CS and urinary bladder cancer: Indeed, the rVAR2 proteins are specific for oncofetal CS, and binding to tumor cells can be competed with soluble CS, as shown in UM-UC3 bladder cancer cells (Fig. 1A) and tumor cell lines representing both mesenchymal and epithelial origins (Fig. EV1A) (Salanti et al, 2015; Seiler et al, 2017).