A Functional Polymorphism in the Promoter Region of Interleukin-12B Increases the Risk of Colorectal Cancer

Abstract EN

Objective.

To investigate whether the polymorphisms of interleukin-12B (IL-12B) were associated with the risk of developing colorectal cancer (CRC).

Patients and Methods.

Genotypes of rs17860508 and rs3212227 were determined by polymerase chain reaction with a direct sequencing method in 329 CRC patients and 342 matched healthy control subjects.

The expression of IL-12B mRNA was determined by RT-qPCR in 50 pairs of CRC tissues and their adjacent normal tissues.

Results.

Compared with TTAGAG/TTAGAG genotype of rs17860508, the GC/GC and TTAGAG/GC genotypes may significantly increase the risk of CRC (OR = 1.81, 95% CI = 1.18–2.78; OR = 1.46, 95% CI = 1.01–2.12, respectively).

Furthermore, the mRNA levels of IL-12B were significantly higher in the CRC tissues from patients with the rs17860508 GC/GC genotype than those with the TTAGAG/GC (P=0.009) and TTAGAG/TTAGAG (P=0.001) genotypes.

Conclusion.

These data suggested that the rs17860508 GC/GC genotype might upregulate IL-12B expression at the transcriptional level and thus increase the risk of CRC.