Sensitivities of Li-7 subpopulations to sorafenib. a) Sorafenib treatment (72 hr) selectively killed CD166(−) cells but not CD166(+) cells (WST-8 assay). b) FACS analysis of the bulk Li-7 cell population before (left) and after (right) sorafenib treatment (5 μM, 72 hr) confirmed selective killing of CD166(−) cells by sorafenib. c) Li-7 cells were more sensitive to sorafenib than other cell lines or Li-7 cells that have undergone 30 passages (WST-8). d) HCC lines other than Li-7 showed high expression of CD166 (FACS), which explains their resistance to sorafenib. e) Microarray analysis showed that FGF3, FGF4 and sorafenib-targeted genes are more highly expressed in CD166(−) cells than CD166(+) cells. f) Sequential treatment with 5-FU followed by sorafenib more effectively suppressed growth of Li-7 cells (P <0.01) than either alone (WST-8).