Levels Of Telomerase Activity Research Articles

Different Effect of Dienogest on Endometrium Mesenchymal Stem Cells Derived from Healthy and Endometriosis Tissues

Endometriosis (EM) is an inflammatory condition in which the endometrium is observed to develop outside the uterine cavity. Endometrium has conventionally been recognized as a rich source of endometrial mesenchymal stem cells (E-MSCs). The influence of dienogest, a medication frequently prescribed for EM, on E-MSCs has not been extensively investigated. To explore effects of dienogest on the E-MSCs derived from healthy (E-MSCs-control) and diseased (E-MSCs-endometriosis) endometrial tissue samples in vitro. In vitro study. We collected samples from healthy and diseased endometrial tissues. E-MSCs were derived from both healthy and EM tissues. The effect of dienogest (VISANNE) on E-MSCs was assessed by examining cell proliferation, telomerase activity, cell migration, and estrogen secretion levels after the isolation and characterization of E-MSCs. We discovered that cellular proliferation rate was higher in the E-MSCs derived from EM tissues compared to those derived from healthy tissue. The proliferation rate and telomerase activity were both suppressed by dienogest treatment, particularly in E-MSCs-endometriosis. The drug treatment also resulted in a decrease in the migration capacity of E-MSCs-endometriosis, from 60.4% to 59.2%. The expression of CXCL12, Ki67, and beta-catenin was analyzed in both E-MSCs-endometriosis and E-MSCs-control. The CXCL12 and Ki67 expressions were quite elevated in the E-MSCs-endometriosis without drug treatment compared to the E-MSCs-control. Following the treatment, these levels declined drastically to the levels close to E-MSCs-control. Similarly, this decrease in gene expression was accompanied by a decrease in estrogen secretion into the medium. This research demonstrates that dienogest exerts a substantial impact on both stromal and stem cells, as it effectively controls the disease by reversing EM markers, despite the absence of progesterone receptors on endometrial stem cells.

P-501 Superovulation alters telomere length and telomerase expression in mouse oocytes, possibly by changing estradiol and progesterone levels

Abstract Study question How does the single and repeated superovulation affect the telomerase components expression and telomere length in mouse GV and MII oocytes? Summary answer Superovulation significantly altered the expression of the telomerase components Tert and Terc genes, TERT protein levels, and telomere length in the GV and MII oocytes. What is known already Assisted reproductive technologies (ARTs) are commonly used to treat infertility problems. One of the basic ART steps is controlled ovarian stimulation, also known as superovulation. Superovulation can lead to several adverse effects, such as increased oxidative stress, decreased oocyte and embryo quality, and mitochondrial dysfunction. These effects of superovulation largely overlap with those that causing telomere shortening. Study design, size, duration The effect of superovulation on the telomerase expression and telomere length of GV and MII oocytes is not fully addressed yet. In this study, we investigated the potential effects of single and repeated superovulation on telomerase expression and telomere length in mouse oocytes at germinal vesicle (GV) and metaphase II (MII) stages. In addition, we measured the estradiol and progesterone as well as oxidant and antioxidant capacity in serum samples of the oocytes-collected mice. Participants/materials, setting, methods Four groups of female Balb/C mice were formed: Control (C; n = 12), superovulated once (1S; n = 12), superovulated three times (3S; n = 12), and superovulated five times (5S; n = 12) at one-week intervals. The Tert and Terc gene expression, TERT protein levels, and telomere length in the mouse oocytes were assessed by RT-qPCR, immunofluorescence, and q-PCR, respectively. The hormone levels were analyzed by ELISA, and oxidant-antioxidant capacities were measured. All the ovarian follicles were counted in the H&E stained-sections. Main results and the role of chance We found that superovulation (1S, 3S, and 5S) significantly altered expression of the telomerase components Tert and Terc genes, TERT protein levels, and telomere length in the GV and MII oocytes (P<0.05). While estradiol levels in GV oocyte-collected and progesterone levels of GV and MII oocyte-collected mice were higher in the 1S, 3S, and 5S groups compared with the C group (P<0.01), the estradiol levels in MII oocyte-collected mice decreased progressively from C to 5S groups (P<0.01). However, no significant changes were found in the total oxidant status (TOS), antioxidant status (TAS), and oxidative stress index (OSI) between the groups. Also, primordial and atretic follicle numbers in the ovaries of 3S and 5S groups were significantly decreased compared to the control and 1S groups (P<0.05). Limitations, reasons for caution The limitation of this study is that we could not evaluate telomerase activity and oxidative stress levels in the mouse oocytes. Wider implications of the findings All these results suggest that altered telomerase expression and telomere length in GV and MII oocytes, possibly due to changed estradiol and progesterone levels, may be associated with adverse effects of superovulation on oocyte maturation and even preimplantation embryo development. Trial registration number not applicaple

Neratinib stimulates senescence of mammary cancer cells by reducing the levels of SIRT1.

