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Melanoma, a malignant tumor of melanocytes, poses a significant clinical challenge due to its aggressive nature and high potential for metastasis. The advent of targeted therapy has revolutionized the treatment landscape of melanoma, particularly for tumors harboring specific genetic alterations such as BRAF V600E mutations. Despite the initial success of targeted agents, resistance inevitably arises, underscoring the need for novel therapeutic strategies. This review explores the latest advances in targeted therapy for melanoma, focusing on new molecular targets, combination therapies, and strategies to overcome resistance.
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Melanoma , Terapia Molecular Dirigida , Proteínas Proto-Oncogénicas B-raf , Humanos , Melanoma/tratamiento farmacológico , Melanoma/terapia , Melanoma/genética , Melanoma/patología , Melanoma/metabolismo , Terapia Molecular Dirigida/métodos , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Resistencia a Antineoplásicos , Mutación , Antineoplásicos/uso terapéuticoRESUMEN
Breast cancer is the most common neoplasm worldwide. Viral infections are involved with carcinogenesis, especially those caused by oncogenic Human Papillomavirus (HPV) genotypes. Despite the detection of HPV in breast carcinomas, the virus's activity against this type of cancer remains controversial. HPV infection promotes remodeling of the host's immune response, resulting in an immunosuppressive profile. This study assessed the individual role of HPV oncogenes in the cell line MDA-MB-231 transfected with the E5, E6, and E7 oncogenes and co-cultured with peripheral blood mononuclear cells. Immunophenotyping was conducted to evaluate immune system modulation. There was an increase in CD4+ T cell numbers when compared with non-transfected and transfected MDA-MB-231, especially in the Treg profile. Pro-inflammatory intracellular cytokines, such as IFN-γ, TNF-α, and IL-17, were impaired by transfected cells, and a decrease in the cytolytic activity of the CD8+ and CD56+ lymphocytes was observed in the presence of HPV oncogenes, mainly with E6 and E7. The E6 and E7 oncogenes decrease monocyte expression, activating the expected M1 profile. In the monocytes found, a pro-inflammatory role was observed according to the cytokines released in the supernatant. In conclusion, the MDA-MB-231 cell lineage transfected with HPV oncogenes can downregulate the number and function of lymphocytes and monocytes.
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Neoplasias de la Mama , Citocinas , Humanos , Femenino , Citocinas/metabolismo , Neoplasias de la Mama/inmunología , Neoplasias de la Mama/virología , Neoplasias de la Mama/genética , Línea Celular Tumoral , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/virología , Infecciones por Papillomavirus/inmunología , Infecciones por Papillomavirus/virología , Transfección , Proteínas Oncogénicas Virales/genética , Proteínas Oncogénicas Virales/inmunología , Proteínas Oncogénicas Virales/metabolismo , Papillomaviridae/genética , Papillomaviridae/inmunología , Virus del Papiloma HumanoRESUMEN
NSD3 (nuclear receptor-binding SET domain protein 3) is a member of the NSD histone methyltransferase family of proteins. In recent years, it has been identified as a potential oncogene in certain types of cancer. The NSD3 gene encodes three isoforms, the long version (NSD3L), a short version (NSD3S) and the WHISTLE isoforms. Importantly, the NSD3S isoform corresponds to the N-terminal region of the full-length protein, lacking the methyltransferase domain. The chromosomal location of NSD3 is frequently amplified across cancer types, such as breast, lung, and colon, among others. Recently, this amplification has been correlated to a chromothripsis event, that could explain the different NSD3 alterations found in cancer. The fusion proteins containing NSD3 have also been reported in leukemia (NSD3-NUP98), and in NUT (nuclear protein of the testis) midline carcinoma (NSD3-NUT). Its role as an oncogene has been described by modulating different cancer pathways through its methyltransferase activity, or the short isoform of the protein, through protein interactions. Specifically, in this review we will focus on the functions that have been characterized as methyltransferase dependent, and those that have been correlated with the expression of the NSD3S isoform. There is evidence that both the NSD3L and NSD3S isoforms are relevant for cancer progression, establishing NSD3 as a therapeutic target. However, further functional studies are needed to differentiate NSD3 oncogenic activity as dependent or independent of the catalytic domain of the protein, as well as the contribution of each isoform and its clinical significance in cancer progression.
