RESUMO

Telomere length (TL) is increasingly recognized as a molecular marker that reflects how reproductive aging affects intergenerational transmissions. Here, we investigated the effects of parental age on offspring survival and the regulation of TL by examining the telomere-elongating activity of telomerase in the Pacific oyster. We assessed the classical hallmarks of aging in parents at three age classes (young, middle-aged, and old) and crossbred them using a split-brood design to examine the consequences of the nine maternal-by-paternal age combinations on their offspring. Reproductive aging leads to increased larval mortality and accelerated telomere shortening in spats, rendering them more susceptible to infection by the Ostreid herpesvirus. Viral exposure stimulates telomerase activity, a response that we identified as adaptive, but weakened by parental aging. While telomerase lengthens a spat's telomere, paradoxically, longer individual TL predicts higher mortality in adults. The telomerase-telomere complex appeared as a conservative biomarker for distinguishing survivors and losers upon exposure to polymicrobial diseases.

Assuntos

Envelhecimento , Reprodução , Telomerase , Animais , Telomerase/metabolismo , Telomerase/genética , Telômero/metabolismo , Telômero/genética , Herpesviridae/fisiologia , Feminino , Homeostase do Telômero , Ostreidae/virologia

RESUMO

Sarcoma is a rare tumor derived from the mesenchymal tissue and mainly found in children and adolescents. The outcome for patients with sarcoma is relatively poor compared with that for many other solid malignant tumors. Sarcomas have a highly heterogeneous pathogenesis, histopathology and biological behavior. Dysregulated signaling pathways and various gene mutations are frequently observed in sarcomas. The telomere maintenance mechanism (TMM) has recently been considered as a prognostic factor for patients with sarcomas, and alternative lengthening of telomeres (ALT) positivity has been correlated with poor outcomes in patients with several types of sarcomas. Therefore, telomeres and telomerases may be useful targets for treating sarcomas. This review aims to provide an overview of telomere and telomerase biology in sarcomas.

Assuntos

Sarcoma , Telomerase , Homeostase do Telômero , Telômero , Humanos , Telomerase/genética , Telomerase/metabolismo , Sarcoma/genética , Sarcoma/terapia , Sarcoma/patologia , Telômero/genética , Telômero/metabolismo , Homeostase do Telômero/genética , Prognóstico , Mutação

RESUMO

An increasing body of evidence suggests that acylphosphatase-2 (ACYP2) polymorphisms are correlated with an increased susceptibility to a range of malignancies. Nevertheless, its potential functions, molecular mechanisms in hepatocellular carcinoma (HCC) and whether it can be act as a therapeutic target remain uninvestigated. Herein, ACYP2 was found to be lowly expressed in HCC and was negatively correlated with tumor size, tumor differentiation, microvascular invasion and the prognosis of HCC patients. Functional investigations revealed that overexpression of ACYP2 inhibited the proliferation and metastasis of HCC cells while promoting apoptosis; knockdown of ACYP2 had the exact opposite effect. Additionally, it was observed that ACYP2 was distributed in both the cytoplasm and nucleus of HCC cells. According to the mechanistic studies, the expression of potassium calcium-activated channel subfamily N member 4 (KCNN4) was negatively regulated by cytoplasmic ACYP2, resulting in the inhibition of K+ outflow and subsequent inactivation of the ERK pathway, which impeded the growth and metastasis of HCC. Furthermore, the activity of telomerase reverse transcriptase (TERT) was inhibited by nuclear ACYP2, leading to the reduction in length of telomeres and consequent reversal of HCC cell immortalization. Additionally, a novel targeted nanotherapy strategy was developed wherein the pcDNA-ACYP2 vector was encapsulated within polyetherimide nanoparticles (PEI/NPs), which were subsequently coated with HCC cell membranes (namely pcDNA/PEI/NPs@M). Safety and targeting characteristics abound for these nanocomposites, in both subcutaneous graft tumor models and orthotopic mouse models, they inhibited the progression of HCC by impeding TERT activity and the KCNN4/ERK pathway. In conclusion, our research identifies novel molecular mechanisms involving cytoplasmic and nuclear ACYP2 that inhibit the progression of HCC. Moreover, pcDNA/PEI/NPs@M represents a targeted therapeutic strategy for HCC that holds great promising.

