PAK1 reduction inhibits AML progression in vivo. (A) Gross liver and spleen images 46 days after transplantation of 3 × 105 sh control, shPAK1#1, or shPAK1#2 THP-1 cells (4 animals per group per experiment; n = 2). (B) Hematoxylin and eosin (H&E) staining of femur, liver, and spleen sections of transplanted animals. (C) Chimerism of human THP-1 cells in the liver quantified by flow cytometry for cells expressing human CD45. Data represent the mean ± standard deviation. (D) CD11b expression levels on the surface of human CD45 expressing THP-1 cells isolated from the livers of animals transplanted with THP-1 cells expressing the control shRNA lentivirus or 1 of 2 PAK1 targeting sequences. (E) Cytospin preparations and Wright-Giemsa staining of THP-1 cells FACS sorted from the livers of transplanted animals. The few remaining cells that could be isolated from animals receiving PAK1 knockdown cells exhibit signs of myelomonocytic differentiation. *P < .05 for all experiments.
