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1.
Cancer Cell Int ; 24(1): 233, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38965615

RESUMEN

MicroRNAs (miRNAs) are small RNA molecules that regulate genes and are involved in various biological processes, including cancer development. Researchers have been exploring the potential of miRNAs as therapeutic agents in cancer treatment. Specifically, targeting the mammalian target of the rapamycin (mTOR) pathway with miRNAs has shown promise in improving the effectiveness of radiotherapy (RT), a common cancer treatment. This review provides an overview of the current understanding of miRNAs targeting mTOR as therapeutic agents to enhance RT outcomes in cancer patients. It emphasizes the importance of understanding the specific miRNAs that target mTOR and their impact on radiosensitivity for personalized cancer treatment approaches. The review also discusses the role of mTOR in cell homeostasis, cell proliferation, and immune response, as well as its association with oncogenesis. It highlights the different ways in which miRNAs can potentially affect the mTOR pathway and their implications in immune-related diseases. Preclinical findings suggest that combining mTOR modulators with RT can inhibit tumor growth through anti-angiogenic and anti-vascular effects, but further research and clinical trials are needed to validate the efficacy and safety of using miRNAs targeting mTOR as therapeutic agents in combination with RT. Overall, this review provides a comprehensive understanding of the potential of miRNAs targeting mTOR to enhance RT efficacy in cancer treatment and emphasizes the need for further research to translate these findings into improved clinical outcomes.

2.
Curr Top Med Chem ; 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38797895

RESUMEN

In recent years, mesenchymal stem cells (MSCs) have emerged as promising anti-- cancer mediators with the potential to treat several cancers. MSCs have been modified to produce anti-proliferative, pro-apoptotic, and anti-angiogenic molecules that could be effective against a variety of malignancies. Additionally, customizing MSCs with cytokines that stimulate pro-tumorigenic immunity or using them as vehicles for traditional chemical molecules with anti-cancer characteristics. Even though the specific function of MSCs in tumors is still challenged, promising outcomes from preclinical investigations of MSC-based gene therapy for a variety of cancers inspire the beginning of clinical trials. In addition, the tumor microenvironment (TME) could have a substantial influence on normal tissue stem cells, which can affect the treatment outcomes. To overcome the complications of TME in cancer development, MSCs could provide some signs of hope for converting TME into unequivocal therapeutic tools. Hence, this review focuses on engineered MSCs (En-MSCs) as a promising approach to overcoming the complications of TME.

3.
Heliyon ; 9(8): e19236, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37664747

RESUMEN

Background and objective: Pulmonary fibrosis (PF) is a chronic and progressive respiratory disease representing the final stage of lung inflammatory disorders. Reactive oxygen species (ROS), an essential factor in the formation and progression of pulmonary fibrosis, are a significant adverse effect of Bleomycin (BLM). Antioxidant activities have been found in Daphne oleoides. In this study, we attempted to explore the function of hydroalcoholic extract of Daphne oleoides (D. oleoides) and Betulin in inhibiting bleomycin (BLM)-induced pulmonary fibrosis in rat". Materials and methods: The current experimental study used 36 male Wistar rats (180-220). Following a random process, the animals were divided into six groups six (n = 6). Group, I (the control group) received normal saline, while Group II (the hazardous group) received intratracheal BLM (7.5 units per kg). Following the administration of BLM, Groups V and VI received daily doses of vitamin E (500 mg/kg/d, p.o.) and Betulin (10 mg kg/d, p.o.), whereas Groups III and IV received daily doses of Daphne oleoides extract (300 and 600 mg/kg/d, p.o.). Then, blood samples from the hearts of the animals were taken to assess the plasma concentrations of nitric oxide (NO) and malondialdehyde (MDA). Finally, the rats were euthanized, and the lung tissues were taken out for histological analysis and assessments of the levels of lung hydroxyproline (HP), ferric-reducing ability (FRAP), NO, Glutathione Concentration (GSH), thiol content (tSH) and MDA. Findings: Elevated lung index, lung hydroxyproline, NO, and MDA plasma levels, and a reduction in total body thiol content (tSH) in the group receiving BLM were evidence of pulmonary toxicity. Treatment with D. oleoides extracts, Betulin, and Vit E, especially at 600 mg/kg, led to a marked reduction in the above parameters compared with the BLM-received group (p < 0.01). Histological Analysis of the BLM-treated group showed a considerable Lung injury with interstitial infiltration, collapsed alveolar spaces, and alveolar septal thickening. These changes were mitigated with D. oleoides 600, Betulin-, and vitamin E. These changes were mitigated with D. oleoides 600, Betulin-, and vitamin E. Conclusion: These findings suggest that D. oleoides and Betulin prevent bleomycin-induced lung fibrosis in rats by decreasing inflammatory and antioxidant markers. Daphne oleoides, therefore, have the potential to be used therapeutically to treat pulmonary fibrosis.

