A Case-control Study On The Relationship Between Folic Acid And Some Indicators Associated With Folic Acid To Esophageal Carcinoma In Kazakh Populations

Objective: By analyzing the dietary nutrients intake, folic acid and other related indicators in the blood of esophageal carcinoma patients and control group in Kazakh in Xinjiang, to explore influencing factors which caused esophageal carcinoma and provide theoretical basis for prevention and treatment of esophageal carcinoma. Methods: By case-control study, Kazak residents(192 case of esophageal carcinoma, 200 case of control group) was interviewed with a food frequency questionnaires(FFQ). Automated chemiluminescence immunoassay were used to measure serum folic acid levels, serum vitamin B12 levels; the enzyme-inked immunosorbent assay(ELISA) was used to observe the serum DNMT1 levels; methylation specific PCR(MSP) was used to measure FHIT genes DNA methylation. Results: 1. In esophageal carcinoma group, the intake of proteins, vitamin A, thiamin, riboflavin, vitamin B6, folic acid, vitamin C, vitamin E were lower than the control group, and the differences were statistically significant(P<0.05). 2. The levels of serum folic acid and serum vitamin B12 in esophageal carcinoma group’s were lower than control group(z=-9.13, P=0.000; z=-6.06, P=0.000), and the levels of serum DNMT1 were higher(z=- 5.37, P=0.000). 3. Drinking(χ2=4.844, P=0.028, OR=2.670, 95% CI: 1.113~6.402), eat dry food(χ2=4.246, P=0.039, OR=2.287, 95% CI: 1.041~5.022), eat smoked meat(χ2=25.845, P=0.000, OR=12.812, 95% CI: 4.793~34.248), serum DNMT1 levels(χ2=5.509, P=0.019, OR=3.191, 95% CI:1.211~8.411) were risk factors of esophageal carcinoma; educational level(χ2=20.658, P=0.000, OR=0.150, 95% CI: 0.066~0.340), income(χ2=13.052, P=0.000, OR=0.208, 95% CI: 0.089~0.488), eat fresh vegetables(χ2=16.631, P=0.000, OR=0.181, 95% CI: 0.079~0.411), meals on time(χ2=18.404, P=0.000, OR=0.034, 95% CI: 0.007~0.160), serum folate levels(χ2=22.874, P=0.000, OR=0.021, 95% CI: 0.004~0.101) were protection factors of esophageal carcinoma. 4. There was a significant difference in the DNA methylation frequency of FHIT among the esophageal carcinoma and control groups(χ2=8.711, P=0.003). Conclusions:1. The risk factors of esophageal carcinoma may be eat less fresh vegetables, low education, low economic income, drinking, eat dry food, eat smoked meat, three meals are not on time, lower levels of serum folic acid, higher levels of serum DNMT1. 2. Kazakh esophageal carcinoma patients has a serious shortage of folic acid. With the levels of serum folic acid elevating, the risk of esophageal carcinoma would be reduced; with the levels of serum DNMT1 elevating, the risk of esophageal carcinoma would be increased. 3. The FHIT genes methylation was closely related for the occurrence of esophageal carcinoma in Kazak patients in Xinjiang.