Surprisingly, DKK1 functions through the DKK1/CKAP4/PI3K pathway to augment the expression of plasmalemma vesicle-associated protein in cholangiocarcinoma cells, which is positively linked to angiogenesis in various tumors, hence also making this pathway a prospective anti-angiogenic target (Wang et al., 2021). This evidence concerns the gene CKAP4 and cholangiocarcinoma.