Assuntos

Carcinoma Hepatocelular , Proliferação de Células , Canais de Potássio Ativados por Cálcio de Condutância Intermediária , Neoplasias Hepáticas , Sistema de Sinalização das MAP Quinases , Telomerase , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Telomerase/metabolismo , Telomerase/genética , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Camundongos , Masculino , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/metabolismo , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/antagonistas & inibidores , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/genética , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos Nus , Apoptose/efeitos dos fármacos , Feminino , Progressão da Doença , Camundongos Endogâmicos BALB C , Nanopartículas/química , Pessoa de Meia-Idade

RESUMO

Telomeres are ribonucleoprotein structures that form a protective buffer at the ends of chromosomes, maintaining genomic integrity during the cell cycle. A decrease in average telomere length is associated with with age and with aging-related diseases such as cancer and cardiovascular disease. In this study, we conducted a randomized, double-blind, placebo-controlled trial over six months to compare the effects of the Astragalus-based supplement versus a placebo on telomere length (TL) in 40 healthy volunteers (mean age 56.1 ± 6.0 years). Twenty subjects received the supplement, and 20 received placebo capsules. All participants completed the study, and no adverse side effects were reported at six months. Subjects taking the Astragalus-based supplement exhibited significantly longer median TL (p = 0.01) and short TL (p = 0.004), along with a lower percentage of short telomeres, over the six-month period, while the placebo group showed no change in TL. This trial confirmed that the supplement significantly lengthens both median and short telomeres by increasing telomerase activity and reducing the percentage of short telomeres (<3 Kbp) in a statistically and possibly clinically significant manner. These results align with a previous open prospective trial, which found no toxicity associated with the supplement's intake. These findings suggest that this Astragalus-based supplement warrants further investigation for its potential benefits in promoting health, extending life expectancy, and supporting healthy aging.

Assuntos

Astrágalo , Suplementos Nutricionais , Telomerase , Telômero , Humanos , Método Duplo-Cego , Pessoa de Meia-Idade , Masculino , Feminino , Astrágalo/química , Telômero/efeitos dos fármacos , Telomerase/metabolismo , Homeostase do Telômero/efeitos dos fármacos , Encurtamento do Telômero/efeitos dos fármacos

RESUMO

Telomere dysfunction is a well-known molecular trigger of senescence and has been associated with various age-related diseases, including atherosclerosis. However, the mechanisms involved have not yet been elucidated, and the extent to which telomeres contribute to atherosclerosis is unknown. Therefore, we investigated the mechanism of metformin-induced telomere stabilization and the ability of metformin to inhibit vascular smooth muscle cell (VSMC) senescence caused by advanced atherosclerosis. The present study revealed that metformin inhibited the phenotypes of atherosclerosis and senescence in VSMCs. Metformin increased the phosphorylation of AMPK-dependent PGC-1α and thus increased telomerase activity and the protein level of TERT in OA-treated VSMCs. Mechanistically, the phosphorylation of AMPK and PGC-1α by metformin not only enhanced telomere function but also increased the protein level of TERT, whereas TERT knockdown accelerated the development of atherosclerosis and senescent phenotypes in OA-treated VSMCs regardless of metformin treatment. Furthermore, the in vivo results showed that metformin attenuated the formation of atherosclerotic plaque markers in the aortas of HFD-fed ApoE KO mice. Although metformin did not reduce plaque size, it inhibited the phosphorylation of the AMPK/PGC-1α/TERT signaling cascade, which is associated with the maintenance and progression of plaque formation, in HFD-fed ApoE KO mice. Accordingly, metformin inhibited atherosclerosis-associated phenotypes in vitro and in vivo. These observations show that the enhancement of telomere function by metformin is involved in specific signaling pathways during the progression of atherosclerosis. These findings suggest that telomere stabilization by metformin via the AMPK/p-PGC-1α pathway might provide a strategy for developing therapeutics against vascular diseases such as atherosclerosis.

Assuntos

Proteínas Quinases Ativadas por AMP , Aterosclerose , Metformina , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Transdução de Sinais , Telômero , Metformina/farmacologia , Metformina/uso terapêutico , Animais , Aterosclerose/metabolismo , Aterosclerose/tratamento farmacológico , Aterosclerose/patologia , Aterosclerose/etiologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Camundongos , Proteínas Quinases Ativadas por AMP/metabolismo , Transdução de Sinais/efeitos dos fármacos , Telômero/metabolismo , Telômero/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Músculo Liso Vascular/efeitos dos fármacos , Masculino , Telomerase/metabolismo , Telomerase/genética , Fosforilação/efeitos dos fármacos , Progressão da Doença , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/efeitos dos fármacos , Camundongos Knockout , Homeostase do Telômero/efeitos dos fármacos , Modelos Animais de Doenças

