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Hepatocellular carcinoma (HCC) development is associated with altered modifications in DNA methylation, changing transcriptional regulation. Emerging evidence indicates that DNA methyltransferase 1 (DNMT1) plays a key role in the carcinogenesis process. This study aimed to investigate how pirfenidone (PFD) modifies this pathway and the effect generated by the association between c-Myc expression and DNMT1 activation. Rats F344 were used for HCC development using 50 mg/kg of diethylnitrosamine (DEN) and 25 mg/kg of 2-Acetylaminofluorene (2-AAF). The HCC/PFD group received simultaneous doses of 300 mg/kg of PFD. All treatments lasted 12 weeks. On the other hand, HepG2 cells were used to evaluate the effects of PFD in restoring DNA methylation in the presence of the inhibitor 5-Aza. Histopathological, biochemical, immunohistochemical, and western blot analysis were carried out and our findings showed that PFD treatment reduced the amount and size of tumors along with decreased Glipican-3, ß-catenin, and c-Myc expression in nuclear fractions. Also, this treatment improved lipid metabolism by modulating PPARγ and SREBP1 signaling. Interestingly, PFD augmented DNMT1 and DNMT3a protein expression, which restores global methylation, both in our in vivo and in vitro models. In conclusion, our results suggest that PFD could slow down HCC development by controlling DNA methylation.
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Carcinoma Hepatocelular , DNA (Citosina-5-)-Metiltransferase 1 , Metilação de DNA , Antígeno Nuclear de Célula em Proliferação , Piridonas , Animais , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , DNA (Citosina-5-)-Metiltransferase 1/genética , Metilação de DNA/efeitos dos fármacos , Metilação de DNA/genética , Piridonas/farmacologia , Ratos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Humanos , Células Hep G2 , Antígeno Nuclear de Célula em Proliferação/metabolismo , Masculino , Ratos Endogâmicos F344 , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Dietilnitrosamina , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Neoplasias Hepáticas Experimentais/patologia , Neoplasias Hepáticas Experimentais/metabolismo , Neoplasias Hepáticas Experimentais/genéticaRESUMO
Anti-CD19 CAR-T cell therapy represents a breakthrough in the treatment of B-cell malignancies, and it is expected that this therapy modality will soon cover a range of solid tumors as well. Therefore, a universal cheap and sensitive method to detect CAR expression is of foremost importance. One possibility is the use of epitope tags such as c-Myc, HA or FLAG tags attached to the CAR extracellular domain, however, it is important to determine whether these tags can influence binding of the CAR with its target molecule. Here, we conducted in-silico structural modelling of an FMC63-based anti-CD19 single-chain variable fragment (scFv) with and without a c-Myc peptide tag added to the N-terminus portion and performed molecular dynamics simulation of the scFv with the CD19 target. We show that the c-Myc tag presence in the N-terminus portion does not affect the scFv's structural equilibrium and grants more stability to the scFv. However, intermolecular interaction potential (IIP) analysis reveals that the tag can approximate the complementarity-determining regions (CDRs) present in the scFv and cause steric impediment, potentially disturbing interaction with the CD19 protein. We then tested this possibility with CAR-T cells generated from human donors in a Nalm-6 leukemia model, showing that CAR-T cells with the c-Myc tag have overall worse antitumor activity, which was also observed when the tag was added to the C-terminus position. Ultimately, our results suggest that tag addition is an important aspect of CAR design and can influence CAR-T cell function, therefore its use should be carefully considered.
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The metabolic reprogramming that promotes tumorigenesis in glioblastoma is induced by dynamic alterations in the hypoxic tumor microenvironment, as well as in transcriptional and signaling networks, which result in changes in global genetic expression. The signaling pathways PI3K/AKT/mTOR and RAS/RAF/MEK/ERK stimulate cell metabolism, either directly or indirectly, by modulating the transcriptional factors p53, HIF1, and c-Myc. The overexpression of HIF1 and c-Myc, master regulators of cellular metabolism, is a key contributor to the synthesis of bioenergetic molecules that mediate glioma cell transformation, proliferation, survival, migration, and invasion by modifying the transcription levels of key gene groups involved in metabolism. Meanwhile, the tumor-suppressing protein p53, which negatively regulates HIF1 and c-Myc, is often lost in glioblastoma. Alterations in this triad of transcriptional factors induce a metabolic shift in glioma cells that allows them to adapt and survive changes such as mutations, hypoxia, acidosis, the presence of reactive oxygen species, and nutrient deprivation, by modulating the activity and expression of signaling molecules, enzymes, metabolites, transporters, and regulators involved in glycolysis and glutamine metabolism, the pentose phosphate cycle, the tricarboxylic acid cycle, and oxidative phosphorylation, as well as the synthesis and degradation of fatty acids and nucleic acids. This review summarizes our current knowledge on the role of HIF1, c-Myc, and p53 in the genic regulatory network for metabolism in glioma cells, as well as potential therapeutic inhibitors of these factors.
