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Background: Previous prospective studies have found an association between prolactin (PRL) levels and increased risk of breast cancer. Using data from a population-based breast cancer case-control study conducted in two cities in Poland (2000-2003), we examined the association of PRL levels with breast cancer risk factors among controls and with tumour characteristics among the cases.Methods: We analysed PRL serum levels among 773 controls without breast cancer matched on age and residence to 776 invasive breast cancer cases with available pretreatment serum. Tumours were centrally reviewed and prepared as tissue microarrays for immunohistochemical analysis. Breast cancer risk factors, assessed by interview, were related to serum PRL levels among controls using analysis of variance. Mean serum PRL levels by tumour characteristics are reported. These associations also were evaluated using polytomous logistic regression.Results: Prolactin levels were associated with nulliparity in premenopausal (P=0.05) but not in postmenopausal women. Associations in postmenopausal women included an inverse association with increasing body mass index (P=0.0008) and direct association with use of recent/current hormone therapy (P=0.0006). In case-only analyses, higher PRL levels were more strongly associated with lobular compared with ductal carcinoma among postmenopausal women (P=0.02). Levels were not different by tumour size, grade, node involvement or oestrogen receptor, progesterone receptor, or human epidermal growth factor receptor 2 status.Conclusions: Our analysis demonstrates that PRL levels are higher among premenopausal nulliparous as compared with parous women. Among postmenopausal women, levels were higher among hormone users and lower among obese women. These results may have value in understanding the mechanisms underlying several breast cancer risk factor associations. [ABSTRACT FROM AUTHOR]

Telomeres, consisting of TTAGGG nucleotide repeats and a protein complex at chromosome ends, are critical for maintaining chromosomal stability. Genomic instability, following telomere crisis, may contribute to breast cancer pathogenesis. Many genes critical in telomere biology have limited nucleotide diversity, thus, single nucleotide polymorphisms (SNPs) in this pathway could contribute to breast cancer risk. In a population-based study of 1995 breast cancer cases and 2296 controls from Poland, 24 SNPs representing common variation in POT1, TEP1, TERF1, TERF2 and TERT were genotyped. We did not identify any significant associations between individual SNPs or haplotypes and breast cancer risk; however, data suggested that three correlated SNPs in TERT (-1381C>T, -244C>T, and Ex2-659G>A) may be associated with reduced risk of breast cancer among individuals with a family history of breast cancer (odds ratios 0.73, 0.66, and 0.57, 95% confidence intervals 0.53-1.00, 0.46-0.95 and 0.39-0.84, respectively). In conclusion, our data do not support substantial overall associations between SNPs in telomere pathway genes and breast cancer risk. Intriguing associations with variants in TERT among women with a family history of breast cancer warrant follow-up in independent studies. [ABSTRACT FROM AUTHOR]

We conducted a population-based case-control study of reproductive factors in Warsaw and Lódź, Poland, in 551 incident endometrial cancer cases and 1925 controls. The reproductive variable most strongly related to risk was multiparity, with subjects with three or more births having a 70% lower risk than the nulliparous women. The reduced risk was particularly strong below 55 years of age. Subjects with older ages at a first birth were also at reduced risk even after adjustment for number of births. Ages at last birth or intervals since last birth were not strongly related to risk. Spontaneous abortions were unrelated to risk, but induced abortions were associated with slight risk increases (odds ratios=1.28, 95% confidence intervals 0.8-2.1 for 3+ vs no abortions). The absence of effects on risk of later ages at, or short intervals since, a last birth fails to support the view that endometrial cancer is influenced by mechanical clearance of initiated cells. Alternative explanations for reproductive effects should be sought, including alterations in endogenous hormones. [ABSTRACT FROM AUTHOR]

The article presents information about a study conducted to discover the health effect of combustion generated pollutants, principally those from solid fuel fired cooking and heating stoves. Data were collected by interviewing 800 cytologically/histologically confirmed patients with lung cancer in the two largest cities of Poland, Warsaw and Lodz. It was found that odds ratio for lung cancer associated with solid fuel use in the house was 1.54. Risk increased to 5.11 for those who had only used solid fuels compared with those who had never used solid fuels at their homes. The risk of lung cancer increased relative to the percentage time that solid fuel was used at home.

Background: Although early diagnosis and surgical resection of the tumor have been shown to be the most important predictors of lung cancer survival, long-term survival for surgically-resected early-stage lung cancer remains poor., Aims: In this prospective study we aimed to investigate the survival and prognostic factors of surgically-resected early-stage non-small cell lung cancer (NSCLC) in Central and Eastern Europe., Methods: We recruited 2052 patients with stage I-IIIA NSCLC from 9 centers in Russia, Poland, Serbia, Czech Republic, and Romania, between 2007-2016 and followed them annually through 2020., Results: During follow-up, there were 1121 deaths (including 730 cancer-specific deaths). Median survival time was 4.9 years, and the 5-year overall survival was 49.5%. In the multivariable model, mortality was increased among older individuals (HR for each 10-year increase: 1.31 [95% CI: 1.21-1.42]), males (HR:1.24 [1.04-1.49]), participants with significant weight loss (HR:1.25 [1.03-1.52]), current smokers (HR:1.30 [1.04-1.62]), alcohol drinkers (HR:1.22 [1.03-1.44]), and those with higher stage tumors (HR stage IIIA vs. I: 5.54 [4.10 - 7.48]). However, education, chronic obstructive pulmonary diseases (COPD), and tumor histology were not associated with risk of death. All baseline indicators of smoking and alcohol drinking showed a dose-dependent association with the risk of cancer-specific mortality. This included pack-years of cigarettes smoked (p-trend = 0.04), quantity of smoking (p-trend = 0.008), years of smoking (p-trend = 0.010), gram-days of alcohol drank (p-trend = 0.002), frequency of drinking (p-trend = 0.006), and years of drinking (p-trend = 0.016)., Conclusion: This study shows that the 5-year survival rate of surgically-resected stage I-IIIA NSCLC is still around 50% in Central and Eastern Europe. In addition to non-modifiable prognostic factors, lifetime patterns of smoking and alcohol drinking affected the risk of death and disease progression in a dose-dependent manner in this population., (© 2023 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.)

Purpose: Tumor-associated stroma is comprised of fibroblasts, tumor-infiltrating lymphocytes (TIL), macrophages, endothelial cells, and other cells that interactively influence tumor progression through inflammation and wound repair. Although gene-expression signatures reflecting wound repair predict breast cancer survival, it is unclear whether combined density of tumor-associated stromal cells, a morphologic proxy for inflammation and wound repair signatures on routine hematoxylin and eosin (H&E)-stained sections, is of prognostic relevance., Methods: By applying machine learning to digitized H&E-stained sections for 2,084 breast cancer patients from China ( n = 596; 24-55 years), Poland ( n = 810; 31-75 years), and the United States ( n = 678; 55-78 years), we characterized tumor-associated stromal cellular density (SCD) as the percentage of tumor-stroma that is occupied by nucleated cells. Hazard ratios (HR) and 95% confidence intervals (CI) for associations between SCD and clinical outcomes [recurrence (China) and mortality (Poland and the United States)] were estimated using Cox proportional hazard regression, adjusted for clinical variables., Results: SCD was independently predictive of poor clinical outcomes in hormone receptor-positive (luminal) tumors from China [multivariable HR (95% CI) fourth(Q4) vs. first(Q1) quartile = 1.86 (1.06-3.26); P = 0.03], Poland [HR (95% CI) trend = 0.03], Poland [HR (95% CI) Q4 vs. Q1 = 1.80 (1.12-2.89); P trend = 0.01], and the United States [HR (95% CI) Q4 vs. Q1 = 2.42 (1.33-4.42); P trend = 0.002]. In general, SCD provided more prognostic information than most classic clinicopathologic factors, including grade, size, PR, HER2, IHC4, and TILs, predicting clinical outcomes irrespective of menopausal or lymph nodal status. SCD was not predictive of outcomes in hormone receptor-negative tumors., Conclusions: Our findings support the independent prognostic value of tumor-associated SCD among ethnically diverse luminal breast cancer patients., Impact: Assessment of tumor-associated SCD on standard H&E could help refine prognostic assessment and therapeutic decision making in luminal breast cancer., (©2021 American Association for Cancer Research.)

