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1.
Rev. Ciênc. Méd. Biol. (Impr.) ; 20(3): 480-484, dez 20, 2021. fig
Article in Portuguese | LILACS | ID: biblio-1354354

ABSTRACT

Introdução: o gene TERT codifica a subunidade catalítica da telomerase responsável pelo alongamento dos telômeros no final dos cromossomos. Mutações na região promotora do gene TERT resultam em superexpressão da subunidade catalítica e promovem aumento da atividade da telomerase, fatos que levam ao aumento da incidência do câncer. No carcinoma anaplásico da tireoide, essas mutações são preditores de pior prognóstico e estão associadas a comportamento clínico agressivo, incluindo alta frequência de recidivas, metástases a distância e morte específica pela doença. Objetivo: relatar o caso de uma paciente idosa portadora de carcinoma anaplásico da tireoide, cujo teste de sequenciamento genético revelou a mutação do promotor TERT C228T. Caso clínico: mulher idosa, 66 anos, diagnosticada inicialmente com nódulo tireoidiano, o qual cresceu rapidamente em um curto período de tempo. Diante da suspeita de neoplasia maligna, a paciente foi submetida a tireoidectomia total, com realização de esvaziamento cervical. Os estudos anatomopatológico e imuno-histoquímico do tumor confirmaram o carcinoma. Estudos moleculares realizados a partir da tecnologia do sequenciamento de nova geração negaram a presença de fusões gênicas, porém detectaram a mutação TERT C228T. Discussão: a identificação da mutação no promotor TERT C288T reforça a hipótese de que mutações TERT são frequentes em tumores tireoidianos mais agressivos, como é o caso do carcinoma anaplásico da tireoide. Conclusão: os dados apresentados neste estudo reforçam a premissa de que mutações no promotor TERT são preditores de pior prognóstico e de comportamento clínico mais agressivo.


Introduction: the TERT gene encodes the catalytic telomerase subunit responsible for elongating telomeres at the end of chromosomes. Mutations in the promoter region of the TERT gene result in overexpression of the catalytic subunit and promote increased telomerase activity, facts that lead to an increased incidence of cancer. In anaplastic thyroid carcinoma, these mutations are predictors of worse prognosis and are associated with aggressive clinical behavior, including a high frequency of relapses, distant metastases, and diseasespecific death. Objective: to report the case of an elderly patient with anaplastic thyroid carcinoma, whose gene sequencing test revealed a TERT C228T promoter mutation. Case report: Elderly woman, 66 years old, initially diagnosed with a thyroid nodule, which grew rapidly in a short period of time. Given the suspicion of malignant neoplasm, the patient underwent total thyroidectomy, with neck dissection. The anatomopathological and immunohistochemical studies of the tumor confirmed the carcinoma. Molecular studies performed using next-generation sequencing technology denied the presence of gene fusions, but detected the TERT C228T mutation. Discussion: identification of the mutation in the TERT C288T promoter reinforces the hypothesis that TERT mutations are frequent in more aggressive thyroid tumors, such as anaplastic thyroid carcinoma. Conclusion: data presented in this study reinforce the premise that mutations in the TERT promoter are predictors of worse prognosis and more aggressive clinical behavior.


Subject(s)
Humans , Female , Aged , Thyroidectomy , Telomerase , Thyroid Carcinoma, Anaplastic , Mutation , Genes
2.
Journal of Experimental Hematology ; (6): 1056-1064, 2021.
Article in Chinese | WPRIM | ID: wpr-888518

ABSTRACT

OBJECTIVE@#To investigate the cytotoxic effect and its mechanism of the micromolecule compound on the leukemia cells.@*METHODS@#The cytotoxic effects of 28 Nilotinib derivatives on K562, KA, KG, HA and 32D cell lines were detected by MTT assays, and the compound Nilo 22 was screen out. Cell apoptosis and cell cycle on leukemia cells were detected by flow cytometry. The effect of compound screened out on leukemogenesis potential of MLL-AF9 leukemia mice GFP@*RESULTS@#Nilo 22 serves as the most outstanding candidate out of 28 Nilotinib derivatives, which impairs leukemia cell lines, but spares normal hematopoietic cell line. Comparing with Nilotinib, Nilo 22 could induce the apoptosis of GFP@*CONCLUSION@#Nilo 22 shows a significant cytotoxic effect on mice and human leukemia cells, especially for drug resistance cells. Nilo 22 is a promising anti-leukemia agent to solve the common clinical problems of drug resistance and relapse of leukemia.


