MicroRNA-196b is an independent prognostic biomarker in patients with pancreatic cancer.

Pancreatic cancer is a highly aggressive malignancy, with <50% patients surviving beyond 6 months after the diagnosis, and thus, there is an urgent need to explore new diagnostic and therapeutic approaches for this disease. Therefore, we conducted microRNA (miRNA) array analysis to detect miRNA molecules potentially associated with pancreatic cancer malignancy. To assess the identified miRNAs, we performed quantitative reverse transcription-PCR on 248 pancreatic ductal adenocarcinomas (UICC stage II). We also examined miRNA expression [microRNA-21 (miR-21) and microRNA-31 (miR-31)] and epigenetic alterations, including CpG island methylator phenotype (CIMP), potentially associated with the identified miRNAs. For functional analysis, we conducted proliferation and invasion assays using a pancreatic cancer cell line. miRNA array analysis revealed that microRNA-196b (miR-196b) was the most up-regulated miRNA in pancreatic cancer tissues compared with normal pancreatic duct cells. High miR-196b expression was associated with miR-21 (P = 0.0025) and miR-31 (P = 0.0001) expression. It was also related to poor prognosis in the multivariate analysis using overall survival (hazard ratio: 1.66; 95% confidence interval: 1.09-2.54; P = 0.019). Functional analysis demonstrated that miR-196b inhibitor decreased cell proliferation and that miR-196b mimic promoted cancer cell invasion. In conclusion, a significant association of high miR-196b expression with poor prognosis was observed in pancreatic cancer. Our data also revealed that miR-196b played an oncogenic role and that the transfection of the miR-196b inhibitor had an anti-tumour effect in the pancreatic cancer cell line. These results suggest that miR-196b is a promising diagnostic biomarker and therapeutic target in pancreatic cancer.

Establishment of a refined culture method for rat colon organoids.

BACKGROUND: Methods for the artificial three-dimensional (3D) culture of mouse and human small-intestinal and large-intestinal stem cells have been established with CD24+ or Paneth cell niches. In contrast, no studies have established stable 3D culture for rat colon stem cells. In this study, we established an advanced method for efficient rat colonic stem cell culture. METHODS: Using various tissue homogenates, we investigated the colonic organoid forming capacity under the TMDU protocol immediately adjacent to Ootani's 3D culture assembly in the same culture dish. Next, we examined whether the supernatant from the colon could be replaced by a colon homogenate. Finally, we identified the bioactive substances that were indispensable for efficient organoid culture using protein purification by three-step column chromatography and proteomic analysis with a quantitative nanoflow liquid chromatography-tandem mass spectrometry (LC-MS/MS). RESULTS: By combining Ootani's method with the TMDU protocol, we established a refined culture method for Lewis rat colon organoids, which we refer to as the modified TMDU protocol. Furthermore, we confirmed that PGE2 and galection-4 promoted rat colonic organoid formation. CONCLUSIONS: We established efficient rat colonic stem cell cultures in vitro. This success will contribute to the study of rat intestinal-disease models.

The effect of forced expression of mutated K-RAS gene on gastrointestinal cancer cell lines and the IGF-1R targeting therapy.

