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1.
Invest New Drugs ; 42(2): 229-239, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38446332

RESUMO

SMARCA4 is a gene traditionally considered a tumor suppressor. Recent research has however found that SMARCA4 likely promotes cancer growth and is a good target for cancer treatment. The drug carbamazepine, an autophagy inducer, was used on colorectal cancer cell lines, HCT1116 and Hke3 (KRAS mutant and wildtype). Our study finds that Carbamazepine affects SMARCA4 levels and that this effect is different depending on the KRAS mutation status. This study analyzes the effect of carbamazepine on early-stage autophagy via ULK1 as well as simulates the docking of carbamazepine on KRAS, depending on the mutation status. Our study highlights the therapeutic uses of carbamazepine on cancer, and we propose that carbamazepine in conjunction with other chemotherapies may prove useful in targeting KRAS-mutated colorectal cancer.


Assuntos
Neoplasias Colorretais , Proteínas Proto-Oncogênicas p21(ras) , Humanos , Proteínas Proto-Oncogênicas p21(ras)/genética , Mutação , Linhagem Celular , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , DNA Helicases/genética , Proteínas Nucleares/genética , Fatores de Transcrição/genética
2.
Int J Mol Sci ; 24(3)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36769189

RESUMO

BRG1 is one of two catalytic subunits of the SWI/SNF ATP-dependent chromatin-remodeling complex. In cancer, it has been hypothesized that BRG1 acts as a tumor suppressor. Further study has shown that, under certain circumstances, BRG1 acts as an oncogene. Targeted knockout of BRG1 has proven successful in most cancers in suppressing tumor growth and proliferation. Furthermore, BRG1 effects cancer proliferation in oncogenic KRAS mutated cancers, with varying directionality. Thus, dissecting BRG1's interaction with various cellular pathways can highlight possible intermediates that can facilitate the design of different treatment methods, including BRG1 inhibition. Autophagy and apoptosis are two important cellular responses to stress. BRG1 plays a direct role in autophagy and apoptosis and likely promotes autophagy and suppresses apoptosis, supporting unfettered cancer growth. PRMT5 inhibits transcription by interacting with ATP-dependent chromatin remodeling complexes, such as SWI/SNF. When PRMT5 associates with the SWI/SNF complex, including BRG1, it represses tumor suppressor genes. The Ras/Raf/MAPK/ERK1/2 pathway in cancers is a signal transduction pathway involved in the transcription of genes related to cancer survival. BRG1 has been shown to effect KRAS-driven cancer growth. BRG1 associates with several proteins within the signal transduction pathway. In this review, we analyze BRG1 as a promising target for cancer inhibition and possible synergy with other cancer treatments.


Assuntos
Neoplasias , Fatores de Transcrição , Humanos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , DNA Helicases/genética , DNA Helicases/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Neoplasias/genética , Trifosfato de Adenosina , Proteína-Arginina N-Metiltransferases/metabolismo
3.
Int J Mol Sci ; 23(15)2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35955740

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a viral agent that causes Coronavirus disease 2019 (COVID-19), a disease that causes flu-like symptoms that, when exacerbated, can have life-threatening consequences. COVID-19 has been linked to persistent symptoms, sequelae, and medical complications that can last months after the initial infection. This systematic review aims to elucidate the innate and adaptive immune mechanisms involved and identify potential characteristics of COVID-19 pathology that may increase symptom duration. We also describe he three different stages of COVID-19-viral replication, immune hyperactivation, and post-acute sequelae-as well as each phase's corresponding immune response. Finally, we use this multiphasic approach to describe different treatment approaches for each of the three stages-antivirals, immunosuppressants and monoclonal antibodies, and continued immunosuppressants-to fully curate the treatment to the stage of disease.