RESUMO

Premature telomere shortening or telomere instability is associated with a group of rare and heterogeneous diseases collectively known as telomere biology disorders (TBDs). Here we identified two unrelated individuals with clinical manifestations of TBDs and short telomeres associated with the identical monoallelic variant c.767A>G; Y256C in RPA2 Although the replication protein A2 (RPA2) mutant did not affect ssDNA binding and G-quadruplex-unfolding properties of RPA, the mutation reduced the affinity of RPA2 with the ubiquitin ligase RFWD3 and reduced RPA ubiquitination. Using engineered knock-in cell lines, we found an accumulation of RPA at telomeres that did not trigger ATR activation but caused short and dysfunctional telomeres. Finally, both patients acquired, in a subset of blood cells, somatic genetic rescue events in either POT1 genes or TERT promoters known to counteract the accelerated telomere shortening. Collectively, our study indicates that variants in RPA2 represent a novel genetic cause of TBDs. Our results further support the fundamental role of the RPA complex in regulating telomere length and stability in humans.

Assuntos

Proteína de Replicação A , Proteínas de Ligação a Telômeros , Telômero , Humanos , Proteína de Replicação A/genética , Proteína de Replicação A/metabolismo , Telômero/genética , Proteínas de Ligação a Telômeros/genética , Proteínas de Ligação a Telômeros/metabolismo , Heterozigoto , Masculino , Feminino , Complexo Shelterina , Encurtamento do Telômero/genética , Mutação , Telomerase/genética , Telomerase/metabolismo , Ubiquitinação/genética , Ubiquitina-Proteína Ligases/genética

RESUMO

BACKGROUND: Fasting potentially alters the aging process induced by obesity by regulating telomere integrity, which is related to longevity genes. However, the impact of periodic fasting (PF) on the expression of longevity genes, particularly Forkhead Box O Transcription Factors (FOXO3a) and the Human Telomerase Reverse Transcriptase (hTERT), is not fully understood. This study aimed to analyze the effects of PF, specifically on FOXO3a, hTERT expression, and other associated factors. METHODS: A quasi-experimental 10-day study was conducted in Surabaya, East Java, Indonesia. This study consisted of an intervention group (PFG), which carried out PF for ten days using a daily 12 h time-restricted eating protocol, and a control group (CG), which had daily meals as usual. FOXO3a and hTERT expression were analyzed by quantitative real-time qPCR. A paired t-test/Wilcoxon test, independent t-test/Mann-Whitney U-test, and Spearman's correlation test were used for statistical analysis. RESULT: Thirty-six young men participated in this study. During the post-test period, FOXO3a expression in the PFG increased 28.56 (±114.05) times compared to the pre-test, but the difference was not significant. hTERT expression was significantly higher in both the CG and PFG. The hTERT expression in the PFG was 10.26 (±8.46) times higher than in the CG, which was only 4.73 (±4.81) times higher. There was also a positive relationship between FOXO and hTERT in the CG. CONCLUSIONS: PF significantly increased hTERT expression in the PFG; however, no significant increase was found in FOXO3a expression. PF regimens using the 12 h time-restricted eating approach may become a potential strategy for preventing obesity-induced premature aging by regulating longevity gene expression.

Assuntos

Jejum , Proteína Forkhead Box O3 , Longevidade , Obesidade , Sobrepeso , Telomerase , Humanos , Masculino , Proteína Forkhead Box O3/genética , Proteína Forkhead Box O3/metabolismo , Longevidade/genética , Obesidade/genética , Telomerase/genética , Telomerase/metabolismo , Sobrepeso/genética , Adulto , Adulto Jovem , Indonésia , Regulação da Expressão Gênica

RESUMO

Multiple myeloma is a hematological cancer caused by the uncontrolled proliferation of abnormal plasma cells in the bone marrow, leading to excessive immunoglobulin production. Our study aimed to examine the anticancer properties of BRF1A, a cannabinoid (CBD)-enriched product, on 2 myeloma cell lines: U266 and ARH-7. We treated U266 and ARH-77 myeloma cells with varying doses of BRF1A and measured the production of IgE and IgG antibodies using ELISA. Cell viability was assessed using trypan blue and CCK-8 assays. We measured the expression of genes related to the production of IgE and IgG antibodies, IgEH, and IgGH. We determined its effect on the expression of telomerase and its phosphorylated form as an indicator of telomere stabilization. Furthermore, we determined its effect on other cancer-related targets such as NF-ĸB, c-Myc, and TP53 in U266 cells using reverse transcription polymerase chain reaction (RT-PCR) and western blotting. BRF1A reduced myeloma cell IgE and IgG production in a time and dose-dependent manner. It also suppressed the expression of p-IκBα, p-NFκB (p65), and total NFκB protein, as well as XBP1u and XBP1s. It increased the gene and protein expression of telomere and hTERT and significantly increased cancer suppressor TP53 gene and p53 protein expression. Additionally, BRF1A decreased the c-Myc gene and protein expression. Our study has shown that a CBD-enriched product can reduce the growth of myeloma cells by suppressing the critical functions of IgE- and IgG-producing cells. This study could help bridge the gap in understanding how cannabinoid-containing products affect cancer, aging, telomere, and cancer-suppressor gene activity.

