Fecal microbiota transplantation (FMT) has been recognized as a promising treatment for dysbiosis-related diseases. Since 2014, FMT has been utilized to treat ulcerative colitis (UC) in our clinical studies and has shown efficacy and safety. As donor screening (DS) is the primary step to ensure the safety of FMT, we report our experience with DS and present the screening results to improve the prospective DS criteria and provide references for future studies. The donor candidates were screened according to the DS criteria. The first DS criteria were proposed in June 2014 and revised substantially in May 2018. We further sorted the screening results and costs of laboratory tests. From June 2014 to April 2018, the DS eligibility rate was 50%. The total laboratory testing cost for each candidate was JPY 17,580/USD 160.21. From May 2018 to September 2021, the DS eligibility rate was 25.6%. The total laboratory testing cost for each candidate was JPY 40,740/USD 371.36. The reduction in donor eligibility rates due to more stringent criteria should be considered for cost and safety. Studies must consider the latest updates and make timely modifications in the DS criteria to ensure patient safety.

Background and Aims: Clinical applications of fecal microbiota transplantation (FMT) for treating ulcerative colitis (UC) have shown promising results. However, whether the beneficial effects of FMT are due to the transfer and colonization of donor-derived species in patients remains unclear. Here, we investigated the factors affecting the efficacy of the administration of triple antibiotics (A-FMT) and the criteria for appropriate donor and patient–donor matching. Methods: Ninety-seven patients with active UC who were enrolled between March 2014 and October 2019 underwent FMT. The clinical features were assessed based on a reduction in Lichtiger’s clinical activity index 4 weeks after A-FMT, with long-term responders (LTR) defined as those with no increase or intensification within 12 months after A-FMT. Microbiome analysis was performed on 147 fecal samples (pre-A-FMT, post-A-FMT, and donor) from 49 patient–donor combinations that were assigned using the one-patient-to-one-donor strategy. Results: Of the 97 patients, 61 achieved a clinical response, and of those, 35 were classified as having clinical remission. The efficacy of A-FMT was affected by UC severity and previous administration of steroids (P = .027), immunosuppressants (P = .049), and biologics (P = .029). Effective donors were rich in taxa such as Bacteroidota, which are lost in UC, and the abundances of “patient-origin” and “new-amplicon sequence variant” taxa were significantly lower in Responders compared to Nonresponders (Remission; P = .03, LTR; P = .05). “Donor-derived” amplicon sequence variant sequences, Oscillospiraceae UCG−002 and Alistipes, were significantly enriched in Responders (P < .05). Our results showed that the taxonomic composition of patients and the similarity of Bacteroides and butyric-acid-producing bacteria in the patient–donor microbiota significantly influenced A-FMT efficacy (P < .05). Conclusions: This study provides important insights for developing patient-tailored FMT-based therapies for UC.

Background/Aim: The oncoproteins murine double minute (MDM) 2 and MDM4 inactivate tumor-suppressor protein p53. Their mutual relationship with the prognosis of gastric cancer (GC) remains unknown. Patients and Methods: Expression of MDM2, MDM4, and p53 in tumors of 241 patients with GC were evaluated immunohistochemically. Effects of overexpression of MDM4 on tumor-growth properties and sensitivity to cytotoxic drugs were investigated using NUGC4 human GC cell line. Results: High expression of p53 was associated with poor overall survival in the whole population. Among 173 patients with low expression of p53 (implying nonmutation), high expression of MDM4 was an independent factor of poor prognosis in both stage I-III and IV, but of MDM2 was not. MDM4-transduced NUGC4 cells formed twice as many colonies and had a higher 50% inhibitory concentration for 5-fluorouracil and oxaliplatin than did the control cells. Conclusion: MDM4 expression is a factor conferring poor prognosis in patients with GC with low expression of p53 and may confer drug resistance.

The gut microbiota plays an integral role in maintaining health and regulating various host functions, including immune responses. Fecal microbiota transplantation (FMT) has emerged as a promising therapeutic approach to restore gut microbial balance. Although widely recognized for its efficacy in treating ulcerative colitis (UC), FMT is now being investigated as an adjuvant therapy to enhance the efficacy of immune checkpoint inhibitors (ICIs) in cancer treatment. This review summarizes the clinical applications of FMT in UC treatment and its potential role in cancer immunotherapy. FMT exhibits varying degrees of efficacy in the treatment of UC, with differences in outcomes attributed to variations in administration methods and donor selection. In cancer therapy, FMT has demonstrated the potential to improve ICI responses, particularly in patients with melanoma. However, its effects on other cancers remain unclear. Although FMT holds promise for UC and cancer immunotherapy, challenges such as inconsistent clinical outcomes and methodological variations persist. Standardized protocols and mechanistic studies are crucial to optimize FMT-based therapeutic strategies, and further research is required to establish its efficacy under diverse clinical conditions.