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1.
Nucleic Acids Res ; 49(20): 11690-11707, 2021 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-34725692

RESUMO

Loss of telomeric DNA leads to telomere uncapping, which triggers a persistent, p53-centric DNA damage response that sustains a stable senescence-associated proliferation arrest. Here, we show that in normal cells telomere uncapping triggers a focal telomeric DNA damage response accompanied by a transient cell cycle arrest. Subsequent cell division with dysfunctional telomeres resulted in sporadic telomeric sister chromatid fusions that gave rise to next-mitosis genome instability, including non-telomeric DNA lesions responsible for a stable, p53-mediated, senescence-associated proliferation arrest. Unexpectedly, the blocking of Rad51/RPA-mediated homologous recombination, but not non-homologous end joining (NHEJ), prevented senescence despite multiple dysfunctional telomeres. When cells approached natural replicative senescence, interphase senescent cells displayed genome instability, whereas near-senescent cells that underwent mitosis despite the presence of uncapped telomeres did not. This suggests that these near-senescent cells had not yet acquired irreversible telomeric fusions. We propose a new model for telomere-initiated senescence where tolerance of telomere uncapping eventually results in irreversible non-telomeric DNA lesions leading to stable senescence. Paradoxically, our work reveals that senescence-associated tumor suppression from telomere shortening requires irreversible genome instability at the single-cell level, which suggests that interventions to repair telomeres in the pre-senescent state could prevent senescence and genome instability.


Assuntos
Instabilidade Genômica , Recombinação Homóloga , Encurtamento do Telômero/genética , Células Cultivadas , Dano ao DNA , Reparo do DNA por Junção de Extremidades , Humanos , Rad51 Recombinase/metabolismo
2.
EMBO Rep ; 21(10): e50718, 2020 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-32785991

RESUMO

Senescent cells display senescence-associated (SA) phenotypic programs such as stable proliferation arrest (SAPA) and a secretory phenotype (SASP). Senescence-inducing persistent DNA double-strand breaks (pDSBs) cause an immediate DNA damage response (DDR) and SAPA, but the SASP requires days to develop. Here, we show that following the immediate canonical DDR, a delayed chromatin accumulation of the ATM and MRN complexes coincides with the expression of SASP factors. Importantly, histone deacetylase inhibitors (HDACi) trigger SAPA and SASP in the absence of DNA damage. However, HDACi-induced SASP also requires ATM/MRN activities and causes their accumulation on chromatin, revealing a DNA damage-independent, non-canonical DDR activity that underlies SASP maturation. This non-canonical DDR is required for the recruitment of the transcription factor NF-κB on chromatin but not for its nuclear translocation. Non-canonical DDR further does not require ATM kinase activity, suggesting structural ATM functions. We propose that delayed chromatin recruitment of SASP modulators is the result of non-canonical DDR signaling that ensures SASP activation only in the context of senescence and not in response to transient DNA damage-induced proliferation arrest.


Assuntos
Senescência Celular , NF-kappa B , Senescência Celular/genética , Cromatina/genética , Dano ao DNA , NF-kappa B/metabolismo , Transdução de Sinais
3.
Int J Cancer ; 141(11): 2318-2328, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-28779483

RESUMO

The purpose of this study was to determine the prognostic value and oncogenic pathways associated to miRNA expression in squamous cell carcinoma of the oral tongue and to link these miRNA candidates with potential gene targets. We performed a miRNA screening within our institutional cohort (n = 58 patients) and reported five prognostic targets including a cluster of four co-expressed miRNAs (miR-18a, miR-92a, miR-103, and miR-205). Multivariate analysis showed that expression of miR-548b (p = 0.007) and miR-18a (p = 0.004, representative of co-expressed miRNAs) are independent prognostic markers for squamous cell carcinoma of the oral tongue. These findings were validated in The Cancer Genome Atlas (TCGA) cohort (n = 131) for both miRNAs (miR-548b: p = 0.027; miR-18a: p = 0.001). Bioinformatics analysis identified PTEN and ACTN4 as direct targets of the four co-expressed miRNAs and miR-548b, respectively. Correlations between the five identified miRNAs and their respective targeted genes were validated in the two merged cohorts and were concordantly significant (miR-18a/PTEN: p < 0.0001; miR-92a/PTEN: p = 0.0008; miR-103/PTEN: p = 0.008; miR-203/PTEN: p = 0.019; miR-548b/ACTN4: p = 0.009).


