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1.
Antibiotics (Basel) ; 13(3)2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38534648

RESUMO

Antibiotic overuse and the resulting antimicrobial resistance pose significant global public health challenges, providing an avenue for opportunistic pathogens like Acinetobacter baumannii to thrive. This study will report the trends of Acinetobacter baumannii antimicrobial resistance patterns at the Hospital Teodoro Maldonado Carbo, Ecuador. An observational, analytical, longitudinal, and prospective study was conducted involving patients diagnosed with hospital-acquired infections. Antimicrobial susceptibility testing was performed, followed by molecular analysis of carbapenemase genes in Acinetobacter baumannii isolates. We included 180 patients aged from 16 to 93 years. The hospital mortality rate was 63/180 (35%). Invasive mechanical ventilation (IMV) was indicated in 91/180 patients (50.4%). The overall survival (OS) rate in patients on IMV was 49.5% (45/91), with a median survival of 65 days. The OS rate in patients not on IMV was 80.9% (72/89), with a median survival of 106 days (HR 2.094; 95% CI 1.174-3.737; p = 0.012). From multivariate analysis, we conclude that ventilator-associated pneumonia is the most related factor to OS.

2.
Expert Rev Clin Pharmacol ; 17(4): 323-347, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38413373

RESUMO

INTRODUCTION: Treatment resistance poses a significant obstacle in oncology, especially in biliary tract cancer (BTC) and pancreatic cancer (PC). Current therapeutic options include chemotherapy, targeted therapy, and immunotherapy. Resistance to these treatments may arise due to diverse molecular mechanisms, such as genetic and epigenetic modifications, altered drug metabolism and efflux, and changes in the tumor microenvironment. Identifying and overcoming these mechanisms is a major focus of research: strategies being explored include combination therapies, modulation of the tumor microenvironment, and personalized approaches. AREAS COVERED: We provide a current overview and discussion of the most relevant mechanisms of resistance to chemotherapy, target therapy, and immunotherapy in both BTC and PC. Furthermore, we compare the different strategies that are being implemented to overcome these obstacles. EXPERT OPINION: So far there is no unified theory on drug resistance and progress is limited. To overcome this issue, individualized patient approaches, possibly through liquid biopsies or single-cell transcriptome studies, are suggested, along with the potential use of artificial intelligence, to guide effective treatment strategies. Furthermore, we provide insights into what we consider the most promising areas of research, and we speculate on the future of managing treatment resistance to improve patient outcomes.


Assuntos
Neoplasias do Sistema Biliar , Neoplasias Pancreáticas , Farmacologia Clínica , Humanos , Inteligência Artificial , Neoplasias do Sistema Biliar/tratamento farmacológico , Neoplasias do Sistema Biliar/genética , Neoplasias do Sistema Biliar/patologia , Imunoterapia , Terapia Combinada , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Terapia de Alvo Molecular , Microambiente Tumoral
4.
Cancers (Basel) ; 15(14)2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37509327

RESUMO

Malignant melanoma (MM) can spread to other organs and is resistant in part due to the presence of cancer stem cell subpopulations (CSCs). While a controversial high dose of interferon-alpha (IFN-α) has been used to treat non-metastatic high-risk melanoma, it comes with undesirable side effects. In this study, we evaluated the effect of low and high doses of IFN-α on CSCs by analyzing ALDH activity, side population and specific surface markers in established and patient-derived primary cell lines. We also assessed the clonogenicity, migration and tumor initiation capacities of IFN-α treated CSCs. Additionally, we investigated genomic modulations related to stemness properties using microRNA sequencing and microarrays. The effect of IFN-α on CSCs-derived exosomes was also analyzed using NanoSight and liquid chromatography (LC-HRMS)-based metabolomic analysis, among others. Our results showed that even low doses of IFN-α reduced CSC formation and stemness properties, and led to a significant decrease in the ability to form tumors in mice xenotransplants. IFN-α also modulated the expression of genes and microRNAs involved in several cancer processes and metabolomics of released exosomes. Our work suggests the utility of low doses of interferon, combined with the analysis of metabolic biomarkers, as a potential clinical approach against the aggressiveness of CSCs in melanoma.

