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Tongzhang Zheng

Publications and source records attributed to Tongzhang Zheng.

At least 19 recordsLinked to original sources

Ala394Thr polymorphism in the clock gene NPAS2: a circadian modifier for the risk of non-Hodgkin's lymphoma.

Circadian disruption is theorized to cause immune dysregulation, which is the only established risk factor for non-Hodgkin's lymphoma (NHL). Genes responsible for circadian rhythm are also involved in cancer-related biological pathways as potential tumor suppressors. However, no previous studies have examined associations between circadian genes and NHL risk. In this population-based case control study (n = 455 cases; 527 controls), we examined the only identified nonsynonymous polymorphism (Ala394Thr; rs2305160) in the largest circadian gene, neuronal PAS domain protein 2 (NPAS2), in order to examine its impact on NHL risk. Our results demonstrate a robust association of the variant Thr genotypes (Ala/Thr and Thr/Thr) with reduced risk of NHL (OR = 0.66, 95% CI: 0.51-0.85, p = 0.001), especially B-cell lymphoma (OR = 0.61, 95% CI: 0.47-0.80, p <or= 0.0001). These findings provide the first molecular epidemiologic evidence supporting a role of circadian genes in lymphomagenesis, which suggests that genetic variations in circadian genes might be a novel panel of promising biomarkers for NHL and warrants further investigation.

Aged↗

Family history of hematopoietic and non-hematopoietic malignancies and risk of non-Hodgkin lymphoma.

BACKGROUND: Family history of hematopoietic malignancies has been linked to the risk of non-Hodgkin lymphoma (NHL). The relationship between family history of specific hematopoietic and non-hematopoietic malignancies and the risk of NHL and by NHL subtypes are unclear. METHODS: We analyzed data from a population-based case-control study in Connecticut women. A total of 601 histologically confirmed NHL incident cases and 717 randomly selected controls were included in the study. Unconditional logistic regression was used to estimate the association between family cancer history and risk of NHL overall and by NHL subtypes. RESULTS: Compared to women who reported to have no family history of any malignancies in first-degree relatives, those who reported to have a family history of lymphoma (OR = 2.2, 95%CI: 1.1-4.5) or leukemia (OR = 2.5, 95%CI: 1.2-5.2) had an increased risk of NHL. The risk was higher among women who had a sibling with lymphoma or leukemia than those who had parents with lymphoma or leukemia. Several non-hematopoietic malignancies in first-degree relatives, including cancer of the lung (OR = 1.7, 95%CI: 1.1-2.6) in first-degree relatives, stomach (OR = 2.2, 95%CI: 0.8-5.9) and pancreas (OR = 2.6, 95%CI: 0.9-7.1) in parents, as well as liver (OR = 5.0, 95%CI: 1.0-24.6), breast (OR = 2.2, 95%CI: 1.3-3.9), cervix (OR = 7.5, 95%CI: 0.9-64.9), and ovary (OR = 3.5, 95%CI: 1.1-11.5) in siblings were also associated with an increased risk of NHL. CONCLUSIONS: The risk associated with a family history of malignancies in first degree-relatives appears to vary by type of first-degree relatives.

Case-Control Studies↗

Family history of hematopoietic malignancies and risk of non-Hodgkin lymphoma (NHL): a pooled analysis of 10 211 cases and 11 905 controls from the International Lymphoma Epidemiology Consortium (InterLymph).

