Intratumoral Treatment with 5-Androstene-3ß, 17α-Diol Reduces Tumor Size and Lung Metastasis in a Triple-Negative Experimental Model of Breast Cancer.

Breast cancer treatment failure is related to low response rates, high costs, and long-term toxicities. Thus, it is necessary to find less toxic, cheaper, and more effective treatments. In situ administration ensures drug delivery to tumor cells and decreases systemic toxic effects. The androstene-3ß, 17α-diol (α-AED) reduces breast tumor cell proliferation and is an ideal candidate to treat mammary tumors. This study aims to identify the in vitro and in vivo effects of α-AED on a triple-negative mammary tumor model. An in vitro biphasic steroid effect was observed in mouse and human mammary tumor cells treated with α-AED. In this sense, cells treated with higher doses (100 and 200 µM) showed an antiproliferative effect. The α-AED administrated intratumorally reduced average tumor weight and increased the percentage of natural killer cells (NK), plasmatic, and plasmablast cells in mice tumors. Of note, VEGF levels in all α-AED-treated tumors was lower than in the control and vehicle groups. The tumor in situ increased response was reflected systemically by higher anti-4T1 IgG concentration in serum from α-AED-treated mice, but no other associated systemic changes were detected. The reduction in tumor size for the local injection of α-AED is associated with the anti-proliferative effect of this steroid, and the lower local levels of VEGF may be related to the imperceptible macroscopic metastasis in α-AED-treated mice. The above suggests that α-AED may be used in clinical studies to prove its efficacy as an alternative breast tumor treatment or in conjunction with already established therapies.

Association of Serum Levels of Plasticizers Compounds, Phthalates and Bisphenols, in Patients and Survivors of Breast Cancer: A Real Connection?

Phthalates and bisphenols are ubiquitous environmental pollutants with the ability to perturb different systems. Specifically, they can alter the endocrine system, and this is why they are also known as endocrine-disrupting compounds (EDCs). Interestingly, they are related to the development and progression of breast cancer (BC), but the threshold concentrations at which they trigger that are not well established. OBJECTIVES: The aim of this study was to compare the concentration measures of parent EDCs in three groups of women (without BC, with BC, and BC survivors) from two urban populations in Mexico, to establish a possible association between EDCs and this disease. We consider the measure of the parent compounds would reflect the individual's exposure. METHODS: The levels of di-ethyl-hexyl-phthalate (DEHP), butyl-benzyl-phthalate (BBP), di-n-butyl phthalate (DBP) and di-ethyl-phthalate (DEP), bisphenol A (BPA) and bisphenol S (BPS) were determined by gas chromatograph-mass spectrometry in 102 subjects, including 37 women without any pathological disease, 46 patients with BC and 19 women survivals of BC of Mexico and Toluca City. RESULTS: All phthalates were detected in 100% of women, two of them were significantly higher in patients with different BC subtypes in Mexico City. Differential increases were observed mainly in the serum concentration of phthalates in women with BC compared to women without disease between Mexico and Toluca City. In addition, when performing an analysis of the concentrations of phthalates by molecular type of BC, DEP and BBP were found mainly in aggressive and poorly differentiated types of BC. It should be noted that female BC survivors treated with anti-hormonal therapy showed lower levels of BBP than patients with BC. BPA and BPS were found in most samples from Mexico City. However, BPS was undetectable in women from Toluca City. DISCUSSION: The results of our study support the hypothesis of a positive association between exposure to phthalates and BC incidence.

The Endocrine Disruptor Compound Bisphenol-A (BPA) Regulates the Intra-Tumoral Immune Microenvironment and Increases Lung Metastasis in an Experimental Model of Breast Cancer.

Breast cancer (BC) metastasis represents the main physiopathology leading to poor prognosis and death. Bisphenol A (BPA) is a pollutant, classified as an endocrine-disrupting chemical compound with estrogenic properties, their exposure in the early stages of neonatal life leads to an increase in the size and weight of breast tumors and induces cellular changes in the tumoral immune microenvironment where cytokines play a key role. Thus, we used female BALB/c mice exposed neonatally to a single dose of BPA. Once mice reached sexual maturity, a mammary tumor was induced, injecting 4T1 cells in situ. After 25 days of injection, we evaluated endocrine alterations, cytokine expression, tissue alterations denoted by macro or micro-metastasis in the lung, and cell infiltration induced by metastasis. We found that BPA neonatal treatment did not show significant endocrine alterations. Noteworthy, BPA led to an augmented rate of metastasis to the lung associated with higher intratumoral expression of IL-1ß, IL-6, IFN-γ, TNF-α, and VEGF. Our data suggest that cytokines are key players in the induction of BC metastasis and that BPA (an environmental pollutant) should be considered as a risk factor in the clinical history of patients as a possible inductor of BC metastasis.

