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Well-defined physiological functions of estrogens are mediated via nuclear estrogen receptors α (ESR1) and β (ESR2). With regard to hematological malignancies, expression of ESR2 has been found in both B and T cell lymphomas. In addition to endogenous estrogens or selective ESR2 agonists, ESR2 signaling may be affected by both environmental synthetic estrogen-mimicking compounds and dietary phytoestrogens. In the present study, we demonstrate that oral exposure with either the synthetic compound bisphenol A (BPA) or the dietary phytoestrogen genistein reduced the growth of grafted murine T cell (EG7) and human B cell (Granta-519 mantle cell) lymphomas which both express ESR2. Suppression of lymphoma growth was due to reduced proliferation (BPA and genistein) and induction of apoptosis (genistein). Inhibition of lymphoma growth was seen at a BPA dose of 50 µg/kg body weight (BW)/day considered to be safe human exposure dose or a genistein dose of 1 mg/kg BW/day orally, which is reached in soy-rich diets. Thus, our study indicates that the environmental xenoestrogens BPA and genistein have anti-proliferative effects on ESR2-expressing lymphomas. Our data suggest that phytoestrogens may be considered as a dietary supplement for lymphoma patients and possibly for prevention of lymphoid malignancies.

Acromegaly is a systemic disease associated with increased morbidity and mortality. Most of these comorbidities can be prevented or delayed with adequate disease treatment. Although three modalities of treatment (surgery, medical treatment, and radiotherapy) are available and new drugs were approved in the last decades, there are still some patients that maintain disease activity despite treatment. Therefore, there is a need for novel therapies for acromegaly and for that purpose new formulations of currently used drugs and also new drugs are currently under study. In this review, we summarize the novel therapies for acromegaly.

Puberty marks a transition period, which leads to the attainment of adult sexual maturity. Timing of puberty is a strongly heritable trait. However, large genetic association studies can only explain a fraction of the observed variability and striking secular trends suggest that lifestyle and/or environmental factors are important. Using liquid-chromatography tandem-mass-spectrometry, we measured endocrine-disrupting chemicals (EDCs; triclosan, bisphenol A, benzophenone-3, 2,4-dichlorophenol, 11 metabolites from 5 phthalates) in longitudinal urine samples obtained biannually from peri-pubertal children included in the COPENHAGEN puberty cohort. EDC levels were associated with blood DNA methylation profiles from 31 boys and 20 girls measured both pre- and post-pubertally. We found little evidence of single methylation sites that on their own showed association with urinary excretion levels of EDCs obtained either the same-day or measured as the yearly mean of dichotomized EDC levels. In contrast, methylation of several promoter regions was found to be associated with two or more EDCs, overlap with known gene–chemical interactions, and form a core network with genes known to be important for puberty. Furthermore, children with the highest yearly mean of dichotomized urinary phthalate metabolite levels were associated with higher promoter methylation of the thyroid hormone receptor interactor 6 gene (TRIP6), which again was mirrored by lower circulating TRIP6 protein levels. In general, the mean TRIP6 promoter methylation was mirrored by circulating TRIP6 protein levels. Our results provide a potential molecular mode of action of how exposure to environmental chemicals may modify pubertal development.

Bisphenol A (BPA) is the most common monomer in polycarbonate plastics and an endocrine disruptor. Though some effects of BPA on thyroid hormone (TH) synthesis and action have been described, the impact of this compound on thyroid H₂O₂ generation remains elusive. H₂O₂ is a reactive oxygen species (ROS), which could have deleterious effect on thyrocytes if in excess. Therefore, herein we aimed at evaluating the effect of BPA exposition both in vivo and in vitro on H₂O₂ generation in thyrocytes, besides other essential steps for TH synthesis. Female Wistar rats were treated with vehicle (control) or BPA 40 mg/kg BW for 15 days, by gavage. We then evaluated thyroid iodide uptake, mediated by sodium-iodide symporter (NIS), thyroperoxidase (TPO) and dual oxidase (DOUX) activities (H₂O₂ generation). Hydrogen peroxide generation was increased, while iodide uptake and TPO activity were reduced by BPA exposition. We have also incubated the rat thyroid cell line PCCL3 with 10⁻⁹ M BPA and evaluated Nis and Duox mRNA levels, besides H₂O₂ generation. Similar to that found in vivo, BPA treatment also led to increased H₂O₂ generation in PCCL3. Nis mRNA levels were reduced and Duox2 mRNA levels were increased in BPA-exposed cells. To evaluate the importance of oxidative stress on BPA-induced Nis reduction, PCCL3 was treated with BPA in association to N-acetylcysteine, an antioxidant, which reversed the effect of BPA on Nis. Our data suggest that BPA increases ROS production in thyrocytes, what could lead to oxidative damage thus possibly predisposing to thyroid disease.

In patients with type 2 diabetes mellitus (T2DM), the intestinal flora is out of balance and accompanied by leaky gut. The flora is characterized by an increase in mucus-degrading bacteria and a decrease in fiber-degrading bacteria. Short-chain fatty acids (SCFAs), as the major fiber-degrading bacteria fermentation, not only ameliorate the leaky gut, but also activate GPR43 to increase the mass of functional pancreatic β-cells and exert anti-inflammation effect. At present, the gut microbiota is considered as the potential target for anti-diabetes drugs, and how to reverse the imbalance of gut microbiota has become a therapeutic strategy for T2DM. This review briefly summarizes the drugs or compounds that have direct or potential therapeutic effects on T2DM by modulating the gut microbiota, including biguanides, isoquinoline alkaloids, stilbene and C7N-aminocyclic alcohols.

Preclinical trials of medullary thyroid cancer (MTC) therapeutics require both in vitro and in vivo analyses. Human tumour xenografted rodent models, which are considered the ‘gold standard’ to study and validate the efficacy and toxicity of lead compounds before translation to clinical trials, are very expensive, subject to organismal variability and ethical controversies. The avian chorioallantoic membrane (CAM) assay provides an alternative versatile, cost-effective and ethically less objectionable short-term, in vivo model for reliable screening of drugs. In this work, we grafted two MTC cell lines and patient-derived MTC tumour samples onto the avian CAM and characterised the resulted tumours histologically and immunohistochemically. Our findings provide the evidence that the CAM assay is a suitable model for studying the pathophysiology of MTC and can even be used as in vivo system for drug testing.

Adrenocortical carcinomas (ACCs) are rare tumors with scant treatment options for which new treatments are required. The mTOR pathway mediates the intracellular signals of several growth factors, including the insulin-like growth factors (IGFs), and therefore represents a potential attractive pathway for the treatment of several malignancies including ACCs. Several mTOR inhibitors, including sirolimus, temsirolimus and everolimus, have been clinically developed. This review summarizes the results of the studies evaluating the expression of the mTOR pathway components in ACCs, the effects of the mTOR inhibitors alone or in combination with other drugs in preclinical models of ACCs and the early experience with the use of these compounds in the clinical setting. The mTOR pathway seems a potential target for treatment of patients with ACC, but further investigation is still required to define the potential role of mTOR inhibitors alone or in combination with other drugs in the treatment of ACC patients.