Mutation in K-RAS (K-RAS-MT) plays important roles in both cancer progression and resistance to anti-epidermal growth factor receptor (EGFR) therapy in gastrointestinal tumors. Insulin-like growth factor-1 receptor (IGF-1R) signaling is required for carcinogenicity and progression of many tumors as well. We have previously shown successful therapy for gastrointestinal cancer cell lines bearing a K-RAS mutation using an anti-IGF-1R monoclonal antibody. In this study, we sought to evaluate effects of forced K-RAS-MT expression on gastrointestinal cancer cell lines representing a possible second resistance mechanism for anti-EGFR therapy and IGF-1R-targeted therapy for these transfectants. We made stable transfectants of K-RAS-MT in two gastrointestinal cancer cell lines, colorectal RKO and pancreatic BxPC-3. We assessed the effect of forced expression of K-RAS-MT on proliferation, apoptosis, migration, and invasion in gastrointestinal cancer cells. Then we assessed anti-tumor effects of dominant negative IGF-1R (IGF-1R/dn) and an IGF-1R inhibitor, picropodophyllin, on the K-RAS-MT transfectants. Overexpression of K-RAS-MT in gastrointestinal cancer cell lines led to more aggressive phenotypes, with increased proliferation, decreased apoptosis, and increased motility and invasion. IGF-1R blockade suppressed cell growth, colony formation, migration, and invasion, and up-regulated chemotherapy-induced apoptosis of gastrointestinal cancer cells, even when K-RAS-MT was over-expressed. IGF-1R blockade inhibited the Akt pathway more than the extracellular signal-regulated kinase (ERK) pathway in the K-RAS-MT transfectants. IGF-1R/dn, moreover, inhibited the growth of murine xenografts expressing K-RAS-MT. Thus, K-RAS-MT might be important for progressive phonotype observed in gastrointestinal cancers. IGF-1R decoy is a candidate molecular therapeutic approach for gastrointestinal cancers even if K-RAS is mutated. © 2016 Wiley Periodicals, Inc.

Heat shock protein 90 associates with Toll-like receptors 7/9 and mediates self-nucleic acid recognition in SLE.

Systemic lupus erythematosus (SLE) is a prototype systemic autoimmune disease, and disease activity is associated with serum IFN-α level. Plasmacytoid dendritic cells (pDCs) sense microbial as well as self-nucleic acids by TLRs 7 and 9 and produce a large amount of IFN-α. Here, we show that heat shock protein 90 (Hsp90) associates with and delivers TLR7/9 from the ER to early endosomes for ligand recognition. Inhibition of Hsp90 by various approaches including the use of Hsp90 inhibitor, a geldanamycin derivative, suppressed the Hsp90 association with TLR7/9, which resulted in inhibition of IFN-α production, leading to improvement of SLE symptoms in mice. Notably, we observed that serum Hsp90 is clearly increased in patients with active SLE compared with that in patients with inactive disease. Furthermore, we demonstrated that serum Hsp90 detected in SLE patients binds to self-DNA and/or anti-DNA Ab, thus leading to stimulation of pDCs to produce IFN-α. Our data demonstrate that Hsp90 plays a crucial role in the pathogenesis of SLE and that an Hsp90 inhibitor will therefore provide a new therapeutic approach to SLE and other nucleic acid-related autoimmune diseases.

Loss of interleukin-21 leads to atrophic germinal centers in multicentric Castleman's disease.

Both multicentric Castleman's disease (MCD) and immunoglobulin (Ig)G4-related disease (IgG4-RD) are systemic diseases, presenting with hypergammaglobulinemia and elevated serum levels of IgG4. However, with regard to histopathological findings, MCD shows atrophic germinal centers. On the other hand, expanded germinal centers are detected in IgG4-RD. We extracted germinal centers from specimens of each disorder by microdissection and analyzed the expression of mRNAs by real-time polymerase chain reaction to clarify the mechanisms underlying atrophied germinal centers in MCD. This analysis disclosed loss of interleukin (IL)-21 and B cell lymphoma (Bcl)-6 in the germinal centers of MCD. Loss of IL-21 is considered to be involved in the disappearance of Bcl-6 and leads to atrophied germinal centers in MCD.

Serum HER2 as an adjunct to assess HER2 status for advanced gastric cancer: A prospective multicenter trial (SHERLOCK).