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N-Metiltransferasa de Histona-Lisina , Neoplasias , Proteínas Nucleares , Humanos , Masculino , Carcinoma/enzimología , Leucemia/enzimología , Oncogenes , Isoformas de Proteínas/genética , N-Metiltransferasa de Histona-Lisina/metabolismo , Proteínas Nucleares/metabolismo , Neoplasias/enzimología , Neoplasias/patologíaRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: Cervical cancer is one of the most common malignancies in women that continues to be a public health problem worldwide. Human papillomavirus (HPV) infection is closely related as the causative agent of almost all cases of cervical cancer. Currently, there is no effective treatment for the persistence of HPV. Although vaccines have shown promising results in recent years, they are still a costly strategy for developing countries and have no therapeutic effect on existing infections, which is why the need arises to search for new strategies that can be used in treatment, suppressing oncogenic HPV and disease progression. Extracts of Schisandra Chinensis and Pueraria lobata have been used in traditional medicine, and it has been shown in recent years that some of their bioactive compounds have pharmacological, antioxidant, antitumor, apoptotic, and proliferation effects in HPV-positive cells. However, its mechanism of action has yet to be fully explored. AIM OF THE STUDY: The following study aimed to determine the chemical composition, antioxidant activity, and potential antiproliferative and viral oncogene effects of natural extracts of S. chinensis and P. lobata on HPV-18 positive cervical cancer cells. MATERIALS AND METHODS: The HPV-18-positive HeLa cells were treated for 24 and 48 h with the ethanolic extracts of S chinensis and P. lobata. Subsequently, cell viability was evaluated using the resazurin method, the effect on the cell cycle of the extracts (1.0, 10, and 100 µg/mL) was measured by flow cytometry, the gene of expression of the E6/E7, P53, BCL-2, and E2F-1 were determined by RT-PCR and the protein expression of p53, Ki-67, x|and Bcl-2 by immunohistochemistry. Additionally, the chemical characterization of the two extracts was carried out using LC-MS, and the total phenolics content (TPC), Total flavonoid content (TFC), and DPPH radical scavenging capacity were determined. Data were analyzed using the Mann-Whitney and Kruskal Wallis U test with GraphPad Prism 6 software. RESULTS: The natural extracts of Schisandra chinensis and Pueraria lobata induced down-regulation of E6 HPV oncogene (p<0.05) and a strong up-regulation of P53 (p<0.05), E2F-1 (p<0.05), and Bcl-2 (p<0.05) gene expression. Simultaneously, the natural extracts tend to increase the p53 protein levels and arrest the cell cycle of HeLa in the G1/S phase (p<0.05). Investigated extracts were characterized by the occurrence of bioactive lignans and isoflavones in S. chinensis and P. lobata, respectively. CONCLUSION: The extracts of S. chinensis and P. lobata within their chemical characterization mainly present lignan and isoflavone-type compounds, which are probably responsible for inhibiting the expression of the HPV E6 oncogene and inducing an increase in the expression of p53, Bcl -2 and E2F-1 producing cell cycle detection in S phase in HeLa cells. Therefore, these extracts are good candidates to continue studying their antiviral and antiproliferative potential in cells transformed by HPV.
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Infecciones por Papillomavirus , Pueraria , Schisandra , Neoplasias del Cuello Uterino , Humanos , Femenino , Células HeLa , Virus del Papiloma Humano , Proteína p53 Supresora de Tumor/genética , Neoplasias del Cuello Uterino/tratamiento farmacológico , Regulación hacia Abajo , Infecciones por Papillomavirus/tratamiento farmacológico , Oncogenes , Proteínas Proto-Oncogénicas c-bcl-2 , AntioxidantesRESUMEN
Background: Core binding factor acute myeloid leukemia (CBF-AML) comprises t(8;21) and inv(16) and usually has a favorable prognosis. However, a wide spectrum of secondary genetic aberrations has been shown to be associated with worse outcomes with respect to overall survival (OS) and relapse. We aimed to identify secondary molecular and chromosomal aberrations within each group of CBF-AML, i.e., t(8;21) and inv(16), and to evaluate their prognosis with OS. Methods: Using the Mitelman Database of Chromosome Aberrations and Gene Fusions in Cancer, we analyzed 193 cases of CBF-AML reported between 2011 and 2021. We conducted a survival analysis to determine the 5-year OS, and we conducted univariate and multivariate Cox regression to identify independent genetic factors related to OS. Results: Among the 193 cases with CBF-AML, structural and numerical chromosome rearrangements were 25.9% and 40.9%, respectively, and secondary genetic mutations were 54.9%. The 5-year OS for the presence of del(7) and trisomy 22 was significantly worse. NRAS mutations had a worse 5-year OS in the t(8;21) group in the univariate analysis but showed no significant difference in the multivariate analysis. Conclusions: CBF-AML has heterogeneous cytogenetic characteristics but no difference in the 5-year OS between the inv(16) and t(8;21) groups. Finally, the presence of del(7), trisomy 22 and NRAS mutations showed a potential prognostic impact in CBF-AML patients. Secondary genetic findings may need to be identified to determine its association to a worse prognosis, and in the future develop better targeted therapies in patients with CBF-AML.
