Takayuki Iwamoto
   Department   Kawasaki Medical School  Kawasaki Medical School, Department of Breast and Thyroid Surgery,
   Position   Assistant Professor
Article types 原著
Language English
Peer review Peer reviewed
Title Immunological profiles of the breast cancer microenvironment represented by tumor-infiltrating lymphocytes and PD-L1 expression.
Journal Formal name：Scientific reports
Abbreviation：Sci Rep
ISSN code：20452322/20452322
Domestic / ForeginForegin
Volume, Issue, Page 12(1),pp.8098
Author and coauthor Toru Hanamura, Shigehisa Kitano, Hiroshi Kagamu, Makiko Yamashita, Mayako Terao, Banri Tsuda, Takuho Okamura, Nobue Kumaki, Katsuto Hozumi, Naoki Harada, Takayuki Iwamoto, Chikako Honda, Sasagu Kurozumi, Naoki Niikura
Publication date 2022/05
Summary Tumor-infiltrating lymphocytes (TILs) and programmed cell death 1 ligand 1 (PD-L1) are established prognostic and predictive biomarkers for certain breast cancer subsets. However, their association with the immune response complexity is not fully understood. Therefore, we analyzed the association between the immune cell fractions in breast cancer tissues and histologically assessed TIL (hTIL) and PD-L1 (hPD-L1). Forty-five tumor and eighteen blood samples were collected from patients with breast cancer. Total leukocyte counts, frequency of 11 immune cell populations, and PD-L1 expression in each cell fraction were evaluated by flow cytometry. TILs and PD-L1 were assessed by hematoxylin and eosin staining and immunohistochemistry, respectively. A higher hTIL score showed association with increased leukocyte infiltration, higher CD4+ and CD8+ T cell proportions, and lower natural killer and natural killer T cell proportions. PD-L1 was highly expressed in nonclassical monocytes, monocyte/macrophages, myeloid-derived suppressor cells, myeloid dendritic cells, dendritic cells, and other lineages in tumors. hPD-L1 positivity reflected PD-L1 expression accurately in these fractions, as well as increased leukocyte infiltration in tumors. These results indicate that hTILs reflect differences in the immune responses in the tumor microenvironment, and certain immune cell fractions are favorably expressed in the PD-L1 pathway in breast cancer microenvironments.
DOI 10.1038/s41598-022-11578-x
PMID 35577913