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1.
Leukemia ; 37(1): 134-142, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36411356

RESUMEN

Acute myeloid leukemia (AML) is characterized by complex molecular alterations and driver mutations. Elderly patients show increased frequencies of IDH mutations with high chemoresistance and relapse rates despite recent therapeutic advances. Besides being associated with global promoter hypermethylation, IDH1 mutation facilitated changes in 3D DNA-conformation by CTCF-anchor methylation and upregulated oncogene expression in glioma, correlating with poor prognosis. Here, we investigated the role of IDH1 p.R132H mutation in altering 3D DNA-architecture and subsequent oncogene activation in AML. Using public RNA-Seq data, we identified upregulation of tyrosine kinase PDGFRA in IDH1-mutant patients, correlating with poor prognosis. DNA methylation analysis identified CpG hypermethylation within a CTCF-anchor upstream of PDGFRA in IDH1-mutant patients. Increased PDGFRA expression, PDGFRA-CTCF methylation and decreased CTCF binding were confirmed in AML CRISPR cells with heterozygous IDH1 p.R132H mutation and upon exogenous 2-HG treatment. IDH1-mutant cells showed higher sensitivity to tyrosine kinase inhibitor dasatinib, which was supported by reduced blast count in a patient with refractory IDH1-mutant AML after dasatinib treatment. Our data illustrate that IDH1 p.R132H mutation leads to CTCF hypermethylation, disrupting DNA-looping and insulation of PDGFRA, resulting in PDGFRA upregulation in IDH1-mutant AML. Treatment with dasatinib may offer a novel treatment strategy for IDH1-mutant AML.


Asunto(s)
Isocitrato Deshidrogenasa , Leucemia Mieloide Aguda , Humanos , Anciano , Isocitrato Deshidrogenasa/genética , Isocitrato Deshidrogenasa/metabolismo , Dasatinib , Mutación , Oncogenes , Leucemia Mieloide Aguda/genética , Carcinogénesis/genética
2.
Sci Rep ; 12(1): 11100, 2022 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-35773405

RESUMEN

Many primary-tumor subregions exhibit low levels of molecular oxygen and restricted access to nutrients due to poor vascularization in the tissue, phenomenon known as hypoxia. Hypoxic tumors are able to regulate the expression of certain genes and signaling molecules in the microenvironment that shift it towards a more aggressive phenotype. The transcriptional landscape of the tumor favors malignant transformation of neighboring cells and their migration to distant sites. Herein, we focused on identifying key proteins that participate in the signaling crossroads between hypoxic environment and metastasis progression that remain poorly defined. To shed light on these mechanisms, we performed an integrated multi-omics analysis encompassing genomic/transcriptomic alterations of hypoxia-related genes and Buffa hypoxia scores across 17 pancarcinomas taken from the PanCancer Atlas project from The Cancer Genome Atlas consortium, protein-protein interactome network, shortest paths from hypoxia-related proteins to metastatic and angiogenic phenotypes, and drugs involved in current clinical trials to treat the metastatic disease. As results, we identified 30 hypoxia-related proteins highly involved in metastasis and angiogenesis. This set of proteins, validated with the MSK-MET Project, could represent key targets for developing therapies. The upregulation of mRNA was the most prevalent alteration in all cancer types. The highest frequencies of genomic/transcriptomic alterations and hypoxia score belonged to tumor stage 4 and positive metastatic status in all pancarcinomas. The most significantly associated signaling pathways were HIF-1, PI3K-Akt, thyroid hormone, ErbB, FoxO, mTOR, insulin, MAPK, Ras, AMPK, and VEGF. The interactome network revealed high-confidence interactions among hypoxic and metastatic proteins. The analysis of shortest paths revealed several ways to spread metastasis and angiogenesis from hypoxic proteins. Lastly, we identified 23 drugs enrolled in clinical trials focused on metastatic disease treatment. Six of them were involved in advanced-stage clinical trials: aflibercept, bevacizumab, cetuximab, erlotinib, ipatasertib, and panitumumab.


