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1.
Front Physiol ; 15: 1415037, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39086932

RESUMO

Background: Carbon dioxide (CO2), traditionally viewed as a mere byproduct of cellular respiration, plays a multifaceted role in human physiology beyond simple elimination through respiration. CO2 may regulate the tumor microenvironment by significantly affecting the release of oxygen (O2) to tissues through the Bohr effect and by modulating blood pH and vasodilation. Previous studies suggest hypercapnia (elevated CO2 levels) might trigger optimized cellular mechanisms with potential therapeutic benefits. The role of CO2 in cellular stress conditions within tumor environments and its impact on O2 utilization offers a new investigative area in oncology. Objectives: This study aims to explore CO2's role in the tumor environment, particularly how its physiological properties and adaptive responses can influence therapeutic strategies. Methods: By applying a structured translational approach using the Work Breakdown Structure method, the study divided the analysis into six interconnected work packages to comprehensively analyze the interactions between carbon dioxide and the tumor microenvironment. Methods included systematic literature reviews, data analyses, data integration for identifying critical success factors and exploring extracellular environment modulation. The research used SMART criteria for assessing innovation and the applicability of results. Results: The research revealed that the human body's adaptability to hypercapnic conditions could potentially inform innovative strategies for manipulating the tumor microenvironment. This could enhance O2 utilization efficiency and manage adaptive responses to cellular stress. The study proposed that carbon dioxide's hormetic potential could induce beneficial responses in the tumor microenvironment, prompting clinical protocols for experimental validation. The research underscored the importance of pH regulation, emphasizing CO2 and carbonic acid's role in modulating metabolic and signaling pathways related to cancer. Conclusion: The study underscores CO2 as vital to our physiology and suggests potential therapeutic uses within the tumor microenvironment. pH modulation and cellular oxygenation optimization via CO2 manipulation could offer innovative strategies to enhance existing cancer therapies. These findings encourage further exploration of CO2's therapeutic potential. Future research should focus on experimental validation and exploration of clinical applications, emphasizing the need for interdisciplinary and collaborative approaches to tackle current challenges in cancer treatment.

2.
Int J Mol Sci ; 25(15)2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39126001

RESUMO

Breast cancer is the most diagnosed type of cancer worldwide and the second cause of death in women. Triple-negative breast cancer (TNBC) is the most aggressive, and due to the lack of specific targets, it is considered the most challenging subtype to treat and the subtype with the worst prognosis. The present study aims to determine the antitumor effect of beta-D-glucose-reduced silver nanoparticles (AgNPs-G) in a murine model of TNBC, as well as to study its effect on the tumor microenvironment. In an airbag model with 4T1 tumor cell implantation, the administration of AgNPs-G or doxorubicin showed antitumoral activity. Using immunohistochemistry it was demonstrated that treatment with AgNPs-G decreased the expression of PCNA, IDO, and GAL-3 and increased the expression of Caspase-3. In the tumor microenvironment, the treatment increased the percentage of memory T cells and innate effector cells and decreased CD4+ cells and regulatory T cells. There was also an increase in the levels of TNF-α, IFN-γ, and IL-6, while TNF-α was increased in serum. In conclusion, we suggest that AgNPs-G treatment has an antitumor effect that is demonstrated by its ability to remodel the tumor microenvironment in mice with TNBC.


Assuntos
Glucose , Nanopartículas Metálicas , Prata , Neoplasias de Mama Triplo Negativas , Microambiente Tumoral , Animais , Microambiente Tumoral/efeitos dos fármacos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/metabolismo , Prata/química , Nanopartículas Metálicas/química , Feminino , Camundongos , Glucose/metabolismo , Linhagem Celular Tumoral , Modelos Animais de Doenças , Camundongos Endogâmicos BALB C , Doxorrubicina/farmacologia , Humanos
3.
Clin Transl Oncol ; 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39122983

