The Association Between Serum Levels Of Folate,Vitamin B12,Homocysteine And Risk Of Esophagus Cancers

Objective There are many studies about relationship folate and occurance of cancer these years. Folate deficiency is thought to contribute to carcinogenesis through disruption of DNA methylation or impaired DNA repair. Homocysteine is the biomethical product of folate metabolism, Vitamin B12 is the co- enzyme in the reaction. So there is a close relationship in Folate,Vitamin B12 and homocysteine. The purpose of this study is to evaluate the association between serum levels of folate,vitamin B12 and homocysteine and risk of esophagus cancer.Methods The study subjects were 63 male patients with esophagus cancer aged between 51-77 years. And 63 male healthy controls aged between 50-78 years. All the patients were diagnosed by CT and pathology. Healthy controls were derived from person who had undergone healthy examination in the same hospital. All the subjects were consecutively recruited from 2006.8 to 2007.5 . There is no supply of the drugs which might affect serum levels of folate,vitamin B12 and homocysteine in threre months before the recruitment. Serum folate,vitamin B12 and homocysteine levels were determined on blood samples obtained on the entry of the study. we compared the difference of these chemicals in esophagus cancer group and health control group through statistical methods. To evaluate the relationship between risk of esophagus cancer and these chemicals.Results The level of folate was significantly elevated in healthy control (7.65±2.824 ng/ml) than in esophagus cancer(5.85±2.380 ng/ml). While Serum homocysteine levels in patients with esophagus cancer (11.7±3.280umol/l) were significantly higher than that in healthy control group(9.2±1.745 umol/l). The level of vitamin B12 was lower in healthy control(269±55.493 pg/ml) than in esophagus cancer(312±89.607 pg/ml) too. Correlation analysis disclosed that serum folate is negatived correlated with homocysteine(r=-0.599 in healthy control group,r=-0.591 in esophagus cancer group) while there was no correlation between folate and vitamin B12,vitamin B12 and homocysteine. Analyzed with logistic regression we found that males with the lowest tertile of folate,homocysteine,vitamin B12 compared with males with the highest tertile,The odds ratios(OR) were 0.28(95% CI 0.11-0.72, P =0.008); 4.62(95% CI 1.74-12.25, P =0.002); 2.61(95 %CI 1.08-6.30, P =0.032) for esophagus cancer .Low level of serum folate was associated with high accidence of esophagus cancer. Serum homocysteine and vitamin B12 were significantly and positively correlated with risk of esophagus cancer.Conclusions Serum concentration of folate is inversely with risk of esophagus cancer, whereas homocysteine and vitamin B12 are directly associated with risk of esophagus cancer. The level of folate is much lower in esophagus cancer than in healthy control, but levels of vitamin B12 and homocysteine are evidently higher in esophagus cancer than in healthy control. There is a negatived correlation between serum folate and homocysteine,while there is no corelation between folate and vitamin B12,vitamin B12 and homocysteine.