Asunto(s)
Neoplasias , Fosfatidilinositol 3-Quinasas , Hipoxia de la Célula/genética , Línea Celular Tumoral , Humanos , Hipoxia/genética , Hipoxia/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Metástasis de la Neoplasia , Neoplasias/patología , Neovascularización Patológica/tratamiento farmacológico , Neovascularización Patológica/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Transducción de Señal , Microambiente Tumoral
3.
Front Endocrinol (Lausanne) ; 11: 585130, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33329391

RESUMEN

Polycystic ovary syndrome (PCOS) is a heterogeneous endocrine disorder characterized by hyperandrogenism, ovulatory dysfunction, and polycystic ovaries. Epidemiological findings revealed that women with PCOS are prone to develop certain cancer types due to their shared metabolic and endocrine abnormalities. However, the mechanism that relates PCOS and oncogenesis has not been addressed. Herein, in this review article the genomic status, transcriptional and protein profiles of 264 strongly PCOS related genes (PRG) were evaluated in endometrial cancer (EC), ovarian cancer (OV) and breast cancer (BC) exploring oncogenic databases. The genomic alterations of PRG were significantly higher when compared with a set of non-diseases genes in all cancer types. PTEN had the highest number of mutations in EC, TP53, in OC, and FSHR, in BC. Based on clinical data, women older than 50 years and Black or African American females carried the highest ratio of genomic alterations among all cancer types. The most altered signaling pathways were p53 in EC and OC, while Fc epsilon RI in BC. After evaluating PRG in normal and cancer tissue, downregulation of the differentially expressed genes was a common feature. Less than 30 proteins were up and downregulated in all cancer contexts. We identified 36 highly altered genes, among them 10 were shared between the three cancer types analyzed, which are involved in the cell proliferation regulation, response to hormone and to endogenous stimulus. Despite limited PCOS pharmacogenomics studies, 10 SNPs are reported to be associated with drug response. All were missense mutations, except for rs8111699, an intronic variant characterized as a regulatory element and presumably binding site for transcription factors. In conclusion, in silico analysis revealed key genes that might participate in PCOS and oncogenesis, which could aid in early cancer diagnosis. Pharmacogenomics efforts have implicated SNPs in drug response, yet still remain to be found.


Asunto(s)
Antineoplásicos/uso terapéutico , Biomarcadores de Tumor/genética , Mutación , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Farmacogenética , Síndrome del Ovario Poliquístico/fisiopatología , Femenino , Humanos , Neoplasias/patología
4.
J Med Case Rep ; 14(1): 136, 2020 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-32867815

RESUMEN

BACKGROUND: Anaplastic astrocytoma is a rare disorder in children from 10 to 14 years of age, with an estimated 0.38 new cases per 100,000 people per year worldwide. Panel-based next-generation sequencing opens new possibilities for diagnosis and therapy of rare diseases such as this one. Because it has never been genetically studied in the Ecuadorian population, we chose to genetically characterize an Ecuadorian pediatric patient with anaplastic astrocytoma for the first time. Doing so allows us to provide new insights into anaplastic astrocytoma diagnosis and treatment. CASE PRESENTATION: Our patient was a 13-year-old Mestizo girl with an extensive family history of cancer who was diagnosed with anaplastic astrocytoma. According to ClinVar, SIFT, and PolyPhen, the patient harbored 354 genomic alterations in 100 genes. These variants were mostly implicated in deoxyribonucleic acid (DNA) repair. The top five most altered genes were FANCD2, NF1, FANCA, FANCI, and WRN. Even though TP53 presented only five mutations, the rs11540652 single-nucleotide polymorphism classified as pathogenic was found in the patient and her relatives; interestingly, several reports have related it to Li-Fraumeni syndrome. Furthermore, in silico analysis using the Open Targets Platform revealed two clinical trials for pediatric anaplastic astrocytoma (studying cabozantinib, ribociclib, and everolimus) and 118 drugs that target the patient's variants, but the studies were not designed specifically to treat pediatric anaplastic astrocytoma. CONCLUSIONS: Next-generation sequencing allows genomic characterization of rare diseases; for instance, this study unraveled a pathogenic single-nucleotide polymorphism related to Li-Fraumeni syndrome and identified possible new drugs that specifically target the patient's variants. Molecular tools should be implemented in routine clinical practice for early detection and effective preemptive intervention delivery and treatment.