Assuntos
Tratamento Farmacológico da COVID-19 , Antivirais/uso terapêutico , Humanos , Imunossupressores/uso terapêutico , SARS-CoV-2
4.
Mol Biol Rep ; 48(7): 5621-5627, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34196896

RESUMO

Telomeres, guanine rich DNA sequences, which are found at both ends of human chromosomes, play a vital role in genome protection. These repetitive nucleotide sequences protect the genome from nucleolytic degradation, unnecessary recombination, and interchromosomal fusion. Though, as somatic cells go through replication cycles, their telomeres shrink until they reach a critical length called the Hayflick limit. At this limit, cellular senescence, an irreversible cell cycle arrest, is prompted. For all the above reasons, telomere length is a hopeful biomarker for age-associated diseases and cancer. While there are numerous methods for telomere measurement and quantification, there are still challenges for routine analysis in clinics as these methods are not simple and rapid. Recently, a new method has been developed that measures absolute length and absolute quantities of single telomere molecules. This method, single telomere absolute-length rapid (STAR) assay, which promises to measure telomere length rapidly and accurately, is also expected to be scalable. This review will discuss different telomere length measurement methods, including STAR assay, and will highlight each of their advantages and drawbacks. It will culminate in determining if STAR assay has the potential to be the superior method for telomere measurement.


Assuntos
Testes Genéticos/métodos , Homeostase do Telômero , Telômero/genética , Instabilidade Cromossômica , Replicação do DNA , Testes Genéticos/normas , Humanos , Hibridização in Situ Fluorescente , Reação em Cadeia da Polimerase em Tempo Real , Telômero/metabolismo , Encurtamento do Telômero/genética
5.
BMC Cancer ; 20(1): 569, 2020 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-32552875

RESUMO

BACKGROUND: KRAS mutations are prevalent in 40-45% of patients with colorectal cancer (CRC) and targeting this gene has remained elusive. Viruses are well known immune sensitizing agents. The therapeutic efficacy of oncolytic reovirus in combination with chemotherapy is examined in a phase 1 study of metastatic CRC. This study evaluates the nature of immune response by determining the cytokine expression pattern in peripheral circulation along with the distribution of antigen presenting cells (APCs) and activated T lymphocytes. Further the study evaluates the alterations in exosomal and cellular microRNA levels along with the effect of reovirus on leukocyte transcriptome. METHODS: Reovirus was administered as a 60-min intravenous infusion for 5 consecutive days every 28 days, at a tissue culture infective dose (TCID50) of 3 × 1010. Peripheral blood mononuclear cells (PBMC) were isolated from whole blood prior to reovirus administration and post-reovirus on days 2, 8, and 15. The expression profile of 25 cytokines in plasma was assessed (post PBMC isolation) on an EMD Millipore multiplex Luminex platform. Exosome and cellular levels of miR-29a-3p was determined in pre and post reovirus treated samples. Peripheral blood mononuclear cells were stained with fluorophore labelled antibodies against CD4, CD8, CD56, CD70, and CD123, fixed and evaluated by flow cytometry. The expression of granzyme B was determined on core biopsy of one patient. Finally, Clariom D Assay was used to determine the expression of 847 immune-related genes when compared to pre reovirus treatment by RNA sequencing analysis. A change was considered if the expression level either doubled or halved and the significance was determined at a p value of 0.001. RESULTS: Cytokine assay indicated upregulation at day 8 for IL-12p40 (2.95; p = 0.05); day 15 for GM-CSF (3.56; p = 0.009), IFN-y (1.86; p = 0.0004) and IL-12p70 (2.42; p = 0.02). An overall reduction in IL-8, VEGF and RANTES/CCL5 was observed over the 15-day period. Statistically significant reductions were observed at Day 15 for IL-8 (0.457-fold, 53.3% reduction; p = 0.03) and RANTES/CC5 (0.524-fold, 47.6% reduction; p = 0.003). An overall increase in IL-6 was observed, with statistical significance at day 8 (1.98- fold; 98% increase, p = 0.00007). APCs were stimulated within 48 h and activated (CD8+ CD70+) T cells within 168 h as determine by flow cytometry. Sustained reductions in exosomal and cellular levels of miR-29a-3p (a microRNA upregulated in CRC and associated with decreased expression of the tumor suppressor WWOX gene) was documented. Reovirus administration further resulted in increases in KRAS (33x), IFNAR1 (20x), STAT3(5x), and TAP1 (4x) genes after 2 days; FGCR2A (23x) and CD244 (3x) after 8 days; KLRD1 (14x), TAP1 (2x) and CD244(2x) after 15 days. Reductions (> 0.5x) were observed in VEGFA (2x) after 2 days; CXCR2 (2x), ITGAM (3x) after 15 days. CONCLUSIONS: Reovirus has profound immunomodulatory properties that span the genomic, protein and immune cell distribution levels. This is the first study with reovirus in cancer patients that demonstrates these multi- layered effects, demonstrating how reovirus can function as an immune stimulant (augmenting the efficacy of immuno-chemo-therapeutic drugs), and an oncolytic agent. Reovirus thus functions bimodally as an oncolytic agent causing lysis of tumor cells, and facilitator of immune-mediated recognition and destruction of tumor cells.


