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Breast cancer research heavily relies on diverse model systems to comprehend disease progression, develop novel diagnostics, and evaluate new therapeutic strategies. This review offers a comprehensive overview of mammary cancer models, covering both ex vivo and in vivo approaches. We delve into established techniques, such as cell culture and explore cutting-edge advancements, like tumor-on-a-chip and bioprinting. The in vivo section encompasses spontaneous, induced, and transplanted models, genetically engineered models, chick chorioallantoic membrane assays, and the burgeoning field of in silico models. Additionally, this article briefly highlights the key discoveries made using these models, significantly enhancing our understanding of breast cancer. In essence, this article serves as a comprehensive compass, charting the trajectory of mammary cancer modeling from its early beginnings to the promising vistas of tomorrow. [ABSTRACT FROM AUTHOR]

Background and Aim: Papillomaviruses (PVs) infections have been documented in numerous animal species across different regions worldwide. They often exert significant impacts on animal health and livestock production. Scientists have studied natural products for over half a century due to their diverse chemical composition, acknowledging their value in fighting cancer. Acorns (Quercus ilex) are believed to have several unexplored pharmacological properties. This study aimed to evaluate the in vivo safety and cancer chemopreventive activity of an infusion extract of Q. ilex in a transgenic mouse model of human PV (HPV)-16, which developed squamous cell carcinomas through a multistep process driven by HPV16 oncogenes. Materials and Methods: Q. ilex extract was prepared by heating in water at 90°C and then characterized by mass spectrometry. Phenolic compounds from this extract were administered in drinking water to female mice in three different concentrations (0.03, 0.06, and 0.09 g/mL) over a period of 28 consecutive days. Six groups (n = 6) were formed for this study: group 1 (G1, wildtype [WT], water), group 2 (G2, HPV, water), group 3 (G3, WT, 0.09 g/mL), group 4 (G4, HPV, 0.03 g/mL), group 5 (G5, HPV, 0.06 g/ mL), and group 6 (G6, HPV, 0.09 g/mL). Throughout the experiment, humane endpoints, body weight, food intake, and water consumption were recorded weekly. Following the experimental period, all mice were sacrificed, and blood, internal organs, and skin samples were collected. Blood was used to measure glucose and microhematocrit and later biochemical parameters, such as creatinine, urea, albumin, alanine aminotransferase, and total proteins. Histological analysis was performed on skin and organ samples. Results: The administration of Q. ilex extract resulted in a statistically significant increase in relative organ weight among HPV transgenic animals, indicating adaptive biological response to the tested concentrations. Moreover, a reduction in characteristic skin lesions was observed in animals treated with the 0.06 and 0.09 g/mL extract. Conclusion: These results provide a favorable chemopreventive profile for Q. ilex extract at concentrations of 0.06 and 0.09 g/mL. This study highlights the potential of Q. ilex extract as a safe and effective therapeutic strategy against HPV16-associated lesions in transgenic mouse models. The limitation of our study was the durability of transgenic animals. As a more sensitive species, we must always be careful with the durability of the test. We intend to study concentrations of 0.06 and 0.09 g/mL for longer to further investigate their possible effects. [ABSTRACT FROM AUTHOR]

Echocardiography is a reliable and non-invasive method for assessing cardiac structure and function in both clinical and experimental settings, offering valuable insights into disease progression and treatment efficacy. The successful application of echocardiography in murine models of disease has enabled the evaluation of disease severity, drug testing, and continuous monitoring of cardiac function in these animals. However, there is insufficient standardization of echocardiographic measurements for smaller animals. This article aims to address this gap by providing a guide and practical tips for the appropriate acquisition and analysis of echocardiographic parameters in adult rats, which may also be applicable in other small rodents used for scientific purposes, like mice. With advancements in technology, such as ultrahigh-frequency ultrasonic transducers, echocardiography has become a highly sophisticated imaging modality, offering high temporal and spatial resolution imaging, thereby allowing for real-time monitoring of cardiac function throughout the lifespan of small animals. Moreover, it allows the assessment of cardiac complications associated with aging, cancer, diabetes, and obesity, as well as the monitoring of cardiotoxicity induced by therapeutic interventions in preclinical models, providing important information for translational research. Finally, this paper discusses the future directions of cardiac preclinical ultrasound, highlighting the need for continued standardization to advance research and improve clinical outcomes to facilitate early disease detection and the translation of findings into clinical practice. [ABSTRACT FROM AUTHOR]