Subject(s)
Animals , Apoptosis/drug effects , Cell Cycle/drug effects , Cell Line, Tumor , Humans , Leukemia , Mice , Myeloid-Lymphoid Leukemia Protein/genetics , Telomerase/metabolism , Telomere/metabolism
3.
Clinics ; 76: e2432, 2021. tab, graf
Article in English | LILACS | ID: biblio-1153954

ABSTRACT

OBJECTIVES: Telomeres are a terminal "DNA cap" that prevent chromosomal fusion and degradation. However, aging is inherent to life, and so is the loss of terminal sequences. Telomerase is a specialized reverse transcriptase encoded by self-splicing introns that counteract chromosome erosion. Telomerase activity is observed during early embryonic development, but after the blastocyst stage, the expression of telomerase reduces. The consequences of either insufficient or unrestrained telomerase activity underscore the importance of ongoing studies aimed at elucidating the regulation of telomerase activity in humans. In the present study, we aimed to standardize a simplified telomerase repeat-amplification protocol (TRAP) assay to detect telomerase activity in unstimulated and PHA-stimulated mononuclear cells. METHODS and RESULTS: Our optimized qPCR-based can efficiently evaluate telomerase activity. Quantification of protein and DNA between unstimulated and PHA-stimulated peripheral blood mononuclear cells revealed cellular activation and cell-cycle entry. The assay also showed that relative telomerase activity is significantly different between these two conditions, supporting the applicability of the assay. Furthermore, our findings corroborated that telomerase activity decreases with age. CONCLUSIONS: Telomeres and telomerase are implicated in aging and development of chronic diseases and cancer; however, difficulty in accessing commercial kits to investigate these aspects is a critical constraint in health surveillance studies. Our optimized assay was successfully used to differentiate telomerase activity between unstimulated and stimulated cells, clearly showing the reactivation of telomerase upon cell activation. This assay is affordable, reproducible, and can be executed in resource-limited settings.


Subject(s)
Humans , Female , Pregnancy , Telomerase/genetics , Telomerase/metabolism , Neoplasms , Aging , Leukocytes, Mononuclear/metabolism , Chronic Disease , Cost-Benefit Analysis
4.
Braz. j. med. biol. res ; 54(11): e11352, 2021. tab, graf
Article in English | LILACS | ID: biblio-1339450

ABSTRACT

Diabetes mellitus is associated with neural and micro- and macrovascular complications. Therapeutic options for these complications are limited and the delivery of mesenchymal stem cells into lesions have been reported to improve the healing process. In this work, the effects of the administration of a lineage of human bone marrow mesenchymal stem cells immortalized by the expression of telomerase (hBMSC-TERT) as a potential therapeutic tool for wound healing in diabetic rats were investigated. This is the first description of the use of these cells in diabetic wounds. Dorsal cutaneous lesions were made in streptozotocin-induced diabetic rats and hBMSC-TERT were subcutaneously administered around the lesions. The healing process was evaluated macroscopically, histologically, and by birefringence analysis. Diabetic wounded rats infused with hBMSC-TERT (DM-TERT group) and the non-diabetic wounded rats not infused with hBMSC-TERT (CW group) had very similar patterns of fibroblastic response and collagen proliferation indicating improvement of wound healing. The result obtained by birefringence analysis was in accordance with that obtained by the histological analysis. The results indicated that local administration of hBMSC-TERT in diabetic wounds improved the wound healing process and may become a therapeutic option for wounds in individuals with diabetes.


