Objective: The antitumor effects of anti-PD-1 antibody against mismatch repair deficiency (MMR-D)-associated cancers have been reported. MMR-D is found in approximately 20%–30% of endometrial carcinomas (ECs) and frequently occurs due to MLH1 promoter hypermethylation (MLH1-PHM). ECs with MLH1-PHM are classified according to the molecular screening of Lynch syndrome (LS), but few detailed reports are available. The purpose of this study was to clarify the clinical features of EC with MLH1-PHM. Methods: Immunohistochemistry of MMR proteins (MLH1, MSH2, MSH6, and PMS2) was performed on specimens from 527 ECs treated at our university hospital from 2003 to 2018. MLH1 methylation analysis was added to cases with MLH1/PMS2 loss. ECs were classified as follows: cases that retained MMR proteins as “MMR-proficient;” cases with MLH1/PMS2 loss and MLH1-PHM as “met-EC;” and cases with other MMR protein loss and MLH1/PMS2 loss without MLH1-PHM as “suspected-LS.” The clinical features, including long-term prognosis, of each group, were analyzed. Results: Accordingly, 419 (79.5%), 65 (12.3%), and 43 (8.2%) cases were categorized as “MMR-proficient,” “suspected-LS,” and “met-EC,” respectively. Significantly, “met-EC” had a lower proportion of grade 1 tumors (37.5%) and a higher proportion of stage III/IV tumors (37.2%) than the other groups. The overall and progression-free survival of “met-EC” were significantly worse than those of “suspected-LS” in all cases. Conclusion In ECs with MMR-D, “met-ECs” were a subgroup with a poorer prognosis than “suspected-LS.” “Met-ECs” would be the main target for anti-PD-1 antibody treatment, and its clinical susceptibility should be verified individually.

This study aimed to evaluate the effects of ingesting yogurt fermented with Lactobacillus delbrueckii subsp. bulgaricus (OLL1073R-1) on the immune function of healthy university men track and field athletes. Study design Randomized, double-blind, placebo-controlled, parallel-group study. A total of 37 track and field athletes aged ≥18 years were randomly assigned into two groups. For 2 weeks, two bottles of yogurt fermented with OLL1073R-1 and Streptococcus thermophilus OLS3059 or placebo sour milk were ingested daily to the participants. During the intake period, a 1-week training camp was held and participants were subjected to strenuous exercise. Natural killer (NK) cell activity, which is the primary endpoint, was significantly lower in the placebo group after ingestion than that at baseline; however, it remained unchanged during the pre-exercise level of the yogurt group. The two-way repeated measures analysis of variance showed an interaction effect in the NK cell activity change (P=0.018) and a significant difference between the groups after the 2-week ingestion (P=0.015). Among the secondary endpoints, cytokines and chemokines levels involved in activating innate immunity maintained or enhanced only in the yogurt group. ALT, LDH, and CK significantly elevated only in the placebo group. Furthermore, amino acid levels were significantly lower in the placebo group after ingestion than that at baseline; however, it remained unchanged during the pre-exercise level in the yogurt group. Consuming yogurt fermented with OLL1073R-1 prevents the decline in immune function associated with strenuous exercise. Additionally, the yogurt may contribute to stable physical condition.