Neratinib, a typical small-molecule, pan-human tyrosine kinase inhibitor (TKI), has been licensed for the treatment of human epidermal growth factor receptor 2 (HER2)-positive breast cancer. However, the underlying pharmacological mechanism is still unknown. In the current study, we report a novel function of Neratinib by showing that its treatment stimulates senescence of the mammary cancer AU565 cells. Our results demonstrate that Neratinib induces mitochondrial injury by increasing mitochondrial reactive oxygen species (ROS) and reducing intracellular adenosine triphosphate (ATP). Also, we found that Neratinib induced DNA damage by increasing the levels of 8-Hydroxy-desoxyguanosine (8-OHdG) and γH2AX in AU565 cells. Additionally, Neratinib reduced the levels of telomerase activity after 7 and 14 days incubation. Importantly, the senescence-associated-β-galactosidase (SA-β-Gal) assay revealed that Neratinib stimulated senescence of AU565 cells. Neratinib decreased the gene levels of human telomerase reverse transcriptase (hTERT) but increased those of telomeric repeat-binding factor 2 (TERF2) in AU565 cells. Further study displayed that Neratinib upregulated the expression of K382 acetylation of p53 (ac-K382) and p21 but reduced the levels of sirtuin-1 (SIRT1). However, overexpression of SIRT1 abolished the effects of Neratinib in cellular senescence. These findings provide strong preclinical evidence of Neratinib's treatment of breast cancer.

Arabidopsis AN3 and OLIGOCELLULA genes link telomere maintenance mechanisms with cell division and expansion control.

Telomeres are conserved chromosomal structures necessary for continued cell division and proliferation. In addition to the classical telomerase pathway, multiple other genes including those involved in ribosome metabolism and chromatin modification contribute to telomere length maintenance. We previously reported that Arabidopsis thaliana ribosome biogenesis genes OLI2/NOP2A, OLI5/RPL5A and OLI7/RPL5B have critical roles in telomere length regulation. These three OLIGOCELLULA genes were also shown to function in cell proliferation and expansion control and to genetically interact with the transcriptional co-activator ANGUSTIFOLIA3 (AN3). Here we show that AN3-deficient plants progressively lose telomeric DNA in early homozygous mutant generations, but ultimately establish a new shorter telomere length setpoint by the fifth mutant generation with a telomere length similar to oli2/nop2a -deficient plants. Analysis of double an3 oli2 mutants indicates that the two genes are epistatic for telomere length control. Telomere shortening in an3 and oli mutants is not caused by telomerase inhibition; wild type levels of telomerase activity are detected in all analyzed mutants in vitro. Late generations of an3 and oli mutants are prone to stem cell damage in the root apical meristem, implying that genes regulating telomere length may have conserved functional roles in stem cell maintenance mechanisms. Multiple instances of anaphase fusions in late generations of oli5 and oli7 mutants were observed, highlighting an unexpected effect of ribosome biogenesis factors on chromosome integrity. Overall, our data implicate AN3 transcription coactivator and OLIGOCELLULA proteins in the establishment of telomere length set point in plants and further suggest that multiple regulators with pleiotropic functions can connect telomere biology with cell proliferation and cell expansion pathways.

Novel protective effect of the FOXO3 longevity genotype on mechanisms of cellular aging in Okinawans

The genetic association of FOXO3 genotypes with human longevity is well established, although the mechanism is not fully understood. We now report on the relationship of the FOXO3 longevity variant rs2802292 with telomere length, telomerase activity, FOXO3 expression, and inflammatory cytokine levels in men and women. In agreement with earlier work, the FOXO3 longevity variant conferred protection against telomere shortening of peripheral blood mononuclear cells from adults aged 55 years and older. This was accompanied by higher levels of telomerase activity in mononuclear cells for carriers of the longevity-associated FOXO3 G-allele of SNP rs2802292 (P = 0.015). FOXO3 mRNA expression increased slightly with age in both young (P = 0.02) and old (P = 0.08) G-allele carriers. Older female G-allele carriers displayed a modest decline in levels of pro-inflammatory cytokine IL-6 with age (P = 0.07). In contrast, older male G-allele carriers displayed an age-dependent increase in levels of anti-inflammatory cytokine IL-10 with age (P = 0.04). Thus, FOXO3 may act through several different pro-longevity mechanisms, which may differ by age and sex.