5.
Front Cell Dev Biol ; 11: 1148768, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37009489

RESUMO

Cardiovascular diseases (CVD) are the leading causes of death and disability in the world. Among all CVD, the most common is coronary artery disease (CAD). CAD results from the complications promoted by atherosclerosis, which is characterized by the accumulation of atherosclerotic plaques that limit and block the blood flow of the arteries involved in heart oxygenation. Atherosclerotic disease is usually treated by stents implantation and angioplasty, but these surgical interventions also favour thrombosis and restenosis which often lead to device failure. Hence, efficient and long-lasting therapeutic options that are easily accessible to patients are in high demand. Advanced technologies including nanotechnology or vascular tissue engineering may provide promising solutions for CVD. Moreover, advances in the understanding of the biological processes underlying atherosclerosis can lead to a significant improvement in the management of CVD and even to the development of novel efficient drugs. To note, over the last years, the observation that inflammation leads to atherosclerosis has gained interest providing a link between atheroma formation and oncogenesis. Here, we have focused on the description of the available therapy for atherosclerosis, including surgical treatment and experimental treatment, the mechanisms of atheroma formation, and possible novel therapeutic candidates such as the use of anti-inflammatory treatments to reduce CVD.

6.
Int J Mol Sci ; 24(5)2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36901917

RESUMO

The acquisition of resistance to traditional chemotherapy and the chemoresistant metastatic relapse of minimal residual disease both play a key role in the treatment failure and poor prognosis of cancer. Understanding how cancer cells overcome chemotherapy-induced cell death is critical to improve patient survival rate. Here, we briefly describe the technical approach directed at obtaining chemoresistant cell lines and we will focus on the main defense mechanisms against common chemotherapy triggers by tumor cells. Such as, the alteration of drug influx/efflux, the enhancement of drug metabolic neutralization, the improvement of DNA-repair mechanisms, the inhibition of apoptosis-related cell death, and the role of p53 and reactive oxygen species (ROS) levels in chemoresistance. Furthermore, we will focus on cancer stem cells (CSCs), the cell population that subsists after chemotherapy, increasing drug resistance by different processes such as epithelial-mesenchymal transition (EMT), an enhanced DNA repair machinery, and the capacity to avoid apoptosis mediated by BCL2 family proteins, such as BCL-XL, and the flexibility of their metabolism. Finally, we will review the latest approaches aimed at decreasing CSCs. Nevertheless, the development of long-term therapies to manage and control CSCs populations within the tumors is still necessary.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Recidiva Local de Neoplasia , Humanos , Recidiva Local de Neoplasia/metabolismo , Apoptose , Transição Epitelial-Mesenquimal , Células-Tronco Neoplásicas/metabolismo
7.
Int J Mol Sci ; 24(2)2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36674737

RESUMO

In general, the risk of being diagnosed with cancer increases with age; however, the development of estrogen-receptor-positive (ER+) cancer types in women are more closely related to menopausal status than age. In fact, the general risk factors for cancer development, such as obesity-induced inflammation, show differences in their association with ER+ cancer risk in pre- and postmenopausal women. Here, we tested the role of the principal estrogens in the bloodstream before and after menopause, estradiol (E2) and estrone (E1), respectively, on inflammation, epithelial-to-mesenchymal transition (EMT) and cancer stem cell enrichment in the human ER+ cervical cancer cell line HeLa. Our results demonstrate that E1, contrary to E2, is pro-inflammatory, increases embryonic stem-transcription factors (ES-TFs) expression and induces EMT in ER+ HeLa cells. Moreover, we observed that high intratumoural expression levels of 17ß-Hydroxysteroid dehydrogenase (HSD17B) isoforms involved in E1 synthesis is a poor prognosis factor, while overexpression of E2-synthetizing HSD17B isoforms is associated with a better outcome, for patients diagnosed with ER+ ovarian and uterine corpus carcinomas. This work demonstrates that E1 and E2 have different biological functions in ER+ gynaecologic cancers. These results open a new line of research in the study of ER+ cancer subtypes, highlighting the potential key oncogenic role of E1 and HSD17B E1-synthesizing enzymes in the development and progression of these diseases.


