X-ray repair cross-complementing group 1 polymorphisms and hepatocellular carcinoma: A meta-analysis

Table 1 Characteristics of eligible studies included in this study

Ref.	Country (ethnicity)	Genotyping method	Cases/controls	Source of controls	Type of controls	Polymorphisms of XRCC1 gene
Tang et al[26]	China (Asian)	PCR–RFLP	150/15	Hospital	Age matched, male and healthy	Arg194Trp, Arg280His, Arg399Gln
Bo et al[30]	China (Asian)	PCR–RFLP	130/130	Hospital	Age matched and healthy	Arg194Trp
Zeng et al[29]	China (Asian)	TaqMan SNP Genotyping	545/515	Hospital	Age, sex and residence matched and without cancer	Arg194Trp, Arg280His, Arg399Gln
Kiran et al[22]	India (Asian)	PCR–RFLP	63/155	Hospital	HBsAg (-), anti-HCV (-), and without renal or hepatic disease	Arg194Trp, Arg280His, Arg399Gln
Wu et al[27]	China (Asian)	PCR–RFLP	100/60	Hospital	Age and sex matched, healthy and HBsAg (-)	Arg280His
Ren et al[25]	China (Asian)	PCR–RFLP	50/92	Hospital	Healthy and HBsAg (-)	Arg399Gln
Borentain et al[20]	France (Caucasian)	Sequencing	56/89	Population	Healthy and without chronic liver disease	Arg399Gln
Kirk et al[23]	Gambia (African)	PCR–RFLP	195/352	Hospital	Age and sex matched, normal α-fetoprotein levels, and without clinical evidence of liver disease	Arg399Gln
Long et al[24]	China (Asian)	PCR–RFLP	140/536	Hospital	Age, sex and ethnicity matched and without cancer	Arg399Gln
Han et al[21]	China (Asian)	PCR–RFLP	69/136	Population	Age, sex and residence matched	Arg399Gln
Yu et al[28]	China (Asian)	PCR–RFLP	577/389	Population	Age and sex matched, HBsAg (+), and without HCC	Arg399Gln

XRCC1: X-ray repair cross-complementing group 1; PCR–RFLP: Polymerase chain reaction-restriction fragment length polymorphism; SNP: Single nucleotide polymorphism; HBsAg: Hepatitis B surface antigen; HCV: Hepatitis C virus; HCC: Hepatocellular carcinoma.

Table 2 Genotype distribution of X-ray repair cross-complementing group 1 polymorphisms used in this study

Polymorphism	Ref.	Ethnicity	Case			Control			HWE
Arg194Trp			Arg/Arg	Arg/Trp	Trp/Trp	Arg/Arg	Arg/Trp	Trp/Trp
	Tang et al[26]	Asian	94	41	15	81	58	11	0.88
	Bo et al[30]	Asian	94	31	5	116	12	2	0.02
	Zeng et al[29]	Asian	305	200	40	275	202	38	0.91
	Kiran et al[22]	Asian	8	43	12	27	64	52	0.35
Arg280His			Arg/Arg	Arg/His	His/His	Arg/Arg	Arg/His	His/His
	Tang et al[26]	Asian	138	11	1	123	26	1	0.76
	Zeng et al[29]	Asian	451	86	8	423	89	3	0.46
	Wu et al[27]	Asian	76	23	1	47	13	0	0.34
	Kiran et al[22]	Asian	19	30	14	91	29	35	0.00
Arg399Gln			Arg/Arg	Arg/Gln	Gln/Gln	Arg/Arg	Arg/Gln	Gln/Gln
	Tang et al[26]	Asian	41	94	15	84	54	12	0.43
	Zeng et al[29]	Asian	312	196	37	309	169	37	0.04
	Kiran et al[22]	Asian	25	33	5	45	70	27	0.98
	Ren et al[25]	Asian	32	14	4	46	41	5	0.28
	Borentain et al[20]	Caucasian	27	21	8	27	43	19	0.80
	Kirk et al[23]	African	160	31	4	300	48	4	0.19
	Long et al[24]	Asian	72	63	5	362	159	15	0.62
	Han et al[21]	Asian	34	28	7	58	63	15	0.73
	Yu et al[28]	Asian	301	223	53	218	143	28	0.49

HWE: Hardy-Weinberg equilibrium.

