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Importance: Glioblastoma is the most lethal primary brain cancer. Clinical outcomes for glioblastoma remain poor, and new treatments are needed. Objective: To investigate whether adding autologous tumor lysate-loaded dendritic cell vaccine (DCVax-L) to standard of care (SOC) extends survival among patients with glioblastoma. Design, Setting, and Participants: This phase 3, prospective, externally controlled nonrandomized trial compared overall survival (OS) in patients with newly diagnosed glioblastoma (nGBM) and recurrent glioblastoma (rGBM) treated with DCVax-L plus SOC vs contemporaneous matched external control patients treated with SOC. This international, multicenter trial was conducted at 94 sites in 4 countries from August 2007 to November 2015. Data analysis was conducted from October 2020 to September 2021. Interventions: The active treatment was DCVax-L plus SOC temozolomide. The nGBM external control patients received SOC temozolomide and placebo; the rGBM external controls received approved rGBM therapies. Main Outcomes and Measures: The primary and secondary end points compared overall survival (OS) in nGBM and rGBM, respectively, with contemporaneous matched external control populations from the control groups of other formal randomized clinical trials. Results: A total of 331 patients were enrolled in the trial, with 232 randomized to the DCVax-L group and 99 to the placebo group. Median OS (mOS) for the 232 patients with nGBM receiving DCVax-L was 19.3 (95% CI, 17.5-21.3) months from randomization (22.4 months from surgery) vs 16.5 (95% CI, 16.0-17.5) months from randomization in control patients (HR = 0.80; 98% CI, 0.00-0.94; P = .002). Survival at 48 months from randomization was 15.7% vs 9.9%, and at 60 months, it was 13.0% vs 5.7%. For 64 patients with rGBM receiving DCVax-L, mOS was 13.2 (95% CI, 9.7-16.8) months from relapse vs 7.8 (95% CI, 7.2-8.2) months among control patients (HR, 0.58; 98% CI, 0.00-0.76; P < .001). Survival at 24 and 30 months after recurrence was 20.7% vs 9.6% and 11.1% vs 5.1%, respectively. Survival was improved in patients with nGBM with methylated MGMT receiving DCVax-L compared with external control patients (HR, 0.74; 98% CI, 0.55-1.00; P = .03). Conclusions and Relevance: In this study, adding DCVax-L to SOC resulted in clinically meaningful and statistically significant extension of survival for patients with both nGBM and rGBM compared with contemporaneous, matched external controls who received SOC alone. Trial Registration: ClinicalTrials.gov Identifier: NCT00045968.
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Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/tratamiento farmacológico , Glioblastoma/patología , Temozolomida/uso terapéutico , Estudios Prospectivos , Neoplasias Encefálicas/patología , Recurrencia , Células Dendríticas/patología , VacunaciónRESUMEN
BACKGROUND: Choroid plexus tumors are rare neoplasms that are typically found in the lateral ventricles. They have infrequently been reported in the third ventricle, and treatment strategies have varied. OBSERVATIONS: The authors described a 6-month-old patient who presented with irritability and hypotonia. The patient was found to have a large tumor in the third ventricle with obstructive hydrocephalus. Preoperative angiography revealed a feeding artery from the right medial posterior choroidal artery (MPChA). The feeding artery was effectively embolized, and the patient subsequently received open resection of the tumor. Pathology revealed features consistent with atypical choroid plexus papilloma (CPP). LESSONS: Choroid plexus tumors are often hypervascular, which can often make gross total resection (GTR) difficult. Preoperative angiography of tumors identifies feeding vessels, and embolization has the potential to decrease perioperative blood loss and allow for a higher GTR rate. Third ventricular CPPs appear to invariably receive vascular supply from the MPChA, arising from the right posterior cerebral artery. Embolization followed by resection of a choroid plexus tumor in the third ventricle is an effective treatment strategy.
