Common genetic variation in adiponectin, leptin, and leptin receptor and association with breast cancer subtypes

Adipocytokines are produced by visceral fat, and levels may be associated with breast cancer risk. We investigated whether single nucleotide polymorphisms (SNPs) in adipocytokine genes adiponectin (ADIPOQ), leptin (LEP), and the leptin receptor (LEPR) were associated with basal-like or luminal A breast cancer subtypes. 104 candidate and tag SNPs were genotyped in 1776 of 2022 controls and 1972 (200 basal-like, 679 luminal A) of 2311 cases from the Carolina Breast Cancer Study (CBCS), a population-based case–control study of whites and African Americans. Breast cancer molecular subtypes were determined by immunohistochemistry. Genotype odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using unconditional logistic regression. Haplotype ORs and 95% CIs were estimated using Hapstat. Interactions with waist-hip ratio were evaluated using a multiplicative interaction term. Ancestry was estimated from 144 ancestry informative markers (AIMs), and included in models to control for population stratification. Candidate SNPs LEPR K109R (rs1137100) and LEPR Q223R (rs1137101) were positively associated with luminal A breast cancer, whereas ADIPOQ +45 T/G (rs2241766), ADIPOQ +276 G/T (rs1501299), and LEPR K656N (rs8129183) were not associated with either subtype. Few patterns were observed among tag SNPs, with the exception of 3 LEPR SNPs (rs17412175, rs9436746, and rs9436748) that were in moderate LD and inversely associated with basal-like breast cancer. However, no SNP associations were statistically significant after adjustment for multiple comparisons. Haplotypes in LEP and LEPR were associated with both basal-like and luminal A subtypes. There was no evidence of interaction with waist-hip ratio. Data suggest associations between LEPR candidate SNPs and luminal A breast cancer in the CBCS and LEPR intron 2 tag SNPs and basal-like breast cancer. Replication in additional studies where breast cancer subtypes have been defined is necessary to confirm these potential associations.     

Leptin and leptin receptor genes in relation to premenopausal breast cancer incidence and grade in Caucasian women

Body mass is inversely related to breast cancer risk among premenopausal women. Leptin, an essential cytokine regulating food intake, energy expenditure, glucose, and fat metabolism may be part of the mechanistic pathway. We investigated 50 tagging and candidate SNPs in the leptin (LEP) and leptin receptor (LEPR) genes for associations with premenopausal breast cancer incidence using 405 cases and 810 controls nested within the Nurses’ Health Study II. We also examined associations between these SNPs and circulating leptin (among 910 women) and breast cancer grade (among 267 patients). Permutation tests were performed to adjust for multiple testing. We did not detect a significant association between SNPs in the LEP or LEPR gene and either breast cancer incidence or plasma leptin levels. Among cases, 14 SNPs of the LEPR gene were significantly associated with cancer grade, and rs1137101 (Q223R) survived multiple testing adjustment (adjusted P = 0.04). The G carriers of rs1137101 were more likely to have poorly differentiated than well-differentiated cancers. Our data suggest that common genetic variation in the LEP or LEPR gene has no strong association with premenopausal breast cancer risk. The LEPR gene might be associated with breast cancer grade.     

Adipokine genes and prostate cancer risk

Adiposity and adipocyte‐derived cytokines have been implicated in prostate carcinogenesis. However, the relationship of adipokine gene variants with prostate cancer risk has not been thoroughly investigated. We therefore examined common variants of the IL6, LEP, LEPR, TNF and ADIPOQ genes in relation to prostate cancer in a case‐control study nested within a large cohort of Finnish men. The study sample consisted of 1,053 cases of prostate cancer, diagnosed over an average 11 years of follow up, and 1,053 controls matched to the cases on age, intervention group and date of baseline blood draw. Logistic regression was used to model the relative odds of prostate cancer. We also examined genotypes in relation to serum insulin, IGF‐1 and IGF‐1:IGFBP‐3 among 196 controls. Variant alleles at three loci (?14858A>G, ?13973A>C, ?13736C>A) in a potential regulatory region of the LEP gene conferred a statistically significant 20% reduced risk of prostate cancer. For example, at the ?14858A>G locus, heterozygotes and homozygotes for the A allele had an odds ratio (OR) of prostate cancer of 0.76 [95% confidence interval (CI) 0.62, 0.93] and 0.79 (95% CI 0.60, 1.04), respectively. At 13288G>A, relative to the GG genotype, the AA genotype was associated with a suggestive increased risk of prostate cancer (OR = 1.29; 95% CI 0.99,1.67; p_trend = 0.05). Polymorphisms in the IL6, LEPR, TNF and ADIPOQ genes were not associated with prostate cancer. Allelic variants in the LEP gene are related to prostate cancer risk, supporting a role for leptin in prostate carcinogenesis. © 2008 Wiley‐Liss, Inc.     