Assuntos
Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/patologia , Regulação Neoplásica da Expressão Gênica/genética , Neoplasias de Cabeça e Pescoço/patologia , MicroRNAs/genética , Neoplasias da Língua/patologia , Actinina/metabolismo , Idoso , Área Sob a Curva , Biomarcadores Tumorais/análise , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/mortalidade , Feminino , Imunofluorescência , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/mortalidade , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , PTEN Fosfo-Hidrolase/metabolismo , Prognóstico , Curva ROC , Reação em Cadeia da Polimerase em Tempo Real , Carcinoma de Células Escamosas de Cabeça e Pescoço , Neoplasias da Língua/genética , Neoplasias da Língua/mortalidade
4.
Front Cell Dev Biol ; 12: 1368711, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38946802

RESUMO

Malignant Melanoma that resists immunotherapy remains the deadliest form of skin cancer owing to poor clinically lasting responses. Alternative like genotoxic or targeted chemotherapy trigger various cancer cell fates after treatment including cell death and senescence. Senescent cells can be eliminated using senolytic drugs and we hypothesize that the targeted elimination of therapy-induced senescent melanoma cells could complement both conventional and immunotherapies. We utilized a panel of cells representing diverse mutational background relevant to melanoma and found that they developed distinct senescent phenotypes in response to treatment. A genotoxic combination therapy of carboplatin-paclitaxel or irradiation triggered a mixed response of cell death and senescence, irrespective of BRAF mutation profiles. DNA damage-induced senescent melanoma cells exhibited morphological changes, residual DNA damage, and increased senescence-associated secretory phenotype (SASP). In contrast, dual targeted inhibition of Braf and Mek triggered a different mixed cell fate response including senescent-like and persister cells. While persister cells could reproliferate, senescent-like cells were stably arrested, but without detectable DNA damage and senescence-associated secretory phenotype. To assess the sensitivity to senolytics we employed a novel real-time imaging-based death assay and observed that Bcl2/Bcl-XL inhibitors and piperlongumine were effective in promoting death of carboplatin-paclitaxel and irradiation-induced senescent melanoma cells, while the mixed persister cells and senescent-like cells resulting from Braf-Mek inhibition remained unresponsive. Interestingly, a direct synergy between Bcl2/Bcl-XL inhibitors and Braf-Mek inhibitors was observed when used out of the context of senescence. Overall, we highlight diverse hallmarks of melanoma senescent states and provide evidence of context-dependent senotherapeutics that could reduce treatment resistance while also discussing the limitations of this strategy in human melanoma cells.

5.
Blood Cancer J ; 14(1): 96, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38871704

RESUMO

Childhood acute lymphoblastic leukemia (cALL) survivors suffer early-onset chronic diseases classically associated with aging. Normal aging is accompanied by organ dysfunctions, including immunological ones. We hypothesize that thymic immunosenescence occurs in cALL survivors and that its severity may correlate with early-onset chronic diseases. The PETALE study is a cALL survivor cohort with an extensive cardiovascular and metabolic evaluation. The thymic immunosenescence biomarker, signal joint T-cell receptor excision circles (TREC), was evaluated and was highly correlated with age in healthy participants (n = 281) and cALL survivors (n = 248). We observed a systematic thymic immunoage accentuation in each cALL survivor compared to controls ranging from 5.9 to 88.3 years. The immunoage gain was independent of age at diagnosis and treatment modalities and was more severe for females. Thymic aging was associated with several pathophysiological parameters, was greater in survivors suffering from metabolic syndrome, but there was no significant association with global physical condition. The decrease in TREC was independent from blood cell counts, which were normal, suggesting a segmental aging of the thymic compartment. Indeed, increased plasmatic T cell regulatory cytokines IL-6, IL-7 and GM-CSF accompanied high immunoage gain. Our data reveal that cALL or its treatment trigger a rapid immunoage gain followed by further gradual thymic immunosenescence, similar to normal aging. This leads to an enduring shift in accentuated immunoage compared to chronological age. Thus, accentuated thymic immunosenescence is a hallmark of cALL survivorship and TREC levels could be useful immunosenescence biomarkers to help monitoring the health of cancer survivors.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras , Timo , Humanos , Feminino , Masculino , Criança , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Adolescente , Adulto , Timo/patologia , Timo/imunologia , Pré-Escolar , Adulto Jovem , Idoso , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Sobreviventes de Câncer , Imunossenescência , Sobrevivência
6.
Oral Oncol ; 136: 106273, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36521381

