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Neosetophomone B (NSP-B) is a unique meroterpenoid fungal secondary metabolite that has previously demonstrated promising anti-cancer properties against various cancer cell lines in vitro. However, its in vivo anti-cancer potential remaines unexplored. To fill this gap in our knowledge, we tested NSP-B's in vivo anti-cancer activity using a zebrafish model, an organism that has gained significant traction in biomedical research due to its genetic similarities with humans and its transparent nature, allowing real-time tumor growth observation. For our experiments, we employed the K562-injected zebrafish xenograft model. Upon treating these zebrafish with NSP-B, we observed a marked reduction in the size and number of tumor xenografts. Delving deeper, our analyses indicated that NSP-B curtailed tumor growth and proliferation of leukemic grafted xenograft within the zebrafish. These results show that NSP-B possesses potent in vivo anti-cancer properties, making it a potential novel therapeutic agent for addressing hematological malignancies.
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Neoplasias , Peixe-Zebra , Animais , Humanos , Peixe-Zebra/metabolismo , Xenoenxertos , Modelos Animais de Doenças , Linhagem Celular Tumoral , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Cancer 'stemness' is fundamental to cancer existence. It defines the ability of cancer cells to indefinitely perpetuate as well as differentiate. Cancer stem cell populations within a growing tumor also help evade the inhibitory effects of chemo- as well as radiation-therapies, in addition to playing an important role in cancer metastases. NF-κB and STAT-3 are representative transcription factors (TFs) that have long been associated with cancer stemness, thus presenting as attractive targets for cancer therapy. The growing interest in non-coding RNAs (ncRNAs) in the recent years has provided further insight into the mechanisms by which TFs influence cancer stem cell characteristics. There is evidence for a direct regulation of TFs by ncRNAs, such as, microRNAs (miRNAs), long non-coding RNAs (lncRNAs) as well as circular RNAs (circRNAs), and vice versa. Additionally, the TF-ncRNAs regulations are often indirect, involving ncRNA-target genes or the sponging of other ncRNA species by individual ncRNAs. The information is rapidly evolving and this review provides a comprehensive review of TF-ncRNAs interactions with implications on cancer stemness and in response to therapies. Such knowledge will help uncover the many levels of tight regulations that control cancer stemness, providing novel opportunities and targets for therapy in the process.
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MicroRNAs , Neoplasias , Humanos , Fatores de Transcrição/genética , RNA não Traduzido/genética , MicroRNAs/genética , Neoplasias/genética , Epigênese GenéticaRESUMO
Macrophages are immune cells that play different roles under different physiological conditions. They are present in all tissues where they primarily protect from bacteria and pathogens in addition to assisting in tissue repair. During tumor progression, macrophages can exert contrasting effects based on the M1 vs. M2 polarization. The M2 macrophages support tumor growth through mechanisms that help suppress immune responses and/or circumvent immune-surveillance. A number of such mechanisms such as production of IL-10 and arginase, and expression of PD-L1, V-domain Ig suppressor of T cell activation and B7 family molecule B7-H4 are now believed central to the immunosuppressive effects of tumor-associated macrophages (TAMs). Emerging data has identified epigenetic regulation of these immunosuppressive mechanisms by small non-coding RNAs, the microRNAs (miRNAs). This review discusses the available literature on the subject, including the exosomes mediated transfer of miRNAs between cancer cells and the macrophages within the tumor microenvironment. A number of miRNAs are now believed to be involved in TAMs' production of IL-10 and expression of PD-L1 while the information on such regulation of other immunosuppressive mechanisms is slowly emerging. A better understanding of epigenetic regulation of macrophages-mediated immunosuppressive effect can help identify novel targets for therapy and aid the design of future studies aimed at sensitizing tumors to immune responses.