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Myc and Max are essential proteins in the development of prostate cancer. They act by dimerizing and binding to E-box sequences. Disrupting the Myc:Max heterodimer interaction or its binding to E-box sequences to interrupt gene transcription represent promising strategies for treating cancer. We designed novel pMyc and pMax peptides from reference sequences, and we evaluated their ability to bind specifically to E-box sequences using an electrophoretic mobility shift assay (EMSA). Then, we assembled nanosystems (NSs) by coupling pMyc and pMax peptides to AuNPs, and determined peptide conjugation using UV-Vis spectroscopy. After that, we characterized the NS to obtain the nanoparticle's size, hydrodynamic diameter, and zeta potential. Finally, we evaluated hemocompatibility and cytotoxic effects in three different prostate adenocarcinoma cell lines (LNCaP, PC-3, and DU145) and a non-cancerous cell line (Vero CCL-81). EMSA results suggests peptide-nucleic acid interactions between the pMyc:pMax dimer and the E-box. The hemolysis test showed little hemolytic activity for the NS at the concentrations (5, 0.5, and 0.05 ng/µL) we evaluated. Cell viability assays showed NS cytotoxicity. Overall, results suggest that the NS with pMyc and pMax peptides might be suitable for further research regarding Myc-driven prostate adenocarcinomas.
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The transcription factors Oct4, Sox2, Klf4, and c-Myc enable the reprogramming of somatic cells into induced pluripotent cells. Reprogramming generates newly differentiated cells for potential therapies in cancer, neurodegenerative diseases, and rejuvenation processes. In cancer therapies, these transcription factors lead to a reduction in the size and aggressiveness of certain tumors, such as sarcomas, and in neurodegenerative diseases, they enable the production of dopaminergic cells in Parkinson's disease, the replacement of affected neuronal cells in olivopontocerebellar atrophy, and the regeneration of the optic nerve. However, there are limitations, such as an increased risk of cancer development when using Klf4 and c-Myc and the occurrence of abnormal dyskinesias in the medium term, possibly generated by the uncontrolled growth of differentiated dopaminergic cells and the impairment of the survival of the new cells. Therefore, the Yamanaka transcription factors have shown therapeutic potential through cell reprogramming for some carcinomas, neurodegenerative diseases, and rejuvenation. However, the limitations found in the studies require further investigation before the use of these transcription factors in humans.
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Carcinoma , Sarcoma , Humanos , Agressão , Diferenciação Celular/genética , Laboratórios , Fator 3 de Transcrição de Octâmero/genética , Fator 4 Semelhante a Kruppel , Fatores de Transcrição SOXB1 , Proteínas Proto-Oncogênicas c-mycRESUMO
Tumoral microRNAs, such as miR-125b and miR-155b, are important gene expression regulators with complex pathogenetic mechanisms. However, their role in DLBCL, especially when cell-of-origin classification is considered, are still to be elucidated. In a series of 139 DLBCL cases considering germinal center (GC) versus nonGC subtypes, we investigated miR-125b and miR-155b expression by in situ hibridization and their association with some immunophenotypic presentations, including MYC, BCL2 and TP53 expression, MYC, BCL2 and BCL6 translocation status, as well as clinicopathological features and outcomes. miR-125b detection was positively correlated to the Ki-67 index (P = 0.035) in the nGC. Considering the GC subgroup, the percentage of miR-125b positive cells was also correlated to either MYC and MYC/BCL2 double expression (P = 0.047 and P = 0.049, respectively). When it comes to nGC patients, miR-155b percentage and intensity, as well as Allred score, were positively correlated to disease progression (P = 0.038, P = 0.057 and P = 0.039, respectively). In a multivariate analysis, GC phenotype was a significant independent factor associated with higher OS (P = 0.007) and, considering the nGC group, although not significant, the expression of TP53, miR-125b and miR-155b seems to be potential prognostic biomarkers in these tumors. This study demonstrated different pathways based on cell-of-origin classification and highlighted different clinical outcomes. miR-125b, miR-155b and TP53 expression may also represent potential prognostic factors in nGC-DLBCL.
