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1.
Int J Mol Sci ; 25(7)2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38612895

RESUMO

Expression of miR-21 has been found to be altered in almost all types of cancers, and it has been classified as an oncogenic microRNA. In addition, the expression of tumor suppressor gene RECK is associated with miR-21 overexpression in high-grade cervical lesions. In the present study, we analyze the role of miR-21 in RECK gene regulation in cervical cancer cells. To identify the downstream cellular target genes of upstream miR-21, we silenced endogenous miR-21 expression using siRNAs. We analyzed the expression of miR-21 and RECK, as well as functional effects on cell proliferation and migration. We found that in cervical cancer cells, there was an inverse correlation between miR-21 expression and RECK mRNA and protein expression. SiRNAs to miR-21 increased luciferase reporter activity in construct plasmids containing the RECK-3'-UTR microRNA response elements MRE21-1, MRE21-2, and MRE21-3. The role of miR-21 in cell proliferation was also analyzed, and cancer cells transfected with siRNAs exhibited a markedly reduced cell proliferation and migration. Our findings indicate that miR-21 post-transcriptionally down-regulates the expression of RECK to promote cell proliferation and cell migration inhibition in cervical cancer cell survival. Therefore, miR-21 and RECK may be potential therapeutic targets in gene therapy for cervical cancer.


Assuntos
MicroRNAs , Neoplasias do Colo do Útero , Feminino , Humanos , Neoplasias do Colo do Útero/genética , Transdução de Sinais , Proliferação de Células/genética , Movimento Celular/genética , RNA Interferente Pequeno , MicroRNAs/genética , Agitação Psicomotora , RNA de Cadeia Dupla , Proteínas Ligadas por GPI/genética
2.
Microbiol Spectr ; 12(2): e0259423, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38230926

RESUMO

Fungal infections are a growing global health concern due to the limited number of available antifungal therapies as well as the emergence of fungi that are resistant to first-line antimicrobials, particularly azoles and echinocandins. Development of novel, selective antifungal therapies is challenging due to similarities between fungal and mammalian cells. An attractive source of potential antifungal treatments is provided by ecological niches co-inhabited by bacteria, fungi, and multicellular organisms, where complex relationships between multiple organisms have resulted in evolution of a wide variety of selective antimicrobials. Here, we characterized several analogs of one such natural compound, collismycin A. We show that NR-6226C has antifungal activity against several pathogenic Candida species, including C. albicans and C. glabrata, whereas it only has little toxicity against mammalian cells. Mechanistically, NR-6226C selectively chelates iron, which is a limiting factor for pathogenic fungi during infection. As a result, NR-6226C treatment causes severe mitochondrial dysfunction, leading to formation of reactive oxygen species, metabolic reprogramming, and a severe reduction in ATP levels. Using an in vivo model for fungal infections, we show that NR-6226C significantly increases survival of Candida-infected Galleria mellonella larvae. Finally, our data indicate that NR-6226C synergizes strongly with fluconazole in inhibition of C. albicans. Taken together, NR-6226C is a promising antifungal compound that acts by chelating iron and disrupting mitochondrial functions.IMPORTANCEDrug-resistant fungal infections are an emerging global threat, and pan-resistance to current antifungal therapies is an increasing problem. Clearly, there is a need for new antifungal drugs. In this study, we characterized a novel antifungal agent, the collismycin analog NR-6226C. NR-6226C has a favorable toxicity profile for human cells, which is essential for further clinical development. We unraveled the mechanism of action of NR-6226C and found that it disrupts iron homeostasis and thereby depletes fungal cells of energy. Importantly, NR-6226C strongly potentiates the antifungal activity of fluconazole, thereby providing inroads for combination therapy that may reduce or prevent azole resistance. Thus, NR-6226C is a promising compound for further development into antifungal treatment.


