Mechanisms of different response to ionizing irradiation in isogenic head and neck cancer cell lines

Radiation Oncology

Table 4 DNA damage signaling gene expression in 5 Gy-irradited radioresistant FaDu-RR cells and 5 Gy-irradiated radiosenstive 2A3 cells compared to 5 Gy-irradiated parental FaDu cells

Gene^a	FaDu-RR^b	P value^c	2A3^d	P value^c	DNA damage signaling pathways
APEX1			1.89	0.001	BER
ATM			1.87	0.01	ATM/ATR signaling, DSB repair, apoptosis, cell cycle
BAX			−2.49	0.006	apoptosis
BBC3			−3.65	0.003	apoptosis
BLM	−1.69	0.02	−7.86	0.000	DSB repair
BRIP1			−2.35	0.02	Other repair genes
CDC25A			−1.59	0.006	ATM/ATR signaling, cell cycle
CHEK2			−1.65	0.02	ATM/ATR signaling, other repair genes, apoptosis, cell cycle
CIB1			−5.60	0.001	Other repair genes, apoptosis
FANCA			−2.02	0.001	Other repair genes
HUS1			−1.65	0.001	ATM/ATR signaling, DSB repair
MDC1			−1.66	0.000	DSB repair, cell cycle
MLH1			1.51	0.02	DSB repair, mismatch repair
MPG			−1.85	0.04	BER
NBN			−1.83	0.02	DSB repair
NTHL1			−1.54	0.02	BER
PNKP			−2.77	0.000	NER
RBBP8			1.53	0.02	ATM/ATR signaling, other DNA repair genes
RNF168			−2.77	0.001	ATM/ATR signalling, other DNA repair genes
RPA1			−1.70	0.04	NER, DSB repair
SMC1A			−1.53	0.005	ATM/ATR signalling, other DNA repair genes
SUMO1			−2.73	0.002	Other DNA repair genes
TP73			−2.12	0.04	Mismatch repair, apoptosis, cell cycle
XPA	2.28	0.004	−1.54	0.03	NER
XRCC3			−2.20	0.01	other DNA repair genes

^a Gene symbol according to HUGO Gene Nomenclature Committee; ^b Fold regulation in gene expression in 5 Gy-irradiated FaDu-RR cells in comparison to 5 Gy-irradiated FaDu cells. Positive fold regulation values indicate gene over-expression, negative fold regulation values indicate gene under-expression; ^c The P values were calculated based on a Student’s t-test of the replicate 2^{(− ΔΔ CT)} values for each gene in the 5 Gy-irradiated and non-irradiated cells, and differences in gene expression were considered significant for P values less than 0.05. ^d Fold regulation in gene expression in 5 Gy-irradiated 2A3 cells in comparison to 5 Gy-irradiated FaDu cells. DSB double-strand break, BER base excision repair, NER nucleotide excision repair

ISSN: 1748-717X