Table 3 Associations between Arg194Trp, Arg280His and Arg399Gln polymorphisms of X-ray repair cross-complementing group 1 gene and hepatocellular carcinoma risk shown in the meta-analysis

	n1	Cases/controls	OR (95% CI)	Significance (Z test)2		Heterogeneity (Q test)
				Z	P	Q	I2 (%)	P
Arg194Trp
All	4	888/938
Trp vs Arg			1.08 (0.73-1.60)	0.39	0.69	13.64	78.0	0.00
Trp/Trp vs Arg/Arg			1.03 (0.71-1.49)	0.17	0.86	2.18	0.0	0.53
Arg/Trp vs Arg/Arg			1.30 (0.68-2.48)	0.79	0.42	17.86	83.2	0.00
Trp/Trp vs Arg/Trp			0.88 (0.41-1.89)	0.31	0.75	9.95	69.9	0.01
Arg/Trp + Trp/Trp vs Arg/Arg			1.24 (0.70-2.20)	0.76	0.44	15.45	80.6	0.00
Trp/Trp vs Arg/Trp + Arg/Arg			0.93 (0.50-1.74)	0.21	0.83	7.45	59.7	0.05
Trp/Trp + Arg/Arg vs Arg/Trp			0.72 (0.36-1.43)	0.92	0.36	23.78	87.4	0.00
All HWE	3	758/808
Trp vs Arg			0.89 (0.76-1.05)	1.32	0.18	0.55	0.0	0.76
Trp/Trp vs Arg/Arg			0.96 (0.66-1.43)	0.18	0.85	0.39	0.0	0.82
Arg/Trp vs Arg/Arg			0.94 (0.56-1.60)	0.20	0.84	6.57	69.6	0.03
Trp/Trp vs Arg/Trp			0.87 (0.36-2.13)	0.29	0.77	9.95	79.9	0.00
Arg/Trp + Trp/Trp vs Arg/Arg			0.88 (0.72-1.09)	1.12	0.26	2.88	30.6	0.23
Trp/Trp vs Arg/Trp + Arg/Arg			0.83 (0.43-1.58)	0.56	0.57	5.86	65.9	0.05
Trp/Trp + Arg/Arg vs Arg/Trp			0.92 (0.47-1.81)	0.23	0.81	14.09	85.8	0.00
Arg280His
All	4	858/880
His vs Arg			1.03 (0.62-1.70)	0.11	0.90	12.73	76.4	0.00
His/His vs Arg/Arg			1.96 (1.03-3.75)	2.06	0.04	0.44	0.0	0.93
Arg/His vs Arg/Arg			1.16 (0.47-2.86)	0.33	0.74	26.36	88.6	0.00
His/His vs Arg/His			1.13 (0.30-4.22)	0.19	0.85	7.01	57.2	0.07
Arg/His + His/His vs Arg/Arg			1.10 (0.52-2.33)	0.25	0.80	20.16	85.1	0.00
His/His vs Arg/His + Arg/Arg			1.23 (0.69-2.21)	0.73	0.46	1.63	0.0	0.65
His/His + Arg/Arg vs Arg/His			0.90 (0.38-2.11)	0.23	0.81	24.71	87.9	0.00
All HWE	3	795/725
His vs Arg			0.83 (0.49-1.41)	0.67	0.50	5.44	63.2	0.06
His/His vs Arg/Arg			2.06 (0.67-6.25)	1.28	0.20	0.43	0.0	0.80
Arg/His vs Arg/Arg			0.74 (0.43-1.30)	1.03	0.30	5.08	60.6	0.07
His/His vs Arg/His			2.54 (0.80-8.04)	1.59	0.11	0.07	0.0	0.96
Arg/His + His/His vs Arg/Arg			0.78 (0.44-1.36)	0.86	0.39	5.40	63.0	0.06
His/His vs Arg/His + Arg/Arg			2.11 (0.69-6.43)	1.32	0.18	0.36	0.0	0.83