4.
Clin Breast Cancer ; 23(7): e480-e490.e3, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37596147

RESUMEN

BACKGROUND: About 70%-80% of breast cancers (BCs) express estrogen receptors (ER-positive). MicroRNAs (miRNAs) are a group of small endogenous noncoding RNAs that play a critical regulatory role in cancer development and progression, including in BC. MiRNA deficiency promotes the development of BCs. MiR-143-5p is one of the most commonly dysregulated miRNAs in BC but its role as a tumor suppressor remains unclear. MATERIALS AND METHODS: MiR-143-3p and -5p expression in breast tissue was analyzed using TCGA and StarBase databases. Expression in BC subclasses and survival analyses were conducted. Clinical samples were collected, cell cultures created, and gene expression assays performed following previous studies. Protein expression, luciferase reporter, wound healing, DAPI staining, cell cycle, colony formation, spheroid, CD44 FACS, and proliferation assays were conducted following various protocols. RESULTS: Here, we find that both miR-143-3p and miR-143-5p levels are considerably lower in BC tissue compared to normal breast tissue and low miR-143 expression predicts poor prognosis in ER+ BC patients. In-depth analyses identified 3 miR-143-5p binding sites in the 3' untranslated region (UTR) of the DNA binding protein High Mobility Group AT-Hook 2 (HMGA2). Luciferase reporter assays using wild-type and mutant HMGA2 3'UTR sequences and Western blot analyses demonstrated that HMGA2 is a direct and bona fide miR-143-5p target in BC cells. In addition, we show that restoration of miR-143-5p expression suppresses metastasis-related features of ER+ BC cells, including reduced tumor cell migration, increased E-cadherin expression, and decreased vimentin and N-cadherin expression. Furthermore, miR-143-5p reduces cell proliferation, cell cycle entry, and stemness, while promoting apoptosis moderately. Finally, patient sample pathway analyses demonstrated that these mechanisms are also active in BC. CONCLUSIONS: Altogether, our findings shed new light on miR-143-5p's anticancer biological functions in BC progression by directly targeting HMGA2. This suggests that restoration of miR-143-5p could be a promising new therapeutic approach for the treatment of ER+ BC.


Asunto(s)
Neoplasias de la Mama , MicroARNs , Femenino , Humanos , Mama/metabolismo , Mama/patología , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , MicroARNs/metabolismo , Receptores de Estrógenos/genética , Receptores de Estrógenos/metabolismo
5.
Viral Immunol ; 36(6): 368-377, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37276047