RESUMO

The inclusion of depth of invasion (DOI) in the American Joint Committee on Cancer's staging system for oral cavity squamous cell carcinoma (SCC) has major clinical impacts. Recent studies have evaluated the reliability of imaging modalities and biopsy techniques to measure DOI preoperatively. The objective of this systematic review and meta-analysis was to comprehensively include all previously described methods to measure preoperative DOI in oral tongue SCC (OTSCC) and to compare their reliability. A systematic review was conducted on PubMed, Embase and Cochrane according to the PRISMA guidelines. Studies that evaluated the reliability of DOI measured on biopsy or imaging (rDOI) by comparing it to DOI on histopathology (pDOI) were included for extraction. A meta-analysis was conducted to obtain pooled correlation coefficients for each imaging modality. The pooled correlation coefficients between rDOI and pDOI were 0.86 (CI95% = [0.82-0.88]) and 0.80 (CI95% = [0.70-0.87]) for magnetic resonance imaging (MRI) studies and computed tomography (CT) studies, respectively. For ultrasound (US), the correlation coefficient could only be measured by including studies which measured not only DOI but also tumor thickness. It was 0.89 (CI95%= [0.82-0.94]). Overall, MRI is the better studied modality. It has a good reliability to measure preoperative rDOI in OTSCC. CT is less studied but appears to be less reliable. US cannot be compared to these imaging modality as it has been used more often to measure TT than DOI.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias da Língua , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Carcinoma de Células Escamosas/patologia , Neoplasias da Língua/patologia , Reprodutibilidade dos Testes , Estadiamento de Neoplasias , Invasividade Neoplásica/patologia , Neoplasias de Cabeça e Pescoço/patologia , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos
7.
Laryngoscope Investig Otolaryngol ; 7(4): 963-969, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36000064

RESUMO

Objective: To measure and visualize aerosol generation during ear, nose, and throat (ENT) exam and flexible laryngoscopy, as safety recommendations are currently to defer routine and low-priority examinations. Methods: Aerosols generated during ENT examination and flexible laryngoscopy were quantified by laser aerosol spectrometry and visualized live by high-speed imaging during those procedures for three participants who were tested three times for each test. Results: Routine ENT examination and flexible laryngoscopy produce aerosols at levels comparable to normal breathing and speech. Conclusion: During ENT examination and flexible laryngoscopy, the practitioner should wear a surgical mask and potentially contaminated surfaces should be cleaned after the procedure. For flexible laryngoscopy, it is recommended in addition that the patient wear a mask over the mouth in case the procedure induces a sneeze. The time during which the patient is unmasked should be minimized. In these settings, the risk to the practitioner is minimal unless the patient is sneezing or symptomatic. Level of Evidence: 1.

8.
Front Microbiol ; 13: 1062113, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36620055

RESUMO

Lactic acid bacteria, including the microorganisms formerly designated as Lactobacillus, are the major representatives of Live Biotherapeutic Microorganisms (LBM) when used for therapeutic purposes. However, in most cases, the mechanisms of action remain unknown. The antifungal potential of LBM has already been demonstrated using preclinical models (cell cultures, laboratory animals). Understanding their mechanisms of action is strategic for the development of new therapeutics for humans. Here, Caenorhabditis elegans was used as an in vivo model to analyze pro-longevity, anti-aging and anti-candidiasis effects of the LBM Lacticaseibacillus rhamnosus (formerly Lactobacillus rhamnosus) Lcr35®. A high-throughput transcriptomic analysis revealed a specific response of C. elegans depending on whether it is in the presence of the LBM L. rhamnosus Lcr35® (structural response), the yeast Candida albicans (metabolic response) or both (structural and metabolic responses) in a preventive and a curative conditions. Studies on C. elegans mutants demonstrated that the p38 MAPK (sek-1, skn-1) and the insulin-like (daf-2, daf-16) signaling pathways were involved in the extended lifespan provided by L. rhamnosus Lcr35® strain whereas the JNK pathway was not involved (jnk-1). In addition, the anti C. albicans effect of the bacterium requires the daf-16 and sek-1 genes while it is independent of daf-2 and skn-1. Moreover, the anti-aging effect of Lcr35®, linked to the extension of longevity, is not due to protection against oxidative stress (H2O2). Taken together, these results formally show the involvement of the p38 MAP kinase and insulin-like signaling pathways for the longevity extension and anti-Candida albicans properties of Lcr35® with, however, differences in the genes involved. Overall, these findings provide new insight for understanding the mechanisms of action of a probiotic strain with antimicrobial potential.

