Shinya Sato

Crucial immunological roles of the invasion front in innate and adaptive immunity in cervical cancer

The immunostimulatory actions of innate and adaptive immune responses play a crucial role in the cancer-immunity cycle. Although cervical cancer (CC) exhibits a high recurrence rate, the relation with lymphocytes in the tumor tissue have not been analyzed. We analyzed NKT, NK, and T cells, not only in peripheral blood (PB), but also tumor tissue through histological analysis from 23 patients with CC collected before treatment. A correlation of them between PB and the tumor tissue were assessed. We detected functional NKT and NKG2D LAG-3

Tissue factor pathway inhibitor-2 inhibits integrin β1 activation and focal adhesion formation and suppresses peritoneal ovarian cancer dissemination in mice

Tissue factor pathway inhibitor-2 (TFPI2) is a Kunitz-type serine protease inhibitor and an ovarian clear cell carcinoma (CCC) biomarker. TFPI2 is expressed in several cancers and exerts tumor-suppressive effects; however, the role of TFPI2 in the CCC cell phenotype remains unclear. Therefore, in this study, we investigated the function of TFPI2 by establishing a gene knockout (KO) in ES-2 CCC cells and observed the change in phenotypes in vitro and in vivo. TFPI2 KO inhibited ES-2 cell proliferation, increased extracellular matrix protein adhesion, enhanced focal adhesion formation and activated integrin β1 cell surface clustering in vitro, and markedly increased ES-2 tumor growth and dissemination in the peritoneal cavity of a mouse xenograft model. These findings suggest a novel function of TFPI2 expression in suppressing the formation of focal adhesions in CCC cells, potentially by activating integrin β1. This function plays a role in the peritoneal growth characteristics of CCC cells.

Characterization of immortalized ovarian epithelial cells with BRCA1/2 mutation

We aimed to elucidate the mechanism underlying carcinogenesis by comparing normal and BRCA1/2-mutated ovarian epithelial cells established via Sendai virus-based immortalization. Ovarian epithelial cells (normal epithelium: Ovn; with germline BRCA1 mutation: OvBRCA1; with germline BRCA2 mutation: OvBRCA2) were infected with Sendai virus vectors carrying three immortalization genes (Bmi-1, hTERT, and SV40T). The immunoreactivity to anti-epithelial cellular adhesion molecule (EpCAM) antibodies in each cell line and cells after 25 passages was confirmed using flow cytometry. Chromosomes were identified and karyotyped to detect numerical and structural abnormalities. Total RNA extracted from the cells was subjected to human transcriptome sequencing. Highly expressed genes in each cell line were confirmed using real-time polymerase chain reaction. Immortalization techniques allowed 25 or more passages of Ovn, OvBRCA1, and OvBRCA2 cells. No anti-EpCAM antibody reactions were observed in primary cultures or after long-term passages of each cell line. Structural abnormalities in the chromosomes were observed in each cell line; however, the abnormal chromosomes were successfully separated from the normal structures via cloning. Only normal cells from each cell line were cloned. MMP1, CCL2, and PAPPA were more predominantly expressed in OvBRCA1 and OvBRCA2 cells than in Ovn cells. Immortalized ovarian cells derived from patients with germline BRCA1 or BRCA2 mutations showed substantially higher MMP1 expression than normal ovarian cells. However, the findings need to be validated in the future.