Assuntos
Estrona , Neoplasias , Humanos , Feminino , Estrona/metabolismo , Estradiol/metabolismo , NF-kappa B , Células HeLa , Inflamação
8.
Int J Mol Sci ; 23(24)2022 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-36555218

RESUMO

Tumours are complex systems with dynamic interactions between tumour cells, non-tumour cells, and extracellular components that comprise the tumour microenvironment (TME). The majority of TME's cells are cancer-associated fibroblasts (CAFs), which are crucial in extracellular matrix (ECM) construction, tumour metabolism, immunology, adaptive chemoresistance, and tumour cell motility. CAF subtypes have been identified based on the expression of protein markers. CAFs may act as promoters or suppressors in tumour cells depending on a variety of factors, including cancer stage. Indeed, CAFs have been shown to promote tumour growth, survival and spread, and secretome changes, but they can also slow tumourigenesis at an early stage through mechanisms that are still poorly understood. Stromal-cancer interactions are governed by a variety of soluble factors that determine the outcome of the tumourigenic process. Cancer cells release factors that enhance the ability of fibroblasts to secrete multiple tumour-promoting chemokines, acting on malignant cells to promote proliferation, migration, and invasion. This crosstalk between CAFs and tumour cells has given new prominence to the stromal cells, from being considered as mere physical support to becoming key players in the tumour process. Here, we focus on the concept of cancer as a non-healing wound and the relevance of chronic inflammation to tumour initiation. In addition, we review CAFs heterogeneous origins and markers together with the potential therapeutic implications of CAFs "re-education" and/or targeting tumour progression inhibition.


Assuntos
Fibroblastos Associados a Câncer , Neoplasias , Humanos , Neoplasias/metabolismo , Fibroblastos , Fibroblastos Associados a Câncer/metabolismo , Carcinogênese/metabolismo , Transformação Celular Neoplásica/metabolismo , Microambiente Tumoral
9.
Drug Resist Updat ; 64: 100864, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36115181

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) has one of the highest incidence/death ratios among all neoplasms due to its late diagnosis and dominant chemoresistance. Most PDAC patients present with an advanced disease characterized by a multifactorial, inherent and acquired resistance to current anticancer treatments. This remarkable chemoresistance has been ascribed to several PDAC features including the genetic landscape, metabolic alterations, and a heterogeneous tumor microenvironment that is characterized by dense fibrosis, and a cellular contexture including functionally distinct subclasses of cancer-associated fibroblasts, immune suppressive cells, but also a number of bacteria, shaping a specific tumor microbiome microenvironment. Thus, recent studies prompted the emergence of a new research avenue, by describing the role of the microbiome in gemcitabine resistance, while next-generation-sequencing analyses identified a specific microbiome in different tumors, including PDAC. Functionally, the contribution of these microbes to PDAC chemoresistance is only beginning to be explored. Here we provide an overview of the studies demonstrating that bacteria have the capacity to metabolically transform and hence inactivate anticancer drugs, as exemplified by the inhibition of the efficacy of 10 out of 30 chemotherapeutics by Escherichia coli. Moreover, a number of bacteria modulate specific oncogenic pathways, such as Fusobacterium nucleatum, affecting autophagy and apoptosis induction by 5-fluorouracil and oxaliplatin. We hypothesize that improved understanding of how chemoresistance is driven by bacteria could enhance the efficacy of current treatments, and discuss the potential of microbiome modulation and targeted therapeutic approaches as well as the need for more reliable models and biomarkers to translate the findings of preclinical/translational research to the clinical setting, and ultimately overcome PDAC chemoresistance, hence improving clinical outcome.


Assuntos
Antineoplásicos , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Fluoruracila/farmacologia , Fluoruracila/uso terapêutico , Humanos , Oxaliplatina/farmacologia , Oxaliplatina/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Microambiente Tumoral , Neoplasias Pancreáticas
10.
Int J Mol Sci ; 23(15)2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35955853

RESUMO

The increase in cancer incidences shows that there is a need to better understand tumour heterogeneity to achieve efficient treatments. Interestingly, there are several common features among almost all types of cancers, with chronic inflammation induction and deaminase dysfunctions singled out. Deaminases are a family of enzymes with nucleotide-editing capacity, which are classified into two main groups: DNA-based and RNA-based. Remarkably, a close relationship between inflammation and the dysregulation of these molecules has been widely documented, which may explain the characteristic intratumor heterogeneity, both at DNA and transcriptional levels. Indeed, heterogeneity in cancer makes it difficult to establish a unique tumour progression model. Currently, there are three main cancer models-stochastic, hierarchic, and dynamic-although there is no consensus on which one better resembles cancer biology because they are usually overly simplified. Here, to accurately explain tumour progression, we propose interactions among chronic inflammation, deaminases dysregulation, intratumor genetic heterogeneity, cancer phenotypic plasticity, and even the previously proposed appearance of cancer stem-like cell populations in the edges of advanced solid tumour masses (instead of being the cells of origin of primary malignancies). The new tumour development model proposed in this study does not contradict previously accepted models and it may open up a window to interesting therapeutic approaches.