Adiponectin pathway polymorphisms and risk of breast cancer in African Americans and Hispanics in the Women’s Health Initiative

Adiponectin, a protein secreted by the adipose tissue, is an endogenous insulin sensitizer with circulating levels that are decreased in obese and diabetic subjects. Recently, circulating levels of adiponectin have been correlated with breast cancer risk. Our previous work showed that polymorphisms of the adiponectin pathway are associated with breast cancer risk. We conducted the first study of adiponectin pathways in African Americans and Hispanics in the Women’s Health Initiative SNP Health Association Resource cohort of 3,642 self-identified Hispanic women and 8,515 self-identified African American women who provided consent for DNA analysis. Single nucleotide polymorphisms (SNPs) from three genes were included in this analysis: ADIPOQ, ADIPOR1, and ADIPOR2. The genome-wide human SNP array 6.0 (909,622 SNPs) (www.affymetrix.com) was used. We found that rs1501299, a functional SNP of ADIPOQ that we previously reported was associated with breast cancer risk in a mostly Caucasian population, was also significantly associated with breast cancer incidence (HR for the GG/TG genotype: 1.23; 95 % CI 1.059–1.43) in African American women. We did not find any other SNPs in these genes to be associated with breast cancer incidence. This is the first study assessing the role of adiponectin pathway SNPs in breast cancer risk in African Americans and Hispanics. RS1501299 is significantly associated with breast cancer risk in African American women. As the rates of obesity and diabetes increase in African Americans and Hispanics, adiponectin and its functional SNPs may aid in breast cancer risk assessment.     

Adiponectin gene and risk of colorectal cancer

Background:

Genes of the adiponectin pathway are interesting candidates for colorectal cancer risk based on the potential association between colorectal cancer and obesity. However, variants of the adiponectin gene (ADIPOQ) have been demonstrated to be inconsistently associated with risk of colorectal cancer.

Methods:

The current study attempted to evaluate these findings by examining several single nucleotide polymorphisms (SNPs) that were previously genotyped as part of a genome-wide association study in the ADIPOQ gene. Genotyping was also performed for a previously reported risk variant, rs266729, in 1062 individuals with a diagnosis of colorectal cancer and 1062 controls matched on age, gender and ethnicity (Jewish or not Jewish) as part of a population-based case–control study in Israel.

Results:

No evidence was found for an association between ADIPOQ and risk of colorectal cancer. The single nucleotide variant previously associated with decreased risk of colorectal cancer, rs266729, revealed an adjusted odds ratio of 1.04; 95% confidence interval, 0.88–1.23.

Conclusion:

The SNP, rs266729, was not strongly associated with colorectal cancer in patients of Ashkenazi Jewish descent or other ethnic groups in Israel.     

The adiponectin gene single-nucleotide polymorphism rs1501299 is associated with hepatocellular carcinoma risk

Purpose

Increasing lines of evidence have suggested that adiponectin, an adipocyte-derived hormone, plays an important role in the development of hepatocellular carcinoma (HCC). However, the relationship between genetic variants of the adiponectin gene (ADIPOQ) and HCC has not been previously explored. Therefore, we performed a case–control study to examine the association of haplotype-tagging single-nucleotide polymorphisms (SNPs) in ADIPOQ with HCC risk.

Methods

Five haplotype-tagging SNPs of ADIPOQ (rs266729, rs822395, rs822396, rs2241766 and rs1501299) were genotyped in 200 HCC patients and 200 non-HCC controls by PCR amplification and direct sequencing. Logistic regression was used to estimate the risk of HCC associated with each individual SNP and we adjusted for multiple testing by the Bonferroni correction.