Assuntos

Canabinoides , Mieloma Múltiplo , Telomerase , Telômero , Proteína Supressora de Tumor p53 , Humanos , Mieloma Múltiplo/tratamento farmacológico , Linhagem Celular Tumoral , Telômero/efeitos dos fármacos , Telômero/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Canabinoides/farmacologia , Telomerase/metabolismo , Sobrevivência Celular/efeitos dos fármacos , NF-kappa B/metabolismo , Imunoglobulina E , Imunoglobulina G , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos

RESUMO

There are few convincing studies establishing the relationship between endogenous factors that cause obesity, cellular aging, and telomere shortening. Without a functional telomerase, a cell undergoing cell division has progressive telomere shortening. While obesity influences health and longevity as well as telomere dynamics, cellular senescence is one of the major drivers of the aging process and of age-related disorders. Oxidative stress induces telomere shortening, while decreasing telomerase activity. When progressive shortening of telomere length reaches a critical point, it triggers cell cycle arrest leading to senescence or apoptotic cell death. Telomerase activity cannot be detected in normal breast tissue. By contrast, maintenance of telomere length as a function of human telomerase is crucial for the survival of breast cancer cells and invasion. Approximately three-quarters of breast cancers in the general population are hormone-dependent and overexpression of estrogen receptors is crucial for their continued growth. In obesity, increasing leptin levels enhance aromatase messenger ribonucleic acid (mRNA) expression, aromatase content, and its enzymatic activity on breast cancer cells, simultaneously activating telomerase in a dose-dependent manner. Meanwhile, applied anti-estrogen therapy increases serum leptin levels and thus enhances leptin resistance in obese postmenopausal breast cancer patients. Many studies revealed that shorter telomeres of postmenopausal breast cancer have higher local recurrence rates and higher tumor grade. In this review, interlinked molecular mechanisms are looked over between the telomere length, lipotoxicity/glycolipotoxicity, and cellular senescence in the context of estrogen receptor alpha-positive (ERα+) postmenopausal breast cancers in obese women. Furthermore, the effect of the potential drugs, which are used for direct inhibition of telomerase and the inhibition of human telomerase reverse transcriptase (hTERT) or human telomerase RNA promoters as well as approved adjuvant endocrine therapies, the selective estrogen receptor modulator and selective estrogen receptor down-regulators are discussed.

Assuntos

Neoplasias da Mama , Senescência Celular , Obesidade , Telomerase , Humanos , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Feminino , Obesidade/genética , Obesidade/metabolismo , Telomerase/metabolismo , Telomerase/genética , Encurtamento do Telômero , Telômero/metabolismo , Telômero/genética , Leptina/metabolismo , Leptina/genética , Animais

RESUMO

Living with chronic pain is associated with substantial suffering and high societal costs. Patient reported outcomes (PROM's) and cellular ageing should be considered in pain management. The aim of this study was to explore correlations of PROM's and cellular ageing (telomere length [TL] and telomerase activity [TA]) amongst patients with chronic non-malignant pain. This was an explorative pilot study with cross-sectional design and recruitment was done at two pain rehabilitation facilities in Sweden, with inpatient setting/integrative care and outpatient setting/multimodal care, respectively. Eighty-four patients were enrolled by referral to pain rehabilitation in Sweden. The main outcome measures collected after admission in addition to TL and TA were the following PROMs: Numerical Rating Scale (NRS), Chronic Pain Acceptance Questionnaire (CPAQ), Hospital Anxiety and Depression Scale (HADS), Five Facets Mindfulness Questionnaire (FFMQ), WHO Quality of Life-Spiritual, Religious and Personal Beliefs (WHOQoL-SRPB) and EuroQol 5 Dimensions (EQ-5D). All the PROM's showed evidence of poor overall health status among the participants. TL correlated negatively with HADS score (r = -.219, p = .047) and positively with WHOQoL-SRPB (r = .224, p = .052). TL did not correlate with any of the pain measures. TA correlated positively with pain spread (r = .222, p = .049). A mediation of the direct effect of spiritual well-being on TL by anxiety and depression could be shown (b = 0.008; p = .045). The correlations between TL and SRPB and anxiety and depression suggest some importance of emotional and SRPB dimensions in pain management, with implications for cellular aging, which may warrant further study. Trial registration: ClinicalTrials.gov Identifier: NCT02459639.