Chronic inflammation plays a crucial role in carcinogenesis. High levels of serum prostaglandin E2 and tissue overexpression of cyclooxygenase-2 (COX-2) have been described in breast, urinary, colorectal, prostate, and lung cancers as being involved in tumor initiation, promotion, progression, angiogenesis, and immunosuppression. Nonsteroidal anti-inflammatory drugs (NSAIDs) are prescribed for several medical conditions to not only decrease pain and fever but also reduce inflammation by inhibiting COX and its product synthesis. To date, significant efforts have been made to better understand and clarify the interplay between cancer development, inflammation, and NSAIDs with a view toward addressing their potential for cancer management. This review provides readers with an overview of the potential use of NSAIDs and selective COX-2 inhibitors for breast cancer treatment, highlighting pre-clinical in vitro and in vivo studies employed to evaluate the efficacy of NSAIDs and their use in combination with other antineoplastic drugs. [ABSTRACT FROM AUTHOR]

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The salivary glands play a central role in the secretion of saliva, whose composition and volume affect oral and overall health. A lesser-explored dimension encompasses the possible changes in salivary gland proteomes in response to fluctuations in sex hormone levels. This study aimed to examine the effects of chronic exposure to testosterone on salivary gland remodeling, particularly focusing on proteomic adaptations. Therefore, male Wistar rats were implanted with subcutaneous testosterone-releasing devices at 14 weeks of age. Their submandibular glands were histologically and molecularly analyzed 47 weeks later. The results underscored a significant increase in gland mass after testosterone exposure, further supported by histologic evidence of granular duct enlargement. Despite increased circulating sex hormones, there was no detectable shift in the tissue levels of estrogen alpha and androgen receptors. GeLC-MS/MS and subsequent bioinformatics identified 308 proteins in the submandibular glands, 12 of which were modulated by testosterone. Of note was the pronounced upregulation of Klk3 and the downregulation of Klk6 and Klk7 after testosterone exposure. Protein–protein interaction analysis with the androgen receptor suggests that Klk3 is a potential target of androgenic signaling, paralleling previous findings in the prostate. This exploratory analysis sheds light on the response of salivary glands to testosterone exposure, providing proteome-level insights into the associated weight and histological changes. [ABSTRACT FROM AUTHOR]

Background: Teratomas are rare types of germ cell neoplasms composed of various differentiated or undifferentiated tissues. Case Description: A 25-week-old female control FVB /n mouse in a 4-week toxicity study presented abdominal distension and poor body condition. It was euthanized, and the necropsy examination revealed a large mass connected to the tip of the right uterine horn, occupying the entire abdominal cavity. Microscopically, this mass showed areas of epidermal differentiation, with laminated keratin and sebaceous glands, differentiation into respiratory and digestive epithelium, cartilage, bone, and extensive areas of differentiation into the nervous tissue, being classified as an ovarian teratoma. Conclusion: As far as authors know, the occurrence of ovarian teratomas in the FVB/n mouse strain has never been previously described. [ABSTRACT FROM AUTHOR]