Asunto(s)
Astrocitoma , Glioblastoma , Síndrome de Li-Fraumeni , Adolescente , Astrocitoma/genética , Niño , Ecuador , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos
5.
BMC Med Genomics ; 13(1): 113, 2020 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-32807182

RESUMEN

BACKGROUND: Congenital insensitivity to pain with anhidrosis (CIPA) is an extremely rare autosomal recessive disorder characterized by insensitivity to pain, inability to sweat and intellectual disability. CIPA is caused by mutations in the neurotrophic tyrosine kinase receptor type 1 gene (NTRK1) that encodes the high-affinity receptor of nerve growth factor (NGF). CASE PRESENTATION: Here, we present clinical and molecular findings in a 9-year-old girl with CIPA. The high-altitude indigenous Ecuadorian patient presented several health problems such as anhidrosis, bone fractures, self-mutilation, osteochondroma, intellectual disability and Riga-Fede disease. After the mutational analysis of NTRK1, the patient showed a clearly autosomal recessive inheritance pattern with the pathogenic mutation rs763758904 (Arg602*) and the second missense mutation rs80356677 (Asp674Tyr). Additionally, the genomic analysis showed 69 pathogenic and/or likely pathogenic variants in 46 genes possibly related to phenotypic heterogeneity, including the rs324420 variant in the FAAH gene. The gene ontology enrichment analysis showed 28 mutated genes involved in several biological processes. As a novel contribution, the protein-protein interaction network analysis showed that NTRK1, SPTBN2 and GRM6 interact with several proteins of the pain matrix involved in the response to stimulus and nervous system development. CONCLUSIONS: This is the first study that associates clinical, genomics and networking analyses in a Native American patient with consanguinity background in order to better understand CIPA pathogenesis.


Asunto(s)
Altitud , Marcadores Genéticos , Hipohidrosis/patología , Mutación , Insensibilidad Congénita al Dolor/patología , Dolor/patología , Niño , Análisis Mutacional de ADN , Femenino , Genómica , Humanos , Hipohidrosis/genética , Hipohidrosis/metabolismo , Dolor/genética , Dolor/metabolismo , Insensibilidad Congénita al Dolor/genética , Insensibilidad Congénita al Dolor/metabolismo , Mapas de Interacción de Proteínas
6.
Genes (Basel) ; 11(7)2020 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-32708340

RESUMEN

Telomere maintenance mechanisms (TMM) are used by cancer cells to avoid apoptosis, 85-90% reactivate telomerase, while 10-15% use the alternative lengthening of telomeres (ALT). Due to anti-telomerase-based treatments, some tumors switch from a telomerase-dependent mechanism to ALT; in fact, the co-existence between both mechanisms has been observed in some cancers. Although different elements in the ALT pathway are uncovered, some molecular mechanisms are still poorly understood. Therefore, with the aim to identify potential molecular markers for the study of ALT, we combined in silico approaches in a 411 telomere maintenance gene set. As a consequence, we conducted a genomic analysis of these genes in 31 Pan-Cancer Atlas studies from The Cancer Genome Atlas and found 325,936 genomic alterations; from which, we identified 20 genes highly mutated in the cancer studies. Finally, we made a protein-protein interaction network and enrichment analysis to observe the main pathways of these genes and discuss their role in ALT-related processes, like homologous recombination and homology directed repair. Overall, due to the lack of understanding of the molecular mechanisms of ALT cancers, we proposed a group of genes, which after ex vivo validations, could represent new potential therapeutic markers in the study of ALT.


