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    Case Report: CYLD cutaneous syndrome with malignant transformation to spiradenocarcinoma: cooperative effects of CYLD truncation and an MSH2 clamp-domain variant in an Ecuadorian patient
    (Frontiers Media SA, 2026-02-18)
    Carlos Reyes-Silva
    ;
    Gabriela Jaramillo-Koupermann
    ;
    Maritza Quishpe
    ;
    Rosa Pacheco
    ;
    Skehirly Burgos-Tapia
    Background: CYLD cutaneous syndrome (CCS) is a rare autosomal dominant disorder caused by germline CYLD variants and characterized by multiple skin adnexal tumors. Malignant transformation is uncommon, and cooperative genetic events remain poorly defined, particularly in underrepresented populations. Case presentation: We report a 61-year-old Ecuadorian woman with multiple scalp cylindromas and spiradenomas, including one spiradenocarcinoma. Family history was notable for malignancies in first- and second-degree relatives. Whole-exome sequencing identified a heterozygous nonsense CYLD variant (c.1207C > T; p.Gln403Ter), classified as likely pathogenic, and a homozygous missense MSH2 variant (c.1609A > G; p.Lys537Glu) of uncertain significance. Histopathology confirmed malignant transformation, while immunohistochemistry showed preserved MSH2 expression with a microsatellite-stable phenotype. Nevertheless, a functional impact of the MSH2 variant cannot be excluded. Consistent with these observations, in silico modeling demonstrated that CYLD truncation eliminates the catalytic USP domain and regulatory motifs, abolishing deubiquitinase activity, whereas the MSH2 substitution affects a conserved residue in the clamp domain, likely destabilizing the MSH2–MSH6 complex despite intact nuclear localization. Conclusion: This is the first genetically confirmed case of CCS in Ecuador and among the few reported in South America. Beyond expanding the geographic spectrum, our findings highlight the value of integrating genomic and protein analyses to uncover cooperative mechanisms of malignant progression. Such integrative genomic approaches refine diagnosis, enhance genotype–phenotype interpretation, and deepen understanding of malignant transformation in CCS, particularly in underrepresented populations.
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    Gut Microbiota Disruption in Hematologic Cancer Therapy: Molecular Insights and Implications for Treatment Efficacy
    Hematologic malignancies (HMs), including leukemia, lymphoma, and multiple myeloma, involve the uncontrolled proliferation of abnormal blood cells, posing significant clinical challenges due to their heterogeneity and varied treatment responses. Despite recent advancements in therapies that have improved survival rates, particularly in chronic lymphocytic leukemia and acute lymphoblastic leukemia, treatments like chemotherapy and stem cell transplantation often disrupt gut microbiota, which can negatively impact treatment outcomes and increase infection risks. This review explores the complex, bidirectional interactions between gut microbiota and cancer treatments in patients with HMs. Gut microbiota can influence drug metabolism through mechanisms such as the production of enzymes like bacterial β-glucuronidases, which can alter drug efficacy and toxicity. Moreover, microbial metabolites like short-chain fatty acids can modulate the host immune response, enhancing treatment effectiveness. However, therapy often reduces the diversity of beneficial bacteria, such as Bifidobacterium and Faecalibacterium, while increasing pathogenic bacteria like Enterococcus and Escherichia coli. These findings highlight the critical need to preserve microbiota diversity during treatment. Future research should focus on personalized microbiome-based therapies, including probiotics, prebiotics, and fecal microbiota transplantation, to improve outcomes and quality of life for patients with hematologic malignancies.