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Introducción: En las últimas décadas la incidencia del cáncer tiroideo en el curso de la enfermedad nodular se ha incrementado debido a las novedosas técnicas de diagnóstico; sin embargo, la tasa de mortalidad se ha mantenido muy baja. Objetivo: Evaluar las características clínicas, epidemiológicas y quirúrgicas de pacientes con afecciones nodulares tiroideas. Métodos: Se realizó un estudio descriptivo observacional de cohorte prospectivo, longitudinal con los pacientes operados de afecciones tiroideas durante el período comprendido entre enero del 2008 y diciembre del 2018. El universo y la muestra quedaron constituidos por 467 pacientes que cumplieron con los criterios de inclusión. Resultados: Predominaron el sexo femenino (89,5 por ciento) y el grupo etario de 45-60 años (29,5 por ciento). Asociaron comorbilidades 338 pacientes y algún factor de riesgo de malignidad (6,2 por ciento). Un total de 174 pacientes manifestaron síntomas y 264 mostraron algún signo. Predominaron los reportes ecográficos (TI-RADS) y citológicos (Bethesda) tipo II (54,3 por ciento) y (55,5 por ciento), respectivamente. La hemitiroidectomía fue el procedimiento más realizado (59,9 por ciento) y la disfonía la complicación más encontrada (1,9 por ciento). Conclusiones: El diagnóstico oportuno del cáncer tiroideo en el curso de una enfermedad nodular contribuye a individualizar todas las decisiones terapéuticas atendiendo a las características de cada paciente y sus circunstancias(AU)
Introduction: In recent decades, the incidence rates of thyroid cancer in the course of nodular disease has increased due to novel diagnostic techniques; however, the mortality rate has remained very low. Objective: To evaluate the clinical, epidemiological and surgical characteristics of patients with nodular thyroid disease. Methods: A descriptive, observational, of prospective cohort, longitudinal and observational study was conducted with patients operated on for thyroid disorders during the period from January 2008 to December 2018. The study universe and sample consisted of 467 patients who met the inclusion criteria. Results: The female sex (89.5 percent) and the age group 45-60 years (29.5 percent) predominated. Comorbidities were present in 338 patients, as well as some risk factor for malignancy in 6.2 percent. A total of 174 patients manifested symptoms and 264 showed some sign. There was a predominance of echography (TI-RADS) and cytology (Bethesda) type II reports, accounting for 54.3 percent and 55.5 percent, respectively. Hemithyroidectomy was the most performed procedure (59.9 percent), while dysphonia was the most encountered complication (1.9 percent). Conclusions: Timely diagnosis of thyroid cancer in the course of nodular disease contributes to individualizing all therapeutic decisions considering the characteristics of each patient and their circumstances(AU)
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Humanos , Enfermedades de la Tiroides/epidemiología , Neoplasias de la Tiroides/epidemiología , Tiroidectomía/métodos , Epidemiología Descriptiva , Estudios Prospectivos , Estudios Longitudinales , Estudios Observacionales como AsuntoRESUMEN
Data emerged from the last 20 years of basic research on tumor antigens positioned the type I MAGE (Melanoma Antigen GEnes - I or MAGE-I) family as cancer driver factors. MAGE-I gene expression is mainly restricted to normal reproductive tissues. However, abnormal re-expression in cancer unbalances the cell status towards enhanced oncogenic activity or reduced tumor suppression. Anomalous MAGE-I gene re-expression in cancer is attributed to altered epigenetic-mediated chromatin silencing. Still, emerging data indicate that MAGE-I can be regulated at protein level. Results from different laboratories suggest that after its anomalous re-expression, specific MAGE-I proteins can be regulated by well-known signaling pathways or key cellular processes that finally potentiate the cancer cell phenotype. Thus, MAGE-I proteins both regulate and are regulated by cancer-related pathways. Here, we present an updated review highlighting the recent findings on the regulation of MAGE-I by oncogenic pathways and the potential consequences in the tumor cell behavior.
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Melanoma , Proteínas de Neoplasias , Humanos , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Antígenos de Neoplasias/genéticaRESUMEN
Introducción: Desde los inicios de este siglo se ha producido un notable incremento mundial de la tasa de incidencia del cáncer de tiroides, el cual generalmente tiene un curso larvado y asintomático. Objetivo: Profundizar en el conocimiento de los aspectos novedosos del diagnóstico oportuno y tratamiento personalizado del cáncer tiroideo. Desarrollo: El cáncer tiroideo es la enfermedad maligna más frecuente del sistema endocrino. En las últimas décadas, su incidencia se ha incrementado aceleradamente, aunque la mortalidad se ha mantenido baja. El descubrimiento y desarrollo de nuevas técnicas de imágenes, inmunológicas y moleculares, han permitido estudiar en profundidad la neoplasia de la tiroides. Esto ha favorecido avanzar en los aspectos que más han modificado la nueva actitud respecto al diagnóstico oportuno y su tratamiento. Conclusiones: En años recientes, los avances de las investigaciones básicas, clínicas y traslacionales (aplicación real de los conocimientos básicos en la práctica clínica), han transformado antiguos conceptos relacionados con el cáncer tiroideo y han dotado de nuevas herramientas para el diagnóstico oportuno y tratamiento personalizado.