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Rising concerns about the short- and long-term detrimental consequences of administration of conventional pharmacopeia are fueling the search for alternative, complementary, personalized, and comprehensive approaches to human healthcare. Qigong, a form of Traditional Chinese Medicine, represents a viable alternative approach. Here, we started with the practical, philosophical, and psychological background of Ki (in Japanese) or Qi (in Chinese) and their relationship to Qigong theory and clinical application. Noting the drawbacks of the current state of Qigong clinic, herein we propose that to manage the unique aspects of the Eastern 'non-linearity' and 'holistic' approach, it needs to be integrated with the Western "linearity" "one-direction" approach. This is done through developing the concepts of "Qigong breathing signatures," which can define our life breathing patterns associated with diseases using machine learning technology. We predict that this can be achieved by establishing an artificial intelligence (AI)-Medicine training camp of databases, which will integrate Qigong-like breathing patterns with different pathologies unique to individuals. Such an integrated connection will allow the AI-Medicine algorithm to identify breathing patterns and guide medical intervention. This unique view of potentially connecting Eastern Medicine and Western Technology can further add a novel insight to our current understanding of both Western and Eastern medicine, thereby establishing a vitality score index (VSI) that can predict the outcomes of lifestyle behaviors and medical conditions.
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INTRODUCTION: Preterm infants require intravenous (IV) access for administration of medications, IV fluids, and parenteral nutrition. The scalp is a common site for obtaining IV access, and in children with hydrocephalus or wide fontanelles and sutures, there is a high probability of penetrating the meninges and brain matter with the scalp IV needle. If this penetration occurs and remains unnoticed, the contents of the IV infusion can infiltrate into the brain and cause severe brain damage. CASE PRESENTATION: A 3-day-old female neonate, born with myelomeningocele, was receiving total parenteral nutrition through a scalp-vein IV. She experienced a sudden increase in head circumference, a bulging fontanelle, and respiratory distress. Magnetic resonance images demonstrated subdural fluid collection, and the patient underwent emergency surgery. The dura, when opened, exuded milky-white fluid consistent in color with parenteral nutrition. Postoperative imaging showed a parenchymal abnormality caused by the intracranial and intraparenchymal infusion of parenteral nutrition. Four years later, the child had a shunt and had mild cognitive impairment. DISCUSSION: In cases of accidental intracranial administration of parenteral nutrition, we recommend that aggressive therapy be pursued to minimize the risks of developing comorbidities such as meningitis and to allow for maximal functional recovery.
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Lesiones Encefálicas/etiología , Catéteres/efectos adversos , Meningomielocele/terapia , Nutrición Parenteral/efectos adversos , Nutrición Parenteral/instrumentación , Cuero Cabelludo , Encéfalo/diagnóstico por imagen , Encéfalo/cirugía , Lesiones Encefálicas/diagnóstico por imagen , Lesiones Encefálicas/cirugía , Disfunción Cognitiva/etiología , Diagnóstico por Imagen , Femenino , Humanos , Hidrocefalia/diagnóstico por imagen , Hidrocefalia/etiología , Hidrocefalia/cirugía , Recién Nacido , Infusiones Intravenosas , Meninges/lesiones , Meningomielocele/complicaciones , Nutrición Parenteral/métodos , Complicaciones Posoperatorias/diagnóstico por imagen , Complicaciones Posoperatorias/cirugía , Índice de Severidad de la Enfermedad , Derivación VentriculoperitonealRESUMEN
The clinical benefits of the MammaPrint® signature for breast cancer is well documented; however, how these genes are related to cell cycle perturbation have not been well determined. Our single-cell transcriptome mapping (algorithm) provides details into the fine perturbation of all individual genes during a cell cycle, providing a view of the cell-cycle-phase specific landscape of any given human genes. Specifically, we identified that 38 out of the 70 (54%) MammaPrint® signature genes are perturbated to a specific phase of the cell cycle. The MammaPrint® signature panel derived its clinical prognosis power from measuring the cell cycle activity of specific breast cancer samples. Such cell cycle phase index of the MammaPrint® signature suggested that measurement of the cell cycle index from tumors could be developed into a prognosis tool for various types of cancer beyond breast cancer, potentially improving therapy through targeting a specific phase of the cell cycle of cancer cells.
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Following publication of the original article [1], the authors reported an error in the spelling of one of the author names. In this Correction the incorrect and correct author names are indicated and the author name has been updated in the original publication. The authors also reported an error in the Methods section of the original article. In this Correction the incorrect and correct versions of the affected sentence are indicated. The original article has not been updated with regards to the error in the Methods section.