Background: Pelvic inflammatory disease (PID) has been associated with ovarian cancer risk. To clarify the role of Chlamydia trachomatis and other infectious agents in the development of ovarian cancer, we evaluated the association of serologic markers with incident ovarian cancer using a staged approach in two independent populations., Methods: Studies included: 1) a case-control study in Poland (244 ovarian cancers/556 control subjects) and 2) a prospective nested case-control study in the PLCO Cancer Screening Trial (160 ovarian cancers/159 control subjects). Associations of serologic marker levels with ovarian cancer risk at diagnostic as well as higher thresholds, identified in Poland and independently evaluated in PLCO, were estimated using multivariable adjusted logistic regression., Results: In the Polish study, antibodies (based on laboratory cut-point) against the chlamydia plasmid-encoded Pgp3 protein (serological gold standard) were associated with increased ovarian cancer risk (adjusted odds ratio [OR] = 1.63, 95% confidence interval [CI] = 1.20 to 2.22); when a positive result was redefined at higher levels, ovarian cancer risk was increased (cut-point 2: OR = 2.00, 95% CI = 1.38 to 2.89; cut-point 3 [max OR]: OR = 2.19, 95% CI = 1.29 to 3.73). In the prospective PLCO study, Pgp3 antibodies were associated with elevated risk at the laboratory cut-point (OR = 1.43, 95% CI = 0.78 to 2.63) and more stringent cut-points (cut-point 2: OR = 2.25, 95% CI = 1.07 to 4.71); cut-point 3: OR = 2.53, 95% CI = 0.63 to 10.08). In both studies, antibodies against other infectious agents measured were not associated with risk., Conclusions: In two independent populations, antibodies against prior/current C. trachomatis (Pgp3) were associated with a doubling in ovarian cancer risk, whereas markers of other infectious agents were unrelated. These findings lend support for an association between PID and ovarian cancer., (Published by Oxford University Press 2018.)

Background: Basal-like breast cancer (BLBC) is a rare aggressive subtype that is less likely to be detected through mammographic screening. Identification of circulating markers associated with BLBC could have promise in detecting and managing this deadly disease., Methods: Using samples from the Polish Breast Cancer study, a high-quality population-based case-control study of breast cancer, we screened 10,000 antigens on protein arrays using 45 BLBC patients and 45 controls, and identified 748 promising plasma autoantibodies (AAbs) associated with BLBC. ELISA assays of promising markers were performed on a total of 145 BLBC cases and 145 age-matched controls. Sensitivities at 98% specificity were calculated and a BLBC classifier was constructed., Results: We identified 13 AAbs (CTAG1B, CTAG2, TP53, RNF216, PPHLN1, PIP4K2C, ZBTB16, TAS2R8, WBP2NL, DOK2, PSRC1, MN1, TRIM21) that distinguished BLBC from controls with 33% sensitivity and 98% specificity. We also discovered a strong association of TP53 AAb with its protein expression (P = 0.009) in BLBC patients. In addition, MN1 and TP53 AAbs were associated with worse survival [MN1 AAb marker HR = 2.25, 95% confidence interval (CI), 1.03-4.91; P = 0.04; TP53, HR = 2.02, 95% CI, 1.06-3.85; P = 0.03]. We found limited evidence that AAb levels differed by demographic characteristics., Conclusions: These AAbs warrant further investigation in clinical studies to determine their value for further understanding the biology of BLBC and possible detection., Impact: Our study identifies 13 AAb markers associated specifically with BLBC and may improve detection or management of this deadly disease., (©2015 American Association for Cancer Research.)

DNA methylation is a potential mechanism linking indoor air pollution to adverse health effects. Fetal and early-life environmental exposures have been associated with altered DNA methylation and play a critical role in progress of diseases in adulthood. We investigated whether exposure to indoor air pollution from solid fuels at different lifetime periods was associated with global DNA methylation and methylation at the IFG2/H19 imprinting control region (ICR) in a population-based sample of non-smoking women from Warsaw, Poland. Global methylation and IFG2/H19 ICR methylation were assessed in peripheral blood DNA from 42 non-smoking women with Luminometric Methylation Assay (LUMA) and quantitative pyrosequencing, respectively. Linear regression models were applied to estimate associations between indoor air pollution and DNA methylation in the blood. Compared to women without exposure, the levels of LUMA methylation for women who had ever exposed to both coal and wood were reduced 6.70% (95% CI: -13.36, -0.04). Using both coal and wood before age 20 was associated with 6.95% decreased LUMA methylation (95% CI: -13.79, -0.11). Further, the negative correlations were more significant with exposure to solid fuels for cooking before age 20. There were no clear associations between indoor solid fuels exposure before age 20 and through the lifetime and IFG2/H19 ICR methylation. Our study of non-smoking women supports the hypothesis that exposure to indoor air pollution from solid fuels, even early-life exposure, has the capacity to modify DNA methylation that can be detected in peripheral blood., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Previous studies have found an association between elevated circulating prolactin levels and increased risk of breast cancer. Prolactin stimulates breast cancer cell proliferation, migration, and survival via binding to the cell-surface prolactin receptor. The association of prolactin receptor expression with breast tumorigenesis remains unclear as studies that have focused on this association have had limited sample size and/or information about tumor characteristics. Here, we examined the association of prolactin expression with tumor characteristics among 736 cases, from a large population-based case-control study of breast cancer conducted in Poland (2000-2003), with detailed risk factor and pathology data. Tumors were centrally reviewed and prepared as tissue microarrays for immunohistochemical analysis of prolactin receptor expression. Association of prolactin receptor expression across strata of tumor characteristics was evaluated using χ (2) analysis and logistic regression. Prolactin receptor expression did not vary by menopausal status; therefore, data from pre- and post-menopausal women were combined in the analyses. Approximately 83 % of breast cancers were categorized as strong prolactin receptor staining. Negative/low prolactin receptor expression was independently associated with poorly differentiated (p = 1.2 × 10(-08)) and larger tumors (p = 0.0005). These associations were independent of estrogen receptor expression. This is the largest study to date in which the association of prolactin receptor expression with tumor characteristics has been evaluated. These data provide new avenues from which to explore the associations of the prolactin/prolactin receptor signaling network with breast tumorigenesis.

Recently, two large genome-wide association studies, conducted in Chinese populations, have reported associations between upper gastrointestinal cancer and the rs2274223, rs13042395 and rs4072037 polymorphisms in PLCE1, C20orf54 and MUC1, respectively. We aimed to determine whether similar associations existed for Caucasian populations. We genotyped two population-based, case-control studies of upper gastrointestinal cancer; the first study included 290 gastric cancer (GC) cases and 376 controls and the second study included 306 GC cases, 107 oesophageal adenocarcinoma cancer cases, 52 oesphageal squamous cell cancer cases and 211 controls. Odds ratios (OR) and 95% confidence intervals (CIs) were computed from logistic models and adjusted for confounding variables. The rs4072037 polymorphism in MUC1 was associated with a reduced risk of GC of intestinal histological type (OR 0.4; 95% CI 0.2-0.9) and a reduced risk of oesophageal squamous cell cancer (OR 0.5; 95% CI 0.2-1.0), but not oesphageal adenocarcinoma. Similarly, rs2274223 in PLCE1 was associated with a reduced risk of oesophageal squamous cell cancer (OR 0.5; 95% CI 0.3-1.0), but not oesphageal adenocarcinoma. We observed no association between rs13042395 in Corf54 and the risk of gastric or oesphageal cancer in either of the two studies. Our findings for rs4072037 and the risk of GC are in agreement with one previous report for a Caucasian population. To the best of our knowledge, this is the first study to report an association between rs2274223 and rs4072037 and the risk of oesophageal squamous cell carcinoma in a Caucasian population.

Context: Endometrial cancer is associated with metabolic disturbances related to its underlying risk factors, including obesity and diabetes. Identifying metabolite biomarkers associated with endometrial cancer may have value for early detection, risk assessment, and understanding etiology., Objective: The objective of the study was to evaluate the reliable measurement of metabolites in epidemiological studies with nonstandardized blood collection; confirm previously reported correlations of metabolites with body size; and assess differences in metabolite levels between cases and controls., Design: This was the Polish Endometrial Cancer Study (2001-2003)., Setting: This study was a population-based case-control study., Patients: Patients included 250 cases and 250 controls., Intervention: The intervention included the measurement of serum metabolite levels of 15 amino acids, 45 acylcarnitines, and nine fatty acids., Main Outcome Measure: The main outcome measure was endometrial cancer., Results: Body mass index was correlated with levels of valine (r = 0.26, P = 3.4 × 10(-5)), octenoylcarnitine (r = 0.24, P = 1.5 × 10(-4)), palmitic acid (r = 0.26, P = 4.4 × 10(-5)), oleic acid (r = 0.28, P = 9.9 × 10(-6)), and stearic acid (r = 0.26, P = 2.9 × 10(-5)) among controls. Only stearic acid was inversely associated with endometrial cancer case status (quartile 4 vs. quartile 1: odds ratio 0.37, 95% confidence interval 0.20-0.69, P for trend = 1.2 × 10(-4)). Levels of the C5-acylcarnitines, octenoylcarnitine, decatrienoylcarnitine, and linoleic acid were significantly lower in cases than controls (odds ratios ranged from 0.21 to 0.38)., Conclusions: These data demonstrate that previously reported variations in metabolomic profiles with body mass index can be replicated in population-based studies with nonfasting blood collection protocols. We also provide preliminary evidence that large differences in metabolite levels exist between cases and controls, independent of body habitus. Our findings warrant assessment of metabolic profiles, including the candidate markers identified herein, in prospectively collected blood samples to define biomarkers and etiological factors related to endometrial cancer.

