Marginal zinc intake reduces the protective effect of lactation on mammary gland carcinogenesis in a DMBA-induced tumor model in mice
Year: 2015
Type: article
Abstract: Breastfeeding can reduce breast cancer risk; however, unknown factors modify this protective effect. Zinc (Zn) modulates an array of cellular functions including oxidative stress, cell proliferation, motility and apoptosis. Marginal Zn intake is common in women and is associated with breast cancer. We reported that marginal Zn intake in mice leads to mammary gland hypoplasia and hallmarks of pre-neoplastic lesions. In the present study, we tested the hypothesis that marginal Zn intake confounds the protective effect of lactation on breast cancer. Nulliparous mice fed control (ZA, 30 mg Zn/kg) or a marginal Zn diet (ZD, 15 mg Zn/kg), were bred and offspring were weaned naturally. Post-involution, mice were gavaged with corn oil or 7,12-dimethylbenz(a)anthracene (DMBA, 1 mg/wk for 4 weeks) and tumor development was monitored. A ZD diet led to insufficient involution, increased fibrosis and oxidative stress. Following DMBA treatment, mice fed ZD had higher oxidative stress in mammary tissue that correlated with reduced levels of peroxiredoxin-1 and p53 and tended to have shorter tumor latency and greater incidence of non-palpable tumors. In summary, marginal Zn intake creates a toxic mammary gland microenvironment and abrogates the protective effect of lactation on carcinogenesis.
Source: Oncology Reports
DOI: 10.3892/or.2015.4508
Authors: ZEYNEP BOSTANCI, RONALD P. MACK, LAURA M. ENOMOTO, SAMINA ALAM, ASHLEY BROWN, CAROLA NEUMANN, DAVID I. SOYBEL, SHANNON L. KELLEHER
Institutions: Pennsylvania State University, University of Pittsburgh
Language: English
Topic: Trace Elements in Health
Subfield: Nutrition and Dietetics
Field: Nursing
Domain: Health Sciences
Open Access status: bronze
OpenAlex ID: W2215636520