NU5455 (NU-5455) is a potent, highly selective, oral inhibitor of DNA-dependent protein kinase catalytic subunit (DNA-PKcs) activity with IC50 of 8.2 nM.NU5455 displays selectivity versus Vps34 (8.7-fold), PI3Kδ (33.7-fold), ATM/ATR (both >1200-fold), 228-fold selectivity margin for DNA-PKcs kinase activity versus that of PI3Kα.NU5455 inhibited radiation-induced activation of DNA-PK with an IC50 of 168 nM, but did not inhibit IGF-stimulated activation of AKT in MCF7 cells even at 10 uM.NU5455 inhibited the repair of DNA-DSBs induced by treatment with enzyme AfeI or ScaI restriction endonucleases within a 24-hour period in HEK293T cells, significantly increased the number of colocalized γH2AX and 53BP1 foci.NU5455 is a highly selective inhibitor of DNA-PKcs that is active in cells and that can perturb DNA-DSB repair by NHEJ.NU5455 preferentially augmented radiotherapy in subcutaneous Calu-6 and A549 lung tumor xenografts, increased both the efficacy and the toxicity of a parenterally administered topoisomerase inhibitor, NU5455 enhanced the activity of doxorubicin released locally in liver tumor xenografts without inducing any adverse effect.

Providing storage is as stated on the product vial and the vial is kept tightly sealed, the product can be stored for up to 24 months.
Wherever possible, you should prepare and use solutions on the same day. However, if you need to make up stock solutions in advance, we recommend that you store the solution as aliquots in tightly sealed vials at -20°C. Generally, these will be useable for up to one month. Before use, and prior to opening the vial we recommend that you allow your product to equilibrate to room temperature for at least 1 hour.