Introduction: Since the beginning of this century there has been a notable increase worldwide in the incidence rate of thyroid cancer, which generally has a latent and asymptomatic course. Objectives: To deepen the knowledge of the novel aspects of timely diagnosis and treatment of thyroid cancer. Development: Thyroid cancer is the most frequent malignant disease of the endocrine system. In recent decades, its incidence has increased rapidly, although mortality has remained low. The discovery and development of new imaging, immunological and molecular techniques have made it possible to study thyroid neoplasm in depth. This has favored advancing in the aspects that have most modified the new attitude regarding timely diagnosis and its treatment. Conclusions: In recent years, advances in basic, clinical and translational research have transformed old concepts related to thyroid cancer and have equipped with new tools for timely diagnosis and personalized treatment.
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The incidence and mortality of Prostate Cancer (PCa) worldwide correlate with age and bad dietary habits. Previously, we investigated the mRNA/miRNA role on PCa development and progression using high fat diet (HFD) fed mice. Here our main goal was to investigate the effect of HFD on the expression of PCa-related miRNAs and their relevance in PCa patients. We identified 6 up- and 18 down-regulated miRNAs in TRAMP-C1 mice prostate tumors under HFD conditions using miRNA microarrays. Three down-regulated miRNAs: mmu-miR-133a-3p, -1a-3p and -29c-3p were validated in TRAMP-C1 mice prostate tumor by stem-loop RT-qPCR. Hsa-miR-133a-3p/1-3p expression levels were significantly decreased in PCa compared to normal tissues while hsa-miR-133a-3p was found to be further decreased in metastatic prostate cancer tumors compared to non-metastatic PCa. We examined the promoter region of hsa-miR-133a-3p/1-3p genes and compared methylation at these loci with mature miRNA expression. We found that hsa-miR-1-2/miR-133a-1 cluster promoter hypermethylation decreased hsa-miR-133a-3p/1-3p expression in PCa. GOLPH3 and JUP, two hsa-miR-133a-3p and miR-1-3p predicted target genes, were up-regulated in PCa. ROC analysis showed that the combination of hsa-miR-133a-3p, miR-1-3p, GOLPH3 and JUP is a promising panel biomarker to distinguish between PCa and normal adjacent tissue (NAT). These results link PCa aggressiveness to the attenuation of hsa-miR-133a-3p and miR-1-3p expression by promoter hypermethylation. Hsa-miR-133a-3p and miR-1-3p down-regulation may enhance PCa aggressiveness in part by targeting GOLPH3 and JUP.
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Kaposi's sarcoma-associated herpesvirus (KSHV), also known as human gammaherpesvirus 8 (HHV-8), contains oncogenes and proteins that modulate various cellular functions, including proliferation, differentiation, survival, and apoptosis, and is integral to KSHV infection and oncogenicity. In this review, we describe the most important KSHV genes [ORF 73 (LANA), ORF 72 (vCyclin), ORF 71 or ORFK13 (vFLIP), ORF 74 (vGPCR), ORF 16 (vBcl-2), ORF K2 (vIL-6), ORF K9 (vIRF 1)/ORF K10.5, ORF K10.6 (vIRF 3), ORF K1 (K1), ORF K15 (K15), and ORF 36 (vPK)] that have the potential to induce malignant phenotypic characteristics of Kaposi's sarcoma. These oncogenes can be explored in prospective studies as future therapeutic targets of Kaposi's sarcoma.
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Infecciones por Herpesviridae , Herpesvirus Humano 8 , Sarcoma de Kaposi , Herpesvirus Humano 8/genética , Humanos , Oncogenes , Estudios Prospectivos , Sarcoma de Kaposi/patologíaRESUMEN
Introduction: Colorectal cancer has a high incidence in the world population. Different molecular pathways, such as chromosomal instability, microsatellite instability, and epigenetics are involved in its development. Objective: To perform molecular characterization in 44 individuals with sporadic colorectal cancer. Materials and methods: We conducted mutation analyses of the APC, KRAS, TP53 y BRAF genes using Sanger sequencing techniques; microsatellite instability was determined by capillary electrophoresis with five STR genetic markers while the methylation status of the MHL1 promotor gene was analyzed using methylation-specific PCR. Results: APC, KRAS, and TP53 genes mutation frequency was 18.1%, 25%, and 4.5%, respectively; the somatic mutations detected were located more frequently in the right colon. The frequency of microsatellite instability was 27.2% and 73.1% of the tumors had the MHL1 gene methylated while 91.6% of microsatellite instability-positive tumors had the methylated MLH1 gene. The mutation profile of microsatellite stability tumors APC, KRAS, and TP53 genes was more frequent than in the microsatellite instability-positive tumors. The methylation of the MLH1 gene was the most predominant molecular alteration. Conclusions: We identified molecular alterations in different genetic pathways of the colorectal cancer patients evaluated, which are common in the carcinogenesis of this cancer. These patients showed a different mutational profile compared to other populations. Our findings confirm the molecular heterogeneity described in the development of colorectal cancer.