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MicroRNAs , Neoplasias , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Epigênese Genética/genética , Humanos , Interleucina-10/metabolismo , MicroRNAs/genética , Neoplasias/patologia , Microambiente Tumoral/genética , Macrófagos Associados a TumorRESUMO
PURPOSE: To determine whether industry affiliation influences the results of randomized controlled trials (RCTs) studying the use of platelet-rich plasma (PRP) for the treatment of patellar or Achilles tendinopathy. METHODS: The PubMed, Scopus, Cochrane, and MEDLINE databases were searched in July 2023 for RCTs investigating PRP for the treatment of patellar or Achilles tendinopathy published between 2009 and July 2023. Industry affiliation was determined by analyzing each study's funding or conflict-of-interest section. Author disclosures were searched in the American Academy of Orthopaedic Surgeons disclosure database and the Centers for Medicare & Medicaid Services open payments database. An industry-affiliated (IA) designation was given if an author had a relevant disclosure or if the company that funded the study manufactured PRP. Otherwise, a non-industry-affiliated (NIA) designation was given. Fisher exact analysis was used to determine whether PRP had a favorable effect, no significant effect, or an unfavorable effect on outcome. RESULTS: Analysis was performed on 22 studies (10 IA and 12 NIA), with 17 studies (77.3%) reporting a conflict of interest or funding for the research, 4 (18.2%) reporting no conflict of interest, and 1 (4.5%) with no reporting. Of the 22 included studies, 8 (36.4%) reported favorable outcomes regarding PRP use and 14 (63.6%) reported no significant effect. Favorable outcomes were found in 4 of the 10 IA studies (40.0%), whereas no significant effect was reported in 6 (60.0%). The 12 NIA studies included 4 (33.3%) with favorable results and 8 (66.7%) with no significant effect. The comparison between industry affiliation and results reported was not statistically significant (P > .999). CONCLUSIONS: The results of RCTs evaluating the use of PRP in lower-extremity tendinopathy were not influenced by industry sponsorship. CLINICAL RELEVANCE: Most biomedical research is funded through industry sponsorship. Although this relation is necessary as technologies are developed, it is important to scrutinize studies for evidence of industry bias to understand how this bias may be affecting study results published in the literature.
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PURPOSE: To present hospital compliance with federal price transparency regulations for sports medicine procedures. METHODS: Online price estimator and machine-readable files were recovered for U.S. News and World Report's top 100 orthopaedic hospitals. From June to November 2023, compliance and monetary values were recorded for each of Centers for Medicare and Medicaid Services price transparency regulations. Price estimator data were assessed on the basis of hospital placement in the bottom and top 50 of the 100 institutions under review, as well as by region (Northeast, South, Midwest, West). Statistical analyses included 2-sample t tests and Kruskal-Wallis tests. RESULTS: In total, 95% of hospitals had a price estimator tool for both subacromial decompression (Current Procedural Terminology [CPT] code 29826) and meniscectomy (CPT code 29881). Only 38% were compliant with all regulations for subacromial decompression and 39% for meniscectomy; the remaining did not list minimum or maximum procedure charges. Higher-ranked hospitals were significantly more likely to charge a greater cash price for subacromial decompression and meniscectomy (P = .040 and P = .009, respectively). Compliance with machine-readable file reporting was poor, with less than 20% meeting requirements for each CPT code. Reported prices varied greatly by hospital. CONCLUSIONS: This study demonstrates that U.S. News and World Report's top 100 orthopaedic hospitals exhibit poor overall compliance with federal price transparency regulations for sports medicine procedures. Most often they lack full compliance by not reporting minimum or maximum charges as part of their price estimator tool or do not report procedure prices in their machine-readable files. Hospitals also exhibit wide variation in prices reported for specific procedures. CLINICAL RELEVANCE: Consumer price transparency continues to be an important goal in health care, as it allows patients to make informed decisions when selecting appropriate treatment options and providers. To realize the full benefits of price transparency, hospitals should address areas of improvement.
