Table 3 The uptake of CFP in HCT-116 cells is higher than in DLD-1 cells. CFP concentration in combination treatment with 5-FU was not different to single treatment in DLD-1 cells but was inhibited in HCT-116 cells. Concentrations of CFP when alone or combined with 5-FU, in cell lysates and supernatants (DLD-1 and HCT-116 cells) up to 8 h after treatment were measured by LC-MS/MS [26]. A) CFP (50 μg/ml) ± 5-FU (8 μM) in HCT-116 cells. B) CFP (50 μg/ml) ± 5-FU (16 μM) in DLD1 cells. p < 0.05 (CFP alone vs. in combination), n = 3

A)

DLD-1 cells

CFP alone (50 μg/ml)

CFP (50 μg/ml) + 5-FU (16 μM)

Pvalue

alone vs. combination

2 h

Supernatant

50.000 ± 1.697

49.261 ± 7.212

0.440

Lysate

0.012 ± 0.005

0.027 ± 0.006

0.059

4 h

Supernatant

54.187 ± 0.849

51.847 ± 4.879

0.251

Lysate

0.010 ± 0.0002

0.006 ± 0.006

0.192

6 h

Supernatant

45.813 ± 3.818

60.714 ± 9.970

0.069

Lysate

0.014 ± 0.0001

0.014 ± 0.001

0.138

8 h

Supernatant

47.947 ± 12.644

50.082 ± 4.371

0.377

Lysate

0.012 ± 0.001

0.015 ± 0.013

0.376

B)

HCT-116 cells

CFP alone (50 μg/ml)

CFP (50 μg/ml) + 5-FU (8 μM)

Pvalue

alone vs. combination

2 h

Supernatant

44.100 ± 3.395

42.900 ± 5.515

0.409

Lysate

0.018 ± 0.004

0.016 ± 0.001

0.305

4 h

Supernatant

34.500 ± 3.818

27.885 ± 2.440

0.087

Lysate

0.022 ± 0.005

0.016 ± 0.009

0.242

6 h

Supernatant

35.250 ± 1.485

34.400 ± 3.516

0.388

Lysate

0.050 ± 0.003

0.026 ± 0.001

0.005

8 h

Supernatant

35.850 ± 1.909

41.000 ± 5.679

0.161

Lysate

0.032 ± 0.002

0.007 ± 0.001

0.002