Heparin and Liver Heparan Sulfate Can Rescue Hepatoma Cells from Topotecan Action

Table 1

(a) Effect of heparin and TpT on cell cycle parameters of HepG2 and Hep3B cells (results of 3 independent experiments). Concentrations used: TpT 1 µM, heparin 100 µg/mL. TpT treatment resulted in significant alterations () of cell cycle parameters in both cell lines. Heparin did not change the cell cycle parameters (). S phase protection of heparin at combined treatment was statistically significant only in case of Hep3B cells. (b) Induction of apoptosis after TpT and heparin treatment. Proportion of dead/apoptotic cells after TpT and heparin treatment. Concentrations: TpT 1 µM, heparin 100 µg/mL. Values corresponding to the apoptosis gate of cell cycle represent the average of three experiments. TpT induced significant increase in apoptosis compared to the control in both cell lines. Heparin raised the proportion of apoptotic cells as compared to the controls for HepG2, but not for Hep3B cells. Significant decrease of dead cell fraction was found after a combined heparin and TpT treatment at both cell lines.

(a)

% of cells	HepG2			Hep3B
Treatment	G1	S	G2	G1	S	G2
Control	52,6 ± 4,08	35,7 ± 3,29	11,6 ± 2,19	78,7 ± 0,42	15,9 ± 0,14	5,5 ± 0,28
1 µM TpT	15,8 ± 1,3^1	80,8 ± 15,5^1	4,2 ± 0,07^1	2,06 ± 0,07^1	65,6 ± 0,99^1	13,7 ± 1,06^1
100 µg/mL Heparin	58,9 ± 1,39	28,3 ± 3,58	12,8 ± 0,59	81,1 ± 0,28	14 ± 0,28	5 ± 0,07
Hp + TpT	14,5 ± 0,45	70,2 ± 3,97^3	15,2 ± 0,68	35,4 ± 0,1	56,4 ± 2,33^2	8,1 ± 2,4

¹Student’s -test: for HepG2, for Hep3B (TpT compared to control).
²Student’s -test: (Hp + TpT compared to TpT alone).
³Student’s -test: (Hp + TpT compared to TpT alone).

(b)

%-of cells in apoptotic gate	HepG2	Hep3B
Control	5,65 ± 0,595	3,53 ± 0,93
1 µM TpT	18,67 ± 3,53^1
100 µg/mL heparin	9,06 ± 0,16^2	2,48 ± 0,22
Hp + TpT

¹Student’s -test: < 0,001 (TpT compared to control).
²Student’s -test: < 0,05 (Hp compared to control).
³Student’s -test: < 0,05 (Hp + TpT compared to TpT alone).