VAV1 and cancer: In addition, numerous studies have reported the unexpected expression of Vav1, normally found only in the hematopoietic system, in a variety of human cancers, such as neuroblastoma (Hornstein et al, 2003), lung (Lazer et al, 2009), breast (Lane et al, 2008; Sebban et al, 2013; Du et al, 2014; Grassilli et al, 2014), ovarian (Wakahashi et al, 2013), prostate (Kniazev Iu et al, 2003), esophageal (Zhu et al, 2017), and brain tumors (Lindsey et al, 2014).