Assuntos
Neoplasias , Citidina Desaminase/genética , DNA/metabolismo , Humanos , Inflamação , Neoplasias/genética , Neoplasias/patologia , RNA/metabolismo , Edição de RNA
11.
J Exp Clin Cancer Res ; 40(1): 217, 2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34183054

RESUMO

It has been well documented that the tumor microenvironment (TME) plays a key role in the promotion of drug resistance, the support of tumor progression, invasiveness, metastasis, and even the maintenance of a cancer stem-like phenotype. Here, we reviewed TME formation presenting it as a reflection of a tumor's own organization during the different stages of tumor development. Interestingly, functionally different groups of stromal cells seem to have specific spatial distributions within the TME that change as the tumor evolves into advanced stage progression which correlates with the fact that cancer stem-like cells (CSCs) are located in the edges of solid tumor masses in advanced tumors.We also focus on the continuos feedback that is established between a tumor and its surroundings. The "talk" between tumor mass cells and TME stromal cells, marks the evolution of both interlocuting cell types. For instance, the metabolic and functional transformations that stromal cells undergo due to tumor corrupting activity.Moreover, the molecular basis of metastatic spread is also approached, making special emphasis on the site-specific pre-metastatic niche formation as another reflection of the primary tumor molecular signature.Finally, several therapeutic approaches targeting primary TME and pre-metastatic niche are suggested. For instance, a systematic analysis of the TME just adjacent to the tumor mass to establish the proportion of myofibroblasts-like cancer-associated fibroblasts (CAFs) which may in turn correspond to stemness and metastases-promotion. Or the implementation of "re-education" therapies consisting of switching tumor-supportive stromal cells into tumor-suppressive ones. In summary, to improve our clinical management of cancer, it is crucial to understand and learn how to manage the close interaction between TME and metastasis.


Assuntos
Neoplasias/genética , Microambiente Tumoral/genética , Humanos
12.
Expert Opin Biol Ther ; 21(12): 1609-1621, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33896307

RESUMO

Introduction: Trypsinogen and chymotrypsinogen have been used clinically in tissue repair due to their ability to resolve inflammatory symptoms. Recently, novel evidence has supported the anti-tumourigenic potential of a mixture of trypsinogen and chymotrypsinogen.Areas covered: First, we analyze the structure of these proteases and the effects of pancreatic proteinases on tissue repair, inflammation and the immune system. Second, we summarize studies that provided evidence of the effects of pancreatic (pro)enzymes on tumor cells both in vitro and in vivo and some successful clinical applications of pancreatic (pro)enzymes. Finally, we study pancreatic (pro)enzymes potential molecular targets, such as the proteinase-activated receptors (PARs).Expert opinion: This novel therapy has been shown to have effective antitumor effects. Treatment with these (pro) enzymes sensitizes Cancer Stem Cells (CSCs) which may allow chemotherapy and radiotherapy to be more effective, which could positively affect the recovery of cancer patients.


Assuntos
Neoplasias , Tripsinogênio , Quimotripsina , Quimotripsinogênio , Humanos , Neoplasias/tratamento farmacológico , Tripsina
13.
Bioeng Transl Med ; 6(1): e10192, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33532591

