[Serum level and genotype of interleukin-6 in patients with esophageal cancer].
OBJECTIVE
To investigate the polymorphism of the interleukin-6 (IL-6) gene promoter-572C/G and -634C/G in patients with esophageal cancer, and to study the relation between the serum level and genotype of interleukin-6 and esophageal cancer.


METHODS
Peripheral blood samples were collected from 118 patients with esophageal cancer and 130 healthy persons as controls. The polymorphism of IL-6 was detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The serum level of IL-6 was determined by enzyme-linked immunosorbent assay (ELISA).


RESULTS
The frequency of the genotype GG of the IL-6 (-634) site in the cancer group was 12.7%, significantly higher that that of the control group (3.8%, P<0.05). The risk of esophageal cancer of the G allele carriers was 1.759 times that of the C allele carriers (OR=1.759, 95% CI=1.150-2.691). The serum level of IL-6 of the esophageal cancer group was (16.9+/-5.3) ng/L, significantly higher than that of the control group [(4.6+/-2.6) ng/L, P<0.01]. The serum level of IL-6 of the esophageal cancer with the G allele carriers was (18.8+/-6.1) ng/L, significantly higher than that of the esophageal cancer without the G allele carriers [(13.2+/-6.0) ng/L, P<0.01]. There was no significant difference in the distribution of the IL-6 gene-572C/G polymorphism between the 2 groups (P>0.05).


CONCLUSIONS
IL-6 gene-634C/G polymorphism is associated with the esophageal cancer. The IL-6 allele G carriers may be at increased risk of the esophageal cancer because of the increase of the IL-6 expression.
Department of Clinical Laboratory Medicine, Affiliated Hospital of Youjiang Medical College for Nationality, Baise 533000, China.
Ren-guang
RG
Tang
Ye-sheng
YS
Wei
Hong-ming
HM
Chen
Wen-zhu
WZ
Fang
Xian-ke
XK
Long
Xi-hua
XH
Yuan
D000328:Adult; D000368:Aged; D000483:Alleles; D004797:Enzyme-Linked Immunosorbent Assay; D004938:Esophageal Neoplasms / Q000097:blood / Q000235:genetics / Q000473:pathology*; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D015850:Interleukin-6 / Q000097:blood* / Q000235:genetics*; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D012150:Polymorphism, Restriction Fragment Length
D015850:Interleukin-6