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1.
Int J Mol Sci ; 24(3)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36769377

RESUMO

Cervical cancer is the fourth most common cancer among women worldwide. The main factor associated with the onset and progression of this neoplasia is the human papillomavirus (HPV) infection. The HPV-oncogenes E6 and E7 are critical drivers of cellular transformation, promoting the expression of oncogenes such as KCNH1. The phytochemical α-mangostin (AM) is a potent antineoplastic and antiviral compound. However, its effects on HPV oncogenes and KCNH1 gene expression remain unknown. This study evaluated the effects of AM on cell proliferation, cell cycle distribution and gene expression, including its effects on tumor growth in xenografted mice. AM inhibited cell proliferation in a concentration-dependent manner, being the most sensitive cell lines those with the highest number of HPV16 copies. In addition, AM promoted G1-cell cycle arrest in CaSki cells, while led to cell death in SiHa and HeLa cells. Of interest was the finding of an AM-dependent decreased gene expression of E6, E7 and KCNH1 both in vitro and in vivo, as well as the modulation of cytokine expression, Ki-67, and tumor growth inhibition. On these bases, we suggest that AM represents a good option as an adjuvant for the treatment and prevention of cervical cancer.


Assuntos
Proteínas Oncogênicas Virais , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Humanos , Feminino , Animais , Camundongos , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/metabolismo , Células HeLa , Proteínas E7 de Papillomavirus/genética , Proteínas E7 de Papillomavirus/metabolismo , Proteínas Repressoras/genética , Oncogenes , Proliferação de Células , Expressão Gênica , Canais de Potássio Éter-A-Go-Go/genética
2.
Nature ; 531(7594): 366-70, 2016 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-26934221

RESUMO

Observing marine mammal (MM) populations continuously in time and space over the immense ocean areas they inhabit is challenging but essential for gathering an unambiguous record of their distribution, as well as understanding their behaviour and interaction with prey species. Here we use passive ocean acoustic waveguide remote sensing (POAWRS) in an important North Atlantic feeding ground to instantaneously detect, localize and classify MM vocalizations from diverse species over an approximately 100,000 km(2) region. More than eight species of vocal MMs are found to spatially converge on fish spawning areas containing massive densely populated herring shoals at night-time and diffuse herring distributions during daytime. We find the vocal MMs divide the enormous fish prey field into species-specific foraging areas with varying degrees of spatial overlap, maintained for at least two weeks of the herring spawning period. The recorded vocalization rates are diel (24 h)-dependent for all MM species, with some significantly more vocal at night and others more vocal during the day. The four key baleen whale species of the region: fin, humpback, blue and minke have vocalization rate trends that are highly correlated to trends in fish shoaling density and to each other over the diel cycle. These results reveal the temporospatial dynamics of combined multi-species MM foraging activities in the vicinity of an extensive fish prey field that forms a massive ecological hotspot, and would be unattainable with conventional methodologies. Understanding MM behaviour and distributions is essential for management of marine ecosystems and for accessing anthropogenic impacts on these protected marine species.


Assuntos
Organismos Aquáticos/fisiologia , Comportamento Alimentar , Peixes/fisiologia , Mamíferos/fisiologia , Comportamento Predatório , Vocalização Animal , Acústica , Animais , Oceano Atlântico , Dieta/veterinária , Ecossistema , Masculino , Fatores de Tempo , Baleias/fisiologia
3.
Scand J Immunol ; 90(3): e12802, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31269269

RESUMO

Glucose and nutrient uptake is essential in supporting T cell activation and is increased upon CD3/CD28 stimulation. As T cells from pleural effusions secondary to lung cancer show impaired function, we hypothesized that these cells might have altered expression of nutrient transporters. Here, we analysed by flow cytometry the expression of the transferrin receptor CD71, amino acid transporter CD98 and glucose transporter Glut1 and glucose uptake in pleural effusion-derived T cells from lung cancer patients, after stimulation via CD3/CD28 under normoxia or hypoxia (2% O2 ). We compared the response of T cells from pleural effusions secondary to lung cancer with that of T cells from nonmalignant effusions. In memory T cells from both groups, anti-CD3/CD28-stimulation under normoxia upregulated CD98 and CD71 expression (measured as median fluorescence intensity, MFI) in comparison with anti-CD3-stimulation. Costimulation under hypoxia tended to increase CD98 expression compared to CD3-stimulation in memory T cells from both groups. Remarkably, in the cancer group, memory T cells stimulated via CD3/CD28 under hypoxia failed to increase CD71 and Glut1 expression levels compared to the cells receiving anti-CD3 stimulation, a phenomenon that contrasted with the behaviour of memory T cells from nonmalignant effusions. Consequently, glucose uptake by memory T cells from the cancer group was not increased after CD3/CD28 stimulation under hypoxia, implying that their glycolytic metabolism is defective. As this process is required for inducing an antitumoural response, our study suggests that memory T cells are rendered dysfunctional and are unable to eliminate lung tumour cells.


