Polymorphism in the interleukin-17A promoter contributes to gastric cancer

Table 1 Demographic data of the gastric cancer patients and healthy controls

	Gastric cancer (n = 161)	Control (n = 171)	P-value1
Age (yr)	62.56 ± 12.44	60.81 ± 12.76	0.21
Sex (M/F)	89/72	84/87	0.16
Marital status
Single	8 (5)	3 (1.8)
Married	149 (92.5)	166 (97.1)	0.002
Divorced	4 (2.5)	2 (1.2)
Occupation
Unemployed	4 (2.5)	1 (0.6)	0.003
Employed	24 (14.9)	35 (20.5)
Housewife	48 (29.8)	75 (43.9)
Other	85 (52.8)	60 (35.1)
Education 12 yr	53 (32.9)	85 (49.7)	0.003

¹Significance of categorical variables was assessed using the χ² test; Differences in age were evaluated using the Student t-test. Percentages are shown in parentheses. “Other” is defined as an occupation that does not fall into one of the defined groups.

Table 2 Frequency of the distribution of the G-197A (rs2275913) polymorphism of the interleukin-17A gene in gastric cancer patients and healthy controls n (%)

Genotype	Cancer (n = 161)	Controls (n = 171)	OR	CI	P-value1
GG	56 (34.8)	78 (45.6)	1.002
GA	61 (37.9)	72 (42.1)	1.2	0.73-1.91	0.53
AA	44 (27.3)	21 (12.3)	2.92	1.56-5.4	0.001
G allele	173 (53.7)	228 (66.7)	1.002
A allele	149 (46.3)	114 (33.3)	1.72	1.26-2.36	0.001
A allele carriage (AA + GA vs GG)	105 (64.2)	93 (54.4)	1.57	1.01-2.45	0.04

Genotype frequencies are indicated in absolute values, with the percentage in parentheses. G allele and A allele indicates the total number of each individual allele within each group.

¹Two-sided χ²-test;

²The first allele or genotype is considered as the reference for this analysis. OR: Odds ratio.

Table 3 Effect of G-197A polymorphism on gastric cancer development n (%)

	GA + AA	GG	OR	95%CI	P-value2
Age
< 50 yr	18 (17.1)	4 (7.1)	2.7	0.8-8.4	0.09
≥ 50 yr	87 (82.9)	52 (92.9)
Gender
Male	51 (48.6)	21 (37.5)	1.6	0.8-3.05	0.19
Female	54 (51.4)	35 (62.5)
H. pylori+	65 (61.9)	33 (58.9)	0.88	0.45-1.71	0.74
H. pylori-	40 (38.1)	23 (41.1)
TNM stage1
I-II	22 (55)	6 (16.2)	6.3	2.2-18.5	0.001
III-IV	18 (45)	31 (83.8)
Tumor differentiation
Well	25 (23.8)	9 (16.1)	1.003
Moderate	57 (54.3)	35 (62.5)	0.56	0.24-1.34	0.19
Poor	23 (21.9)	12 (21.4)	0.66	0.23-1.86	0.43

¹Data presented for 77 patients;

²All comparisons between categorical variables were made using a two-sided χ² test;

³Used as reference for tumor differentiation analyses. Values in parentheses indicate the percentage. H. pylori: Helicobacter pylori; TNM: Tumor, node, metastasis.