9.
Sci Rep ; 11(1): 12753, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-34140574

RESUMO

Germline single nucleotide polymorphisms in the promoter region of the DCBLD1 gene are associated with non-smoking cases of both non-small cell lung carcinoma (NSCLC) and human papillomavirus-negative head and neck cancer. However the clinical relevance and function of DCBLD1 remain unclear. This multicenter retrospective study was designed to evaluate the prognostic value and function of DCBLD1 in the four main solid cancers: NSCLC, invasive breast carcinoma, colorectal adenocarcinoma and prostate adenocarcinoma. We included the following cohorts: GSE81089 NSCLC, METABRIC invasive breast carcinoma, GSE14333 colorectal adenocarcinoma, GSE70770 prostate adenocarcinoma and The Cancer Genome Atlas (TCGA) Firehose Legacy cohorts of all four cancers. DCBLD1 gene expression was associated with a worse overall survival in multivariate analyses for both NSCLC cohorts (TCGA: P = 0.03 and GSE81089: P = 0.04) and both invasive breast carcinoma cohorts (TCGA: P = 0.02 and METABRIC: P < 0.001). Patients with high DCBLD1 expression showed an upregulation of the integrin signaling pathway in comparison to those with low DCBLD1 expression in the TCGA NSCLC cohort (FDR = 5.16 × 10-14) and TCGA invasive breast carcinoma cohort (FDR = 1.94 × 10-05).


Assuntos
Neoplasias da Mama/patologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Integrinas/metabolismo , Neoplasias Pulmonares/patologia , Proteínas de Membrana/genética , Invasividade Neoplásica , Transdução de Sinais , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Variações do Número de Cópias de DNA , Regulação para Baixo , Feminino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Pessoa de Meia-Idade , Prognóstico , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Estudos Retrospectivos , Regulação para Cima
10.
Cancers (Basel) ; 13(3)2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33494434

RESUMO

Radiotherapy (RT) is a key component of cancer treatment. Most of the time, radiation is given after surgery but for soft-tissue sarcomas (STS), pre-surgical radiation is commonly utilized. However, despite improvements in RT accuracy, the rate of local recurrence remains high and is the major cause of death for patients with STS. A better understanding of cell fates in response to RT could provide new therapeutic options to enhance tumour cell killing by RT and facilitate surgical resection. Here, we showed that irradiated STS cell cultures do not die but instead undergo therapy-induced senescence (TIS), which is characterized by proliferation arrest, senescence-associated ß-galactosidase activity, secretion of inflammatory cytokines and persistent DNA damage. STS-TIS was also associated with increased levels of the anti-apoptotic Bcl-2 family of proteins which rendered cells targetable using senolytic Bcl-2 inhibitors. As oppose to radiation alone, the addition of senolytic agents Venetoclax (ABT-199) or Navitoclax (ABT-263) after irradiation induced a rapid apoptotic cell death in STS monolayer cultures and in a more complex three-dimensional culture model. Together, these data suggest a new promising therapeutic approach for sarcoma patients who receive neoadjuvant RT. The addition of senolytic agents to radiation treatments may significantly reduce tumour volume prior to surgery and thereby improve the clinical outcome of patients.

11.
Adv Cancer Res ; 150: 335-363, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33858600

RESUMO

Cellular senescence, cancer and aging are highly interconnected. Among many important molecular machines that lie at the intersection of this triad, the mechanistic (formerly mammalian) target of rapamycin (mTOR) is a central regulator of cell metabolism, proliferation, and survival. The mTOR signaling cascade is essential to maintain cellular homeostasis in normal biological processes or in response to stress, and its dysregulation is implicated in the progression of many disorders, including age-associated diseases. Accordingly, the pharmacological implications of mTOR inhibition using rapamycin or others rapalogs span the treatment of various human diseases from immune disorders to cancer. Importantly, rapamycin is one of the only known pan-species drugs that can extend lifespan. The molecular and cellular mechanisms explaining the phenotypic consequences of mTOR are vast and heavily studied. In this review, we will focus on the potential role of mTOR in the context of cellular senescence, a tumor suppressor mechanism and a pillar of aging. We will explore the link between senescence, autophagy and mTOR and discuss the opportunities to exploit senescence-associated mTOR functions to manipulate senescence phenotypes in age-associated diseases and cancer treatment.


