RSK2/TOP2-IN-1 is a dual inhibitor targeting RSK2 and TOP2 enzymes. It specifically targets critical enzymes related to tumor progression, including ribosomal S6 kinase (RSK2) and topoisomerases (TOP2) IIα/IIβ. The compound demonstrates a selectivity index greater than 2 across all squamous cell carcinoma (SCC) cell lines. RSK2/TOP2-IN-1 induces apoptosis, autophagy, and the production of reactive oxygen species (ROS). It is applicable in cancer research, particularly for squamous cell carcinoma.

RSK2/TOP2-IN-1 (Compound 7e) demonstrates potent cytotoxicity against oral squamous cell carcinoma (SCC-4, SCC-9, SCC-25) cells with IC50 values of 57.1, 46.5, and 13.0 μM, respectively. It inhibits colorectal cancer HCT-116 cells, liver cancer HepG2 cells, and melanoma B16-F10 cells, with IC50 values of 9.1, 3.4, and 7.5 μM. At a concentration of 500 μM for 24 hours, it shows less than 2% hemolysis in red blood cells. The compound at 93 μM for 24 hours induces apoptosis in SCC-9 cells and at 46.5 μM for 48 hours, it promotes the formation of LC3-positive autophagosomes in SCC-9-LC3-GFP cells. Additionally, at concentrations of 93 μM for 24-72 hours, it induces reactive oxygen species production in SCC-9 cells. RSK2/TOP2-IN-1 at 2.91 μM for 72 hours inhibits the migration of SCC-9 cells, resulting in a 54.7% wound closure rate.

Compound 7e (RSK2/TOP2-IN-1), administered intraperitoneally as a single dose (100-400 mg/kg), did not result in mortality or weight loss in C57BL/6 mice.