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BACKGROUND: Perioperative intravenous (IV) dexamethasone is commonly used in lower extremity total joint arthroplasty to manage postoperative pain and nausea/vomiting, and recent studies have demonstrated that its use may lower rates of acute postoperative medical complications. However, there is limited information regarding the safety and efficacy of IV dexamethasone in patients undergoing total shoulder arthroplasty (TSA). Additionally, there is concern surrounding corticosteroid use prior to surgery as preoperative corticosteroid injections have been associated with adverse outcomes after TSA, including periprosthetic joint infection (PJI) and revision surgery. Thus, the purpose of this study was to evaluate the effect of perioperative IV dexamethasone on 90-day rates of PJI, wound complications, and medical complications after TSA. METHODS: The Premiere national hospital database was used to identify adult patients undergoing elective TSA between 2016 and 2020; patients were excluded if they were under 18 years old, were undergoing revision TSA, or had a prior proximal humerus open reduction internal fixation procedure. Patients who did and did not receive perioperative IV dexamethasone were then compared in both univariate and multivariate analyses. A Bonferroni correction was utilized to adjust for multiple comparisons. The primary end point was risk of acute infectious complications within 90 days of surgery, including PJI and wound infection/dehiscence. Secondary end points included acute pulmonary, renal, and thromboembolic complications. RESULTS: A total of 135,333 patients underwent TSA during the study period; 61.2% underwent reverse total shoulder arthroplasty, 33.8% underwent anatomic total shoulder arthroplasty, and 5.0% underwent hemiarthroplasty. From 2016 to 2020, perioperative IV dexamethasone use increased by 135%. Multivariate analysis revealed that patients who received perioperative IV dexamethasone did not have increased odds of PJI, superficial wound infection, or wound dehiscence (P = .15-.47) but did have decreased odds of sepsis (odds ratio [OR] 0.67, 95% confidence interval [CI] 0.55-0.81) and other medical complications such as urinary tract infection and acute kidney injury. Additionally, there was a trend towards decreased 90-day hospital readmission (OR 0.88, 95% CI 0.81-0.96, P = .003). CONCLUSIONS: Perioperative IV dexamethasone was not associated with increased risk of acute infectious and wound healing complications. Moreover, patients who received perioperative IV dexamethasone had decreased odds of medical complications and trended toward lower rates of 90-day hospital readmission. The results of this study support the safety of perioperative IV dexamethasone use in patients undergoing elective TSA.
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Circular RNAs (circRNAs) are a class of single-stranded closed non-coding RNA molecules (ncRNAs), which are formed as a result of reverse splicing of mRNAs. Despite their relative abundance, an interest in understanding their regulatory importance is rather recent. High stability, abundance and evolutionary conservation among species underline some of their important traits. CircRNAs perform a variety of cellular functions ranging from miRNA and proteins sponges to transcriptional modulation and splicing. Additionally, most circRNAs are expressed aberrantly in pathological conditions suggesting their possible exploitation as diagnostic biomarkers. Their covalent closed cyclic structure resulting in resistance to RNases further makes them suitable as cancer biomarkers. Studies involving human tumors have verified differences in the expression profiles of circRNAs, indicating a regulatory role in cancer pathogenesis and metastasis. As endogenous competitive RNA, circRNAs can regulate tumor proliferation and invasion. Further, some circRNAs located in the nucleus can regulate transcription of genes by binding to RNA polymerase II. In this review, we elaborate the characteristics, functions and mechanisms of action of circRNAs in cancer. We also discuss the possibility of using circRNAs as potential therapeutic targets and biomarkers for cancer.
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MicroRNAs , Neoplasias , Biomarcadores , Biomarcadores Tumorais/genética , Núcleo Celular , Humanos , MicroRNAs/genética , Neoplasias/diagnóstico , Neoplasias/genética , Neoplasias/terapia , RNA Circular/genéticaRESUMO
The skin is the largest organ of the human body and prone to various diseases, including cancer; thus, provides the first line of defense against exogenous biological and non-biological agents. Skin cancer, a complex and heterogenic process, with steep incidence rate often metastasizes due to poor understanding of the underlying mechanisms of pathogenesis and clinical challenges. Indeed, accumulating evidence indicates that deregulation of transcription factors (TFs) due to genetic, epigenetic and signaling distortions plays essential role in the development of cutaneous malignancies and therapeutic challenges including cancer stemness features and reprogramming. This review highlights the recent developments exploring underlying mechanisms how deregulated TFs (e.g., NF-κB, AP-1, STAT etc.,) orchestrates cutaneous onco-pathogenesis, reprogramming, stemness and poor clinical outcomes. Along this line, bioactive drugs, and their derivatives from natural and or synthetic origin has gained attention due to their multitargeting potential, potentially safer and effective therapeutic outcome for human malignancies. We also discussed therapeutic importance of targeting aberrantly expressed TFs in skin cancers with bioactive natural products and or synthetic agents.