Assuntos
Anti-Infecciosos , Micoses , Animais , Humanos , Antifúngicos/farmacologia , Fluconazol/farmacologia , Ferro , Candida , Micoses/microbiologia , Candida albicans , Anti-Infecciosos/farmacologia , Azóis/farmacologia , Candida glabrata , Quelantes de Ferro/farmacologia , Farmacorresistência Fúngica , Testes de Sensibilidade Microbiana , Mamíferos
3.
Med Mycol Case Rep ; 42: 100604, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37693216

RESUMO

In an 80-year-old man with long-term dysphagia, an upper endoscopy was performed and biopsy samples collected for microbiological and pathological tests, showing fungal structures. Kazachstania slooffiae was isolated in microbiological cultures that were later confirmed with DNA sequencing. Susceptibility tests were performed, and antifungal treatment was initiated with a clinical, pathological, and microbiological response.

4.
PLoS Genet ; 18(12): e1010549, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36516161

RESUMO

Flippases transport lipids across the membrane bilayer to generate and maintain asymmetry. The human fungal pathogen Candida albicans has 5 flippases, including Drs2, which is critical for filamentous growth and phosphatidylserine (PS) distribution. Furthermore, a drs2 deletion mutant is hypersensitive to the antifungal drug fluconazole and copper ions. We show here that such a flippase mutant also has an altered distribution of phosphatidylinositol 4-phosphate [PI(4)P] and ergosterol. Analyses of additional lipid transporters, i.e. the flippases Dnf1-3, and all the oxysterol binding protein (Osh) family lipid transfer proteins, i.e. Osh2-4 and Osh7, indicate that they are not critical for filamentous growth. However, deletion of Osh4 alone, which exchanges PI(4)P for sterol, in a drs2 mutant can bypass the requirement for this flippase in invasive filamentous growth. In addition, deletion of the lipid phosphatase Sac1, which dephosphorylates PI(4)P, in a drs2 mutant results in a synthetic growth defect, suggesting that Drs2 and Sac1 function in parallel pathways. Together, our results indicate that a balance between the activities of two putative lipid transporters regulates invasive filamentous growth, via PI(4)P. In contrast, deletion of OSH4 in drs2 does not restore growth on fluconazole, nor on papuamide A, a toxin that binds PS in the outer leaflet of the plasma membrane, suggesting that Drs2 has additional role(s) in plasma membrane organization, independent of Osh4. As we show that C. albicans Drs2 localizes to different structures, including the Spitzenkörper, we investigated if a specific localization of Drs2 is critical for different functions, using a synthetic physical interaction approach to restrict/stabilize Drs2 at the Spitzenkörper. Our results suggest that the localization of Drs2 at the plasma membrane is critical for C. albicans growth on fluconazole and papuamide A, but not for invasive filamentous growth.


Assuntos
Candida albicans , Proteínas de Saccharomyces cerevisiae , Humanos , Candida albicans/metabolismo , Adenosina Trifosfatases/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Fluconazol/farmacologia , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo
5.
Cells ; 11(8)2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35456001

RESUMO

Autophagy is a highly conserved multistep lysosomal degradation process in which cellular components are localized to autophagosomes, which subsequently fuse with lysosomes to degrade the sequestered contents. Autophagy serves to maintain cellular homeostasis. There is a close relationship between autophagy and tumor progression, which provides opportunities for the development of anticancer therapeutics that target the autophagy pathway. In this review, we analyze the effects of human papillomavirus (HPV) E5, E6, and E7 oncoproteins on autophagy processes in cervical cancer development. Inhibition of the expression or the activity of E5, E6, and E7 can induce autophagy in cells expressing HPV oncogenes. Thus, E5, E6, and E7 oncoproteins target autophagy during HPV-associated carcinogenesis. Furthermore, noncoding RNA (ncRNA) expression profiling in cervical cancer has allowed the identification of autophagy-related ncRNAs associated with HPV. Autophagy-related genes are essential drivers of autophagy and are regulated by ncRNAs. We review the existing evidence regarding the role of autophagy-related proteins, the function of HPV E5, E6, and E7 oncoproteins, and the effects of noncoding RNA on autophagy regulation in the setting of cervical carcinogenesis. By characterizing the mechanisms behind the dysregulation of these critical factors and their impact on host cell autophagy, we advance understanding of the relationship between autophagy and progression from HPV infection to cervical cancer, and highlight pathways that can be targeted in preventive and therapeutic strategies against cervical cancer.