Assuntos

Dor Crônica , Espiritualidade , Telômero , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor Crônica/psicologia , Estudos Transversais , Depressão/psicologia , Emoções , Medidas de Resultados Relatados pelo Paciente , Projetos Piloto , Qualidade de Vida , Religião , Inquéritos e Questionários , Suécia , Telomerase/metabolismo , Telomerase/genética , Telômero/genética

RESUMO

Prostate cancer (PCa) is the most common cancer diagnosed in men worldwide and was the second leading cause of cancer-related deaths in US males in 2022. Prostate cancer also represents the second highest cancer mortality disparity between non-Hispanic blacks and whites. However, there is a relatively small number of prostate normal and cancer cell lines compared to other cancers. To identify the molecular basis of PCa progression, it is important to have prostate epithelial cell (PrEC) lines as karyotypically normal as possible. Our lab recently developed a novel methodology for the rapid and efficient immortalization of normal human PrEC that combines simultaneous CRISPR-directed inactivation of CDKN2A exon 2 (which directs expression of p16INK4A and p14ARF) and ectopic expression of an hTERT transgene. To optimize this methodology to generate immortalized lines with minimal genetic alterations, we sought to target exon 1α of the CDKN2A locus so that p16INK4A expression is ablated while the exons encoding p14ARF remains unaltered. Here we describe the establishment of two cell lines: one with the above-mentioned p16INK4A only loss, and a second line targeting both products in the CDKN2A locus. We characterize the potential lineage origin of these new cell lines along with our previously obtained clones, revealing distinct gene expression signatures. Based on the analyses of protein markers and RNA expression signatures, these cell lines are most closely related to a subpopulation of basal prostatic cells. Given the simplicity of this one-step methodology and the fact that it uses only the minimal genetic alterations necessary for immortalization, it should also be suitable for the establishment of cell lines from primary prostate tumor samples, an urgent need given the limited number of available prostate cancer cell lines.

Assuntos

Inibidor p16 de Quinase Dependente de Ciclina , Células Epiteliais , Próstata , Neoplasias da Próstata , Telomerase , Humanos , Masculino , Telomerase/genética , Telomerase/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Células Epiteliais/metabolismo , Próstata/metabolismo , Próstata/patologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Neoplasias da Próstata/metabolismo , Éxons/genética , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral , Linhagem Celular

RESUMO

The inevitable acquired resistance to osimertinib (AZD9291), an FDA-approved third-generation EGFR tyrosine kinase inhibitor (EGFR-TKI) for the treatment of patients with advanced non-small cell lung cancer (NSCLC) harboring EGFR activating or T790M resistant mutations, limits its long-term clinical benefit. Telomere maintenance via telomerase reactivation is linked to uncontrolled cell growth and is a cancer hallmark and an attractive cancer therapeutic target. Our effort toward understanding the action mechanisms, including resistance mechanisms, of osimertinib has led to the identification of a novel and critical role in maintaining c-Myc-dependent downregulation of hTERT, a catalytic subunit of telomerase, and subsequent inhibition of telomerase/telomere and induction of telomere dysfunction in mediating therapeutic efficacy of osimertinib. Consequently, osimertinib combined with the telomere inhibitor, 6-Thio-dG, which is currently tested in a phase II trial, effectively inhibited the growth of osimertinib-resistant tumors, regressed EGFRm NSCLC patient-derived xenografts, and delayed the emergence of acquired resistance to osimertinib, warranting clinical validation of this strategy to manage osimertinib acquired resistance.

Assuntos

Acrilamidas , Compostos de Anilina , Carcinoma Pulmonar de Células não Pequenas , Resistencia a Medicamentos Antineoplásicos , Receptores ErbB , Neoplasias Pulmonares , Mutação , Telomerase , Telômero , Acrilamidas/farmacologia , Acrilamidas/uso terapêutico , Telomerase/genética , Telomerase/metabolismo , Telomerase/antagonistas & inibidores , Compostos de Anilina/farmacologia , Compostos de Anilina/uso terapêutico , Humanos , Receptores ErbB/genética , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Animais , Telômero/metabolismo , Telômero/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Indóis , Pirimidinas