The analysis of metals in different tissues of raptors has been an important tool for assessing metal pollution. Several studies using a range of sentinel raptor species have been carried out in Portugal and Spain since the 1980s to identify the adverse effects in the animals themselves and on their populations, to identify the contamination of the food chain, to determine the levels of environmental contamination and to estimate human health risks. The aim of this work is to provide synthesized information of the studies carried out in Portugal and Spain in the direct biomonitoring of metals and metalloids using raptors, through a systematic search of the published literature. The information is summarized taking into account specific issues, such as monitored raptor species, sampling periods, monitored areas, type of samples, analytical techniques used in the determination of the metals and metalloids, the analysed metals and metalloids, and overall analysis of the concentrations obtained. There is a striking difference between the number of studies performed in Portugal and Spain, and most of them have been carried out in Spain. The eagle owl, black kite, and common buzzard were the species from which the greatest number of individuals have been analysed. Among the most analyzed biological samples, the blood and liver samples were used to measure the concentrations of all studied metals, while bone was mainly collected to evaluate chronic exposure to lead and feathers to evaluate exposure to mercury during feather growth. Atomic absorption spectrometry has been the most frequently performed technique to determine the majority of metals and arsenic. In general, the concentrations of metals detected in raptor samples from Portugal and Spain are low and insufficient to produce toxic side effects. Only lead, in certain cases, can be related with toxic side effects. However, particular attention should be given to mercury due to its high toxicity, its transport from an aquatic environment to the adjacent terrestrial food web, and because the mercury toxicity threshold has yet to be established for raptors. This work confirms the need for further biomonitoring studies of metals with raptors, especially in Portugal; the establishing of national programs to conduct long-term studies; and creating a network between Portugal and Spain to study environmental contamination using raptors. Key words: biomonitoring, environmental contamination, metals, raptors, Portugal, Spain. L'analyse des metaux dans differents tissus de rapaces a constitue un moyen important pour evaluer la pollution par les metaux. Plusieurs etudes faisant appel a un ensemble d'especes sentinelles ont ete conduites au Portugal et en Espagne depuis les annees 1980, afin d'identifier les effets adverses chez les animaux eux-memes et sur leurs populations, d'identifier la contamination de la chaine alimentaire, de determiner le degre de contamination environnemental, ainsi que d'estimer les risques pour la sante humaine. Le but du travail effectue vise a produire une information synthetisee des etudes conduites au Portugal et en Espagne avec le suivi direct des metaux et des metalloides en utilisant des rapaces, en conduisant une recherche systematique dans la litterature publiee. On resume cette information en tenant compte de questions specifiques comme les especes suivies, les periodes d'echantillonnage, les surfaces utilisees, les types d'echantillons, les techniques analytiques utilisees dans la determination des metaux et des metalloides, les metaux et metalloides analyses et les analyses globales obtenues. On observe une nette difference entre le nombre d'etudes conduites au Portugal et en Espagne, la plupart d'entre elles ayant ete menees en Espagne. Le hibou grand-duc, le milan noir, et le busard commun constituent les especes pour lesquelles le plus grand nombre d'individus ont ete analyses. Parmi les echantillons biologiques les plus analyses, les echantillons de sang et de foie ont servi a mesurer les teneurs de tous les metaux etudies, alors que les os ont ete recoltes surtout pour evaluer les expositions chroniques au plomb et les plumes pour evaluer les expositions au mercure au cours de la croissance des plumes. La spectroscopie par absorption atomique represente la technique la plus frequemment appliquee pour determiner la majorite des metaux et l'arsenic. En general, les teneurs en metaux detectees dans les echantillons de rapaces du Portugal et de l'Espagne sont faibles et insuffisantes pour produire des effets toxiques secondaires. Seul le plomb, dans certains cas, montre une relation avec des effets toxiques secondaires. Cependant, on devrait donner une attention speciale au mercure compte tenu de sa forte toxicite, de son transport du milieu aquatique vers la chaine alimentaire terrestre voisine et parce que le seuil de toxicite du mercure reste a etablir pour les rapaces. Ce travail confirme le besoin de conduire d'autres etudes de suivi des metaux en utilisant les rapaces, surtout au Portugal avec la mise en place de programmes nationaux pour conduire des etudes a long terme et la creation d'un reseau entre le Portugal et l'Espagne afin d'etudier la contamination environnementale en utilisant des rapaces. [Traduit par la Redaction] Mots-cles: suivi, contamination environnementale, metaux, rapaces, Portugal, Espagne., 1. Introduction Metals are natural constituents of all ecosystems and are present at low concentrations in soils, plants, and living organisms. Their distribution in the environment results from natural processes [...]

