PAZ Y MIÑO CEPEDA, CÉSAR ANTONIO

Preferred name

Main Affiliation

Facultad de Ciencias de la Salud Eugenio Espejo

ORCID

0000-0002-6693-7344

Scopus Author ID

57196263036

Now showing 1 - 10 of 49

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Rare pathology derived from a ring chromosome 15. Clinical, genomic and protein interactome of genes associated with the phenotype
(Clinical Biotec, 2022-02-15)
PAZ Y MIÑO CEPEDA, CESAR ANTONIO
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Camila Medranda
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Alejandra Loaiza
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Mishell Ponce
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Paola E. Leone
<jats:p>The case of a 4-year-two-month-old female patient is presented, who consulted for a special phenotype: psychomotor retardation, short stature, microcephaly, large and low-set ears, small forehead, prominent brow ridges, labial commissure open, ocular hypertelorism, short neck, mammary hypertelorism and pectus excavatum. The objective of this study is to analyze a patient with unusual phenotypic traits, through physical examination, comparative analysis with other cases, and genetic studies. The cytogenetic study revealed a mosaic karyotype, mos 46,XX,r(15)(q26.3)/46,XX with the presence of the ring in 83%. The genetic mapping array study identified the loss of 3.5 Mb in 15q26.3. Among the genes lost in the terminal region of 15q, an interaction between their protein products was evidenced according to the STRING analysis. This is the second case of a ring chromosome 15 reported in Ecuador. And it would be the 101st in the world since 1966. The special phenotype of these individuals is related to the amount of genetic material lost. The genes involved in the formation of the ring, as well as the proteins that determine these genes and the relationships in different cellular pathways, are analyzed in silico in order to understand the pathophysiology of this disorder. Its diagnosis is mostly postnatal, so the clinical approach differs individually according to the symptoms and signs that appear.</jats:p>
Scopus© Citations 1
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Multi‐institutional experience of genetic diagnosis in Ecuador: National registry of chromosome alterations and polymorphisms
(Wiley, 2019-12-12)
PAZ Y MIÑO CEPEDA, CESAR ANTONIO
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Verónica Yumiceba
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Germania Moreta
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Rosario Paredes
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Mónica Ruiz
<jats:title>Abstract</jats:title><jats:sec><jats:title>Background</jats:title><jats:p>Detection of chromosomal abnormalities is crucial in various medical areas; to diagnose birth defects, genetic disorders, and infertility, among other complex phenotypes, in individuals across a wide range of ages. Hence, the present study wants to contribute to the knowledge of type and frequency of chromosomal alterations and polymorphisms in Ecuador.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>Cytogenetic registers from different Ecuadorian provinces have been merged and analyzed to construct an open‐access national registry of chromosome alterations and polymorphisms.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>Of 28,806 karyotypes analyzed, 6,008 (20.9%) exhibited alterations. Down syndrome was the most frequent autosome alteration (88.28%), followed by Turner syndrome (60.50%), a gonosome aneuploidy. A recurrent high percentage of Down syndrome mosaicism (7.45%) reported here, as well as by previous Ecuadorian preliminary registries, could be associated with geographic location and admixed ancestral composition. Translocations (2.46%) and polymorphisms (7.84%) were not as numerous as autosomopathies (64.33%) and gonosomopathies (25.37%). Complementary to conventional cytogenetics tests, molecular tools have allowed identification of submicroscopic alterations regions or candidate genes which can be possibly implicated in patients' symptoms and phenotypes.</jats:p></jats:sec><jats:sec><jats:title>Conclusion</jats:title><jats:p>The Ecuadorian National Registry of Chromosome Alterations and Polymorphisms provides a baseline to better understand chromosomal abnormalities in Ecuador and therefore their clinical management and awareness. This data will guide public policy makers to promote and financially support cytogenetic and genetic testing.</jats:p></jats:sec>
Scopus© Citations 4
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Genetic characterization of 12 STRs (Investigator® HDplex kit) in the Ecuadorian population