Assuntos
Senescência Celular/genética , Terapia de Alvo Molecular/métodos , Serina-Treonina Quinases TOR/fisiologia , Envelhecimento/fisiologia , Animais , Antineoplásicos/uso terapêutico , Autofagia/fisiologia , Humanos , Terapia de Alvo Molecular/tendências , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Neoplasias/terapia , Inibidores de Proteínas Quinases/uso terapêutico
12.
Nutrients ; 13(3)2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33802038

RESUMO

Many studies have highlighted the relationship between food and health status, with the aim of improving both disease prevention and life expectancy. Among the different food groups, fermented foods a have huge microbial biodiversity, making them an interesting source of metabolites that could exhibit health benefits. Our previous study highlighted the capacity of raw goat milk cheese, and some of the extracts recovered by the means of chemical fractionation, to increase the longevity of the nematode Caenorhabditis elegans. In this article, we pursued the investigation with a view toward understanding the biological mechanisms involved in this phenomenon. Using mutant nematode strains, we evaluated the implication of the insulin-like DAF-2/DAF-16 and the p38 MAPK pathways in the phenomenon of increased longevity and oxidative-stress resistance mechanisms. Our results demonstrated that freeze-dried raw goat milk cheese, and its extracts, induced the activation of the DAF-2/DAF-16 pathway, increasing longevity. Concerning oxidative-stress resistance, all the extracts increased the survival of the worms, but no evidence of the implication of both of the pathways was highlighted, except for the cheese-lipid extract that did seem to require both pathways to improve the survival rate. Simultaneously, the cheese-lipid extract and the dried extract W70, obtained with water, were able to reduce the reactive oxygen species (ROS) production in human leukocytes. This result is in good correlation with the results obtained with the nematode.


Assuntos
Caenorhabditis elegans/fisiologia , Queijo , Leucócitos/fisiologia , Estresse Oxidativo , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Núcleo Celular/metabolismo , Sobrevivência Celular , Alimentos em Conserva , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Liofilização , Regulação da Expressão Gênica , Longevidade , MAP Quinase Quinase 4/genética , MAP Quinase Quinase 4/metabolismo , Sistema de Sinalização das MAP Quinases , Leite , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mutação , Oxirredução , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Acetato de Tetradecanoilforbol/farmacologia
13.
Transplant Cell Ther ; 27(1): 76.e1-76.e9, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33022376

RESUMO

Rapid T cell reconstitution following hematopoietic stem cell transplantation (HSCT) is essential for protection against infections and has been associated with lower incidence of chronic graft-versus-host disease (cGVHD), relapse, and transplant-related mortality (TRM). While cord blood (CB) transplants are associated with lower rates of cGVHD and relapse, their low stem cell content results in slower immune reconstitution and higher risk of graft failure, severe infections, and TRM. Recently, results of a phase I/II trial revealed that single UM171-expanded CB transplant allowed the use of smaller CB units without compromising engraftment (www.clinicaltrials.gov, NCT02668315). We assessed T cell reconstitution in patients who underwent transplantation with UM171-expanded CB grafts and retrospectively compared it to that of patients receiving unmanipulated CB transplants. While median T cell dose infused was at least 2 to 3 times lower than that of unmanipulated CB, numbers and phenotype of T cells at 3, 6, and 12 months post-transplant were similar between the 2 cohorts. T cell receptor sequencing analyses revealed that UM171 patients had greater T cell diversity and higher numbers of clonotypes at 12 months post-transplant. This was associated with higher counts of naive T cells and recent thymic emigrants, suggesting active thymopoiesis and correlating with the demonstration that UM171 expands common lymphoid progenitors in vitro. UM171 patients also showed rapid virus-specific T cell reactivity and significantly reduced incidence of severe infections. These results suggest that UM171 patients benefit from rapid T cell reconstitution, which likely contributes to the absence of moderate/severe cGVHD, infection-related mortality, and late TRM observed in this cohort.


Assuntos
Transplante de Células-Tronco de Sangue do Cordão Umbilical , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco de Sangue do Cordão Umbilical/efeitos adversos , Sangue Fetal , Humanos , Estudos Retrospectivos , Linfócitos T
14.
Cancers (Basel) ; 12(9)2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32825725

RESUMO

Genomic analyses of head and neck squamous cell carcinoma (HNSCC) have highlighted alterations in the phosphatidylinositol 3-kinase (PI3K) signaling pathway, presenting a therapeutic target for multiple ongoing clinical trials with PI3K or PI3K/MTOR inhibitors. However, these inhibitors can potentially increase autophagy in HNSCC and indirectly support cancer cell survival. Here, we sought to understand the relationship between the PI3K signaling pathway and autophagy during their dual inhibition in a panel of HNSCC cell lines. We used acridine orange staining, immunoblotting, and tandem sensor Red Fluorescent Protein- Green Fluorescent Protein-, microtubule-associated protein 1 light chain 3 beta (RFP-GFP-LC3B) expression analysis to show that PI3K inhibitors increase autophagosomes in HNSCC cells, but that chloroquine treatment effectively inhibits the autophagy that is induced by PI3K inhibitors. Using the Bliss independence model, we determined that the combination of chloroquine with PI3K inhibitors works in synergy to decrease cancer cell proliferation, independent of the PIK3CA status of the cell line. Our results indicate that a strategy focusing on autophagy inhibition enhances the efficacy of therapeutics already in clinical trials. Our results suggest a broader application for this combination therapy that can be promptly translated to in vivo studies.