Subject(s)
Humans , Animals , Rats , Telomerase , Diabetes Mellitus, Experimental , Mesenchymal Stem Cells , Wound Healing , Streptozocin
5.
Homeopatia Méx ; 89(720): 12-17, ene.-mar. 2020.
Article in Spanish | LILACS, HomeoIndex | ID: biblio-1147377

ABSTRACT

El proceso de envejecimiento se produce por la disminución de las funciones fisiológicas y de la capacidad de adaptación del organismo, siendo influenciado por la genética y el estilo de vida. Actualmente, con los avances de la genética, el envejecimiento biológico se puede calcular por la longitud de los telómeros ('telomere lenght'). Los telómeros son regiones en los extremos de los cromosomas que juegan un papel en el mantenimiento y la integridad del ADN. Con el envejecimiento biológico, se produce el acortamiento de los telómeros, causando la senescencia celular. Numerosos estudios evidencian que telómeros más cortos están asociados a enfermedades crónicas, a vicios y a intoxicaciones. Por otro lado, hábitos de vida saludables propician el aumento de la longitud de los telómeros y el equilibrio de las diversas funciones celulares, previniendo enfermedades. Por lo tanto, los telómeros funcionan como un biomarcador de la vitalidad del organismo.(AU)


Subject(s)
Aging , Chronic Disease , Telomere , Telomerase , Homeopathy
6.
Arch. endocrinol. metab. (Online) ; 63(2): 107-112, Mar.-Apr. 2019. tab, graf
Article in English | LILACS | ID: biblio-1001216

ABSTRACT

ABSTRACT Objectives: This observational study analyzed telomerase reverse transcriptase (pTERT) mutations in 45 fine-needle aspiration (FNA) specimens obtained from thyroid nodules followed by postoperatively confirmation of papillary thyroid cancer (PTC) diagnosis, examining their relationship with clinicopathologic aspects and the BRAFV600E mutation. Subjects and methods: Clinical information was collected from patients who presented to Ribeirao Preto University Hospital for surgical consultation regarding a thyroid nodule and who underwent molecular testing between January 2010 to October 2012. Tests included a DNA-based somatic detection of BRAFV600E and pTERT mutations. Results: We found coexistence of pTERTC228T and BRAFV600E mutations in 8.9% (4/45) of thyroid nodules. All nodules positive for pTERT mutations were BRAFV600E positives. There was a significant association between pTERTC228T/BRAFV600E with older age and advanced stage compared with the group negative for either mutation. Conclusions: This series provides evidence that FNA is a reliable method for preoperative diagnosis of high-risk thyroid nodules. pTERTC228T/BRAFV600E mutations could be a marker of poor prognosis. Its use as a personalized molecular medicine tool to individualize treatment decisions and follow-up design needs to be further studied.


Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Aged , Young Adult , Thyroid Neoplasms/genetics , Thyroid Nodule/genetics , Telomerase/genetics , Proto-Oncogene Proteins B-raf/genetics , Thyroid Cancer, Papillary/genetics , Prognosis , Thyroid Neoplasms/diagnosis , Thyroid Neoplasms/pathology , DNA Mutational Analysis , Predictive Value of Tests , Age Factors , Promoter Regions, Genetic/genetics , Thyroid Nodule/diagnosis , Thyroid Nodule/pathology , Biopsy, Fine-Needle , Preoperative Period , Thyroid Cancer, Papillary/diagnosis , Thyroid Cancer, Papillary/pathology , Lymphatic Metastasis/diagnosis , Mutation/genetics , Neoplasm Staging
8.
Article in Chinese | WPRIM | ID: wpr-774201

ABSTRACT

In recent years, the incidence of thyroid cancer has been increasing. Researchers around the world have begun to pay more attention to the exploration of its pathogenesis, disease evolution and prognosis. Among them, research in the field of gene molecules has become a hotspot, which includes the mutations of v-raf murine sarcoma viral oncogene homologue B1 (BRAF) and the telomerase reverse transcriptase (TERT) promoter. However, this field is not mature, and there are many problems and challenges need to be solved. This paper explores the value of BRAF mutation in the treatment, recurrence, mortality and prognosis of papillary thyroid carcinoma. In addition, we also explore the relationship between BRAF mutation and TERT promoter mutations and their influences in thyroid cancer. We hope this paper could help later scholars understand the current situation in this field and find a research direction in the future.


