RRBP1 and neoplasm: Furthermore, in a UTUC patient-derived organoid model, high expression levels of RRBP1 have been associated with chemoresistance to cisplatin, gemcitabine and epirubicin (8); therefore, it synergistically promotes tumor cell survival by modulating ERS and yes-associated protein 1 (YAP1) signaling (Fig. 4) (8).