Keisuke Ishigami

Necessity of early intervention for IgG4-related disease—delayed treatment induces fibrosis progression

OBJECTIVE Despite ongoing research, the clinical and histopathological natural history of immunoglobulin (Ig) G4-related disease (IgG4-RD) remains unclear and the optimal time to initiate treatment is unknown. A focus on clinical symptoms rather than image finding is recommended for therapeutic initiation in autoimmune pancreatitis, but evidence for this approach is lacking. We aimed to retrospectively analyse disease duration, efficacy of treatment with glucocorticoids and results of histopathological examination of submandibular gland specimens to clarify the necessity for early intervention in IgG4-RD. METHODS Salivary secretions were assessed before and after treatment in 26 cases of IgG4-related Mikuliczs disease (IgG4-MD). Relationships between disease duration, amount of salivary secretion before treatment, improvement of salivary secretion and ratios of areas of residual acini, fibrosis and lymphoid follicles in the involved submandibular gland specimens were analysed. RESULTS Salivary secretions were significantly reduced in cases with illness of >2 years (P < 0.05). An inverse correlation was seen between improved amount of salivary secretion and amount of salivary secretion before treatment (r = -0.60). Improved amount of salivary secretion was also associated with each histological factor (acini, r = 0.29; fibrosis, r = -0.23; lymphoid follicles, r = -0.31), which showed interrelationships (acini and lymphoid follicles, r = -0.23; acini and fibrosis, r = 0.42; lymphoid follicles and fibrosis, r = 0.30). CONCLUSION Salivary secretion can be improved even in cases with lower levels of salivary secretion before treatment in IgG4-RD, but improvements in the amount of salivary secretion decrease with histological changes with delayed therapeutic intervention. These data suggest that early intervention is needed to improve outcomes in patients with IgG4-MD.

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.

Association of Fusobacterium nucleatum with immunity and molecular alterations in colorectal cancer

The human intestinal microbiome plays a major role in human health and diseases, including colorectal cancer. Colorectal carcinogenesis represents a heterogeneous process with a differing set of somatic molecular alterations, influenced by diet, environmental and microbial exposures, and host immunity. Fusobacterium species are part of the human oral and intestinal microbiota. Metagenomic analyses have shown an enrichment of Fusobacterium nucleatum (F. nucleatum) in colorectal carcinoma tissue. Using 511 colorectal carcinomas from Japanese patients, we assessed the presence of F. nucleatum. Our results showed that the frequency of F. nucleatum positivity in the Japanese colorectal cancer was 8.6% (44/511), which was lower than that in United States cohort studies (13%). Similar to the United States studies, F. nucleatum positivity in Japanese colorectal cancers was significantly associated with microsatellite instability (MSI)-high status. Regarding the immune response in colorectal cancer, high levels of infiltrating T-cell subsets (i.e., CD3+, CD8+, CD45RO+, and FOXP3+ cells) have been associated with better patient prognosis. There is also evidence to indicate that molecular features of colorectal cancer, especially MSI, influence T-cell-mediated adaptive immunity. Concerning the association between the gut microbiome and immunity, F. nucleatum has been shown to expand myeloid-derived immune cells, which inhibit T-cell proliferation and induce T-cell apoptosis in colorectal cancer. This finding indicates that F. nucleatum possesses immunosuppressive activities by inhibiting human T-cell responses. Certain microRNAs are induced during the macrophage inflammatory response and have the ability to regulate host-cell responses to pathogens. MicroRNA-21 increases the levels of IL-10 and prostaglandin E2, which suppress antitumor T-cell-mediated adaptive immunity through the inhibition of the antigen-presenting capacities of dendritic cells and T-cell proliferation in colorectal cancer cells. Thus, emerging evidence may provide insights for strategies to target microbiota, immune cells and tumor molecular alterations for colorectal cancer prevention and treatment. Further investigation is needed to clarify the association of Fusobacterium with T-cells and microRNA expressions in colorectal cancer.

Relapse patterns in IgG4-related disease

Immunoglobulin (Ig)G4-related disease (IgG4-RD) is a chronic inflammatory disorder characterised by elevated levels of serum IgG4 and swollen organs with fibrosis and infiltration by abundant IgG4-positive plasmacytes.1 ,2 Glucocorticoid treatment is effective for achieving clinical remission in the short term,3 but about 20%–30% of cases present with relapse after steroid doses are reduced.4 Serial changes of serum IgG4 levels are often considered to reflect the disease activity in routine clinical practice,5 but how disease relapse occurs is not well understood. We therefore analysed relapse patterns in IgG4-RD on the basis of data from the Sapporo Medical university And …

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 Mikuliczs 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.

