USP1 inhibition suppresses T-ALL cell proliferation in vitro and in vivo. (A-B) Jurkat and MOLT4 cells were infected with control shRNA or USP1 shRNAs, and cell proliferation was monitored by CCK-8 array. USP1 expression in cells was measured by immunoblotting (left). (C) Jurkat cells stably expression control or USP1-shRNA were injected into NPG nude mice. The body weights of mice are shown (mean ± standard deviation [SD] of 9 mice). Two-sided t test. (D-E) After 25 days, the mice were killed and their T-ALL progression was analyzed. Representative spleen images are shown in panel D. The spleen weights are shown (n = 9 in control and USP1 shRNA cohort). Two-sided Mann-Whitney tests. (F) Representative spleen H&E and immunohistochemistry images are presented. (G) Representative bone H&E and immunohistochemistry images are presented. Scale bars, 50 μM (F-G). (H) Wright staining of BM (top) and peripheral blood (bottom) cytospin samples from the control mice and USP1-depleted mice. (I) Mouse survival is shown (n = 6 in the control and USP1-shRNA cohort).