Assuntos
Proteínas Oncogênicas Virais , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Autofagia/genética , Carcinogênese/genética , Feminino , Humanos , Proteínas Oncogênicas Virais/metabolismo , Papillomaviridae/genética , Proteínas E7 de Papillomavirus/genética , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/patologia , RNA não Traduzido/genética , Neoplasias do Colo do Útero/patologia
6.
J Fungi (Basel) ; 8(1)2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-35049997

RESUMO

In fungi, metals are associated with the expression of virulence factors. However, it is unclear whether the uptake of metals affects their pathogenicity. This study aimed to evaluate the effect of iron/copper in modulating pathogenicity and proteomic response in two clinical isolates of C. neoformans with high and low pathogenicity. METHODS: In both isolates, the effect of 50 µM iron and 500 µM copper on pathogenicity, capsule induction, and melanin production was evaluated. We then performed a quantitative proteomic analysis of cytoplasmic extracts exposed to that combination. Finally, the effect on pathogenicity by iron and copper was evaluated in eight additional isolates. RESULTS: In both isolates, the combination of iron and copper increased pathogenicity, capsule size, and melanin production. Regarding proteomic data, proteins with increased levels after iron and copper exposure were related to biological processes such as cell stress, vesicular traffic (Ap1, Vps35), cell wall structure (Och1, Ccr4, Gsk3), melanin biosynthesis (Hem15, Mln2), DNA repair (Chk1), protein transport (Mms2), SUMOylation (Uba2), and mitochondrial transport (Atm1). Increased pathogenicity by exposure to metal combination was also confirmed in 90% of the eight isolates. CONCLUSIONS: The combination of these metals enhances pathogenicity and increases the abundance of proteins related to the main virulence factors.

7.
mBio ; 13(1): e0387321, 2021 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35164565

RESUMO

Phosphatidylinositol phosphates are key phospholipids with a range of regulatory roles, including membrane trafficking and cell polarity. Phosphatidylinositol-4-phosphate [PI(4)P] at the Golgi apparatus is required for the budding-to-filamentous-growth transition in the human-pathogenic fungus Candida albicans; however, the role of plasma membrane PI(4)P is unclear. We have investigated the importance of this phospholipid in C. albicans growth, stress response, and virulence by generating mutant strains with decreased levels of plasma membrane PI(4)P, via deletion of components of the PI-4-kinase complex, i.e., Efr3, Ypp1, and Stt4. The amounts of plasma membrane PI(4)P in the efr3Δ/Δ and ypp1Δ/Δ mutants were ∼60% and ∼40%, respectively, of that in the wild-type strain, whereas it was nearly undetectable in the stt4Δ/Δ mutant. All three mutants had reduced plas7ma membrane phosphatidylserine (PS). Although these mutants had normal yeast-phase growth, they were defective in filamentous growth, exhibited defects in cell wall integrity, and had an increased exposure of cell wall ß(1,3)-glucan, yet they induced a range of hyphal-specific genes. In a mouse model of hematogenously disseminated candidiasis, fungal plasma membrane PI(4)P levels directly correlated with virulence; the efr3Δ/Δ mutant had wild-type virulence, the ypp1Δ/Δ mutant had attenuated virulence, and the stt4Δ/Δ mutant caused no lethality. In the mouse model of oropharyngeal candidiasis, only the ypp1Δ/Δ mutant had reduced virulence, indicating that plasma membrane PI(4)P is less important for proliferation in the oropharynx. Collectively, these results demonstrate that plasma membrane PI(4)P levels play a central role in filamentation, cell wall integrity, and virulence in C. albicans. IMPORTANCE While the PI-4-kinases Pik1 and Stt4 both produce PI(4)P, the former generates PI(4)P at the Golgi apparatus and the latter at the plasma membrane, and these two pools are functionally distinct. To address the importance of plasma membrane PI(4)P in Candida albicans, we generated deletion mutants of the three putative plasma membrane PI-4-kinase complex components and quantified the levels of plasma membrane PI(4)P in each of these strains. Our work reveals that this phosphatidylinositol phosphate is specifically critical for the yeast-to-hyphal transition, cell wall integrity, and virulence in a mouse systemic infection model. The significance of this work is in identifying a plasma membrane phospholipid that has an infection-specific role, which is attributed to the loss of plasma membrane PI(4)P resulting in ß(1,3)-glucan unmasking.


