The mannose receptor LY75 (DEC205/CD205) modulates cellular phenotype and metastatic potential of ovarian cancer cells

Abstract

The molecular basis of epithelial ovarian cancer (EOC) dissemination is still poorly understood. Previously, we identified the mannose receptor LY75 gene as hypomethylated in high-grade (HG) serous EOC tumors, compared to normal ovarian tissues. LY75 represents endocytic receptor expressed on dendritic cells and so far, has been primarily studied for its role in antigen processing and presentation. Here we demonstrate that LY75 is overexpressed in advanced EOC and that LY75 suppression induces mesenchymal-to-epithelial transition (MET) in EOC cell lines with mesenchymal morphology (SKOV3 and TOV112), accompanied by reduction of their migratory and invasive capacity in vitro and enhanced tumor cell colonization and metastatic growth in vivo. LY75 knockdown in SKOV3 cells also resulted in predominant upregulation of functional pathways implicated in cell proliferation and metabolism, while pathways associated with cell signaling and adhesion, complement activation and immune response were mostly suppressed. Moreover, LY75 suppression had an opposite effect on EOC cell lines with epithelial phenotype (A2780s and OV2008), by directing epithelial-to-mesenchymal transition (EMT) associated with reduced capacity for in vivo EOC cell colonization, as similar/identical signaling pathways were reversely regulated, when compared to mesenchymal LY75 knockdown EOC cells.To our knowledge, this is the first report of a gene displaying such pleiotropic effects in sustaining the cellular phenotype of EOC cells and points to novel functions of this receptor in modulating EOC dissemination. Our data also support previous findings regarding the superior capacity of epithelial cancer cells in metastatic colonization of distant sites, compared to cancer cells with mesenchymal-like morphology.

Suppression of the grainyhead transcription factor 2 gene (GRHL2) inhibits the proliferation, migration, invasion and mediates cell cycle arrest of ovarian cancer cells

“…64 In our hands, the SKOV3 line displayed a typical spindle-like morphology and predominant expression of mesenchymal markers, although a strong expression of the epithelial marker EPCAM was also observed in this cell line. 65 Similarly, the A2780s cell line displayed an E/IE (round) phenotype accompanied with robust expression of epithelial markers; 65 however, a significant expression of the mesenchymal marker vimentin was also found in this cell line (data not shown). In contrast, the EOC cell lines used by Chung et al were bearing mostly the epithelial phenotype, which could explain the discrepancies between their and our data when analyzing the GRHL2 function in EOC cells.…”

“…The cell lines were passed in different culture media supplemented with 10% fetal bovine serum, as described previously. 65,67 Bisulfite sequencing PCR (BSP) analysis BSP analysis was performed, as described previously. 65,67 Briefly, genomic DNA extracted from EOC tumors and control ovarian tissues was isolated using the Qiagen DNeasy Blood and Tissue Kit.…”

“…65,67 Bisulfite sequencing PCR (BSP) analysis BSP analysis was performed, as described previously. 65,67 Briefly, genomic DNA extracted from EOC tumors and control ovarian tissues was isolated using the Qiagen DNeasy Blood and Tissue Kit. Bisulfite modification of genomic DNAs was done using the Methyl Detector kit (Active Motif, Carlsbad, CA).…”

“…TMA construction and IHC were performed as described previously. 65,67 Sections were incubated with anti-GRHL2 antibody (1:100 dilution) (GenTex) at 4 C overnight and GRHL2 protein expression was assessed by semi-quantitative scoring of the intensity of staining and recorded as absent (0), weak (1C), moderate (2C) or strong (3C). The relationship between GRHL2 expression in serous ovarian carcinomas and normal ovarian tissues was evaluated by the Mann-Whitney test.…”

CRISPR/Cas9‐mediated double knockout of SRPK1 and SRPK2 in a nasopharyngeal carcinoma cell line

“…First, we generated the single knockout of SRPK1 and SRPK2 NPC cells. Second, the flanking region was then excised by the Cre vector, rendering the transfected cells to become puromycin‐sensitive due to the removal of PAC gene . However, the Cre transfection rate in CNE1 was very low; we therefore reduced the amount of cells that were typically recommended from 20 000 to 1000 cells.…”