Assuntos
Antígenos CD28/metabolismo , Complexo CD3/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Glucose/metabolismo , Memória Imunológica/imunologia , Neoplasias Pulmonares/metabolismo , Derrame Pleural/metabolismo , Linfócitos T/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Neoplasias Pulmonares/imunologia , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-Idade , Derrame Pleural/imunologia , Linfócitos T/metabolismo
4.
Rev Invest Clin ; 71(3): 186-194, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31184333

RESUMO

BACKGROUND: Expression and activity of the potassium channel ether-à-go-go-1 (EAG1) are strongly related to carcinogenesis and tumor progression, which can be exploited for therapeutic purposes. EAG1 activity may be reduced by preventing its phosphorylation with epidermal growth factor receptor (EGFR) kinase inhibitors and by astemizole, which blocks the channel pore and downregulates its gene expression. OBJECTIVE: We aimed to study the potential cooperative antiproliferative effect of the EGFR inhibitor gefitinib and the EAG1-blocker astemizole, in breast cancer cells. MATERIALS AND METHODS: The cells were characterized by immunocytochemistry. Inhibitory concentrations were determined by non-linear regression analysis using dose-response curves. The nature of the pharmacological effect was evaluated by the combination index equation while cell cycle analysis was studied by flow cy-tometry. RESULTS: Astemizole and gefitinib inhibited cell proliferation in a concentration-dependent manner, with inhibitory concentrations (IC 50) values of 1.72 µM and 0.51 µM, respectively. All combinations resulted in a synergistic antiproliferative effect. The combination of astemizole and gefitinib diminished the percentage of cells in G2/M and S phases, while increased accumulation in G0/G1 of the cell cycle. CONCLUSIONS: Astemizole and gefitinib synergistically inhibited proliferation in breast cancer cells expressing both EGFR and EAG1. Our results suggest that the combined treatment increased cell death by targeting the oncogenic activity of EAG1.


Assuntos
Antineoplásicos/farmacologia , Astemizol/farmacologia , Neoplasias da Mama/tratamento farmacológico , Gefitinibe/farmacologia , Antineoplásicos/administração & dosagem , Astemizol/administração & dosagem , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Canais de Potássio Éter-A-Go-Go/antagonistas & inibidores , Canais de Potássio Éter-A-Go-Go/genética , Feminino , Gefitinibe/administração & dosagem , Regulação Neoplásica da Expressão Gênica , Humanos , Concentração Inibidora 50 , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/farmacologia
5.
Cancer Immunol Immunother ; 66(6): 765-776, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28289860

RESUMO

Malignant pleural effusions are frequent in patients with advanced stages of lung cancer and are commonly infiltrated by lymphocytes and tumor cells. CD8+ T cells from these effusions have reduced effector functions. The programmed death receptor 1(PD-1)/programmed death ligand 1 (PD-L1) pathway is involved in T-cell exhaustion, and it might be responsible for T-cell dysfunction in lung cancer patients. Here, we show that PD-L1 is expressed on tumor cell samples from malignant effusions, on lung cancer cell lines, and, interestingly, on MRC-5 lung fibroblasts. PD-L1 was up-regulated in lung cancer cell lines upon treatment with IFN-gamma, but not under hypoxic conditions, as detected by RT-qPCR and flow cytometry. Blockade of PD-L1 on tumor cells restored granzyme-B expression in allogenic CD8+ T cells in vitro. Remarkably, pleural effusion CD8+ T cells that responded to the tumor antigens MAGE-3A and WT-1 (identified as CD137+ cells) were lower in frequency than CMV pp65-responding CD8+ T cells and did not have an exhausted phenotype (PD-1+ TIM-3+). Nonetheless, tumor-responding CD8+ T cells had a memory phenotype and expressed higher levels of PD-1. A PD-L1 blocking antibody increased the expression of granzyme-B and perforin on polyclonal- and tumor-stimulated CD8+ T cells. Taken together, our data show that rather than being exhausted, tumor-responding CD8+ T cells are not completely differentiated into effector cells and are prone to negative regulation by PD-L1. Hence, our study provides evidence that lung cancer patients respond to immunotherapy due to blockade of the PD-L1/PD-1 pathway.