Childbearing at an older age has been associated with a lower risk of endometrial cancer, but whether the association is independent of the number of births or other factors remains unclear. Individual-level data from 4 cohort and 13 case-control studies in the Epidemiology of Endometrial Cancer Consortium were pooled. A total of 8,671 cases of endometrial cancer and 16,562 controls were included in the analysis. After adjustment for known risk factors, endometrial cancer risk declined with increasing age at last birth (P(trend) < 0.0001). The pooled odds ratio per 5-year increase in age at last birth was 0.87 (95% confidence interval: 0.85, 0.90). Women who last gave birth at 40 years of age or older had a 44% decreased risk compared with women who had their last birth under the age of 25 years (95% confidence interval: 47, 66). The protective association was similar across the different age-at-diagnosis groups and for the 2 major tumor histologic subtypes (type I and type II). No effect modification was observed by body mass index, parity, or exogenous hormone use. In this large pooled analysis, late age at last birth was independently associated with a reduced risk of endometrial cancer, and the reduced risk persisted for many years.

Intake of acetaldehyde in alcoholic beverages, in central Europe, might explain the high rate of alcohol-related diseases in these countries. We measured the acetaldehyde level in 30 samples of home-made spirits and 12 samples of industry-made spirits from four central European countries, including 35 fruit-based and five grain-based spirits. Acetaldehyde was detected in all fruit-based spirits and in none of the grain-based spirits. Acetaldehyde levels were above 2000 µmol/l in 12 samples, 11 of which were home-made. In a multivariate analysis restricted to fruit-based spirits, however, the difference between home-made and industry-based spirits was not statistically significant. These results add evidence to the hypothesis that intake of acetaldehyde in alcoholic beverages, in central Europe, contributes to the burden of alcohol-related disease, especially that of upper digestive tract cancers. The acetaldehyde level should be monitored and high-level exposure should be avoided.

Introduction: Studies suggest that high circulating levels of prolactin increase breast cancer risk. It is unclear if genetic variations in prolactin (PRL) or prolactin receptor (PRLR) genes also play a role. Thus, we examined the relationship between single nucleotide polymorphisms (SNPs) in PRL and PRLR, serum prolactin levels and breast cancer risk in a population-based case-control study., Methods: We genotyped 8 PRL and 20 PRLR tag SNPs in 1965 breast cancer cases and 2229 matched controls, aged 20-74, and living in Warsaw or Łódź, Poland. Serum prolactin levels were measured by immunoassay in a subset of 773 controls. Odds ratios (ORs) and 95% confidence intervals (CIs) for genotype associations with breast cancer risk were estimated using unconditional logistic regression, adjusted for age and study site. Geometric mean prolactin levels were estimated using linear regression models adjusted for age, study site, blood collection time, and menstrual cycle day (premenopausal women)., Results: Three SNPs were associated with breast cancer risk: in premenopausal women, PRLR rs249537 (T vs. C per-allele OR 1.39, 95% CI 1.07 - 1.80, P = 0.01); and in postmenopausal women, PRLR rs7718468 (C vs. T per-allele OR 1.16, 95% CI 1.03 - 1.30, P = 0.01) and PRLR rs13436213 (A vs. G per-allele OR 1.13 95% CI 1.01 - 1.26, P = 0.04). However, mean serum prolactin levels for these SNPs did not vary by genotype (P-trend > 0.05). Other SNPs were associated with serum prolactin levels: PRLR rs62355518 (P-trend = 0.01), PRLR rs10941235 (P-trend = 0.01), PRLR rs1610218 (P-trend = 0.01), PRLR rs34024951 (P-trend = 0.02), and PRLR rs9292575 (P-trend = 0.03) in premenopausal controls and PRL rs849872 (P-trend = 0.01) in postmenopausal controls., Conclusions: Our data provide limited support for an association between common variations in PRLR and breast cancer risk. Altered serum prolactin levels were not associated with breast cancer risk-associated variants, suggesting that common genetic variation is not a strong predictor of prolactin-associated breast cancer risk in this population.

Over recent years, genome-wide association studies have contributed to our understanding of genetic susceptibility to sporadic cancer. In this study, we assessed the association between upper gastrointestinal cancer risk and four genome-wide association studies-identified single nucleotide polymorphisms (SNPs), implicated earlier in prostate and colorectal cancer susceptibility. Genotyping for each SNP was performed in two independent Caucasian population-based case-control studies. The first study comprised 290 gastric cancer cases and 374 controls. The second study included 185 noncardia gastric cancers, 123 cardia cancers, 158 oesophageal cancers and 209 controls. Odds ratios (ORs) were computed from logistic models and adjusted for potential confounding variables. An inverse association was observed between the SNP rs1447295, located at 8q24, and gastric cancer risk in the first study population (OR=0.63; 95% confidence interval: 0.41-0.97). A positive association was observed for the same SNP and oesophageal squamous cell carcinoma in the second study population (OR=7.43; 95% confidence interval: 1.37-49.98). No significant associations were detected in either study for the three remaining SNPs (rs6983297, rs10505477 and rs719725). Our data represent novel findings on heritable susceptibility to gastric and oesophageal cancer and warrant validation in additional populations.

Background: Although studies in rodents suggest possible associations between exposure to organic solvents and breast cancer, the evidence in humans is limited., Methods: We evaluated job histories of 2383 incident breast cancer cases diagnosed during 2000-2003, and 2502 controls who participated in a large population-based case-control study in Poland. Industrial hygienists reviewed occupational histories and developed exposure metrics for total organic solvents and benzene. Unconditional logistic regression analyses estimated ORs and 95% CIs as the measure of association with breast cancer, controlling for breast cancer risk factors. Stratified analyses examined the potential modification by known breast cancer risk factors. Associations were also evaluated by oestrogen and progesterone receptor status and by other clinical characteristics of the tumours using polytomous regression analyses., Results: Women who ever worked at jobs with organic solvents exposure had a small, non-significant increase in breast cancer risk (OR=1.16; 95% CI 0.99 to 1.4). A significant association was present for oestrogen receptor- and progesterone receptor-negative tumours (OR 1.40; 95% CI 1.1 to 1.8), but there was no association with tumours with both positive receptors (OR 0.97; 95% CI 0.8 to 1.2 (p heterogeneity: 0.008)). We did not observe trends with increasing level of exposure. Known breast cancer risk factors did not modify the association between organic solvents and breast cancer risk. No association with breast cancer was found for benzene exposure (OR 1.00; 95% CI 0.8 to 1.3)., Conclusion: Our study provides weak evidence for a possible association between occupational exposure to organic solvents as a class and breast cancer risk. The association might be limited to hormone receptor-negative tumours.

Global hypomethylation has been shown to increase genome instability potentially leading to increased cancer risk. We determined whether global methylation in blood leukocyte DNA was associated with gastric cancer in a population-based study on 302 gastric cancer cases and 421 age- and sex-matched controls in Warsaw, Poland, between 1994 and 1996. Using PCR-pyrosequencing, we analyzed methylation levels of Alu and LINE-1, 2 CG-rich repetitive elements, to measure global methylation levels. Gastric cancer risk was highest among those with lowest level of methylation in either Alu (OR = 1.3, 95% CI = 0.9-1.9) or LINE-1 (OR = 1.4, 95% CI = 0.9-2.0) relative to those with the highest levels, although the trends were not statistically significant. For Alu, the association was stronger among those aged 70 or older (OR = 2.6, 95% CI = 1.3-5.5, p for interaction = 0.02). We did not observe meaningful differences in the associations by other risk factors and polymorphisms examined. For LINE-1, the association tended to be stronger among individuals with a family history of cancer (OR = 3.1, 95% CI = 1.4-7.0, p for interaction = 0.01), current alcohol drinkers (OR = 1.9, 95% CI = 1.0-3.6, p for interaction = 0.05), current smokers (OR = 2.3, 95% CI = 1.1-4.6, p for interaction = 0.02), those who rarely or never consumed fruit (OR = 3.1, 95% CI = 1.2-8.1, p for interaction = 0.03), CC carriers for the MTRR Ex5+123C>T polymorphism (OR = 2.3, 95% CI = 1.2-4.4, p for interaction = 0.01) and TT carriers for the MTRR Ex15+572T>C polymorphism (OR = 1.7, 95% CI = 1.0-2.8, p for interaction = 0.06). The association was not different by sex, Helicobacter pylori infection, intake of folate, vitamin B6 and total protein and the remaining polymorphisms examined. Our results indicate that interactions between blood leukocyte DNA hypomethylation and host characteristics may determine gastric cancer risk.

