Characterization and tumorigenicity of ascites-derived cells in ovarian cancer

Objectives In the ascites fluid, detached cell aggregates (spheroids) from primary Ovarian Cancer (OvCa) regarded as floating “metastatic units”, attach to the peritoneum and invade the extracellular matrix. The aim of this project is to characterize cellular components and the tumorigenicity of ascites-derived cells in OvCa and further identify key molecular players involved in spheroids aggregation and attachment.

Material and methods CD24/EpCAM/CD45/CD90 FACs analysis were performed on purified cell fractions after filtering (15µm), as well as on cultured adherent cells (ADs) and non-adherent cells (NADs). E-Cadherin and cyclin A1 expression was analyzed by IHC (n = 4) and/or Western Blot (n = 14) on both ascites-derived cells (n = 12) and in part on matched tumor tissue (n = 36). Ascites-derived cells and cultured ADs were i.p. injected into scid mice (n = 29 and n = 7, respectively).

Results CD24/EpCAM and E-cadherin were highly expressed in almost all ascites-derived spheroids (>15µm cell fraction and NADs). CD90 was mainly expressed in ADs. Cyclin A1 was upregulated in ascites-derived spheroids (n = 8) compared to solid tumor (n = 8). Interestingly, ascites-derived spheroids (>15 µm) successfully developed peritoneal carcinomatosis in mice, while < 15µm cell fractions with low/no expression of CD24/EpCAM and ADs cannot.

Summary Our study identifies CD24/EpCAM, as well as E-cadherin and Cyclin A1 as markers for ascites-derived tumor cells with high tumorigenecity and metastatic potential.

Publication History

Article published online:
07 October 2020