Toll-like receptor (TLR) and nucleosome-binding oligomerization domain (NOD) gene polymorphisms and endometrial cancer risk.
BACKGROUND
Endometrial cancer is the most common gynaecological malignancy in women of developed countries. Many risk factors implicated in endometrial cancer trigger inflammatory events; therefore, alterations in immune response may predispose an individual to disease. Toll-like receptors (TLRs) and nucleosome-binding oligomerization domain (NOD) genes are integral to the recognition of pathogens and are highly polymorphic. For these reasons, the aim of the study was to assess the frequency of polymorphic variants in TLR and NOD genes in an Australian endometrial cancer population.


METHODS
Ten polymorphisms were genotyped in 191 endometrial cancer cases and 291 controls using real-time PCR: NOD1 (rs2075822, rs2907749, rs2907748), NOD2 (rs5743260, rs2066844, rs2066845), TLR2 (rs5743708), TLR4 (rs4986790) and TLR9 (rs5743836, rs187084).


RESULTS
Haplotype analysis revealed that the combination of the variant alleles of the two TLR9 polymorphisms, rs5743836 and rs187084, were protective for endometrial cancer risk: OR 0.11, 95% CI (0.03-0.44), p = 0.002. This result remained highly significant after adjustment for endometrial cancer risk factors and Bonferroni correction for multiple testing. There were no other associations observed for the other polymorphisms in TLR2, TLR4, NOD1 and NOD2.


CONCLUSIONS
The variant 'C' allele of rs5743836 causes greater TLR9 transcriptional activity compared to the 'T' allele, therefore, higher TLR9 activity may be related to efficient removal of microbial pathogens within the endometrium. Clearly, the association of these TLR9 polymorphisms and endometrial cancer risk must be further examined in an independent population. The results point towards the importance of examining immune response in endometrial tumourigenesis to understand new pathways that may be implicated in disease.
Ashton
Katie A
KA
Discipline of Medical Genetics, School of Biomedical Sciences, Faculty of Health, University of Newcastle, Australia.
Proietto
Anthony
A
Otton
Geoffrey
G
Symonds
Ian
I
McEvoy
Mark
M
Attia
John
J
Scott
Rodney J
RJ
D000368:Aged; D001315:Australia; D016022:Case-Control Studies; D016889:Endometrial Neoplasms / Q000235:genetics* / Q000473:pathology; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006239:Haplotypes / Q000235:genetics; D006801:Humans; D015810:Linkage Disequilibrium; D008875:Middle Aged; D053474:Nod1 Signaling Adaptor Protein / Q000235:genetics*; D053473:Nod2 Signaling Adaptor Protein / Q000235:genetics*; D011110:Polymorphism, Genetic / Q000235:genetics*; D011379:Prognosis; D012307:Risk Factors; D015996:Survival Rate; D051195:Toll-Like Receptor 2 / Q000235:genetics*; D051197:Toll-Like Receptor 4 / Q000235:genetics*; D051217:Toll-Like Receptor 9 / Q000235:genetics*
C119067:NOD1 protein, human; C429018:NOD2 protein, human; D053474:Nod1 Signaling Adaptor Protein; D053473:Nod2 Signaling Adaptor Protein; C495342:TLR2 protein, human; C495345:TLR4 protein, human; C495371:TLR9 protein, human; D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4; D051217:Toll-Like Receptor 9