Assuntos
Adenocarcinoma/imunologia , Antígeno B7-H1/metabolismo , Carcinoma de Células Escamosas/imunologia , Neoplasias Pulmonares/imunologia , Mesotelioma/imunologia , Derrame Pleural/imunologia , Receptor de Morte Celular Programada 1/metabolismo , Subpopulações de Linfócitos T/imunologia , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Células Cultivadas , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/patologia , Masculino , Mesotelioma/patologia , Pessoa de Meia-Idade , Derrame Pleural/patologia , Transdução de Sinais
6.
BMC Cancer ; 15: 21, 2015 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-25622528

RESUMO

BACKGROUND: Over the past few years, the concurrent use of cisplatin-based chemotherapy and radiation therapy has dramatically improved the local response and increased overall survival in early-stage cervical cancer. However, for the advanced stages of the disease this standard treatment has proved insufficient. We investigated the capacity of Mifepristone and ICI 182,780, which are anti-progestin and anti-estrogen drugs, respectively, to act as chemo-radiosensitizing agents in cervical cancer cells and cervix xenografts. METHODS: The effect of chemo-radiation alone or combined with Mifepristone or ICI 182,780 was evaluated in HeLa cells and with tumor growth in cervix xenografts. After concomitant chemo-radiotherapy, the effect of each of these antihormonal agents on apoptosis (determined by Annexing V assay) and the cell cycle phases were determined by flow cytometry. The expression of angiogenic factor VEGF in tumor samples was determined using quantitative RT-PCR analysis of VEGF gene expression. RESULTS: Compared to radiation alone or radiation/cisplatin therapy, there was significantly higher cytotoxicity and a greater antitumoral effect with the combined application of radiation/cisplatin and Mifepristone or ICI 182,780. Analyses of the apoptosis and cell cycle demonstrated changes only with ICI, not with Mifepristone, when was applied in combination with radiation/cisplatin. The analysis of VEGF mRNA expression levels in tumors at the end of the study demonstrated a significant inhibition, compared to radiation only or the radiation/cisplatin treatment, after concurrent chemo-radiotherapy and each one of the antihormonal drugs. CONCLUSION: Mifepristone and ICI 182,780 may be potentially promising chemo-radiosensitizing compounds to be used in combination with ionizing irradiation and cisplatin in the treatment of patients with advanced cervical cancer.


Assuntos
Antineoplásicos Hormonais/farmacologia , Radiação Ionizante , Neoplasias do Colo do Útero/patologia , Animais , Antineoplásicos/farmacologia , Antineoplásicos Hormonais/administração & dosagem , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/efeitos da radiação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Cisplatino/administração & dosagem , Cisplatino/farmacologia , Modelos Animais de Doenças , Feminino , Expressão Gênica , Células HeLa , Humanos , Camundongos , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/efeitos da radiação , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/radioterapia , Fatores de Crescimento do Endotélio Vascular/genética , Fatores de Crescimento do Endotélio Vascular/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Exp Lung Res ; 40(1): 12-21, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24246049

RESUMO

The ribonucleoproteins (hnRNPs) have important roles in multiple aspects of nucleic acid metabolism and in the regulation of different cellular processes. Abnormal expression of hnRNPs has been reported in several types of cancer including lung, pancreatic, and gastric carcinomas. Heterogenous tumor cell populations generate a tumor microenvironment that can present normoxic, hypoxic, or acidic regions. The analysis of hnRNP transcriptional responses considering the changing nature of the tumor microenvironment is important to understand tumor cell survival under stress conditions. We analyzed the transcriptional response of hnRNPA0, A1, A2, B1, and A3 in lung tumor cell lines under acidosis, hypoxia, and serum deprivation conditions. We used qRT-PCR to obtain a relative quantification of the hnRNPA/B transcript levels. We found that the hnRNPA2 transcript was the most abundant, followed by B1, A0, and A1. Expression of hnRNPA3 was the lowest, although its transcript levels were the most constant. hnRNPA/B transcript levels in lung tumor cell lines responded to changes in the microenvironment; however, hnRNPB1 transcript levels relative to hnRNPA2 expression did no change in all tested stress conditions, indicating that the alternative splicing between these isoforms was constant. hnRNPA1, A2, and B1 transcript levels were upregulated under serum deprivation conditions; possibly to promote a migration phenotype. Our data provide new insights into the transcriptional responses of ribonucleoproteins that might favor tumor cell survival and migration.


