ROR1 and B-cell acute lymphoblastic leukemia: Moreover, other Wnt ligands have been shown to interact with either ROR1 or ROR2 in various cellular contexts, such as Wnt16–ROR1 interaction in TCF3-PBX1 B-cell acute lymphoblastic leukemia [13] and Wnt9a–ROR2 interaction during skeletal development [14].