RESUMEN

According to current knowledge, the etiopathogenesis of multiple sclerosis (MS) is complex, involving genetic background as well as several environmental factors that result in dysimmunity in the central nervous system (CNS). MS is an immune-mediated, inflammatory neurological disease affecting the CNS. As part of its attack on the axons of the CNS, MS witnesses varying degrees of myelin and axonal loss. A total of about 20 disease-modifying therapies (DMTs) are available today that, both in clinical trials and in real-world studies, reduce disease activity, such as relapses, magnetic resonance imaging lesions, and disability accumulation. Currently, the world is facing an outbreak of the new coronavirus disease 2019 (COVID-19), which originated in Wuhan, Hubei Province, China, in December 2019 and spread rapidly around the globe. Viral infections play an important role in triggering and maintaining neuroinflammation through direct and indirect mechanisms. There is an old association between MS and viral infections. In the context of MS-related chronic inflammatory damage within the CNS, there has been concern regarding COVID-19 worsening neurological damage. A high rate of disability and increased susceptibility to infection have made MS patients particularly vulnerable. In addition, DMTs have been a concern during the pandemic since many DMTs have immunosuppressive properties. In this article, we discuss the impact of DMTs on COVID-19 risks and the effect of DMTs on COVID-19 vaccination efficacy and outcome in MS patients.


Asunto(s)
COVID-19 , Esclerosis Múltiple , Humanos , Esclerosis Múltiple/complicaciones , Esclerosis Múltiple/tratamiento farmacológico , COVID-19/prevención & control , Vacunas contra la COVID-19 , Inmunosupresores/uso terapéutico , China
6.
Cancer Res ; 83(15): 2450-2460, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37195095

RESUMEN

The mTOR complex 1 (mTORC1) coordinates several important environmental and intracellular cues to control a variety of biological processes, such as cell growth, survival, autophagy, and metabolism, in response to energy levels, growth signals, and nutrients. The endoplasmic reticulum (ER) is a crucial intracellular organelle that is essential for numerous cellular functions, including the synthesis, folding, and modification of newly synthesized proteins, stress responsiveness, and maintainence of cellular homeostasis. mTOR-mediated upregulation of protein synthesis induces the accumulation of misfolded or unfolded proteins in the ER lumen, which induces ER stress, leading to activation of the unfolded protein response (UPR) pathway. Reciprocally, ER stress regulates the PI3K/AKT/mTOR signaling pathway. Therefore, under pathologic conditions, the cross-talk between the mTOR and UPR signaling pathways during cellular stress can critically affect cancer cell fate and may be involved in the pathogenesis and therapeutic outcome of cancer. Here, we discuss accumulating evidence showing the mechanism of action, interconnections, and molecular links between mTOR signaling and ER stress in tumorigenesis and highlights potential therapeutic implications for numerous cancers.


Asunto(s)
Neoplasias , Fosfatidilinositol 3-Quinasas , Humanos , Fosfatidilinositol 3-Quinasas/metabolismo , Respuesta de Proteína Desplegada , Estrés del Retículo Endoplásmico , Transducción de Señal/fisiología , Serina-Treonina Quinasas TOR/metabolismo
7.
Life Sci ; 315: 121361, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36608871

RESUMEN

TP53 is the most frequently mutated gene in human cancer. It encodes the tumor suppressor protein p53, which suppresses tumorigenesis by acting as a critical transcription factor that can induce the expression of many genes controlling a plethora of fundamental cellular processes, including cell cycle progression, survival, apoptosis, and DNA repair. Missense mutations are the most frequent type of mutations in the TP53 gene. While these can have variable effects, they typically impair p53 function in a dominant-negative manner, thereby altering intra-cellular signaling pathways and promoting cancer development. Additionally, it is becoming increasingly apparent that p53 mutations also have non-cell autonomous effects that influence the tumor microenvironment (TME). The TME is a complex and heterogeneous milieu composed of both malignant and non-malignant cells, including cancer-associated fibroblasts (CAFs), adipocytes, pericytes, different immune cell types, such as tumor-associated macrophages (TAMs) and T and B lymphocytes, as well as lymphatic and blood vessels and extracellular matrix (ECM). Recently, a large body of evidence has demonstrated that various types of p53 mutations directly affect TME. They fine-tune the inflammatory TME and cell fate reprogramming, which affect cancer progression. Notably, re-educating the p53 signaling pathway in the TME may be an effective therapeutic strategy in combating cancer. Therefore, it is timely to here review the recent advances in our understanding of how TP53 mutations impact the fate of cancer cells by reshaping the TME.