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Linfoma Difuso de Grandes Células B , MicroRNAs , Humanos , Prognóstico , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/tratamento farmacológico , MicroRNAs/genética , MicroRNAs/uso terapêutico , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/uso terapêuticoRESUMO
Clausena excavata is a famous folklore medicinal plant in Asian region that is being used for the treatment of different disorders. This study investigated the cytotoxic effects of leaf extracts via MTT assay, as well as the in vitro apoptotic activities of the ethyl acetate C. excavata leaf extract (EACE) on human Burkitt's lymphoma, Raji, cell line using annexin-V-FITC/propidium iodide flow cytometric assays. Pro-apoptotic (BAX) and anti-apoptotic (BCL-2, c-MYC) gene expressions were determined via real-time quantitative PCR. Phytochemical screening was done by Gas chromatography-mass spectrometry (GC-MS). EACE has the lowest IC50 (19.3 ± 0.35 µg/mL) among extracts. EACE-treated Raji cells after 48 h underwent apoptosis as evident by loss of cell viability and increase in the percentage of early and late apoptotic cells. The results also showed EACE mediated decreased in the BCL-2 and c-MYC gene expressions and increased in the BAX gene. C. excavata is a potential treatment for Burkitt lymphoma through activation of apoptosis.
Clausena excavata es una planta medicinal tradicional famosa en la región asiática que se utiliza para el tratamiento de diferentes trastornos. Este estudio investigó los efectos citotóxicos de los extractos de hojas a través del ensayo MTT, así como las actividades apoptóticas in vitro del extracto de hoja de acetato de etilo de C. excavata (EACE) en la línea celular de linfoma de Burkitt humano, Raji, usando citometría de flujo de yoduro de anexina-V-FITC/propidio. Las expresiones génicas proapoptóticas (BAX) y antiapoptóticas (BCL-2, c-MYC) se determinaron mediante PCR cuantitativa en tiempo real. El cribado fitoquímico se realizó mediante cromatografía de gases-espectrometría de masas (GC-MS). EACE tiene el IC50más bajo (19,3 ± 0,35 µg/mL) entre los extractos. Las células Raji tratadas con EACE después de 48 h sufrieron apoptosis como es evidente por la pérdida de viabilidad celular y el aumento en el porcentaje de células apoptóticas tempranas y tardías. Los resultados también mostraron una disminución mediada por EACE en las expresiones de los genes BCL-2 y c-MYC y un aumento en el gen BAX. C. excavata es un tratamiento potencial para el linfoma de Burkitt a través de la activación de la apoptosis.
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Óleos Voláteis/farmacologia , Linfoma de Burkitt/tratamento farmacológico , Clausena/química , Plantas Medicinais , Óleos Voláteis/química , Linfoma de Burkitt/prevenção & controle , Apoptose/efeitos dos fármacosRESUMO
This study aimed to identify Mycoplasma bovis, Myc. dispar, and Myc. bovirhinis, which are involved in bovine respiratory disease through a multiplex PCR as an alternative to culture's features that hamper Mycoplasma isolation. Nasal swabs were taken from 335 cattle with and without respiratory disease background (RDB) from dairy herds in the central region of Mexico. Each sample was divided in two; the first part was processed for the direct DNA extraction of the nasal swab and the second for Mycoplasma isolation, culture, and then the multiplex PCR was performed. In the nasal swabs, Myc. bovis was identified in 21.1%; Myc. dispar, in 11.8%; and Myc. bovirhinis, in 10.8% in cattle with RDB. Isolates were identified as Myc. bovis, 20.1%; Myc. dispar, 11.8%; and Myc. bovirhinis, 6.1%. There is a strong correlation between the presence of Mycoplasma identified by PCR and the clinical history of the disease (ρ < 0.0000). In animals without RDB, Myc. bovirhinis was the only species detected in 6.1% of the samples processed directly for multiplex PCR, and in 2% of the isolates. There is an excellent correlation (kappa 0.803) between the isolation and the 16S PCR and a high correlation (kappa 0.75) between the isolation and the multiplex PCR. Therefore, we conclude that the PCR multiplex test is highly sensitive and may be used for the diagnosis and surveillance of the three species in biological samples and mycoplasma isolates.
