WNT5A and breast cancer: Based on these findings, mastoparan was used to directly activate heterotrimeric Gi/o proteins in WNT5A-negative breast cancer cells, resulting in reconstitution of collagen to induce phosphorylation of DDR1 and an increased adhesiveness of these breast cancer cells, thereby proposing the therapeutic notion to use mastoparan to reinstall WNT5A signaling in WNT5A-negative breast cancer [28].