BIRC5 and cancer: To confirm a role for survivin in FL118 activity, we knocked down survivin using lentiviral survivin shRNA in HCT-8 cells and in contrast to the results in the low/no survivin-expressing non-cancerous cells, which showed no sensitivity to FL118 treatment (Fig. 2), we found that silencing of survivin in cancer cells increased the efficacy of FL118 in inhibiting cancer cell growth (Fig. 7a), demonstrating a role for survivin in modulating FL118 sensitivity, at least in these cancer type cells.