Comparing Length and Telomere Expression at Oral Precancerous and Cancerous Stages.

Telomeres consist of repetitive G-rich nucleotides located at the end of each chromosome, acting as protein binding sites. The aim of this study was to examine the differences in telomere length in blood, saliva, and tissue samples at various stages of oral precancerous and cancerous lesions. Samples of blood, tissue, and saliva were collected from patients with oral precancerous and cancerous lesions. DNA extraction was performed. Then, a TRAP assay was conducted to assess and compare the telomere length and telomerase expression. The levels of telomerase activity (TA) in the DNA samples ranged from 0.19 to 6.91 (2.05+1.37) among oral squamous cell carcinoma (OSCC) patients and from 0.17 to 4.5 (0.28+4.25) among precancerous patients. A significant difference was observed in TA levels between OSCC and precancerous samples (t=3.9691, P= 0.0000). Assessing the telomerase activity is crucial for studying the behavior of carcinoma in the clinical setting. The augmented telomerase expression and the length of telomere contribute to OSCC progression. Hence, this study adds a diagnostic tool that can serve as a biomarker for the early detection and prognosis of OSCC.

Активность теломеразы, гиперлипидемия и особенности атеросклеротического поражения брахиоцефальных артерий у бессимптомных пациентов трудоспособного возраста с субклиническим гипотиреозом

Aim. To study telomerase activity, lipidemia and to assess the severity of atherosclerotic lesions of the brachiocephalic arteries in asymptomatic patients of working age with subclinical hypothyroidism. Design. A cross-sectional cohort study. Materials and methods. Data on 131 patients of working age (32 men and 99 women) with different hormonal status of the thyroid gland (thyroid) without clinical signs of chronic cerebral circulatory insufficiency were analyzed. Based on the assessment of the hormonal status of the thyroid gland, 2 groups of patients were formed: 87 with laboratory-confirmed hypertension (thyroid-stimulating hormone level > 4.0 mMU/l with normal characteristics of free fractions of thyroid hormones) and 44 patients without thyroid dysfunction. The groups formed were comparable in age, gender composition, presence and severity of hypertension, aggravated family history of early cardiovascular events, and smoking. All patients underwent ultrasound examination of the brachiocephalic arteries, determination of the lipid spectrum and telomerase concentration. The processing of the obtained data was carried out using statistical packages Excel, Statistica v. 10.0. The data obtained were interpreted as reliable, and the differences between the indicators were considered significant when the error-free prediction value was equal to or greater than 95% (p < 0.05). Results. In the group of people with hypothyroidism, the proportion of people with multivessel atherosclerotic lesion was higher (34.5% (n = 30) vs. 13.6% (n = 6) (χ2 = 6.37; p < 0.05)), one or a combination of several signs of instability of atherosclerotic plaque (41.4% (n = 36) vs. 18.2% (n = 8) (χ2 = 7.05; p < 0.01)). In patients with subclinical hypothyroidism, precerebral atherosclerosis occurs against the background of atherogenic type IIa secondary hyperlipidemia (67.8% (n = 59) vs. 34.1% (n = 6) (χ2 = 13.52; p < 0.001) in combination with insufficiency of antiatherogenic high density lipoproteins (74.7% (n = 65) vs. 45.5% (n = 20) (χ2 = 10.98; p < 0.001)), lower values of telomerase concentration in comparison with the group of people without thyroid dysfunction: (8.2 (7.4–9.5) vs. 10.8 (10.1–12.2) ng/ml (p < 0.001)). The relationship between the level of telomerase activity (r = –0.72; p < 0.05) and the presence of subclinical hypothyroidism, atherosclerotic lesions of the precerebral bed in patients (r = –0.33; p < 0.05) was established. Conclusion. In clinically healthy patients of working age with newly diagnosed, medically uncorrected subclinical hypothyroidism, the proportion of persons with ultrasound signs of multivessel atherosclerotic lesions of the brachiocephalic arteries is higher, and precerebral atherosclerosis occurs against the background of atherogenic type IIa secondary hyperlipidemia in combination with insufficiency of antiatherogenic high density lipoproteins, lower values of telomerase activity in comparison with the group of persons without thyroid dysfunction. Etiopathogenetic mechanisms of "early vascular aging", the criteria for stratification of risk groups for atherosclerosis-associated cardiovascular disease, the choice of diagnostic algorithms for visualizing preclinical stages of atherogenesis, and timely antiatherogenic tactics in asymptomatic patients with comorbid thyroid pathology require further study. Verification of a stenosing hemodynamically significant or non-hemodynamically significant atherosclerotic lesion of the coronary basin, regardless of the clinical component, is a factor of high cardiovascular risk requiring immediate correction of hyperlipidemia. Keywords: thyroid gland, hypothyroidism, hyperlipidemia, atherosclerosis, precerebral (brachiocephalic) arteries, telomerase activity, comorbid pathology.