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Doenças dos Bovinos , Mycoplasma bovis , Transtornos Respiratórios , Doenças Respiratórias , Bovinos , Animais , Reação em Cadeia da Polimerase Multiplex/veterinária , Prevalência , México/epidemiologia , Transtornos Respiratórios/veterinária , Doenças Respiratórias/veterinária , Mycoplasma bovis/genética , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/epidemiologiaRESUMO
Colorectal cancer (CRC) is a malignant tumor initiating from the mucosa of the colorectum. According to the 2020 statistics from the World Health Organization, there are 10.0% CRC cases among all 19.3 million new cancers, followed by lung and breast cancer, and 9.4% CRC cases among all 9.9 million cancer deaths, ranking second. The population of CRC patients in China is large, and its incidence and mortality continue to increase each year. Despite the continuous development of surgical methods, chemotherapy, radiotherapy, targeted therapy and immunotherapy, the overall survival of CRC patients remains low. Past research has suggested that c-myc plays a pivotal role in the development of CRC. A higher expression level of c-Myc is a negative prognostic marker in CRC. However, there are few drugs targeting c-myc directly. Therefore, we focused on discovering the mechanism of c-myc in CRC to provide a reference for a better therapy choice for patients.
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Neoplasias Colorretais , Proteínas Proto-Oncogênicas c-myc , China , Neoplasias Colorretais/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismoRESUMO
Gastric cancer (GC) is the fifth most common type of tumor and the third leading cause of cancer death worldwide. The evolution of gastric carcinogenesis is still poorly understood and, for this reason, preclinical research protocols were established that included the development of gastric cancer cell lines and the establishment of models of gastric carcinogenesis in non-human primates such as Sapajus apella. A comprehensive literature search was performed in relevant databases such as PubMed, ResearchGate, and Google Scholar to identify studies related to the topic. After an in-depth study of these reports, significant data were collected and compiled under appropriate headings. The main result of the studies carried out by the group on GC is the demonstration of the MYC gene overexpression as a common phenomenon in stomach carcinogenesis. Furthermore, we revealed that reducing the expression of the CDC25B gene, regulated by the MYC protein, is a therapeutic strategy against stomach tumors. This review article reveals preclinical evidence that treatment with menadione in experimental models of gastric tumorigenesis, in vivo and in vitro, inhibits the action of the phosphatase CDC25B and, consequently, prevents cell proliferation, invasion, and migration.
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Neoplasias Gástricas , Animais , Carcinogênese/genética , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Genes myc , Neoplasias Gástricas/metabolismo , Vitamina K 3/farmacologia , Fosfatases cdc25/genética , Fosfatases cdc25/metabolismoRESUMO
Long non-coding RNA (lncRNA) such as ANRIL and UFC1 have been verified as oncogenic genes in non-small cell lung cancer (NSCLC). It is well known that the tumor suppressor microRNA-34a (miR-34a) is downregulated in NSCLC. Furthermore, miR-34a induces senescence and apoptosis in breast, glioma, cervical cancer including NSCLC by targeting Myc. Recent evidence suggests that these two lncRNAs act as a miR-34a sponge in corresponding cancers. However, the biological functions between these two non-coding RNAs (ncRNAs) have not yet been studied in NSCLC. Therefore, we present a Boolean model to analyze the gene regulation between these two ncRNAs in NSCLC. We compared our model to several experimental studies involving gain- or loss-of-function genes in NSCLC cells and achieved an excellent agreement. Additionally, we predict three positive circuits involving miR-34a/E2F1/ANRIL, miR-34a/E2F1/UFC1, and miR-34a/Myc/ANRIL. Our circuit- perturbation analysis shows that these circuits are important for regulating cell-fate decisions such as senescence and apoptosis. Thus, our Boolean network permits an explicit cell-fate mechanism associated with NSCLC. Therefore, our results support that ANRIL and/or UFC1 is an attractive target for drug development in tumor growth and aggressive proliferation of NSCLC, and that a valuable outcome can be achieved through the miRNA-34a/Myc pathway.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , MicroRNAs , RNA Longo não Codificante , Apoptose/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Oncogenes , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Enzimas de Conjugação de Ubiquitina/genéticaRESUMO