Introducción. El cáncer colorrectal tiene una alta incidencia en la población mundial. Diversas vías moleculares están involucradas en su desarrollo, entre ellas, la inestabilidad cromosómica, la inestabilidad microsatelital y la epigenética. Objetivo. Hacer la caracterización molecular de 44 individuos con cáncer colorrectal esporádico. Materiales y métodos. El análisis de mutaciones en los genes APC, KRAS, TP53 y BRAF se hizo mediante secuenciación de Sanger; la inestabilidad microsatelital se determinó mediante electroforesis capilar utilizando cinco marcadores de repetición corta en tándem (Short Tandem Repeat) y el estado de metilación del promotor del gen MLH1 se hizo con la técnica MS-PCR (Methylation-Specific PCR). Resultados. La frecuencia de mutación de los genes APC, KRAS y TP53 fue del 18,1, 25 y 4,5 %, respectivamente; las mutaciones detectadas se localizaron con mayor frecuencia en el colon derecho. La frecuencia de inestabilidad microsatelital fue del 27,2 % y el 73,1 % en los tumores con metilación en el gen MHL1, y el 91,6 % de los tumores con inestabilidad microsatelital presentaba metilación en el gen MLH1. En el grupo de tumores con estabilidad microsatelital, las mutaciones en los genes APC, KRAS y TP53 fueron más frecuentes que en el grupo de tumores con inestabilidad microsatelital. La metilación del gen MLH1 fue la alteración más predominante. Conclusiones. En los pacientes con cáncer colorrectal evaluados se demostró la presencia de alteraciones moleculares en las diferentes vías genéticas, las cuales son comunes en su carcinogénesis. Los pacientes presentaron un perfil de mutaciones diferente al de otras poblaciones. Los hallazgos obtenidos en este estudio confirman la heterogeneidad molecular descrita en el desarrollo del cáncer colorrectal.
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Neoplasias Colorrectales , Inestabilidad de Microsatélites , Neoplasias Colorrectales/genética , Humanos , Proteínas Proto-Oncogénicas p21(ras)/genética , Estudios RetrospectivosRESUMEN
First described in 1817, prostate cancer is considered a complex neoplastic entity, and one of the main causes of death in men in the western world. In dogs, prostatic carcinoma (PC) exhibits undifferentiated morphology with different phenotypes, is hormonally independent of aggressive character, and has high rates of metastasis to different organs. Although in humans, the risk factors for tumor development are known, in dogs, this scenario is still unclear, especially regarding castration. Therefore, with the advent of molecular biology, studies were and are carried out with the aim of identifying the main molecular mechanisms and signaling pathways involved in the carcinogenesis and progression of canine PC, aiming to identify potential biomarkers for diagnosis, prognosis, and targeted treatment. However, there are extensive gaps to be filled, especially when considering the dog as experimental model for the study of this neoplasm in humans. Thus, due to the complexity of the subject, the objective of this review is to present the main pathobiological aspects of canine PC from a comparative point of view to the same neoplasm in the human species, addressing the historical context and current understanding in the scientific field.
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Introducción. El cáncer colorrectal tiene una alta incidencia en la población mundial. Diversas vías moleculares están involucradas en su desarrollo, entre ellas, la inestabilidad cromosómica, la inestabilidad microsatelital y la epigenética. Objetivo. Hacer la caracterización molecular de 44 individuos con cáncer colorrectal esporádico. Materiales y métodos. El análisis de mutaciones en los genes APC, KRAS, TP53 y BRAF se hizo mediante secuenciación de Sanger; la inestabilidad microsatelital se determinó mediante electroforesis capilar utilizando cinco marcadores de repetición corta en tándem (Short Tandem Repeat) y el estado de metilación del promotor del gen MLH1 se hizo con la técnica MS-PCR (Methylation-Specific PCR). Resultados. La frecuencia de mutación de los genes APC, KRAS y TP53 fue del 18,1, 25 y 4,5 %, respectivamente; las mutaciones detectadas se localizaron con mayor frecuencia en el colon derecho. La frecuencia de inestabilidad microsatelital fue del 27,2 % y el 73,1 % en los tumores con metilación en el gen MHL1, y el 91,6 % de los tumores con inestabilidad microsatelital presentaba metilación en el gen MLH1. En el grupo de tumores con estabilidad microsatelital, las mutaciones en los genes APC, KRAS y TP53 fueron más frecuentes que en el grupo de tumores con inestabilidad microsatelital. La metilación del gen MLH1 fue la alteración más predominante. Conclusiones. En los pacientes con cáncer colorrectal evaluados se demostró la presencia de alteraciones moleculares en las diferentes vías genéticas, las cuales son comunes en su carcinogénesis. Los pacientes presentaron un perfil de mutaciones diferente al de otras poblaciones. Los hallazgos obtenidos en este estudio confirman la heterogeneidad molecular descrita en el desarrollo del cáncer colorrectal.