Results

Of the five tested SNPs, rs1501299 showed a strong and significant association with HCC risk even after the Bonferroni correction. After adjusting for the serological status of the hepatitis virus B core antibody and for other SNPs, the odds ratios were 4.33 [95 % confidence interval (CI) 2.07–9.05; corrected P < 0.005] and 3.71 (95 % CI 1.84–7.48; corrected P < 0.005) for the GG genotype and GG/GT combined genotype, respectively, versus the TT genotype.

Conclusions

This is the first report, demonstrating an association of ADIPOQ polymorphisms with HCC risk. Our results implicate the ADIPOQ SNP rs1501299 as a susceptibility locus for HCC.     

The modifying effect of C-reactive protein gene polymorphisms on the association between central obesity and endometrial cancer risk

BACKGROUND.

Obesity is a major risk factor for endometrial cancer. Obesity, particularly central obesity, is considered as a systemic inflammatory condition and is related strongly to insulin resistance. C‐reactive protein (CRP) is the most recognized biologic marker of chronic systematic inflammation, and it is conceivable that the CRP gene may work together with obesity in the development of endometrial cancer.

METHODS.

On the basis of a population‐based case–control study in a Chinese population, the authors obtained obesity measurements and data on 6 CRP single‐nucleotide polymorphisms (SNPs) from 1046 patients with newly diagnosed endometrial cancer (cases) and from 1035 age frequency‐matched controls. The association of the CRP SNPs with endometrial cancer risk and their modification on the association between obesity and endometrial cancer risk were evaluated.

RESULTS.

Although CRP SNPs alone were not associated with endometrial cancer, the associations of endometrial cancer with central obesity, measured as the waist‐to‐hip ratio (WHR) and the waist circumference, seemed to be stronger in women who were homozygous for the major allele of reference SNP (rs)1130864 (cytidine [C]/C) than in women who had the C/thymidine (T) and T/T genotypes (interaction test: P = .013 for WHR; P = .083 for waist circumference). When the women were stratified further by menopausal status, the observed interactions persisted mainly in premenopausal women (interaction test: P < .001 for WHR; P = .002 for waist circumference).

CONCLUSIONS.

The current results suggested that, in the Chinese population that was studied, obesity‐related insulin resistance and proinflammatory effects may play an important role in endometrial cancer risk, and these effects were modified significantly by the CRP SNP rs1130864. Cancer 2008. © 2008 American Cancer Society.     

Association of the progesterone receptor gene with endometrial cancer risk in a Chinese population

BACKGROUND:

Single nucleotide polymorphisms (SNPs) in the progesterone receptor (PGR) gene have been associated with the risk of endometrial cancer. However, to the authors' knowledge, no study to date has systematically evaluated the role of the PGR gene in endometrial carcinogenesis.

METHODS:

Exposure information and DNA samples collected in the Shanghai Endometrial Cancer Study, a population‐based case‐control study of 1204 incident cases and 1212 age‐ and frequency‐matched population controls, were used in this study. Seven tag SNPs were identified for the PGR gene plus the 5‐kilobase (kb) flanking regions using the Han Chinese data from the HapMap project with a pairwise correlation coefficient (r²) ≥ 0.90. These 7 SNPs captured 92% of SNPs in the region with a pairwise r² ≥ 0.90 or 100% of SNPs with a pairwise r² ≥ 0.80. Genotyping of polymorphisms was performed by using the Affymetrix MegAllele Targeted Genotyping System. A logistic regression model was used to compute adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs).

RESULTS:

Of 7 tag SNPs that were assessed, 2 polymorphisms in the 3′ flanking region of the PGR gene, reference SNP identification number (rs) 11224561 (rs11224561) and rs471767, were associated with the risk of endometrial cancer. The cytosine/cytosine (CC) genotype of SNP rs11224561 was associated with decreased risk (OR, 0.68; 95% CI, 0.50‐0.92) compared with the thymine/thymine (TT) genotype. Carrying the guanine (G) allele of the rs471767 SNP also was associated with decreased risk, although the association was not statistically significant (OR, 0.78, 95%CI, 0.59‐1.04 and OR, 0.32, 95%CI, 0.03‐3.05 for the adenine [A]G and GG genotypes, respectively, compared with the homozygote AA).

