EIF4B and cholangiocarcinoma: Subsequent co-incubation assay showed that the transfer of RBE-derived exosomal miR-30a-5p to endothelium was apparently decreased after EIF4B silencing in CCA cells, regardless of hypoxia or normxia (Fig. 6N), suggesting EIF4B play a critical role in mediating miR-30a-5p packing into exosomes.