Assuntos
Neoplasias Colorretais/terapia , Citocinas/metabolismo , Regulação Neoplásica da Expressão Gênica/imunologia , Terapia Viral Oncolítica/métodos , Vírus Oncolíticos/imunologia , Adulto , Células Apresentadoras de Antígenos/imunologia , Células Apresentadoras de Antígenos/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Bevacizumab/administração & dosagem , Bevacizumab/efeitos adversos , Biópsia , Camptotecina/administração & dosagem , Camptotecina/efeitos adversos , Camptotecina/análogos & derivados , Colo/imunologia , Colo/patologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Terapia Combinada/efeitos adversos , Terapia Combinada/métodos , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Perfilação da Expressão Gênica , Humanos , Infusões Intravenosas , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Leucovorina/administração & dosagem , Leucovorina/efeitos adversos , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-Idade , Mutação , Terapia Viral Oncolítica/efeitos adversos , Proteínas Proto-Oncogênicas p21(ras)/genética , Linfócitos T/imunologia , Linfócitos T/metabolismo , Resultado do Tratamento
6.
Invest New Drugs ; 37(5): 948-960, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30612311

RESUMO

Intended to explore synthetic lethality and develop better combinatorial regimens, we screened colorectal cancer (CRC) cells using poly ADP-ribose (PAR) polymerase (PARP) inhibitors and cytotoxic agents. We studied four PARP inhibitors and three DNA-damaging agents, and their combinations using sulforhodamine B assay. Rucaparib demonstrated the greatest synergy with irinotecan, followed by olaparib and PJ34. Rucaparib and irinotecan was further subjected to detailed examination to determine combination index (CI) and underlying mechanism of action. Effectiveness and sequence dependence of this combination were assessed in microsatellite stable (MSS) and unstable (MSI) CRC and HCT116 isogenic cell lines. The degree of cell cycle arrest and apoptosis was determined by FACS. In vivo studies were performed to confirm efficacy of this combination. PAR levels in MSI and PARP expression in MSI and MSS cell lines were diminished upon combinatorial treatment. HCT116 isogenic cells revealed the importance of p21, p53 and PTEN in exerting synergy. In MSI cells, administration of rucaparib prior to irinotecan enhanced cytotoxicity compared to other strategies explored. FACS revealed S-phase arrest and increased late-stage apoptosis in MSS, and G2-M arrest and total and early-stage apoptosis in MSI cells. In in vivo murine xenograft models, a significant reduction in tumor volume and expression of Ki67, pancytokeratin and RPS6KB1, and increase in expression of caspase 3 were observed with the combination. In conclusion, among the various combinations studied, rucaparib plus irinotecan was the most synergistic one. Alterations in cell cycle arrest and apoptosis were dependent on MSI status in CRC cells.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Sinergismo Farmacológico , Indóis/farmacologia , Irinotecano/farmacologia , Animais , Apoptose , Ciclo Celular , Proliferação de Células , Neoplasias Colorretais/patologia , Quimioterapia Combinada , Humanos , Camundongos , Camundongos Nus , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores da Topoisomerase I/farmacologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Int J Mol Sci ; 20(22)2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31766149