(Elsevier BV, 2019-12)
Aníbal Gaviria
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Gisella Fiallos
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Cristina Rodríguez-Pólit
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Lissett Boada
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Margarita Vela
Scopus© Citations 1
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Molecular variants associated with flavor perceptions and ancestral proportions of Ecuadorian populations
(Elsevier BV, 2019-12)
PAZ Y MIÑO CEPEDA, CESAR ANTONIO
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J.M. García-Cárdenas
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M.E. Dávalos
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A.C. Cárdenas Figueroa
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I. Armendáriz-Castillo
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A deep analysis using panel-based next-generation sequencing in an Ecuadorian pediatric patient with anaplastic astrocytoma: a case report
(Springer Science and Business Media LLC, 2020-08-31)
Jennyfer M. García-Cárdenas
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ZAMBRANO ESPINOSA, ANA KARINA
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Gabriel Runruil
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GUEVARA RAMIREZ, ALEXANDRA PATRICIA
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Santiago Guerrero
<jats:title>Abstract</jats:title><jats:sec><jats:title>Background</jats:title><jats:p>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.</jats:p></jats:sec><jats:sec><jats:title>Case presentation</jats:title><jats:p>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<jats:italic>FANCD2</jats:italic>,<jats:italic>NF1</jats:italic>,<jats:italic>FANCA</jats:italic>,<jats:italic>FANCI</jats:italic>, and<jats:italic>WRN.</jats:italic>Even though<jats:italic>TP53</jats:italic>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,<jats:italic>in silico</jats:italic>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.</jats:p></jats:sec><jats:sec><jats:title>Conclusions</jats:title><jats:p>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.</jats:p></jats:sec>
Scopus© Citations 2
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Genotoxic and Carcinogenic Potential of Compounds Associated with Electronic Cigarettes: A Systematic Review
(Hindawi Limited, 2019-12-23)
Isaac Armendáriz-Castillo
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Santiago Guerrero
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Antonella Vera-Guapi
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Tiffany Cevallos-Vilatuña
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Jennyfer M. García-Cárdenas
<jats:p><jats:italic>Background.</jats:italic> Many studies, comparing the health associated risks of electronic cigarettes with conventional cigarettes focus mainly on the common chemical compounds found between them. <jats:italic>Aim.</jats:italic> 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. <jats:italic>Data Sources.</jats:italic> Literature search was carried out using PubMed. <jats:italic>Study Eligibility Criteria.</jats:italic> 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. <jats:italic>Methods and Results.</jats:italic> 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. <jats:italic>Limitations.</jats:italic> Articles reporting conflicts of interest. <jats:italic>Conclusions and Implications of Key Findings.</jats:italic> 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.</jats:p>
Scopus© Citations 20
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Clinical, cytogenetic, and molecular findings in a patient with ring chromosome 4: case report and literature review
(Springer Science and Business Media LLC, 2019-11-21)
PAZ Y MIÑO CEPEDA, CESAR ANTONIO
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Ana Proaño
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Stella D. Verdezoto
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Juan Luis García
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Jesús María Hernández-Rivas