RESUMO

Extension of the replicative lifespan of primary cells can be achieved by activating human telomerase reverse transcriptase (hTERT) to maintain sufficient telomere lengths. In this work, we utilize CRISPR/dCas9-based epigenetic modifiers (p300 histone acetyltransferase and TET1 DNA demethylase) and transcriptional activators (VPH and VPR) to reactivate the endogenous TERT gene in unstimulated T cells in the peripheral blood mononuclear cells (PBMCs) by rewiring the epigenetic marks of the TERT promoter. Importantly, we have successfully expanded resting T cells and delayed their cellular senescence for at least three months through TERT reactivation, without affecting the expression of a T-cell marker (CD3) or inducing an accelerated cell division rate. We have also demonstrated the effectiveness of these CRISPR tools in HEK293FT and THP-1-derived macrophages. TERT reactivation and replicative senescence delay were achieved without inducing malignancy transformation, as shown in various cellular senescence assays, cell cycle state, proliferation rate, cell viability, and karyotype analyses. Our chromatin immunoprecipitation (ChIP)-qPCR data together with TERT mRNA and protein expression analyses confirmed the specificity of CRISPR-based transcription activators in modulating epigenetic marks of the TERT promoter, and induced telomerase expression. Therefore, the strategy of cell immortalization described here can be potentially adopted and generalized to delay cell death or even immortalize any other cell types.

Assuntos

Sistemas CRISPR-Cas , Senescência Celular , Epigênese Genética , Regiões Promotoras Genéticas , Linfócitos T , Telomerase , Humanos , Telomerase/genética , Telomerase/metabolismo , Sistemas CRISPR-Cas/genética , Senescência Celular/genética , Regiões Promotoras Genéticas/genética , Linfócitos T/metabolismo , Linfócitos T/citologia , Células HEK293 , Proliferação de Células/genética

RESUMO

Imetelstat (RYTELO™), an oligonucleotide telomerase inhibitor, is being developed by Geron Corporation for the treatment of myeloid hematologic malignancies. In June 2024, imetelstat was approved in the USA for use in adult patients with low- to intermediate-1 risk myelodysplastic syndromes (MDS) with transfusion-dependent anemia requiring 4 or more red blood cell units over 8 weeks who have not responded to or have lost response to or are ineligible for erythropoiesis-stimulating agents (ESA). This article summarizes the milestones in the development of imetelstat leading to this first approval for the treatment of adult patients with low- to intermediate-1 risk MDS with transfusion-dependent anemia.

Assuntos

Aprovação de Drogas , Síndromes Mielodisplásicas , Oligonucleotídeos , Telomerase , Humanos , Síndromes Mielodisplásicas/tratamento farmacológico , Oligonucleotídeos/uso terapêutico , Oligonucleotídeos/farmacologia , Oligonucleotídeos/efeitos adversos , Telomerase/antagonistas & inibidores , Telomerase/metabolismo , Anemia/tratamento farmacológico , Estados Unidos , United States Food and Drug Administration

RESUMO

BACKGROUND: Ceranib-2, an acid ceramidase (AC) inhibitor, can inhibit cancer cell proliferation and tumor development. However, poor water solubility and low cellular bioavailability limit its efficacy in cancer treatment. METHODS AND RESULTS: This study aimed to investigate the cell death induced by ceranib-2 and its solid lipid nanoformulation (ceranib-2-SLN) produced by the hot homogenization technique and the synergistic relationship between ceramide and telomerase in vitro and in silico. Furthermore, this study proved the possible mechanism of ceranib-2-induced AC inhibition by in silico studies. The effective cytotoxic concentrations of ceranib-2, telomerase level, and changes in ceramide levels were measured by MTT colorimetric cytotoxicity assay, ELISA, and LC/MS/MS methods, respectively. TEM results showed that ceranib-2-SLN was 13-fold smaller than the size of ceranib-2. Ceranib-2 and ceranib-2-SLN had IC50 concentrations of 31.62 (± 2.1) and 27.69 (± 1.75) µM in A549, and 48.79 (± 1.56) and 67.98 (± 2.33) in Beas-2B cells. These compounds simultaneously increased ceramide levels and decreased telomerase levels in A549 cells. Ceranib-2 increased telomerase levels while decreasing ceramide levels in Beas-2B cells. It was shown how the synergistic impact of ceranib-2-induced ceramide production and ceramide-induced telomerase level reduction on cytotoxicity in A549 cells. CONCLUSIONS: Ceranib-2-SLN was discovered to be more cytotoxic on cancer cells than ceranib-2, suggesting that it could be a promising option for the development of a new anti-cancer agent.