RESUMO

BACKGROUND: To investigate the impact of the tumor microenvironment (TME) on the responsiveness to chemotherapy in ovarian cancer (OV). METHODS: We integrated single cell RNA-seq datasets of OV containing chemo-response information, and characterize their clusters based on different TME sections. We focus on analyzing cell-cell communication to elaborate on the mechanisms by which different components of the TME directly influence the chemo-response of tumor cells. RESULTS: scRNA-seq datasets were annotated according to specific markers for different cell types. Differential analysis of malignant epithelial cells revealed that chemoresistance was associated with the TME. Notably, distinct TME components exhibited varying effects on chemoresistance. Enriched SPP1+ tumor-associated macrophages in chemo-resistant patients could promote chemoresistance through SPP1 binding to CD44 on tumor cells. Additionally, the overexpression of THBS2 in stromal cells could promote chemoresistance through binding with CD47 on tumor cells. In contrast, GZMA in the lymphocytes could downregulate the expression of PARD3 through direct interaction with PARD3, thereby attenuating chemoresistance in tumor cells. CONCLUSION: Our study indicates that the non-tumor cell components of the TME (e.g. SPP1+ TAMs, stromal cells and lymphocytes) can directly impact the chemo-response of OV and targeting the TME was potentially crucial in chemotherapy of OV.

4.
Artigo em Inglês | MEDLINE | ID: mdl-39007523

RESUMO

Solid tumors represent the most common type of cancer in humans and are classified into sarcomas, lymphomas, and carcinomas based on the originating cells. Among these, carcinomas, which arise from epithelial and glandular cells lining the body's tissues, are the most prevalent. Around the world, a significant increase in the incidence of solid tumors is observed during recent years. In this context, efforts to discover more effective cancer treatments have led to a deeper understanding of the tumor microenvironment (TME) and its components. Currently, the interactions between cancer cells and elements of the TME are being intensely investigated. Remarkable progress in research is noted, largely owing to the development of advanced in vitro models, such as tumor-on-a-chip models that assist in understanding and ultimately discovering new effective treatments for a specific type of cancer. The purpose of this article is to provide a review of the TME and cancer cell components, along with the advances on tumor-on-a-chip models designed to mimic tumors, offering a perspective on the current state of the art. Recent studies using this kind of microdevices that reproduce the TME have allowed a better understanding of the cancer and its treatments. Nevertheless, current applications of this technology present some limitations that must be overcome to achieve a broad application by researchers looking for a deeper knowledge of cancer and new strategies to improve current therapies.

5.
Clin Transl Oncol ; 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38971914

RESUMO

Exosomes, measuring between 30 and 150 nm in diameter, are small vesicles enclosed by a lipid bilayer membrane. They are released by various cells in the body and carry a diverse payload of molecules, including proteins, lipids, mRNA, and different RNA species such as long non-coding RNA, circular RNA, and microRNA (miRNA). With lengths of approximately 19-22 nucleotides, miRNAs constitute the predominant cargo in exosomes and serve as crucial regulators of protein biosynthesis. In cancer detection, exosomal miRNAs show promise as non-invasive biomarkers due to their stability and presence in various bodily fluids, aiding in early detection and precise diagnosis with specific miRNA signatures linked to different cancer types. Moreover, exosomal miRNAs influence treatment outcomes by affecting cellular processes like cell growth, cell death, and drug resistance, thereby impacting response to therapy. Additionally, they serve as indicators of disease progression and treatment response, providing insights that can guide treatment decisions and improve patient care. Through longitudinal studies, changes in exosomal miRNA profiles have been observed to correlate with disease progression, metastasis, and response to therapy, highlighting their potential for real-time monitoring of tumor dynamics and treatment efficacy. Understanding the intricate roles of exosomal miRNAs in cancer biology offers opportunities for developing innovative diagnostic tools and therapeutic strategies tailored to individual patients, ultimately advancing precision medicine approaches and improving outcomes for cancer patients. This review aims to provide an understanding of the role of exosomal miRNAs in cancer detection, treatment, and monitoring, shedding light on their potential for revolutionising oncology practices and patient care.