CONCLUSIONS:

The current findings suggested that polymorphisms in the 3′ flanking region of the PGR gene may be associated with the risk of endometrial cancer. Cancer 2009. © 2009 American Cancer Society.     

Polymorphisms in three obesity-related genes (<Emphasis Type="Italic">LEP</Emphasis>, <Emphasis Type="Italic">LEPR</Emphasis>, and <Emphasis Type="Italic">PON1</Emphasis>) and breast cancer risk: a meta-analysis

Common genetic variations in the leptin (LEP), leptin receptor (LEPR), and paraoxonase 1 (PON1) genes have been considered to be implicated in the development of breast cancer. However, the results were inconsistent. In this study, a meta-analysis was performed to assess the associations of five polymorphisms, including LEP G2548A, LEPR Q223R, LEPR Lys109Arg, PON1 L55M, and PON1 Q192R polymorphisms, with breast cancer risk. Published literature from PubMed, ISI Web of Science, Embase databases, CNKI, and Wanfang Data were retrieved. All studies evaluating the association between LEP G2548A, LEPR Q223R, LEPR Lys109Arg, PON1 L55M, or PON1 Q192R polymorphism and breast cancer risk were included. Pooled odds ratio (OR) with 95% confidence interval (CI) was calculated using fixed- or random-effects model. Three studies (2,003 cases and 1,967 controls) for LEP G2548A polymorphism, nine studies (4,627 cases and 5,476 controls) for LEPR Q223R polymorphism, five studies (2,759 cases and 2,573 controls) for LEPR Lys109Arg polymorphism, four studies (1,517 cases and 1,379 controls) for PON1 L55M polymorphism, and five studies (1,575 cases and 2,283 controls) for PON1 Q192R polymorphism were included in the meta-analysis. Overall, the results showed null significant association between LEP G2548A, LEPR Q223R, LEPR Lys109Arg, or PON1 Q192R polymorphism and breast cancer risk; however, PON1 L55M was significantly associated with breast cancer risk overall (MM vs. LL: OR = 2.16; 95% CI, 1.76–2.66). For LEPR Q223R polymorphism, further subgroup analysis suggested that the association was only statistically significant in East Asians (OR = 0.50; 95% CI, 0.36–0.70) but not in Caucasians (OR = 1.06; 95% CI, 0.77–1.45) or Africans (OR = 1.30; 95% CI, 0.83–2.03). The present meta-analysis suggested that LEPR Q223R polymorphism might be implicated in the development of breast cancer in East Asians; PON1 L55M might increase breast cancer risk. However, given the limited sample size, the findings warrant further investigation.     

Effects of leptin and leptin receptor gene polymorphisms on lung cancer

Leptin (LEP), an adipocyte-derived cytokine, has been reported to participate in carcinogenesis. Elevated levels of systemic and pulmonary LEP are associated with diseases related to lung injury and lung cancer. The purpose of the present study was to investigate if the LEP and leptin receptor (LEPR) gene polymorphisms are associated with lung cancer in a cohort of Turkish population. One hundred and sixty-two lung cancer patients and 130 healthy controls were included in the study. The genotypes of LEP gene ?2548G?>?A and LEPR gene Q223R polymorphisms were determined using polymerase chain reaction (PCR) based restriction fragment length polymorphism (RFLP) analysis. The genotype frequencies of LEP ?2548G?>?A polymorphism showed statistically significant differences between lung cancer patients and controls (p?=?0.007). GA?+?AA genotypes and A allele of LEP ?2548G?>?A polymorphism was found to be susceptibility factors for lung cancer (p?=?0.003, odds ratio (OR) 2.32, 95 % confidence interval (CI) 1.32–4.10; p?=?0.003, OR 1.65, 95 % CI 1.18–2.29, respectively). The genotype and allele frequencies of LEPR Q223R polymorphism did not show any statistically significant differences between lung cancer patients and controls (p?=?0.782 and p?=?0.762, respectively). Although AA–QQ and AA–QR combined genotypes of LEP ?2548G?>?A-LEPR Q223R loci were significantly higher in lung cancer patients (p?=?0.020 and p?=?0.047, respectively), GG–QQ, GG–QR, and AA–RR combined genotypes were significantly higher in control group. As a result, susceptibility effects of LEP ?2548G?>?A polymorphism alone or in combination with LEPR Q223R polymorphism on lung cancer were observed. Further studies are necessary to prove the association of LEP and LEPR gene polymorphisms with lung cancer.     