Assuntos
Acidose/genética , Hipóxia/genética , Neoplasias Pulmonares/genética , Ribonucleoproteínas/genética , Transcrição Gênica/genética , Linhagem Celular Tumoral , Regulação para Baixo/genética , Humanos , Pulmão/patologia , Regulação para Cima/genética
8.
Metabolites ; 14(2)2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38392995

RESUMO

Solid tumors frequently present a heterogeneous tumor microenvironment. Because tumors have the potential to proliferate quickly, the consequence is a reduction in the nutrients, a reduction in the pH (<6.8), and a hypoxic environment. Although it is often assumed that tumor clones show a similar growth rate with little variations in nutrient consumption, the present study shows how growth-specific rate (µ), the specific rates of glucose, lactate, and glutamine consumption (qS), and the specific rates of lactate and glutamate production (qP) of 2D-cultured lung tumor cells are affected by changes in their environment. We determined in lung tumor cells (A427, A549, Calu-1, and SKMES-1) the above mentioned kinetic parameters during the exponential phase under different culture conditions, varying the predominant carbon source, pH, and oxygen tension. MCF-7 cells, a breast tumor cell line that can consume lactate, and non-transformed fibroblast cells (MRC-5) were included as controls. We also analyzed how cell-cycle progression and the amino acid transporter CD98 expression were affected. Our results show that: (1) In glucose presence, µ increased, but qS Glucose and qP Lactate decreased when tumor cells were cultured under acidosis as opposed to neutral conditions; (2) most lung cancer cell lines consumed lactate under normoxia or hypoxia; (3) although qS Glutamine diminished under hypoxia or acidosis, it slightly increased in lactate presence, a finding that was associated with CD98 upregulation; and (4) under acidosis, G0/G1 arrest was induced in A427 cancer cells, although this phenomenon was significantly increased when glucose was changed by lactate as the predominant carbon-source. Hence, our results provide an understanding of metabolic responses that tumor cells develop to survive under stressful conditions, providing clues for developing promising opportunities to improve traditional cancer therapies.

9.
J Funct Biomater ; 14(12)2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-38132810

RESUMO

Male survivors of childhood cancer have been known to be afflicted with azoospermia. To combat this, the isolation and purification of spermatogonial stem cells (SSCs) are crucial. Implementing scaffolds that emulate the extracellular matrix environment is vital for promoting the regeneration and proliferation of SSCs. This research aimed to evaluate the efficiency of nanocomposite scaffolds based on alginate, chitosan, and graphene oxide (GO) in facilitating SSCs proliferation. To analyze the cytotoxicity of the scaffolds, an MTT assay was conducted at 1, 3, and 7 days, and the sample containing 30 µg/mL of GO (ALGCS/GO30) exhibited the most favorable results, indicating its optimal performance. The identity of the cells was confirmed using flow cytometry with C-Kit and GFRα1 markers. The scaffolds were subjected to various analyses to characterize their properties. FTIR was employed to assess the chemical structure, XRD to examine crystallinity, and SEM to visualize the morphology of the scaffolds. To evaluate the proliferation of SSCs, qRT-PCR was used. The study's results demonstrated that the ALGCS/GO30 nanocomposite scaffold exhibited biocompatibility and facilitated the attachment and proliferation of SSCs. Notably, the scaffold displayed a significant increase in proliferation markers compared to the control group, indicating its ability to support SSC growth. The expression level of the PLZF protein was assessed using the Immunocytochemistry method. The observations confirmed the qRT-PCR results, which indicated that the nanocomposite scaffolds had higher levels of PLZF protein expression than scaffolds without GO. The biocompatible ALGCS/GO30 is a promising alternative for promoting SSC proliferation in in vitro applications.

