真里谷 奨

Recently, the Tohoku Medical Megabank Organization released whole-genome allele frequencies of single-nucleotide variants and indels from approximately 60,000 individuals from the general Japanese population in the Tohoku region (60KJPN). Here we analyzed the 60KJPN dataset for BRCA1/BRCA2 variants and compared them with the previous version, 54KJPN, to ascertain the frequency of hereditary breast and ovarian cancers in the general Japanese population. We hope that these results will contribute to strategies for cancer prevention.

Placenta accreta spectrum (PAS) is a serious disease leading to complications and maternal death. The objective of the study was to characterize the placental villi and blood vessels of PAS villi histopathologically. We investigated 10 cases of PAS (five cases of placenta increta, two cases of placenta accreta, and three cases of placenta percreta) histologically. Immunohistochemical staining using anti-CD68 or anti-CD163 antibodies was performed to detect and count Hofbauer cells. Immunohistochemical staining with an anti-CD34 antibody was used to detect vascular endothelial cells, and the number and area of vessels were analyzed. The numbers of CD68-positive or CD163-positive Hofbauer cells were larger in PAS cases compared with control cases. The vascular area in villi was smaller in PAS cases compared with control cases. The number of blood vessels in villi was slightly higher in PAS cases than in control cases. The numbers of Hofbauer cells and vessels in villi were larger in PAS cases compared with control cases, whereas the area of vessels in villi was smaller in PAS cases compared with control cases. Although their biological meaning is elusive, these findings provide novel insights into the pathogenesis of PAS, particularly regarding the role of Hofbauer cells in immune-suppressive role and angiogenesis and the alterations in vascular structure and hemodynamics in the chorionic villi.

Tumor-reactive CD4+ T cells often accumulate in the tumor microenvironment (TME) in human cancer, but their functions and roles in antitumor responses remain elusive. Here, we investigated the immunopeptidome of HLA class II-positive (HLA-II+) endometrial cancer with an inflamed TME using a proteogenomic approach. We identified HLA-II neoantigens, one of which induced polyclonal CD4+ tumor-infiltrating lymphocyte responses. We then experimentally demonstrated that neoantigen-specific CD4+ tumor-infiltrating lymphocytes lyse target cells in an HLA-II-dependent manner. Single-cell transcriptomic analysis of the TME coupled with T-cell receptor sequencing revealed the presence of CD4+ T-cell clusters characterized by CXCL13 expression. The CXCL13+ clusters contained two subclusters with distinct cytotoxic gene expression patterns. The identified neoantigen-specific CD4+ T cells were found exclusively in one of the CXCL13+ subclusters characterized by granzyme B and CCL5 expression. These results demonstrate the involvement of tumor-reactive CD4+ T cells with cytotoxic function in immune surveillance of endometrial cancer and reveal their transcriptomic signature.