Solid‐type poorly differentiated adenocarcinoma of the stomach: Deficiency of mismatch repair and SWI/SNF complex

ARID1A, one of the subunits in SWI/SNF chromatin remodeling complex, is frequently mutated in gastric cancers with microsatellite instability (MSI). The most frequent MSI in solid‐type poorly differentiated adenocarcinoma (PDA) has been reported, but the SWI/SNF complex status in solid‐type PDA is still largely unknown. We retrospectively analyzed 54 cases of solid‐type PDA for the expressions of mismatch repair (MMR) proteins (MLH1, PMS2, MSH2, and MSH6), SWI/SNF complex subunits (ARID1A, INI1, BRG1, BRM, BAF155, and BAF170) and EBER, and mutations in KRAS and BRAF. We analyzed 40 cases of another histological type of gastric cancer as a control group. The solid‐type PDAs showed coexisting glandular components (76%), MMR deficiency (39%), and complete/partial loss of ARID1A (31%/7%), INI1 (4%/4%), BRG1 (48%/30%), BRM (33%/33%), BAF155 (13%/41%), and BAF170 (6%/2%), EBER positivity (4%), KRAS mutation (2%), and BRAF mutation (2%). Compared to the control group, MMR deficiency and losses of ARID1A, BRG1, BRM, and BAF155 were significantly frequent in solid‐type PDAs. Mismatch repair deficiency was associated with the losses of ARID1A, BRG1, and BAF155 in solid‐type PDAs. In the MMR‐deficient group, solid components showed significantly more frequent losses of ARID1A, BRG1, BRM, and BAF155 compared to glandular components (P = .0268, P = .0181, P = .0224, and P = .0071, respectively). In the MMR‐proficient group, solid components showed significantly more frequent loss of BRG1 compared to glandular components (P = .012). In conclusion, solid‐type PDAs showed frequent losses of MMR proteins and the SWI/SNF complex. We suggest that loss of the SWI/SNF complex could induce a morphological shift from differentiated‐type adenocarcinoma to solid‐type PDA.     

Sustainability and switching of biologics for psoriasis and psoriatic arthritis at Fukuoka University Psoriasis Registry

Biologics are efficacious for treating psoriasis vulgaris (PsV) and psoriatic arthritis (PsA), but sometimes must be terminated or changed for various reasons including ineffectiveness or adverse events. To find the optimal choice of biologics for treating psoriasis, we analyzed the real‐world data on drug survival and the reason for terminating or switching biologics. Medical records from patients with PsV or PsA, who visited the Department of Dermatology, Fukuoka University Hospital from 2010 to 2017, were analyzed. Two hundred and eleven patients received biologics, and 147 patients (69.7%) were treated with only one biologic, while 64 patients (30.3%) were switched to different products. Frequently used biologics in PsV were ustekinumab (UST), infliximab and adalimumab when calculated by patient‐year. Tumor necrosis factor inhibitor (TNFi) use decreased while UST and interleukin (IL)‐17 inhibitors increased in newly introduced patients. UST showed the highest survival rate as a first‐line drug, but the advantage was lost in the second reagent's group. The major reasons for terminating/switching biologics were as follows: primary ineffectiveness (26.4%), secondary loss of efficacy (36.5%), patient's preference, including referral to nearby hospital, or stopped visiting (22.6%), side‐effects (7.7%), comorbidities (3.4%) and economic burden (2.4%). In PsA patients, TNFi are more frequently employed than in PsV patients, although switching to UST or IL‐17 inhibitors showed an increasing trend. Biologic reagents were changed mostly because of primary or secondary loss of efficacy, which affected drug survival. Further research is needed to find the optimal choice of biologics with larger samples at multiple facilities.     

Rituximab therapy is more effective than cyclophosphamide therapy for Japanese patients with anti‐topoisomerase I‐positive systemic sclerosis‐associated interstitial lung disease

Systemic sclerosis‐associated interstitial lung disease (SSc‐ILD) is the most frequent cause of death for SSc but there is still no sufficient treatment available. Although cyclophosphamide (CYC) therapy is a common treatment which has shown statistical efficacy against SSc‐ILD to date, its effects are temporary and not enough. Rituximab (RTX), the anti‐CD20 monoclonal antibody, has recently shown efficacy in many autoimmune diseases. In SSc‐ILD, RTX is also considered to be one of the novel treatment candidates. However, studies of SSc‐ILD in Japanese treated with RTX have only a few case reports. Therefore, in this study, we retrospectively compared nine patients treated with RTX and 30 patients treated with CYC to investigate the efficacy of RTX treatment for Japanese anti‐topoisomerase I‐positive SSc‐ILD patients. At the 24‐month evaluation, the improvement rates of percent predicted of forced vital capacity and percent predicted of diffusing capacity of the lung carbon monoxide in the RTX‐treated group were significantly higher than those in the CYC‐treated group (20.6 ± 8.8% vs 1.1 ± 3.9%; P < 0.05 and 34.0 ± 6.0% vs ?1.5 ± 2.8%; P < 0.01, respectively). In addition, skin thickness scores also showed a marked improvement from 13.5 points before the start of treatment to 5.8 points after 24 months by RTX therapy (P < 0.05). These results suggest that RTX treatment is more effective for Japanese SSc‐ILD patients than CYC treatment. In the future, it is expected that large‐scale clinical trials will show the usefulness of RTX treatment for SSc‐ILD.     