RESUMO

Patients with KRAS mutated colorectal cancer (CRC) represent a cohort with unmet medical needs, with limited options of FDA-approved therapies. Representing 40-45% of all CRC patients, they are considered ineligible to receive anti-EGFR monoclonal antibodies that have added a significant therapeutic benefit for KRAS wild type CRC patients. Although several mouse models of CRC have been developed during the past decade, one genetically resembling the KRAS mutated CRC is yet to be established. In this study C57 BL/6 mice with truncated adenomatous polyposis coli (APC) floxed allele was crossed with heterozygous KRAS floxed outbred mice to generate an APCf/f KRAS+/f mouse colony. In another set of breeding, APC floxed mice were crossed with CDX2-Cre-ERT2 mice and selected for APCf/f CDX2-Cre-ERT2 after the second round of inbreeding. The final model of the disease was generated by the cross of the two parental colonies and viable APC f/f KRAS +/f CDX2-Cre-ERT2 (KPC: APC) were genotyped and characterized. The model animals were tamoxifen (TAM) induced to generate tumors. Micro-positron emission tomography (PET) scan was used to detect and measure tumor volume and standard uptake value (SUV). Hematoxylin and eosin (H&E) staining was performed to establish neoplasm and immunohistochemistry (IHC) was performed to determine histological similarities with human FFPE biopsies. The MSI/microsatellite stable (MSS) status was determined. Finally, the tumors were extensively characterized at the molecular level to establish similarities with human CRC tumors. The model KPC: APC animals are conditional mutants that developed colonic tumors upon induction with tamoxifen in a dose-dependent manner. The tumors were confirmed to be malignant within four weeks of induction by H&E staining and higher radioactive [18F] fluoro-2-deoxyglucose (FDG) uptake (SUV) in micro-PET scan. Furthermore, the tumors histologically and molecularly resembled human colorectal carcinoma. Post tumor generation, the KPC: APC animals died of cachexia and rectal bleeding. Implications: This model is an excellent preclinical platform to molecularly characterize the KRAS mutated colorectal tumors and discern appropriate therapeutic strategies to improve disease management and overall survival.


Assuntos
Neoplasias Colorretais/genética , Mutação , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteína da Polipose Adenomatosa do Colo/genética , Animais , Fator de Transcrição CDX2/genética , Neoplasias Colorretais/patologia , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL
8.
Diseases ; 11(4)2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37873786

RESUMO

PURPOSE: To investigate the alterations in the expression of noncoding, micro, and small RNA expression during treatment with oncolytic reovirus in KRAS-mutated colorectal cancer. METHODS: Oncolytic reovirus treatment was administered in phase 1 clinical trial (NCT01274624) for 5 days every 28 days, and blood samples were collected before the administration of the reovirus and 48 h, 8 days, and 15 days after its administration on day 1. Data from the blood samples were sorted using Transcriptome Analysis Software (TAC) 4.0, where a two-tailed t-test and a fold change filter were used to ascertain which sample signals had a statistically significant relative fold change of greater than 2 at multiple timepoints before or after oncolytic reovirus administration. RESULTS: The long noncoding RNA's RP11-332M2.1 (-6.1 x), LINC01506 (-16.18 x), and LINC00534 (-1.94 x) were downregulated at 48 h after reovirus administration [p < 0.05]. ncRNA's EPB41L4A-AS1 (-6.34 x, 48 h; 11.99 x, day 8), JAK2 (2.2 x, 48 h; -2.23 x, day 8), ANXA4 (20.47 x, day 8; -7.54 x, day 15), and PCDH9 (-2.09, day 8; 1.82 x, day 15) were affected by the reovirus treatment and reflected the progress of the treatment [p < 0.05]. The small RNA SNORA26 (-1.59 x, day 8) was downregulated 48 h after the reovirus administration [p < 0.05]. The microRNA MIR-4461 (6.18 x, day 8; -3.76 x, day 15) was also affected by the reovirus administration [p < 0.05]. CONCLUSION: The administration of oncolytic reovirus to treat KRAS-mutated colorectal cancer is reflected in a noncoding RNA profile, and expression levels of the ncRNAs in that profile may thus be able to be used as a potential predictive marker for reovirus-treated colorectal cancer.