10.
Cancer Immunol Immunother ; 61(7): 1065-80, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22159518

RESUMO

Lung cancer is the second most common form of cancer and the leading cause of cancer death worldwide. Pleural effusions, containing high numbers of mononuclear and tumor cells, are frequent in patients with advanced stages of lung cancer. We reported that in pleural effusions from primary lung cancer, the CD8+ T cell subpopulation, and particularly the terminally differentiated subset, is reduced compared to that of non-malignant effusions. We analyzed the participation of activation-induced cell death (AICD) and extrinsic pathways (type I or II) as mechanisms for the decrease in pleural effusion CD8+ T cell subpopulation. Pleural effusion or peripheral blood CD4+ and CD8+ T cells, from lung cancer patients, were stimulated with anti-CD3 antibody and analyzed for (a) apoptosis by annexin-V-binding and TUNEL assay, (b) transcript levels of Fas ligand (FasL) and TRAIL by real-time RT-PCR, (c) expression of FasL and TRAIL, measured as integrated mean fluorescence intensities (iMFI) by flow cytometry, (d) expression of Bcl-2 and BIM molecules, measured as MFI, and (e) apoptosis inhibition using caspase-8 and -9 inhibitors. Pleural effusion CD8+ T cells, but not CD4+ T cells, from cancer patients underwent AICD. Blocking FasL/Fas pathway protected from AICD. Upregulation of FasL and TRAIL expressions was found in pleural effusion CD8+ T cells, which also showed a subset of Bcl-2 low cells. In memory CD8+ T cells, AICD depended on both extrinsic and intrinsic apoptotic pathways. Hence, in the pleural space of lung cancer patients, AICD might compromise the antitumor function of CD8+ T cells.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Proteína Ligante Fas/imunologia , Neoplasias Pulmonares/imunologia , Derrame Pleural/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose/imunologia , Morte Celular/imunologia , Feminino , Humanos , Memória Imunológica , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Derrame Pleural/patologia , Subpopulações de Linfócitos T/imunologia
11.
Clin Dev Immunol ; 2012: 741741, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23118782

RESUMO

Lung cancer is the leading cause of cancer deaths worldwide and one of the most common types of cancers. The limited success of chemotherapy and radiotherapy regimes have highlighted the need to develop new therapies like antitumor immunotherapy. CD8+ T-cells represent a major arm of the cell-mediated anti-tumor response and a promising target for developing T-cell-based immunotherapies against lung cancer. Lung tumors, however, have been considered to possess poor immunogenicity; even so, lung tumor-specific CD8+ T-cell clones can be established that possess cytotoxicity against autologous tumor cells. This paper will focus on the alterations induced in CD8+ T-cells by lung cancer. Although memory CD8+ T-cells infiltrate lung tumors, in both tumor-infiltrating lymphocytes (TILs) and malignant pleural effusions, these cells are dysfunctional and the effector subset is reduced. We propose that chronic presence of lung tumors induces dysfunctions in CD8+ T-cells and sensitizes them to activation-induced cell death, which may be associated with the poor clinical responses observed in immunotherapeutic trials. Getting a deeper knowledge of the evasion mechanisms lung cancer induce in CD8+ T-cells should lead to further understanding of lung cancer biology, overcome tumor evasion mechanisms, and design improved immunotherapeutic treatments for lung cancer.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Neoplasias Pulmonares/imunologia , Animais , Humanos , Imunoterapia/métodos , Neoplasias Pulmonares/terapia , Linfócitos do Interstício Tumoral/imunologia , Derrame Pleural Maligno/imunologia
12.
Rev Invest Clin ; 64(3): 284-93, 2012.
Artigo em Espanhol | MEDLINE | ID: mdl-23045951

RESUMO

Cells of the innate immune system are involved in discriminating between the innocuous cell death (apoptosis) which occurs in tissues during homeostasis, and the cell death associated to tissue damage (necrosis). Recently, a new variant of apoptosis termed immunogenic apoptosis has been described. In cancer, this type of cell death has acquired great relevance. In vitro and in vivo experimental models support that radiotherapy and some chemotherapeutic drugs induce the immunogenic apoptosis of malignant cells. Dying cells express at cytoplasmic membrane or release several nuclear or intracytoplasmic molecules termed "danger signals" or damage associated molecular patterns (DAMPs). DAMPs alert the organism and play a role inducing an efficient anti-tumor immune response. In this review, the importance of cell death by immunogenic apoptosis, the cytotoxic drugs that induce this type of cell death, the biologic role of some DAMPs and their participation in the activation of the antitumor immune response, in particular in the phagocytic cell, are indicated. The goal of this information should impact in improving the participation of the immune system in the recognition and efficient elimination of the residual tumor cells and to overcome the evasion mechanisms of tumor cells. This knowledge should lead to a better control of the growth of tumors with a concomitant reduction in the tumor recurrence. Also, an increase in the survival of the cancer patients or probably their definitive cure could be reached in the future.