A role for genetic susceptibility in non-Hodgkin lymphoma (NHL) is supported by the accumulating evidence of common genetic variations altering NHL risk. However, the pattern of NHL heritability remains poorly understood. We conducted a pooled analysis of 10 211 NHL cases and 11 905 controls from the International Lymphoma Epidemiology Consortium (InterLymph) to evaluate NHL risk among those with hematopoietic malignancies in first-degree relatives. Odds ratios (ORs) and 95% confidence intervals (CIs) of NHL and its subtypes were estimated from unconditional logistic regression models with adjustment for confounders. NHL risk was elevated for individuals who reported first-degree relatives with NHL (OR = 1.5; 95% CI = 1.2-1.9), Hodgkin lymphoma (OR = 1.6; 95% CI = 1.1-2.3), and leukemia (OR = 1.4; 95% CI = 1.2-2.7). Risk was highest among individuals who reported a brother with NHL (OR = 2.8; 95% CI = 1.6-4.8) and was consistent for all NHL subtypes evaluated. If a first-degree relative had Hodgkin lymphoma, NHL risk was highest if the relative was a parent (OR = 1.7; 95% CI = 1.0-2.9). If a first-degree relative had leukemia, NHL risk was highest among women who reported a sister with leukemia (OR = 3.0; 95% CI = 1.6-5.6). The pattern of NHL heritability appeared to be uniform across NHL subtypes, but risk patterns differed by specific hematopoietic malignancies and the sex of the relative, revealing critical clues to disease etiology.

Case-Control Studies↗

Genetic polymorphisms in the oxidative stress pathway and susceptibility to non-Hodgkin lymphoma.

Oxidative damage caused by reactive oxygen species (ROS) and other free radicals is involved in a number of pathological conditions including cancer. In a population-based case-control study of non-Hodgkin lymphoma (NHL) (n = 518 cases, 597 controls) among women in Connecticut, we analyzed one or more single nucleotide polymorphisms (SNPs) in ten candidate genes (AKR1A1, AKR1C1, AKR1C3, CYBA, GPX1, MPO, NOS2A, NOS3, OGG1, and SOD2) that mediate oxidative stress directly or indirectly in the NADPH oxidase-dependent respiratory burst. Odds ratios (OR) and 95% confidence intervals (CI) were adjusted for age and race. Polymorphisms in AKR1A1 and CYBA were significantly associated with increased risk of NHL. There was a 1.7-fold (95% CI = 1.2-2.4, P = 0.0047) increased risk of NHL for individuals who were variant homozygous for the AKR1A1 (IVS5 + 282T > C) SNP. The effect was most pronounced for risk of diffuse large B-cell lymphoma, but risk estimates were non-significantly elevated for other common B-cell histologies and T-cell lymphomas as well. In addition, individuals variant homozygous for the CYBA (Ex4 + 11C > T) SNP had a 1.6-fold (95% CI = 1.1-2.4, P = 0.019) increased risk of NHL that was particularly pronounced for T-cell lymphoma (OR = 3.5, 95% CI = 1.3-9.6, P = 0.013), but was also associated with non-significant increased risks for each of the common B-cell histologies. These results suggest that SNPs in genes related to the oxidative stress pathway may be associated with increased risk of NHL.

Adult↗

Risk of multiple myeloma following medication use and medical conditions: a case-control study in Connecticut women.

BACKGROUND: Certain commonly used drugs and medical conditions characterized by chronic immune dysfunction and/or antigen stimulation have been suggested to affect important pathways in multiple myeloma tumor cell growth and survival. We conducted a population-based case-control study to investigate the role of medical history in the etiology of multiple myeloma among Connecticut women. METHODS: A total of 179 incident multiple myeloma cases (21-84 years, diagnosed 1996-2002) and 691 population-based controls was included in this study. Information on medical conditions, medications, and medical radiation was obtained by in-person interviews. We calculated odds ratios (OR) as measures of relative risks using logistic regression models. RESULTS: A reduced multiple myeloma risk was found among women who had used antilipid statin therapy [OR, 0.4; 95% confidence interval (95% CI), 0.2-0.8] or estrogen replacement therapy (OR, 0.6; 95% CI, 0.4-0.99) or who had a medical history of allergy (OR, 0.4; 95% CI, 0.3-0.7), scarlet fever (OR, 0.5; 95% CI, 0.2-0.9), or bursitis (OR, 0.4; 95% CI, 0.2-0.7). An increased risk of multiple myeloma was found among women who used prednisone (OR, 5.1; 95% CI, 1.8-14.4), insulin (OR, 3.1; 95% CI, 1.1-9.0), or gout medication (OR, 6.7; 95% CI, 1.2-38.0). CONCLUSIONS: If our results are confirmed, mechanistic studies examining how prior use of insulin, prednisone, and, perhaps, gout medication might promote increased occurrence of multiple myeloma and how antilipid statins, estrogen replacement therapy, and certain medical conditions might protect against multiple myeloma may provide insights to the as yet unknown etiology of multiple myeloma.

