Table I.

Radiobiological parameters in the different groups

Group	D0	Dq	SF2
MDA-MB-435
Untreated	2.093±0.131a	2.088±0.046	0.574±0.018a
siCTC1#3	1.475±0.153b	1.472±0.095b	0.417±0.016b
siNC	1.929±0.099	2.135±0.106	0.578±0.029
Mock	1.993±0.164	2.258±0.094	0.595±0.017
MDA-MB-435R
Untreated	3.266±0.072	2.379±0.108	0.701±0.016
siCTC1#3	2.356±0.109c	1.331±0.074c	0.565±0.031c
siNC	3.153±0.156	2.247±0.089	0.677±0.014
Mock	3.231±0.155	2.324±0.101	0.696±0.022

D₀, Dq and SF2 values were calculated according to the survival curves. D₀, the incremental dose required for reducing the fraction of colonies to 37%, indicative of single-event killing; Dq, quasi-threshold dose; SF2, the survival fraction of exponentially growing cells when irradiated at the clinically relevant dose of 2 Gy. Data are presented as the means ± SD of 3 independent experiments.

^aP<0.05 vs. untreated MDA-MB-435R cells;

^bP<0.05 and

^cP<0.05 vs. siNC and mock group, respectively. siNC groups showed no apparent differences with the mock groups.