It has been reported that 4T1 tumor growth is associated with increased splenomegaly or splenomegaly-associated inflammation, and various tumor-derived cytokines, such as G-CSF, GM-CSF, and IFN-γ, may be responsible for the splenomegaly in mice injected with 4T1 cells [44]. The gene discussed is CSF2; the disease is Splenomegaly.