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Glioblastoma multiforme (GBM) remains an incurable brain tumor. The highly malignant behavior of GBM may, in part, be attributed to its intraclonal genetic and phenotypic diversity (subclonal evolution). Identifying the molecular pathways driving GBM relapse may provide novel, actionable targets for personalized diagnosis, characterization of prognosis and improvement of precision therapy. We screened single-cell transcriptomes, namely RNA-seq data of primary and relapsed GBM tumors from a patient, to define the molecular profile of relapse. Characterization of hundreds of individual tumor cells identified three mutated genes within single cells, involved in the RAS/GEF GTP-dependent signaling pathway. The identified molecular pathway was further verified by meta-analysis of RNA-seq data from more than 3000 patients. This study showed that single-cell molecular analysis overcomes the inherent heterogeneity of bulk tumors with respect to defining tumor subclonal evolution relevant to GBM relapse.
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Neoplasias Encefálicas/patología , Glioblastoma/patología , Neoplasias Encefálicas/genética , Glioblastoma/genética , Humanos , Masculino , Metaanálisis como Asunto , Mutación/genética , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/patología , Pronóstico , Recurrencia , Transducción de Señal/fisiología , Análisis de la Célula Individual/métodosRESUMEN
BACKGROUND: Standard therapy for glioblastoma includes surgery, radiotherapy, and temozolomide. This Phase 3 trial evaluates the addition of an autologous tumor lysate-pulsed dendritic cell vaccine (DCVax®-L) to standard therapy for newly diagnosed glioblastoma. METHODS: After surgery and chemoradiotherapy, patients were randomized (2:1) to receive temozolomide plus DCVax-L (n = 232) or temozolomide and placebo (n = 99). Following recurrence, all patients were allowed to receive DCVax-L, without unblinding. The primary endpoint was progression free survival (PFS); the secondary endpoint was overall survival (OS). RESULTS: For the intent-to-treat (ITT) population (n = 331), median OS (mOS) was 23.1 months from surgery. Because of the cross-over trial design, nearly 90% of the ITT population received DCVax-L. For patients with methylated MGMT (n = 131), mOS was 34.7 months from surgery, with a 3-year survival of 46.4%. As of this analysis, 223 patients are ≥ 30 months past their surgery date; 67 of these (30.0%) have lived ≥ 30 months and have a Kaplan-Meier (KM)-derived mOS of 46.5 months. 182 patients are ≥ 36 months past surgery; 44 of these (24.2%) have lived ≥ 36 months and have a KM-derived mOS of 88.2 months. A population of extended survivors (n = 100) with mOS of 40.5 months, not explained by known prognostic factors, will be analyzed further. Only 2.1% of ITT patients (n = 7) had a grade 3 or 4 adverse event that was deemed at least possibly related to the vaccine. Overall adverse events with DCVax were comparable to standard therapy alone. CONCLUSIONS: Addition of DCVax-L to standard therapy is feasible and safe in glioblastoma patients, and may extend survival. Trial registration Funded by Northwest Biotherapeutics; Clinicaltrials.gov number: NCT00045968; https://clinicaltrials.gov/ct2/show/NCT00045968?term=NCT00045968&rank=1 ; initially registered 19 September 2002.
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Neoplasias Encefálicas/inmunología , Neoplasias Encefálicas/terapia , Vacunas contra el Cáncer/inmunología , Células Dendríticas/inmunología , Glioblastoma/inmunología , Glioblastoma/terapia , Adulto , Anciano , Neoplasias Encefálicas/diagnóstico , Vacunas contra el Cáncer/efectos adversos , Determinación de Punto Final , Femenino , Glioblastoma/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Análisis de Supervivencia , Resultado del Tratamiento , Adulto JovenRESUMEN
Cytogenetic alterations form the basis for risk stratification for multiple myeloma (MM) and guide the selection of therapy; however, current pathology assays performed on bone marrow samples can produce false-negatives due to the unpredictable distribution and rarity of MM cells. Here, we report on a microfluidic device used to facilitate CD45 depletion to enhance the detection of cytogenetic alterations in plasma cells (PCs). Bone marrow samples from 48 patients with MM were each divided into two aliquots. One aliquot was subjected to classic flow cytometry and fluorescent in situ hybridization (FISH). The other first went through CD45+ cell depletion, further enriched by microfluidic size selection. The enriched samples were then analyzed using flow cytometry and FISH and compared to those analyzed using the classic method only. Unlike the traditional method, the microfluidic device removed the CD45+ leukocytes and specifically selected PCs from the remaining white blood cells. Therefore, the microfluidic method (MF-CD45-TACs) significantly increased the percentage of CD38+ /CD138+ cells to 37.7 ± 20.4% (P < 0.001) from 10.3 ± 8.5% in bone marrow. After the MF-CD45-TAC enrichment, the detection rate of IgH rearrangement, del(13q14), del(17p), and 1q21 gains, rose to 56.3% (P < 0.001), 37.5% (P < 0.001), 22.9% (P < 0.001), and 41.7% (P = 0.001), respectively; all rates of detection were significantly increased compared to the classically analyzed samples. In this clinical trial, this microfluidic-assisted assay provided a precise detection of cytogenetic alterations in PCs and improved clinical outcomes.