Arabidopsis telomerase takes off by uncoupling enzyme activity from telomere length maintenance in space

Spaceflight-induced changes in astronaut telomeres have garnered significant attention in recent years. While plants represent an essential component of future long-duration space travel, the impacts of spaceflight on plant telomeres and telomerase have not been examined. Here we report on the telomere dynamics of Arabidopsis thaliana grown aboard the International Space Station. We observe no changes in telomere length in space-flown Arabidopsis seedlings, despite a dramatic increase in telomerase activity (up to 150-fold in roots), as well as elevated genome oxidation. Ground-based follow up studies provide further evidence that telomerase is induced by different environmental stressors, but its activity is uncoupled from telomere length. Supporting this conclusion, genetically engineered super-telomerase lines with enhanced telomerase activity maintain wildtype telomere length. Finally, genome oxidation is inversely correlated with telomerase activity levels. We propose a redox protective capacity for Arabidopsis telomerase that may promote survivability in harsh environments.

Seasonal variation in telomerase activity and telomere dynamics in a hibernating rodent, the garden dormouse (Eliomys quercinus).

Telomere dynamics in hibernating species are known to reflect seasonal changes in somatic maintenance. Throughout hibernation, the periodic states of rewarming, known as inter-bout euthermia or arousals, are associated with high metabolic costs including shortening of telomeres. In the active season, if high energetic resources are available, telomere length can be restored in preparation for the upcoming winter. The mechanism for telomere elongation has not been clearly demonstrated, although the action of the ribonucleoprotein complex, telomerase, has been implicated in many species. Here we tested for levels of telomerase activity in the garden dormouse (Eliomys quercinus) at different seasonal time points throughout the year and across ages from liver tissues of male juveniles to adults. We found that telomerase is active at high levels across seasons (during torpor and inter-bout euthermia, plus in the active season) but that there was a substantial decrease in activity in the month prior to hibernation. Telomerase levels were consistent across age groups and were independent of feeding regime and time of birth (early or late born). The changes in activity levels that we detected were broadly associated with changes in telomere lengths measured in the same tissues. We hypothesise that i) telomerase is the mechanism used by garden dormice for maintenance of telomeres and that ii) activity is kept at high levels throughout the year until pre-hibernation when resources are diverted to increasing fat reserves for overwintering. We found no evidence for a decrease in telomerase activity with age or a final increase in telomere length which has been detected in other hibernating rodents.

THE FOXO3 LONGEVITY GENOTYPE PROTECTS AGAINST MECHANISMS OF CELLULAR AGING IN OKINAWANS

Abstract The genetic association of FOXO3 genotypes with human longevity is well established, although the mechanism is not fully understood. We now report on the relationship of the FOXO3 longevity variant rs2802292 with telomere length, telomerase activity, FOXO3 expression and inflammatory cytokine levels in men and women. In agreement with earlier work, the FOXO3 longevity variant conferred protection against telomere shortening of peripheral blood mononuclear cells from adults aged 55 and older. This was accompanied by higher levels of telomerase activity in carriers of the longevity-associated FOXO3 G-allele (P=0.015). FOXO3 mRNA expression increased slightly with age in both young (P=0.02) and old (P=0.08) G-allele carriers. Older female G-allele carriers displayed a modest decline in levels of pro-inflammatory cytokine IL-6 with age (P=0.07). In contrast, older male G-allele carriers displayed an age-dependent increase in levels of anti-inflammatory cytokine IL-10 with age (P=0.04). Thus, FOXO3 may act through several different pro-longevity mechanisms, which may differ by age and sex.