Coffin-Siris syndrome with bilateral macular dysplasia caused by a novel exonic deletion in ARID1B

Coffin-Siris syndrome (CSS) is a congenital anomaly syndrome characterized by developmental delay, coarse facial features, and hypoplasia of the fifth digit's nail or phalanges. Herein, we report a case of the 8-year-old female patient who showed developmental delay associated with dysplasia in the macular and large toe area. Comprehensive genomic analysis showed no possible candidate variants, but the subsequent genomic copy number analysis revealed a novel exonic deletion in the coding region of AT-rich interactive domain-containing protein 1B (ARID1B), a gene responsible for CSS. Genomic copy number analysis can aid in diagnosing CSS by confirming undiagnosed exonic deletions in ARID1B. Furthermore, this is the first report of CSS associated with bilateral macular dysplasia.     

Percentage of residual B cells after 2 weeks of rituximab treatment predicts the improvement of systemic sclerosis-associated interstitial lung disease

The benefit of rituximab (RTX) for systemic sclerosis-associated interstitial lung disease (SSc-ILD) has been shown in previous clinical trials. However, predictors of RTX efficacy have not been clarified. We investigated whether B-cell responsiveness to RTX is related to therapeutic effect. Ten SSc-ILD patients treated with RTX in an independent clinical trial (Japan Registry of Clinical Trials, jRCTs031180373) were included in this analysis. Peripheral B-cell counts were examined retrospectively before RTX administration (baseline) and at 2, 4, 12, and 24 weeks after the first RTX administration, along with percent-predicted forced vital capacity (%FVC) before and 24 weeks after RTX treatment. Relative to baseline, the percentage of residual peripheral blood B cells at 2 weeks after RTX was negatively correlated with the %FVC improvement at the 24-week assessment (r = ?0.41, p = 0.04). In the subgroup with less than 5% B-cell persistence at week 2, %FVC at the 24-week assessment was significantly improved compared to baseline (p = 0.02). In another subgroup with more than 5% residual B cells, %FVC was not significantly different after 24 weeks compared to baseline (p = 0.41). In conclusion, the removal rate of B cells after 2 weeks of RTX treatment may be a useful surrogate marker of subsequent SSc-ILD improvement.     

Body mass index in psoriatic patients with or without familial psoriasis

Psoriasis is a chronic inflammatory disease caused by both genetic and environmental factors. The occurrence of psoriasis in family members indicates a genetic predisposition, while obesity is also a major contributor to psoriasis. We examined whether patients with versus without familial psoriasis were obese at the onset of psoriasis. Clinical information, including age at onset, age at first visit and body mass index (BMI) at first visit, was extracted from the Fukuoka University Psoriasis Registry. To compare BMI, patients aged 10 years or older who visited the clinic within 3 years of onset were selected. Familial psoriasis was observed in 27 patients (15 male, 12 female) out of 428 individuals (264 male, 164 female) with psoriasis, accounting for 6.3% of cases. Age at onset was younger for both men and women with familial psoriasis (34 ± 17 and 40 ± 15 years, respectively) relative to those with non-familial psoriasis (48 ± 19 and 53 ± 19 years, respectively). We examined age- and sex-adjusted average values of BMI at initial presentation after onset of psoriasis, finding that patients with familial psoriasis had lower BMI (22.0 kg/m² [95% confidence interval, 21.8–22.4]) than those with non-familial psoriasis (23.2 [23.1–23.3], P < 0.001). Individuals with a family history of psoriasis should be considered to be at risk for developing the disease even if obesity is not present.     

Interleukin-17A suppresses granular layer formation in a 3-D human epidermis model through regulation of terminal differentiation genes

Immunotherapies targeting interleukin (IL)-17 greatly improve plaque psoriasis. Most previous studies on IL-17 focused on the T-helper (Th)17 immune response, but investigation of the effects of IL-17A on psoriatic epidermal structure are limited. Using an in vitro 3-D human epidermis model, we investigated the effects of IL-17A and IL-17C on morphological changes and gene expression. IL-17A directly suppressed the formation of the granular layer, whereas IL-17C did not. IL-17A significantly downregulated the gene expression of profilaggrin (FLG), which is a major component of keratohyalin granules in the granular layer. Global gene expression analysis of this 3-D epidermis model showed that both IL-17A and IL-17C upregulated S100A7A and type 1 interferon-related genes including MX1, IFI44L, XAF1 and IFIT1. However, only IL-17A directly downregulated keratinocyte differentiation-related and cornified envelope-related genes including FLG, LOR, C1ORF68, LCE1E, LCE1B, KRT10, CST6 and RPTN. In conclusion, IL-17A, a systemic inflammatory cytokine, affected keratinization in our 3-D epidermis model. In contrast, IL-17C, a locally produced cytokine, did not have strong effects on keratinization. Targeting IL-17A does not only reduce inflammation but it may also directly affect epidermal differentiation in psoriasis.