Assuntos
Apoptose/imunologia , Neoplasias/imunologia , Neoplasias/terapia , Proteína HMGB1/fisiologia , Humanos
13.
Front Genet ; 13: 823238, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35186039

RESUMO

Circular RNAs (CircRNAs) are a class of small endogenous noncoding RNA that are formed by means of either the spliceosome or lariat-type splicing. CircRNAs have multiple regulatory functions and have been detected in different cell types, like normal, tumor and immune cells. CircRNAs have been suggested to regulate T cell functions in response to cancer. CircRNAs can enter into T cells and promote the expression of molecules that either trigger antitumoral responses or promote suppression and the consequent evasion to the immune response. Additionally, circRNAs may promote tumor progression and resistance to anticancer treatment in different types of neoplasias. In this minireview we discuss the impact of circRNAs and its function in the regulation of the T-cells in immune response caused by cancer therapies.

14.
Artigo em Inglês | MEDLINE | ID: mdl-36231664

RESUMO

The G-protein-coupled receptor for estrogen (GPER1) is a transmembrane receptor involved in the progression and development of various neoplasms whose ligand is estradiol (E2). 17ß-aminoestrogens (17ß-AEs) compounds, analogs to E2, are possible candidates for use in hormone replacement therapy (HRT), but our knowledge of their pharmacological profile is limited. Thus, we explored the molecular recognition of GPER1 with different synthetic 17ß-AEs: prolame, butolame, and pentolame. We compared the structure and ligand recognition sites previously reported for a specific agonist (G1), antagonists (G15 and G36), and the natural ligand (E2). Then, the biological effects of 17ß-AEs were analyzed through cell viability and cell-cycle assays in two types of female cancer. In addition, the effect of 17ß-AEs on the phosphorylation of the oncoprotein c-fos was evaluated, because this molecule is modulated by GPER1. Molecular docking analysis showed that 17ß-AEs interacted with GPER1, suggesting that prolame joins GPER1 in a hydrophobic cavity, similarly to G1, G15, and E2. Prolame induced cell proliferation in breast (MCF-7) and cervical cancer (SIHA) cells; meanwhile, butolame and pentolame did not affect cell proliferation. Neither 17ß-AEs nor E2 changed the activation of c-fos in MCF-7 cells. Meanwhile, in SIHA cells, E2 and 17ß-AEs reduced c-fos phosphorylation. Thus, our data suggest that butolame and pentolame, but not prolame, could be used for HRT without presenting a potential risk of inducing breast- or cervical-cancer-cell proliferation. The novelty of this work lies in its study of compound analogs to E2 that may represent important therapeutic strategies for women in menopause, with non-significant effects on the cell viability of cancer cells. The research focused on the interactions of GPER1, a molecule recently associated with promoting and maintaining various neoplasms.


Assuntos
Neoplasias da Mama , Receptores de Estrogênio/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Amino Álcoois , Neoplasias da Mama/tratamento farmacológico , Proliferação de Células , Estradiol/farmacologia , Estrenos , Estrogênios/farmacologia , Feminino , Humanos , Ligantes , Simulação de Acoplamento Molecular , Proteínas Oncogênicas/farmacologia
15.
Front Vet Sci ; 9: 972185, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36061122

RESUMO

The canine transmissible venereal tumor (CTVT) is the most common malignity in dogs. Because there are reports that this tumor is resistant to vincristine sulfate, the chemotherapeutic options are scarce, and the development of new therapeutic approaches is necessary. In this study, we evaluated the cytotoxic activity of vincristine, doxorubicin, temozolomide, panobinostat, toceranib, gemcitabine, cisplatin, fluorouracil, cyclophosphamide, and methotrexate on a CTVT cell line, determining that all drugs decreased the viability in a dose-dependent manner. Furthermore, they inhibit cellular migration in a time- and drug-dependent manner, as evaluated by the wound healing assay. On the other hand, vincristine, panobinostat, gemcitabine, toceranib, cyclophosphamide, and methotrexate increased the percentage of cells in the subG1 phase, and doxorubicin, temozolomide, gemcitabine, toceranib, and methotrexate decreased the percentage of cells in the synthesis phase. To efficientize the use of vincristine, only toceranib increased the cytotoxic effect of vincristine in a synergistic manner. Our results confirm the use of vincristine as the gold standard for CTVT treatment as monotherapy and suggest the use of a combinatorial and sequential treatment with toceranib.