RESUMO

Tissue engineering (TE) seeks to fabricate implants that mimic the mechanical strength, structure, and composition of native tissues. Cartilage TE requires the development of functional personalized implants with cartilage-like mechanical properties capable of sustaining high load-bearing environments to integrate into the surrounding tissue of the cartilage defect. In this study, we evaluated the novel 1,4-butanediol thermoplastic polyurethane elastomer (b-TPUe) derivative filament as a 3D bioprinting material with application in cartilage TE. The mechanical behavior of b-TPUe in terms of friction and elasticity were examined and compared with human articular cartilage, PCL, and PLA. Moreover, infrapatellar fat pad-derived human mesenchymal stem cells (MSCs) were bioprinted together with scaffolds. in vitro cytotoxicity, proliferative potential, cell viability, and chondrogenic differentiation were analyzed by Alamar blue assay, SEM, confocal microscopy, and RT-qPCR. Moreover, in vivo biocompatibility and host integration were analyzed. b-TPUe demonstrated a much closer compression and shear behavior to native cartilage than PCL and PLA, as well as closer tribological properties to cartilage. Moreover, b-TPUe bioprinted scaffolds were able to maintain proper proliferative potential, cell viability, and supported MSCs chondrogenesis. Finally, in vivo studies revealed no toxic effects 21 days after scaffolds implantation, extracellular matrix deposition and integration within the surrounding tissue. This is the first study that validates the biocompatibility of b-TPUe for 3D bioprinting. Our findings indicate that this biomaterial can be exploited for the automated biofabrication of artificial tissues with tailorable mechanical properties including the great potential for cartilage TE applications.

14.
Nanomedicine (Lond) ; 15(23): 2311-2324, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32969312

RESUMO

The use of nanotechnology has become a promising approach in the treatment of cancer. However, most intravenously injected nanoparticles (NPs) do not effectively reach the tumor mass due to the biological barriers in the body. In an attempt to unify clinical criteria and basic research, we have collected the latest studies and described novel alternatives such as the use of NPs covered with cell membranes to increase NP delivery efficiency. Furthermore, we focus on the prospect of using the cell's natural messengers, exosomes, as vehicles to transport anti-cancer agents and we discuss the technical complications involved. Finally, we propose novel approaches to produce engineered exosomes which may overcome such technical limitations in order to achieve a proper anti-cancer nanotherapy.


Assuntos
Antineoplásicos , Exossomos , Nanopartículas , Neoplasias , Antineoplásicos/uso terapêutico , Sistemas de Liberação de Medicamentos , Humanos , Nanotecnologia , Neoplasias/tratamento farmacológico
15.
Cancers (Basel) ; 12(2)2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32045987

RESUMO

Colorectal cancer treatment has advanced over the past decade. The drug 5-fluorouracil is still used with a wide percentage of patients who do not respond. Therefore, a challenge is the identification of predictive biomarkers. The protein kinase R (PKR also called EIF2AK2) and its regulator, the non-coding pre-mir-nc886, have multiple effects on cells in response to numerous types of stress, including chemotherapy. In this work, we performed an ambispective study with 197 metastatic colon cancer patients with unresectable metastases to determine the relative expression levels of both nc886 and PKR by qPCR, as well as the location of PKR by immunohistochemistry in tumour samples and healthy tissues (plasma and colon epithelium). As primary end point, the expression levels were related to the objective response to first-line chemotherapy following the response evaluation criteria in solid tumours (RECIST) and, as the second end point, with survival at 18 and 36 months. Hierarchical agglomerative clustering was performed to accommodate the heterogeneity and complexity of oncological patients' data. High expression levels of nc886 were related to the response to treatment and allowed to identify clusters of patients. Although the PKR mRNA expression was not associated with chemotherapy response, the absence of PKR location in the nucleolus was correlated with first-line chemotherapy response. Moreover, a relationship between survival and the expression of both PKR and nc886 in healthy tissues was found. Therefore, this work evaluated the best way to analyse the potential biomarkers PKR and nc886 in order to establish clusters of patients depending on the cancer outcomes using algorithms for complex and heterogeneous data.

