No abstract

IL-10 is a multifunctional cytokine with both immunosuppressive and antiangiogenic functions and may have both tumor-promoting and -inhibiting properties. A large number of polymorphisms (primarily single-nucleotide polymorphisms) have been identified in the IL10 gene promoter. Convincing evidence that certain of these polymorphisms are associated with differential expression of IL-10 in vitro and in some cases in vivo was obtained, and a number of studies investigated associations between IL10 polymorphisms and cancer susceptibility and prognosis. The results from 22 studies in 13 different malignancies are reviewed. In 17 of these studies, positive associations between IL10 genotype or haplotype and disease susceptibility, progression, or both were reported. In some of these cancers genotypes associated with low IL-10 expression were a risk factor for disease or disease progression, whereas in others genotypes associated with high IL-10 expression were a risk factor. Published findings in breast cancer are as yet conflicting. Most but not all of the studies reviewed are based on small sample sizes and a limited number of IL10 polymorphisms. However, the preliminary data indicate that larger studies are required in a number of cancers to confirm initial results, extend studies to include more detailed genotype and haplotype analysis, and combine genotype and gene expression studies in the same subjects. Such studies will contribute significantly to our understanding of the biological role of IL-10 in cancer development.

Interleukin-10 (IL-10) is a multifunctional cytokine with both immunosuppressive and anti-angiogenic functions and may have both tumour-promoting and -inhibiting properties. A large number of polymorphisms (primarily single nucleotide polymorphisms (SNPs)) have been identified in the IL-10 gene promoter. Convincing evidence that certain of these polymorphisms are associated with differential expression of IL-10 in vitro and in some cases in vivo has been obtained and a number of studies have investigated associations between IL-10 polymorphisms and cancer susceptibility/prognosis. The results from 22 studies in 13 different malignancies are reviewed. In 17 of these studies, positive associations between IL-10 genotype or haplotype and disease susceptibility and/or progression were reported. In some of these cancers genotypes associated with low IL-10 expression were a risk factor for disease or disease progression, while in others genotypes associated with high IL-10 expression were a risk factor. Published findings in breast cancer are as yet conflicting. Most, but not all of the studies reviewed are based on small sample sizes and a limited number of IL-10 polymorphisms. However, the preliminary data obtained thus far indicate that larger studies are required in a number of cancers, in order to confirm initial results, extend studies to include more detailed genotype/haplotype analysis and combine genotype and gene expression studies in the same subjects. Such studies will contribute significantly to our understanding of the biological role of IL-10 in cancer development.

There is a pro-inflammatory cytokine haplotype (IL-6 CC, IL-10 GG, TNFalpha AA) that is associated with adverse prognosis that may act, at least in part, through an inflammatory mediated mechanism. Determining patients' cytokine haplotype may improve prognostication and allow stratification for intervention studies.

Tumour growth in cutaneous malignant melanoma (CMM) is mediated by cell adhesion molecules, including intercellular adhesion molecule-1 (ICAM-1). ICAM-1 expression is associated with increasing Breslow thickness of vertical growth-phase tumours and, in patients with stage 1 disease, may be associated with disease free and patient survival. In this study we have investigated whether two single nucleotide polymorphisms (SNPs) in the ICAM-1 gene encoding amino acid substitutions in codons 241 and 469 of the expressed ICAM-1 molecule are associated with susceptibility to and markers of prognosis (including tumour Breslow thickness) in CMM. A total of 164 CMM patients and 264 cancer-free controls were genotyped for these SNPs by the 5' nuclease assay for allelic discrimination (TaqMan). No genotypes showed any significant associations with CMM susceptibility, although there was a non-significant increase in frequency of the ICAM-1 469 AA genotype among CMM patients vs. controls (38.4% vs. 29.9%; P = 0.11). However, the ICAM-1 241 GG genotype was significantly decreased in frequency among patients with primary invasive tumours of greater Breslow thickness (72.5% vs. 91.2%; P = 0.013; OR = 0.25 (0.072-0.85)). These results provide no evidence for a role for the ICAM-1 codon 241 and 469 SNPs in determining susceptibility to CMM, but provide preliminary evidence that the role of ICAM-1 polymorphism in modulating tumour growth in CMM requires further investigation in a larger study group.