16.
Front Genet ; 13: 960263, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36263432

RESUMO

The acetylation status of histones located in both oncogenes and tumor suppressor genes modulate cancer hallmarks. In lung cancer, changes in the acetylation status are associated with increased cell proliferation, tumor growth, migration, invasion, and metastasis. Histone deacetylases (HDACs) are a group of enzymes that take part in the elimination of acetyl groups from histones. Thus, HDACs regulate the acetylation status of histones. Although several therapies are available to treat lung cancer, many of these fail because of the development of tumor resistance. One mechanism of tumor resistance is the aberrant expression of HDACs. Specific anti-cancer therapies modulate HDACs expression, resulting in chromatin remodeling and epigenetic modification of the expression of a variety of genes. Thus, HDACs are promising therapeutic targets to improve the response to anti-cancer treatments. Besides, natural compounds such as phytochemicals have potent antioxidant and chemopreventive activities. Some of these compounds modulate the deregulated activity of HDACs (e.g. curcumin, apigenin, EGCG, resveratrol, and quercetin). These phytochemicals have been shown to inhibit some of the cancer hallmarks through HDAC modulation. The present review discusses the epigenetic mechanisms by which HDACs contribute to carcinogenesis and resistance of lung cancer cells to anticancer therapies.

17.
Hepatology ; 51(4): 1137-43, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20049907

RESUMO

Randomized controlled trials of hepatitis C virus (HCV) therapy with pegylated interferon and ribavirin have demonstrated sustained viral response rates (SVRs) of 54%-63% (efficacy). Treatment results in clinical practice (effectiveness) may not be equivalent. The goal of this study was to assess the effectiveness of HCV treatment with pegylated interferon and ribavirin in a treatment-naïve, human immunodeficiency virus (HIV)-negative, United States urban population with many ethnic minority patients. We evaluated 2,370 outpatients for HCV therapy from 2001 to 2006 in the Faculty Practice of the Albert Einstein College of Medicine or the attending-supervised Montefiore Medical Center Liver Clinic. Care was supervised by one experienced physician under conditions of everyday clinical practice, and appropriate ancillary resources were made available to all patients. Two hundred fifty-five patients were treated with a mean age of 50 years (60% male, 40% female; 58% Hispanic, 20% African American, 9% Caucasian, 13% other; 68% genotype 1, the remainder genotypes 2 or 3). Patients had at least one liver biopsy. Intention-to-treat analysis (ITT) showed SVR in 14% of genotype 1 patients and 37% in genotype 2/3 patients (P < 0.001). SVR was significantly higher in faculty practice (27%) than in clinic patients (15%) by intention-to-treat (P = 0.01) but not per-protocol analysis (46% faculty practice, 34% clinic). 3.3% of 1,656 treatment-naïve, HIV antibody-negative individuals ultimately achieved SVR. Current hepatitis C therapies may sometimes be unavailable to, inappropriate for, and ineffective in United States urban patients. Treatment with pegylated interferon and ribavirin was less effective in this population than is implied by multinational phase III controlled trials. New strategies are needed to care for such patients.


Assuntos
Antivirais/administração & dosagem , Hepatite C/tratamento farmacológico , Interferon-alfa/administração & dosagem , Polietilenoglicóis/administração & dosagem , Ribavirina/administração & dosagem , Adulto , Quimioterapia Combinada , Feminino , Hepatite C/virologia , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes , Saúde da População Urbana
18.
J Immunol Res ; 2021: 6668573, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33506060

RESUMO

Breast cancer is the most common neoplasm diagnosed in women around the world. Checkpoint inhibitors, targeting the programmed death receptor-1 or ligand-1 (PD-1/PD-L1) axis, have dramatically changed the outcome of cancer treatment. These therapies have been recently considered as alternatives for treatment of breast cancers, in particular those with the triple-negative phenotype (TNBC). A further understanding of the regulatory mechanisms of PD-L1 expression is required to increase the benefit of PD-L1/PD-1 checkpoint immunotherapy in breast cancer patients. In this review, we will compile the most recent studies evaluating PD-1/PD-L1 checkpoint inhibitors in breast cancer. We review factors that determine the therapeutic success of PD-1/PD-L1 immunotherapies in this pathology. In particular, we focus on pathways that interconnect the epithelial-mesenchymal transition (EMT) with regulation of PD-L1 expression. We also discuss the relationship between cellular metabolic pathways and PD-L1 expression that are involved in the promotion of resistance in TNBC.