Assuntos
Candida albicans , Candidíase , Animais , Camundongos , Candida albicans/genética , Candidíase/microbiologia , Membrana Celular/metabolismo , Parede Celular/metabolismo , Modelos Animais de Doenças , Proteínas Fúngicas/genética , Hifas , Fosfatos de Fosfatidilinositol/metabolismo
8.
Methods Mol Biol ; 2174: 13-17, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32813241

RESUMO

Prostate cancer is one of the main causes of cancer and the sixth cause of death among men worldwide. One of the major challenges in prostate cancer research is cell heterogeneity defined as the different genomic and phenotypic characteristics in each individual cell making more difficult to assess the proper prostate cancer diagnosis and therapy. Tumor 3D spatial arrangement allow a strong interaction between the different cellular lineages and components which modulate cell proliferation, differentiation, and morphology. Prostate cancer spheroids are a cellular model which is capable to mimic the mechanical tensions of tumor tissue, providing a more representative pathophysiological model than the use of conventional 2D culture. Here, we describe a protocol to develop a 3D model of spheroids using prostate cancer cell lines (LNCaP, PC3, VCaP) which can be used to improve research considering tumoral heterogeneity role in cancer development, prognosis, and therapy.


Assuntos
Neoplasias da Próstata/patologia , Esferoides Celulares/patologia , Linhagem Celular Tumoral , Humanos , Masculino , Células PC-3
9.
Artigo em Inglês | MEDLINE | ID: mdl-33046489

RESUMO

Invasive fungal diseases represent an unmet clinical need that could benefit from novel immunotherapeutic approaches. Host pattern recognition receptors (e.g., Toll-like receptors, C-type lectins, or scavenger receptors) that sense conserved fungal cell wall constituents may provide suitable immunotherapeutic antifungal agents. Thus, we explored the therapeutic potential of the lymphocyte class I scavenger receptor CD5, a nonredundant component of the antifungal host immune response that binds to fungal ß-glucans. Antifungal properties of the soluble ectodomain of human CD5 (shCD5) were assessed in vivo in experimental models of systemic fungal infection induced by pathogenic species (Candida albicans and Cryptococcus neoformans). In vitro mechanistic studies were performed by means of fungus-spleen cell cocultures. shCD5-induced survival of lethally infected mice was dose and time dependent and concomitant with reduced fungal load and increased leukocyte infiltration in the primary target organ. Additive effects were observed in vivo after shCD5 was combined with suboptimal doses of fluconazole. Ex vivo addition of shCD5 to fungus-spleen cell cocultures increased the release of proinflammatory cytokines involved in antifungal defense (tumor necrosis factor alpha and gamma interferon) and reduced the number of viable C. albicans organisms. The results prompt further exploration of the adjunctive therapeutic potential of shCD5 in severe invasive fungal diseases.


Assuntos
Cryptococcus neoformans , Micoses , Animais , Antifúngicos/farmacologia , Candida albicans , Linfócitos , Camundongos , Receptores Depuradores
10.
Rev Invest Clin ; 72(4): 188-197, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33064686

RESUMO

Optimal function of the immune system allows the recognition and elimination of infected and tumor cells. However, these cells can develop mechanisms to evade the cellular immune response. In human papillomavirus (HPV) infection, dysregulation of major histocompatibility complex Class I molecules and other components of the innate immune system promote the survival of infected cells by allowing the infection to persist which, in turn, favors the development of cancer. Further, tumor cells possess inherent mechanisms designed to block the recognition and activation of cytotoxic lymphocytes: particularly, HPV proteins such as E1 and E2 and oncoproteins E5, E6, and E7 that inhibit immune mechanisms and/or stimulate the expression of immunosuppressive cytokines. These mechanisms include a decrease in receptor activation and costimulating molecules on the surface of immune cells, as well as the constitutive expression of molecules that inhibit their function, which allow HPV persistence and tumor progression. Immunotherapy-based therapeutic options are positioned as excellent candidates for the treatment of cervical cancer.