The transforming growth factor beta (TGF-beta) pathway can play either a tumor-suppressing or a tumor-promoting role in human breast carcinogenesis. In order to determine whether expression of TGF-beta signaling factors varies by age at onset and breast tumor characteristics that have prognostic significance, we undertook a study of 623 women with invasive breast carcinoma enrolled in a population-based case-control study conducted in Poland from 2000 to 2003. TGF-beta signaling factors were analyzed by immunohistochemistry in tumor tissue microarrays. We found that most tumors expressed extracellular-TGF-beta1 (78%), TGF-beta2 (91%), TGF-beta3 (93%), TGF-betaR2 (72%), and phospho-SMAD2 (61%), whereas intracellular-TGF-beta1 was expressed in 32% of tumors. Expression of TGF-beta ligands (beta1, beta2, and beta3) was associated with prognostically favorable pathological features including small size, and low grade, and these associations were similar for ER-positive and negative tumors. On the contrary, expression of the receptor TGF-betaR2 was primarily associated with small tumor size among ER-negative tumors, while expression of the transcription factor phospho-SMAD2 was associated with positive nodal status among ER-negative tumors. The greater frequency of expression of phospho-SMAD2 in cancers associated with lymph node metastases is consistent with a pro-progression role for TGF-beta. In addition, expression of extracellular-TGF-beta1 (P = 0.005), TGF-betaR2 (P = 8.2E-11), and phospho-SMAD2 (P = 1.3E-8) was strongly associated with earlier age at onset, independent of ER status. Our data provide evidence that TGF-beta signaling patterns vary by age and pathologic features of prognostic significance including ER expression. These results warrant analysis in studies of clinical outcomes accounting for age, ER status and treatment.

Background: Epidemiological studies have consistently reported that active cigarette smoking is inversely associated with endometrial cancer risk. However, dose-response relationships with quantitative measures of active smoking or passive smoking remain less clear., Methods: Data on lifetime active and passive smoking were collected for 551 endometrial cancer cases and 1925 controls in a population-based case-control study conducted during 2001-2003 in Poland (Warsaw and Łódz)., Results: Compared with never active smokers, active current (Odds Ratio (OR)=0.51, 95% Confidence Interval (CI): 0.39, 0.68) and former smokers (OR=0.60, 95% CI: 0.45, 0.80) were at a statistically significantly decreased risk. We did not observe statistically significant inverse dose-response relationships with increasing exposure with duration and cumulative measures. However, there was some indication that the highest category of number of years (OR=0.35, 95% CI: 0.23-0.55), intensity (OR=0.41, 95% CI: 0.24-0.69), and dose (OR=0.38, 95% CI: 0.24-0.60) of smoking among current smokers had the greatest inverse association compared to never smokers. Our data did not support the presence of an inverse association with passive smoking among never active smokers (OR=0.92; 95% CI: 0.65, 1.29)., Conclusion: Our results support that long-term and heavy smoking among current smokers strongly influence endometrial cancer risk., (Published by Elsevier Ltd.)

Telomere length reflects lifetime cumulative oxidative stress from environmental exposures, such as cigarette smoking and chronic inflammation. Shortened telomere length is thought to cause genomic instability and has been associated with several cancers. We examined the association of telomere length in peripheral leukocyte DNA with gastric cancer risk as well as potential confounding factors and risk modifiers for telomere length-related risk. In a population-based study of gastric cancer conducted in a high-risk population in Warsaw, Poland, between 1994 and 1996, we measured relative telomere length in 300 cases and 416 age- and gender-matched controls using quantitative real-time PCR. Among controls, telomeres were significantly shorter in association with aging (P < 0.001), increasing pack-years of cigarette smoking (P = 0.02), decreasing fruit intake (P = 0.04), and Helicobacter pylori positivity (P = 0.03). Gastric cancer cases had significantly shorter telomere length (mean +/- SD relative telomere length, 1.25 +/- 0.34) than controls (1.34 +/- 0.35; P = 0.0008). Gastric cancer risk doubled [odds ratio (OR), 2.04; 95% confidence interval (95% CI), 1.33-3.13] among subjects in the shortest compared with the highest quartile of telomere length (P(trend) < 0.001). Telomere length-associated risks were higher among individuals with the lowest risk profile, those H. pylori-negative (OR, 5.45; 95% CI, 2.10-14.1), nonsmokers (OR, 3.07; 95% CI, 1.71-5.51), and individuals with high intake of fruits (OR, 2.43; 95% CI, 1.46-4.05) or vegetables (OR, 2.39; 95% CI, 1.51-3.81). Our results suggest that telomere length in peripheral leukocyte DNA was associated with H. pylori positivity, cigarette smoking, and dietary fruit intake. Shortened telomeres increased gastric cancer risk in this high-risk Polish population.

Background: Helicobacter pylori, a known risk factor of gastric cancer, rarely colonize the deeper portion of normal gastric glands, where the mucus is rich in alpha-1,4-linked N-acetylglucosamine capped O-glycans, that strongly inhibit H. pylori growth in vitro., Materials and Methods: We investigated the association between genetic variation in the O-glycan transferase encoding gene (a4GnT) and H. pylori infection and gastric cancer risk using a Polish population-based case-control study (273 gastric cancer patients and 377 controls)., Results: A haplotype at the rs2622694-rs397266 locus was associated with H. pylori infection, with the A-A haplotype associated with a higher risk compared with the most frequent G-G haplotype (odds ratio 2.30; 95% confidence interval 1.35-3.92). The association remained significant after correction for multiple tests (global p value: nominal 0.002, empirical 0.045). Neither this haplotype nor the tagSNPs were associated with overall gastric cancer risk., Conclusion: a4GnT genetic variation may be relevant to H. pylori infection, but not to gastric cancer risk.

Host genetic factors play an important role in modifying the risk of human disease, including cancers of the upper gastrointestinal tract, with increasing interest in Toll-like receptor (TLR) signaling and the impact of genetic polymorphisms in these systems. The CD14-159C/T and the TLR9-1237T/C promoter polymorphisms have previously been shown to be associated with various inflammatory conditions including Helicobacter pylori-induced gastritis in Caucasian populations. In this study, we assessed the association of these two functional single nucleotide polymorphisms with gastric cancer in two independent Caucasian population-based case-control studies of upper gastrointestinal tract cancer, initially in 312 noncardia gastric carcinoma cases and 419 controls and then in 184 noncardia gastric carcinomas, 123 cardia carcinomas, 159 esophageal cancers, and 211 frequency-matched controls. Odds ratios were computed from logistic models and adjusted for potential confounding factors. No significant association was found between the CD14-159C/T and the TLR9-1237T/C promoter polymorphisms and increased risk of gastric cancer. Neither single nucleotide polymorphism has been assessed in a Caucasian gastric cancer case-control study before; although the CD14-159C/T polymorphism has been reported to show no apparent association with H. pylori-related gastric malignancy in a Taiwanese Chinese population. In conclusion, although our earlier preliminary studies suggested that the CD14-159C/T and the TLR9-1237T/C promoter polymorphisms increase the risk of precancerous outcomes, they do not seem to increase the risk of gastric cancer itself. This discrepancy merits further examination.

Genetic variation in the androgen receptor (AR) gene may be associated with endometrial cancer risk based on the role of AR in regulating androgen levels. However, endometrial cancer studies reported inconsistent associations for a CAG repeat polymorphism in exon 1. Only one of these studies measured haplotype-tagging single nucleotide polymorphisms (htSNP) in AR and found statistically nonsignificant, decreased associations with endometrial cancer risk. In a population-based case-control study of 497 cases and 1,024 controls, we examined the CAG repeat polymorphism and six htSNPs (rs962458, rs6152, rs1204038, rs2361634, rs1337080, and rs1337082), which cover an estimated 80% of the known common variation in AR among Caucasian populations. CAG repeat length was not significantly associated with endometrial cancer [odds ratio per unit increase in the average number of repeats, 1.02 (95% confidence interval, 0.97-1.08); P(trend) = 0.29]. Minor alleles in three correlated htSNPs (rs6152, rs1204038, and rs1337082; r(2) >0.6) were associated with increased risk for endometrial cancer. The strongest association was observed for rs6152, with the odds ratios (95% confidence interval) being 1.13 (0.89-1.44) for heterozygous and 2.40 (1.28-4.51) for homozygous minor genotypes (P(trend) = 0.02) compared with homozygous major allele genotype. However, these associations were not statistically significant after permutation adjustment for multiple comparisons (P(trend) > 0.09). Haplotype analyses did not reveal any additional associations with endometrial cancer. Results from our study, taken together with previously published studies, provide little evidence of a consistent association between common genetic variation in AR and endometrial cancer risk.