15.
PLoS One ; 15(11): e0242370, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33211771

RESUMO

With the ever-increasing human lifespan, age-related affections have become a public health issue. The health sector is looking for new bioactive compounds to respond to this demand. The unexplored microbial biodiversity and its metabolites represent a major source of innovative bioactive molecules with health potential. Fermented foods, such as raw-milk cheese, have already been investigated for their rich microbial environment, especially for their organoleptic qualities. But studies remain limited regarding their effects on health and few metabolites of microbial origin have been identified. An efficient methodology was developed in this study to investigate the biological effect of raw-milk cheese, combining a chemical fractionation, to isolate the most metabolites from the cheese matrix, and an in vivo biological test using Caenorhabditis elegans. C. elegans was brought into contact with cheese extracts, obtained by means of chemical fractionation, and with freeze-dried whole cheese by supplementing the nematode growth medium. A longevity assay was performed to evaluate the effects of the extracts on the worms. Our results demonstrate the feasibility of the method developed to bring the worms into contact of the cheese extracts. The evaluation of the effects of the extracts on the longevity was possible. Some extracts showed a beneficial effect as extract W70 for example, obtained with water, which increases the mean lifespan by 16% and extends the longevity by 73% (p < 0.0001).


Assuntos
Caenorhabditis elegans/efeitos dos fármacos , Queijo/análise , Fracionamento Químico/métodos , Misturas Complexas/farmacologia , Análise de Alimentos/métodos , Acetatos , Animais , Caenorhabditis elegans/fisiologia , Misturas Complexas/isolamento & purificação , Misturas Complexas/toxicidade , Cicloexanos , Etanol , Estudos de Viabilidade , Liofilização , Cabras , Interações Hidrofóbicas e Hidrofílicas , Longevidade/efeitos dos fármacos , Cloreto de Metileno , Leite/química , Solventes , Água
16.
Autophagy ; 16(11): 2004-2016, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-31931659

RESUMO

Sustained macroautophagy/autophagy favors the differentiation of fibroblasts into myofibroblasts. Cellular senescence, another means of responding to long-term cellular stress, has also been linked to myofibroblast differentiation and fibrosis. Here, we evaluate the relationship between senescence and myofibroblast differentiation in the context of sustained autophagy. We analyzed markers of cell cycle arrest/senescence in fibroblasts in vitro, where autophagy was triggered by serum starvation (SS). Autophagic fibroblasts expressed the senescence biomarkers CDKN1A/p21 and CDKN2A/p16 and exhibited increased senescence-associated GLB1/beta-galactosidase activity. Inhibition of autophagy in serum-starved fibroblasts with 3-methyladenine, LY294002, or ATG7 (autophagy related 7) silencing prevented the expression of senescence-associated markers. Similarly, suppressing MTORC2 activation using rapamycin or by silencing RICTOR also prevented senescence hallmarks. Immunofluorescence microscopy showed that senescence and myofibroblast differentiation were induced in different cells, suggesting mutually exclusive activation of senescence and myofibroblast differentiation. Reactive oxygen species (ROS) are known inducers of senescence and exposing fibroblasts to ROS scavengers decreased ROS production during SS, inhibited autophagy, and significantly reduced the expression of senescence and myofibroblast differentiation markers. ROS scavengers also curbed the AKT1 phosphorylation at Ser473, an MTORC2 target, establishing the importance of ROS in fueling MTORC2 activation. Inhibition of senescence by shRNA to TP53/p53 and shRNA CDKN2A/p16 increased myofibroblast differentiation, suggesting a negative feedback loop of senescence on autophagy-induced myofibroblast differentiation. Collectively, our results identify ROS as central inducers of MTORC2 activation during chronic autophagy, which in turn fuels senescence activation and myofibroblast differentiation in distinct cellular subpopulations. Abbreviations: 3-MA: 3-methyladenine; ACTA2: actin, alpha 2, smooth muscle, aorta; AKT1: AKT serine/threonine kinase 1; p-AKT1: AKT1 Ser473 phosphorylation; t-AKT1: total AKT serine/threonine kinase 1; ATG4A: autophagy related 4A cysteine peptidase; ATG7: autophagy gene 7; C12FDG: 5-dodecanoylaminofluorescein Di-ß-D-Galactopyranoside; CDKN1A: cyclin dependent kinase inhibitor 1A; CDKN2A: cyclin dependent kinase inhibitor 2A; Ctl: control; DAPI: 4',6-diamidino-2-phenylindole, dilactate; ECM: extracellular matrix; GSH: L-glutathione reduced; H2O2: hydrogen peroxide; HLF: adult human lung fibroblasts; Ho: Hoechst 33342 (2'-[4-ethoxyphenyl]-5-[4-methyl-1-piperazinyl]-2.5'-bi-1H-benzimidazole); HSC: hepatic stellate cells; LY: LY294002; MAP1LC3B/LC3B: microtubule-associated protein 1 light chain 3 beta; MTORC1/2: mechanistic target of rapamycin kinase complex 1/2; N: normal growth medium; NAC: N-acetyl-L-cysteine; PBS: phosphate-buffered saline; PDGFA: platelet derived growth factor subunit A; PRKCA/PKCα: protein kinase C alpha; PtdIns3K: class III phosphatidylinositol 3-kinase; PTEN: phosphatase and tensin homolog; R: rapamycin; RICTOR: RPTOR independent companion of MTOR complex 2; ROS: reactive oxygen species; RPTOR: regulatory associated protein of MTOR complex 1; SA-GLB1/ß-gal: senescence-associated galactosidase beta 1; SGK1: serum/glucocorticoid regulated kinase 1; shRNA: short hairpin RNA; siCtl: control siRNA; siRNA: small interfering RNA; SQSTM1: sequestosome 1; SS: serum-free (serum starvation) medium; TP53: tumor protein p53; TUBA: tubulin alpha; V: vehicle.


