Cd4-RhoA G17V promotes T-cell transformation in concert with Tet2 loss. (A) Overall survival from birth for Tet2^fl/fl; Vav-Cre⁺; OT-II (red, n = 10), tgRhoA; Tet2^fl/fl; Vav-Cre⁺; OT-II (blue, n = 10), or Tet2^fl/fl; OT-II (green, n = 4) mice. Mice were immunized monthly with NP40-Ovalbumin, using alum as an adjuvant for up to 7 injections. One mouse from Tet2^fl/fl; Vav-Cre⁺; OT-II and 1 mouse from tgRhoA; Tet2^fl/fl; Vav-Cre⁺; OT-II cohorts were found dead and could not be analyzed. P < .0001 by Mantel-Cox test. (B) Survival of Tet2^fl/fl; Vav-Cre⁺; OT-II (red, n = 3) or tgRhoA; Tet2^fl/fl; Vav-Cre⁺; OT-II (blue, n = 4) mice that were confirmed to have developed T-cell tumors. P = .0177 by Mantel-Cox test. (C) Immunohistochemistry of tgRhoA; Tet2^fl/fl; Vav-Cre⁺; OT-II lymphoma from a mouse that required euthanasia 231 days after birth showing T-cell infiltrate of lymph node and liver with markers as noted. Scale bars, 100 μM. Images taken at ×1000 except for B220 at ×200. (D) Immunohistochemical analysis of the spleen from a mouse transplanted with T-cell tumor 1 from tgRhoA; Tet2^fl/fl; Vav-Cre⁺; OT-II donor. Scale bars, 100 μM. Images taken at ×400. (E) Flow cytometric analysis of CD4⁺ tumor cells from primary tgRhoA; Tet2^fl/fl; Vav-Cre⁺; OT-II mouse and from secondary recipient. (F) GSEA of Hallmark mTORc1 gene set compared with Tet2^fl/fl; Vav-Cre⁺; OT-II T_FH cells (FDR q = 0.001125).