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Neoplasias Cutâneas , Fatores de Transcrição , Humanos , Fatores de Transcrição/genética , Carcinogênese , Oncogenes , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/genética , Resultado do TratamentoRESUMO
Since the introduction of the cancer stem cell (CSC) paradigm, significant advances have been made in understanding the functional and biological plasticity of these elusive components in malignancies. Endowed with self-renewing abilities and multilineage differentiation potential, CSCs have emerged as cellular drivers of virtually all facets of tumor biology, including metastasis, tumor recurrence/relapse, and drug resistance. The functional and biological characteristics of CSCs, such as self-renewal, cell fate decisions, survival, proliferation, and differentiation are regulated by an array of extracellular factors, signaling pathways, and pluripotent transcriptional factors. Besides the well-characterized regulatory role of transcription factors OCT4, SOX2, NANOG, KLF4, and MYC in CSCs, evidence for the central role of Forkhead box transcription factor FOXM1 in the establishment, maintenance, and functions of CSCs is accumulating. Conventionally identified as a master regulator of the cell cycle, a comprehensive understanding of this molecule has revealed its multifarious oncogenic potential and uncovered its role in angiogenesis, invasion, migration, self-renewal, and drug resistance. This review compiles the large body of literature that has accumulated in recent years that provides evidence for the mechanisms by which FOXM1 expression promotes stemness in glioblastoma, breast, colon, ovarian, lung, hepatic, and pancreatic carcinomas. We have also compiled the data showing the association of stem cell mediators with FOXM1 using TCGA mRNA expression data. Further, the prognostic importance of FOXM1 and other stem cell markers is presented. The delineation of FOXM1-mediated regulation of CSCs can aid in the development of molecularly targeted pharmacological approaches directed at the selective eradication of CSCs in several human malignancies.
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Glioblastoma , Recidiva Local de Neoplasia , Humanos , Células-Tronco Neoplásicas , Transdução de Sinais , Fatores de Transcrição Forkhead , Proteína Forkhead Box M1/genéticaRESUMO
Inflammation is an essential component of several respiratory diseases, such as chronic obstructive pulmonary disease (COPD), asthma and acute respiratory distress syndrome (ARDS). It is central to lung cancer, the leading cancer in terms of associated mortality that has affected millions of individuals worldwide. Inflammation and pulmonary manifestations are also the major causes of COVID-19 related deaths. Acute hyperinflammation plays an important role in the COVID-19 disease progression and severity, and development of protective immunity against the virus is greatly sought. Further, the severity of COVID-19 is greatly enhanced in lung cancer patients, probably due to the genes such as ACE2, TMPRSS2, PAI-1 and furin that are commonly involved in cancer progression as well as SAR-CoV-2 infection. The importance of inflammation in pulmonary manifestations, cancer and COVID-19 calls for a closer look at the underlying processes, particularly the associated increase in IL-6 and other cytokines, the dysregulation of immune cells and the coagulation pathway. Towards this end, several reports have identified epigenetic regulation of inflammation at different levels. Expression of several key inflammation-related cytokines, chemokines and other genes is affected by methylation and acetylation while non-coding RNAs, including microRNAs as well as long non-coding RNAs, also affect the overall inflammatory responses. Select miRNAs can regulate inflammation in COVID-19 infection, lung cancer as well as other inflammatory lung diseases, and can serve as epigenetic links that can be therapeutically targeted. Furthermore, epigenetic changes also mediate the environmental factors-induced inflammation. Therefore, a better understanding of epigenetic regulation of inflammation can potentially help develop novel strategies to prevent, diagnose and treat chronic pulmonary diseases, lung cancer and COVID-19.
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COVID-19 , Pneumopatias , Neoplasias Pulmonares , MicroRNAs , COVID-19/genética , Citocinas , Epigênese Genética , Humanos , Inflamação/genética , Pneumopatias/genética , Neoplasias Pulmonares/genética , MicroRNAs/genética , SARS-CoV-2RESUMO
Cutaneous T cell lymphomas (CTCLs) are a heterogeneous group of lymphoproliferative neoplasms that exhibit a wide spectrum of immune-phenotypical, clinical, and histopathological features. The biology of CTCL is complex and remains elusive. In recent years, the application of next-generation sequencing (NGS) has evolved our understanding of the pathogenetic mechanisms, including genetic aberrations and epigenetic abnormalities that shape the mutational landscape of CTCL and represent one of the important pro-tumorigenic principles in CTCL initiation and progression. Still, identification of the major pathophysiological pathways including genetic and epigenetic components that mediate malignant clonal T cell expansion has not been achieved. This is of prime importance given the role of malignant T cell clones in fostering T helper 2 (Th2)-bias tumor microenvironment and fueling progressive immune dysregulation and tumor cell growth in CTCL patients, manifested by the secretion of Th2-associated cytokines and chemokines. Alterations in malignant cytokine and chemokine expression patterns orchestrate the inflammatory milieu and influence the migration dynamics of malignant clonal T cells. Here, we highlight recent insights about the molecular mechanisms of CTCL pathogenesis, emphasizing the role of cytokines, chemokines, and associated downstream signaling networks in driving immune defects, malignant transformation, and disease progression. In-depth characterization of the CTCL immunophenotype and tumoral microenvironment offers a facile opportunity to expand the therapeutic armamentarium of CTCL, an intractable malignant skin disease with poor prognosis and in dire need of curative treatment approaches.
