We therefore investigated the effects of Dock7 on the ability of breast cancer cells to undergo anchorage-independent growth, a hallmark of transformation and a cellular stressor as cells are forced to grow in the absence of a substratum.55 Upon knocking down Dock7, we observed a striking decrease in the ability of triple-negative MDA-MB-231 breast cancer cells, as well as receptor-positive SK-BR-3 and MCF7 breast cancer cells, to form colonies in soft agar (Figure 2D). Here, DOCK7 is linked to breast carcinoma.