DOCK7 and neoplasm: We then performed mouse xenograft experiments to examine the role of Dock7 and the unique actions of its DHR1 domain in survival in vivo during tumor formation by implanting MDA-MB-231 (vector control) cells, Dock7 knockdown cells, and Dock7 knockdown cells in which either DHR1L or DHR1L-C2M were semi-stably expressed (Figure 5I).