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    Genotyping the High Altitude Mestizo Ecuadorian Population Affected with Prostate Cancer
    (Hindawi Limited, 2017)
    Andrés López-Cortés
    ;
    Alejandro Cabrera-Andrade
    ;
    Carolina Salazar-Ruales
    ;
    ;
    Santiago Guerrero
    <jats:p>Prostate cancer (PC) is the second most commonly diagnosed type of cancer in males with 1,114,072 new cases in 2015. The MTHFR enzyme acts in the folate metabolism, which is essential in methylation and synthesis of nucleic acids. MTHFR C677T alters homocysteine levels and folate assimilation associated with DNA damage. Androgens play essential roles in prostate growth. The SRD5A2 enzyme metabolizes testosterone and the V89L polymorphism reduces in vivo SRD5A2 activity. The androgen receptor gene codes for a three-domain protein that contains two polymorphic trinucleotide repeats (CAG, GGC). Therefore, it is essential to know how PC risk is associated with clinical features and polymorphisms in high altitude Ecuadorian mestizo populations. We analyzed 480 healthy and 326 affected men from our three retrospective case-control studies. We found significant association between MTHFR C/T (odds ratio [OR] = 2.2;<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M1"><mml:mi>P</mml:mi><mml:mo>=</mml:mo><mml:mn fontstyle="italic">0.009</mml:mn></mml:math>), MTHFR C/T+T/T (OR = 2.22;<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M2"><mml:mi>P</mml:mi><mml:mo>=</mml:mo><mml:mn fontstyle="italic">0.009</mml:mn></mml:math>), and PC. The SRD5A2 A49T substitution was associated with higher pTNM stage (OR = 2.88;<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M3"><mml:mi>P</mml:mi><mml:mo>=</mml:mo><mml:mn fontstyle="italic">0.039</mml:mn></mml:math>) and elevated Gleason grade (OR = 3.15;<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M4"><mml:mi>P</mml:mi><mml:mo>=</mml:mo><mml:mn fontstyle="italic">0.004</mml:mn></mml:math>). Additionally, patients with ≤21 CAG repeats have an increased risk of developing PC (OR = 2.99;<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M5"><mml:mi>P</mml:mi><mml:mo>&lt;</mml:mo><mml:mn fontstyle="italic">0.001</mml:mn></mml:math>). In conclusion, genotype polymorphism studies are important to characterize genetic variations in high altitude mestizo populations.</jats:p>
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    Item type:Publication,
    Salivary MicroRNAs for Early Detection of Head and Neck Squamous Cell Carcinoma: A Case-Control Study in the High Altitude Mestizo Ecuadorian Population
    (Hindawi Limited, 2018-11-21)
    Carolina Salazar-Ruales
    ;
    Jessica-Viviana Arguello
    ;
    Andrés López-Cortés
    ;
    Alejandro Cabrera-Andrade
    ;
    Jennyfer M. García-Cárdenas
    <jats:p>Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer with the highest incidence worldwide. HNSCC is often diagnosed at advanced stages, incurring significant high mortality and morbidity. The use of saliva, as a noninvasive tool for the diagnosis of cancer, has recently increased. Salivary microRNAs (miRNAs) have emerged as a promising molecular tool for early diagnosis of HNSCC. The aim was to identify the differential expression of salivary miRNAs associated with HNSCC in the high altitude mestizo Ecuadorian population. Using PCR Arrays, miR-122-5p, miR-92a-3p, miR-124-3p, miR-205-5p, and miR-146a-5p were found as the most representative ones. Subsequently, miRNAs expression was confirmed in saliva samples from 108 cases and 108 controls. miR-122-5p, miR-92a-3p, miR-124-3p, and miR-146a-5p showed significant statistical difference between cases and controls with areas under the curve (AUC) of 0.73 (p &lt; 0.001), 0.70 (p &lt; 0.001), 0.71 (p = 0.002), and 0.66 (p = 0.008), respectively. miRNAs were also deregulated in between HNSCC localizations. A differentiated expression of miR-122-5p between oral cancer and oropharynx cancer (AUC of 0.96 p = 0.01) was found: miR-124-3p between larynx and pharynx (AUC = 0.97, p &lt; 0.01) and miR-146a-5p between larynx, oropharynx, and oral cavity (AUC = 0.96, p = 0.01). Moreover, miR-122-5p, miR-124-3p, miR-205-5p, and miR-146a-5p could differentiate between HPV+ and HPV- (p=0.004). Finally, the expression profiles of the five miRNAs were evaluated to discriminate HNSCC patient’s tumor stages (TNM 2-4). miR-122-5p differentiates TNM 2 and 3 (p = 0.002, AUC = 0.92), miR-124-3p TNM 2, 3, and 4 (p &lt; 0.001, AUC = 98), miR-146a-5p TNM 2 and 3 (p &lt; 0.001, AUC = 0.97), and miR-92a-3p TNM 3 (p &lt; 0.001, AUC = 0.99). Taken together, these findings show that altered expression of miRNAs could be used as biomarkers for HNSCC diagnosis in the high altitude mestizo Ecuadorian population.</jats:p>