6.
Anim Reprod ; 21(2): e20230063, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39021495

RESUMO

Lipid metabolism is essential for ensuring oocyte maturation and embryo development. ß-Oxidized fatty acids (FA) are a potent source of energy for cells, particularly for bovine somatic follicular cells. Superstimulatory protocols using follicle stimulating hormone (FSH) or FSH combined with equine chorionic gonadotropin (eCG) are capable of stimulating the follicular microenvironment and drive the expression of biomarker genes associated with lipid metabolism in the cumulus-oocyte complex (COC) for better embryo development. In this study, we assesed the effects of FSH and FSH/eCG protocols on the expression of genes related to lipid metabolism in bovine granulosa cells (GCs). Further, we measured triglyceride levels in follicular fluid (FF) obtained from both superstimulatd and non-superstimulated cows (synchronized cows). In summary, superstimulation with gonadotropins maintained the TG levels in bovine FF and ensured GCs mRNA abundance of ACSL1, ACSL3, ACSL6, SCD, ELOVL5, ELOVL6, FASN, FADS2, and SREBP1. We, however, found the abundance of CPTIB mRNA to be lower in GCs obtained from cows subjected to FSH/eCG protocols than synchronized cows. In conclusion, the findings of this study showed that ovarian superstimulation around the preovulatory phase has a mild impact on the lipid metabolism in GCs.

7.
Med Int (Lond) ; 4(5): 46, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38983795

RESUMO

Breast cancer (BC) is the leading cause of cancer-related mortality among women worldwide. Immunotherapies are a promising approach in cancer treatment, particularly for aggressive forms of BC with high mortality rates. However, the current eligibility for immunotherapy remains limited to a limited fraction of patients with BC. Myeloid-derived suppressor cells (MDSCs), originating from myeloid cells, are known for their dual role in immunosuppression and tumor promotion, significantly affecting patient outcomes by fostering the formation of premetastatic niches. Consequently, targeting MDSCs has emerged as a promising avenue for further exploration in therapeutic interventions. Leveraging nanotechnology-based drug delivery systems, which excel in accumulating drugs within tumors via passive or active targeting mechanisms, are a promising strategy for the use of MDSCs in the treatment of BC. The present review discusses the immunosuppressive functions of MDSCs, their role in BC, and the diverse strategies for targeting them in cancer therapy. Additionally, the present review discusses future advancements in BC treatments focusing on MDSCs. Furthermore, it elucidates the mechanisms underlying MDSC activation, recruitment and differentiation in BC progression, highlighting the clinical characteristics that render MDSCs suitable candidates for the therapy and targeted nanotherapy of BC.

8.
Heliyon ; 10(12): e32762, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38988554

RESUMO

The use of vegetation in cities is one of the most promising strategies for urban climate change adaptation and mitigation. Tree shade influences heat storage from surfaces reducing long wave radiation emission which directly affects people. People 's heat perception depends more on insolation and the temperature of surrounding objects than on air temperature itself. There is a need for analyzes that include the combined effects of physical and human variables on thermal comfort, as well as location-based studies to address its climatic and social conditions. In order to compare the effect of the trees on microenvironmental temperature and perceived thermal comfort, we measured physical parameters and performed structured interviews on three downtown streets of Montevideo, Uruguay, which had sections with and without trees on four dates during the summer. Generally, people surveyed under both treatments stated they did not feel fully comfortable due to summer heat, but the proportion of people who stated feeling in thermal comfort under tree shade was more than double than the unshaded sections. The seasonal ARIMA analysis supported that the tree shade reduced the microenvironmental temperature by its effect on radiant temperature. By using a statistical decision tree methodology that combines all the variables in the same analysis, we found a greater impact of physical variables than personal variables on people's thermal comfort and thermal preferences. We also identified gender as a significant variable that affects people's thermal preferences, where 46.4 % of females preferred a slightly colder environment.