Assuntos
Antígenos de Histocompatibilidade Classe I , Proteínas Oncogênicas Virais , Infecções por Papillomavirus , Neoplasias do Colo do Útero/imunologia , Feminino , Humanos , Imunoterapia , Proteínas E7 de Papillomavirus , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/terapia , Neoplasias do Colo do Útero/virologia
11.
Genes (Basel) ; 11(9)2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32911741

RESUMO

BACKGROUND: Serine Threonine Kinase 11 (STK11), also known as LKB1, is a tumor suppressor gene that regulates several biological processes such as apoptosis, energetic metabolism, proliferation, invasion, and migration. During malignant progression, different types of cancer inhibit STK11 function by mutation or epigenetic inactivation. In Head and Neck Cancer, it is unclear what mechanism is involved in decreasing STK11 levels. Thus, the present work aims to determine whether STK11 expression might be regulated through epigenetic or post-translational mechanisms. METHODS: Expression levels and methylation status for STK11 were analyzed in 59 cases of head and neck cancer and 10 healthy tissue counterparts. Afterward, we sought to identify candidate miRNAs exerting post-transcriptional regulation of STK11. Then, we assessed a luciferase gene reporter assay to know if miRNAs directly target STK11 mRNA. The expression levels of the clinical significance of mir-100-3p, -5p, and STK11 in 495 HNC specimens obtained from the TCGA database were further analyzed. Finally, the Kaplan-Meier method was used to estimate the prognostic significance of the miRNAs for Overall Survival, and survival curves were compared through the log-rank test. RESULTS: STK11 was under-expressed, and its promoter region was demethylated or partially methylated. miR-17-5p, miR-106a-5p, miR-100-3p, and miR-100-5p could be negative regulators of STK11. Our experimental data suggested evidence that miR-100-3p and -5p were over-expressed in analyzed tumor patient samples. Luciferase gene reporter assay experiments showed that miR-100-3p targets and down-regulates STK11 mRNA directly. With respect to overall survival, STK11 expression level was significant for predicting clinical outcomes. CONCLUSION: This is, to our knowledge, the first report of miR-100-3p targeting STK11 in HNC. Together, these findings may support the importance of regulation of STK11 through post-transcriptional regulation in HNC and the possible contribution to the carcinogenesis process in this neoplasia.


Assuntos
Biomarcadores Tumorais/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço/patologia , MicroRNAs/genética , Proteínas Serina-Treonina Quinases/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Quinases Proteína-Quinases Ativadas por AMP , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Movimento Celular , Proliferação de Células , Feminino , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Proteínas Serina-Treonina Quinases/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Taxa de Sobrevida , Células Tumorais Cultivadas
12.
Rev. invest. clín ; 72(4): 188-197, Jul.-Aug. 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1251856

RESUMO

ABSTRACT Optimal function of the immune system allows the recognition and elimination of infected and tumor cells. However, these cells can develop mechanisms to evade the cellular immune response. In human papillomavirus (HPV) infection, dysregulation of major histocompatibility complex Class I molecules and other components of the innate immune system promote the survival of infected cells by allowing the infection to persist which, in turn, favors the development of cancer. Further, tumor cells possess inherent mechanisms designed to block the recognition and activation of cytotoxic lymphocytes: particularly, HPV proteins such as E1 and E2 and oncoproteins E5, E6, and E7 that inhibit immune mechanisms and/or stimulate the expression of immunosuppressive cytokines. These mechanisms include a decrease in receptor activation and costimulating molecules on the surface of immune cells, as well as the constitutive expression of molecules that inhibit their function, which allow HPV persistence and tumor progression. Immunotherapy-based therapeutic options are positioned as excellent candidates for the treatment of cervical cancer.