Subject(s)
Animals , Humans , Mutation , Promoter Regions, Genetic , Proto-Oncogene Proteins B-raf , Genetics , Telomerase , Genetics , Thyroid Neoplasms , Genetics
9.
Article in Chinese | WPRIM | ID: wpr-772705

ABSTRACT

OBJECTIVE@#This study aims to establish an effective and stable periodontal ligament cell line stably expressing human telomerase reverse transcriptase (hTERT) gene by using the adenovirus method.@*METHODS@#Polymerase chain reaction (PCR) was used to amplify the full length of hTERT gene to construct recombinant adenovirus plasmid pAd-pshuttle-cmv-hTERT. Packaged adenovirus particles were used for infection of human periodontal ligament cells. The expression levels of hTERT and osteogenic genes, such as alkaline phosphatase, Runt-related transcription factor 2, bone sialoprotein, osteocalcin, osteopontin, and collagen Ⅰ mRNA, were detected by quantitative real-time PCR (qRT-PCR). The ability of osteogenic differentiation was observed by alizarin red staining, and the cell proliferation was determined by CCK-8.@*RESULTS@#Adenovirus particles containing the hTERT gene were successfully constructed and infected with periodontal ligament cells. The infected cells were similar to normal periodontal ligament cells. The qRT-PCR results showed that hTERT and osteogenesis-associated genes were highly expressed in the periodontal ligament cell lines constructed by adenoviruses. Alizarin red staining showed that the periodontal ligament cell line had strong osteogenic differentiation capability. CCK-8 showed that the periodontal ligament cell line had strong proliferation capability.@*CONCLUSIONS@#The human periodontal ligament cell line with high efficiency and stable expression of hTERT was established by the adenovirus method, thereby providing an ideal cell line for studying the mechanism of periodontal regeneration.


Subject(s)
Adenoviridae , Alkaline Phosphatase , Cell Differentiation , Cell Line , Cell Proliferation , Humans , Osteogenesis , Periodontal Ligament , Telomerase
10.
Article in English | WPRIM | ID: wpr-741693

ABSTRACT

BACKGROUND/OBJECTIVES: Telomeres are located at the chromosomal ends and progressively shortened during each cell cycle. Telomerase, which is regulated by hTERT and c-MYC, maintains telomeric DNA sequences. Especially, telomerase is active in cancer and stem cells to maintain telomere length for replicative immortality. Recently we reported that walnut phenolic extract (WPE) can reduce cell viability in a colon cancer stem cell (CSC) model. We, therefore, investigated the effect of WPE on telomere maintenance in the same model. MATERIALS/METHODS: CD133+CD44+ cells from HCT116, a human colon cancer cell line, were sorted by Fluorescence-activated cell sorting (FACS) and treated with WPE at the concentrations of 0, 10, 20, and 40 µg/mL for 6 days. Telomere lengths were assessed by quantitative real-time PCR (qRT-PCR) using telomere specific primers and DNA extracted from the cells, which was further adjusted with single-copy gene and reference DNA (ddCt ). Telomerase activity was also measured by qRT-PCR after incubating the PCR mixture with cell protein extracts, which was adjusted with reference DNA (dCt ). Transcriptions of hTERT and c-MYC were determined using conventional RT-PCR. RESULTS: Telomere length of WPE-treated cells was significantly decreased in a dose-dependent manner (5.16 ± 0.13 at 0 µg/mL, 4.79 ± 0.12 at 10 µg/mL, 3.24 ± 0.08 at 20 µg/mL and 3.99 ± 0.09 at 40 µg/mL; P = 0.0276). Telomerase activities concurrently decreased with telomere length (1.47 ± 0.04, 1.09 ± 0.01, 0.76 ± 0.08, and 0.88 ± 0.06; P = 0.0067). There was a positive correlation between telomere length and telomerase activity (r = 0.9090; P < 0.0001). Transcriptions of both hTERT and c-MYC were also significantly decreased in the same manner. CONCLUSIONS: In the present cell culture model, WPE reduced telomere maintenance, which may provide a mechanistic link to the effect of walnuts on the viability of colon CSCs.