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Linfoma Cutâneo de Células T , Neoplasias Cutâneas , Humanos , Citocinas , Quimiocinas , Linfoma Cutâneo de Células T/genética , Transdução de Sinais , Neoplasias Cutâneas/genética , Microambiente Tumoral/genéticaRESUMO
Signaling involving chemokine receptor CXCR4 and its ligand SDF-1/CXL12 has been investigated for many years for its possible role in cancer progression and pathogenesis. Evidence emerging from clinical studies in recent years has further established diagnostic as well as prognostic importance of CXCR4 signaling. CXCR4 and SDF-1 are routinely reported to be elevated in tumors, distant metastases, which correlates with poor survival of patients. These findings have kindled interest in the mechanisms that regulate CXCR4/SDF-1 expression. Of note, there is a particular interest in the epigenetic regulation of CXCR4 signaling that may be responsible for upregulated CXCR4 in primary as well as metastatic cancers. This review first lists the clinical evidence supporting CXCR4 signaling as putative cancer diagnostic and/or prognostic biomarker, followed by a discussion on reported epigenetic mechanisms that affect CXCR4 expression. These mechanisms include regulation by non-coding RNAs, such as, microRNAs, long non-coding RNAs and circular RNAs. Additionally, we also discuss the regulation of CXCR4 expression through methylation and acetylation. Better understanding and appreciation of epigenetic regulation of CXCR4 signaling can invariably lead to identification of novel therapeutic targets as well as therapies to regulate this oncogenic signaling.
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MicroRNAs , Neoplasias , Humanos , Epigênese Genética , Quimiocina CXCL12/genética , Receptores CXCR4/genética , Neoplasias/genética , Transdução de Sinais/genética , Prognóstico , MicroRNAs/genéticaRESUMO
Cancer metastasis is a major reason for the cancer-associated deaths and a role of long non-coding RNAs (lncRNAs) in cancer metastasis is increasingly being realized. Among the many oncogenic pathways, NF-κB signalling's involvement in cancer metastasis as a key inflammation-regulatory transcription factor has been a subject of interest for long time. Accumulating data from in vitro as well as in vivo studies along with analysis of clinical cancer tissues points to regulation of NF-κB signalling by lncRNAs with implications toward the onset of cancer metastasis. LncRNAs FOXD2-AS1, KRT19P3 and the NF-κB interacting lncRNA (NKILA) associate with lymph node metastasis and poor prognosis of individual cancers. The role of epithelial-mesenchymal transition (EMT) in cancer metastasis is well known. EMT is regulated by NF-κB and regulation of NF-κB/EMT-induced metastasis by lncRNAs remains a hot topic of research with indications for such roles of lncRNAs MALAT1, SNHG15, CRNDE and AC007271.3. Among the many lncRNAs, NKILA stands out as the most investigated lncRNA for its regulation of NF-κB. This tumor suppressive lncRNA has been reported downregulated in clinical samples representing different human cancers. Mechanistically, NKILA has been consistently shown to inhibit NF-κB activation via inhibition of IκBα phosphorylation and the resulting suppression of EMT. NKILA is also a target of natural anticancer compounds. Given the importance of NF-κB as a master regulatory transcription factor, lncRNAs, as the modulators of NF-κB signaling, can provide alternate targets for metastatic cancers with constitutively active NF-κB.