Cancer is one of the most important public health problems worldwide. Despite the great contribution of in-vitro studies for biomedical research, animals are essential to study diseases' biopathology and diagnosis, and searching for new preventive and therapeutic strategies. Breast cancer is currently the most common cancer globally, accounting for 12.5% of all new annual cancer cases worldwide. Although the rat model of mammary cancer chemically-induced is widely used to study this disease, there is a lack of standardization in procedures for cancer induction, sample collection, and analysis. Therefore, it is important to provide a practical guide for researchers aiming to work with this model to make the analysis of results more uniform. Thus, in this review, we provide the researchers with a detailed step-by-step guide to implement a rat model of mammary cancer, based on our wide experience in this field, to obtain the best results, maximum throughput of each experiment, and easy comparison among researches. [ABSTRACT FROM AUTHOR]

Objective(s): The present work intended to clearly define the most adequate humane endpoints in an experimental assay of mammary carcinogenesis in rats. Materials and Methods: Animals were observed twice a day; all parameters were registered once a week and the euthanasia endpoints were established in order to monitor the animal welfare/distress during an experimental assay of chemically-induced mammary carcinogenesis in female rats. Results: Fourteen animals developed at least one mammary tumor with a diameter >35 mm. No animals exhibited alterations in the remaining parameters that implied their early sacrifice. Statistically significant changes were not observed in the quantitative parameters like the hematocrit and urine specific gravity among groups, not being valuable for the assessment of the health status of animals included in an assay of mammary carcinogenesis for 18 weeks. The remaining humane endpoints seemed to be helpful to monitor the animals' health status. Conclusion: The alteration in only one humane endpoint (mammary tumor dimensions) does not imply the animals' sacrifice; the endpoints should be evaluated in conjunction, in order to define the most adequate time in which the animals should be sacrificed. [ABSTRACT FROM AUTHOR]

The salivary glands play a central role in the secretion of saliva, whose composition and volume affect oral and overall health. A lesser-explored dimension encompasses the possible changes in salivary gland proteomes in response to fluctuations in sex hormone levels. This study aimed to examine the effects of chronic exposure to testosterone on salivary gland remodeling, particularly focusing on proteomic adaptations. Therefore, male Wistar rats were implanted with subcutaneous testosterone-releasing devices at 14 weeks of age. Their submandibular glands were histologically and molecularly analyzed 47 weeks later. The results underscored a significant increase in gland mass after testosterone exposure, further supported by histologic evidence of granular duct enlargement. Despite increased circulating sex hormones, there was no detectable shift in the tissue levels of estrogen alpha and androgen receptors. GeLC-MS/MS and subsequent bioinformatics identified 308 proteins in the submandibular glands, 12 of which were modulated by testosterone. Of note was the pronounced upregulation of Klk3 and the downregulation of Klk6 and Klk7 after testosterone exposure. Protein-protein interaction analysis with the androgen receptor suggests that Klk3 is a potential target of androgenic signaling, paralleling previous findings in the prostate. This exploratory analysis sheds light on the response of salivary glands to testosterone exposure, providing proteome-level insights into the associated weight and histological changes.

Background/aim: Intense pulsed light (IPL) has been extensively applied in the field of dermatology and aesthetics; however, the long-term consequences of its use are poorly unknown, and to the best of our knowledge there is no study on the effect of IPL in neoplastic lesions. In order to better understand the molecular mechanisms underlying IPL application in the skin, we used an animal model of carcinogenesis obtained by chemical induction with 12-dimethylbenz(a)anthracene (DMBA) and 12-O-tetradecanoylphorbol-13-acetate (TPA)., Materials and Methods: Institute of Cancer Research (ICR) mice were administered DMBA and/or TPA and treated with IPL. Skin was evaluated by histopathology and 2DE-blot-MS/MS analysis., Results: Our data evidenced an inflammatory response and a metabolic remodeling of skin towards a glycolytic phenotype after chronic exposure to IPL, which was accomplished by increased oxidative stress and susceptibility to apoptosis. These alterations induced by IPL were more notorious in the DMBA sensitized skin. Keratins and metabolic proteins seem to be the more susceptible to oxidative modifications that might result in loss of function, contributing for the histological changes observed in treated skin., Conclusion: Data highlight the deleterious impact of IPL on skin phenotype, which justifies the need for more experimental studies in order to increase our understanding of the IPL long-term safety., (Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)