Table 1.

Mechanism of action and GI₅₀ values of agents used

Cmpd	Mechanism of Action	U2OS GI50 (μM)		Ref
		Mean	SD
V158411	Chk1 Inhibitor	0.82	0.1	[11]
VX-970	ATR Inhibitor	3.5	0.77	[50]
AZD1775	Wee1 Inhibitor	0.27	0.036	[51]
Gemcitabine	Chain terminator & RNR inhibitor	0.012	0.001
Camptothecin	Topo I inhibitor	0.25	0.003
Etoposide	Topo II inhibitor	4.2	0.32
LY2603618	Chk1 inhibitor	0.67	0.05	[52]
MK8776	Chk1 inhibitor	0.82	0.05	[53]
PF-477736	Chk1 inhibitor	0.71	0.06	[54]
Cisplatin	DNA alkylator	7.5	0.77
Hydroxyurea	RNR inhibitor	2800	1100
KU-60019	ATM inhibitor	24	9.2	[55]
NU7746	DNA-PKcs inhibitor	8.6	0.48	[56]