Evaluation and Clinical Validity of a New Questionnaire for Mikulicz's Disease

Objectives. The characteristic features of Mikuliczs disease (MD) are diffuse enlargement of the lacrimal and submandibular glands, elevated levels of serum immunoglobulin (Ig)G4, and abundant infiltration of IgG4-positive plasmacytes into both glands. No disease index is available to properly evaluate MD, so we developed a functional assessment of MD, the Mikuliczs disease activity questionnaire (MAQ), and evaluated its clinical efficacy. Methods. We selected 18 patients who were either being treated for MD or who had presented with recurrence. The patients completed a self-assessment and were scored according to the MAQ sheet during each visit between December 2009 and August 2011. Assessment items were in regard to increases or decreases in lacrimal and salivary gland enlargement and severity of sicca symptoms. Results. On the first visits, MAQ scores were high, but scores decreased rapidly as treatment progressed. When doses of glucocorticoid were reduced, some patients showed increased scores. Dry-symptom scores increased initially. MAQ scores for patients with recurrent MD gradually increased over several months before relapse. However, some patients displayed no elevation in MAQ scores due to relapses at other sites. Conclusion. MAQ score can be used to quantify flares and treatment response and is useful for functional assessment of MD.

The relationship between EZH2 expression and microRNA-31 in colorectal cancer and the role in evolution of the serrated pathway.

Polycomb group protein enhancer of zeste homolog 2 (EZH2) is a methyltransferase that correlates with the regulation of invasion and metastasis and is overexpressed in human cancers such as colorectal cancer. MicroRNA-31 (miR-31) plays an oncogenic role and is associated with BRAF mutation and poor prognosis in colorectal cancer. EZH2 is functionally considered to suppress miR-31 expression in human cancers; however, no study has reported its relationship with colon cancer. We therefore evaluated EZH2 expression using immunohistochemistry and assessed miR-31 and epigenetic alterations using 301 colorectal carcinomas and 207 premalignant lesions. Functional analysis was performed to identify the association between EZH2 and miR-31 using cancer cell lines. In the current study, negative, weak, moderate, and strong EZH2 expressions were observed in 15%, 19%, 25%, and 41% of colorectal cancers, respectively. EZH2 was inversely associated with miR-31 (P < 0.0001), independent of clinicopathological and molecular features. In a multivariate stage-stratified analysis, high EZH2 expression was related to favorable prognosis (P = 0.0022). Regarding premalignant lesions, negative EZH2 expression was frequently detected in sessile serrated adenomas/polyps (SSA/Ps) (76%; P < 0.0001) compared with hyperplastic polyps, traditional serrated adenomas, and non-serrated adenomas (25–36%). Functional analysis demonstrated that the knockdown of EZH2 increased miR-31 expression. In conclusion, an inverse association was identified between EZH2 and miR-31 in colorectal cancers. Our data also showed that upregulation of EZH2 expression may be rare in SSA/Ps. These results suggest that EZH2 suppresses miR-31 in colorectal cancer and may correlate with differentiation and evolution of serrated pathway.

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

Abstract 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 (r2 = 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.

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.

The role of cytotoxic T cells in IgG4-related dacryoadenitis and sialadenitis, the so-called Mikulicz's disease.

Abstract Objectives. Immunoglobulin (Ig) G4-related dacryoadenitis and sialadenitis, the so-called Mikuliczs disease (MD), is a chronic inflammatory disease. However, little is known about its pathogenesis and pathological condition. In the present study, we used immunohistological techniques to compare the roles of cytotoxic T lymphocytes (CTLs) in MD and primary Sjogrens syndrome (SS). We examined the state of CTLs [cytotoxic granule-positive rate and programmed death-1 (PD-1) expression rate] in the salivary glands. Methods. The study samples comprised 12 submaxillary glands from untreated MD patients and 12 labial glands from SS patients. We performed immunofluorescence and multicolor immunofluorescence to stain CD8, perforin (PRF), granzyme B (GZMB), and PD-1. We measured the total number of CTLs as well as the PRF+CTLs, GZMB+CTLs, and PD-1+CTLs. Results. We found that the degree of infiltration of CTLs was equal in MD and SS, but the rate of CTLs with cytotoxic granules, especially PRF, in MD was less than in SS. In addition, the frequency of PD-1+CTLs in MD was higher than that in SS. Conclusions. Cytotoxic granule-positive CTLs were in the minority in MD salivary glands, and this regulation might relate to PD-1 signals like the state of exhaustion and anergy.