PURPOSE: Cutaneous angiosarcoma (CAS) is a rare but typically aggressive malignant vascular neoplasm of the skin. Tumor microenvironment (TME) of CAS and its associations with baseline clinicopathological features and patient outcomes are very important, especially when considering the recent advances in understanding of the tumor biology. METHODS/PATIENTS: We retrospectively reviewed medical records of patients who underwent surgical resection for CAS at a tertiary Hospital. The pretreated specimens were evaluated by immunohistochemistry for programmed cell death protein 1 (PD-1) and its ligand (PD-L1), densities of tumor infiltrative lymphocytes (TILs) (CD3+, CD4+, CD8+, CD45RO+, FoxP3+), as well as c-MYC and Ki-67 expressions. Overall survival (OS) was estimated by Kaplan-Meier method and compared with Log-rank test. RESULTS: A total of 21 CAS patients were identified. Median age was 67 (ranges: 20-81) years, 14 (66.7%) were male, and over 50% had lesions of scalp. Histopathological examination showed a predominantly spindle cell type (57.1%). All patients underwent surgery, 16 (76.2%) were treated further. PD-L1 was positively stained (> 1%) in tumor cells (42.9%) and TILs (23.8%). PD-1 expression (> 1%) was identified in TILs of 11 (52.4%) cases. PD-1/PD-L1 expressions were significantly associated with the higher densities of CD3+, CD4+, CD8+, CD45RO+, and Foxp3+ TILs, but not with patient characteristics or c-MYC or Ki-67 expression. Median OS was 18.5 months (95% CI 6.0-35.9), although no prognostic significance was observed with respect to any clinicopathological features. CONCLUSION: We characterized TME and its clinical and prognostic association in CAS. PD-1/PD-L1 expressions were significantly associated with TILs subtypes but not with OS.
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Antígeno B7-H1 , Hemangiossarcoma , Idoso , Antígeno B7-H1/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Feminino , Fatores de Transcrição Forkhead/metabolismo , Hemangiossarcoma/metabolismo , Hemangiossarcoma/patologia , Hemangiossarcoma/cirurgia , Humanos , Antígeno Ki-67/metabolismo , Linfócitos do Interstício Tumoral/metabolismo , Masculino , Prognóstico , Receptor de Morte Celular Programada 1/metabolismo , Estudos Retrospectivos , Microambiente TumoralRESUMO
This work describes the effects of immunotherapy with Protein Aggregate Magnesium-Ammonium Phospholinoleate-Palmitoleate Anhydride in the treatment of non-muscle invasive bladder cancer in an animal model. NMIBC was induced by treating female Fischer 344 rats with N-methyl-N-nitrosourea. After treatment with MNU, the rats were distributed into four experimental groups: Control (without MNU) group, MNU (cancer) group, MNU-BCG (Bacillus Calmette-Guerin) group, and MNU-P-MAPA group. P-MAPA intravesical treatment was more effective in histopathological recovery from cancer state in relation to BCG treatment. Western blot assays showed an increase in the protein levels of c-Myc, COUP-TFII, and wild-type p53 in P-MAPA-treated rats in relation to BCG-treated rats. In addition, rats treated with P-MAPA intravesical immunotherapy showed the highest BAX protein levels and the lowest proliferation/apoptotic ratio in relation to BCG-treated rats, pointing out a preponderance of apoptosis. P-MAPA intravesical treatment increased the wild-type p53 levels and enhanced c-Myc/COUP-TFII-induced apoptosis mediated by p53. These alterations were fundamental for histopathological recovery from cancer and for suppress abnormal cell proliferation. This action of P-MAPA on apoptotic pathways may represent a new strategy for treating NMIBC.