His/His + Arg/Arg vs Arg/His			1.34 (0.78-2.31)	1.07	0.28	4.95	59.6	0.08
Arg399Gln
All	9	1845/2401
Gln vs Arg			1.07 (0.84-1.34)	0.57	0.56	33.12	75.8	0.00
Gln/Gln vs Arg/Arg			1.05 (0.71-1.56)	0.29	0.77	14.84	46.1	0.06
Arg/Gln vs Arg/Arg			1.13 (0.80-1.57)	0.71	0.47	39.18	79.6	0.00
Gln/Gln vs Arg/Gln			0.93 (0.71-1.21)	0.52	0.60	6.32	0.0	0.61
Arg/Gln + Gln/Gln vs Arg/Arg			1.11 (0.80-1.54)	0.63	0.52	41.34	80.6	0.00
Gln/Gln vs Arg/Gln + Arg/Arg			1.00 (0.78-1.28)	0.03	0.97	7.87	0.0	0.44
Gln/Gln + Arg/Arg vs Arg/Gln			0.85 (0.63-1.15)	1.02	0.30	32.13	75.1	0.00
All HWE	8	1300/1886
Gln vs Arg			1.06 (0.79-1.41)	0.40	0.69	32.61	78.5	0.00
Gln/Gln vs Arg/Arg			1.06 (0.65-1.73)	0.25	0.80	14.61	52.1	0.04
Arg/Gln vs Arg/Arg			1.10 (0.73-1.68)	0.49	0.62	38.85	82.0	0.00
Gln/Gln vs Arg/Gln			0.96 (0.70-1.30)	0.25	0.79	6.15	0.0	0.52
Arg/Gln + Gln/Gln vs Arg/Arg			1.09 (0.72-1.64)	0.43	0.66	40.82	82.9	0.00
Gln/Gln vs Arg/Gln + Arg/Arg			1.02 (0.77-1.37)	0.19	0.84	7.72	9.3	0.35
Gln/Gln + Arg/Arg vs Arg/Gln			0.86 (0.60-1.24)	0.77	0.44	31.84	78.0	0.00
Asian	7	1594/1960
Gln vs Arg			1.12 (0.87-1.44)	0.89	0.37	25.85	76.8	0.00
Gln/Gln vs Arg/Arg			1.13 (0.86-1.48)	0.92	0.35	10.48	42.7	0.10
Arg/Gln vs Arg/Arg			1.22 (0.83-1.78)	1.04	0.29	33.10	81.9	0.00
Gln/Gln vs Arg/Gln			0.92 (0.69-1.21)	0.58	0.56	5.83	0.0	0.44
Arg/Gln + Gln/Gln vs Arg/Arg			1.20 (0.83-1.73)	0.98	0.32	33.84	82.3	0.00
Gln/Gln vs Arg/Gln + Arg/Arg			1.02 (0.79-1.33)	0.20	0.83	5.96	0.0	0.42
Gln/Gln + Arg/Arg vs Arg/Gln			0.81 (0.57-1.13)	1.21	0.22	28.55	79.0	0.00
Asian HWE	6	1049/1445
Gln vs Arg			1.12 (0.81-1.54)	0.69	0.49	24.80	79.8	0.00
Gln/Gln vs Arg/Arg			1.16 (0.69-1.97)	0.59	0.55	9.89	49.4	0.07
Arg/Gln vs Arg/Arg			1.22 (0.74-2.00)	0.78	0.43	32.23	84.5	0.00
Gln/Gln vs Arg/Gln			0.95 (0.68-1.32)	0.31	0.76	5.70	12.3	0.33
Arg/Gln + Gln/Gln vs Arg/Arg			1.20 (0.74-1.94)	0.75	0.45	32.66	84.7	0.00
Gln/Gln vs Arg/Gln + Arg/Arg			1.06 (0.78-1.46)	0.41	0.67	5.69	12.1	0.33
Gln/Gln + Arg/Arg vs Arg/Gln			0.80 (0.51-1.26)	0.93	0.35	27.84	82.0	0.00

¹Number of studies;

²Random-effects model was used when P value for heterogeneity test P < 0.1 or I² > 50%; otherwise, fixed-effects model was used. HWE: Hardy-Weinberg equilibrium; OR: Odds ratio.