Assuntos
Humanos , Feminino , Antígenos de Histocompatibilidade Classe I , Neoplasias do Colo do Útero/imunologia , Proteínas Oncogênicas Virais , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/terapia , Neoplasias do Colo do Útero/virologia , Proteínas E7 de Papillomavirus , Imunoterapia
13.
J Cancer ; 11(16): 4754-4761, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32626522

RESUMO

The mechanisms of signal transduction by interferon-tau (IFN-τ) are widely known during the gestation of ruminants. In trophoblast cells, IFN-τ involves the activation of the JAK-STAT pathway, and it can have effects on other cell types, such as tumor cells. Here we report that the HPV16-positive BMK-16/myc cell treated with ovine IFN-τ, results in the activation of the canonical JAK-STAT and non-canonical JAK-STAT pathway. The MAPK signaling pathway was activated, we detected the proteins MEK1, MEK2, Raf1, STAT3, STA4, STAT5 and STAT6. Moreover, IFN-τ induced the expression of MHC Class I, MX and IP10 in the tumor cells and this response may be associated with the viral replication and with the anti-proliferative and the immunoregulatory effects of IFN-τ.

14.
Rev Iberoam Micol ; 37(2): 63-64, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32546314

RESUMO

BACKGROUND: Rhodotorula species were traditionally considered non-virulent environmental microorganisms, but are nowadays considered important human pathogens, especially in immunocompromised individuals. CASE REPORT: We present the case of a 73 year-old man with diarrhea, anorexia and fever. In the blood analyses, both aerobic blood culture bottles yielded the growth of Rhodotorula dairenensis. The MALDI-TOF MS score was inadequate to provide an identification, which was achieved by means of molecular techniques. Treatment with an echinocandin was started, but the patient died. CONCLUSIONS: Basidiomycetous yeast genera such as Rhodotorula can cause invasive and severe infections, e.g., fungemia, especially in patients with central venous catheter or another indwelling device.


Assuntos
Adenocarcinoma/complicações , Neoplasias do Colo/complicações , Fungemia/microbiologia , Rhodotorula/isolamento & purificação , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/secundário , Corticosteroides/administração & dosagem , Idoso , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Caspofungina/uso terapêutico , Cetuximab/administração & dosagem , Cetuximab/efeitos adversos , Neoplasias do Colo/tratamento farmacológico , Evolução Fatal , Fungemia/complicações , Fungemia/tratamento farmacológico , Humanos , Hospedeiro Imunocomprometido , Obstrução Intestinal/etiologia , Irinotecano/administração & dosagem , Irinotecano/efeitos adversos , Masculino , Neoplasias Peritoneais/complicações
15.
Sci Rep ; 10(1): 3256, 2020 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-32094378

RESUMO

Malignant transformation and progression in cancer is associated with the altered expression of multiple miRNAs, which are considered as post-transcriptional regulators of genes participating in various cellular processes. Although, it has been proposed that miR-23b-3p acts as a tumor suppressor in cervical cancer (CC), not all the pathways through which it alters the cellular processes have been described. The present study examines whether miR-23b-3p directly represses the c-Met expression and that consequently modifies the proliferation, migration and invasion of C33A and CaSki cells. c-Met has five microRNA response elements (MREs) for miR-23b-3p in the 3'-UTR region. The ectopic overexpression of miR-23b-3p significantly reduces c-Met expression in C33A and CaSki cells. The overexpression of miR-23b-3p reduces proliferation, migration and invasion of CaSki cells and the proliferation and invasion in C33A cells. In CaSki cells, the activation of Gab1 and Fak, downstream of c-Met, is reduced in response to the overexpression of miR-23b-3p. Together, the results in the present study indicate that miR-23b-3p is a tumor suppressor that modulates the progression of CC via post-transcriptional regulation of the c-Met oncogene.


Assuntos
Regulação Neoplásica da Expressão Gênica , Proteínas Proto-Oncogênicas c-met/metabolismo , Neoplasias do Colo do Útero/metabolismo , Regiões 3' não Traduzidas , Algoritmos , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Humanos , MicroRNAs/metabolismo , Invasividade Neoplásica , Metástase Neoplásica , Elementos de Resposta , Neoplasias do Colo do Útero/patologia
16.
Cancer Cell Int ; 19: 214, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31427899