Common genetic variations in the LEP and LEPR genes, obesity and breast cancer incidence and survival

Obesity is a strong risk factor for breast cancer in postmenopausal women and adverse prognostic indicator regardless of menopausal status. Leptin is an important regulator of adipose tissue mass and has been associated with tumor cell growth. Leptin exerts its effects through interaction with the leptin receptor (LEPR). We investigated whether genetic variations in the leptin (LEP) and LEPR genes are associated with risk of breast cancer, or once diagnosed, with survival. The polymorphisms LEP G-2548A and LEPR Q223R were characterized in population-based study consisting of mostly European-American women. The study examined 1,065 women diagnosed with first, primary invasive breast cancer between 1996 and 1997. Controls were 1,108 women frequency matched to the cases by 5-year age group. A modest increase in risk of developing breast cancer was associated with the LEP −2548AA genotype when compared to the LEP −2548GG genotype (age-adjusted OR = 1.30; 95% CI = 1.01–1.66). This association was stronger among postmenopausal women who were obese (OR = 1.86; 95% CI = 0.95–3.64) although the interaction was of borderline statistical significance (P = 0.07). We found no evidence of an association with polymorphisms of either LEP or LEPR in relation to all-cause or breast cancer-specific mortality among women with breast cancer (mean follow-up time = 66.7 months). The effects of these genotypes on breast cancer risk and mortality did not vary significantly when stratified by menopausal status. In summary, our results show that a common variant in LEP may be associated with the risk of developing breast cancer supporting the hypothesis that leptin is involved in breast carcinogenesis.     

Comprehensive pathway-based interrogation of genetic variations in the nucleotide excision DNA repair pathway and risk of bladder cancer

BACKGROUND:

Growing evidence suggests that single nucleotide polymorphisms (SNPs) in nucleotide excision repair (NER) pathway genes play an important role in bladder cancer etiology. However, only a limited number of genes and variations in this pathway have been evaluated to date.

METHODS:

In this study, the authors applied a comprehensive pathway‐based approach to assess the effects of 207 tagging and potentially functional SNPs in 26 NER genes on bladder cancer risk using a large case‐control study that included 803 bladder cancer cases and 803 controls.

RESULTS:

In total, 17 SNPs were associated significantly with altered bladder cancer risk (P < .05), of which, 7 SNPs retained noteworthiness after they were assessed with a Bayesian approach for the probability of false discovery. The most noteworthy SNP was reference SNP 11132186 (rs11132186) in the inhibitor of growth family, member 2 (ING2) gene. Compared with the major allele‐containing genotypes, the odds ratio was 0.52 (95% confidence interval, 0.32‐0.83; P = .005) for the homozygous variant genotype. Three additional ING2 variants also exhibited significant associations with bladder cancer risk. Significant gene‐smoking interactions were observed for 3 of the top 17 SNPs. Furthermore, through an exploratory classification and regression tree (CART) analysis, potential gene‐gene interactions were identified.

CONCLUSIONS:

In this a large association study of the NER pathway and the risk of bladder cancer, several novel predisposition variants were identified along with potential gene‐gene and gene‐environment interactions in modulating bladder cancer risk. The results reinforce the importance of a comprehensive, pathway‐focused, and tagging SNP‐based candidate gene approach to identify low‐penetrance cancer susceptibility loci. Cancer 2012;. © 2011 American Cancer Society.     