Asunto(s)
Neoplasias , Proteína p53 Supresora de Tumor , Humanos , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Genes p53 , Neoplasias/genética , Neoplasias/patología , Carcinogénesis/genética , Transformación Celular Neoplásica/metabolismo , Microambiente Tumoral/genética
8.
Cancers (Basel) ; 14(13)2022 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-35804989

RESUMEN

Glioblastoma (GBM) is an aggressive brain tumor that develops from neuroglial stem cells and represents a highly heterogeneous group of neoplasms. These tumors are predominantly correlated with a dismal prognosis and poor quality of life. In spite of major advances in developing novel and effective therapeutic strategies for patients with glioblastoma, multidrug resistance (MDR) is considered to be the major reason for treatment failure. Several mechanisms contribute to MDR in GBM, including upregulation of MDR transporters, alterations in the metabolism of drugs, dysregulation of apoptosis, defects in DNA repair, cancer stem cells, and epithelial-mesenchymal transition. MicroRNAs (miRNAs) are a large class of endogenous RNAs that participate in various cell events, including the mechanisms causing MDR in glioblastoma. In this review, we discuss the role of miRNAs in the regulation of the underlying mechanisms in MDR glioblastoma which will open up new avenues of inquiry for the treatment of glioblastoma.

9.
Iran J Allergy Asthma Immunol ; 21(3): 287-299, 2022 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-35822679

RESUMEN

To investigate the effects of everolimus, a mechanistic/mammalian target of rapamycin (mTOR) inhibitor, on tumor growth and immune response in a mouse model of breast cancer. Human hormone receptor-positive (HR+)/human epidermal growth receptor 2-negative (HER2-) MC4-L2 cell line was used to establish a mouse model of breast cancer. The inhibitory effects of high (10 mg/kg) and low (5 mg/kg) doses of everolimus were investigated on tumor growth. Additionally, the frequency of CD4+Foxp3+ regulatory T cells (Tregs), CD8+Foxp3+ Tregs, and CD4+ and CD8+ T cells expressing cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) was explored by flow cytometry in bone marrow, lymph nodes, and spleen. Our results showed that both 10 mg/kg and 5 mg/kg doses of everolimus efficiently inhibited tumor growth, resulting in reduced breast tumor volume. In addition, it was revealed that everolimus-treated mice induced a higher frequency of CD4+Foxp3+ Tregs, CD8+Foxp3+ Tregs, and CD4+Foxp3+CTLA-4+ Tregs as well as CD4+ and CD8+ T cells expressing CTLA-4 in their bone marrow, lymph nodes, and spleen compared with standard control (vehicle-treated) in a dose-dependent manner. Furthermore, we found that everolimus treatment with 10 mg/kg and 5 mg/kg increased the frequency of Helios+Foxp3+ Tregs in the bone marrow of treated mice compared with the control group. Our results indicate that treatment with everolimus not only inhibits tumor growth but also exerts an immunomodulatory effect by inducing Tregs in the lymphoid organs of breast cancer-bearing mice. The combination of therapy with other anti-cancer agents may negate immune suppression and improve the efficacy of mTOR-targeted breast cancer therapy.


Asunto(s)
Neoplasias de la Mama , Sirolimus , Animales , Neoplasias de la Mama/tratamiento farmacológico , Antígeno CTLA-4 , Modelos Animales de Enfermedad , Everolimus/farmacología , Everolimus/uso terapéutico , Femenino , Factores de Transcripción Forkhead/metabolismo , Humanos , Mamíferos/metabolismo , Ratones , Sirolimus/farmacología , Sirolimus/uso terapéutico , Serina-Treonina Quinasas TOR/metabolismo
10.
Cell Commun Signal ; 20(1): 106, 2022 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-35842705

