Occupational Exposure to Pesticides Affects Pivotal Immunologic Anti-Tumor Responses in Breast Cancer Women from the Intermediate Risk of Recurrence and Death.

Breast cancer risk stratification is a strategy based using on clinical parameters to predict patients' risk of recurrence or death, categorized as low, intermediate, or high risk. Both low and high risk are based on well-defined clinical parameters. However, the intermediate risk depends on more malleable parameters. It means an increased possibility for either suboptimal treatment, leading to disease recurrence, or systemic damage due to drug overload toxicity. Therefore, identifying new factors that help to characterize better the intermediate-risk stratification, such as environmental exposures, is necessary. For this purpose, we evaluated the impact of occupational exposure to pesticides on the systemic profile of cytokines (IL-12, IL-4, IL-17A, and TNF-α) and oxidative stress (hydroperoxides, total antioxidants, and nitric oxide metabolites), as well as TGF-ß1, CTLA-4, CD8, and CD4 expression, investigated in tumor cells. Occupational exposure to pesticides decreased the levels of IL-12 and significantly increased the expression of TGF-ß1 and CTLA-4 in the immune infiltrate. Nevertheless, we observed a decrease in CTLA-4 in tumor samples and CD8 in infiltrating cells of intermediate overweight or obese patients with at least one metastatic lymph node at the diagnosis. These findings indicate that occupational exposure to pesticides changes the molecular behavior of disease and should be considered for intermediate-risk stratification assessment in breast cancer patients.

Clinical implications of lipid peroxides levels in plasma and tumor tissue in breast cancer patients.

Oxidative stress can promote the oxidation of lipoproteins and polyunsaturated fatty acids present in cell membranes; an event known as lipid peroxidation (LPO). LPO has been associated with carcinogenesis and cancer progression, however, its meaning concerning the clinicopathological aspects of human breast cancer is not clear. This study investigated LPO profiles in tumor and plasma samples from breast cancer patients (n = 140) considering their clinicopathological features (age at diagnosis, menopausal status, body mass index, tumor histological grade, tumor size, ki-67 proliferation index, presence of metastasis, chemotherapy response, the molecular subtype of cancer and overall survival status). LPO levels were estimated by tert-butyl hydroperoxide-initiated chemiluminescence. High LPO levels were found regarding poor prognosis parameters as young age at diagnosis (p = 0.006 in tissue), premenopausal patients (p = 0.012 in tissue), high-grade tumors (p = 0.010 in tissue and p = 0.002 in plasma), metastatic disease (p = 0.046 in tissue), chemoresistant tumors (p = 0.041 in tissue), disease relapse (p = 0.018 in tissue and p = 0.009 in plasma) and overall survival status (p = 0.001 in plasma). Our findings point out the clinical meaning of LPO and highlight it as an oxidative stress event linked to poor prognosis and disease aggressiveness in breast cancer patients.

Anti-neutrophil antibodies (anti-MPO-ANCAs) are associated with poor prognosis in breast cancer patients.

Anti-neutrophil antibodies are capable of activating neutrophils in sterile environments, releasing extracellular traps containing myeloperoxidase (MPO) and anti-MPO antibodies (MPO-ANCAs or anti-MPO-ANCAs), which have been implicated in the pathogenesis of several diseases. The present study evaluated systemic and tumor tissue levels of anti-MPO-ANCAs breast cancer patients, and its relation to clinicopathological characteristics. Anti-MPO-ANCAs were measured in serum and tissue samples of 150 patients by enzyme-linked immunoassay. Samples were pooled according to clinicopathological characteristics of patients. Higher anti-MPO-ANCAs levels were detected in groups presenting negative clinicopathological characteristics, such as high histological grade tumors and risk factors such as body mass index, menopausal status and early onset at diagnosis. The present data highlights anti-MPO-ANCAs as associated to poor prognosis in breast cancer, a role beyond its actually discussed role in autoimmunity and vasculitis.