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Microfluídica/métodos , Mieloma Múltiple/patología , Células Plasmáticas/patología , Adulto , Anciano , Línea Celular Tumoral , Femenino , Humanos , Antígenos Comunes de Leucocito/metabolismo , Masculino , Persona de Mediana Edad , Medición de Riesgo , Resultado del TratamientoRESUMEN
BACKGROUND: Targeting the tumor microenvironment (TME) through which cancer stem cells (CSCs) crosstalk for cancer initiation and progression, may open new treatments different from those centered on the original hallmarks of cancer genetics thereby implying a new approach for suppression of TME driven activation of CSCs. Cancer is dynamic, heterogeneous, evolving with the TME and can be influenced by tissue-specific elasticity. One of the mediators and modulators of the crosstalk between CSCs and mechanical forces is miRNA, which can be developmentally regulated, in a tissue- and cellspecific manner. OBJECTIVE: Here, based on our previous data, we provide a framework through which such gene expression changes in response to external mechanical forces can be understood during cancer progression. Recognizing the ways mechanical forces regulate and affect intracellular signals with applications in cancer stem cell biology. Such TME-targeted pathways shed new light on strategies for attacking cancer stem cells with fewer side effects than traditional gene-based treatments for cancer, requiring a "watchand- wait" approach. We attempt to address both normal brain microenvironment and tumor microenvironment as both works together, intertwining in pathology and physiology - a balance that needs to be maintained for the "watch-and-wait" approach to cancer. CONCLUSION: This review connected the subjects of tissue elasticity, tumor microenvironment, epigenetic of miRNAs, and stem-cell biology that are very relevant in cancer research and therapy. It attempts to unify apparently separate entities in a complex biological web, network, and system in a realistic and practical manner, i.e., to bridge basic research with clinical application.
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Regulación Neoplásica de la Expresión Génica/genética , MicroARNs/genética , Neoplasias/genética , Microambiente Tumoral/genética , Animales , Elasticidad/fisiología , Humanos , Neoplasias/patología , Células Madre Neoplásicas/citologíaRESUMEN
BACKGROUND: The tumor microenvironment consists of both physical and chemical factors. Tissue elasticity is one physical factor contributing to the microenvironment of tumor cells. To test the importance of tissue elasticity in cell culture, primitive neuroectodermal tumor (PNET) stem cells were cultured on soft polyacrylamide (PAA) hydrogel plates that mimics the elasticity of brain tissue compared with PNET on standard polystyrene (PS) plates. We report the molecular profiles of PNET grown on either PAA or PS. METHODOLOGY/PRINCIPAL FINDINGS: A whole-genome microarray profile of transcriptional expression between the two culture conditions was performed as a way to probe effects of substrate on cell behavior in culture. The results showed more genes downregulated on PAA compared to PS. This led us to propose microRNA (miRNA) silencing as a potential mechanism for downregulation. Bioinformatic analysis predicted a greater number of miRNA binding sites from the 3' UTR of downregulated genes and identified as specific miRNA binding sites that were enriched when cells were grown on PAA-this supports the hypothesis that tissue elasticity plays a role in influencing miRNA expression. Thus, Dicer was examined to determine if miRNA processing was affected by tissue elasticity. Dicer genes were downregulated on PAA and had multiple predicted miRNA binding sites in its 3' UTR that matched the miRNA binding sites found enriched on PAA. Many differentially regulated genes were found to be present on PS but downregulated on PAA were mapped onto intron sequences. This suggests expression of alternative polyadenylation sites within intron regions that provide alternative 3' UTRs and alternative miRNA binding sites. This results in tissue specific transcriptional downregulation of mRNA in humans by miRNA. We propose a mechanism, driven by the physical characteristics of the microenvironment by which downregulation of genes occur. We found that tissue elasticity-mediated cytokines (TGFß2 and TNFα) signaling affect expression of ECM proteins. CONCLUSIONS: Our results suggest that tissue elasticity plays important roles in miRNA expression, which, in turn, regulate tumor growth or tumorigenicity.