Assuntos
Antígeno B7-H1/antagonistas & inibidores , Resistencia a Medicamentos Antineoplásicos/imunologia , Transição Epitelial-Mesenquimal/imunologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias de Mama Triplo Negativas/terapia , Antígeno B7-H1/metabolismo , Mama/imunologia , Mama/patologia , Mama/cirurgia , Quimioterapia Adjuvante/métodos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Mastectomia , Terapia Neoadjuvante/métodos , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/metabolismo , Intervalo Livre de Progressão , Neoplasias de Mama Triplo Negativas/imunologia , Neoplasias de Mama Triplo Negativas/mortalidade , Neoplasias de Mama Triplo Negativas/patologia , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia
19.
J Heart Lung Transplant ; 40(5): 377-386, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33648871

RESUMO

BACKGROUND: Air trapping (AT) is one of the hallmarks of allograft dysfunction after lung transplantation (LT). Inert gas‒based ventilation‒perfusion (VQ) lung scintigraphy has excellent sensitivity in the detection of AT. METHODS: We reviewed the charts of patients who underwent single or double LT between January 2012 and December 2014 (N = 193). Patients without a VQ scintigraphy at the first annual visit (n = 16) and those who did not survive till 1 year (n = 26) were excluded (final n = 151, mean age = 55.8 [SD =14] years, male = 85, female = 66). VQ scintigraphy was independently reviewed and reconciled for the presence and severity of AT by 2 investigators blinded to the clinical data (D.F.P. and D.M.). A 3-year post-transplant survival was the primary end-point. RESULTS: AT was common (n = 73, 48.3%). Patients with obstructive lung diseases as the underlying diagnosis (adjusted odds ratio [OR], 4.36, 95% CI: 1.64‒11.6; p = 0.003) and those with lower body mass index (BMI) (BMI < 25 kg/m2 and 25‒30 kg/m2; p < 0.001) had an increased risk of developing AT in the allograft. The presence of AT (adjusted OR, 2.33, 95% CI: 1.01‒5.36; p = 0.04) and peak forced expiratory volume in 1 sec (FEV1) <60% predicted during the first year after LT were independently associated with 3-year mortality. The association of AT with post-transplant mortality was the strongest among patients with BMI <30 kg/m2 and peak FEV1 <60% predicted. CONCLUSIONS: The finding of AT on VQ scintigraphy at the first annual visit after LT is independently associated with worse post-transplant mortality. The sub-group of patients who fail to achieve a peak FEV1 of 60% predicted during the first year after LT appears to be the key driver of this association.


Assuntos
Transplante de Pulmão , Pulmão/fisiopatologia , Perfusão/métodos , Cintilografia/métodos , Aloenxertos , Feminino , Seguimentos , Volume Expiratório Forçado , Sobrevivência de Enxerto , Humanos , Pulmão/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Prognóstico , Estudos Retrospectivos , Capacidade Vital
20.
Am J Cancer Res ; 11(12): 5951-5964, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35018235

RESUMO

Patients with estrogen receptor (ER) α-negative breast tumors have a poor prognosis and are not suitable for hormone therapy. Previously, we demonstrated that calcitriol, the active metabolite of vitamin D, induces ERα expression and re-establishes the response to antiestrogens in ER-negative breast cancer cells. However, the mechanisms involved in this process have not been elucidated. Therefore, the present study was undertaken to investigate the mechanisms implicated in the calcitriol-induced ERα expression in ER-negative breast cancer cells. Using EMSA and ChIP assays, we found that the calcitriol/vitamin D receptor (VDR)/retinoic X receptor (RXR) complex binds to putative vitamin D response elements (VDREs) in the ERα gene promoter region. In addition, we established by a fluorometric assay that calcitriol decreased DNA-methyltransferase and histone deacetylase activities. Flow cytometry and qPCR analyses showed that co-treatment of calcitriol with inhibitors of the histone deacetylase and DNA methyltransferase, and genistein significantly increased ERα expression, compared to that observed with the compounds alone. In conclusion, the calcitriol-dependent ERα induction in ER-negative breast cancer cells results from binding of the VDR-RXR complex to VDREs in the ERα gene promoter region, including the downregulation of enzymes with chromatin-remodeling activities. These results may bring forth novel mechanistic knowledge into the actions of calcitriol in ERα-negative breast cancer.

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