Host immune responses are known determinants of gastric cancer susceptibility. We previously reported an increased gastric cancer risk associated with common variants of several T helper type 1 (Th1) cytokine genes in a population-based case-control study in Warsaw, Poland. In the present study, we augmented our investigation to include additional Th1 genes as well as key genes in the Th2 and Th3 pathways. Analysis of 378 cases and 435 age- and sex-matched controls revealed associations for polymorphisms in the Th1 IL7R gene and one polymorphism in the Th2 IL5 gene. The odd ratios (ORs) for IL7R rs1494555 were 1.4 [95% confidence interval (CI), 1.0-1.9] for A/G and 1.5 (95% CI, 1.0-2.4) for G/G carriers relative to A/A carriers (P = 0.04). The ORs for IL5 rs2069812 were 0.9 (95% CI, 0.7-1.3) for C/T and 0.6 (95% CI, 0.3-1.0) T/T carriers compared with C/C carriers (P = 0.03). These results suggest that IL5 rs2069812 and IL7R rs1389832, rs1494556 and rs1494555 polymorphisms may contribute to gastric cancer etiology.

Cervical cancer incidence and mortality in Poland is among the highest in Europe. To investigate infection with different human papillomaviruses (HPV) in Warsaw, Poland, we obtained cervical cell specimens from 834 women aged 18-59 years from the general population, and 88 cervical cancers. DNA of 44 HPV types was detected using a GP5+/6+-based PCR assay. HPV prevalence was 16.6% in the general female population, being highest (24.2%) in women aged 25-34 years, notably among unmarried women (37.3%). HPV prevalence fell to 8.6% at ages 55-59. High-risk HPV prevalence was 11.3%, with HPV16 being the most common type (3.7%). All but one cervical cancer were high-risk HPV-positive, although the importance of HPV16 (73%) was much greater, and multiple infections fewer (1%), than among HPV-positive women in the general female population. In summary, we report a relatively high burden of HPV infection in Warsaw, Poland, where 79% of cervical cancers are theoretically preventable by HPV16/18 vaccines.

Background: Epidemiologic studies have shown that breast cancer risk is reduced 30% to 40% in highly physically active compared with inactive women. However, the effects of moderate activities, timing of activities, and intervening effects of other risk factors remain less clear., Methods: We analyzed data on physical activity patterns in 2176 incident breast cancer cases and 2326 controls in a population-based breast cancer case-control study in Poland conducted in 2000-2003. Using unconditional logistic regression analyses, we calculated odds ratios (ORs) and 95% confidence intervals (CIs) associated with physical activity levels (measured by average metabolic equivalents of energy expenditure hours per week), controlling for potential confounders., Results: Total adult lifetime activity reduced risk of breast cancer, with individuals in the highest quartile having an OR of 0.80 (CI = 0.67-0.96) compared with the lowest quartile. Reduced risks were most consistent for the highest quartiles of moderate-to-vigorous activities: moderate/vigorous recreational activities (OR = 0.74; CI = 0.62-0.89), outdoor activities (0.81; 0.68-0.97), heavy physical work (0.60; 0.42-0.87), and combined high intensity (metabolic equivalent >6.0) activities (0.75; 0.63-0.90). These relations were not modified by body mass index, menopausal status, or family history of breast cancer. Reductions in risk with moderate/vigorous recreational activities were stronger for larger tumors and those with nodal involvement. Women who increased their recreational activity in their 50s had significantly reduced risk, with those in the highest tertile of change being at a 27% lower risk., Conclusions: Leisure-time moderate-to-vigorous activities reduce breast cancer risk irrespective of underlying host characteristics.

Summary: The inconsistent associations between fruit and vegetable intake and breast cancer risk may be due to heterogeneity of associations by estrogen (ER) and progesterone receptor (PR) status of the tumors. We evaluated this hypothesis in a large (2,386 cases and 2,503 controls) population-based case-control study in Poland, conducted between 2000 and 2003. We observed significant associations between reduced overall risk of breast cancer and increasing levels of total fruit intake (odds ratio (OR) for highest versus lowest quartile = 0.76, 95%CI = 0.63-0.91; p-trend = 0.01), but not for total vegetable intake (1.13 (0.93-1.37), p-trend = 0.25), after controlling for age, energy intake and known risk factors for breast cancer. The inverse association with total fruit intake was stronger for risk of ER+ (0.69 (0.54-0.88), p-trend = 0.01) than ER- tumors (0.89 (0.67-1.19), p-trend = 0.57) (p-heterogeneity = 0.02). In conclusion, this study suggests that fruit intake might have differential associations for breast tumor subtypes defined by ER status.

Germline mutations in the tumor suppressor gene TP53 are associated with high incidence of early-onset malignancies, and somatic mutations occur in 20-40% of all breast cancer cases. We investigated the association of common genetic variation in TP53 and its flanking genes, WDR79 and ATP1B2, with risk for breast cancer. Single nucleotide polymorphisms (SNPs) identified in a re-sequence analysis were genotyped in 2 large case-control studies including 731 cases and 1,124 controls from Norway, and 1,995 cases and 2,296 controls from Poland. Analyses of the pooled data showed no SNPs in TP53 to be significantly associated with risk for breast cancer. However, we found a significant and consistent association with risk for a SNP in exon 1 (R68G) of the 5' neighboring gene WDR79 (rs2287499, OR (95% CI) = 1.08 (0.95-1.23) for CG vs. CC and 1.60 (1.04-2.47) for GG vs. CC, p-trend = 0.01). Stratification by ER and PR status, showed these increases in risk to be limited to ER negative tumors (OR (95% CI) per variant allele: 1.42 (1.18-1.71) p-trend = 0.00009). In addition, 2 TP53 SNPs (rs17887200 3'of STP and rs12951053 in intron 7) showing weak and non-significant overall increases in risk, were also associated with ER negative tumors (1.48 (1.11-1.93) p-trend = 0.01 and 1.29 (1.06-1.58) p-trend = 0.009, respectively). In conclusion, this comprehensive evaluation of common genetic variation in TP53 and its flanking genes found no significant overall associations between SNPs in TP53 and breast cancer risk. However, data suggested that common variation in TP53 or WDR79 could be associated with ER negative breast cancers., ((c) 2007 Wiley-Liss, Inc.)

Background: Although a number of studies on the polymorphisms in COX1 and COX2 genes in association with risks for a number of cancers have been conducted, their relation to gastric cancer has not been well studied., Patients and Methods: Genotypes of several variants in both COX1 (Ex7+31 C>A and Ex10-4 G>A) and COX2 (-765 G>C, Ex10+837 T>C, Ex10-90 C>T, IVS5-275 T>G, and IVS7+111 T>C) were identified by TaqMan assays in 305 gastric cancer cases and 427 age- and gender-matched controls in a high-risk Polish population. Odds ratios for gastric cancer and 95% confidence intervals from unconditional logistic regression models were used to evaluate relative risks., Results: We found no statistically significant evidence that the polymorphisms tested in COX1 and COX2 are associated with gastric cancer risk., Conclusion: These results suggest that the polymorphisms examined in COX1 and COX2 do not affect the risk of gastric cancer.

Genetic variations increasing blood levels of acetaldehyde, the first metabolite of alcohol, refrain their carriers from drinking alcohol but may also put them at increased risk of cancer because of the mutagenic and carcinogenic effect of acetaldehyde. In a population-based study of 305 cases and 428 controls in Warsaw, Poland, we evaluated the effect of polymorphisms in alcohol metabolizing genes, including ADH1B (Ex9+5C>T, Ex3+23A>G, Ex3+58A>T and Ex9+77A>G), ADH1C (Ex8-56A>G and Ex6-14G>A) and ALDH2 (Ex1+82A>G), on levels of alcohol drinking and susceptibility of stomach cancer. We found that among control subjects frequency of alcohol drinking varied by alcohol metabolizing genotype. In particular, the weekly consumption of individuals carrying the AA, GA and GG genotypes of ALDH2 Ex1+82A>G polymorphism were 3.75, 2.26 and 1.53 drinks, respectively (p=0.04). However, none of the assessed polymorphisms in these 3 genes had a measurable effect on stomach cancer risk. When stratified by ALDH2 Ex1+82A>G polymorphism, alcohol-related increases in stomach cancer risk were restricted to individuals with the AG/GG genotypes, with a more than 2-fold risk among daily drinkers (OR=2.63, 95% CI=1.00-6.88) and 3-fold risk (OR=3.66, 95% CI=1.19-11.24) among those with 40 or more drink-years. In summary, our results suggested that the ALDH2 Ex1+82 G allele may be functionally deficient in eliminating acetaldehyde and discourage alcohol drinking. Furthermore, heavy drinkers of alcohol who were genetically prone to accumulate acetaldehyde may face an increased risk of stomach cancer., (Copyright (c) 2007 Wiley-Liss, Inc.)

