Interestingly, to date, only the RHO GEF VAV1 has a role in lymphomagenesis, either as a genetic driver in T-cell lymphoma (see specific paragraph in this review) or as a downstream molecule triggered by the oncogenic kinase anaplastic lymphoma kinase (ALK) in ALK-driven anaplastic large cell lymphoma (ALCL) [24,25,49,50]. The gene discussed is ALK; the disease is T-cell non-Hodgkin lymphoma.