Abstract A09: Telomerase activity as a biomarker to predict outcomes of CAR T-cell therapy

Abstract Introduction: Chimeric antigen receptor T-cells (CAR T-cells) and T-cells in general, remain in a quiescent state when unstimulated, showing no proliferative activity. In contrast, upon specific antigenic stimulation, CAR T-cells rapidly divide and kill their target cancer cells. However, one of the immunologic changes with aging is the progressive impairment of T-cell responses. This physiologic immunosenescence is associated with the shortening of telomeres. The telomerase enzyme is transiently upregulated in stimulated CAR T-cells preventing dramatic telomere shortening during rapid CAR T-cell division. Our previous study showed that during T-cell expansion, the period during which telomerase is active and the magnitude of its activity correlates with the donor’s age and overall health status (“healthy aging”) [1]. The aim of this study is to investigate whether the magnitude of telomerase activity in stimulated CAR T-cells is a predictive biomarker of outcomes in patients receiving CAR T-cell therapy.Methods: The study population comprises of older adult patients (age range: 50-84 years) receiving autologous anti-CD19 CAR T-cell therapy for relapsed or refractory diffuse large B-cell lymphoma, mantle cell lymphoma or follicular lymphoma. Peripheral blood samples are collected from patients pre-lymphodepletion and T-cells isolated from PBMCs (peripheral blood mononuclear cells). CAR T-cells are then generated from patient T-cells in the lab and telomerase activity analyzed over 2 weeks in culture. For each patient’s CAR T-cells, absolute values of telomerase activity are plotted to calculate the area under the curve (AUC). We are investigating the potential correlation of AUC of telomerase activity to disease response at 30- and 90-days post CAR T-cell infusion. Results: Preliminary data from eight patients is showing a clear correlation between telomerase activity and patient outcomes. Robust telomerase activity shows a positive correlation with complete responses on day 30 PET-CT scans and sustained clinical remission, while poor telomerase activity correlates with no response or progressive disease. We are expanding our study sample to 30-50 patients and updated data will be presented at the meeting. Conclusions: CAR T-cell therapy has been a game-changer for hematological malignancies; however therapeutic resistance and disease relapse remains a major concern. Understanding the mechanisms of resistance to CAR T-cell therapy is critical for advancing the field. Telomerase activity levels could be a potential predictive biomarker for CAR T-cell therapy outcomes and aid in personalizing treatment choices. Furthermore, future research on increasing telomerase activity may enhance CAR T-cell therapy function and ultimately patient outcomes. [1] Tedone et.al, Telomere length and telomerase activity in T cells are biomarkers of high-performing centenarians, Aging Cell, 2019 Citation Format: Mohammed E Sayed, Enzo Tedone, Emily Zhang, Helen Stephens, Farrukh T Awan, Jerry Shay, Praveen Ramakrishnan Geethakumari. Telomerase activity as a biomarker to predict outcomes of CAR T-cell therapy [abstract]. In: Proceedings of the Third AACR International Meeting: Advances in Malignant Lymphoma: Maximizing the Basic-Translational Interface for Clinical Application; 2022 Jun 23-26; Boston, MA. Philadelphia (PA): AACR; Blood Cancer Discov 2022;3(5_Suppl):Abstract nr A09.

Comparison of urinary telomerase, CD44, and NMP22 assays for detection of bladder squamous cell carcinoma.