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    Item type:Publication,
    Breast Cancer Risk Associated with Genotype Polymorphisms of the Aurora Kinase a Gene (AURKA): a Case-Control Study in a High Altitude Ecuadorian Mestizo Population
    (Springer Science and Business Media LLC, 2017-06-24)
    Andrés López-Cortés
    ;
    Alejandro Cabrera-Andrade
    ;
    Fabián Oña-Cisneros
    ;
    Felipe Rosales
    ;
    Malena Ortiz
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    Item type:Publication,
    Erratum to: Breast Cancer Risk Associated with Genotype Polymorphisms of the Aurora Kinase a Gene (AURKA): a Case-Control Study in a High Altitude Ecuadorian Mestizo Population
    (Springer Science and Business Media LLC, 2017-09-05)
    Andrés López-Cortés
    ;
    Alejandro Cabrera-Andrade
    ;
    Fabián Oña-Cisneros
    ;
    Carolina Echeverría
    ;
    Felipe Rosales
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    Analysis of Racial/Ethnic Representation in Select Basic and Applied Cancer Research Studies
    (Springer Science and Business Media LLC, 2018-09-18)
    Santiago Guerrero
    ;
    Andrés López-Cortés
    ;
    Alberto Indacochea
    ;
    Jennyfer M. García-Cárdenas
    ;
    <jats:title>Abstract</jats:title><jats:p>Over the past decades, consistent studies have shown that race/ethnicity have a great impact on cancer incidence, survival, drug response, molecular pathways and epigenetics. Despite the influence of race/ethnicity in cancer outcomes and its impact in health care quality, a comprehensive understanding of racial/ethnic inclusion in oncological research has never been addressed. We therefore explored the racial/ethnic composition of samples/individuals included in fundamental (patient-derived oncological models, biobanks and genomics) and applied cancer research studies (clinical trials). Regarding patient-derived oncological models (n = 794), 48.3% have no records on their donor’s race/ethnicity, the rest were isolated from White (37.5%), Asian (10%), African American (3.8%) and Hispanic (0.4%) donors. Biobanks (n = 8,293) hold specimens from unknown (24.56%), White (59.03%), African American (11.05%), Asian (4.12%) and other individuals (1.24%). Genomic projects (n = 6,765,447) include samples from unknown (0.6%), White (91.1%), Asian (5.6%), African American (1.7%), Hispanic (0.5%) and other populations (0.5%). Concerning clinical trials (n = 89,212), no racial/ethnic registries were found in 66.95% of participants, and records were mainly obtained from Whites (25.94%), Asians (4.97%), African Americans (1.08%), Hispanics (0.16%) and other minorities (0.9%). Thus, two tendencies were observed across oncological studies: lack of racial/ethnic information and overrepresentation of Caucasian/White samples/individuals. These results clearly indicate a need to diversify oncological studies to other populations along with novel strategies to enhanced race/ethnicity data recording and reporting.</jats:p>
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    Gene prioritization, communality analysis, networking and metabolic integrated pathway to better understand breast cancer pathogenesis
    (Springer Science and Business Media LLC, 2018-11-12)
    Andrés López-Cortés
    ;
    ;
    Alejandro Cabrera-Andrade
    ;
    Stephen J. Barigye
    ;
    Cristian R. Munteanu