RESUMO

BACKGROUND: Gene expression profiles have demonstrated that miR-21 expression is altered in almost all types of cancers and it has been classified as an oncogenic microRNA. Persistent HPV infection is the main etiologic agent in cervical cancer and induces genetic instability, including disruption of microRNA gene expression. In the present study, we analyzed the underlying mechanism of how AP-1 transcription factor can active miR-21 gene expression in cervical cancer cells. METHODS: To identify that c-Fos and c-Jun regulate the expression of miR-21 we performed RT-qPCR and western blot assays. We analyzed the interaction of AP-1 with miR-21 promoter by EMSA and ChIP assays and determined the mechanism of its regulation by reporter construct plasmids. We identified the nuclear translocation of c-Fos and c-Jun by immunofluorescence microscopy assays. RESULTS: We demonstrated that c-Fos and c-Jun proteins are expressed and regulate the expression of miR-21 in cervical cancer cells. DNA sequence analysis revealed the presence of AP-1 DNA-binding sites in the human miR-21 promoter region. EMSA analyses confirmed the interactions of the miR-21 upstream transcription factor AP-1. ChIP assays further showed the binding of c-Fos to AP-1 sequences from the miR-21 core promoter in vivo. Functional analysis of AP-1 sequences of miR-21 in reporter plasmids demonstrated that these sequences increase the miR-21 promoter activation. CONCLUSIONS: Our findings suggest a physical interaction and functional cooperation between AP-1 transcription factor in the miR-21 promoter and may explain the effect of AP-1 on miR-21 gene expression in cervical cancer cells.

17.
Int J Oncol ; 55(3): 555-569, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31322194

RESUMO

Gastrokine 1 (GKN1) is a protein expressed on the surface mucosa cells of the gastric antrum and fundus, which contributes to maintaining gastric homeostasis, inhibits inflammation and is a tumor suppressor. The expression of GKN1 decreases in mucosa that are either inflamed or infected by Helicobacter pylori, and is absent in gastric cancer. The measurement of circulating GKN1 concentration, the protein itself, or the mRNA in gastric tissue may be of use for the early diagnosis of cancer. The mechanisms that modulate the deregulation or silencing of GKN1 expression have not been completely described. The modification of histones, methylation of the GKN1 promoter, or proteasomal degradation of the protein have been detected in some patients; however, these mechanisms do not completely explain the absence of GKN1 or the reduction in GKN1 levels. Only NKX6.3 transcription factor has been shown to be a positive modulator of GKN1 transcription, although others also have an affinity with sequences in the promoter of this gene. While microRNAs (miRNAs) are able to directly or indirectly regulate the expression of genes at the post­transcriptional level, the involvement of miRNAs in the regulation of GKN1 has not been reported. The present review analyzes the information reported on the determination of GKN1 expression and the regulation of its expression at the transcriptional, post­transcriptional and post­translational levels; it proposes an integrated model that incorporates the regulation of GKN1 expression via transcription factors and miRNAs in H. pylori infection.


Assuntos
Regulação para Baixo , Infecções por Helicobacter/diagnóstico , Hormônios Peptídicos/genética , Hormônios Peptídicos/metabolismo , Neoplasias Gástricas/diagnóstico , Metilação de DNA , Detecção Precoce de Câncer , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Infecções por Helicobacter/genética , Infecções por Helicobacter/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , MicroRNAs/genética , Regiões Promotoras Genéticas , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
18.
Front Microbiol ; 10: 1585, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31354675

RESUMO

The pathogenic yeast Candida glabrata has become a public health issue due to the increasing number of echinocandin resistant clinical strains reported. In this study, acquisition and development of resistance to this antifungal class were studied in serial C. glabrata isolates from five patients admitted in two Spanish hospitals with a resistant profile against echinocandins associated with different mutations in hot-spot 1 of FKS2 gene. For two of these patients susceptible FKS wild-type isolates obtained prior to resistant ones were also investigated. Isolates were genotyped using multilocus sequence typing and microsatellite length polymorphism techniques, which yielded comparable results. Susceptible and resistant isolates from the same patient had the same genotype, being sequence type (ST) 3 the most prevalent among them. Isolates with different FKS mutations but the same ST were present in the same patient. MSH2 gene alterations were also studied to investigate their correlation with antifungal resistance acquisition but no association was found with antifungal resistance nor with specific genotypes. In vitro exposure to increasing concentrations of micafungin to susceptible isolates developed colonies carrying FKS mutations in agar plates containing a minimum concentration of 0.06 mg/L of micafungin after less than 48 h of exposure. We investigated the correlation between development of resistance and genotype in a set of susceptible strains after being in vitro exposed to micafungin and anidulafungin but no correlation was found. Mutant prevention concentration values and spontaneous growth frequencies after selection with both echinocandins were statistically similar, although FKS mutant colonies were more abundant after micafungin exposure (p < 0.001). Mutation S663P and F659 deletion were the most common ones found after selection with both echinocandins.