Assuntos

Telomerase , Humanos , Telomerase/metabolismo , Telomerase/antagonistas & inibidores , Linhagem Celular Tumoral , Células A549 , Proliferação de Células/efeitos dos fármacos , Antineoplásicos/farmacologia , Ceramidas/metabolismo , Nanopartículas/química , Sobrevivência Celular/efeitos dos fármacos

RESUMO

Telomere shortening is a prominent hallmark of aging and is emerging as a characteristic feature of Myelodysplastic Syndromes (MDS) and Idiopathic Pulmonary Fibrosis (IPF). Optimal telomerase activity prevents progressive shortening of telomeres that triggers DNA damage responses. However, the upstream regulation of telomerase holoenzyme components remains poorly defined. Here, we identify RIOK2, a master regulator of human blood cell development, as a critical transcription factor for telomere maintenance. Mechanistically, loss of RIOK2 or its DNA-binding/transactivation properties downregulates mRNA expression of both TRiC and dyskerin complex subunits that impairs telomerase activity, thereby causing telomere shortening. We further show that RIOK2 expression is diminished in aged individuals and IPF patients, and it strongly correlates with shortened telomeres in MDS patient-derived bone marrow cells. Importantly, ectopic expression of RIOK2 alleviates telomere shortening in IPF patient-derived primary lung fibroblasts. Hence, increasing RIOK2 levels prevents telomere shortening, thus offering therapeutic strategies for telomere biology disorders.

Assuntos

Proteínas de Ciclo Celular , Fibrose Pulmonar Idiopática , Proteínas Nucleares , Telomerase , Encurtamento do Telômero , Humanos , Fibrose Pulmonar Idiopática/genética , Fibrose Pulmonar Idiopática/metabolismo , Fibrose Pulmonar Idiopática/patologia , Telomerase/metabolismo , Telomerase/genética , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Fibroblastos/metabolismo , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/metabolismo , Telômero/metabolismo , Telômero/genética , Regulação da Expressão Gênica , Pulmão/metabolismo , Pulmão/patologia

RESUMO

Metastasis is an important hallmark of malignant tumors, and telomerase often exhibits high expression in these tumors. Monitoring the real-time dynamics of telomerase will provide valuable insights into its association with tumor metastasis. In this study, we described a microfluidic system for screening highly metastatic sublines based on differential cell invasiveness, investigated telomerase expression in the process of tumor metastasis and explored the genes and signaling pathways involved in tumor metastasis. Cells with different metastasis abilities were efficiently classified into different channels, and the fluorescence imaging visually demonstrates that cells with higher metastasis ability have stronger telomerase activity. In addition, we successfully established the high-metastasis-ability LoVo subline (named as LoVo-H) and low-metastasis-ability LoVo subline (named as LoVo-L) from the human colorectal cancer LoVo cell lines through only one round of selection using the system. The results show that the LoVo-H cells display superior proliferation and invasiveness compared to LoVo-L cells. Furthermore, 6776 differentially expressed genes of LoVo-H compared with LoVo-L were identified by transcriptome sequencing. The genes associated with telomerase activity, cell migration and the epithelial to mesenchymal transition were up-regulated in LoVo-H, and PI3K-Akt signaling pathway, extracellular matrix-receptor interaction and Rap1 signaling pathway were significantly enriched in LoVo-H. This microfluidic system is a highly effective tool for selecting highly metastatic sublines and the LoVo-H subline established through this system presents a promising model for tumor metastasis research. Furthermore, this work preliminarily reveals telomerase expression during tumor metastasis and provides a new strategy for studying tumor metastasis and cancer diagnosis.

Assuntos

Metástase Neoplásica , Telomerase , Telomerase/metabolismo , Telomerase/genética , Humanos , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Dispositivos Lab-On-A-Chip , Técnicas Analíticas Microfluídicas/instrumentação , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Transdução de Sinais

RESUMO

Glioblastoma (GBM) is a primary CNS tumor that is highly lethal in adults and has limited treatment options. Despite advancements in understanding the GBM biology, the standard treatment for GBM has remained unchanged for more than a decade. Only 6.8% of patients survive beyond five years. Telomerase, particularly the hTERT promoter mutations present in up to 80% of GBM cases, represents a promising therapeutic target due to its role in sustaining telomere length and cancer cell proliferation. This review examines the biology of telomerase in GBM and explores potential telomerase-targeted therapies. We conducted a systematic review following the PRISMA-P guidelines in the MEDLINE/PubMed and Scopus databases, from January 1995 to April 2024. We searched for suitable articles by utilizing the terms "GBM", "high-grade gliomas", "hTERT" and "telomerase". We incorporated studies addressing telomerase-targeted therapies into GBM studies, excluding non-English articles, reviews, and meta-analyses. We evaluated a total of 777 records and 46 full texts, including 36 studies in the final review. Several compounds aimed at inhibiting hTERT transcription demonstrated promising preclinical outcomes; however, they were unsuccessful in clinical trials owing to intricate regulatory pathways and inadequate pharmacokinetics. Direct hTERT inhibitors encountered numerous obstacles, including a prolonged latency for telomere shortening and the activation of the alternative lengthening of telomeres (ALT). The G-quadruplex DNA stabilizers appeared to be potential indirect inhibitors, but further clinical studies are required. Imetelstat, the only telomerase inhibitor that has undergone clinical trials, has demonstrated efficacy in various cancers, but its efficacy in GBM has been limited. Telomerase-targeted therapies in GBM is challenging due to complex hTERT regulation and inadequate inhibitor pharmacokinetics. Our study demonstrates that, despite promising preclinical results, no Telomerase inhibitors have been approved for GBM, and clinical trials have been largely unsuccessful. Future strategies may include Telomerase-based vaccines and multi-target inhibitors, which may provide more effective treatments when combined with a better understanding of telomere dynamics and tumor biology. These treatments have the potential to be integrated with existing ones and to improve the outcomes for patients with GBM.