Epidemiological evidence suggests that intake of folate and other B-vitamins and genetic variants in the one-carbon metabolism pathway could influence the risk of breast cancer. Previous studies have focused on 2 polymorphisms in the methylenetetrahydrofolate gene (MTHFR A222V and E429A); however, findings are inconclusive. In a large population-based case-control study in Poland (2,386 cases, 2,502 controls), we investigated the association between breast cancer risk and 13 polymorphisms in 6 one-carbon metabolism genes (MTHFR, MTR, MTRR, CBS, SHMT1 and SLC19A1). Data suggested an association between a nonsynonymous change in the gene coding for methionine synthase (MTR D919G) and reduced breast cancer risk: OR (95% CI) = 0.84 (0.73-0.96) and 0.85 (0.62-1.15) for heterozygous and homozygote variant genotypes, respectively, compared with common homozygotes; p-trend = 0.01, false discovery rate = 0.14. We found no significant associations between other variants and breast cancer risk, including MTHFR A222V or E429A. Meta-analyses including published studies of MTHFR A222V (8,330 cases and 10,825 controls) and E429A (6,521 cases and 8,515 controls) supported the lack of an overall association; however, studies suggested an increase in risk among premenopausal women. In conclusion, this report does not support a substantial overall association between the evaluated polymorphisms in the one-carbon metabolism pathway and breast cancer risk.

Analysis of gene expression data suggests that breast cancers are divisible into molecular subtypes which have distinct clinical features. This study evaluates whether pathologic features and etiologic associations differ among molecular subtypes. We evaluated 804 women with invasive breast cancers and 2,502 controls participating in a Polish Breast Cancer Study. Immunohistochemical stains for estrogen receptor alpha, progesterone receptor, human epidermal growth factor receptors (HER2 and HER1), and cytokeratin 5 were used to classify cases into five molecular subtypes: luminal A, luminal B, HER2-expresing, basal-like, and unclassified. Relative risks were estimated using adjusted odds ratios and 95% confidence intervals. We observed that compared with the predominant luminal A tumors (69%), other subtypes were associated with unfavorable clinical features at diagnosis, especially HER2-expressing (8%) and basal-like (12%) tumors. Increasing body mass index significantly reduced the risk of luminal A tumors among premenopausal women (odds ratios, 0.71; 95% confidence intervals, 0.57-0.88 per five-unit increase), whereas it did not reduce risk for basal-like tumors (1.18; 0.86-1.64; P(heterogeneity) = 0.003). On the other hand, reduced risk associated with increasing age at menarche was stronger for basal-like (0.78; 0.68-0.89 per 2-year increase) than luminal A tumors (0.90; 0.95-1.08; P(heterogeneity) = 0.0009). Although family history increased risk for all subtypes (except for unclassified tumors), the magnitude of the relative risk was highest for basal-like tumors. Results from this study have shown that breast cancer risk factors may vary by molecular subtypes identified in expression studies, suggesting etiologic, in addition to clinical, heterogeneity of breast cancer.

Background: The etiology of breast cancer is not well understood and the role of occupational exposures in breast carcinogenesis is still uncertain., Methods: The population-based case-control study included 2,386 incident breast cancer cases diagnosed in 2000-2003, and 2,502 controls. Lifetime occupational histories and information on other potential breast cancer risk factors were obtained through personal interviews. Conditional logistic regression analyses calculated odds ratios (ORs) associated with various occupations and industries after control for potential confounders., Results: We found statistically significant excesses of breast cancer among engineers (OR=2.0; 95% CI: 1.0-3.8), economists (2.1; 1.1-3.8), sales occupations-retail (1.2; 1.0-1.5), and other sales occupations (1.2; 1.0-1.5). Industries showing significantly elevated risks included special trade contractors (2.2; 1.2-4.3), electronic and electric equipment manufacturers (1.7; 1.1-2.7); and public administration/general government n.e.c. (2.7; 1.3-5.7). Each of these findings was supported by a statistically significant positive trend for duration of employment (P<0.05). A decreased breast cancer risk was observed in janitors and cleaners (0.7; 0.5-0.8)., Conclusions: In this study, we found few associations for breast cancer and occupations or industries. The suggestive findings for the electronic and electric equipment manufacturing industry and for the occupations with potential exposure to magnetic fields deserve further evaluation.

Helicobacter pylori infection, the dominant risk factor for gastric cancers, has been shown to elicit T helper type 1 (Th1) polarized immunological responses. We conducted a population-based study of 305 gastric cancer cases and 427 age- and gender-matched controls in Warsaw, Poland, to evaluate the association with several variants in genes responsible for Th1-cell-mediated response. Genotyping was performed on genomic DNA by TaqMan(TM) assays to determine TNFA (-308 G>A, -417 G>A, -555 G>A, -1036 C>T, -1042 C>A, -1210 T>C), IL1A (-889 C>T), IFNGR2 (Ex7-128 T>C, Ex2-34 C>G and Ex2-16 A>G) and IL12A (IVS2-798 T>A, IVS2-701 C>A and Ex7+277 G>A) polymorphisms. We used unconditional logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs), adjusting for sex, age, education and smoking status. Out of six single nucleotide polymorphisms (SNPs) tested in TNFA, gastric cancer risk was significantly associated with the TNFA (-308 G>A) polymorphism, with ORs of 1.4 (95% CI: 1.0-2.0) for the G/A and 2.5 (95% CI: 1.3-4.9) for the A/A genotype carriers, when compared with the more frequent genotype (G/G) (P-trend < 0.001). Among the three tested SNPs in the IFNGR2 gene, only the Ex7-128C>T polymorphism was associated with increased risk, with ORs of 1.5 (95% CI: 1.0-2.3) for T/C and 1.7 (95% CI: 1.1-2.7) for C/C carriers when compared with T/T carriers (P-trend = 0.01). Subjects carrying both IFNGR2 Ex7-128 C/C and TNFA -308 A/A genotypes had the highest risk (OR = 5.5, 95% CI: 1.5-19.4), although the interaction was not statistically significant. IL1A (-889 C>T) and the three examined IL12A variants were unrelated to gastric cancer risk. Our findings suggest that two Th1-related polymorphisms (TNFA -308 A>G and IFNGR2 Ex7-128 C>T) may increase the risk of gastric cancer.

High estrogen exposure in utero may increase breast cancer risk later in life. However, studies of the associations between perinatal factors presumed to affect the fetal hormonal environment and breast cancer risk are inconsistent. We used data from a population-based case-control study of 2,386 incident breast cancers and 2,502 controls in Poland to evaluate risks associated with various perinatal characteristics. After adjusting for confounders, we found a significant trend (p = 0.01) of breast cancer risk with birth weight (OR = 1.54, 95% CI 1.08-2.19 for birth weights >4,000 g vs. <2,500 g). Subjects with a high birth order (> or =6) were at reduced risk (OR = 0.81, 0.61-1.06) when compared with first born subjects. Birth weight was somewhat a stronger risk predictor among subjects whose cancers were diagnosed at 50 years of age or older (OR = 1.84, 1.19-2.85) than among those with cancers diagnosed at younger ages (OR = 1.14, 0.61-2.12). Subjects whose mothers smoked during their pregnancies were at slightly higher risk than those who never smoked (OR = 1.21, 0.99-1.47), but the risk was similar to mothers who only smoked at other times (OR = 1.22, 0.81-1.84). Breast cancer risk was not related to paternal smoking, maternal age, gestational age or twin status. Our results add support to the growing evidence that some perinatal exposures may relate to breast cancer risk. Additional studies are needed to confirm associations and clarify the biologic mechanisms underlying these associations.

Because catechol-O-methyltransferase (COMT) catalyzes the addition of methyl groups to stabilize catechol estrogens that may induce DNA damage, genetic variants could influence breast cancer risk. To comprehensively characterize genetic variation in this gene, we selected haplotype-tagging single nucleotide polymorphisms (htSNP) in COMT. A total of 11 htSNPs (including COMT Val(158)Met) were selected based on the resequencing and dense genotyping approach of the Breast and Prostate Cancer Cohort Consortium. htSNPs were genotyped in a population-based, case-control study in Poland (1,995 cases and 2,296 controls). Individual SNPs were not significantly associated with risk. Haplotypes were estimated using the expectation-maximization algorithm. Overall differences in the haplotype distribution between cases and controls were assessed using a global score test. The TGAG haplotype (frequent in 4.3% of controls), in a linkage disequilibrium (LD) block that included the 3' untranslated region (UTR) of COMT, was associated with breast cancer risk (odds ratio, 1.29; 95% confidence interval, 1.06-1.58) compared with the most common haplotype TGAA; however, the global test for haplotype associations was not significant (P = 0.09). Haplotypes in another LD block, which included COMT Val(158)Met, were not associated with breast cancer risk (global P = 0.76). Haplotype-breast cancer risk associations were not significantly modified by hormonally related risk factors, family history of breast cancer, or tumor characteristics. In summary, our data does not support a substantial overall association between COMT haplotypes and breast cancer. The suggestion of increased risk associated with a haplotype in the 3' UTR of COMT needs to be confirmed in independent study populations.