<jats:title>Abstract</jats:title><jats:sec> <jats:title>Background</jats:title> <jats:p>Since 1969, 49 cases have been presented on ring chromosome 4. All of these cases have been characterized for the loss of genetic material. The genes located in these chromosomal regions are related to the phenotype.</jats:p> </jats:sec><jats:sec> <jats:title>Case presentation</jats:title> <jats:p>A 10-year-old Ecuadorian Mestizo girl with ring chromosome 4 was clinically, cytogenetically and molecularly analysed. Clinical examination revealed congenital anomalies, including microcephaly, prominent nose, micrognathia, low set ears, bilateral clinodactyly of the fifth finger, small sacrococcygeal dimple, short stature and mental retardation. Cytogenetic studies showed a mosaic karyotype, mos 46,XX,r(4)(p16.3q35.2)/46,XX, with a ring chromosome 4 from 75 to 79% in three studies conducted over ten years. These results were confirmed by fluorescence in situ hybridization (FISH). Loss of 1.7 Mb and gain of 342 kb in 4p16.3 and loss of 3 Mb in 4q35.2 were identified by high-resolution mapping array.</jats:p> </jats:sec><jats:sec> <jats:title>Conclusion</jats:title> <jats:p>Most cases with ring chromosome 4 have deletion of genetic material in terminal regions; however, our case has inv dup del rearrangement in the ring chromosome formation. Heterogeneous clinical features in all cases reviewed are related to the amount of genetic material lost or gained. The application of several techniques can increase our knowledge of ring chromosome 4 and its deviations from typical “ring syndrome.”</jats:p> </jats:sec>
Scopus© Citations 2
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Oncology and Pharmacogenomics Insights in Polycystic Ovary Syndrome: An Integrative Analysis
(Frontiers Media SA, 2020-10-26)
Verónica Yumiceba
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Andrés López-Cortés
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Andy Pérez-Villa
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Iván Yumiseba
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Santiago Guerrero
<jats:p>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.<jats:italic>PTEN</jats:italic>had the highest number of mutations in EC,<jats:italic>TP53</jats:italic>, in OC, and<jats:italic>FSHR</jats:italic>, 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,<jats:italic>in silico</jats:italic>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.</jats:p>
Scopus© Citations 33
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Consensus strategy in genes prioritization and combined bioinformatics analysis for preeclampsia pathogenesis
(Springer Science and Business Media LLC, 2017-08-08)
Eduardo Tejera
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Maykel Cruz-Monteagudo
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Germán Burgos
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María-Eugenia Sánchez
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Aminael Sánchez-Rodríguez
Scopus© Citations 22
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Mutational Analysis of Oncogenic AKT1 Gene Associated with Breast Cancer Risk in the High Altitude Ecuadorian Mestizo Population
(Hindawi Limited, 2018-07-03)
Andrés López-Cortés
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Paola E. Leone
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Byron Freire-Paspuel
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Nathaly Arcos-Villacís
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GUEVARA RAMIREZ, ALEXANDRA PATRICIA
<jats:p>Breast cancer is the leading cause of cancer-related death among women worldwide. AKT1 encodes the kinase B alpha protein. The rs121434592, rs12881616, rs11555432, rs11555431, rs2494732, and rs3803304 single nucleotide polymorphisms have been identified in the AKT1 kinase gene. Activated AKT1 phosphorylates downstream substrates regulating cell growth, metabolism, apoptosis, angiogenesis, and drug responses. It is essential to know how breast cancer risk is associated with histopathological and immunohistochemical characteristics and genotype polymorphisms in a high altitude Ecuadorian mestizo population. This is a retrospective case-control study. DNA was extracted from 185 healthy and 91 affected women who live 2,800 meters above sea level. Genotypes were determined by genomic sequencing. We found a possible association between the noncoding intronic variant rs3803304 and breast cancer risk development: GG (odds ratio [OR] = 5.2; 95% confidence interval [CI] = 1.3-20.9;<jats:italic> P</jats:italic> ≤ 0.05;<jats:italic> Q</jats:italic> > 0.05). Regarding pathologic characteristics, we found significant risk between estrogen receptor, progesterone receptor, and HER2 status and molecular subtypes (<jats:italic>P</jats:italic> ≤ 0.001;<jats:italic> Q</jats:italic> ≤ 0.05). On the other hand, we did not find risk between variants and histopathological characteristics. Despite the small sample size, we found that the intronic variant, AKT1 rs3803304, may act as a predictive biomarker in the risk of developing breast cancer in the high altitude Ecuadorian mestizo population.</jats:p>
Scopus© Citations 27

PAZ Y MIÑO CEPEDA, CÉSAR ANTONIO

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