Folate levels in mucosal tissue but not methylenetetrahydrofolate reductase polymorphisms are associated with gastric carcinogenesis

Table 3 MTHFR gene polymorphisms and the transcription of tumor-related genes

Genes	MTHFR	Upregulation n (%)	Normal (n)	Downregulation n (%)	mRNA ratio of cancerous to noncancerous tissue (mean ± SD)	P
p16INK4A	CC	1	3	10 (71.43)	0.63 ± 1.05	0.84
	CT	1	8	10 (52.63)	0.7 ± 0.88	0.69
	TT	0	2	3 (60)	0.85 ± 0.96	-
	AA	1	9	16 (61.54)	0.57 ± 0.96	0.51
	AC	1	4	7 (58.33)	0.81 ± 1.15	-
p21WAF1	CC	1	7	6 (42.86)	1.06 ± 1.06	-
	CT	1	5	13 (68.42)	0.47 ± 0.69	0.062
	TT	0	2	3 (60)	0.55 ± 0.55	0.32
	AA	2	10	14 (53.85)	0.75 ± 0.85	0.57
	AC	0	4	8 (66.67)	0.58 ± 0.85	-
c-myc	CC	6 (42.86)	7	1	2.26 ± 2.17	0.048
	CT	11 (57.89)	6	2	4.32 ± 3.25	-
	TT	2 (40)	2	1	2.15 ± 1.8	0.17
	AA	15 (57.69)	8	3	3.84 ± 3.17	0.076
	AC	4 (33.33)	7	1	2.06 ± 1.64	-
hMLH1	CC	0	3	11 (78.57)	0.46 ± 0.67	0.053
	CT	1	8	10 (52.63)	0.57 ± 0.82	0.13
	TT	0	3	1 (25)	1.3 ± 1.28	-
	AA	2	10	14 (53.85)	0.72 ± 0.96	0.28
	AC	0	4	8 (66.67)	0.39 ± 0.55	-
hMSH2	CC	0	5	9 (64.29)	0.31 ± 0.32	-
	CT	1	10	8 (42.11)	0.88 ± 0.97	0.04
	TT	0	3	2 (40)	0.94 ± 1.12	0.064
	AA	1	13	12 (46.15)	0.8 ± 0.98	0.19
	AC	0	5	7 (58.33)	0.4 ± 0.42	-