skin rash. A high level of VZV DNA was detected in her cerebrospinal fluid (CSF). She was diagnosed to have VZV meningoencephalitis. Intravenous ACV at 30 mg/kg/day was given for 2 months. Although loss of consciousness was quickly resolved, some neurologic symptoms persisted. She did not have any known risk factors for VZV reactivation. Therefore, we should keep in mind that any HSCT recipient may develop VZV meningoencephalitis, and examination of CSF for VZV infection with an empiric administration of ACV may be recommended for HSCT recipients with central nervous system symptoms, even in the absence of skin manifestations.

[Medical care of AIDS patients by hospitals in Tokyo]

An anonymous questionnaire survey was performed in 1991 in all 749 hospitals in Tokyo, by the Tokyo Metropolitan Government's Acquired Immunodeficiency Syndrome (AIDS) and Human Immunodeficiency Virus (HIV) Infection Research Team, to collect information relating to hospital services for persons with AIDS or HIV infection. The response rate was 61%. The following results were obtained: 1) Sixty-five hospitals (14%) had seen persons with AIDS or HIV infection. Hospitals with a greater number of beds had more experience in seeing persons with AIDS or HIV infection. Thirty-four hospitals (7%) provided outpatient services for patients with AIDS or HIV infection, and 30 hospitals (7%) had the facilities for inpatients. Three hundred forty-seven hospitals (78%) were capable of HIV antibody tests. Ninety-one hospitals (20%) had organized training courses for hospital workers to prevent HIV infection. Two hundred eight hospitals (46%) expressed preference that persons with AIDS or HIV infection be treated at public (non-private) hospitals. 2) The results of multivariate logistic regression analysis indicated that a hospital's acceptance of persons with AIDS or HIV infection for diagnosis or treatment was significantly related to past experience in seeing persons with AIDS or HIV infection, availability of an examination room that protects privacy of patients, presence of a department of internal medicine, and awareness of the availability of special AIDS counselor dispatch services by the Tokyo metropolitan government.

Identification of a resin-dentin hybrid layer in vital human dentin created in vivo: durable bonding to vital dentin

The present study investigated the bond of 5% 4-methacryloxyethyl trimellitate anhydride in methyl methacrylate, initiated by partially oxidized tri-n-butyl borane in the presence of poly(methyl methacrylate) powder, to vital human dentin. In vivo dentinal substrates were pretreated for 10 or 30 seconds with an aqueous solution of 10% citric acid and 3% ferric chloride. Transmission electron microscopic examination of the bonded cross sections revealed the formation of a transitional, or "hybrid," layer of resin-reinforced dentin created by the impregnation, co-mingling and envelopment of collagen bundles, and encapsulation of hydroxylapatite crystals. The in vivo adhesion was assumed to be durable, because results of microscopic examinations were comparable to those of durable bonding of the same resin to extracted bovine dentin. Vital dentin exhibited greater resistance to demineralization by the acid solution than do extracted teeth. Carious extracted teeth were more easily dissolved in acid than were noncarious extracted teeth.

[Fifty-two-week oral chronic toxicity study of propiverine hydrochloride in rats]

An oral chronic toxicity study of propiverine hydrochloride (P-4), a new anti-pollakiuria agent, was carried out at dose levels of 0 (control), 0.5, 5 and 50 mg/kg/day using male and female rats. They were treated for 52 weeks, followed by 5 weeks recovery period. The results obtained from the present study were as follows. 1. There were no deaths related to P-4. Mydriasis, transitory salivation were observed in both sexes receiving 50 mg/kg/day, and soil of the abdomen was also noted in females receiving 50 mg/kg/day. 2. Body weight gain was suppressed from initiation of administration in both sexes receiving 50 mg/kg/day. 3. There were no significant or remarkable changes in food consumption, hematology and ophthalmology. 4. Urinary findings in animals receiving 50 mg/kg/day showed increases of urine and potassium excretion volumes and decrease of urine osmotic pressure in both sexes, negativity of urine protein and decrease of urobilinogen value in females. 5. Biochemical findings in animals receiving 50 mg/kg/day showed increase of urea-nitrogen (Urea N) in both sexes and decrease of triglyceride (TG), total cholesterol (T. cho), free cholesterol (F. cho), non-esterified fatty acids (NEFA) and phospholipid (PL) in males. 6. The absolute and/or relative weights of the liver increased in animals receiving 50 mg/kg/day. Histopathological examination in animals receiving 50 mg/kg/day revealed intranuclear eosinophilic inclusions and cytoplasmic eosinophilic substance in renal proximal tubular epithelium and midzonal lipid droplets in liver. Histochemical examination in animals receiving 50 mg/kg/day revealed the slight increase of gamma-GTP positive area in peripheral zone of liver. Electron-microscopic examination in animals receiving 50 mg/kg/day revealed intranuclear and intracellular large and homogeneous spherical-like structure with low electron density in renal proximal tubular epithelium, and slight hyperplasia of smooth endoplasmic reticulum with dilatation of cisternae and deposition of large lipid droplets in hepatocytes, but there was no difference of VLDL and its distributions in hepatocytes among groups.(ABSTRACT TRUNCATED AT 400 WORDS)

Notification of HIV carriers: possible effect on uptake of AIDS testing

Passing of the AIDS Prevention Bill, which demands the notification of human immunodeficiency virus (HIV) carriers, seems imminent in Japan. Its effect on people's willingness to be tested for the HIV antibody was assessed among heterosexual subjects (students, office workers) and groups at high risk of the acquired immunodeficiency syndrome (AIDS) (prostitutes, homosexual males) by means of a questionnaire. More than 70% of the 811 students and 509 workers replied that, if notification became mandatory, they would agree to be tested but 10% of the males and 17% of the females in these two groups would prefer testing at institutes not complying with the clause; all 198 prostitutes said that they would be prepared to undergo testing but 35% of them would prefer to go to non-complying clinics; 45% (410) of 902 homosexual males replied that they would refuse testing, and 65% of those who would agree to be tested (492) would prefer to go to non-complying clinics. These findings strongly suggest that when the bill is passed the greater the self-perceived risk of HIV infection the poorer will be the uptake of AIDS testing. Hence the bill would be counterproductive in the surveillance of potential HIV carriers.

Rheological studies of matrix--special reference on the mobility of leucocytes in relation to the rheological characters of experimental matrix

The rheological characteristics of a model matrix, consisting of Bacto-agar, were correlated with the ability of the matrix to permit cellular penetration, using a rheolometer and the agar bullet method. The most important rheologic characteristic that affected cellular mobility was found to be the viscosity rate. A viscosity rate under 1,000 X 10(4) dyne sec/cm2 was needed to permit cellular mobility.

The morphological changes in the sinusoid in bone marrow studied with administration of soluble immune complexes--structural changes of sinusoid in allergic process

The morphological changes of the sinusoidal endothelia in the bone marrow of a guinea pig have been studied with the administration of soluble immune complexes. There were noted sinusoidal distension with distinct endothelial and plasma stasis with a few blood cells.

Experimental osteomyelitis induced by repeated administration of soluble immune complexes: consideration of the fundamental pathogenesis of osteomyelitis

Morphological changes of blood vessel walls including various kinds of capillaries have been induced by administration of soluble immune complexes. After repeated administrations, those experimental animals who survived the phase of initial anaphylactic shock developed osteomyelitis. In this paper, the formative processes of osteomyelitis will be discussed in relation to Aschoff's definition of inflammation. We will emphasize the importance of the capillarization of the sinusoidal endothelia for the formation of osteomyelitis.