BACKGROUND: Intratumoral human epidermal growth factor receptor 2 (HER2) heterogeneity of gastric cancer can be an obstacle to accurate HER2 assessment. Serum HER2, concentrations of the HER2 extracellular domain shed into the bloodstream, has a potential to compensate HER2 immunohistochemistry (IHC) but has not been scrutinized in gastric cancer. This study sought to explore the clinical utility of serum HER2 in gastric cancer. METHODS: We performed a prospective multicenter trial (SHERLOCK trial) involving patients with all-stage gastric or gastro-esophageal junction cancer. Serum HER2 was measured using direct chemiluminescence while tissue HER2 status was determined using IHC and fluorescent in situ hybridization. For stage IV cases, concordance between local and central laboratories in tissue HER2 assessment was also evaluated. RESULTS: Of 224 patients enrolled, both tissue HER2 status and serum HER2 levels were successfully determined in 212 patients and 21% (45/212) were tissue HER2-positive. Serum HER2 levels, ranged from 4.5 to 148.0 ng/ml (median 10.3), correlated with tissue HER2 status (p = 0.003). At a cut-off level of 28.0 ng/ml determined by receiver operating characteristics analysis, sensitivity, specificity, positive and negative predictive values of serum HER2 were 22.6%, 100%, 100% and 82.3%, respectively. All nine cases with elevated serum HER2 were tissue HER2-positive stage IV cases. Among 61 stage IV cases, the agreement rate for IHC scoring between the local and the central laboratories was 82% and tissue HER2 judgment was conflicting in five (8.2%) cases. Of these five cases, four were confirmed as false-negative and two of these four patients demonstrated elevated serum HER2. CONCLUSIONS: Serum HER2 levels correlated with tissue HER2 status in gastric cancer. Although the low sensitivity is a drawback, serum HER2 might be a useful adjunct tool to detect tissue HER2 false-negative gastric cancer.

Role of interleukin-32 in the mechanism of chronic inflammation in IgG4-related disease and as a predictive biomarker for drug-free remission.

OBJECTIVES: In immunoglobulin (Ig) G4-related disease (IgG4-RD), the mechanism of chronic inflammation and predictive factors for drug-free remission is still unclear. To examine the issues, we focused on tuberculosis, a chronic infection, and on the role of interleukin (IL)-32. METHODS: We examined the positive rate of QuantiFERON TB-2G (QFT-2G) in 126 patients with IgG4-RD, and compared with the rate in the general population. Furthermore, specimens of submandibular glands from the maintenance treatment group and drug-free group of IgG4-RD and specimens of small salivary glands from primary Sjögren's syndrome (SS) were stained with anti-IL-32 antibody and anti-protease-activated receptor 2 antibody, and the number of positive cells was compared between these groups. RESULTS: The positive rate of QFT-2G was 19.8% in IgG4-RD patients, which is higher than in the general population. The expression of IL-32 and PAR2 in the submandibular glands of the maintenance treatment group of IgG4-RD was significantly greater than that of the drug-free remission group and SS patients. CONCLUSIONS: This study indicates the possibility that IL-32 is associated with chronic inflammation and that it can be a predictive factor for drug-free remission in IgG4-RD.

A case of angioimmunoblastic T-cell lymphoma with high serum VEGF preceded by RS3PE syndrome.

We report the case of a 76-year-old man diagnosed with angioimmunoblastic T-cell lymphoma (AITL) with high serum vascular endothelial growth factor (VEGF) preceded by Remitting seronegative symmetrical synovitis with pitting edema syndrome. He suffered respiratory discomfort caused by large amounts of pleural effusion. Interestingly, changes in serum VEGF measured over time were similar to changes in pleural effusion. Whether VEGF is related to the pathological condition of AITL is a very important question.

Association of Fusobacterium nucleatum with clinical and molecular features in colorectal serrated pathway.