RESUMEN

BACKGROUND: The COVID-19 pandemic has become the world's main life-threatening challenge in the third decade of the twenty-first century. Numerous studies have been conducted on SARS-CoV2 virus structure and pathogenesis to find reliable treatments and vaccines. The present study aimed to evaluate the immune-phenotype and IFN-I signaling pathways of COVID-19 patients with mild and severe conditions. MATERIAL AND METHODS: A total of 100 COVID-19 patients (50 with mild and 50 with severe conditions) were enrolled in this study. The frequency of CD4 + T, CD8 + T, Th17, Treg, and B lymphocytes beside NK cells was evaluated using flow cytometry. IFN-I downstream signaling molecules, including JAK-1, TYK-2, STAT-1, and STAT-2, and Interferon regulatory factors (IRF) 3 and 7 expressions at RNA and protein status were investigated using real-time PCR and western blotting techniques, respectively. Immune levels of cytokines (e.g., IL-1ß, IL-6, IL-17, TNF-α, IL-2R, IL-10, IFN-α, and IFN-ß) and the existence of anti-IFN-α autoantibodies were evaluated via enzyme-linked immunosorbent assay (ELISA). RESULTS: Immune-phenotyping results showed a significant decrease in the absolute count of NK cells, CD4 + T, CD8 + T, and B lymphocytes in COVID-19 patients. The frequency of Th17 and Treg cells showed a remarkable increase and decrease, respectively. All signaling molecules of the IFN-I downstream pathway and IRFs (i.e., JAK-1, TYK-2, STAT-1, STAT-2, IRF-3, and IRF-7) showed very reduced expression levels in COVID-19 patients with the severe condition compared to healthy individuals at both RNA and protein levels. Of 50 patients with severe conditions, 14 had anti-IFN-α autoantibodies in sera. Meanwhile, this result was 2 and 0 for patients with mild symptoms and healthy controls, respectively. CONCLUSION: Our results indicate a positive association of the existence of anti-IFN-α autoantibodies and immune cells dysregulation with the severity of illness in COVID-19 patients. However, comprehensive studies are necessary to find out more about this context. Video abstract.


Asunto(s)
COVID-19 , Autoanticuerpos , Citocinas/metabolismo , Humanos , Interferones , Células Asesinas Naturales , Pandemias , ARN Viral , SARS-CoV-2 , Transducción de Señal
11.
Artículo en Inglés | MEDLINE | ID: mdl-35722156

RESUMEN

Background: Stachys L. (Lamiaceae) includes more than 300 annual or perennial species growing in temperate regions of Southern Africa, the Mediterranean, America, and Asia. Stachys pilifera Benth (S. pilifera), also known as Marzeh Kuhi, is an endemic species from Iran. It is found in the mountainous habitats of the Zagros area. It has various traditional uses, and the phytochemical ingredients and some biological activities of this species have been examined in previous studies. Methods: PubMed, Science Direct, Google Scholar, Scopus, and Science Web databases were used to gather the data. The purpose of this review is to consolidate the scattered knowledge reported in the literature about botany, traditional uses, phytochemistry, pharmacological properties, and safety of S. pilifera and suggest its potential medicinal properties. Key Findings. In traditional Iranian medicine, S. pilifera manages various illnesses, such as rheumatoid arthritis, common cold, infections, asthma, and tussive. More than 30 compounds have been identified in S. pilifera essential oil. The compounds found in S. pilifera are phenolic compounds, monoterpenes, sesquiterpenes, flavonoids, alkaloids, and terpenoids, which have various properties such as antioxidant, nephroprotective, anti-inflammatory, antimicrobial, hepatoprotective, and anticancer properties. Conclusions: The literature reveals that S. pilifera is an essential source of bioactive phytochemicals and illustrates the unknown area of this plant for new investigations. Moreover, we recommend that future research focus on toxicology and quality control studies for S. pilifera to fill the knowledge gap and provide theoretical support for the plant's possible functional and clinical uses.