Introduction: Colorectal cancer has a high incidence in the world population. Different molecular pathways, such as chromosomal instability, microsatellite instability, and epigenetics are involved in its development. Objective: To perform molecular characterization in 44 individuals with sporadic colorectal cancer. Materials and methods: We conducted mutation analyses of the APC, KRAS, TP53 y BRAF genes using Sanger sequencing techniques; microsatellite instability was determined by capillary electrophoresis with five STR genetic markers while the methylation status of the MHL1 promotor gene was analyzed using methylation-specific PCR. Results: APC, KRAS, and TP53 genes mutation frequency was 18.1%, 25%, and 4.5%, respectively; the somatic mutations detected were located more frequently in the right colon. The frequency of microsatellite instability was 27.2% and 73.1% of the tumors had the MHL1 gene methylated while 91.6% of microsatellite instability-positive tumors had the methylated MLH1 gene. The mutation profile of microsatellite stability tumors APC, KRAS, and TP53 genes was more frequent than in the microsatellite instability-positive tumors. The methylation of the MLH1 gene was the most predominant molecular alteration. Conclusions: We identified molecular alterations in different genetic pathways of the colorectal cancer patients evaluated, which are common in the carcinogenesis of this cancer. These patients showed a different mutational profile compared to other populations. Our findings confirm the molecular heterogeneity described in the development of colorectal cancer.
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Neoplasias Colorrectales/genética , Oncogenes , Genes Supresores de Tumor , Heterogeneidad Genética , Inestabilidad de Microsatélites , EpigenómicaRESUMEN
Prostate cancers may reactivate a latent embryonic program called the epithelial-mesenchymal transition (EMT) during the development of metastatic disease. Through EMT, tumors can develop a mesenchymal phenotype similar to cancer stem cell traits that contributes to metastasis and variation in therapeutic responses. Some of the recurrent somatic mutations of prostate cancer affect EMT driver genes and effector transcription factors that induce the chromatin- and androgen-dependent epigenetic alterations that characterize castrate-resistant prostate cancer (CRPC). EMT regulators in prostate cancer comprise transcription factors (SNAI1/2, ZEB1, TWIST1, and ETS), tumor suppressor genes (RB1, PTEN, and TP53), and post-transcriptional regulators (miRNAs) that under the selective pressures of antiandrogen therapy can develop an androgen-independent metastatic phenotype. In prostate cancer mouse models of EMT, Slug expression, as well as WNT/ß-Catenin and notch signaling pathways, have been shown to increase stemness potential. Recent single-cell transcriptomic studies also suggest that the stemness phenotype of advanced prostate cancer may be related to EMT. Other evidence correlates EMT and stemness with immune evasion, for example, activation of the polycomb repressor complex I, promoting EMT and stemness and cytokine secretion through RB1, TP53, and PRC1. These findings are helping clinical trials in CRPC that seek to understand how drugs and biomarkers related to the acquisition of EMT can improve drug response.
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Biomarcadores de Tumor/genética , Transición Epitelial-Mesenquimal/genética , Células Madre Neoplásicas/metabolismo , Neoplasias de la Próstata Resistentes a la Castración/genética , Neoplasias de la Próstata Resistentes a la Castración/metabolismo , Transducción de Señal/genética , Animales , Humanos , Masculino , Medicina de Precisión/métodosRESUMEN
Immunotherapy has improved patient survival in many types of cancer, but for prostate cancer, initial results with immunotherapy have been disappointing. Prostate cancer is considered an immunologically excluded or cold tumor, unable to generate an effective T-cell response against cancer cells. However, a small but significant percentage of patients do respond to immunotherapy, suggesting that some specific molecular subtypes of this tumor may have a better response to checkpoint inhibitors. Recent findings suggest that, in addition to their function as cancer genes, somatic mutations of PTEN, TP53, RB1, CDK12, and DNA repair, or specific activation of regulatory pathways, such as ETS or MYC, may also facilitate immune evasion of the host response against cancer. This review presents an update of recent discoveries about the role that the common somatic mutations can play in changing the tumor microenvironment and immune response against prostate cancer. We describe how detailed molecular genetic analyses of the tumor microenvironment of prostate cancer using mouse models and human tumors are providing new insights into the cell types and pathways mediating immune responses. These analyses are helping researchers to design drug combinations that are more likely to target the molecular and immunological pathways that underlie treatment failure.