Environmental Pollution to Blame for Depressive Disorder?

Public concern has emerged about the effects of endocrine-disrupting compounds (EDCs) on neuropsychiatric disorders. Preclinical evidence suggests that exposure to EDCs is associated with the development of major depressive disorder (MDD) and could result in neural degeneration. The interaction of EDCs with hormonal receptors is the best-described mechanism of their biological activity. However, the dysregulation of the hypothalamic-pituitary-gonadal adrenal axis has been reported and linked to neurological disorders. At a worldwide level and in Mexico, the incidence of MDD has recently been increasing. Of note, in Mexico, there are no clinical associations on blood levels of EDCs and the incidence of the MDD. Methodology: Thus, we quantified for the first time the serum levels of parent compounds of two bisphenols and four phthalates in patients with MDD. The levels of di-ethyl-hexyl-phthalate (DEHP), butyl-benzyl-phthalate (BBP), di-n-butyl phthalate (DBP), and di-ethyl-phthalate (DEP), bisphenol A (BPA), and bisphenol S (BPS) in men and women with or without MDD were determined with a gas chromatograph-mass spectrometer. Results/conclusion: We found significant differences between concentrations of BBP between controls and patients with MDD. Interestingly, the serum levels of this compound have a dysmorphic behavior, being much higher in women (~500 ng/mL) than in men (≤10 ng/mL). We did not observe significant changes in the serum concentrations of the other phthalates or bisphenols tested, neither when comparing healthy and sick subjects nor when they were compared by gender. The results point out that BBP has a critical impact on the etiology of MDD disorder in Mexican patients, specifically in women.

Environmental pollutants: an immunoendocrine perspective on phthalates.

Phthalates are endocrine disrupting compounds (EDCs) used as plasticizers in a wide array of daily-use products, from flooring and automotive parts to medical devices and are even present in the children�s toys. Since these compounds are not covalently bound other molecules, they leach from these synthetic products, causing a high level of human exposure to them. EDCs exert several endocrine effects, most typically, reduced biosynthesis of the male hormone, testosterone and disturbances in estrogen, androgen, PPAR-gamma and AhR that control complex immunoendocrine regulatory networks. Besides impacting the developmental processes and long-term adverse effects, since cells of the immune system express endocrine receptors, and synthetize and respond to several hormones and other endocrine ligands, phthalates also cause dysregulation of immune system.

Potential Novel Risk Factor for Breast Cancer: Toxocara canis Infection Increases Tumor Size Due to Modulation of the Tumor Immune Microenvironment.

Worldwide, breast cancer is the most important type of cancer in women with regard to incidence and prevalence. Several risk factors interact to increase the probability of breast cancer development. Biological environmental contaminants such as infectious agents play a significant role in tumor development, and helminths have been recognized as cancer enhancers or inducers due to their ability to regulate the host immune response. Toxocara canis is a zoonotic and cosmopolite nematode with immuno-regulatory abilities. T. canis infection has been related to T helper type-2 cell (Th2 or type 2) and regulatory responses. Type 2 and regulatory immune responses may favor the development of comorbidities that are usually controlled or eliminated through a type 1 response such as cancer. The aim of this study was to determine whether T. canis infection alters mammary tumor growth through modulation of the immune response. Infected mice developed larger tumors. Tumor immune cell milieu analysis revealed that infection reduced the proportions of CD8+ lymphocytes and increased the proportions of F4/80+ macrophages and CD19+ B cells. These changes were accompanied by a type 2 local response represented by increased amounts of IL-4 and VEGF and a regulatory microenvironment associated with higher IL-10 levels. Thus, this study demonstrates that T. canis infection enhances tumor development and suggests that this is through modulation of the tumor immune microenvironment.