Subject(s)
Base Sequence , Cell Culture Techniques , Cell Cycle , Cell Line , Cell Survival , Colon , Colonic Neoplasms , DNA , Flow Cytometry , Humans , Juglans , Phenol , Polymerase Chain Reaction , Real-Time Polymerase Chain Reaction , Stem Cells , Telomerase , Telomere
11.
Article in English | WPRIM | ID: wpr-761902

ABSTRACT

BACKGROUND: This study aimed to observe the cartilaginous matrix production in SRY (sex determining region Y)-box 9 (SOX9)- and/or telomerase reverse transcriptase (TERT)-transfected chondrocytes from monolayer to three-dimensional (3D) culture.


Subject(s)
Alcian Blue , Cartilage , Chondrocytes , Clothing , Coloring Agents , Eosine Yellowish-(YS) , In Vitro Techniques , Proteoglycans , Real-Time Polymerase Chain Reaction , Regeneration , Telomerase , Tissue Engineering , Transfection
12.
Gut and Liver ; : 11-15, 2019.
Article in English | WPRIM | ID: wpr-719259

ABSTRACT

Previous studies have established a correlation between increasing chronological age and risk of cirrhosis. This pattern raised interest in the role of telomeres and the telomerase complex in the pathogenesis of liver fibrosis and cirrhosis. This review aims to summarize and analyze the current understanding of telomere regulation in hepatocytes and lymphocytes and how this ultimately relates to the development of liver fibrosis. Notably, in chronic viral hepatitis, telomere shortening in hepatocytes and lymphocytes occurs in such a way that may promote further viral replication while also leading to liver damage. However, while telomere shortening occurs in both hepatocytes and lymphocytes and ultimately results in cellular death, the mechanisms of telomere loss appear to be initiated by independent processes. The understanding of telomere maintenance on a hepatic and immune system level in both viral and non-viral etiologies of cirrhosis may open doors to novel therapeutic strategies.


Subject(s)
Fibrosis , Hepatitis , Hepatocytes , Immune System , Liver Cirrhosis , Liver Diseases , Liver , Lymphocytes , Telomerase , Telomere Shortening , Telomere
13.
Article in English | WPRIM | ID: wpr-739224

ABSTRACT

The development of next generation sequencing (NGS) has led to marked advancement of our understanding of genetic events mediating the initiation and progression of thyroid cancers. The NGS studies have confirmed the previously reported high frequency of mutually-exclusive oncogenic alterations affecting BRAF and RAS proto-oncogenes in all stages of thyroid cancer. Initially identified by traditional sequencing approaches, the NGS studies also confirmed the acquisition of alterations that inactivate tumor protein p53 (TP53) and activate phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) in advanced thyroid cancers. Novel alterations, such as those in telomerase reverse transcriptase (TERT) promoter and mating-type switching/sucrose non-fermenting (SWI/SNF) complex, are also likely to promote progression of the BRAF(V600E)-driven thyroid cancers. A number of genetically engineered mouse models (GEMM) of BRAF(V600E)-driven thyroid cancer have been developed to investigate thyroid tumorigenesis mediated by oncogenic BRAF and to explore the role of genetic alterations identified in the genomic analyses of advanced thyroid cancer to promote tumor progression. This review will discuss the various GEMMs that have been developed to investigate oncogenic BRAF(V600E)-driven thyroid cancers.