    <jats:title>Abstract</jats:title><jats:p>Consensus strategy was proved to be highly efficient in the recognition of gene-disease association. Therefore, the main objective of this study was to apply theoretical approaches to explore genes and communities directly involved in breast cancer (BC) pathogenesis. We evaluated the consensus between 8 prioritization strategies for the early recognition of pathogenic genes. A communality analysis in the protein-protein interaction (PPi) network of previously selected genes was enriched with gene ontology, metabolic pathways, as well as oncogenomics validation with the OncoPPi and DRIVE projects. The consensus genes were rationally filtered to 1842 genes. The communality analysis showed an enrichment of 14 communities specially connected with ERBB, PI3K-AKT, mTOR, FOXO, p53, HIF-1, VEGF, MAPK and prolactin signaling pathways. Genes with highest ranking were TP53, ESR1, BRCA2, BRCA1 and ERBB2. Genes with highest connectivity degree were TP53, AKT1, SRC, CREBBP and EP300. The connectivity degree allowed to establish a significant correlation between the OncoPPi network and our BC integrated network conformed by 51 genes and 62 PPi. In addition, CCND1, RAD51, CDC42, YAP1 and RPA1 were functional genes with significant sensitivity score in BC cell lines. In conclusion, the consensus strategy identifies both well-known pathogenic genes and prioritized genes that need to be further explored.</jats:p>
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    Gene Prioritization through Consensus Strategy, Enrichment Methodologies Analysis, and Networking for Osteosarcoma Pathogenesis
    (MDPI AG, 2020-02-05)
    Alejandro Cabrera-Andrade
    ;
    Andrés López-Cortés
    ;
    Gabriela Jaramillo-Koupermann
    ;
    ;
    Yunierkis Pérez-Castillo
    <jats:p>Osteosarcoma is the most common subtype of primary bone cancer, affecting mostly adolescents. In recent years, several studies have focused on elucidating the molecular mechanisms of this sarcoma; however, its molecular etiology has still not been determined with precision. Therefore, we applied a consensus strategy with the use of several bioinformatics tools to prioritize genes involved in its pathogenesis. Subsequently, we assessed the physical interactions of the previously selected genes and applied a communality analysis to this protein–protein interaction network. The consensus strategy prioritized a total list of 553 genes. Our enrichment analysis validates several studies that describe the signaling pathways PI3K/AKT and MAPK/ERK as pathogenic. The gene ontology described TP53 as a principal signal transducer that chiefly mediates processes associated with cell cycle and DNA damage response It is interesting to note that the communality analysis clusters several members involved in metastasis events, such as MMP2 and MMP9, and genes associated with DNA repair complexes, like ATM, ATR, CHEK1, and RAD51. In this study, we have identified well-known pathogenic genes for osteosarcoma and prioritized genes that need to be further explored.</jats:p>
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    A Multi-Objective Approach for Anti-Osteosarcoma Cancer Agents Discovery through Drug Repurposing
    (MDPI AG, 2020-11-22)
    Alejandro Cabrera-Andrade
    ;
    Andrés López-Cortés
    ;
    Gabriela Jaramillo-Koupermann
    ;
    Humberto González-Díaz
    ;
    Alejandro Pazos
    <jats:p>Osteosarcoma is the most common type of primary malignant bone tumor. Although nowadays 5-year survival rates can reach up to 60–70%, acute complications and late effects of osteosarcoma therapy are two of the limiting factors in treatments. We developed a multi-objective algorithm for the repurposing of new anti-osteosarcoma drugs, based on the modeling of molecules with described activity for HOS, MG63, SAOS2, and U2OS cell lines in the ChEMBL database. Several predictive models were obtained for each cell line and those with accuracy greater than 0.8 were integrated into a desirability function for the final multi-objective model. An exhaustive exploration of model combinations was carried out to obtain the best multi-objective model in virtual screening. For the top 1% of the screened list, the final model showed a BEDROC = 0.562, EF = 27.6, and AUC = 0.653. The repositioning was performed on 2218 molecules described in DrugBank. Within the top-ranked drugs, we found: temsirolimus, paclitaxel, sirolimus, everolimus, and cabazitaxel, which are antineoplastic drugs described in clinical trials for cancer in general. Interestingly, we found several broad-spectrum antibiotics and antiretroviral agents. This powerful model predicts several drugs that should be studied in depth to find new chemotherapy regimens and to propose new strategies for osteosarcoma treatment.</jats:p>