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Inmunoterapia , Neoplasias de la Próstata/genética , Microambiente Tumoral/inmunología , Animales , Ensayos Clínicos como Asunto , Genes Relacionados con las Neoplasias , Humanos , Masculino , Mutación , Neoplasias Experimentales/inmunología , Neoplasias de la Próstata/inmunología , Análisis de la Célula Individual , Análisis Espacial , Microambiente Tumoral/genéticaRESUMEN
Arsenic is considered a worldwide pollutant that can be present in drinking water. Arsenic exposure is associated with various diseases, including cancer. Antioxidants as selenite and α-tocopherol-succinate have been shown to modulate arsenic toxic effects. Since changes in STAT3 and PSMD10 gene expression have been associated with carcinogenesis, the aim of this study was to evaluate the effect of arsenic exposure and co-treatments with selenite or α-tocopherol-succinate on the expression of these genes, in the livers of chronically exposed Syrian golden hamsters. Animals were divided into six groups: (i) control, (ii) chronically treated with 100 ppm arsenic, (iii) treated with 6 ppm α-tocopherol-succinate (α-TOS), (iv) treated with 8.5 ppm selenite, (v) treated with arsenic + α-TOS, and (vi) treated with arsenic + selenite. Urine samples and livers were collected after 20 weeks of continuous exposure. The urine samples were analyzed for arsenic species by atomic absorption spectrophotometry, and real-time RT-qPCR analysis was performed for gene expression evaluation. A reduction in STAT3 expression was observed in the selenite-treated group. No differences in PSMD10 expression were found among groups. Histopathological analysis revealed hepatic lymphocytosis in selenite-treated animals. As a conclusion, long-term exposure to arsenic does not significantly alter the expression of STAT3 and PSMD10 oncogenes in the livers of hamsters; however, selenite down-regulates STAT3 expression and provokes lymphocytosis.
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Antioxidantes/farmacología , Arsénico/efectos adversos , Hígado/efectos de los fármacos , Linfocitosis/inducido químicamente , Factor de Transcripción STAT3/genética , Ácido Selenioso/farmacología , Administración Oral , Animales , Antioxidantes/administración & dosificación , Arsénico/administración & dosificación , Arsénico/orina , Regulación hacia Abajo/efectos de los fármacos , Estimación de Kaplan-Meier , Hígado/patología , Masculino , Mesocricetus , Complejo de la Endopetidasa Proteasomal/genética , Complejo de la Endopetidasa Proteasomal/metabolismo , Factor de Transcripción STAT3/metabolismo , Ácido Selenioso/administración & dosificación , Aumento de Peso/efectos de los fármacos , alfa-Tocoferol/farmacología , alfa-Tocoferol/uso terapéuticoRESUMEN
El cáncer constituye la segunda de causa de muerte a nivel mundial y se estima será la primera, superando a las cardiovasculares. El estudio de sus bases moleculares ha permitido el desarrollo de la quimioterapia clásica, como de nuevas terapias biológicas. Si bien estos avances han redundado en un aumento en la sobrevida, no ha impactado en una menor incidencia de los casos. Esto último se debe, en parte, al desconocimiento de los múltiples factores carcinogénicos existentes y los efectos de sus interacciones para cada uno de los tumores. En este sentido, es interesante notar que, en los currículos de las escuelas de salud de las universidades chilenas, el cáncer u oncología como tal, no constituye una cátedra en sí misma, siendo sus contenidos tangencialmente abordados en distintos momentos de la formación; en biología celular, medicina interna y cirugía, entre otros. Con estos antecedentes, el propósito de este trabajo es ofrecer un propuesta sencilla y accesible para los estudiantes, respecto de los contenidos que, a nuestro juicio, son esenciales para comprender las bases biológicas de esta enfermedad y enfrentar con mejores conocimientos el ciclo clínico posterior. A continuación, el lector se encontrará con principios fundamentales de la biología humana normal (como el ciclo celular y el dogma central de la biología molecular), que permiten obtener una visión global de los mecanismos fisiológicos cuya desregulación conlleva a una neoplasia maligna. Luego se entregarán algunas definiciones amplias en relación con los conceptos de neoplasia, tumor benigno y maligno. Para, finalmente, abordar las principales etapas que permiten el desarrollo del cáncer; (i) iniciación, (ii) promoción y (iii) progresión. En esta última, se profundizará por separado, en angiogénesis, degradación de la matriz extracelular, migración y evasión de la respuesta inmune. Este trabajo no aborda materias relacionadas con la hipótesis metabólica del cáncer.
