廣岡 芳樹

Background and Aims: Crohn’s disease (CD) is a chronic inflammatory bowel disease characterized by gastrointestinal inflammation, with gut microbiota dysbiosis playing a key role in its onset and progression. This study aimed to evaluate whether 1-kestose supplementation modulates gut microbiota composition and mucin degradation–related biomarkers in patients with clinically inactive to mild CD, and to explore plausible ecological mechanisms in vitro. Study Design: Single-arm pilot intervention study with exploratory laboratory experiments. Place and Duration of Study: Samples were collected at Tokai University Hospital (Japan), and microbiome/qPCR analyses and in vitro assays were performed at Fujita Health University (Japan). The supplementation period was four months. Methodology: Nineteen patients with clinically inactive to mild CD (CDAI ≤ 220) received 1-kestose (3 g) twice daily for 4 months. Fecal microbiota composition was assessed by 16S rRNA gene sequencing, and qPCR quantified nanA homologs (nan levels) as a functional marker related to mucin-degrading potential. Clinical biomarkers (CDAI, fecal calprotectin, CRP, albumin) were monitored. To investigate potential mechanisms, in vitro cultures of Ruminococcus gnavus and Bifidobacterium longum were performed under sugar-supplemented conditions, including 1-kestose, and growth responses were evaluated; short-chain fatty acids (SCFAs) were descriptively assessed in pooled culture supernatants. Results: Clinical biomarkers remained stable throughout supplementation. 1-kestose intake was associated with an increased relative abundance of Bifidobacterium and a decreased abundance of Blautia, along with reduced fecal nan levels. In vitro, B. longum showed enhanced early growth with 1-kestose compared with other sugars, whereas R. gnavus exhibited impaired growth under acidic conditions. Exploratory SCFA measurements suggested higher acetate in sugar-supplemented B. longum cultures. Conclusion: In this single-arm pilot cohort of patients with clinically inactive to mild CD, 1-kestose supplementation was associated with shifts toward potentially beneficial taxa and a reduction in nan levels, a functional marker linked to mucin-degrading potential. These findings, supported by exploratory in vitro observations, suggest that 1-kestose may modulate gut ecological conditions; however, clinical efficacy and causality require confirmation in randomized, placebo-controlled trials with detailed dietary and medication monitoring.

BACKGROUND/AIM: Atezolizumab plus bevacizumab (Ate+Bev) is widely used as first-line therapy for unresectable hepatocellular carcinoma (HCC). However, a subset of patients experience early disease progression, often detected at the first radiologic assessment around 6 weeks. Evidence guiding second-line therapy in this subgroup is limited, and the clinical value of lenvatinib after early progressive disease (PD) remains unclear. PATIENTS AND METHODS: We retrospectively analyzed 36 patients with unresectable HCC who received lenvatinib after failure of first-line Ate+Bev. Patients were stratified by early PD, defined as radiologic progression at the scheduled 6-week assessment after starting Ate+Bev. Outcomes included antitumor response, progression-free survival (PFS), and overall survival (OS). RESULTS: Objective response rate (ORR) and disease control rate (DCR) assessed by RECIST 1.1 were comparable between patients with and without early PD (ORR: 28.6% vs. 13.8%; DCR: 85.7% vs. 86.2%; p=0.342). Median PFS was also similar between groups [5.2 months (95% confidence interval=1.9-NA) vs. 6.1 months (3.7-7.5); p=0.307]. In multivariate analyses adjusting for Child-Pugh class, Barcelona Clinic Liver Cancer (BCLC) stage, and reduced starting dose, early PD was not significantly associated with either PFS or OS, whereas Child-Pugh class A was independently associated with improved OS. Correlation between first- and second-line PFS was weak and non-significant (r=0.077, p=0.682). CONCLUSION: Lenvatinib demonstrated comparable antitumor activity and survival outcomes even in patients with early PD on first-line Ate+Bev, indicating that early radiologic progression does not necessarily signify refractoriness to subsequent systemic therapy. These findings support lenvatinib as a viable second-line option regardless of early Ate+Bev response, particularly in patients with preserved liver function. Larger prospective studies are needed to confirm these observations.

Aims: To characterize fecal gut microbiota features associated with a history of aggression in dogs and to explore whether supplementation with the prebiotic fructooligosaccharide 1-kestose is associated with alterations in gut microbiota composition and owner-reported aggression-related behaviors. Study Design: An exploratory, non-randomized field study comparing aggressive and non-aggressive client-owned dogs, followed by a single-arm pre–post supplementation study in aggressive dogs with owner-reported behavioral outcomes. Place and Duration of Study: The study was conducted in Japan between 2021 and 2023, with a 60-day 1-kestose supplementation period for the intervention group. Methodology: Fecal samples from aggressive toy poodles (Agg; n = 10) and non-aggressive controls (N-Agg; n = 6) were analyzed using 16S rRNA gene sequencing. Dogs in the Agg group received 1-kestose (400 mg/day) for 60 days. Behavioral outcomes were assessed before and after supplementation using the shortened, owner-reported Canine Behavioral Assessment and Research Questionnaire (C-BARQ). Genome analysis of Blautia caecimuris was conducted to identify glycoside hydrolase family 32 (GH32) enzymes, and a recombinant GH32 enzyme was functionally characterized for fructooligosaccharide hydrolysis. Results: At baseline, Agg dogs differed in gut microbial β-diversity from N-Agg dogs and showed higher relative abundances of Mediterraneibacter gnavus, the Segatella copri group, and the Phocaeicola vulgatus group. Following 1-kestose supplementation, M. gnavus was lower, the B. caecimuris group was higher, and the β-diversity difference between groups diminished. In parallel, owner-reported aggression-related C-BARQ items—particularly responses to unfamiliar dogs and strangers near the home—were lower after supplementation. The characterized GH32 enzyme from B. caecimuris hydrolyzed 1-kestose and nystose. Conclusion: These findings indicate that 1-kestose supplementation is associated with concurrent alterations in the canine gut microbiota and owner-reported aggression-related behavioral scores. While causality cannot be established, the results support further investigation of microbiota–behavior associations using larger, well-controlled study designs incorporating objective physiological and microbial measurements.

BACKGROUND: Atezolizumab plus bevacizumab (AB) is a standard first-line therapy for unresectable hepatocellular carcinoma (HCC). However, data on the efficacy and safety of AB rechallenge (re-AB) after discontinuation are limited. METHODS: We conducted a retrospective analysis of 13 patients with unresectable HCC who received initial AB treatment and re-AB at the University of Yamanashi and Fujita Health University. Rechallenge was defined as reinitiating AB after prior discontinuation followed by one or more other systemic therapies. Tumor responses were assessed using RECIST v1.1 and modified RECIST (mRECIST), and adverse events (AEs) were evaluated according to CTCAE v5.0. RESULTS: During initial AB, the objective response rate (ORR), disease control rate (DCR), and median progression-free survival (mPFS) were 15%, 69%, and 3.7 months, respectively. AB was discontinued due to disease progression or immune-related AEs. Re-AB was administered after a median of two intervening regimens. In the re-AB phase, ORR, DCR, and mPFS were 15%, 54%, and 4.7 months, respectively. Despite prior progression, two patients achieved partial response and five had stable disease. No worsening of previously observed AEs occurred during re-AB. CONCLUSIONS: AB rechallenge may be a safe and potentially effective treatment option for selected patients with unresectable HCC, even after discontinuation due to disease progression or adverse events.