Association of breast adipose tissue levels of polychlorinated biphenyls and breast cancer development in women from Chaoshan, China

Abstract

Polychlorinated biphenyls (PCBs) are implied to be potential risk factors for breast cancer in wildlife and in in vivo and in vitro studies. Epidemiological studies revealed some individual or groups of PCB congeners associated with breast cancer risk, but consistent conclusions are scarce. This study aimed to explore the association between PCB exposure and breast cancer development. Breast adipose tissues were collected, and seven PCB congeners were analyzed by gas chromatography-mass spectrometry (GC-MS). Demographic characteristics, basic clinical data, and pathological diagnosis information were obtained from medical records. The differences in PCB exposure levels among different groups and indices were compared, and the correlation among PCB congeners was evaluated. The order of congener profile by molar concentration was PCB-153 > PCB-138 > PCB-180 > PCB-118 > PCB-101 > PCB-52 > PCB-28. ∑PCB level differed by occupation and residence and was significantly higher at 55-59-year-old group than at the other age groups. ∑PCB level was higher in postmenopausal than in premenopausal women. Decreasing ∑PCB levels were related with increasing parity among women with progesterone receptor (PR)-positive breast tumors. With increased clinical stage, the ∑PCB level increased significantly. ∑PCB level did not differ by tumor-node-metastasis classification and PR or human epidermal growth factor receptor 2 (HER2) expression but did differ by estrogen receptor (ER) expression (P = 0.04) without a regularly increasing trend in breast adipose tissue. These results suggest a potential association between PCB exposure and breast cancer development. Further in vitro and in vivo studies are needed to confirm these findings and explain the underlying mechanisms. Graphical Abstract Total PCBs level among different clinical stages in breast cancer patients.

Organochlorine pesticide residues in human breast tissue and their relationships with clinical and pathological characteristics of breast cancer

“…Breast tumors with an ER+/HER2‐ phenotype are characterized by favorable clinical features such as lower histological grade, a smaller size at diagnosis, and negative lymph node status compared to other tumor types . Some recent studies have observed inverse correlations between organochlorine residues and markers of primary tumor aggressiveness and breast cancer mortality . In this study, we also observed a significant inverse relationship between pesticide levels in breast adipose tissue and pathological markers of prognosis.…”

Breast and prostate glands affected by environmental substances (Review)

“…Some notable results about non-monotonic and ER expression were obtained in a study conducted on Chinese women (28). Exposure to PCBs was measured in breast adipose tissues of 230 women undergoing a biopsy, lumpectomy or mastectomy: First, PCB153 was detected with the highest molar concentrations compared with the other six congeners that were evaluated; second, postmenopausal women presented the highest levels of PCBs compared with premenopausal women; and third, PCB levels were different from ER expression, showing a non-linear change, presumably due to its non-monotonic response curve, the same as E2 behavior, affecting the ER transcription (56). Similarly, a population-based study suggested that DDE increased breast cancer risk at lower doses (25).…”

“…PCBs comprise highly halogenated congeners, providing lipophilicity, which allows bioaccumulation in adipose tissue (24,56). Therefore, it is suggested that this bioaccumulation has a causal association with breast cancer risk.…”

“…Monotonic and non-monotonic response. Hormones, exogenous estrogens and oral contraceptives are known factors that increase breast cancer risk (56). It may be hypothesized that high doses of these factors may increase the risk of breast or other types of cancer, but this is not always the case for EDCs.…”

The Undervalued Effects of Polychlorinated Biphenyl Exposure on Breast Cancer

“…In contrast, some PCB congeners were reported to positively associated with ER or PR expression. 19,88,89 Several explanations have been suggested regarding these significant findings. One study described lower levels of estrogens in ER þ cases and higher levels in ER À cases, which was explained by the ER þ tumors' growth-dependent uptake of estrogen.…”