Cancer constitutes the second most common cause of death worldwide and is expected to become the leading one, even above cardiovascular diseases. The understanding of the cellular and molecular basis of cancer has led not only to the proper development of chemotherapy but also of target therapies. Although these advances are related with improved survival rates among cancer patients, it has poorly impacted its incidences. In this regard, the lack of knowledge regarding the impact that the several carcinogenic factors and their interactions have on different types of cancers may explain at least in part the difficulties to reduce incidence rates. However, is worth noticing that in several health schools of chilean universities, cancer does not constitute a formal course, being only partially approached during other courses, such as cell biology, internal medicine, and surgery. Thus, the aim of our work is to provide students a simple and resumed manuscript about essential topics necessary to understand the biological basis of cancer. First, the reader will find some fundamentals about human biology including the cell cycle and the central dogma of molecular biology, which offers an overview of the physiological mechanisms leading to malignant neoplasia. Then, we will provide current definitions of neoplasia, benign and malignant tumors are provided. Finally, the different stages of tumor progression will be approached to allow the understanding of cancer development. These stages include (i) initiation, (ii) promotion, and (iii) progression. For the last one, metastasis, angiogenesis, extracellular matrix degradation, migration, and immune evasion will also be addressed. This work will not consider the metabolic hypothesis of cancer.
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Educación de Pregrado en Medicina , Neoplasias/microbiología , CurriculumRESUMEN
Introducción: El cáncer pulmonar constituye un serio problema de salud mundial por su elevada prevalencia y mortalidad. En la carcinogénesis pulmonar están implicados oncogenes y genes supresores tumorales, que en una compleja interacción con factores ambientales favorecen la transformación cancerosa. Objetivo: Describir los principales genes implicados en el cáncer pulmonar. Métodos: Se buscaron referencias en las bases de datos PubMed Central, Annual Reviews y SciELO. Se revisaron preferentemente los artículos originales, las revisiones bibliográficas, las revisiones sistemáticas y los metaanálisis de los últimos cinco años. Análisis e integración de la información: En la carcinogénesis pulmonar se involucran los oncogenes JUN, FOS, ABL1, BRAF, RAF1, GNAS, KRAS, NRAS, HRAS, CSF 1R, MYC, EGFR, MET, ALK, CCNE1, DDR2, ERBB3, FGFR1, MDM2, ROS1, SOX2 y TP63 y los genes supresores tumorales TP53, CDKN2A, CDKN1A, RB1, CDK2AP1, ATM, ERCC2, BRCA1, CCND1, STK11, PDLIM2, PTEN, ARID1A, ASCL4, CUL3, EP300, KEAP1, KMT2D, NF1, NOTCH1, RASA1, ETD2 y SMARCA4. El conocimiento de la genética molecular del cáncer pulmonar es importante para la identificación de biomarcadores diagnósticos y pronósticos más eficaces y para el diseño de fármacos diana sobre genes específicos(AU)
Introduction: Lung cancer is a serious global health problem due to its high prevalence and mortality. Lung carcinogenesis involves oncogenes and tumor suppressor genes which interact in complex manners with environmental factors, paving the way for the cancerous transformation. Objective: Describe the main genes involved in lung cancer. Methods: References were searched for in the databases PubMed Central, Annual Reviews and SciELO. Particular attention was paid to original papers, bibliographic reviews, systematic reviews and meta-analyses published in the last five years. Data analysis and integration: Lung carcinogenesis involves the oncogenes JUN, FOS, ABL1, BRAF, RAF1, GNAS, KRAS, NRAS, HRAS, CSF 1R, MYC, EGFR, MET, ALK, CCNE1, DDR2, ERBB3, FGFR1, MDM2, ROS1, SOX2 and TP63, and the tumor suppressor genes TP53, CDKN2A, CDKN1A, RB1, CDK2AP1, ATM, ERCC2, BRCA1, CCND1, STK11, PDLIM2, PTEN, ARID1A, ASCL4, CUL3, EP300, KEAP1, KMT2D, NF1, NOTCH1, RASA1, ETD2 and SMARCA4. Knowledge about the molecular genetics of lung cancer is important to identify more efficient diagnostic and prognostic biomarkers and to design targeted drugs for specific genes(AU)
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Humanos , Oncogenes , Biomarcadores , Genes Supresores de TumorRESUMEN
Cholesteatomas are frequent middle ear benign tumors of unknown etiology. Infectious agents have been considered as possible contributing factors in the pathogenesis of cholesteatomas. Aiming to investigate the presence of respiratory viruses in primary cholesteatoma tissues, 26 formalin-fixed paraffin-embedded primary cholesteatoma tissues obtained from patients seen at the of the Clinical Hospital of the University of São Paulo School of Medicine, in Ribeirão Preto, Brazil were tested by real-time polymerase chain reaction (PCR). Considering the PCR results, 35% of the tissues were positive for human rhinovirus (HRV), 15.3% for human enterovirus (EV), 3.8% for human metapneumovirus (HMPV), and 3.8% for human bocavirus (HBoV). Serial immunohistochemistry for virus antigens and cell surface markers evidenced that the viruses were associated with fibroblasts, dendritic cells, macrophages, B lymphocytes, CD4+ , and CD8+ T lymphocytes. These findings indicate for the first time the presence of active respiratory virus infection in primary cholesteatoma tissues, suggesting that persisting virus infection in the middle could play a role in the pathogenesis and evolution of cholesteatomas.