ADIPOQ polymorphism rs182052 is associated with clear cell renal cell carcinoma

Recent studies have indicated that low circulating adiponectin concentrations are associated with a higher risk of several cancers, including renal cell carcinoma. In this case–control study, we examined the frequency of single nucleotide polymorphisms (rs182052G>A, rs266729C>G, and rs3774262G>A) in the adiponectin gene (ADIPOQ) in 1004 patients with clear cell renal cell carcinoma (ccRCC) compared with a group of healthy subjects (n = 1108). Fasting serum adiponectin concentrations were also examined. Logistic regression models were used to estimate odds ratios (OR) and 95% confidence intervals (95% CI). The association of serum adiponectin concentration with genetic variants was calculated using a multivariate linear regression model. A significantly higher ccRCC risk was associated with the rs182052 variant A allele (adjusted OR, 1.36 and 95% CI, 1.07–1.74 for AA vs GG, P = 0.013; adjusted OR, 1.27 and 95% CI, 1.04–1.56 for AA vs GG+AG, P = 0.019), and this positive association was more evident in overweight subjects. Fasting serum adiponectin was lower in subjects carrying A alleles of rs182052 in both ccRCC patients (β = −0.399, P = 0.018) and healthy controls (β = −0.371, P = 0.024). These results suggest that ADIPOQ rs182052 is significantly associated with ccRCC risk.In this case–control study, we examined the frequency of single nucleotide polymorphisms (rs182052G>A, rs266729C>G, and rs3774262G>A) in the adiponectin gene (ADIPOQ) in 1004 patients with clear cell RCC (ccRCC) compared with a group of healthy subjects (n = 1108). Fasting serum adiponectin concentrations were also examined. Fasting serum adiponectin was lower in subjects carrying minor alleles of rs182052 in both ccRCC patients (β = −0.399, P = 0.018) and healthy controls (β = −0.371, P = 0.024). These results suggest that ADIPOQ rs182052 is significantly associated with ccRCC risk.     

Leptin and leptin receptor polymorphisms are associated with increased risk and poor prognosis of breast carcinoma

Background  

Leptin (LEP) has been consistently associated with angiogenesis and tumor growth. Leptin exerts its physiological action through its specific receptor (LEPR). We have investigated whether genetic variations in LEP and LEPR have implications for susceptibility to and prognosis in breast carcinoma.     

A single nucleotide polymorphism in ADIPOQ predicts biochemical recurrence after radical prostatectomy in localized prostate cancer

Adiponectin has been implicated in prostate cancer (PCa) aggressiveness. However, the role of genetic variations in the adiponectin (ADIPOQ) gene in PCa progression remains unknown. To determine whether genetic variants in ADIPOQ are associated with the risk of biochemical recurrence (BCR) after radical prostatectomy (RP). We evaluated three common ADIPOQ polymorphisms in 728 men with clinically localized PCa who underwent RP. Multivariable Cox proportional hazards models and Kaplan–Meier analysis were used to assess their prognostic significance on BCR. The plasma adiponectin concentrations were measured by enzyme-linked immunosorbent assay. ADIPOQ rs182052 variant allele was associated with both increased risk of BCR [HR: 2.44; 95% confidence interval (CI): 1.57–3.79, P = 6×10⁻⁵] and decreased adiponectin level (β = −0.048, P = 0.004). Stratified analyses demonstrated that the association was more pronounced in men with higher visceral adipose tissue. Our data support that the ADIPOQ rs182052 SNP may be a predictive biomarker for BCR after RP by a possible mechanism of altering the adiponectin level. If validated, genetic predictors of outcome may help individualizing treatment for PCa.     

Single nucleotide polymorphisms associated with risk for contralateral breast cancer in the Women's Environment, Cancer, and Radiation Epidemiology (WECARE) Study

Introduction

Genome-wide association studies, focusing primarily on unilateral breast cancer, have identified single nucleotide polymorphisms (SNPs) in a number of genomic regions that have alleles associated with a significantly increased risk of breast cancer. In the current study we evaluate the contributions of these previously identified regions to the risk of developing contralateral breast cancer. The most strongly disease-associated SNPs from prior studies were tested for association with contralateral breast cancer. A subset of these SNPs, selected upon their main effects on contralateral breast cancer risk was further evaluated for interaction with treatment modalities and estrogen receptor (ER) status.

Methods

We genotyped 21 SNPs in 708 women with contralateral breast cancer and 1394 women with unilateral breast cancer who serve as the cases and controls in the Women's Environment, Cancer and Radiation Epidemiology (WECARE) Study. Records of treatment and ER status were available for most of WECARE Study participants. Associations of SNP genotypes and risk for contralateral breast cancer were calculated with multivariable adjusted conditional logistic regression methods.