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Neoplasias , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/genética , NF-kappa B/genética , NF-kappa B/metabolismo , Transdução de Sinais , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias/genéticaRESUMO
Esophageal cancer (EC) is frequently considered a lethal malignancy and is often identified at a later stage. It is one of the major causes of cancer-related deaths globally. The conventional treatment methods like chemotherapy, radiotherapy, and surgery offer limited efficacy and poor clinical outcome with a less than 25% 5-year survival rate. The poor prognosis of EC persists despite the growth in the development of diagnostic and therapeutic modalities to treat EC. This underlines the need to elucidate the complex molecular mechanisms that drive esophageal oncogenesis. Apart from the role of the tumor microenvironment and its structural and cellular components in tumorigenesis, mounting evidence points towards the involvement of the esophageal microbiome, inflammation, and their cross-talk in promoting esophageal cancer. The current review summarizes recent research that delineates the underlying molecular mechanisms by which the microbiota and inflammation promote the pathophysiology of esophageal cancer, thus unraveling targets for potential therapeutic intervention.
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Carcinoma de Células Escamosas , Neoplasias Esofágicas , Microbiota , Carcinogênese , Carcinoma de Células Escamosas/patologia , Transformação Celular Neoplásica , Humanos , Inflamação , Microambiente TumoralRESUMO
Arsenic trioxide (ATO), an inorganic arsenical, is a toxic environmental contaminant. It is also a widely used chemical with industrial and medicinal uses. Significant public health risk exists from its intentional or accidental exposure. The pulmonary pathology of acute high dose exposure is not well defined. We developed and characterized a murine model of a single inhaled exposure to ATO, which was evaluated 24 h post-exposure. ATO caused hypoxemia as demonstrated by arterial blood-gas measurements. ATO administration caused disruption of alveolar-capillary membrane as shown by increase in total protein and IgM in the bronchoalveolar lavage fluid (BALF) supernatant and an onset of pulmonary edema. BALF of ATO-exposed mice had increased HMGB1, a damage-associated molecular pattern (DAMP) molecule, and differential cell counts revealed increased neutrophils. BALF supernatant also showed an increase in protein levels of eotaxin/CCL-11 and MCP-3/CCL-7 and a reduction in IL-10, IL-19, IFN-γ, and IL-2. In the lung of ATO-exposed mice, increased protein levels of G-CSF, CXCL-5, and CCL-11 were noted. Increased mRNA levels of TNF-a, and CCL2 in ATO-challenged lungs further supported an inflammatory pathogenesis. Neutrophils were increased in the blood of ATO-exposed animals. Pulmonary function was also evaluated using flexiVent. Consistent with an acute lung injury phenotype, respiratory and lung elastance showed significant increase in ATO-exposed mice. PV loops showed a downward shift and a decrease in inspiratory capacity in the ATO mice. Flow-volume curves showed a decrease in FEV0.1 and FEF50. These results demonstrate that inhaled ATO leads to pulmonary damage and characteristic dysfunctions resembling ARDS in humans.
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Lesão Pulmonar Aguda , Arsenicais , Humanos , Camundongos , Animais , Modelos Animais de Doenças , Pulmão/patologia , Líquido da Lavagem Broncoalveolar/químicaRESUMO
The ever-growing perception of cancer stem cells (CSCs) as a plastic state rather than a hardwired defined entity has evolved our understanding of the functional and biological plasticity of these elusive components in malignancies. Pancreatic cancer (PC), based on its biological features and clinical evolution, is a prototypical example of a CSC-driven disease. Since the discovery of pancreatic CSCs (PCSCs) in 2007, evidence has unraveled their control over many facets of the natural history of PC, including primary tumor growth, metastatic progression, disease recurrence, and acquired drug resistance. Consequently, the current near-ubiquitous treatment regimens for PC using aggressive cytotoxic agents, aimed at ''tumor debulking'' rather than eradication of CSCs, have proven ineffective in providing clinically convincing improvements in patients with this dreadful disease. Herein, we review the key hallmarks as well as the intrinsic and extrinsic resistance mechanisms of CSCs that mediate treatment failure in PC and enlist the potential CSC-targeting 'natural agents' that are gaining popularity in recent years. A better understanding of the molecular and functional landscape of PCSC-intrinsic evasion of chemotherapeutic drugs offers a facile opportunity for treating PC, an intractable cancer with a grim prognosis and in dire need of effective therapeutic advances.
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Resistencia a Medicamentos Antineoplásicos , Neoplasias Pancreáticas , Humanos , Células-Tronco Neoplásicas , Pâncreas , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , PrognósticoRESUMO
Cancer affects millions of people worldwide every year [...].
