RESUMO
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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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.
Assuntos
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
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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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.
Assuntos
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
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.
Assuntos
Óleos Voláteis/farmacologia , Linfoma de Burkitt/tratamento farmacológico , Clausena/química , Plantas Medicinais , Óleos Voláteis/química , Linfoma de Burkitt/prevenção & controle , Apoptose/efeitos dos fármacosRESUMO
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
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.
Assuntos
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
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.
Assuntos
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
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.
Assuntos
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.