BackgroundSquamous cell carcinoma (SCC) of the bladder is common in many regions around the world. Prognosis is very poor, as most cases are diagnosed at an advanced stage due to a lack of affordable and valid screening markers for this type of cancer. The diagnostic accuracy of urinary nuclear matrix protein-22 (NMP22), telomerase activity, and CD44 were evaluated in urine samples of patients with bladder SCC.Materials and methodsWe conducted a case-control study comprised of 60 consecutive newly diagnosed bladder SCC patients diagnosed by cystoscopy and histopathological examination, and controls were 60 outpatients with benign urologic conditions and healthy clinic visitors. Urine samples collected from each subject underwent testing for NMP22, telomerase activity, and CD44. Descriptive and correlational statistical analysis of cases and controls were carried out and receiver operating characteristic curve analysis was used to determine optimal cut-off points for the three assays.ResultsArea under the curve was calculated at 0.96, 0.93, and 0.62 for NMP22, telomerase, and CD44, respectively. Urine levels of NMP22 and telomerase activity were significantly higher in the SCC group compared to controls (p < 0.001). Urine CD44 levels were not significantly higher in the SCC group compared to controls (p = 0.111). The overall sensitivity of NMP22, telomerase, and CD44 was 96.7%, 87%, and 45%, respectively, while the specificity was 85%, 88.6%, and 86.7%, respectively.ConclusionsUrinary telomerase activity, followed by NMP22 urine levels, showed high diagnostic yield and could hold potential promise as urinary biomarkers for the diagnosis of bladder SCC.

Short and Long-Term Interval Effects of High-Intensity Interval Training on Pathways Related to Telomere Homeostasis in Rat Skeletal Muscle

Background: Exercise training through various mechanisms leads to correct telomere homeostasis. The potential role of high-intensity interval training (HIIT) to keep up the telomere length has not been recognized in skeletal muscle. Objectives: This study investigated the influence of eight weeks of HIIT with short-term interval (HIITSh) and long-term interval (HIITL), and four weeks of detraining on the regulation of some pathways maintaining telomere length in skeletal muscle. Methods: Fifty-four male Wistar rats were randomly assigned into HIITSh, HIITL, and control groups. Rats were sacrificed after the end of the intervention (eight weeks of training and four weeks of detraining). Gastrocnemius muscle was collected, and telomerase activity, p53 protein, total oxidative status (TOS), and total antioxidant capacity (TAC) levels were measured. Results: We found no change in telomerase activity, p53, TOS, and TAC levels in both HIIT groups compared to the control group (P &gt; 0.05). In addition, the p53 level was higher in the detrained HIITSh group than the control group (P = 0.004), and the TOS level was higher in the detrained HIITSh group than both HIIT groups. Conclusions: Short-term HIIT does not improve telomere length and some pathways contributing to maintaining telomere length in skeletal muscle. The training protocol’s duration is an essential factor in activating telomerase as a mechanism to keep up telomere length in skeletal muscle.

Investigating the Long-Term Effect of an Interdisciplinary Multimodal Rehabilitation Program on Levels of Bioactive Lipids and Telomerase Activity in Blood from Patients with Chronic Pain.

Mechanism-based diagnosis and therapies for chronic pain are lacking. However, bio-psycho-social interventions such as interdisciplinary multimodal rehabilitation programs (IPRPs) have shown to be relatively effective treatments. In this context we aim to investigate the effects of IPRP on the changes in levels of bioactive lipids and telomerase activity in plasma, and if these changes are associated with changes in pain intensity and psychological distress. This exploratory study involves 18 patients with complex chronic pain participating in an IPRP. Self-reports of pain, psychological distress, physical activity, and blood samples were collected before the IPRP and at a six-month follow-up. Levels of arachidonoylethanolamide (AEA) and 2-arachidonoylglycerol (2-AG), palmitoylethanolamide (PEA), oleoylethanolamide (OEA), stearoylethanolamide (SEA), and telomerase activity were measured. Pain intensity was decreased, and SEA levels were increased at the six-month follow up. A significant correlation existed between changes in SEA levels and pain intensity. AEA levels, were inversely correlated with physical activity. Furthermore, 2-AG and telomerase activity was significantly correlated at the six-month follow-up. This study confirms that IPRP is relatively effective for reduction in chronic pain. Changes in SEA were correlated with changes in pain intensity, which might indicate that SEA changes reflect the pain reduction effects of IPRP.

Effects of FOXO3 on Markers of Aging in Blood : An Okinawan Longevity Cohort Study

FOXO3 is among only a few genes that demonstrate a consistently reproducible genetic association with human longevity. We previously demonstrated, in a cross-sectional study of Okinawan Japanese, that the principal longevity variant of FOXO3 (rs 2802292 “G allele”) protects against age-associated attrition of telomere length. We now expand upon this initial observation in a more detailed cross-sectional analysis of the effect of FOXO3 on telomerase activity, FOXO3 expression and inflammatory cytokine levels in both men and women. In agreement with our initial study, we found the FOXO3 longevity variant conferred significant protection against telomere shortening to roughly the same degree in elderly (ages 55 and older) men and women. Carriers of the G - allele also had slightly higher levels of blood telomerase activity in young (ages 20 – 54) and elderly participants (P≤0.1). The expression (mRNA) of FOXO3 increased steadily with age in young and old G – allele carriers (borderline P≤0.08), in contrast to a lack of association with age in non-carriers. The FOXO3 G - allele was also observed to significantly impact levels of both interleukin 6 (IL 6) and IL10, but in a sex dependent manner (P<0.05). These sex-specific effects may point to different mechanisms by which FOXO3 exerts its effect on longevity in men and women.