9.
Expert Rev Endocrinol Metab ; : 1-9, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38975697

RESUMO

INTRODUCTION: The global incidence of thyroid cancer (TC) has increased in the last decades. While improvements in diagnosis may contribute, overdiagnosis is also a possibility. This review focuses on the epidemiology, risk factors, and immune microenvironment associated with differentiated TC (DTC). AREAS COVERED: A search was conducted in Scielo, Scopus, and EMBASE databases, involving 72 articles. TC is the most common endocrine neoplasm, with DTC form being predominant. Its incidence has globally risen, particularly among women aged over 45. Endogenous risk factors for DTC include genetic disorders, race, age, female gender, obesity, and type 2 diabetes mellitus. Environmental risks involve ionizing radiation, whether through therapeutic treatment or environmental contamination from nuclear accidents, iodine deficiency, endocrine disruptors, residence in volcanic areas, environmental pollution, and stress. The use of anti-obesity medications remains controversial. The tumor's immune microenvironment is the histological space where tumor cells interact with host cells, crucial for understanding aggressiveness. Immunotherapy emerges as a promising intervention. EXPERT OPINION: Recent advances in DTC management offer transformative potential, requiring collaborative efforts for implementation. Emerging areas like precision medicine, molecular profiling, and immunotherapy present exciting prospects for future exploration, shaping the next era of diagnostic and therapeutic strategies in thyroid cancer research.


The global incidence of thyroid cancer (TC) has significantly increased, attributed partly to improved diagnosis and potentially to overdiagnosis. This review focuses on the epidemiology, risk factors, and immune microenvironment associated with differentiated TC (DTC). DTC is the most common endocrine neoplasm, and predominantly affects women over 45 years old. Endogenous risk factors include genetic disorders, race, age, female gender, obesity, and type 2 diabetes mellitus (T2DM). Environmental risks encompass ionizing radiation, iodine deficiency, endocrine disruptors, volcanic residence, pollution, and stress. The use of glucagon-like peptide 1 agonists remains controversial. The tumor's immune microenvironment is crucial for understanding aggressiveness, with immunotherapy showing promise. Understanding both macro and microenvironmental factors is crucial for devising effective prevention and treatment strategies for DTC.

10.
Clin Transl Oncol ; 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39083142

RESUMO

PURPOSE: This study aims to develop radiomics models and a nomogram based on machine learning techniques, preoperative dual-energy computed tomography (DECT) images, clinical and pathological characteristics, to explore the tumor microenvironment (TME) of clear cell renal cell carcinoma (ccRCC). METHODS: We retrospectively recruited of 87 patients diagnosed with ccRCC through pathological confirmation from Center I (training set, n = 69; validation set, n = 18), and collected their DECT images and clinical information. Feature selection was conducted using variance threshold, SelectKBest, and the least absolute shrinkage and selection operator (LASSO). Radiomics models were then established using 14 classifiers to predict TME cells. Subsequently, we selected the most predictive radiomics features to calculate the radiomics score (Radscore). A combined model was constructed through multivariate logistic regression analysis combining the Radscore and relevant clinical characteristics, and presented in the form of a nomogram. Additionally, 17 patients were recruited from Center II as an external validation cohort for the nomogram. The performance of the models was assessed using methods such as the area under the receiver operating characteristic curve (AUC), calibration curve, and decision curve analysis (DCA). RESULTS: The validation set AUC values for the radiomics models assessing CD8+, CD163+, and αSMA+ cells were 0.875, 0.889, and 0.864, respectively. Additionally, the external validation cohort AUC value for the nomogram reaches 0.849 and shows good calibration. CONCLUSION: Radiomics models could allow for non-invasive assessment of TME cells from DECT images in ccRCC patients, promising to enhance our understanding and management of the tumor.

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