Environmental physical factors produce mitotic aberration and multicellularity in the ovarian cancer cell line SKOV3.

The spread of ovarian cancer (OC) to the coelomic cavity triggers the secretion and accumulation of ascitic fluid (AF). Although its biochemical composition has been well studied, less is known about the implications of physical factors such as the pH and the mechanical properties of the AF for the malignancy of tumor cells. In this work, we investigated the effect of pH and the mechanical properties of AF on cell proliferation and mitotic morphology. We employed biopsies from patients with OC and the SKOV3 cell line as an in vitro model of OC with HeLa cells as controls. Sections of each tumor were stained with HE, analyzed, and related to clinical data. AF from patients with OC exhibited an alkaline pH (ranging from 7.3 to 7.8). Compared to control conditions, the 3 AFs significantly enhanced the proliferation of SKOV3 and HeLa cells. These effects were more pronounced at a more alkaline pH. In addition, we found that AFs have different densities that correlated with a significant increase in multinucleated tumor cells and severe morphological defects in cells undergoing mitosis. In agreement with these data, we found that higher concentrations of soft agar provoked significantly higher numbers of multinucleated and morphologically abnormal SKOV3 cells with no effect on HeLa cells. We conclude that an alkaline pH and greater rigidity could enhance the metastatic potential of OC cells. We propose that these two physical factors could be parameters of clinical importance as predictors of malignancy.