Association of cyclin D1 (G870A) polymorphism with susceptibility to esophageal and gastric cardiac carcinoma in a northern Chinese population

Genome-wide association study in esophageal cancer using GeneChip mapping 10K array

Whole genome association studies of complex human diseases represent a new paradigm in the postgenomic era. In this study, we report application of the Affymetrix, Inc. (Santa Clara, CA) high-density single nucleotide polymorphism (SNP) array containing 11,555 SNPs in a pilot case-control study of esophageal squamous cell carcinoma (ESCC) that included the analysis of germ line samples from 50 ESCC patients and 50 matched controls. The average genotyping call rate for the 100 samples analyzed was 96%. Using the generalized linear model (GLM) with adjustment for potential confounders and multiple comparisons, we identified 37 SNPs associated with disease, assuming a recessive mode of transmission; similarly, 48 SNPs were identified assuming a dominant mode and 53 SNPs in a continuous mode. When the 37 SNPs identified from the GLM recessive mode were used in a principal components analysis, the first principal component correctly predicted 46 of 50 cases and 47 of 50 controls. Among all the SNPs selected from GLMs for the three modes of transmission, 39 could be mapped to 1 of 33 genes. Many of these genes are involved in various cancers, including GASC1, shown previously to be amplified in ESCCs, and EPHB1 and PIK3C3. In conclusion, we have shown the feasibility of the Affymetrix 10K SNP array in genome-wide association studies of common cancers and identified new candidate loci to study in ESCC.

Cyclin D1 polymorphism and the risk of endometrial cancer

OBJECTIVES

The common G to A single nucleotide polymorphism (G870A) in the splice donor region of exon 4 enhances alternate splicing, and produces a longer half-life cyclin D1 (CCND1). This study was aimed at investigating the possible association between the G870A polymorphism in CCND1 and the risk of endometrial cancer.

METHODS

We assessed the association between the CCND1 G870A polymorphism and the risk of endometrial cancer in a hospital-based case-control study among 231 Korean women (77 cases; 154 matched controls). Controls were matched to cases with respect to age, menopausal status, and hormone therapy status.

RESULT

The allele frequencies of the case subjects (A, 0.45; G, 0.55) were significantly different from those of control subjects (A, 0.58; G, 0.42) (P = 0.008). All case and control subjects were in Hardy-Weinberg equilibrium. The AA genotype was associated with a significantly elevated odds ratio (OR) of 3.18 [95% confidence interval (CI) 1.38-7.37, P = 0.007], and the AG genotype was associated with an OR of 1.38 (95% CI 0.65-2.89). When we combined the GG and AG genotypes as a reference genotype, we found that the OR for the AA genotype was 2.53 (95% CI 1.34-4.80, P = 0.004), supporting a recessive model for the A allele. Conditional logistic regression adjusted for various risk factors of endometrial cancer revealed positive associations between the AA genotype and an increased risk of endometrial cancer (OR 3.16, 95% CI 1.18-8.43, P = 0.022). However, no significant difference in endometrial cancer stage or grade was observed between the CCND1 genotypes.

CONCLUSION

Our data suggest that the CCND1 polymorphism is associated with an increased risk of endometrial cancer. To validate this association, a large-scale population-based study is needed.

No association of the matrix metalloproteinase 1 promoter polymorphism with susceptibility to esophageal squamous cell carcinoma and gastric cardiac adenocarcinoma in northern China

AIM: To investigate association of the 2G or1G single nucleotide polymorphism (SNP) in matrix metalloproteinase 1 (MMP1) promoter with susceptibility to esophageal squam-ous cell carcinoma (ESCC) and gastric cardiac adenocarcinoma (GCA) in a population of North China.

METHODS: MMP1 promoter SNP was genotyped by polymerase-chain reaction (PCR)-restriction fragment length polymorphism (RFLP) analysis in 417 cancer patients (234 ESCC and 183 GCA) and 350 healthy controls.

RESULTS: The genotype frequencies of the MMP1 promoter SNP in healthy controls were 55.4% (2G/2G), 30% (1G/2G) and 14.6% (1G/1G), respectively. The genotype and allelotype distribution in ESCC and GCA patients was not significantly different from that in healthy controls (all P values were above 0.05). Compared with the 1G/1G genotype, neither the 2G/2G nor in combination with the 1G/2G genotype significantly modified the risk of developing ESCC and GCA, the adjusted odds ratio was 1.28 (95%CI = 0.78-2.09), 1.23 (95%CI = 0.38-2.05) in ESCC and 1.39 (95%CI = 0.80-2.41), 1.34 (95%CI = 0.74-2.40) in GCA, respectively. When stratified by smoking status and family history of upper gastrointestinal cancer, the 2G/2G genotype alone or in combination with the 1G/2G genotype also did not show any significant influence on the risk of ESCC and GCA development. In addition, influence of the MMP1 SNP on lymphatic metastasis in ESCC and GCA was also not obs-erved.

CONCLUSION: The 2G or 1G SNP in the MMP1 promoter might not modify the risk of ESCC and GCA development and might not be used as a stratification marker to predict the potential of lymphatic metastasis in these two tumor types.

