TP53 Arg72Pro polymorphism is associated with esophageal cancer risk: A meta-analysis

Table 1 Main characteristics of included studies in the meta-analysis

First author (yr)	Country	Ethnicity	Source of controls	Specimens	Sample size (case/control)
Lee[20] (2000)	China (Taiwan)	Asian	Hospital	White blood cells	90/254
Peixoto[21] (2001)	China	Asian	Population	Exfoliated esophageal cells	32/57
Hamajima[22] (2002)	Japan	Asian	Hospital	White blood cells	102/241
Li[23] (2002)	China	Asian	Population/blood donors	Tumor tissue	62/131
Hu[24] (2003)	China	Asian	Population	White blood cells	120/130
Vos[25] (2003)	South Africa	African	Unknown	Tumor tissue, White blood cells	73/115
Hong[26] (2005)	China	Asian	Population	Normal Esophageal tissue	758/1420
Cai[27] (2006)	China	Asian	Population	White blood cells	204/389
Shao[28] (2008)	China	Asian	Population	White blood cells	673/694

Table 2 Distribution of TP53 Arg72Pro genotypes among esophageal cancer cases and controls included in the meta-analysis n (%)

First author (yr)	Cases			Controls
	Arg/Arg	Arg/Pro	Pro/Pro	Arg/Arg	Arg/Pro	Pro/Pro
Lee[20] (2000)	20 (22.2)	46 (51.1)	24 (26.7)	94 (37)	116 (45.7)	44 (17.3)
Peixoto[21] (2001)	8 (25)	13 (40.6)	11 (34.4)	9 (15.8)	24 (42.1)	24 (42.1)
Hamajima[22] (2002)	37 (36.3)	51 (50)	14 (13.7)	91 (37.8)	107 (44.4)	43 (17.8)
Li[23] (2002)	27 (43.5)	21 (33.9)	14 (22.6)	29 (22.1)	67 (51.1)	35 (26.7)
Hu[24] (2003)	29 (24.2)	60 (50)	32 (26.7)	38 (29.2)	68 (52.3)	24 (18.5)
Vos[25] (2003)	26 (35.6)	42 (57.5)	5 (6.8)	37 (32.2)	62 (53.9)	16 (13.9)
Hong[26] (2005)	199 (26.3)	340 (44.9)	219 (28.9)	425 (29.9)	731 (51.5)	264 (18.6)
Cai[27] (2006)	41 (20.1)	89 (43.6)	74 (36.3)	117 (30.1)	178 (45.8)	94 (24.2)
Shao[28] (2008)	163 (24.2)	306 (45.5)	204 (30.3)	195 (28.1)	366 (52.7)	133 (19.2)

Arg: Arginine; Pro: Proline.

Table 3 Results of meta-analysis for TP53 Arg72Pro polymorphism and esophageal cancer risk

Study groups	n1	Sample size(case/control)	Arg/Arg vs Pro/Pro			Arg/Arg+Arg/Pro vs Pro/Pro			Arg/Arg vs Arg/Pro+Pro/Pro
			OR (95% CI)	P2	P3	OR (95% CI)	P2	P3	OR (95% CI)	P2	P3
Total	9	2114/3431	0.76 (0.54-1.07)4	0.114	0.001	0.73 (0.57-0.94)4	0.014	0.009	0.89 (0.69-1.13)4	0.334	0.004
Source of controls
Population	5	1787/2690	0.56 (0.47-0.66)	< 0.001	0.273	0.57 (0.50-0.66)	< 0.001	0.404	0.80 (0.70-0.92)	0.001	0.324
Population/blood donors	1	62/131	2.33 (1.03-5.24)	0.041	-	1.25 (0.61-2.54)	0.538	-	2.71 (1.42-5.20)	0.003	-
Hospital	2	119/495	0.70 (0.22-2.18)4	0.533	0.022	0.80 (0.37-2.04)4	0.754	0.051	0.69 (0.36-1.31)4	0.252	0.08
Unknown	1	73/115	2.25 (0.73-6.91)	0.157	-	2.20 (0.77-6.28)	0.142	-	1.17 (0.63-2.16)	0.626	-
Specimen of cases
White blood cells or normal tissue	6	1947/3128	0.56 (0.47-0.65)	< 0.001	0.233	0.58 (0.51-0.67)	< 0.001	0.219	0.78 (0.68-0.88)	< 0.001	0.321
White blood cells/tumor tissue	1	73/115	2.25 (0.73-6.91)	0.157	-	2.20 (0.77-6.28)	0.142	-	1.17 (0.63-2.16)	0.626	-
Tumor tissue	1	62/131	2.33 (1.03-5.24)	0.041	-	1.25 (0.61-2.54)	0.538	-	2.71 (1.42-5.20)	0.003	-
Exfoliated esophageal cells	1	32/57	1.94 (0.59-6.38)	0.275	-	1.39 (0.56-3.41)	0.474	-	1.78 (0.61-5.19)	0.292	-
Sample size
≥ 200 subjects	6	1947/3128	0.56 (0.47-0.65)	< 0.001	0.233	0.58 (0.51-0.67)	< 0.001	0.219	0.78 (0.68-0.88)	< 0.001	0.321
< 200 subjects	3	167/303	2.21 (1.24-3.93)	0.007	0.969	1.47 (0.90-2.40)	0.121	0.677	1.73 (1.15-2.61)	0.009	0.182

¹Number of comparisons; ²P value for the association; ³P value for the heterogeneity;

⁴Random effects model was used when P value for heterogeneity test < 0.1, otherwise, fixed-effects model was used. Arg: Arginine; Pro: Proline; OR: Odds ratio.