SP-1-39 is a novel colchicine-binding site inhibitor (CBSI), inhibits tubulin-polymerization, exhibits high cytotoxic activity in vitro with IC50 of 0.2 nM (PC-3/TxR).
SP-1-39 inhibits the proliferation of 2 HNSCC cell lines with low nanomolar IC50 values (1.4 to 2.1 nM), induces HNSCC cell apoptosis in a dose-dependent manner, interferes with migration of HNSCC cells, and leads to HNSCC cell cycle arrest in the G2/M phase.
SP-1-39 shows potential efficacy in a variety of cancer cell lines including breast, melanoma, pancreatic, and prostate.
SP-1-39 also shows abilities to overcome paclitaxel resistance in a paclitaxel-resistant prostate cancer xenograft model.
SP-1-39 suppresses the primary tumor growth of a Detroit 562 subcutaneous xenograft mouse model in 6- to 8-wk-old, male NSG (NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ) mice, with no detectable cytotoxic effects at a low dose of 2.5 mg/kg.