16.
Sci Rep ; 9(1): 11359, 2019 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-31388092

RESUMO

Cancer stem cells (CSCs) subpopulation within the tumour is responsible for metastasis and cancer relapse. Here we investigate in vitro and in vivo the effects of a pancreatic (pro)enzyme mixture composed of Chymotrypsinogen and Trypsinogen (PRP) on CSCs derived from a human pancreatic cell line, BxPC3. Exposure of pancreatic CSCs spheres to PRP resulted in a significant decrease of ALDEFLUOR and specific pancreatic CSC markers (CD 326, CD 44 and CxCR4) signal tested by flow cytometry, further CSCs markers expression was also analyzed by western and immunofluorescence assays. PRP also inhibits primary and secondary sphere formation. Three RT2 Profiler PCR Arrays were used to study gene expression regulation after PRP treatment and resulted in, (i) epithelial-mesenchymal transition (EMT) inhibition; (ii) CSCs related genes suppression; (iii) enhanced expression of tumour suppressor genes; (iv) downregulation of migration and metastasis genes and (v) regulation of MAP Kinase Signalling Pathway. Finally, in vivo anti-tumor xenograft studies demonstrated high anti-tumour efficacy of PRP against tumours induced by BxPC3 human pancreatic CSCs. PRP impaired engrafting of pancreatic CSC's tumours in nude mice and displayed an antigrowth effect toward initiated xenografts. We concluded that (pro)enzymes treatment is a valuable strategy to suppress the CSC population in solid pancreatic tumours.


Assuntos
Quimotripsinogênio/farmacologia , Transição Epitelial-Mesenquimal , Genes Supressores de Tumor , Sistema de Sinalização das MAP Quinases , Células-Tronco Neoplásicas/efeitos dos fármacos , Neoplasias Pancreáticas/tratamento farmacológico , Tripsinogênio/farmacologia , Animais , Linhagem Celular Tumoral , Quimotripsinogênio/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos Nus , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/fisiologia , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/fisiopatologia , Tripsinogênio/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Acta Biomater ; 90: 146-156, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30910621

RESUMO

Cartilage degeneration or damage treatment is still a challenge, but, tissue engineering strategies, which combine cell therapy strategies, which combine cell therapy and scaffolds, and have emerged as a promising new approach. In this regard, polyurethanes and polyacrylates polymers have been shown to have clinical potential to treat osteochondral injuries. Here, we have used polymer microarrays technology to screen 380 different polyurethanes and polyacrylates polymers. The top polymers with potential to maintain chondrocyte viability were selected, with scale-up studies performed to evaluate their ability to support chondrocyte proliferation during long-term culture, while maintaining their characteristic phenotype. Among the selected polymers, poly (methylmethacrylate-co-methacrylic acid), showed the highest level of chondrogenic potential and was used to create a 3D hydrogel. Ultrastructural morphology, microstructure and mechanical testing of this novel hydrogel revealed robust characteristics to support chondrocyte growth. Furthermore, in vitro and in vivo biological assays demonstrated that chondrocytes cultured on the hydrogel had the capacity to produce extracellular matrix similar to hyaline cartilage, as shown by increased expression of collagen type II, aggrecan and Sox9, and the reduced expression of the fibrotic marker's collagen type I. In conclusion, hydrogels generated from poly (methylmethacrylate-co-methacrylic acid) created the appropriate niche for chondrocyte growth and phenotype maintenance and might be an optimal candidate for cartilage tissue-engineering applications. SIGNIFICANCE STATEMENT: Articular cartilage has limited self-repair ability due to its avascular nature, therefore tissue engineering strategies have emerged as a promising new approach. Synthetic polymers displaygreat potential and are widely used in the clinical setting. In our study, using the polymer microarray technique a novel type of synthetic polyacrylate was identified, that was converted into hydrogels for articular cartilage regeneration studies. The hydrogel based on poly (methylmethacrylate-co-methacrylic acid-co-PEG-diacrylate) had a controlable ultrastructural morphology, microstructure (porosity) and mechanical properties (stiffness) appropriate for cartilage engineering. Our hydrogel created the optimal niche for chondrocyte growth and phenotype maintenance for long-term culture, producing a hyaline-like cartilage extracellular matrix. We propose that this novel polyacrylate hydrogel could be an appropriate support to help in the treatment efficient cartilage regeneration.


Assuntos
Resinas Acrílicas/química , Cartilagem Articular/metabolismo , Condrócitos/metabolismo , Matriz Extracelular/química , Hidrogéis/química , Engenharia Tecidual , Tecidos Suporte/química , Animais , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID
18.
Crit Rev Oncol Hematol ; 131: 35-45, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30293704

RESUMO

The lack of an effective treatment against cancer is not only due to its huge heterogeneity, but also to the fact that we don't have an answer to the question on how cancer originates. Among the proposed models to explain the development of cancer, the hierarchical model has been widely accepted. Nevertheless, this model fails to explain several experimental observations such as the cancer stem cells (CSCs) location inside a tumour or the differences between primary and metastatic tumours. Moreover, increasing evidence shows that the CSC phenotype is not a rigid state. Here, we present a critical review on the assumed tumour development models emphasizing the relevance of the dynamic and changing nature of cancer and the CSCs population in which the tumour microenvironment plays a crucial role and we propose a new model of tumour origin that could have an impact on new therapeutic strategies.