Results

Multiple SNPs in the FGFR2 locus were significantly associated with contralateral breast cancer, including rs1219648 (per allele rate ratio (RR) = 1.25, 95%CI = 1.08-1.45). Statistically significant associations with contralateral breast cancer were also observed at rs7313833, near the PTHLH gene (per allele RR = 1.26, 95%CI = 1.08-1.47), rs13387042 (2q35) (per allele RR = 1.19, 95%CI = 1.02-1.37), rs13281615 (8q24) (per allele RR = 1.21, 95%CI = 1.04-1.40), and rs11235127 near TMEM135 (per allele RR = 1.26, 95%CI = 1.04-1.53). The A allele of rs13387042 (2q35) was significantly associated with contralateral breast cancer in ER negative first tumors while the A allele of rs11235127 (near TMEM135) was significantly associated with contralateral breast cancer in ER positive first tumors. Although some SNP genotypes appeared to modify contralateral breast cancer risk with respect to tamoxifen treatment or particular radiation doses, trend tests for such effects were not significant.

Conclusions

Our results indicate that some common risk variants associated with primary breast cancer also increase risk for contralateral breast cancer, and that these risks vary with the ER status of the first tumor.     

Clinical and genetic predictors of weight gain in patients diagnosed with breast cancer

Background:

Post-diagnosis weight gain in breast cancer patients has been associated with increased cancer recurrence and mortality. Our study was designed to identify risk factors for this weight gain and create a predictive model to identify a high-risk population for targeted interventions.

Methods:

Chart review was conducted on 459 breast cancer patients from Northwestern Robert H. Lurie Cancer Centre to obtain weights and body mass indices (BMIs) over an 18-month period from diagnosis. We also recorded tumour characteristics, demographics, clinical factors, and treatment regimens. Blood samples were genotyped for 14 single-nucleotide polymorphisms (SNPs) in fat mass and obesity-associated protein (FTO) and adiponectin pathway genes (ADIPOQ and ADIPOR1).

Results:

In all, 56% of patients had >0.5 kg m^–2 increase in BMI from diagnosis to 18 months, with average BMI and weight gain of 1.9 kg m^–2 and 5.1 kg, respectively. Our best predictive model was a primarily SNP-based model incorporating all 14 FTO and adiponectin pathway SNPs studied, their epistatic interactions, and age and BMI at diagnosis, with area under receiver operating characteristic curve of 0.85 for 18-month weight gain.

Conclusion:

We created a powerful risk prediction model that can identify breast cancer patients at high risk for weight gain.     

SNP-SNP interactions between DNA repair genes were associated with breast cancer risk in a Korean population

BACKGROUND:

Single nucleotide polymorphisms (SNPs) in nucleotide excision repair (NER) pathway genes may modulate DNA repair capacity and increase susceptibility to breast cancer (BC). A case‐control study was conducted by evaluating genes involved in DNA repair to identify polymorphisms associated with BC.

METHODS:

The 384 SNPs of 38 candidate genes were genotyped using the Illumina GoldenGate method. Genotypes were determined in a case‐control study that consisted of 346 BC patients and 361 controls. Odds ratios and 95% confidence intervals were computed using logistic regression models. Multiple logistic regression models adjusted for age, family history of BC, and body mass index were used.

RESULTS:

Gene–gene interaction analysis among the DNA repair pathway genes showed significant effects on BC risk. ERCC2 rs50872 (TC genotype) in combination with XPA rs2808668 (TC genotype) and rs1800975 (AG genotype) was strongly associated with an increased risk of BC (P = .0004 and .0002, P_Bonferroni = .023 and .014, respectively). Moreover, the T‐G (including rs2808668 and rs1800975) haplotype in XPA combined with the ERCC2 T allele in rs50872 carriers was also associated with additive risk effect of BC (odds ratios: 2.58, 2.62, and 3.49, respectively).

CONCLUSION:

Genetic variation in DNA repair genes involved in NER mechanisms increased the risk of BC development. These results suggested that a stronger combined effect of SNPs via gene–gene interaction may help to predict BC risk. Cancer 2012;. © 2011 American Cancer Society.