Adult↗

Genetic variants in caspase genes and susceptibility to non-Hodgkin lymphoma.

The caspase proteins are essential for the regulation of normal B cell development and regulation of apoptosis. We investigated five single nucleotide polymorphisms in four key caspase genes, CASP3 [Ex8-280C>A (rs6948) and Ex8+567T>C (rs1049216)], CASP8 Ex14-271A>T (rs13113), CASP9 Ex5+32G>A (rs1052576) and CASP10 Ex3-171A>G (rs3900115) to determine whether they alter risk for non-Hodgkin lymphoma (NHL) in a population-based case-control study of women in Connecticut (461 cases and 535 controls). Variants in CASP3 and CASP9 were significantly associated with a decreased risk for NHL, particularly follicular lymphoma [e.g. CASP3 Ex8+567T>C odds ratio (OR)(CC+TC) = 0.4, 95% confidence interval (CI) = 0.3-0.7; and CASP9 Ex5+32G>A OR(AA+AG) = 0.6, 95% CI = 0.4-1.0]. Further, variants in CASP3, CASP8 and CASP10 were associated with a decreased risk of marginal zone lymphoma and variants in CASP3 and CASP10 were associated with a lower risk of chronic lymphocytic leukemia and related subtypes. The striking protective associations observed for polymorphisms in all four genes for NHL and/or one or more subtypes suggest that genetic variation in CASP genes may play an important role in the etiology of NHL.

Adult↗

Polymorphisms in DNA repair genes and risk of non-Hodgkin lymphoma among women in Connecticut.

Several hereditary syndromes characterized by defective DNA repair are associated with high risk of non-Hodgkin lymphoma (NHL). To explore whether common polymorphisms in DNA repair genes affect risk of NHL in the general population, we evaluated the association between single nucleotide polymorphisms (SNPs) in DNA repair genes and risk of NHL in a population-based case-control study among women in Connecticut. A total of 518 NHL cases and 597 controls recruited into the study provided a biologic sample. Thirty-two SNPs in 18 genes involved in several DNA repair pathways were genotyped. Genotype data were analyzed by unconditional logistic regression adjusting for age and race. SNPs in four genes (ERCC5, ERCC2, WRN, and BRCA1) were associated with altered risk of NHL and diffuse large B-cell lymphoma (DLBCL), the major B cell subtype. In particular, ERCC5 Asp1104His was associated with increased risk of NHL overall (OR: 1.46; 95% CI: 1.13-1.88; P=0.004), DLBCL (OR: 1.44; 95% CI: 0.99-2.09; P=0.058), and also T cell lymphoma. WRN Cys1367Arg was associated with decreased risk of NHL overall (OR: 0.71; 95% CI: 0.56-0.91; P=0.007) and DLBCL (OR: 0.66; 95% CI: 0.45-0.95; P=0.024), as well as follicular and marginal zone lymphomas. Genetic polymorphisms in DNA repair genes, particularly ERCC5 and WRN, may play a role in the pathogenesis of NHL, especially for DLBCL. Further work is needed to extend these findings by carrying out extended haplotype analyses of these and related genes and to replicate the observations in other studies.

Adult↗

Cytokine polymorphisms in the Th1/Th2 pathway and susceptibility to non-Hodgkin lymphoma.