Exposure to ionizing radiation (IR) results in various types of DNA damage and is a suspected cause of lung cancer. An essential cellular machinery against DNA damage is cell cycle control, which is regulated by several genes, including TP53, CCND1, and CDKN2A. Therefore, we hypothesized that the genetic variants in these three genes influence the predisposition of lung cancer (i.e., CCND1 G870A, CDKN2A Ala(148)Thr, TP53 Arg(72)Pro, and 16-bp repeat in intron 3) and that the effect of X-ray on lung cancer risk can be modified by the presence of these genetic variations. The study was conducted in 15 centers in 6 countries of Central Europe between 1998 and 2002. A total of 2,238 cases and 2,289 controls were recruited and provided DNA samples. Cases with positive family history were analyzed separately. The joint effect of X-ray and previous risk genotypes was assessed, and modification by sequence variants on X-ray dose-response relationship with lung cancer risk was evaluated. We found an overall effect of TP53 intron 3 16-bp repeats [odds ratio (OR), 1.99; 95% confidence interval (95% CI), 1.27-3.13], which was stronger among cases with family history of lung cancer (OR, 2.98; 95% CI, 1.29-6.87). In addition, our results suggested an interaction that was greater than multiplicativity between TP53 intron 3 16-bp repeats and multiple X-ray exposures (interaction OR, 5.69; 95% CI, 1.33-24.3). We did not observe a main effect of CCND1 G870A polymorphism; however, the dose-response relationship between lung cancer risk and X-ray exposures was modified by CCND1 genotype with no risk from X-ray exposures among subjects who carried G/G genotype, intermediate risk [trend OR for X-ray, 1.16; 95% CI, 1.05-1.27) among subjects with G/A genotype, and highest risk [trend OR for X-ray, 1.29; 95% CI, 1.12-1.49) among subjects with A/A genotype. Sequence variants in cell cycle control pathway may increase the risk of lung cancer and modify the risk conferred by multiple X-ray exposures. However, a definite conclusion can only be drawn on replication by different studies among individuals who are highly exposed to IR.

Four single nucleotide polymorphisms (SNPs) in CYP1B1 (Ex2 + 143 C > G, Ex2 + 356 G > T, Ex3 + 251 G > C, Ex3 + 315 A > G) cause amino acid changes (R48G, A119S, L432V and N453S, respectively) and are associated with increased formation of catechol estrogens; however, epidemiologic evidence only weakly supports an association between these variants and breast cancer risk. Because genetic variability conferring increased susceptibility could exist beyond these putative functional variants, we comprehensively examined the common genetic variability within CYP1B1. A total of eight haplotype-tagging (ht)SNPs (including Ex3 + 315 A > G), in addition to two putatively functional SNPs (Ex2 + 143 C > G and Ex3 + 251 G > C), were selected and genotyped in a large case-control study of Polish women (1995 cases and 2296 controls). Haplotypes were estimated using the expectation-maximization algorithm, and overall differences in the haplotype distribution between cases and controls were assessed using a global score test. We also evaluated levels of tumor CYP1B1 protein expression in a subset of 841 cases by immunohistochemistry, and their association with genetic variants. In the Polish population, we observed two linkage disequilibrium (LD)-defined blocks. Neither haplotypes (global P-value of 0.99 and 0.67 for each block of LD, respectively), nor individual SNPs (including three putatively functional SNPs) were associated with breast cancer risk. CYP1B1 was expressed in most tumor tissues (98%), and the level of expression was not related to the studied genetic variants. We found little evidence for modification of the estimated effect of haplotypes or individual SNPs by age, family history of breast cancer, or tumor hormone receptor status. The present study provides strong evidence against the existence of a substantial overall association between common genetic variation in CYP1B1 and breast cancer risk.

Breast cancer is a morphologically and clinically heterogeneous disease; however, it is less clear how risk factors relate to tumour features. We evaluated risk factors by tumour characteristics (histopathologic type, grade, size, and nodal status) in a population-based case-control of 2386 breast cancers and 2502 controls in Poland. Use of a novel extension of the polytomous logistic regression permitted simultaneous modelling of multiple tumour characteristics. Late age at first full-term birth was associated with increased risk of large (> 2 cm) tumours (odds ratios (95% confidence intervals) 1.19 (1.07-1.33) for a 5-year increase in age), but not smaller tumours (P for heterogeneity adjusting for other tumour features (Phet) = 0.007). On the other hand, multiparity was associated with reduced risk for small tumours (0.76 (0.68-0.86) per additional birth; Phet = 0.004). Consideration of all tumour characteristics simultaneously revealed that current or recent use of combined hormone replacement therapy was associated with risk of small (2.29 (1.66-3.15)) and grade 1 (3.36 (2.22-5.08)) tumours (Phet = 0.05 for size and 0.0008 for grade 1 vs 3), rather than specific histopathologic types (Phet = 0.63 for ductal vs lobular). Finally, elevated body mass index was associated with larger tumour size among both pre- and postmenopausal women (Phet = 0.05 and 0.0001, respectively). None of these relationships were explained by hormone receptor status of the tumours. In conclusion, these data support distinctive risk factor relationships by tumour characteristics of prognostic relevance. These findings might be useful in developing targeted prevention efforts.

Homozygous mutation in the ATM gene causes ataxia telangiectasia and heterozygous mutation carriers may be at increased risk of breast cancer. We studied a total of 22 ATM variants; 18 variants were analyzed in one of two large population-based studies from the U.S. and Poland, and four variants were analyzed in all 2,856 breast cancer cases and 3,344 controls from the two studies. The missense mutation Ser49Cys (c.146C>G, p.S49C), carried by approximately 2% of subjects, was more common in cases than controls in both study populations, combined odds ratio (OR) 1.69 (95% CI, 1.19-2.40; P=0.004). Another missense mutation at approximately 2% frequency, Phe858Leu (c.2572T>C, p.F858L), was associated with a significant increased risk in the U.S. study but not in Poland, and had a combined OR of 1.44 (95% CI, 0.98-2.11; P=0.06). These analyses provide the most convincing evidence thus far that missense mutations in ATM, particularly p.S49C, may be breast cancer susceptibility alleles. Because of their low frequency, even larger sample sizes are required to more firmly establish these associations., (Copyright 2006 Wiley-Liss, Inc.)

Impaired base-excision repair (BER) function can give rise to the accumulation of DNA damage and initiation of cancer. We evaluated whether genetic variation in six BER pathway genes (XRCC1, ADPRT, APEX1, OGG1, LIG3, and MUTYH) is associated with breast cancer risk in two large population-based case-control studies in the United States (3,368 cases and 2,880 controls) and Poland (1,995 cases and 2,296 controls). A detailed evaluation was first done in a subset of 1,898 cases and 1,514 controls with mouthwash DNA samples in the U.S. study. Significant findings were followed up in the remainder of the U.S. study population that provided cytobrush DNA samples and in the Polish study. Using data from U.S. study participants with mouthwash DNA, we found no significant overall association between breast cancer risk and XRCC1 R280H and R194W, ADPRT V726W, APEX1 D148E, OGG1 S326C, LIG3 R780H, or MUTYH 5' untranslated region. These data suggested a decreased risk for XRCC1Q399R homozygous variants compared with homozygous wild-type in premenopausal women, but these findings were not confirmed when data from cytobrush DNA samples were added [combined odds ratio (OR), 0.8; 95% confidence interval (95% CI), 0.6-1.1] or in the Polish study (OR, 1.0; 95% CI, 0.7-1.5). Meta-analyses based on our data and published data from studies of two single nucleotide polymorphisms in XRCC1 showed no evidence of an overall association between breast cancer risk and homozygous variants versus wild-type for Q399R (OR, 1.1; 95% CI, 1.0-1.2) or R194W (OR, 1.0; 95% CI, 0.7-1.8), although there was a suggestion for an association in Asian populations for Q399R (OR, 1.6; 95% CI, 1.1-2.4; P = 0.02). In conclusion, our results do not support that the polymorphisms evaluated in six BER pathway genes play a major role in breast carcinogenesis, particularly in Caucasian populations.

