Synergistic combinations of anti-cancer compounds can provide therapeutic benefits by producing better efficacy at potentially lower doses. SR16388, a novel steroidal compound that inhibits estrogen and estrogen-related receptors, has previously been shown to inhibit the proliferation and viability of diverse human cancer cell lines in vitro and to reduce the growth of several types of human xenograft tumors in mice, including, NSCLC and androgen-independent prostate cancer. We examined the two-drug combination effects of SR16388 in cell culture systems using a panel of approved cancer drugs with different mechanisms-of-action. Sixty cancer cell lines were treated with compounds alone or in combination for three days and CellTiter-Glo® Luminescent Cell Viability Assay (Promega Corp.) was used as the endpoint to measure cell viability. Combinations of SR16388 with anti-mitotic drugs Paclitaxel or Vincristine demonstrated synergistic effects on cell killing in multiple cell lines. These synergistic effects were further evaluated by calculating combination-index values using CalcuSyn software (Biosoft, Cambridge, UK)”. Studies are ongoing to elucidate the mechanisms that may lead the synergistic interaction of SR16388 and these antimitotic drugs.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr C178.