Table 2 Combination index (CI) values of sorafenib and 5-fluorouracil (5-FU) combination in different treatment sequences in hepatocellular carcinoma (HCC) cells

1

0.5

4.33 ± 1.73

32.84 ± 4.26

3.88 ± 1.73

112.45 ± 28.23

67.40 ± 15.67

13.63 ± 9.81

2

1

2.07 ± 0.44

9.70 ± 3.96

5.20 ± 2.17

1.95 ± 1.01

13.50 ± 9.43

0.50 ± 0.34

4

2

1.47 ± 0.25

3.69 ± 2.08

3.25 ± 2.57

1.33 ± 0.38

1.80 ± 0.11

0.41 ± 0.20

8

4

1.18 ± 0.28

2.33 ± 1.24

1.13 ± 0.27

1.45 ± 0.33

1.66 ± 0.17

0.38 ± 0.05

16

8

0.99 ± 0.40

1.26 ± 0.30

0.75 ± 0.15

1.02 ± 0.09

1.71 ± 0.06

0.40 ± 0.04