Studies have demonstrated that common polymorphisms in Th1 and Th2 cytokine genes can alter gene expression, modulate the balance between Th1/Th2 responsiveness, and influence susceptibility for autoimmune disorders, infectious diseases, and cancer. We analyzed one or more single nucleotide polymorphisms (SNPs) in 20 candidate Th1/Th2 genes in a population-based case-control study of non-Hodgkin lymphoma (NHL; n = 518 cases, 597 controls) among women in Connecticut. SNPs in critical genes, IL4, IL5, IL6, and IL10, were associated with risk for NHL and in some instances with a specific histologic subtype. Analysis of 4 SNPs in the IL10 promoter (-3575T>A, -1082A>G, -819C>T, and -592C>A) revealed that both the AGCC haplotype (odds ratio [OR] = 1.54, 95% confidence interval [CI] = 1.21-1.96, P < .001) and the TATA haplotype (OR = 1.37, 95% CI = 1.05-1.79, P = .02) were associated with increased risk for B-cell lymphomas. In contrast, the IL4-1098G allele was associated with increased risk of T-cell lymphomas (OR = 3.84; 95% CI = 1.79-8.22; P < .001). Further, the IL10 and IL4 SNP associations remained significant after adjusting for multiple comparisons. These results suggest that SNPs in Th2 cytokine genes may be associated with risk of NHL.

Adult↗

Genetic variation in TNF and IL10 and risk of non-Hodgkin lymphoma: a report from the InterLymph Consortium.

BACKGROUND: Common genetic variants in immune and inflammatory response genes can affect the risk of developing non-Hodgkin lymphoma. We aimed to test this hypothesis using previously unpublished data from eight European, Canadian, and US case-control studies of the International Lymphoma Epidemiology Consortium (InterLymph). METHODS: We selected 12 single-nucleotide polymorphisms for analysis, on the basis of previous functional or association data, in nine genes that have important roles in lymphoid development, Th1/Th2 balance, and proinflammatory or anti-inflammatory pathways (IL1A, IL1RN, IL1B, IL2, IL6, IL10, TNF, LTA, and CARD15). Genotype data for one or more single-nucleotide polymorphisms were available for 3586 cases of non-Hodgkin lymphoma and for 4018 controls, and were assessed in a pooled analysis by use of a random-effects logistic regression model. FINDINGS: The tumour necrosis factor (TNF) -308G-->A polymorphism was associated with increased risk of non-Hodgkin lymphoma (p for trend=0.005), particularly for diffuse large B-cell lymphoma, the main histological subtype (odds ratio 1.29 [95% CI 1.10-1.51] for GA and 1.65 [1.16-2.34] for AA, p for trend <0.0001), but not for follicular lymphoma. The interleukin 10 (IL10) -3575T-->A polymorphism was also associated with increased risk of non-Hodgkin lymphoma (p for trend=0.02), again particularly for diffuse large B-cell lymphoma (p for trend=0.006). For individuals homozygous for the TNF -308A allele and carrying at least one IL10 -3575A allele, risk of diffuse large B-cell lymphoma doubled (2.13 [1.37-3.32], p=0.00083). INTERPRETATION: Common polymorphisms in TNF and IL10, key cytokines for the inflammatory response and Th1/Th2 balance, could be susceptibility loci for non-Hodgkin lymphoma. Moreover, our results underscore the importance of consortia for investigating the genetic basis of chronic diseases like cancer.

Case-Control Studies↗

Occupational and leisure-time physical activity and risk of colon cancer by subsite.

OBJECTIVE: Studies of physical activity and colon cancer risk by anatomic site have provided inconsistent results. METHODS: We analyzed data from a population-based case-control study conducted in Iowa involving 685 colon cancer cases and 2434 control subjects. RESULTS: Among those who reported recreational activity more than twice per week, a 30% risk reduction of colon cancer was observed for all sites with a 40% risk reduction for cancer of the right colon. Occupational physical activity was also associated with a reduced risk of colon cancer. The risk was the lowest for those with both high occupational and recreational physical activity (odds ratio, 0.5; 95% confidence interval, 0.3-0.8). CONCLUSIONS: Increased physical activity was inversely associated with colon cancer risk. The inverse associations were stronger for the right than for the left colon.

Adult↗

Does "clock" matter in prostate cancer?