Assuntos
Autofagia/fisiologia , Fibroblastos/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Humanos , Proteína Sequestossoma-1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Sirolimo/farmacologia
17.
Sci Rep ; 10(1): 21507, 2020 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-33299020

RESUMO

Survivors of childhood acute lymphoblastic leukemia (cALL) are at higher risk of developing cardiometabolic complications. We aimed at exploring the associations between biomarkers of inflammation, oxidative stress, endothelial function, endotoxemia and cardiometabolic risk factors. We conducted a cross-sectional analysis in 246 cALL survivors (mean age, 22.1 ± 6.3 years; mean time since diagnosis, 15.5 ± 5.2 years) and evaluated the associations using a series of logistic regressions. Using structural equation models, we also tested if the relationship between endotoxemia and cardiometabolic complications was mediated by the latent (unobserved) variable inflammation inferred from the observed biomarkers CRP, TNF-α and IL-6. High leptin-adiponectin ratio was associated with obesity [adjusted OR = 15.7; 95% CI (6.2-39.7)], insulin resistance [20.6 (5.2-82.1)] and the metabolic syndrome [11.2 (2.6-48.7)]. Higher levels of plasminogen activator inhibitor-1 and tumor necrosis factor-α were associated with obesity [3.37 (1.6-7.1) and 2.34 (1.3-4.2), respectively] whereas high C-reactive protein levels were associated with insulin resistance [3.3 (1.6-6.8)], dyslipidemia [2.6 (1.4-4.9)] and MetS [6.5 (2.4-17.9)]. Our analyses provided evidence for a directional relationship between lipopolysaccharide binding protein, related to metabolic endotoxemia, inflammation and cardiometabolic outcomes. Identification of biomarkers and biological mechanisms could open new avenues for prevention strategies to minimize the long-term sequelae, improve follow-up and optimize the quality of life of this high-risk population.


Assuntos
Biomarcadores/sangue , Doenças Cardiovasculares/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Adiponectina , Adolescente , Adulto , Sobreviventes de Câncer/estatística & dados numéricos , Estudos Transversais , Dislipidemias/complicações , Feminino , Humanos , Inflamação/complicações , Leptina , Masculino , Síndrome Metabólica/metabolismo , Obesidade/complicações , Estresse Oxidativo/fisiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Qualidade de Vida , Fatores de Risco , Adulto Jovem
18.
Biometals ; 22(5): 753-69, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19294337

