IC50: 88 nM
PS-1145 is an IkappaB kinase (IKK) inhibitor.
The IκB kinase is an enzyme complex involved in propagating the cellular response to inflammation. This enzyme complex is reported to be part of the upstream NF-κB signal transduction cascade.
In vitro: Previous study found that PS-1145 could block TNFalpha-induced NF-kappaB activation in a dose- and time-dependent manner in MM cells, which up-regulated IkappaBalpha protein, enhanced blockade of NF-kappaB activation. In addition, PS-1145 blocked the protective effect of IL-6 against Dex-induced apotosis and TNFalpha-induced ICAM-1 expression was also inhibited by PS-1145. Moreover, PS-1145 inhibited both IL-6 secretion from BMSCs triggered by MM cell adhesion and proliferation of MM cells adherent to BMSCs. However, PS-1145 could only partially inhibit MM cell proliferation. Importantly, it was found that TNFalpha induced MM cell toxicity in the presence of PS-1145 [1]
In vivo: Animal study showed that the intravenous application of PS-1145 could promote direct apoptosis in DMBA-induced skin tumor in male Wistar rats via blocking NF-κB and VEGF activities [2].
Clinical trial: Up to now, PS-1145 is still in the preclinical development stage.
References:
[1] Hideshima T,Chauhan D,Richardson P,Mitsiades C,Mitsiades N,Hayashi T,Munshi N,Dang L,Castro A,Palombella V,Adams J,Anderson KC. NF-kappa B as a therapeutic target in multiple myeloma. J Biol Chem.2002 May 10;277(19):16639-47.
[2] Rajmani RS,Gandham RK,Gupta SK,et al. Administration of IκB-kinase inhibitor PS1145 enhances apoptosis in DMBA-induced tumor in male Wistar rats. Cell Biol Int.2015 Nov;39(11):1317-28.