The ancient adaptation of a 24-hour circadian clock has profound effect on our daily biochemical, physiologic, and behavioral processes, including the monitoring of sex hormone levels. Although the disruption of the circadian cycle has been implicated in the etiology of hormone-related female breast cancer, few studies have been undertaken to determine if a link exists in the development of the most common cancer type among men whose etiology remains largely unknown: hormone-related prostate cancer. Here, we hypothesize that both altered-lighted environments and genetic variations in genes responsible for maintaining circadian rhythms may result in deregulation of clock-associated biological processes, such as androgen expression, and consequently influence an individual's risk of prostate cancer. There is also a potential for the interaction of genetic variants and exposures, such as evening shift work. Confirmation of this hypothesis will add to our understanding of the role of the circadian clock in prostate tumorigenesis and further facilitate the development of novel risk and prognostic biomarkers for prostate cancer.

Androgens↗

A putative exonic splicing polymorphism in the BCL6 gene and the risk of non-Hodgkin lymphoma.

Recent studies have shown that the B-cell lymphoma 6 gene (BCL6) is an oncogene that contributes to lymphomagenesis. Exon 6 of BCL6 contains a common single nucleotide polymorphism (SNP) (-195 C>T; dbSNP ID: rs1056932) that alters a potential binding site for an exonic splicing enhancer. We used unconditional logistic regression models to examine the association between this SNP and the risk of non-Hodgkin lymphoma (NHL) in a population-based case-control study of women residing in Connecticut (461 case patients and 535 control subjects). The risk of NHL among women with the CC genotype was more than double that of women with the TT genotype (odds ratio [OR] = 2.2, 95% confidence interval [CI] = 1.5 to 3.3). Higher risks were observed for two NHL subtypes, namely B-cell chronic lymphatic leukemia/prolymphocytic leukemia/small lymphocytic lymphoma (OR = 3.5, 95% CI = 1.6 to 7.8) and T-cell lymphoma (OR = 5.2, 95% CI = 2.0 to 13.3). Our results support the hypothesis that a genetic variant that could alter mRNA transcripts of BCL6 may contribute to the etiology of NHL and suggest that this variant warrants further investigation.

Case-Control Studies↗

Breast cancer risk factors according to joint estrogen receptor and progesterone receptor status.

BACKGROUND: We investigated risk factor patterns for subtypes of breast cancer characterized by joint estrogen receptor (ER) and progesterone receptor (PR) status in a hospital-based case-control study. METHODS: ER and PR tumor status were determined immunohisotchemically. Risk factors of interest were entered into a multiple polychotomous logistic regression model simultaneously; odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. Using this model, cases in the four tumor subtypes (ER+PR+, ER-PR-, ER+PR-, ER-PR+) were compared simultaneously to controls. A Wald test for heterogeneity across the four subtypes was conducted, as well as a case-case comparison between the two most biologically disparate subtypes, ER+PR+ and ER-PR-. RESULTS: The receptor status distribution was as follows: 33% ER+PR+, 34% ER-PR-, 20% ER+PR-, and 13% ER-PR+. Among 317 cases and 401 controls, we found significant heterogeneity across the four tumor subtypes for older age at first full-term pregnancy (p=0.04) and post-menopausal status (p=0.04). For older age at first full-term pregnancy, an elevated risk was found for the ER+PR- subtype (OR=2.5; 95% CI: 1.2-5.1). For post-menopausal status, elevated risks were found for both the ER+PR+ (OR=2.4; 95% CI: 1.1-4.9) and ER+PR- (OR=7.2; 95% CI: 2.4-21.7) subtypes. From the case-case comparisons, we found that cases, who had consumed alcohol for more than 1 year were 3.4 times more likely to have ER+PR+ tumors than ER-PR- tumors (95% CI: 1.4-8.4). CONCLUSIONS: Certain breast cancer risk factors may vary by ER and PR status, and joint ER/PR status should be taken into account in future studies of risk factor estimates.