Subject(s)
Animals , Carcinogenesis , Catalytic Domain , Mice , Mice, Transgenic , Negotiating , Proto-Oncogene Proteins B-raf , Proto-Oncogenes , Telomerase , Thyroid Gland , Thyroid Neoplasms
14.
Article | WPRIM | ID: wpr-763558

ABSTRACT

Major psychiatric disorders are linked to early mortality and patients afflicted with these ailments demonstrate an increased risk of developing physical diseases that are characteristically seen in the elderly. Psychiatric conditions like major depressive disorder, bipolar disorder and schizophrenia may be associated with accelerated cellular aging, indicated by shortened leukocyte telomere length (LTL), which could underlie this connection. Telomere shortening occurs with repeated cell division and is reflective of a cell’s mitotic history. It is also influenced by cumulative exposure to inflammation and oxidative stress as well as the availability of telomerase, the telomere-lengthening enzyme. Precariously short telomeres can cause cells to undergo senescence, apoptosis or genomic instability; shorter LTL correlates with compromised general health and foretells mortality. Important data specify that LTL may be reduced in principal psychiatric illnesses, possibly in proportion to exposure to the ailment. Telomerase, as measured in peripheral blood monocytes, has been less well characterized in psychiatric illnesses, but a role in mood disorder has been suggested by preclinical and clinical studies. In this manuscript, the most recent studies on LTL and telomerase activity in mood disorders are comprehensively reviewed, potential mediators are discussed, and future directions are suggested. An enhanced comprehension of cellular aging in psychiatric illnesses could lead to their re-conceptualizing as systemic ailments with manifestations both inside and outside the brain. At the same time this paradigm shift could identify new treatment targets, helpful in bringing about lasting cures to innumerable sufferers across the globe.


Subject(s)
Aged , Aging , Apoptosis , Biology , Bipolar Disorder , Brain , Cellular Senescence , Cell Division , Comprehension , Depressive Disorder, Major , Genomic Instability , Humans , Inflammation , Leukocytes , Monocytes , Mood Disorders , Mortality , Oxidative Stress , Schizophrenia , Telomerase , Telomere Shortening , Telomere
15.
Rev. bras. psiquiatr ; 40(1): 19-25, Jan.-Mar. 2018. tab, graf
Article in English | LILACS | ID: biblio-899400

ABSTRACT

Objective: The findings of telomere length (TL) studies in bipolar disorder (BD) are controversial. The aim of the present study was to detect TL, human telomerase reverse transcriptase (hTERT), and brain derived neurotrophic factor (BDNF) in severe mania and subsequent remission. Methods: Twenty-one medication-free male patients and 20 age and gender matched controls were recruited. The patients were followed in the inpatient clinic, and comparisons were made between the same patients in their remission state and controls. Patients received lithium plus antipsychotics during the follow-up period. Quantitative real-time polymerase chain reaction was performed to verify leukocyte TL and whole blood hTERT gene expression levels. Serum BDNF levels were verified by enzyme-linked immunosorbent assay (ELISA). Results: Compared to controls, manic patients presented shorter telomeres (p < 0.001) whose length increased with treatment (p = 0.001). Patients in the late stages showed shorter TL than those in the early stages and controls (p < 0.001). hTERT gene expression levels were up-regulated in mania and remission compared to controls (p = 0.03 and p = 0.01, respectively). BDNF changes did not reach statistically significant levels. Conclusions: TL and hTERT gene expression might reflect a novel aspect of BD pathophysiology and TL might represent a novel biomarker for BD staging.


Subject(s)
Humans , Male , Adult , Bipolar Disorder/diagnosis , Telomere/genetics , Telomerase/genetics , Bipolar Disorder/genetics , Genetic Markers , Case-Control Studies , Real-Time Polymerase Chain Reaction , Telomere Shortening/genetics
16.
IBJ-Iranian Biomedical Journal. 2018; 22 (3): 171-179
in English | IMEMR | ID: emr-192466

ABSTRACT

Background: Curcumin, extracted from turmeric, represents enormous potential to serve as an anticancer agent. Telomerase is viewed as a prominent molecular target of curcumin, and transforming growth factor- beta 1 [TGF beta 1] has proven to be a major inhibitory signaling pathway for telomerase activity. In the current study, we aimed to explore suppressive effects of nanocurcumin on telomerase expression through TGF beta 1 pathway in a hepatocellular carcinoma cell line [Huh7]


Methods: MTT assay was used to determine the effect of nonocurcumin on viability of Huh7 cells. RT-PCR was used to analyze the gene expression patterns


