BMX-IN-1 is a selective, irreversible inhibitor of bone marrow tyrosine kinase on chromosome X (BMX; IC50 = 8 nM) that targets Cys496 in the BMX ATP binding domain. It additionally targets the related Bruton’s tyrosine kinase (BTK) with an IC50 value of 10.4 nM, but is more than 47-656-fold less potent for inhibition of Blk, JAK3, EGFR, Itk, or Tec activity. BMX-IN-1 was shown to inhibit the proliferation of Tel-BMX-transformed Ba/F3 prostate cancer cells with a GI50 value of 25 nM. Antiproliferative activity was also observed in RV-1, DU-145, PC-3, and VCAP prostate cancer cell lines (GI50s = 2.54, 4.38, 5.37, and 2.46 μM, respectively).