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Biomarcadores de Tumor/metabolismo , Elasticidad , Regulación Neoplásica de la Expresión Génica , Células Madre Neoplásicas/metabolismo , Tumores Neuroectodérmicos Primitivos/metabolismo , Regiones no Traducidas 3' , Resinas Acrílicas/farmacología , Biomarcadores de Tumor/genética , Células Cultivadas , Niño , ARN Helicasas DEAD-box/genética , ARN Helicasas DEAD-box/metabolismo , Proteínas de la Matriz Extracelular/genética , Proteínas de la Matriz Extracelular/metabolismo , Femenino , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacología , Intrones , Células Madre Neoplásicas/efectos de los fármacos , Poliadenilación , Poliestirenos/farmacología , Interferencia de ARN , Ribonucleasa III/genética , Ribonucleasa III/metabolismo , Transcripción Genética , Factor de Crecimiento Transformador beta2/genética , Factor de Crecimiento Transformador beta2/metabolismo , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
The US National Cancer Institute (NCI) and the National Human Genome Research Institute (NHGRI) created the Cancer Genome Atlas (TCGA) Project in 2006. The TCGA's goal was to sequence the genomes of 10,000 tumors to identify common genetic changes among different types of tumors for developing genetic-based treatments. TCGA offered great potential for cancer patients, but in reality has little impact on clinical applications. Recent reports place the past TCGA approach of testing a small tumor mass at a single time-point at a crossroads. This crossroads presents us with the conundrum of whether we should sequence more tumors or obtain multiple biopsies from each individual tumor at different time points. Sequencing more tumors with the past TCGA approach of single time-point sampling can neither capture the heterogeneity between different parts of the same tumor nor catch the heterogeneity that occurs as a function of time, error rates, and random drift. Obtaining multiple biopsies from each individual tumor presents multiple logistical and financial challenges. Here, we review current literature and rethink the utility and application of the TCGA approach. We discuss that the TCGA-led catalogue may provide insights into studying the functional significance of oncogenic genes in reference to non-cancer genetic background. Different methods to enhance identifying cancer targets, such as single cell technology, real time imaging of cancer cells with a biological global positioning system, and cross-referencing big data sets, are offered as ways to address sampling discrepancies in the face of tumor heterogeneity. We predict that TCGA landmarks may prove far more useful for cancer prevention than for cancer diagnosis and treatment when considering the effect of non-cancer genes and the normal genetic background on tumor microenvironment. Cancer prevention can be better realized once we understand how therapy affects the genetic makeup of cancer over time in a clinical setting. This may help create novel therapies for gene mutations that arise during a tumor's evolution from the selection pressure of treatment.
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The treatment of malignant brain tumors remains a challenge. Stem cell technology has been applied in the treatment of brain tumors largely because of the ability of some stem cells to infiltrate into regions within the brain where tumor cells migrate as shown in preclinical studies. However, not all of these efforts can translate in the effective treatment that improves the quality of life for patients. Here, we perform a literature review to identify the problems in the field. Given the lack of efficacy of most stem cell-based agents used in the treatment of malignant brain tumors, we found that stem cell distribution (i.e., only a fraction of stem cells applied capable of targeting tumors) are among the limiting factors. We provide guidelines for potential improvements in stem cell distribution. Specifically, we use an engineered tissue graft platform that replicates the in vivo microenvironment, and provide our data to validate that this culture platform is viable for producing stem cells that have better stem cell distribution than with the Petri dish culture system.