Human gut microbiota is being increasingly recognized as a player in colorectal cancers (CRCs). Evidence suggests that Fusobacterium nucleatum (F. nucleatum) may contribute to disease progression and is associated with CpG island methylator phenotype (CIMP) and microsatellite instability (MSI) in CRCs; however, to date, there are no reports about the relationship between F. nucleatum and molecular features in the early stage of colorectal tumorigenesis. Therefore, we investigated the presence of F. nucleatum in premalignant colorectal lesions. In total, 465 premalignant lesions (343 serrated lesions and 122 non-serrated adenomas) and 511 CRCs were studied. We determined the presence of F. nucleatum and analyzed its association with molecular features including CIMP, MSI and microRNA-31 status. F. nucleatum was detected in 24% of hyperplastic polyps, 35% of sessile serrated adenomas (SSAs), 30% of traditional serrated adenomas (TSAs) and 33% of non-serrated adenomas. F. nucleatum was more frequently detected in CIMP-high premalignant lesions than in CIMP-low/zero lesions (p = 0.0023). In SSAs, F. nucleatum positivity increased gradually from sigmoid colon to cecum (p = 0.042). F. nucleatum positivity was significantly higher in CRCs (56%) than in premalignant lesions of any histological type (p < 0.0001). In conclusion, F. nucleatum was identified in premalignant colorectal lesions regardless of histopathology but was more frequently associated with CIMP-high lesions. Moreover, F. nucleatum positivity increased according to histological grade, suggesting that it may contribute to the progression of colorectal neoplasia. Our data also indicate that F. nucleatum positivity in SSAs may support the "colorectal continuum" concept.

Identification of relapse predictors in IgG4-related disease using multivariate analysis of clinical data at the first visit and initial treatment.

OBJECTIVES: Inducting clinical remission by glucocorticoid treatment is relatively easy in IgG4-related disease (IgG4-RD), but relapse also occurs easily with tapering of the steroid dose. The present study tried to analyse the cases to extract predictors of relapse present at the diagnosis of IgG4-RD. METHODS: Subjects comprised 79 patients with IgG4-related dacryoadenitis and sialadenitis, known as Mikulicz's disease, who were diagnosed between April 1997 and October 2013 and followed-up for >2 years from the initial induction treatment. They were applied to Cox proportional hazard modelling, based on the outcome of interval to relapse. We performed multivariate analysis for the clinical factors of these cases and identified predictors of relapse. RESULTS: Identified factors were male sex and younger onset in cases without organ involvement at diagnosis and low levels of serum IgG4 in cases with organ dysfunction at diagnosis. Complication with autoimmune pancreatitis and low steroid dose at initial treatment also tended to be associated with recurrence. CONCLUSION: Follow-up is important in cases with recognized risk factors for relapse, including male sex and younger onset in cases without organ damage.

Association of MicroRNA-31-5p with Clinical Efficacy of Anti-EGFR Therapy in Patients with Metastatic Colorectal Cancer.

BACKGROUND: Gene mutations in the pathway downstream of epidermal growth factor receptor (EGFR) are considered to induce resistance to anti-EGFR therapy in colorectal cancer (CRC). We recently reported that microRNA-31 (miR-31)-5p may regulate BRAF activation and play a role in the signaling pathway downstream of EGFR in CRC. Therefore, we hypothesized that miR-31-5p can be a useful biomarker for anti-EGFR therapy in CRC. METHODS: We evaluated miR-31-5p expression and gene mutations [KRAS (codon 61 or 146), NRAS (codon 12, 13, or 61), and BRAF (V600E)] in the EGFR downstream pathway in 102 CRC patients harboring KRAS (codon 12 or 13) wild-type who were treated with anti-EGFR therapeutics. Progression-free survival (PFS) and overall survival (OS) were evaluated. RESULTS: KRAS (codon 61 or 146), NRAS, and BRAF mutations were detected in 6.9, 6.9, and 5.9 % patients, respectively. Compared with CRCs with at least one mutation (n = 20), significantly better PFS (P = 0.0003) but insignificantly better OS were observed in CRCs harboring all wild-type genes (KRAS, NRAS, and BRAF). High miR-31-5p expression was identified in 11 % (n = 11) patients and was significantly associated with shorter PFS (P = 0.003). In CRCs carrying all wild-type genes, high miR-31-5p was associated with shorter PFS (P = 0.027). CONCLUSIONS: High miR-31-5p expression was associated with shorter PFS in patients with CRC treated with anti-EGFR therapeutics. Moreover, in CRCs carrying all wild-type genes, high miR-31-5p was associated with shorter PFS, suggesting that it may be a useful and additional prognostic biomarker for anti-EGFR therapy.