Reciprocal impacts of telomerase activity and ADRN/MES differentiation state in neuroblastoma tumor biology

Telomere maintenance and tumor cell differentiation have been separately implicated in neuroblastoma malignancy. Their mechanistic connection is unclear. We analyzed neuroblastoma cell lines and morphologic subclones representing the adrenergic (ADRN) and mesenchymal (MES) differentiation states and uncovered sharp differences in their telomere protein and telomerase activity levels. Pharmacologic conversion of ADRN into MES cells elicited consistent and robust changes in the expression of telomere-related proteins. Conversely, stringent down-regulation of telomerase activity triggers the differentiation of ADRN into MES cells, which was reversible upon telomerase up-regulation. Interestingly, the MES differentiation state is associated with elevated levels of innate immunity factors, including key components of the DNA-sensing pathway. Accordingly, MES but not ADRN cells can mount a robust response to viral infections in vitro. A gene expression signature based on telomere and cell lineage-related factors can cluster neuroblastoma tumor samples into predominantly ADRN or MES-like groups, with distinct clinical outcomes. Our findings establish a strong mechanistic connection between telomere and differentiation and suggest that manipulating telomeres may suppress malignancy not only by limiting the tumor growth potential but also by inducing tumor cell differentiation and altering its immunogenicity.

Efficacy of decitabine in malignant meningioma cells: relation to promoter demethylation of distinct tumor suppressor and oncogenes and independence from TERT.

Chemotherapeutic options for meningiomas refractory to surgery or irradiation are largely unknown. Human telomerase reverse transcriptase (hTERT) promoter methylation with subsequent TERT expression and telomerase activity, key features in oncogenesis, are found in most high-grade meningiomas. Therefore, the authors investigated the impact of the demethylating agent decitabine (5-aza-2'-deoxycytidine) on survival and DNA methylation in meningioma cells. hTERT promoter methylation, telomerase activity, TERT expression, and cell viability and proliferation were investigated prior to and after incubation with decitabine in two benign (HBL-52 and Ben-Men 1) and one malignant (IOMM-Lee) meningioma cell line. The global effects of decitabine on DNA methylation were additionally explored with DNA methylation profiling. High levels of TERT expression, telomerase activity, and hTERT promoter methylation were found in IOMM-Lee and Ben-Men 1 but not in HBL-52 cells. Decitabine induced a dose-dependent significant decrease of proliferation and viability after incubation with doses from 1 to 10 μM in IOMM-Lee but not in HBL-52 or Ben-Men 1 cells. However, effects in IOMM-Lee cells were not related to TERT expression, telomerase activity, or hTERT promoter methylation. Genome-wide methylation analyses revealed distinct demethylation of 14 DNA regions after drug administration in the decitabine-sensitive IOMM-Lee but not in the decitabine-resistant HBL-52 cells. Differentially methylated regions covered promoter regions of 11 genes, including several oncogenes and tumor suppressor genes that to the authors' knowledge have not yet been described in meningiomas. Decitabine decreases proliferation and viability in high-grade but not in benign meningioma cell lines. The effects of decitabine are TERT independent but related to DNA methylation changes of promoters of distinct tumor suppressor genes and oncogenes.

Potential of Naturally Derived Compounds in Telomerase and Telomere Modulation in Skin Senescence and Aging.

Proper functioning of cells—their ability to divide, differentiate, and regenerate—is dictated by genomic stability. The main factors contributing to this stability are the telomeric ends that cap chromosomes. Telomere biology and telomerase activity have been of interest to scientists in various medical science fields for years, including the study of both cancer and of senescence and aging. All these processes are accompanied by telomere-length modulation. Maintaining the key levels of telomerase component (hTERT) expression and telomerase activity that provide optimal telomere length as well as some nontelomeric functions represents a promising step in advanced anti-aging strategies, especially in dermocosmetics. Some known naturally derived compounds contribute significantly to telomere and telomerase metabolism. However, before they can be safely used, it is necessary to assess their mechanisms of action and potential side effects. This paper focuses on the metabolic potential of natural compounds to modulate telomerase and telomere biology and thus prevent senescence and skin aging.