Adult↗

Polymorphisms in the DNA nucleotide excision repair genes and lung cancer risk in Xuan Wei, China.

The lung cancer mortality rate in Xuan Wei County is among the highest in China and has been attributed to exposure to indoor smoky coal emissions that contain very high levels of polycyclic aromatic hydrocarbons (PAHs). Nucleotide excision repair (NER) plays a key role in reversing DNA damage from exposure to environmental carcinogens, such as PAHs, that form bulky DNA adducts. We studied single nucleotide polymorphisms (SNPs) and their corresponding haplotypes in 6 genes (ERCC1, ERCC2/XPD, ERCC4/XPF, ERCC5/XPG, RAD23B and XPC) involved in NER in a population-based case-control study of lung cancer in Xuan Wei. A total of 122 incident primary lung cancer cases and 122 individually matched controls were enrolled. Three linked SNPs in ERCC2 were associated with lung cancer with similar ORs; e.g., persons with the Gln allele at codon 751 had a 60% reduction of lung cancer (OR = 0.40, 95% CI 0.18-0.89). Moreover, one haplotype in ERCC2 was associated with a decreased risk of lung cancer (OR = 0.40, 95% CI 0.19-0.85) compared to the most common haplotype. In addition, subjects with one or 2 copies of the Val allele at codon 249 of RAD23B had a 2-fold increased risk of lung cancer (OR = 1.91, 95% CI 1.12-3.24). In summary, our results suggest that genetic variants in genes involved in the NER pathway may play a role in lung cancer susceptibility in Xuan Wei. However, due to the small sample size, additional studies are needed to evaluate these associations within Xuan Wei and in other populations with substantial environmental exposure to PAHs.

Adult↗

Genotypes and haplotypes of the methyl-CpG-binding domain 2 modify breast cancer risk dependent upon menopausal status.

INTRODUCTION: MBD2, the gene encoding methyl-CpG-binding domain (MBD)2, is a major methylation related gene and functions as a transcriptional repressor that can specifically bind to the methylated regions of other genes. MBD2 may also mediate gene activation because of its potential DNA demethylase activity. The present case-control study investigated associations between two single nucleotide polymorphisms (SNPs) in the MBD2 gene and breast cancer risk. METHODS: DNA samples from 393 Caucasian patients with breast cancer (cases) and 436 matched control individuals, collected in a recently completed breast cancer case-control study conducted in Connecticut, were included in the study. Because no coding SNPs were found in the MBD2 gene, one SNP in the noncoding exon (rs1259938) and another in the intron 3 (rs609791) were genotyped. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to estimate cancer risk associated with the variant genotypes and the reconstructed haplotypes. RESULTS: The variant genotypes at both SNP loci were significantly associated with reduced risk among premenopausal women (OR = 0.41 for rs1259938; OR = 0.54 for rs609791). Further haplotype analyses showed that the two rare haplotypes (A-C and A-G) were significantly associated with reduced breast cancer risk (OR = 0.40, 95% CI = 0.20-0.83 for A-C; OR = 0.47, 95% CI = 0.26-0.84 for A-G) in premenopausal women. No significant associations were detected in the postmenopausal women and the whole population. CONCLUSION: Our results demonstrate a role for the MBD2 gene in breast carcinogenesis in premenopausal women. These findings suggest that genetic variations in methylation related genes may potentially serve as a biomarker in risk estimates for breast cancer.

Binding Sites↗

Alcohol consumption and risk of non-Hodgkin lymphoma: a pooled analysis.