Bisphenol A induces protection through modulation of the immune response against the helminth parasite Taenia crassiceps.

AIMS: Industrial growth has increased the exposure to endocrine disruptor compounds (EDCs) in all organisms. Bisphenol A (BPA), an EDC, has been demonstrated to be involved in the susceptibility to parasite infections. However, few studies have analysed this connection in more depth. The aim of this study was to determine whether early BPA exposure in female mice affects the systemic immune response and the susceptibility to Taenia crassiceps infection. METHODS AND RESULTS: BALB/c mice were exposed to BPA at post-natal day 3. At 6 weeks of age, they were inoculated with T crassiceps larvae and, 2 weeks later, were euthanized. The number of parasites was quantified. By flow cytometry, in the spleen, the peripheral and mesenteric lymph nodes, the different innate and adaptive immune cell modulation was analysed, and RT-PCR cytokine expression was also evaluated. BPA induced a reduction of 40% in parasite load. BPA treatment modulated some lineages of the innate immune response and caused slight changes in cells belonging to the adaptive immune response. Additionally, BPA enhanced the type 2 cytokine profile. CONCLUSION: Neonatal BPA treatment in female mice affects not only the percentage of different immune cells but also their ex vivo cytokine gene expression, decreasing T crassiceps cysticercosis susceptibility.

Chronic exercise modulates the cellular immunity and its cannabinoid receptors expression.

The impact of performing exercise on the immune system presents contrasting effects on health when performed at different intensities. In addition, the consequences of performing chronic exercise have not been sufficiently studied in contrast to the effects of acute bouts of exercise. The porpoise of this work was to determine the effect that a popular exercise regimen (chronic/moderate/aerobic exercise) has on the proportion of different immune cell subsets, their function and if it affects the cannabinoid system with potentially functional implications on the immune system. A marked increase in several immune cell subsets and their expression of cannabinoid receptors was expected, as well as an enhanced proliferative and cytotoxic activity by total splenocytes in exercised animals. For this study male Wistar rats performed treadmill running 5 times a week for a period of 10 weeks, at moderate intensity. Our results showed a significant decrease in lymphocyte subpopulations (CD4+, Tγδ, and CD45 RA+ cells) and an increase in the cannabinoid receptors expression in those same cell. Although functional assays did not reveal any variation in total immunoglobulin production or NK cells cytotoxic activity, proliferative capability of total splenocytes increased in trained rats. Our results further support the notion that exercise affects the immunological system and extends the description of underlying mechanisms mediating such effects. Altogether, our results contribute to the understanding of the benefits of exercise on the practitioner´s general health.

Immune response to chronic Toxocara canis infection in a mice model.

AIMS: The zoonotic nematode Toxocara canis causes larva migrans syndrome that induces an immune response characterized by the production of antibodies and eosinophilia. A Th2 polarization has been associated with the infection, but there are still details of the cellular and humoral immune response that need to be described. Thus, the aim of this study was to describe the systemic host immune response to T canis chronic infection in a mouse model. METHODS AND RESULTS: BALB/c mice were inoculated once with 500 T canis embryonated eggs, per os. After 49 days, the amounts of larval found in brain and muscle tissues were statistically two and four times higher, respectively, than the amounts found in lung, liver, kidney or heart tissues. Splenic proportions of F4/80+ cells, as well as B, cytotoxic T and CD4+ Foxp3+ lymphocytes, were statistically higher (P ≤ .05, P ≤ .01, P ≤ .001 and P ≤ .001, respectively) as compared with control mice. In lymph nodes, some of these proportions changed, with the exception of F4/80+ cells. IgG1 levels in infected mice sera were increased. IL-4, IL-10 and VEGF levels were statistically higher in spleen (P ≤ .05, all) and sera (P ≤ .01, P ≤ .05 and P ≤ .05, respectively) in the infected mice. Also, in infected animals, IL-5 serum levels were increased (P ≤ .01). CONCLUSION: These results suggest that T canis chronic infection in BALB/c mice results in a type 2 response with an incipient regulatory response.

Cytotoxic and genotoxic effects of Benzo[ghi]perylene on the human bronchial cell line NL-20.