Results: MTT assay revealed that nanocurcumin acts in a dose- and time-dependent manner to diminish the cell viability. RT-PCR analysis indicated that nanocurcumin results in augmentation of TGF beta 1 72 hours post treatment and leads to the reduction of telomerase expression 48 and 72 hours post exposure. Also, up-regulation of Smad3 and E2F1 and down-regulation of Smad7 confirmed the effect of nanocurcumin on intermediate components of TGF beta 1 pathway. Furthermore, transfection of the proximal promoter of telomerase triggered a significant reduction in luciferase activity


Conclusion: The data from the present study lead us to develop a deeper understanding of the mechanisms underlying nanocurcumin-mediated regulation of telomerase expression, thereby presenting a new perspective to the landscape of using nanocurcumin as a cancer-oriented therapeutic agent


Subject(s)
Animals, Laboratory , Liver Neoplasms/therapy , Liver Neoplasms/genetics , Curcumin/therapeutic use , Telomerase , Gene Expression , Transforming Growth Factor beta1
17.
Rev. chil. dermatol ; 34(2): 60-67, 2018. ilus, tab
Article in Spanish | LILACS | ID: biblio-994875

ABSTRACT

En la última década se ha avanzado en la caracterización genética y mapeo molecular del melanoma cutáneo con el objetivo de identificar y comprender mejor los mecanismos patogénicos propios de cada subgrupo y así desarrollar tratamientos específicos. El melanoma lentiginoso acral (MLA) constituye un subtipo de melanoma con características clínicas, epidemiológicas, histopatológicas, pronósticas y terapéuticas distintivas y su perfil mutacional no es la excepción. A diferencia del melanoma ubicado en zonas fotoexpuestas, el MLA presenta una baja tasa de mutaciones BRAF (15%) y mayor frecuencia de amplificaciones y ganancias genéticas de KIT (15-30%), CCND1 (15-40%) y TERT (20%). En esta revisión se describen las características más relevantes del MLA con énfasis en el rol que cumplen los principales genes que participan en la patogenia del MLA.


Over the last decade, the genetic characterization and molecular mapping of cutaneous melanoma has been developed in order to identify and better understand the pathogenic mechanisms of each subgroup and to develop specific treatments. Acral lentiginous melanoma (ALM) is a melanoma subtype with distinctive clinical, epidemiological, histopathological, prognostic and therapeutic features and its mutational profile is not an exception. Unlike melanoma located in photoexposed areas, MLA has a low rate of BRAF mutations (15%) and a higher frequency of amplifications and genetic gains at KIT (15-30%), CCND1 (15-40%) and TERT (20%). In this review we will describe the most relevant characteristics of MLA with emphasis on the role of the main genes involved in its pathogenesis.


Subject(s)
Humans , Skin Neoplasms/genetics , Melanoma/genetics , Prognosis , Skin Neoplasms/pathology , Telomerase/genetics , Proto-Oncogene Proteins c-kit/genetics , Cyclin D1/genetics , Melanoma/pathology , Mutation
18.
Journal of Breast Cancer ; : 391-398, 2018.
Article in English | WPRIM | ID: wpr-718894

ABSTRACT

PURPOSE: The aim of this study was to investigate the association of telomere length with breast cancer risk. We simultaneously explored the association between telomerase reverse transcriptase gene polymorphisms and telomere length. METHODS: We used real-time quantitative polymerase chain reaction to measure relative telomere length (RTL) in genomic DNA extracted from peripheral blood from 183 breast cancer cases and 191 healthy controls. Genotyping was performed using the Sequenom MassARRAY platform. RESULTS: Our results show that breast cancer patients had significantly shorter RTLs than control subjects (p 40 years (OR, 2.41; 95% CI, 1.31–4.43; p=0.005), body mass index ≤24 kg/m2 (OR, 2.81; 95% CI, 1.55–5.10; p=0.001), and postmenopausal women (OR, 3.94; 95% CI, 1.63–9.51; p=0.002), respectively. In addition, individuals with the AA genotype of rs2853677 have longer telomeres than those of breast cancer patients with the AG genotype (p=0.011). CONCLUSION: Our results suggest that shorter RTL was associated with an increased risk of breast cancer. An association was found between the AA genotype of rs2853677 and longer RTLs in the case group. Functional studies are warranted to validate this association and further investigate our findings.


