Association between cadmium and breast cancer risk according to estrogen receptor and human epidermal growth factor receptor 2: epidemiological evidence

Abstract

The study aimed to examine the association between cadmium (Cd) and the risk of breast cancer according to estrogen receptor (ER) and human epidermal growth factor receptor 2 (HER2). A hospital-based case-control study was carried out in 585 cases and 1,170 controls. Information on possible risk factors was collected via a structured questionnaire. Urinary Cd was determined by atomic absorption spectrometry. The ER and HER2 levels in tumor tissue were analyzed by immunohistochemistry. Logistic regression was used to calculate odds ratios (ORs) and 95 % confidence intervals (CIs) for breast cancer by creatinine-adjusted urinary Cd. Women with greater creatinine-adjusted urine Cd (3rd quartile: 0.241-0.399 μg/g and 4th quartile: ≥ 0.4 μg/g) experienced 1.6 times higher risk of breast cancer compared with those having Cd concentration lower than 0.147 μg/g (1st quartile) [OR = 1.6, (95 % CI 1.19, 2.17) and OR = 1.62 (95 % CI 1.19, 2.21), respectively, P trend = 0.001] after adjustment for age and other confounders. Both ER+ and HER2- cases from the highest quartile of urine Cd exhibited approximately twice the breast cancer risk of those in the lowest quartile [OR = 1.9, (95 % CI 1.31, 2.74) and OR = 1.87, (95 % CI 1.33, 2.62), respectively, P trend <0.001) after adjustment for confounders. The data support cadmium as a risk factor for breast cancer, especially for both ER+ and HER2- cancer patients.

Residential Exposure to Estrogen Disrupting Hazardous Air Pollutants and Breast Cancer Risk

“…Higher cadmium concentrations were reported in breast tissue from breast cancer patients than from normal breast tissue. 19,20 Some epidemiologic studies have observed increased risk of overall breast cancer among women with higher urinary cadmium levels, 3,21-23 while one reported no association for dietary cadmium intake. 24 Several studies have reported elevated risks associated with cadmium that were confined to only ER+ tumors.…”

“…24 Several studies have reported elevated risks associated with cadmium that were confined to only ER+ tumors. 21,25 Julin et al, 4 however, reported increased risk for all breast cancer, ER+ tumors and ER- tumors associated with higher dietary cadmium exposure, though the ER- association was based on small numbers.…”

Associations of urinary cadmium with circulating sex hormone levels in pre- and postmenopausal Japanese women

“…Several epidemiological studies have shown that a high urinary cadmium level was associated with an increased risk of breast cancer (McElroy et al, 2006;Gallagher et al,2010;Nagata et al, 2013;Strumylaite et al, 2014;Wei et al, 2015). A recent meta-analysis of eight epidemiological studies reported a 1.66-fold risk increase (95% confidence interval 1.50, 3.34) for each 0.5 μg/g creatinine increase in the cadmium level, although large prospective studies are still needed for confirmation (Larsson et al, 2015).…”

Differential DNA methylation profile of key genes in malignant prostate epithelial cells transformed by inorganic arsenic or cadmium

“…Human exposure to Cd in the general population occurs primarily through consumption of contaminated food, although an additional source can be cigarette smoke (2012b). Cd is a human lung carcinogen and is possibly carcinogenic in the kidney, prostate, and breast (2012b; Strumylaite et al , 2014). Human exposure to environmental iAs occurs primarily by consumption of contaminated water (2012a).…”