Mesenchymal stem cells cancel azoxymethane-induced tumor initiation.

The role of mesenchymal stem cells (MSCs) in tumorigenesis remains controversial. Therefore, our goal was to determine whether exogenous MSCs possess intrinsic antineoplastic or proneoplastic properties in azoxymethane (AOM)-induced carcinogenesis. Three in vivo models were studied: an AOM/dextran sulfate sodium colitis-associated carcinoma model, an aberrant crypt foci model, and a model to assess the acute apoptotic response of a genotoxic carcinogen (AARGC). We also performed in vitro coculture experiments. As a result, we found that MSCs partially canceled AOM-induced tumor initiation but not tumor promotion. Moreover, MSCs inhibited the AARGC in colonic epithelial cells because of the removal of O(6)-methylguanine (O(6) MeG) adducts through O(6) MeG-DNA methyltransferase activation. Furthermore, MSCs broadly affected the cell-cycle machinery, potentially leading to G1 arrest in vivo. Coculture of IEC-6 rat intestinal cells with MSCs not only arrested the cell cycle at the G1 phase, but also induced apoptosis. The anti-carcinogenetic properties of MSCs in vitro required transforming growth factor (TGF)-ß signaling because such properties were completely abrogated by absorption of TGF-ß under indirect coculture conditions. MSCs inhibited AOM-induced tumor initiation by preventing the initiating cells from sustaining DNA insults and subsequently inducing G1 arrest in the initiated cells that escaped from the AARGC. Furthermore, tumor initiation perturbed by MSCs might potentially dysregulate WNT and TGF-ß-Smad signaling pathways in subsequent tumorigenesis. Obtaining a better understanding of MSC functions in colon carcinogenesis is essential before commencing the broader clinical application of promising MSC-based therapies for cancer-prone patients with inflammatory bowel disease.

A randomized controlled trial of endoscopic steroid injection for prophylaxis of esophageal stenoses after extensive endoscopic submucosal dissection.

BACKGROUND: Esophageal stenosis following endoscopic submucosal dissection (ESD) is a serious adverse event that makes subsequent management more difficult. METHODS: This parallel, randomized, controlled, open-label study was designed to examine whether local steroid injection is an effective prophylactic treatment for esophageal stenoses following extensive ESD. This single center trial was conducted at the Keiyukai Hospital, a tertiary care center for gastrointestinal disease in Japan [University Hospital Medical Network Clinical Trial Registry (UMIN-CTR) on 15 September 2011 (UMIN000006327)]. Thirty-two patients with mucosal defects involving ≥75% of the esophageal circumference were randomized to receive a single dose of triamcinolone acetonide injections (n = 16) or be treated conventionally (n = 16). The primary outcome was the frequency of stricture requiring endoscopic dilatation; the surrogate primary endpoint was the number of dilatation sessions needed. Secondary outcomes included adverse event rates, the minimum diameter of the stenotic area and the duration of the course of dilatation treatments. RESULTS: The frequency of stricture was not significantly different between the groups because of insufficient statistical power, but the number of dilatation sessions required was significantly less in the steroid group (6.1 sessions [95% confidence interval, CI 2.8-9.4] versus 12.5 [95% CI 7.1-17.9] sessions in the control group; P = 0.04). The perforation rate was similar in both groups. The minimum diameter of stenotic lumens was significantly greater in the treatment group than controls (11.0 mm versus 7.1 mm, respectively; P = 0.01). The perforation rate was not significantly different between the groups (1.0% versus 0.5% in the treatment and control group, respectively). Steroid injection was effective in cases of mucosal defects encompassing the entire esophageal circumference. CONCLUSIONS: Prophylactic endoscopic steroid injection appears to be a safe means of relieving the severity of esophageal stenoses following extensive ESD.