RESUMO

Cadmium (Cd) is a highly toxic metal that enters the food chain. Following oral ingestion, the intestinal epithelium is the first biological barrier crossed by Cd and is also an important target tissue. In the present study, the human intestinal Caco-2 cell line was used to evaluate the impact of a low level of exposure on both undifferentiated and differentiated intestinal cells. As revealed by the LC(50) values estimated with the 3-[4,5-dimethyl-2-thiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay, mature Caco-2 cells were more resistant to Cd. However, following a 24-h exposure to non-cytotoxic levels of Cd (10 microM) or zinc (Zn, 100 microM), threefold increases were obtained in the LC(50) values of 7-day-old cells, whereas increased resistance in 21-day-old cells was observed exclusively with Zn. Induction of MT-IIa and HSP70 mRNAs was higher in undifferentiated cells and an increase in cellular glutathione (GSH) content was observed exclusively in these cell cultures. However, the results obtained with cycloheximide used for inhibiting protein synthesis and with L-buthionine sulfoximine (BSO), which inhibits GSH synthesis, revealed that protein synthesis is not a prerequisite to the development of resistance. The presence of 100 mM 3-amino-1,2,4-triazole (3AT), a catalase inhibitor, prevented Cd-induced but not Zn-induced resistance, as well as sensitized cells to Cd toxicity. These results show for the first time differences in constitutive and acquired resistance to Cd as a function of enterocytic differentiation status and suggest the involvement of different mechanisms for Cd- and Zn-induced adaptation in the intestinal cells. Redox signals may trigger Cd-induced adaptation mechanisms but pro-oxidant conditions would eliminate proliferative intestinal cells capability to develop resistance. This would be critical for Cd- but not Zn-induced mechanisms of resistance since Cd but not Zn may cause oxidative stress.


Assuntos
Células CACO-2/efeitos dos fármacos , Cádmio/toxicidade , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Zinco/toxicidade , Células CACO-2/citologia , Células CACO-2/metabolismo , Catalase/antagonistas & inibidores , Glutationa/metabolismo , Proteínas de Choque Térmico HSP72/genética , Humanos , Transdução de Sinais/efeitos dos fármacos , Triazóis/farmacologia
19.
Cancers (Basel) ; 12(1)2019 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-31878157

RESUMO

Genetic factors behind the increasing incidence of human papillomavirus (HPV) negative head and neck squamous cell carcinoma (HNSCC) in young non-smokers are suspected, but have not been identified. Recently, rs6942067, a single nucleotide polymorphism (SNP) located upstream of the DCBLD1 gene, was found associated with non-smoking lung adenocarcinoma. To validate if this SNP is also implicated in HNSCC, participants of The Cancer Genome Atlas HNSCC cohort were investigated for rs6942067 status, associated DCBLD1 expression, and clinical characteristics. Occurrence of the rs6942067 GG genotype is significantly higher in young and in HPV negative non-smoking HNSCC than in other HNSCC. Additionally, rs6942067 GG is associated with higher DCBLD1 expression in HNSCC and patients with high DCBLD1 expression have a worse overall survival at three years, both in univariate and multivariate analysis. Furthermore, high DCBLD1 expression is associated with activation of the integrin signaling pathway and its phosphorylation with EGFR and MET. Collectively, these findings suggest that DCBLD1 plays a critical role in HNSCC and demonstrate an association between rs6942067 and clinical characteristics of young age and HPV negative non-smoking status in HNSCC patients.

20.
Oncotarget ; 9(31): 21641-21654, 2018 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-29774091

RESUMO

Metastatic nodal involvement is a critical prognostic factor in uterine cervical cancer (UCC). To improve current methods of detecting UCC metastases in lymph nodes (LNs), we used quantitative PCR (qPCR) to assess mRNA expression of potential metastatic biomarkers. We found that expression of HPV16-E6, cytokeratin19 (CK19), and mucin1 (MUC1) is consistently upregulated in tumors and metastatic tissues, supporting a role for these genes in UCC progression. These putative biomarkers were able to predict the presence of histologically positive metastatic LNs with respective sensitivities and specificities of 82% and 99% (CK19), 76% and 95% (HPV16-E6), and 76% and 78% (MUC1). While the biomarkers failed to detect 1.7% to 2.2% of the histologically positive LNs when used individually, combining CK19 and HPV16-E6 enhanced sensitivity and specificity to 100% and 94%, respectively. To explore the sensitivity of qPCR-based detection of varying proportions of invading HPV16-positive UCC cells, we designed a LN metastasis model that achieved a fresh cell detection limit of 0.008% (1:12500 HPV16-positive to HPV16-negative cells), and a paraffin-embedded, formalin-fixed (PEFF) detection limit of 0.02% (1:5000 HPV16-positive to HPV16-negative cells), both of which are within the theoretical detection limit for micrometastasis. Thus, HPV E6/E7 oncogenes may be useful targets for the ultrasensitive detection of nodal involvements like micrometastases in fresh or archived tissue samples. Moreover, our results suggest that the biomarker combination of CK19/HPV-E6 could support a real-time intraoperative strategy for the detection of small, but potentially lethal, metastatic nodal involvements in fresh UCC tissues.

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