The present invention relates to a clonally pure population of serosal cancer stem cells (CSCs) as well as methods of producing and culturing the CSCs and uses thereof. The CSCs form catenae (free floating chains of cells) which have a glycocalyx coat of hyaluronan and proteoglycans. This discovery has lead to the development of methods of treating serosal and ovarian cancers by targeting removal or inhibition of glycocalyx formation, including combination therapies using chemotherapeutics in conjunction with glycocalyx inhibitors. The invention also provides drug screening assays for identifying compounds effective against these CSCs as well as other serosal cancer cells. Methods to use catena gene signatures, protein and surface antigens are provided for monitoring patient samples for the presence of serosal cancer stem cells.
