Human leukocyte antigen (HLA)-G gene polymorphism in patients with non-small cell lung cancer.

Background: Lung cancer represents the highest morbidity and mortality caused by neoplasms in the world; therefore researchers continue to search for new tools to diagnose and treat the disease. The aim of the study was to establish the role of single nucleotide polymorphisms (SNP) in the promoter region of the human leukocyte antigen (HLA)-G gene in patients with non-small cell lung cancer.

Methods: We enrolled 143 patients with a mean age of 63 years, diagnosed with non-small cell lung cancer, in the study. Adenocarcinomas made up 33% of the cases. Patients in stage III or IV of the tumor node metastasis staging system made up 59%. Two polymorphic sites in the promoter region of the HLA-G gene were genotyped (-725C>G>T and -716T>G).

Results: All genotyped SNPs were in Hardy-Weinberg equilibrium. No proof of a relationship between genotype -725C>G>T or -716T>G and the risk of lung cancer compared with healthy volunteers from the literature was found. We also found no correlation between the two SNPs and survival time, histological type of cancer, T stage, the presence of remote metastases or performance status according to the Eastern Cooperative Oncology Group (ECOG) scale. The only association we found was genotype -725C>G>T and the degree of lymph node metastases (N stage).

Conclusions: SNPs of the promoter of the HLA-G gene may have an impact on the development of lymph node metastases. In the study we did not prove a relationship between the examined SNPs and the course of the disease because of the small patient groups studied.