Clinicopathological and molecular characteristics of serrated lesions in Japanese elderly patients.

BACKGROUND: The population in Japan is aging more rapidly than in any other country. However, no studies have determined the characteristics of the large population of elderly patients with colorectal tumors. Therefore, we examined the clinicopathological and molecular features of these tumors in elderly patients. METHODS: In total, 1,627 colorectal tumors (393 serrated lesions, 277 non-serrated adenomas and 957 colorectal cancers) were acquired from patients. Tumor specimens were analyzed for BRAF and KRAS mutations, CpG island methylator phenotype-specific promoters (CACNA1G, CDKN2A, IGF2 and RUNX3), IGFBP7, MGMT, MLH1 and RASSF2 methylation, microsatellite instability (MSI) and microRNA- 31 (miR-31). RESULTS: The frequency of elderly patients (aged ≥75 years) with sessile serrated adenomas (SSAs) with cytological dysplasia was higher than that of those with other serrated lesions and non-serrated adenomas (p < 0.0001). In elderly patients, all SSAs were located in the proximal colon (particularly the cecum to ascending colon). High miR-31 expression, MLH1 methylation and MSI-high status were more frequently detected in SSAs from elderly patients than in those from non-elderly patients. In contrast, no significant differences were found between older age of onset and high-grade dysplasia for traditional serrated adenomas or non-serrated adenomas in any of these molecular alterations. CONCLUSION: In elderly patients, all SSAs were located in the proximal colon. Furthermore, cytological dysplasia and molecular alterations were more frequently detected in elderly patients with SSAs than in non-elderly patients. Thus, careful colonoscopic examinations of the proximal colon are necessary for elderly patients because SSAs in those patients may exhibit malignant potential.

Development of hypertension within 2 weeks of initiation of sorafenib for advanced hepatocellular carcinoma is a predictor of efficacy.

BACKGROUND: Sorafenib is an agent that inhibits vascular endothelial growth factor and is associated with onset or worsening of hypertension in some patients. We conducted a retrospective analysis of whether the development of hypertension during sorafenib treatment of advanced hepatocellular carcinoma could be a predictor of anti-cancer efficacy. METHODS: The study included 38 patients with advanced hepatocellular carcinoma who had received sorafenib for at least 1 month between January 2010 and December 2012. A retrospective analysis of the efficacy of sorafenib was conducted by dividing the patients into two groups-a hypertension group, presenting with grade 2 or higher hypertension according to the Common Terminology Criteria for Adverse Events (CTCTE) version 4.0; and a non-hypertension group, which included all other patients. This study evaluated the occurrence of hypertension within 2 weeks of initiation of therapy in order to avoid any treatment duration bias. Images were evaluated using the modified Response Evaluation Criteria in Solid Tumors. The response rate, time to progression, and overall survival were assessed. RESULTS: Twenty-two patients (58 %) developed grade 2 or higher hypertension within 2 weeks of initiation of therapy. The response rate was significantly higher in the hypertension group. Median time to progression was 153 days in the hypertension group versus 50.5 days in the non-hypertension group, which was significantly longer in the hypertension group. Moreover, median overall survival was 1,329 days in the hypertension group versus 302 days in the non-hypertension group, which was significantly longer in the hypertension group. CONCLUSIONS: Hypertension within 2 weeks of initiation of therapy may be a predictor of the anti-cancer efficacy of sorafenib when used for the treatment of advanced hepatocellular carcinoma.

CCAAT/enhancer binding protein α (C/EBPα)(+) M2 macrophages contribute to fibrosis in IgG4-related disease?