Subject(s)
Asian Continental Ancestry Group , Body Mass Index , Breast Neoplasms , Breast , Case-Control Studies , DNA , Female , Genotype , Humans , Polymerase Chain Reaction , Real-Time Polymerase Chain Reaction , Telomerase , Telomere
19.
Article in English | WPRIM | ID: wpr-718790

ABSTRACT

BACKGROUND: Bone tissue engineering based on pluripotent stem cells (PSCs) is a new approach to deal with bone defects. Protocols have been developed to generate osteoblasts from PSCs. However, the low efficiency of this process is still an important issue that needs to be resolved. Many studies have aimed to improve efficiency, but developing accurate methods to determine efficacy is also critical. Studies using pluripotency to estimate efficacy are rare. Telomerase is highly associated with pluripotency. METHODS: We have described a quantitative method to measure telomerase activity, telomeric repeat elongation assay based on quartz crystal microbalance (QCM). To investigate whether this method could be used to determine the efficiency of in vitro osteogenic differentiation based on pluripotency, we measured the pluripotency pattern of cultures through stemness gene expression, proliferation ability and telomerase activity, measured by QCM. RESULTS: We showed that the pluripotency pattern determined by QCM was similar to the patterns of proliferation ability and gene expression, which showed a slight upregulation at the late stages, within the context of the general downregulation tendency during differentiation. Additionally, a comprehensive gene expression pattern covering nearly every stage of differentiation was identified. CONCLUSION: Therefore, this assay may be powerful tools for determining the efficiency of differentiation systems based on pluripotency. In this study, we not only introduce a new method for determining efficiency based on pluripotency, but also provide more information about the characteristics of osteogenic differentiation which help facilitate future development of more efficient protocols.


Subject(s)
Bone and Bones , Down-Regulation , Gene Expression , In Vitro Techniques , Methods , Mouse Embryonic Stem Cells , Osteoblasts , Pluripotent Stem Cells , Quartz Crystal Microbalance Techniques , Telomerase , Up-Regulation
20.
Article in English | WPRIM | ID: wpr-714223

ABSTRACT

PURPOSE: In this study, anaplastic lymphoma kinase (ALK) mutation and amplification, ALK protein expression, loss of the nuclear alpha thalassemia/mental retardation syndrome X-linked (ATRX) protein, and telomerase reverse transcriptase (TERT) protein expressionwere studied to investigate potential correlations between these molecular characteristics and clinical features or outcomes in neuroblastoma. MATERIALS AND METHODS: Seventy-two patients were enrolled in this study. Polymerase chain reaction amplification and direct sequencing were used for mutation analysis. ALK and MYCN amplifications were detected by fluorescence in situ hybridization. Protein expressionwas evaluated by immunohistochemical (IHC) staining. RESULTS: ALK mutation was found in only two patients (4.1%); ALK amplification was not detected. ALK positivity, loss of nuclear ATRX protein, TERT positivity by IHC were detected in 40 (55.6%), nine (13.0%), and 42 (59.2%) patients, respectively. The incidence of ALK expression increased in accordance with increasing tumor stage (p=0.001) and risk group (p < 0.001). The relapse rate was significantly higher in ALK+ patients compared to that of other patients (47.5% vs. 11.3%, p=0.007). However, there was no significant difference in relapse rate when the survival analysis was confined to the high-risk patients. CONCLUSION: Although ALK mutation was rare and no amplification was observed, ALK protein expression was found in a significant number of patients and was correlated with advanced stage and high-risk neuroblastoma. ALK protein expression could be considered as a marker related to the aggressive neuroblastoma, but it was not the independent prognostic factor for the outcome.


Subject(s)
Fluorescence , Humans , Immunohistochemistry , In Situ Hybridization , Incidence , Lymphoma , Neuroblastoma , Phosphotransferases , Polymerase Chain Reaction , Recurrence , Telomerase , Telomere
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