BACKGROUND: Previous epidemiological studies of the relation between alcohol consumption and risk of non-Hodgkin lymphoma (NHL) have been inconsistent, probably because of small sample sizes of individual studies that result from stratification by NHL subtype and type of alcoholic beverage. We aimed to assess the role of alcohol consumption in NHL with sufficient sample size to analyse by both type of alcoholic beverage and disease subtype. METHODS: We obtained original data from nine case-control studies from the USA, UK, Sweden, and Italy in the International Lymphoma Epidemiology Consortium (InterLymph), yielding a pooled study population of 15 175 individuals (6492 cases and 8683 controls). We derived odds ratios (OR) and 95% CI from unconditional logistic regression models, controlling for study centre and other confounding factors. Heterogeneity between studies was assessed by comparison of results from joint fixed-effects logistic regression and two-stage random-effects logistic regression, and by calculation of Wald chi(2) statistics. FINDINGS: People who drank alcohol had a lower risk of NHL than did non-drinkers (OR 0.83 [95% CI 0.76-0.89]). Compared with non-drinkers, risk estimates were lower for current drinkers than for former drinkers (0.73 [0.64-0.84] vs 0.95 [0.80-1.14]), but risk did not decrease with increasing alcohol consumption. The protective effect of alcohol did not vary by beverage type, but did change with NHL subtype. The lowest risk estimates were recorded for Burkitt's lymphoma (0.51 [0.33-0.77]). INTERPRETATION: People who drink alcoholic beverages might have a lower risk of NHL than those who do not, and this risk might vary by NHL subtype. Further study designs are needed to determine whether confounding lifestyle factors or immunomodulatory effects of alcohol explain this association.

Adolescent↗

Occupation and risk of pancreatic cancer: a population-based case-control study in iowa.

OBJECTIVE: Previous epidemiological studies have inconsistently linked various occupations and industries to pancreatic cancer risk. METHODS: We analyzed data from a population-based case-control study conducted in Iowa involving 376 histologically confirmed incident pancreatic cancer cases and 2434 control subjects. RESULTS: A significantly increased risk was observed among men who worked in the following industries: chemical and allied products, transportation, and elementary and secondary schools. Increased risks also were observed in men who were employed as truck drivers; railroad brake, signal, and switch operators; purchasing agents and buyers; teachers; insurance agents; and retail supervisors. Among women, a significantly increased risk of pancreatic cancer was found for employment in furniture and home furnishing stores, and a borderline significantly increased risk among textile sewing machine operators and tenders. CONCLUSIONS: Working in several occupations and industries was associated with an increased risk of pancreatic cancer in this study, and these associations warrant further investigation.

Adult↗

A correlation study of organochlorine levels in serum, breast adipose tissue, and gluteal adipose tissue among breast cancer cases in India.

We used data from a breast cancer pilot study carried out in Kerala, India in 1997, for which organochlorine levels were measured in three biological media, blood serum, breast adipose tissue, and gluteal adipose tissue, of 37 fasting breast cancer cases (pretreatment). Our objective was to investigate the relationships between organochlorine concentrations in different biological media. Gas-liquid chromatography determined serum, breast adipose, and gluteal adipose tissue levels of dichlorodiphenyltricholorethane, dichlorodiphenyldichloroethane, beta-benzene hexachloride, and polychlorinated biphenyl (PCB) congeners, PCB-153 and PCB-180. Correlation plots were made and Spearman correlation coefficients (r) calculated for breast adipose tissue versus serum, gluteal adipose tissue versus serum, and breast adipose versus gluteal adipose tissue. We also examined paired ratios of all summary statistics. There were strong correlations among serum, breast adipose tissue, and gluteal adipose tissue concentrations for most organochlorines analyzed, one exception being gluteal versus serum for PCB-153. The correlations for all other comparisons ranged from r = 0.65 to 0.94. Serum (ng/g) versus adipose ratios approached 1:1 for most of the organochlorine pesticide comparisons and did not vary by summary statistic. To our knowledge, this is the first study to use three different media from fasting subjects and to comprehensively investigate the relationship between organochlorines measured across the three media for both organochlorine pesticides and PCBs. These data indicate that blood serum reflects the present body burden of a range of organochlorines to the same extent as adipose tissue, and they support the view that serum may be collected in lieu of adipose tissue to obtain similar information. However, such measurements are a combination of both recent exposures and past exposures, which have metabolized slowly and may still persist. Therefore, investigators should use caution when assigning a level as lifetime body burden.

Adipose Tissue↗