Impaired DNA repair capacity may adversely affect cancer risk, particularly in subjects exposed to DNA damaging carcinogens, as found in tobacco smoke, or among subjects deficient for protective factors, as found in fruits and vegetables. We studied tobacco use, fruit and vegetable intake, and common non-synonymous single nucleotide polymorphisms in four DNA repair genes in relation to gastric cancer risk, in a population-based, case-control study of 281 incident gastric cancer cases and 390 controls, in Warsaw, Poland. Multivariate logistic regression analysis was performed to calculate odds ratios (OR) and 95% confidence intervals (CI). Increased risks of gastric cancer were found for smokers (OR=3.1, CI=1.9-5.1 for pack-years>or=40 versus never smokers) and subjects with low fruit intake (OR=2.2, CI=1.3-3.6 for 1st versus 4th quartile); risk associated with vegetable intake was not statistically significant. Allele frequencies among the controls were consistent with those previously reported for the 5 polymorphisms studied: XRCC1-Arg399Gln, XPD-Lys751Gln, MGMT-Ile143Val, Leu84Phe, and XRCC3-Thr241Met. None of the studied polymorphisms were independently associated with gastric cancer risk. Smoking-associated risks, however, were greatest for carriers of the XRCC1-399 ArgArg genotype (Pinteraction=0.004). Risks associated with low intake of fruits or vegetables tended to be modified by selected polymorphisms in XRCC1, XPD and MGMT (Pinteraction=0.1-0.2). Risk modification was not found for the other repair polymorphisms. Selected DNA repair polymorphisms did not have independent effects on gastric cancer risk; however, they may modify smoking- and probably diet-related risks for this disease. These results need replication in larger epidemiological studies of gastric cancer.

Background: In spite of the dramatic decline in the incidence of stomach cancer in the twentieth century, Poland has one of the highest rates in the world., Aims: To evaluate the risk of stomach cancer by grouped occupations and industries, as well as by some specific occupational exposures., Methods: Cases (n = 443) were newly diagnosed with stomach adenocarcinomas between 1994 and 1996. Controls (n = 479) were randomly selected from the general population in Warsaw., Results: Only a few occupations and industries were associated with significantly increased risks of stomach cancer. The most suggestive finding was for work in the leather goods industry. Risk was also significantly increased among men working in fabricated metal production and among women ever employed as managers and governmental officials. Men ever employed as teaching professionals and women employed as technical and science professionals had significantly decreased risks of stomach cancer. Among men, a significant positive trend in risk with duration of employment was observed for work in the leather industry and special trade construction. No significantly increased risks were observed for specific exposures assessed by a job-exposure matrix or by self-reports. However among men there were non-significantly increased risks with 10 or more years exposure to asbestos, metal dust, and nitrosamines assessed by a job-exposure matrix., Conclusions: Employment in the leather goods industry, special trade construction, and metal fabrication was associated with an increased risk of stomach cancer among men. However, there were only weak associations with specific exposures. Occupational exposures do not contribute substantially to the high rates of stomach cancer in Poland.

Background: Manganese superoxide dismutase (MnSOD) plays a critical role in the detoxification of mitochondrial reactive oxygen species, constituting a major cellular defense mechanism against agents that induce oxidative stress. A genetic polymorphism in the mitochondrial targeting sequence of this gene has been associated with increased cancer risk. This one base pair transition (-9 T>C) leads to a Val to Ala amino acid change in the mitochondrial targeting sequence. In addition, the MnSOD promoter contains an activator protein-2 (AP-2) binding site that modifies transcription of MnSOD. Mutations have been identified in the proximal region of the promoter in human tumor cell lines. One of these mutations (-102 C>T) has been shown to change the binding pattern of AP-2, leading to a reduction in transcriptional activity. The aim of our study was to investigate possible associations of the (-9 T>C) and (-102 C>T) polymorphisms with gastric cancer in a population-based case-control study conducted in Warsaw, Poland., Materials and Methods: DNA was obtained from a population based case-control study of stomach cancer conducted in Warsaw, Poland, between 1994 and 1996. The MnSOD -9 T>C genotype was determined by PCR-RFLP assay. The MnSOD -102 C>T genotype was determined using a TaqMan allele discrimination assay., Results: The frequency of the -102 C>T polymorphism was 41% (38/91) in gastric cancer cases and 38% (50/130) in the controls (odds ratio [OR] 1.1, 95% confidence interval [CI] 0.6-2.1). The frequency of the -9 T>C polymorphism was 44% (202/464) in cases and 56% (262/464) in controls (OR 1.1; 95% CI 0.9-1.37). The lack of association was observed in both non-smokers (OR 1.5; 95% CI 0.7-2.34) and smokers (OR 1.1; 95% CI 0.7-1.7). Furthermore, the association was not significant when smokers were segregated by extent of smoking history., Conclusion: The association of the manganese superoxide dismutase polymorphisms at -102 C>T and the -9 T>C were not found to be associated with gastric cancer in a Polish case-control study.

Immunohistochemical characterization of tumor tissues in epidemiological studies is a promising approach to identify breast cancer subtypes with distinct etiology. The recent development of the tissue microarray (TMA) technique allows for standardized, rapid, and cost-effective immunohistochemical characterization of many cases, which is critical in epidemiological studies. Sectioning paraffin blocks at different times results in loss of material, which can be reduced by preparing many sections each time a block is cut. However, data suggest that staining intensity declines in whole sections prepared from conventional paraffin blocks with storage time, resulting in false-negative results. This problem would be accentuated in TMAs because of the limited tissue representation of each case. To evaluate this concern, we prepared a single TMA block from 125 invasive breast carcinomas collected in a population-based case-control study conducted in Poland and compared estrogen receptor (ER-alpha), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) expression in sections cut and stored for 6 months at room temperature with sections cut from the same TMA block and stained on the same day. Percentage of positive cases for stored versus fresh sections was similar for ER (59.0%) but significantly higher in fresh sections for PR (56.3% versus 64.1%, P = 0.01) and HER2 (45.5% versus 64.4%, P < 0.001). Among cases positive in both stored and fresh sections, the median percentage of immunoreactive cells was significantly reduced and the staining intensity was consistently lower in stored compared with fresh sections. We conclude that loss of immunoreactivity is an important problem in TMAs of breast cancer. Improved methods for sectioning TMAs and storing tissue sections aimed at reducing loss of immunoreactivity are critical for the use of TMAs in epidemiological studies.

The effect of smoking, drinking, diet, dental care and sexual habits on the risk of oral and pharyngeal cancer was investigated in a case-control study conducted in Warsaw, Poland. The study comprised 122 patients (including 44 females) aged 23-80 years with histologically confirmed cancer of oral cavity and pharynx. Controls were 124 subjects (including 52 females) admitted to the hospital for different non-neoplastic conditions unrelated to tobacco and alcohol consumption, with frequency matched to cases by age and sex. Smoking and drinking were strongly associated with an increased risk of oral cancer. Among consumers of both products, risks of oral cancer tended to combine in a multiplicative fashion and were increased more than 14-fold among those who consumed more than 15 cigarettes and seven or more drinks per day. Cessation of smoking was associated with reduced risk of this cancer. The risks varied by type of cigarettes smoked, being lower among those consuming filtered cigarettes only (OR = 1.6) than nonfilter (OR = 6.5) or mixed (OR = 4.2) cigarettes. High fruit intake was associated with significantly decreased risk (OR = 0.4) with the strongest significant inverse association found for fruit juices and citrus fruits ( < 0.01). After adjustment for tobacco smoking and alcohol drinking, poor dentition as evidenced by missing teeth, frequency of dental check-ups and frequency of teeth brushing emerged as a strong risk factor. Number of missing teeth and frequency of dental check-ups and frequency of tooth brushing showed increased ORs of 9.8, 11.9 and 3.2, respectively. Denture wearing did not affect oral cancer risk. No differences were detected in sexual practices (including oral sex and intercourse with prostitutes). In terms of attributable risk, smoking accounted for 57% of oral cancer cases in Poland, alcohol for 31% and low fruit intake for 12%. Attributable risks for low frequency of tooth brushing and dental check-ups were 56% and 47%, respectively. In conclusion, smoking and drinking cessation and increase of fresh fruit intake are likely to be effective preventive measures against oral cancer. These findings indicate also that poor oral hygiene may be an independent risk factor.

Glutathione S-transferases are important in the detoxification of a wide range of human carcinogens. Previous studies have shown inconsistent associations between the GSTT1 and GSTM1 null genotypes and stomach cancer risk. We investigated the relationship between these and related genotypes and stomach cancer risk in a population-based case-control study in Warsaw, Poland, where stomach cancer incidence and mortality rates are among the highest in Europe. DNA from blood samples was available for 304 stomach cancer patients and 427 control subjects. We observed a 1.48-fold increased risk for stomach cancer (95% confidence interval 0.97-2.25) in patients with the GSTT1 null genotype but no evidence of increased risk associated with the GSTM1, GSTM3 or GSTP1 genotypes. Furthermore, the stomach cancer risk associated with the GSTT1 null genotype varied by age at diagnosis, with odds ratios of 3.85, 1.91, 1.78 and 0.59 for those diagnosed at ages less than 50, 50-59, 60-69 and 70 years or older, respectively (P trend = 0.01). This was due to a shift in the GSTT1 genotype distribution across age groups among stomach cancer patients only. These results suggest that the GSTT1 null genotype may be associated with increased risk of stomach cancer.