Assuntos

Glioblastoma , Telomerase , Telomerase/antagonistas & inibidores , Telomerase/metabolismo , Humanos , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Glioblastoma/genética , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/genética , Terapia de Alvo Molecular , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia , Telômero/metabolismo , Telômero/efeitos dos fármacos , Animais

RESUMO

Numerous studies have investigated seed aging, with a particular emphasis on the involvement of reactive oxygen species. Reactive oxygen species diffuse into the nucleus and damage telomeres, resulting in loss of genetic integrity. Telomerase reverse transcriptase (TERT) plays an essential role in maintaining plant genomic stability. Genome-wide analyses of TERT genes in alfalfa (Medicago sativa) have not yet been conducted, leaving a gap in our understanding of the mechanisms underlying seed aging associated with TERT genes. In this study, four MsTERT genes were identified in the alfalfa genome. The expression profiles of the four MsTERT genes during seed germination indicated that MS. gene79077 was significantly upregulated by seed aging. Transgenic seeds overexpressing MS. gene79077 in Arabidopsis exhibited enhanced tolerance to seed aging by reducing the levels of H2O2 and increasing telomere length and telomerase activity. Furthermore, transcript profiling of aging-treated Arabidopsis wild-type and overexpressing seeds showed an aging response in genes related to glutathione-dependent detoxification and antioxidant defense pathways. These results revealed that MS. gene79077 conferred Arabidopsis seed-aging tolerance via modulation of antioxidant defense and telomere homeostasis. This study provides a new way to understand stress-responsive MsTERT genes for the potential genetic improvement of seed vigor.

Assuntos

Arabidopsis , Regulação da Expressão Gênica de Plantas , Medicago sativa , Sementes , Telomerase , Homeostase do Telômero , Telômero , Arabidopsis/genética , Medicago sativa/genética , Telomerase/genética , Telomerase/metabolismo , Sementes/genética , Telômero/genética , Telômero/metabolismo , Plantas Geneticamente Modificadas , Germinação/genética , Peróxido de Hidrogênio/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Antioxidantes/metabolismo , Senescência Vegetal/genética

RESUMO

INTRODUCTION: Telomeres are nucleoprotein complexes at the ends of chromosomes that are under the control of genetic and environmental triggers. Accelerated telomere shortening is causally implicated in the increasing incidence of diseases. The Mediterranean diet has recently been identified as one that confers protection against diseases. This review aimed to identify the effect of each component of the Mediterranean diet on telomere length dynamics, highlighting the underlying molecular mechanisms. METHODS: PubMed was searched to identify relevant studies to extract data for conducting a narrative review. RESULTS: The Mediterranean diet alleviates clinical manifestations in many diseases. Focusing on autoimmune diseases, the Mediterranean diet can be protective by preventing inflammation, mitochondrial malfunction, and abnormal telomerase activity. Also, each Mediterranean diet constituent seems to attenuate aging through the sustenance or elongation of telomere length, providing insights into the underlying molecular mechanisms. Polyphenols, vitamins, minerals, and fatty acids seem to be essential in telomere homeostasis, since they inhibit inflammatory responses, DNA damage, oxidative stress, mitochondrial malfunction, and cell death and induce telomerase activation. CONCLUSIONS: The Mediterranean diet is beneficial for maintaining telomere dynamics and alleviating age-related illnesses. This review provides a comprehensive overview of cross-sectional, observational, and randomized controlled trials regarding the beneficial impact of every constituent in the Mediterranean diet on telomere length and chronic disease management.

Assuntos

Dieta Mediterrânea , Telômero , Humanos , Homeostase do Telômero , Encurtamento do Telômero , Envelhecimento , Telomerase/metabolismo , Gerenciamento Clínico , Estresse Oxidativo , Polifenóis , Doenças Autoimunes