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BACKGROUND: The cancer stem cell (CSC) hypothesis posits that deregulated neural stem cells (NSCs) form the basis of brain tumors such as glioblastoma multiforme (GBM). GBM, however, usually forms in the cerebral white matter while normal NSCs reside in subventricular and hippocampal regions. We attempted to characterize CSCs from a rare form of glioblastoma multiforme involving the neurogenic ventricular wall. METHODS: We described isolating CSCs from a GBM involving the lateral ventricles and characterized these cells with in vitro molecular biomarker profiling, cellular behavior, ex vivo and in vivo techniques. RESULTS: The patient's MRI revealed a heterogeneous mass with associated edema, involving the left subventricular zone. Histological examination of the tumor established it as being a high-grade glial neoplasm, characterized by polygonal and fusiform cells with marked nuclear atypia, amphophilic cytoplasm, prominent nucleoli, frequent mitotic figures, irregular zones of necrosis and vascular hyperplasia. Recurrence of the tumor occurred shortly after the surgical resection. CD133-positive cells, isolated from the tumor, expressed stem cell markers including nestin, CD133, Ki67, Sox2, EFNB1, EFNB2, EFNB3, Cav-1, Musashi, Nucleostemin, Notch 2, Notch 4, and Pax6. Biomarkers expressed in differentiated cells included Cathepsin L, Cathepsin B, Mucin18, Mucin24, c-Myc, NSE, and TIMP1. Expression of unique cancer-related transcripts in these CD133-positive cells, such as caveolin-1 and -2, do not appear to have been previously reported in the literature. Ex vivo organotypic brain slice co-culture showed that the CD133+ cells behaved like tumor cells. The CD133-positive cells also induced tumor formation when they were stereotactically transplanted into the brains of the immune-deficient NOD/SCID mice. CONCLUSIONS: This brain tumor involving the neurogenic lateral ventricular wall was comprised of tumor-forming, CD133-positive cancer stem cells, which are likely the driving force for the rapid recurrence of the tumor in the patient.
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This editorial addresses the current challenges and future directions in the use of stem cells as an approach for treating amyotrophic lateral sclerosis. A wide variety of literature has been reviewed to enlighten the reader on the many facets of stem cell research that are important to consider before using them for a cell based therapy.
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Recent studies have shown that treatments involving injection of stem cells into animals with damaged cardiac tissue result in improved cardiac functionality. Clinical trials have reported conflicting results concerning the recellularization of post-infarct collagen scars. No clear mechanism has so far emerged to fully explain how injected stem cells, specifically the commonly used mesenchymal stem cells (MSC) and endothelial precursor cells (EPC), help heal a damaged heart. Clearly, these injected stem cells must survive and thrive in the hypoxic environment that results after injury for any significant repair to occur. Here we discuss how ischemic preconditioning may lead to increased tolerance of stem cells to these harsh conditions and increase their survival and clinical potential after injection. As injected cells must reach the site in numbers large enough for repair to be functionally significant, homing mechanisms involved in stem cell migration are also discussed. We review the mechanisms of action stem cells may employ once they arrive at their target destination. These possible mechanisms include that the injected stem cells (1) secrete growth factors, (2) differentiate into cardiomyocytes to recellularize damaged tissue and strengthen the post-infarct scar, (3) transdifferentiate the host cells into cardiomyocytes, and (4) induce neovascularization. Finally, we discuss that tissue engineering may provide a standardized platform technology to produce clinically applicable stem cell products with these desired mechanistic capacities.
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Citocinas/inmunología , Trasplante de Células Madre Mesenquimatosas , Isquemia Miocárdica/terapia , Células Madre/fisiología , Animales , Apoptosis , Movimiento Celular , Supervivencia de Injerto , Humanos , Inmunidad Innata , Isquemia Miocárdica/patología , Neovascularización Fisiológica , Transducción de Señal/inmunologíaRESUMEN
Increased evidence shows that normal stem cells may contribute to cancer development and progression by acting as cancer-initiating cells through their interactions with abnormal environmental elements. We postulate that normal stem cells and cancer stem cells (CSC) possess similar mechanisms of self-renewal and differentiation. CSC can be the key to the elaboration of anti-cancer-based therapy. In this article, we focus on a controversial new theme relating to CSC. Tumorigenesis may have a critical stage characterized as a "therapeutic window", which can be identified by association of molecular, biochemical and biological events. Identifying such a stage can allow the production of more effective therapies (e.g. manipulated stem cells) to treat several cancers. More importantly, confirming the existence of a similar therapeutic window during the conversion of normal stem cells to malignant CSC may lead to targeted therapy specifically against CSC. This conversion information may be derived from investigating the biological behaviour of both normal stem cells and cancerous stem cells. Currently, there is little knowledge about the cellular and molecular mechanisms that govern the initiation and maintenance of CSC. Studies on co-evolution and interdependence of cancer with normal tissues may lead to a useful treatment paradigm of cancer. The crosstalk between normal stem cells and cancer formation may converge developmental stages of different types of stem cells (e.g. normal stem cells, CSC and embryonic stem cells). The differential studies of the convergence may result in novel therapies for treating cancers.