IgG4-related disease (IgG4-RD) is a new disease entity characterized by type 2 helper T (Th2)-dominant inflammation and progressive fibrosis. We found the infiltration of strange cell populations in the fibrotic lesions of submandibular gland specimens obtained from 15 patients with IgG4-RD. These cells expressed CCAAT/enhancer binding protein a (C/EBPα). Many of the cell populations were identified with M2 macrophages. The degrees of infiltration of C/EBPα(+)M2 macrophages and the ratio of fibrotic lesions in the specimens were correlated (r(2) = 0.83, p < 0.01). We also analyzed the expression of C/EBPα in other chronic inflammatory disorders: synovium in rheumatoid arthritis (RA), liver tissue in chronic viral hepatitis, and mucosa in ulcerative colitis. The specimens from RA and chronic viral hepatitis showed infiltration of C/EBPα(+) cells, but there were few C/EBPα-positive cells in ulcerative colitis. Fibrosis is not a major issue in ulcerative colitis. In conclusion, we found the remarkable infiltration of C/EBPα(+)M2 macrophages in cases of chronic inflammation with fibrosis, including IgG4-RD. This primitive study also disclosed that most of C/EBPα(+)M2 macrophages localized in fibrotic lesions, and the degree of the infiltration and the ratio of fibrotic area were correlated.

Everyday clinical practice in IgG4-related dacryoadenitis and/or sialadenitis: results from the SMART database.

Abstract Objective. Immunoglobulin (Ig)G4-related disease (IgG4-RD) is a new disease entity that has only been identified this century. Clinical information is thus lacking. We established the Sapporo Medical University and Related Institutes Database for Investigation and Best Treatments of IgG4-related Disease (SMART) to clarify the clinical features of IgG4-RD and provide useful information for clinicians. Methods. Participants comprised 122 patients with IgG4-related dacryoadenitis and/or sialadenitis (IgG4-DS), representing lacrimal and/or salivary lesions of IgG4-RD, followed-up in December 2013. We analyzed the sex ratio, mean age at onset, organ dysfunction, history or complications of malignancy, treatments, rate of clinical remission, and relapse. Results. The sex ratio was roughly equal. Mean age at diagnosis was 59.0 years. Positron emission tomography revealed that the ratio of other organ involvements was 61.4%. Complications of malignancy were observed in 7.4% of cases. Glucocorticoid was used to treat 92.1% of cases, and the mean maintenance dose of prednisolone was 4.8 mg/day. Rituximab was added in three cases, and showed good steroid-sparing effect. The clinical remission rate was 73.8%, and the annual relapse rate was 11.5%. Half of the cases experienced relapses within 7 years of initial treatment. Conclusion. We analyzed the clinical features and treatments of IgG4-DS using SMART, providing useful information for everyday clinical practice.

[A case of primary mediastinal (Thymic) B-cell lymphoma successfully treated with the DA-EPOCH-R Regimen].

Primary mediastinal (thymic) B-cell lymphoma (PMBL) is resistant to treatment when compared with diffuse large B-cell lymphoma (DLBCL). Moreover, the optimal first -line treatment of PMBL has not yet been determined. Herein, we report a case of PMBL that was successfully treated with the dose adjusted (DA) etoposide, prednisolone, vincristine, doxorubicin, and cyclophosphamide with rituximab (EPOCH-R) regimen. A-29-year-old woman was referred to our hospital with an anterior mediastinal tumor. Eight months before admission, she had visited a clinic for pain in the chest and back, but no abnormalities were found. Subsequently, her chest pain got worse, and she went to another clinic, where she was detected with an anterior mediastinal tumor and was referred to our hospital. Tumor biopsy with a thoracoscope was performed, and a diagnosis of PMBL was made. The tumor diameter was 90 mm, with invasion to the lungs and superior vena cava. The tumor had a clinical stage of IEA, and the International Prognostic Index (IPI) was low risk. She was treated with the DA-EPOCH-R regimen for 8 courses, and a complete response was achieved. A recent retrospective study of DA-EPOCH-R treatment without radiotherapy for PMBL was recently published. It showed that the event-free survival rate was 93% and the overall survival rate was 97% during a median 5-year follow-up. Thus, DA-EPOCH-R may be a potential standard treatment for PMBL.

