BI-D1870 (501437-28-1) is an inhibitor of p90 ribosomal S6 kinase (RSK; IC50’s = RSK1, 31 nM; RSK2, 24 nM; RSK3, 18 nM; RSK4, 15 nM) with selectivity over other AGC kinases.1 It protected mice from experimental autoimmune encephalomyelitis suggesting a new strategy to treat multiple sclerosis.2 BI-D1870 has also been found to alter mTORC1 signaling in an RSK-independent manner.3 BI-D1870 induced apoptosis in oral squamous cell carcinoma cells4, suppressed growth and induced apoptosis in pediatric medulloblastoma cell lines as well as sensitizing these lines to Sonic hedgehog agents5, and blocked cell proliferation and protein synthesis in dual BRAF and MEK inhibitor-resistant melanoma6.
1) Gopal et al. (2007), BI-D1870 is a specific inhibitor of the p90 RSK (ribosomal S6 kinase) isoforms in vitro and in vivo; Biochem. J. 401 (Pt 1) 29
2) Takda et al. (2016), The ribosomal S6 kinase inhibitor BI-D1870 ameliorated experimental autoimmune encephalomyelitis in mice; Immunobiology 221 188
3) Roffe et al. (2015), Two widely used RSK inhibitors, BI-D1870 and SL0101, alter mTORC1 signaling in a RSK-independent manner; Cell Signal. 27 1630
4) Chiu et al. (2014), Antitumor effects of BI-D1870 on human oral squamous cell carcinoma; Cancer Chemother. Pharmacol. 73 237
5) Pambid et al. (2014), Overcoming resistance to Sonic hedgehog inhibition by targeting p90 ribosomal S6 kinase in pediatric medulloblastoma; Pediatr. Blood Cancer 61 107
6) Theodosakis et al. (2017), p90RSK Blockade Inhibits Dual BRAF and MEK Inhibitor-Resistant Melanoma by Targeting Protein Synthesis; J. Invest. Dermatol. 137 2187