Assuntos
Transição Epitelial-Mesenquimal , Neoplasias/patologia , Células-Tronco Neoplásicas/patologia , Microambiente Tumoral , Animais , Humanos
19.
Cancer Lett ; 429: 78-88, 2018 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-29733965

RESUMO

Cancer stem cells (CSCs) are responsible for tumor initiation, metastasis and cancer recurrence, however the involvement of microenvironment is crucial. Here, we have analyzed how human mesenchymal stem cells (MSCs)-derived conditioned medium (CM) affect colon and melanoma CSCs enrichment and maintenance. Our results strongly suggest that the secretome of CM-MSCs selects and maintains subpopulations with high expression of CSCs markers and ALDH1 activity, low proliferation rates with G1 phase arrest, and notably retain in vivo these properties. Cytogenetic analyses indicated that CM-cultured cells contain alterations in chromosome 17 (17q25). Subsequent SKY-FISH analyses suggested that genes located in 17q25 might be involved in stem-cell maintenance. The characterization of secreted proteins present in CM-MSCs revealed that four cytokines and seven growth factors are directly linked to the CSCs enrichment reported in this study. Further analyses revealed that the combination of just IL6 and HGF is enough to provide cancer cells with better stemness properties. In conclusion, this study demonstrates how specific chromosomal alterations present in CSCs subpopulations might represent an advantage for their in vitro maintenance and in vivo stemness properties.


Assuntos
Meios de Cultivo Condicionados/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Neoplásicas/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos , Família Aldeído Desidrogenase 1 , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Cromossomos Humanos Par 17/genética , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Meios de Cultivo Condicionados/metabolismo , Citocinas/genética , Citocinas/metabolismo , Células HCT116 , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Isoenzimas/genética , Isoenzimas/metabolismo , Melanoma/metabolismo , Melanoma/patologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Neoplásicas/citologia , Células-Tronco Neoplásicas/metabolismo , Retinal Desidrogenase/genética , Retinal Desidrogenase/metabolismo , Microambiente Tumoral/genética
20.
Sci Rep ; 7(1): 13998, 2017 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-29070896

RESUMO

Proteolytic enzymes have shown efficacy in cancer therapy. We present a combination of the two pro-enzymes Trypsinogen and Chymotrypsinogen A with potent in vitro and in vivo anti-tumour efficacy. A synergetic anti-tumour effect for Trypsinogen and Chymotrypsinogen A was determined at a ratio 1:6 (named PRP) using 24 human cancer cell lines. The antiangiogenic effect of PRP was analysed by matrigel-based tube formation and by fibrous capsule formation assays. Furthermore, cell invasion and wound healing assays together with qRT-PCR determination of epithelial-to-mesenchymal transition (EMT) markers were performed on human cancer cells treated with PRP. Additionally, in vivo pharmacokinetic studies were implemented and the PRP's anti-tumour efficacy was explored against orthotopic pancreatic and ovarian cancer tumours. PRP formulation was proven to inhibit in vitro angiogenesis, tumour growth, cancer cell migration and invasiveness; and to be an effective and well tolerated in vivo anti-tumour treatment. Finally, the clinical efficacy of a suppository formulation containing both pancreatic pro-enzymes in the context of a UK Pharmaceuticals Special Scheme was evaluated in advanced cancer patients. Consequently, PRP could have relevant oncological clinical applications for the treatment of advanced or metastatic pancreatic adenocarcinoma and advanced epithelial ovarian cancer.


Assuntos
Quimotripsinogênio/administração & dosagem , Precursores Enzimáticos/administração & dosagem , Neoplasias Ovarianas/prevenção & controle , Pâncreas/enzimologia , Neoplasias Pancreáticas/prevenção & controle , Tripsinogênio/administração & dosagem , Animais , Apoptose , Proliferação de Células , Feminino , Humanos , Camundongos , Camundongos Nus , Metástase Neoplásica , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Projetos Piloto , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
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