19.
Mol Oncol ; 13(5): 1249-1267, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30938061

RESUMO

Radioresistance of tumor cells gives rise to local recurrence and disease progression in many patients. MicroRNAs (miRNAs) are master regulators of gene expression that control oncogenic pathways to modulate the radiotherapy response of cells. In the present study, differential expression profiling assays identified 16 deregulated miRNAs in acquired radioresistant breast cancer cells, of which miR-122 was observed to be up-regulated. Functional analysis revealed that miR-122 has a role as a tumor suppressor in parental cells by decreasing survival and promoting radiosensitivity. However, in radioresistant cells, miR-122 functions as an oncomiR by promoting survival. The transcriptomic landscape resulting from knockdown of miR-122 in radioresistant cells showed modulation of the ZNF611, ZNF304, RIPK1, HRAS, DUSP8 and TNFRSF21 genes. Moreover, miR-122 and the set of affected genes were prognostic factors in breast cancer patients treated with radiotherapy. Our data indicate that up-regulation of miR-122 promotes cell survival in acquired radioresistant breast cancer and also suggest that miR-122 differentially controls the response to radiotherapy by a dual function as a tumor suppressor an and oncomiR dependent on cell phenotype.


Assuntos
Neoplasias da Mama , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Genes Supressores de Tumor , MicroRNAs/biossíntese , RNA Neoplásico/biossíntese , Tolerância a Radiação , Regulação para Cima/efeitos da radiação , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Neoplasias da Mama/radioterapia , Feminino , Humanos , Células MCF-7 , MicroRNAs/genética , Proteínas de Neoplasias , RNA Neoplásico/genética
20.
Expert Rev Anti Infect Ther ; 17(4): 295-305, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30922129

RESUMO

BACKGROUND: Candida auris is an emerging, multidrug-resistant yeast causing hospital outbreaks. This study describes the first 24 months of the ongoing C. auris outbreak in our hospital and analyzes predisposing factors to C. auris candidemia/colonization. RESEARCH DESIGN AND METHODS: A 12-month prospective, case-controlled study was performed including a total of 228 patients (114 colonized/candidemia and 114 controls). Data from the first 79 candidemia episodes and 738 environmental samples were also analyzed. Definitive C. auris identification was performed by ITS sequencing. Antifungal susceptibility was carried out by EUCAST methodology. RESULTS: Polytrauma (32%), cardiovascular disease (25%), and cancer (17%) were the most common underlying condition in colonized/candidemia patients. Indwelling CVC (odds ratio {OR}, 13.48), parenteral nutrition (OR, 3.49), and mechanical ventilation (OR, 2.43) remained significant predictors of C. auris colonization/candidemia. C. auris was most often isolated on sphygmomanometer cuffs (25%) patient tables (10.2%), keyboards (10.2%), and infusion pumps (8.2%). All isolates were fully resistant to fluconazole (MICs >64 mg/L) and had significantly reduced susceptibility to voriconazole (GM, 1.8 mg/L). CONCLUSIONS: Predictor conditions to C. auris colonization/candidemia are similar to other Candida species. C. auris colonizes multiple patient's environment surfaces. All isolates are resistant to fluconazole and had significant reduced susceptibility to voriconazole.


Assuntos
Antifúngicos/administração & dosagem , Candida/isolamento & purificação , Candidemia/tratamento farmacológico , Surtos de Doenças , Adulto , Idoso , Antifúngicos/farmacologia , Candidemia/microbiologia , Estudos de Casos e Controles , Estado Terminal , Farmacorresistência Viral , Feminino , Fluconazol/farmacologia , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Voriconazol/farmacologia
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