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Exossomos , Neoplasias , Humanos , Neoplasias/diagnóstico , Neoplasias/terapiaRESUMO
Exosomes, the extracellular vesicles produced in the endosomal compartments, facilitate the transportation of proteins as well as nucleic acids. Epigenetic modifications are now considered important for fine-tuning the response of cancer cells to various therapies, and the acquired resistance against targeted therapies often involves dysregulated epigenetic modifications. Depending on the constitution of their cargo, exosomes can affect several epigenetic events, thus impacting post-transcriptional regulations. Thus, a role of exosomes as facilitators of epigenetic modifications has come under increased scrutiny in recent years. Exosomes can deliver methyltransferases to recipient cells and, more importantly, non-coding RNAs, particularly microRNAs (miRNAs), represent an important exosome cargo that can affect the expression of several oncogenes and tumor suppressors, with a resulting impact on cancer therapy resistance. Exosomes often harbor other non-coding RNAs, such as long non-coding RNAs and circular RNAs that support resistance. The exosome-mediated transfer of all this cargo between cancer cells and their surrounding cells, especially tumor-associated macrophages and cancer-associated fibroblasts, has a profound effect on the sensitivity of cancer cells to several chemotherapeutics. This review focuses on the exosome-induced modulation of epigenetic events with resulting impact on sensitivity of cancer cells to various therapies, such as, tamoxifen, cisplatin, gemcitabine and tyrosine kinase inhibitors. A better understanding of the mechanisms by which exosomes can modulate response to therapy in cancer cells is critical for the development of novel therapeutic strategies to target cancer drug resistance.
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Exossomos , MicroRNAs , Neoplasias , RNA Longo não Codificante , Resistencia a Medicamentos Antineoplásicos/genética , Epigênese Genética , Exossomos/genética , Exossomos/metabolismo , MicroRNAs/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/genética , RNA Longo não Codificante/metabolismoRESUMO
Large-scale sequencing methodologies have helped us identify numerous genomic alterations and we have started to scratch the surface of many new targets for treatment of cancer and the associated predictive biomarkers. TRAIL (TNF-related apoptosis-inducing ligand) is a highly appreciated anti-cancer molecule because of its ability to selectively target cancer cells. However, confluence of information suggests that cancer cells develop resistance against TRAIL-based therapeutics. It is being realized that overexpression of anti-apoptotic proteins and inactivation of pro-apoptotic proteins significantly impairs TRAIL triggered apoptosis, particularly in clinical settings. Re-balancing of pro-and anti-apoptotic proteins and upregulation of death receptors with functionally active extrinsic and intrinsic apoptotic pathways are necessary to sensitize cancer cells to TRAIL based therapeutics. microRNAs (miRNAs) are involved in regulation of myriad of molecular processes and characterized into oncogenic and tumor suppressor miRNAs. Accumulating data has identified miRNAs which positively or negatively regulate TRAIL mediated signaling in cancer cells, helping us understand different steps at which TRAIL-mediated apoptotic signaling can be targeted. Here, we assess the status of our understanding of the mechanisms related to miRNA regulation of TRAIL mediated signaling, as well as the existing gaps therein, and discuss the challenges and opportunities that will help us get closer to personalized medicine.
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MicroRNAs/genética , Neoplasias/genética , Transdução de Sinais/genética , Ligante Indutor de Apoptose Relacionado a TNF/genética , Animais , Apoptose/genética , Humanos , Regulação para Cima/genéticaRESUMO
Despite efforts at various levels, racial health disparities still exist in cancer patients. These inequalities in incidence and/or clinical outcome can only be explained by a multitude of factors, with genetic basis being one of them. Several investigations have provided convincing evidence to support epigenetic regulation of cancer-associated genes, which results in the differential transcriptome and proteome, and may be linked to a pre-disposition of individuals of certain race/ethnicity to early or more aggressive cancers. Recent technological advancements and the ability to quickly analyze whole genome have aided in these efforts, and owing to their relatively easy detection, methylation events are much well-characterized, than the acetylation events, across human populations. The early trend of investigating a pre-determined set of genes for differential epigenetic regulation is paving way for more unbiased screening. This review summarizes our current understanding of the epigenetic events that have been tied to the racial differences in cancer incidence and mortality. A better understanding of the epigenetics of racial diversity holds promise for the design and execution of novel strategies targeting the human epigenome for reducing the disparity gaps.