Breast cancer risk factors: PCB congeners

Abstract

The chronic effects of polychlorinated biphenyls (PCBs) are a public health concern, and a potential relationship with breast cancer has been postulated. The purpose of this study was to examine the possible relationship between PCBs and breast cancer. All women (134) treated by excision biopsy because of breast lump at Reina Sofia University Hospital, Cordoba, Spain over a period of 10 months were included in our study. They were all administered a questionnaire by interview, calculation of body mass index, histopathological examination of excised mass and chemical estimation of PCB congener levels in breast fat. The collected samples were from 65 (48.5%) women with benign lesions and 69 (51.5%) with malignant lesions. The variables associated with malignant lesions on univariate analysis were age, lactation period, overweight, PCB n-28 and PCB n-52. On the multivariate analysis PCB n-28 was found to be the most important risk factor (OR 9.6, 95% CI 3.8-24.4). Other risk factors were identified as age, drinking alcohol, low parity and overweight. If these findings can be confirmed in a large study population, however, they may have important implications for breast cancer risk.

Breast cancer among Alaska Native women potentially exposed to environmental organochlorine chemicals

“…Increasing evidence suggests that PCBs may actually exert congener-specific effects that vary from estrogenic to anti-estrogenic (44)(45)(46), and future research should consider the effects of PCB congeners individually. A few studies have associated high levels of PCB congeners 183, 170, 180, and 28 with an increase in risk for breast cancer (2,(47)(48)(49) while congeners 153 and 156 were shown to have a protective effect in a New Haven, CT investigation (47). In our study all congener-specific PCB levels, like the total PCB level, were higher among control women.…”

Male breast tumors and oxidative DNA damage

“…Intriguingly, a similar interaction was observed in a previous study of breast cancer [25,26] also for prostate cancer [27]. This finding is compatible with smith et al in 2003 (28) who suggested that a high BMI might be associated with elevated levels of lipophilic aromatic compounds, such as polychlorinated biphenyls, aromatic and heterocyclic amines, and polycyclic aromatic hydrocarbons, stored in breast adipose tissue, leading to a continuous exposure to DNAdamaging agents. Deficient DNA repair may contribute to the accumulation of unrepaired damage in both lymphocytes and target tissue cells.…”

“…Deficient DNA repair may contribute to the accumulation of unrepaired damage in both lymphocytes and target tissue cells. This concept is supported by the evidence that higher levels of oxidative adducts were detected in breast cancer cases than in controls [28].…”

PCB-77 disturbs iron homeostasis through regulating hepcidin gene expression

“…PCBs, with slow rates of biotransformation in our biosphere, cause a variety of adverse effects on human health including reproductive, neurological and endocrine disorders (Loch-Caruso, 2002;Portigal et al, 2002;Schantz et al, 2003). Although a number of studies have investigated the toxicities of PCBs from various aspects, such as reproductive toxicity (Richthoff et al, 2003), inhibition of growth (COLE and PLAPP, 1974), immunotoxicity (Smialowicz et al, 1989;Tryphonas, 1995), hepatoxicity (Yoshimura et al, 1979), endocrine disruption effects (Birnbaum, 1994), neurotoxicity (Kodavanti and Tilson, 1996), enzyme induction (Burgin et al, 2001), and oncogenic effects (Lucena et al, 2001;Wolff et al, 2000;Zheng et al, 2000), the molecular mechanisms underlying these adverse effects are still elusive. Moreover, the potential influence of PCBs on iron metabolism has not been studied thus far.…”