12.
Artículo en Inglés | MEDLINE | ID: mdl-38059201

RESUMEN

Methods: In this experimental study, 35 male Wistar rats (120-180 g) were divided into five groups (n = 7) as follows: intratracheal instillation of bleomycin (BLM, 7.5 IU/kg) was administered to group II. The third and fourth groups received BLM plus Stachys pilifera hydroalcoholic extract (SPHE) (300 mg/kg/day, gavage). Vitamin E (500 mg/kg/day, gavage) was given to group V in addition to BLM. After 14 days, the animals were euthanized to assess biochemical parameters and lung histopathology. Malondialdehyde (MDA), nitric oxide (NO), total thiol (TSH), and glutathione (GSH) levels were measured. In addition, hydroxyproline (HYP) levels along with histological changes in lung tissue were also assessed. Results: MDA, NO, and HYP elevations induced by BLM toxicity were significantly inhibited by SPHE (300 and 600 mg/kg), and Vit E. SPHE also significantly increased GSH and TSH levels in comparison to the BLM group.HPLC analyses showed the presence of thymol (55.47 ng/mL) and carvacrol (109.91 ng/mL) in SPHE as potential bioactive phenolic compounds. Conclusion: The results suggest that SPHE alleviates the development of BLM-induced pulmonary fibrosis by inhibiting the proliferation of fibroblasts mediated by antioxidant pathways. Other mechanisms underlying this Effect of SPHE need to be clarified through further research.

13.
Front Immunol ; 12: 774103, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35250965

RESUMEN

The mechanistic/mammalian target of rapamycin (mTOR) is a downstream mediator in the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathways, which plays a pivotal role in regulating numerous cellular functions including cell growth, proliferation, survival, and metabolism by integrating a variety of extracellular and intracellular signals in the tumor microenvironment (TME). Dysregulation of the mTOR pathway is frequently reported in many types of human tumors, and targeting the PI3K/Akt/mTOR signaling pathway has been considered an attractive potential therapeutic target in cancer. The PI3K/Akt/mTOR signaling transduction pathway is important not only in the development and progression of cancers but also for its critical regulatory role in the tumor microenvironment. Immunologically, mTOR is emerging as a key regulator of immune responses. The mTOR signaling pathway plays an essential regulatory role in the differentiation and function of both innate and adaptive immune cells. Considering the central role of mTOR in metabolic and translational reprogramming, it can affect tumor-associated immune cells to undergo phenotypic and functional reprogramming in TME. The mTOR-mediated inflammatory response can also promote the recruitment of immune cells to TME, resulting in exerting the anti-tumor functions or promoting cancer cell growth, progression, and metastasis. Thus, deregulated mTOR signaling in cancer can modulate the TME, thereby affecting the tumor immune microenvironment. Here, we review the current knowledge regarding the crucial role of the PI3K/Akt/mTOR pathway in controlling and shaping the immune responses in TME.


Asunto(s)
Neoplasias , Serina-Treonina Quinasas TOR , Microambiente Tumoral , Humanos , Inmunidad , Neoplasias/inmunología , Fosfatidilinositol 3-Quinasa/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Microambiente Tumoral/inmunología
14.
Biomed Pharmacother ; 80: 30-41, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27133037

RESUMEN

Rheumatoid arthritis (RA) is one of the common and severe autoimmune diseases related to joints. This chronic autoimmune inflammatory disease, leads to functional limitation and reduced quality of life, since as there is bone and cartilage destruction, joint swelling and pain. Current advances and new treatment approaches have considerably postponed disease progression and improved the quality of life for many patients. In spite of major advances in therapeutic options, restrictions on the routes of administration and the necessity for frequent and long-term dosing often result in systemic adverse effects and patient non-compliance. Unlike usual drugs, nanoparticle systems are planned to deliver therapeutic agents especially to inflamed synovium, so avoiding systemic and unpleasant effects. The present review discusses about some of the most successful drugs in RA therapy and their side effects and also focuses on key design parameters of RA-targeted nanotechnology-based strategies for improving RA therapies.


Asunto(s)
Artritis Reumatoide/terapia , Nanopartículas/uso terapéutico , Nanotecnología/métodos , Portadores de Fármacos/química , Humanos
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