Intron 4\u20135 hTERT DNA Hypermethylation in Merkel Cell Carcinoma: Frequency, Association with Other Clinico-pathological Features and Prognostic Relevance

Merkel cell carcinoma (MCC) is an aggressive skin tumor with neuroendocrine differentiation, mainly affecting elderly population or immunocompromised individuals. As methylation of the human telomerase reverse transcriptase (mhTERT) has been shown to be a prognostic factor in different tumors, we investigated its role in MCC, in particular in intron 4–5 where rs10069690 has been mapped and recognized as a cancer susceptibility locus. DNA methylation analysis of hTERT gene was assessed retrospectively in a cohort of 69 MCC patients from the University of Bologna, University of Turin and University of Insubria. Overall mortality was evaluated with Kaplan-Meier curves and multivariable Royston-Parmar models. High levels of mhTERT (mhTERThigh) (HR = 2.500, p = 0.015) and p63 (HR = 2.659, p = 0.016) were the only two clinico-pathological features significantly associated with a higher overall mortality at the multivariate analysis. We did not find different levels of mhTERT between MCPyV (+) and (−) cases (21 vs 14, p = 0.554); furthermore, mhTERThigh was strongly associated with older age (80.5 vs 72 years, p = 0.026), no angioinvasion (40.7% vs 71.0%, p = 0.015), lower Ki67 (50 vs 70%, p = 0.005), and PD-L1 expressions in both tumor (0 vs 3%, p = 0.021) and immune cells (0 vs 10%, p = 0.002). mhTERT is a frequently involved epigenetic mechanism and a relevant prognostic factor in MCC. In addition, it belongs to the shared oncogenic pathways of MCC (MCPyV and UV-radiations) and it could be crucial, together with other epigenetic and genetic mechanisms as gene amplification, in determining the final levels of hTERT mRNA and telomerase activity in these patients.

Detection of Urothelial Bladder Cancer Based on Urine and Tissue Telomerase Activity Measured by Novel RT-TRAP-2PCR Method.

Purpose: To assess the diagnostic performance of urine telomerase activity (TA) in detecting bladder cancer (BCa) using the modified Telomeric Repeat Amplification Protocol (TRAP) and the Real Time Telomeric Repeat Amplification Protocol with double Polymerase Chain Reaction (RT-TRAP-2PCR). Methods: In this case-control study, matching urine (in the pre- and post-surgical period) and tissue samples from 68 patients with BCa were assessed for TA. As a control, 45 urine samples were examined from non-BCa patients. TA levels were measured using TRAP and RT-TRAP-2 PCR methods. Results: Preoperative urinary TA was elevated in 64 (94.1%) of the 68 BCa patients. Urine TA was undetectable in 44 control patients, while TA was detected in one patient with histologically verified cystitis. Sensitivity for BCa detection of 94.1% and specificity of 97.8% were observed for urinary TA, while tissue TA had 100% sensitivity and 97.8% specificity. Both urine and tissue TA levels were not significantly higher in patients with muscle-invasive disease compared to those with non-muscle invasive BCa (p > 0.05). Urine and tissue TA levels were not associated with higher tumor grade, stage, and number of tumors (p > 0.05). However, the association was found between higher urinary and tissue TA levels with tumor size ≥ 3 cm (p = 0.02 and p = 0.01, respectively). During the first postoperative year, 17 BCa patients experienced disease recurrence, and urinary TA was present in 14 (82.4%) of these patients. The sensitivity and specificity of urinary TA levels for BCa recurrence in patients with non-muscle invasive bladder cancer (NMIBC) during follow-up were 82% and 94.4%, respectively. Conclusions: This pilot study demonstrates a high diagnostic performance of urinary and tissue TA levels measured by a new RT-TRAP-2PCR method for detecting and monitoring BCa. Additionally, the association was found between higher urinary and tissue TA levels with tumor size ≥ 3 cm; however, higher TA levels failed for significant correlation with advanced tumor stage and grade. Our study could serve as a benchmark for the evaluation of novel biomarkers using the RT-TRAP-2PCR method.