The effect of cyclin D1 (CCND1) G870A-polymorphism on breast cancer risk is modified by oxidative stress among Chinese women in Singapore

Cyclin D1 (CCND1), an intracellular cell-cycle regulatory protein with checkpoint function, can promote cell proliferation or induce growth arrest and apoptosis depending on the cellular context. We hypothesized that the direction of the association between the (CCND1) G870A-polymorphism and breast cancer risk may be modified by dietary and genetic factors influencing the oxidant-antioxidant balance, such as a dietary pattern with a high intake of n-6 fatty acids and a low intake of n-3 fatty acids, or a genetic profile that is deficient in glutathione S-transferases. We tested our hypothesis in a case-control study nested into the Singapore Chinese Health Study, a prospective investigation of diet and cancer in 63,000 Chinese men and women. Genomic DNA collected from 258 incident cases of breast cancer and 670 female cohort controls was examined for CCND1, GSTM1, GSTT1 and GSTP1 genes using fluorogenic 5'-nuclease assay. Unconditional logistic regression models were used to assess the effects with adjustment for potential confounders. All statistical tests were two-sided. The heterozygous CCND1 GA genotype significantly reduced the breast cancer risk in all subjects (OR=0.67, 95% CI 0.45-0.99) when compared with the GG genotype. The association was restricted to women with a high (above median value) intake level of n-6 fatty acids (OR=0.51, 95% CI 0.30-0.87), a low (below median value) intake level of the antagonistic marine n-3 fatty acids (OR=0.54, 95% CI 0.32-0.93) or a total lack of the antioxidative GSTM1 (OR=0.44, 95% CI 0.25-0.80) or GSTT1 genes (OR=0.46, 95% CI 0.24-0.87). The effects were consistently stronger in cases with advanced disease. The AA genotype did not affect breast cancer risk. The results of this study are compatible with the hypothesis that the oxidant-antioxidant balance in cells is an important determinant of the direction of the cyclin D1 effect, leading either to cell proliferation or cell death.

Genetic polymorphisms of CYP2E1, GSTT1, GSTP1, GSTM1, ALDH2, and ODC and the risk of advanced precancerous gastric lesions in a Chinese population

There have been few studies of the associations of genetic polymorphisms with precancerous gastric lesions. We conducted a cross-sectional study to compare the prevalences of several genetic polymorphisms in 302 subjects with mild chronic atrophic gastritis with prevalences in 606 subjects with deep intestinal metaplasia or dysplasia. This stratified random sample of 908 subjects was selected and analyzed for genetic polymorphisms from 2,628 individuals who had gastric biopsies with histopathology in 1989 in Linqu County, Shandong Province, China. In subjects with mild chronic atrophic gastritis, the frequencies of the variant (less common) alleles of CYP2E1 RsaI, CYP2E1 DraI, GSTP1, ALDH2, and ODC were, respectively, 0.156, 0.201, 0.189, 0.190, and 0.428. The frequencies of the null genotypes of GSTM1 and GSTT1 in the mild chronic atrophic gastritis group were 0.509 and 0.565, respectively. Comparing mild chronic atrophic gastritis with deep intestinal metaplasia or any degree of dysplasia, we found no statistically significant associations with any genotype from these loci for dominant, additive, or recessive inheritance models. There was no statistically significant evidence of multiplicative interactions between any pair of genotypes based on CYP2E1 RsaI, CYP2E1 DraI, GSTP1, GSTM1, or GSTT1; nor between Helicobacter pylori status and any of these five loci; nor between smoking status and GSTP1, GSTM1, or GSTT1; nor between alcohol consumption and ALDH2. Statistically significant interactions were noted between salt consumption and GSTP1 and between sour pancake consumption and CYP2E1 RsaI. There was, moreover, a statistically significant interaction (odds ratio, 1.78; 95% confidence interval, 1.03-3.08) between CYP2E1 DraI and smoking at least one cigarette per day. A positive but not statistically significant interaction was also seen between CYP2E1 RsaI and smoking status. These polymorphisms do not seem to govern progression from mild chronic atrophic gastritis to advanced precancerous gastric lesions, but the effects of smoking may be accentuated in individuals carrying variants of CYP2E1.

Association of Cyclin D1 Genotype with Breast Cancer Risk and Survival

Cyclin D1 (CCND1) is a key cell cycle regulatory protein that governs cell cycle progression from the G1 to S phase. A common polymorphism (A870G) in exon 4 of the CCND1 gene produces an alternate transcript (transcript-b) that preferentially encodes a protein with enhanced cell transformation activity and possible prolonged half-life. We evaluated the association of CCND1 A870G polymorphism with breast cancer risk and survival in 1,130 breast cancer cases and 1,196 controls who participated in the Shanghai Breast Cancer Study. Approximately 81% of cases and 79% of controls carried the A allele at A870G of the CCND1 gene [odds ratio, 1.1; 95% confidence interval (95% CI), 0.9-1.4]. As lightly stronger but nonsignificant association was found for the A allele among younger women (odds ratio, 1.3; 95% CI, 0.9-1.8). However, this polymorphism seems to modify the effect of hormonal exposures on postmenopausal breast cancer, as the positive associations of postmenopausal breast cancer with body mass index (Pfor interaction = 0.02) and waist-to-hip ratios (P for interaction < 0.03; all Ps are two sided) were only observed among women who carry the A allele at A870G of the CCND1 gene. Following up with this cohort of patients for an average of 4.84 years, we found that the CCND1 A870G polymorphism was inversely associated with overall and disease-free survival, particularly among women with late stage or estrogen/progesterone receptor-negative breast cancer. The adjusted hazard ratios for disease-free survival associated with GA and AA genotypes were 0.94 (95% CI, 0.49-1.82) and 0.41 (95% CI, 0.19-0.91) for tumor-node-metastasis stage III to IV breast cancer, and 0.35 (95% CI, 0.15-0.80) and 0.32 (95% CI, 0.13-0.79) for estrogen/progesterone receptor-negative breast cancer. This study suggests that CCND1 A870G polymorphism may modify the postmenopausal breast cancer risk associated with hormonal exposure and predict survival after breast cancer diagnosis.