Benzo[ghi]perylene is the most abundant polycyclic aromatic hydrocarbon in the atmosphere of highly polluted cities with high altitudes like Mexico City. We evaluated the in vitro cytotoxic and genotoxic effects that Benzo[ghi]perylene could induce to the bronchial cell line NL-20 after 3 h of exposure. Furthermore, exposed cells were washed and maintained for 24 h without the treatment (recovery time), in order to evaluate a persistent damage to the cells. We found that at 3 h of exposure, 20% and 47% of the cells displayed cytoplasmic vesicles (p <0.05) and ɣH2AX foci in the nuclei (p <0.05), respectively. Furthermore, 27% of cells showed translocation of the factor inductor apoptosis into the nuclei (p <0.05) and an increase of proliferating cells was also observed (21%, p <0.05). The cells after recovery time continued displaying morphological changes and ɣH2AX foci, despite of the increased expression (> 2-times fold change) of some DNA repair genes (p <0.05) found before the recovery time. We also found that the cell nuclei contained Benzo[ghi]perylene after the exposure and it remains there after the recovery time (p <0.01). Therefore, hereby we report the cytotoxic and genotoxic effects that Benzo[ghi]perylene is capable to induce to NL-20 cells.

Breast Cancer Metastasis: Are Cytokines Important Players During Its Development and Progression?

In breast cancer, an uncontrolled cell proliferation leads to tumor formation and development of a multifactorial disease. Metastasis is a complex process that involves tumor spread to distant parts of the body from its original site. Metastatic dissemination represents the main physiopathology of cancer. Inter- and intracellular communication in all systems in vertebrates is mediated by cytokines, which are highly inducible, secretory proteins, produced not only by immune system cells, but also by endocrine and nervous system cells. It has become clear in recent years that cytokines, as well as their receptors are produced in the organisms under physiological and pathological conditions; recently, they have been closely related to breast cancer metastasis. The exact initiation process of breast cancer metastasis is unknown, although several hypotheses have emerged. In this study, we thoroughly reviewed the role of several cytokines in breast cancer metastasis. Data reviewed suggest that cytokines and growth factors are key players in the breast cancer metastasis induction. This knowledge must be considered with the aim to development of new therapeutic approaches to counter breast cancer metastasis.

A single neonatal administration of Bisphenol A induces higher tumour weight associated to changes in tumour microenvironment in the adulthood.

BPA is an oestrogenic endocrine disrupting chemical compound. Exposure to BPA in as early as pregnancy leads to lifelong effects. Since endocrine and immune systems interact in a bidirectional manner, endocrine disruption may cause permanent alterations of the immune system, affecting a future anti-tumoral response. Neonate (PND 3) female syngeneic BALB/c mice were exposed to a single dose of 250 µg/kg BPA. Once sexual maturity was reached, a mammary tumour was induced injecting 4T1 cells in situ, these cells are derived from a spontaneous adenocarcinoma in a BALB/c mouse and therefore allows for an immunocompetent recipient. After 25 days of injection, showing no major endocrine alterations, BPA-exposed mice developed larger tumours. Tumour leukocytic infiltrate analysis revealed a higher proportion of regulatory T lymphocytes in the BPA-exposed group. RT-PCR analysis of tumour samples showed a decreased expression of TNF-α and IFN-γ, as well as the M2 macrophage marker Fizz-1 in the BPA-exposed group. Flow cytometry analysis revealed differences in ERα expression by T lymphocytes, macrophages and NK cells, both associated to BPA exposure and tumour development. These findings show a new aspect whereby early life BPA exposure can contribute to breast cancer development and progression by modulating the anti-tumoral immune response.

The role of cytokines in breast cancer development and progression.

Cytokines are highly inducible, secretory proteins that mediate intercellular communication in the immune system. They are grouped into several protein families that are referred to as tumor necrosis factors, interleukins, interferons, and colony-stimulating factors. In recent years, it has become clear that some of these proteins as well as their receptors are produced in the organisms under physiological and pathological conditions. The exact initiation process of breast cancer is unknown, although several hypotheses have emerged. Inflammation has been proposed as an important player in tumor initiation, promotion, angiogenesis, and metastasis, all phenomena in which cytokines are prominent players. The data here suggest that cytokines play an important role in the regulation of both induction and protection in breast cancer. This knowledge could be fundamental for the proposal of new therapeutic approaches to particularly breast cancer and other cancer-related disorders.