Association of microRNA-31 with BRAF mutation, colorectal cancer survival and serrated pathway.

BRAF is an important gene in colorectal cancers (CRCs) that is associated with molecular characterization and resistance to targeted therapy. Although microRNAs (miRNAs) are useful biomarkers of various cancers, the association between miRNA and BRAF in CRCs is undefined. Therefore, this study was conducted to identify a relationship between specific miRNA molecules and BRAF mutation in CRCs and serrated lesions. miRNA array was used for the measurement of 760 miRNAs in 29 CRCs. To assess the identified miRNAs, quantitative reverse transcription-PCR was performed on 721 CRCs, 381 serrated lesions and 251 non-serrated adenomas. Moreover, proliferation and invasion assays were conducted using cell lines. miRNA array analysis revealed that microRNA-31 (miR-31)-5p was the most up-regulated miRNA in CRCs with mutated BRAF (V600E) compared with CRCs possessing wild-type BRAF (including cases with KRAS mutation). High miR-31 expression was associated with BRAF and KRAS mutations and proximal location (P < 0.0001). High miR-31 expression was related to cancer-specific mortality [multivariate hazard ratio = 2.06, 95% confidence interval: 1.36-3.09, P = 0.0008]. Functional analysis demonstrated that miR-31 inhibitor decreased cell invasion and proliferation. With regard to serrated lesions, high miR-31 expression was less frequently detected in hyperplastic polyps compared with other serrated lesions. In conclusion, associations were identified between miR-31, BRAF and prognosis in CRC. Transfection of miR-31 inhibitor had an antitumour effect. Thus, miR-31 may be a promising diagnostic biomarker and therapeutic target in colon cancers. Moreover, high miR-31 expression in serrated lesions suggested that miR-31 may be a key molecule in serrated pathway.

MicroRNA-31 expression in relation to BRAF mutation, CpG island methylation and colorectal continuum in serrated lesions.

The CpG island methylator phenotype (CIMP) is a distinct form of epigenomic instability. Many CIMP-high colorectal cancers (CRCs) with BRAF mutation are considered to arise from serrated pathway. We recently reported that microRNA-31 (miR-31) is associated with BRAF mutation in colorectal tumors. Emerging new approaches have revealed gradual changes in BRAF mutation and CIMP-high throughout the colorectum in CRCs. Here, we attempted to identify a possible association between miR-31 and epigenetic features in serrated pathway, and hypothesized that miR-31 supports the "colorectal continuum" concept. We evaluated miR-31 expression, BRAF mutation and epigenetic features including CIMP status in 381 serrated lesions and 222 non-serrated adenomas and examined associations between them and tumor location (rectum; sigmoid, descending, transverse and ascending colon and cecum). A significant association was observed between high miR-31 expression and CIMP-high status in serrated lesions with BRAF mutation (p = 0.0001). In contrast, miR-31 was slightly but insignificantly associated with CIMP status in the cases with wild-type BRAF. miR-31 expression in sessile serrated adenomas (SSAs) with cytological dysplasia was higher than that in SSAs, whereas, no significant difference was observed between traditional serrated adenomas (TSAs) and TSAs with high-grade dysplasia. The frequency of miR-31, BRAF mutation CIMP-high and MLH1 methylation increased gradually from the rectum to cecum in serrated lesions. In conclusion, miR-31 expression was associated with CIMP-high status in serrated lesions with BRAF mutation. Our data also suggested that miR-31 plays an important role in SSA evolution and may be a molecule supporting the colorectal continuum.