Asunto(s)
Neoplasias/genética , Homeostasis del Telómero , Predisposición Genética a la Enfermedad , Humanos , Neoplasias/metabolismo , Mapas de Interacción de Proteínas , Proteínas de Unión a Telómeros/genética , Proteínas de Unión a Telómeros/metabolismo
7.
Biomed Res Int ; 2020: 9074760, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32596391

RESUMEN

The incidence of cystic fibrosis (CF) and the frequency of the variants reported for CFTR depend on the population; furthermore, CF symptomatology is characterized by obstructive lung disease and pancreatic insufficiency among other symptoms, which are reliant on the individual's genotype. The Ecuadorian population is a mixture of Native Americans, Europeans, and Africans. That population admixture could be the reason for the new mutations reported in a previous study by Ruiz et al. (2019). A panel of 46 Ancestry Informative Markers was used to estimate the ancestral proportions of each available sample (12 samples in total). As a result, the Native American ancestry proportion was the most prevalent in almost all individuals, except for three patients from Guayaquil with the mutation [c.757G>A:p.Gly253Arg; c.1352G>T:p.Gly451Val] who had the highest European composition.


Asunto(s)
Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Fibrosis Quística/genética , Mutación/genética , Ecuador , Genotipo , Humanos , Análisis de Componente Principal , Grupos Raciales/genética
8.
Front Mol Biosci ; 6: 65, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31440515

RESUMEN

Colorectal cancer (CRC) is a major health problem with an estimated 1. 8 million new cases worldwide. To date, most CRC studies have focused on DNA-related aberrations, leaving post-transcriptional processes under-studied. However, post-transcriptional alterations have been shown to play a significant part in the maintenance of cancer features. RNA binding proteins (RBPs) are uprising as critical regulators of every cancer hallmark, yet little is known regarding the underlying mechanisms and key downstream oncogenic targets. Currently, more than a thousand RBPs have been discovered in humans and only a few have been implicated in the carcinogenic process and even much less in CRC. Identification of cancer-related RBPs is of great interest to better understand CRC biology and potentially unveil new targets for cancer therapy and prognostic biomarkers. In this work, we reviewed all RBPs which have a role in CRC, including their control by microRNAs, xenograft studies and their clinical implications.

9.
Biomed Res Int ; 2019: 1386710, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31950030

RESUMEN

BACKGROUND: Many studies, comparing the health associated risks of electronic cigarettes with conventional cigarettes focus mainly on the common chemical compounds found between them. AIM: Review chemical compounds found exclusively in electronic cigarettes and describe their toxic effects, focusing on electronic-cigarette-only and dual electronic-cigarette and conventional cigarette users. DATA SOURCES: Literature search was carried out using PubMed. STUDY ELIGIBILITY CRITERIA: Articles related exclusively to conventional and electronic cigarettes' chemical composition. Articles which reported to be financed from tobacco or electronic cigarettes industries, not reporting source of funding, not related to the chemical composition of electronic and conventional cigarettes and not relevant to tobacco research were excluded. METHODS AND RESULTS: Chemical compounds reported in the selected studies were tabulated using the Chemical Abstracts Service registry number for chemical substances information. A total of 50 chemical compounds were exclusively reported to be present in electronic cigarettes. Crucial health risks identified were: eye, skin, and respiratory tract irritation, with almost 50% of incidence, an increment of 10% in cytotoxic effects, when compared to compounds in common with conventional cigarettes and around 11% of compounds with unknown effects to human health. LIMITATIONS: Articles reporting conflicts of interest. CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS: Despite being considered as less harmful for human health, compounds found in electronic cigarettes are still a matter of research and their effects on health are yet unknown. The use of these devices is not recommended for first time users and it is considered hazardous for dual users.


Asunto(s)
Carcinogénesis/efectos de los fármacos , Carcinógenos/toxicidad , Sistemas Electrónicos de Liberación de Nicotina , Mutágenos/toxicidad , Daño del ADN/efectos de los fármacos , Humanos , Nicotina/toxicidad , Cese del Hábito de Fumar , Productos de Tabaco/efectos adversos
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