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Agentes de Imunomodulação/administração & dosagem , Ácidos Linoleicos/administração & dosagem , Ácidos Oleicos/administração & dosagem , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/terapia , Administração Intravesical , Animais , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Imunoterapia/métodos , Invasividade Neoplásica , Proteínas Proto-Oncogênicas c-myc/metabolismo , Ratos Endogâmicos F344 , Proteínas Repressoras/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Neoplasias da Bexiga Urinária/metabolismo , Proteína X Associada a bcl-2/metabolismoRESUMO
Hepatocellular carcinoma (HCC) is the most common form of liver cancer. The number of cases is increasing and the trend for the next few years is not encouraging. HCC is usually detected in the advanced stages of the disease, and pharmacological therapies are not entirely effective. For this reason, it is necessary to search for new therapeutic options. The objective of this work was to evaluate the effect of the drugs isotretinoin and thalidomide on c-MYC expression and cancer-related proteins in an HCC cellular model. The expression of c-MYC was measured using RT-qPCR and western blot assays. In addition, luciferase activity assays were performed for the c-MYC promoters P1 and P2 using recombinant plasmids. Dose-response-time analyses were performed for isotretinoin or thalidomide in cells transfected with the c-MYC promoters. Finally, a proteome profile analysis of cells exposed to these two drugs was performed and the results were validated by western blot. We demonstrated that in HepG2 cells, isotretinoin and thalidomide reduced c-MYC mRNA expression levels, but this decrease in expression was linked to the regulation of P1 and P1-P2 c-MYC promoter activity in isotretinoin only. Thalidomide did not exert any effect on c-MYC promoters. Also, isotretinoin and thalidomide were capable of inducing and repressing proteins associated with cancer. In conclusion, isotretinoin and thalidomide down-regulate c-MYC mRNA expression and this is partially due to P1 or P2 promoter activity, suggesting that these drugs could be promising options for modulating the expression of oncogenes and tumor suppressor genes in HCC.
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Carcinoma Hepatocelular/metabolismo , Isotretinoína/farmacologia , Neoplasias Hepáticas/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Talidomida/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Regiões Promotoras Genéticas , Proteômica/métodosRESUMO
Peritoneal lymphomatosis (PL) is a rare presentation of extranodal precursor leukemia/lymphoma. The presentation is often non-specific, leading to delayed diagnosis and treatment. In this case, though the preliminary diagnosis was established on ascitic fluid cytology, the disease progressed rapidly, leading to demise before initiating chemotherapy. Immunophenotyping and molecular studies, performed later, established a diagnosis of de novo B-cell precursor leukemia/lymphoma with MYC, BCL2 rearrangements (Double-hit lymphoma). MYC, BCL2 rearrangements are rarely reported in precursor B-lymphoma/leukemia which carry dismal prognosis. In this report, we illustrate autopsy findings of PL in an elderly gentleman who presented with ascites for evaluation.
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Chromosomal instability (CIN), the increasing rate in which cells acquire new chromosomal alterations, is one of the hallmarks of cancer. Many studies highlighted CIN as an important mechanism in the origin, progression, and relapse of acute myeloid leukemia (AML). The ambivalent feature of CIN as a cancer-promoting or cancer-suppressing mechanism might explain the prognostic variability. The latter, however, is described in very few studies. This review highlights the important CIN mechanisms in AML, showing that CIN signatures can occur largely in all the three major AML types (de novo AML, secondary-AML, and therapy-related-AML). CIN features in AML could also be age-related and reflect the heterogeneity of the disease. Although most of these abnormalities show an adverse prognostic value, they also offer a strong new perspective on personalized therapy approaches, which goes beyond assessing CIN in vitro in patient tumor samples to predict prognosis. Current and emerging AML therapies are exploring CIN to improve AML treatment, which includes blocking CIN or increasing CIN beyond the limit threshold to induce cell death. We argue that the characterization of CIN features, not included yet in the routine diagnostic of AML patients, might provide a better stratification of patients and be extended to a more personalized therapeutic approach.
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Ovarian cancer is the deadliest of gynecological malignancies with approximately 49% of women surviving 5 years after initial diagnosis. The standard of care for ovarian cancer consists of cytoreductive surgery followed by platinum-based combination chemotherapy. Unfortunately, despite initial response, platinum resistance remains a major clinical challenge. Therefore, the identification of effective biomarkers and therapeutic targets is crucial to guide therapy regimen, maximize clinical benefit, and improve patient outcome. Given the pivotal role of c-MYC deregulation in most tumor types, including ovarian cancer, assessment of c-MYC biological and clinical relevance is essential. Here, we briefly describe the frequency of c-MYC deregulation in ovarian cancer and the consequences of its targeting.
