Figure 3From: Cancer-initiating cells derived from established cervical cell lines exhibit stem-cell markers and increased radioresistance A side population (SP) is present in HeLa and SiHa cell lines. Flow cytometry trace from cervical cell preparation incubated for 90 min at 37°C with Hoechst dye as previously described by Goodell et al. (1996). Delimited red region is the (SP) fraction with and without VerapamilBack to article page