Doxorubicin resistant choriocarcinoma cell line derived spheroidal cells exhibit stem cell markers but reduced invasion

Cell cycle-specifc cancer chemotherapy is based on the ability of a drug to halt, minimise or destroy rapidly dividing cells. However, their efcacy is limited by the emergence of a self-renewing cell pool called “cancer stem cells” (CSC). Choriocarcinoma is a tumour of trophoblastic tissue. We, in this study, analysed whether spheroids generated from doxorubicintreated and non-treated choriocarcinoma cell lines exhibit markers of stem cells. Two choriocarcinoma cell lines, namely JEG-3 and BeWo, were used in this study. Spheroids were generated from doxorubicin-treated cells and the non-treated cells under non-adherent condition, followed by analysis of stem-cell markers’ expression, namely NANOG, OCT4 and SOX2. Immunofuorescence analysis suggested a general increase in the markers’ concentration in spheroids relative to the parental cells. RT-qPCR and immunoblots showed an increase in the stem-cell marker expression in spheroids generated from doxorubicin-treated when compared to non-treated cells. In spheroids, Sox2 was signifcantly upregulated in doxorubicintreated spheroids, whereas Nanog and Oct4 were generally downregulated when compared to non-treated spheroids. Both
2D and 3D invasion assays showed that the spheroids treated with doxorubicin exhibited reduced invasion. Our data suggest
that choriocarcinoma cell lines may have the potential to produce spheroidal cells, yet the drug-treatment afected the invasion potential of spheroids.