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INTRODUCTION AND OBJECTIVES: Warburg effect is attracting increasing attention as it is important for cancer progression. However, how cancer cells regulate glucose metabolism through glycolysis is still unknown. Here, we demonstrated the regulatory role of Ras related GTP binding D (RRAGD) in human hepatocellular carcinoma (HCC) cells. PATIENTS OR MATERIALS AND METHODS: Kaplan-Meier's analysis was used to analyze the correlation between RRAGD expression levels and prognosis of HCC patients from the Cancer Genome Atlas database. Two stable RRAGD knockdown HCC cell lines were created using shRNAs to investigate cancer progression and aerobic glycolysis. Western blot and quantitative reverse transcription polymerase chain reaction were performed to detect the expression levels of RRAGD and MYC. RESULTS: RRAGD expression was elevated in HCC patients with poor prognosis. RRAGD knockdown could inhibit the proliferation, invasion and migration of Huh-7 and HepG2 cells. Interestingly, silence RRAGD was able to reduce the glucose uptake, lactate production and extracellular acidification rate of HCC. RRAGD expression level was up-regulated by oncogene MYC in HCC cells. CONCLUSION: This study highlights RRAGD as an important cancer-promoting factor for cancer progression and aerobic glycolysis, and thereby it is a potential therapeutic target for HCC intervention.
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Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Proteínas Monoméricas de Ligação ao GTP/genética , Efeito Warburg em Oncologia , Carcinoma Hepatocelular/metabolismo , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Bases de Dados Factuais , Humanos , Neoplasias Hepáticas/metabolismo , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Prognóstico , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , RNA Mensageiro/metabolismoRESUMO
Bone marrow failure (BMF) in Fanconi anemia (FA) patients results from dysfunctional hematopoietic stem and progenitor cells (HSPCs). To identify determinants of BMF, we performed single-cell transcriptome profiling of primary HSPCs from FA patients. In addition to overexpression of p53 and TGF-ß pathway genes, we identified high levels of MYC expression. We correspondingly observed coexistence of distinct HSPC subpopulations expressing high levels of TP53 or MYC in FA bone marrow (BM). Inhibiting MYC expression with the BET bromodomain inhibitor (+)-JQ1 reduced the clonogenic potential of FA patient HSPCs but rescued physiological and genotoxic stress in HSPCs from FA mice, showing that MYC promotes proliferation while increasing DNA damage. MYC-high HSPCs showed significant downregulation of cell adhesion genes, consistent with enhanced egress of FA HSPCs from bone marrow to peripheral blood. We speculate that MYC overexpression impairs HSPC function in FA patients and contributes to exhaustion in FA bone marrow.
Assuntos
Anemia de Fanconi , Animais , Medula Óssea , Dano ao DNA , Anemia de Fanconi/genética , Células-Tronco Hematopoéticas , Humanos , Camundongos , Fator de Crescimento Transformador betaRESUMO
Lithium activates Wnt/ß-catenin signaling leading to stabilization of free cytosolic ß-catenin. The aim of the present study is to evaluate the in vivo effect of acute and chronic lithium treatment on the expression of ß-catenin target genes, addressing its transcripts HIG2, Bcl-xL, Cyclin D1, c-myc, in cortical and hippocampal tissue from adult mice. Lithium doses were established to yield therapeutic working concentrations. In acute treatment, mice received a 300µL of a 350 mg/kg solution of LiCl by gavage, and were euthanized after 2 h, 6 h and 12 h. To determine the effect of chronic treatment, animals were continuously fed either with chow supplemented with 2 g/kg Li2CO3, or regular chow (controls), being euthanized after 30 days. All animals had access to drinking water and 0.9% saline ad libitum. After acute and chronic treatments samples of peripheral blood were obtained from the tail vein for each animal, and serum concentrations of lithium were determined. All transcripts were up-regulated in cortical and hippocampal tissues of lithium-treated mice, both under acute and chronic treatments. There was a positive correlation between serum lithium concentrations and the increment in the expression of all transcripts. This effect was observed in all time points of the acute treatment (i.e., 2, 6 and 12 hours) and also after 30 days. We conclude that Wnt/ß-catenin transcriptional response (HIG2, Bcl-xL, Cyclin D1 and c-myc) is up-regulated in the mouse brain in response to acute and chronic lithium treatment at therapeutic concentrations.