9.
Artigo em Inglês | MEDLINE | ID: mdl-37707661

RESUMO

BACKGROUND: The burden of early onset colorectal cancer (EOCRC) falls disproportionately on minorities and individuals in specific geographic regions. While these disparities are likely multi-factorial, access to high-quality health care plays a significant role. We sought to determine if Medicaid expansion is associated with reducing racial disparities in EOCRC detection in Hispanics and non-Hispanic Blacks (NHB), compared to non-Hispanic Whites (NHW). METHODS: Analysis of data from National Cancer Database was undertaken to compare incidence of EOCRC among those aged 40-49 between Medicaid expansion states (ES) and non-expansion states (NES) by racial/ethnic groups. Data was classified by race (NHW, NHB, or Hispanic), state of residence (ES or NES), and time (pre- or post-expansion). The primary outcome was change in incidence rate of EOCRC among racial/ethnic groups, according to whether patients resided in Medicaid expansion or non-expansion states. RESULTS: Among Hispanics, the ES showed a significant increase in EOCRC incidence post expansion as compared to NES (p = 0.03). The rate of increase in annual incidence of EOCRC among Hispanics was 4.3% per year (pre-expansion) and 9.8% (post-expansion) for ES; and 6.4% (pre-expansion) and 1% (post-expansion) in NES. However, no difference was noted among NHB (p = 0.33) and NHW (p = 0.94). CONCLUSIONS: Medicaid expansion has improved detection rates of EOCRC in ES especially in Hispanic population. This is the first study to demonstrate the effect of Medicaid expansion on the incidence of EOCRC. Based on our study findings we suggest that racial and ethnic disparities should be considered in the earlier CRC screening debates.

10.
J Immunol ; 185(3): 1485-91, 2010 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-20581147

RESUMO

Osteoclasts are resident cells of the bone that are primarily involved in the physiological and pathological remodeling of this tissue. Mature osteoclasts are multinucleated giant cells that are generated from the fusion of circulating precursors originating from the monocyte/macrophage lineage. During inflammatory bone conditions in vivo, de novo osteoclastogenesis is observed but it is currently unknown whether, besides increased osteoclast differentiation from undifferentiated precursors, other cell types can generate a multinucleated giant cell phenotype with bone resorbing activity. In this study, an animal model of calvaria-induced aseptic osteolysis was used to analyze possible bone resorption capabilities of dendritic cells (DCs). We determined by FACS analysis and confocal microscopy that injected GFP-labeled immature DCs were readily recruited to the site of osteolysis. Upon recruitment, the cathepsin K-positive DCs were observed in bone-resorbing pits. Additionally, chromosomal painting identified nuclei from female DCs, previously injected into a male recipient, among the nuclei of giant cells at sites of osteolysis. Finally, osteolysis was also observed upon recruitment of CD11c-GFP conventional DCs in Csf1r(-/-) mice, which exhibit a severe depletion of resident osteoclasts and tissue macrophages. Altogether, our analysis indicates that DCs may have an important role in bone resorption associated with various inflammatory diseases.


Assuntos
Reabsorção Óssea/imunologia , Reabsorção Óssea/patologia , Células Dendríticas/imunologia , Células Dendríticas/patologia , Animais , Transplante de Medula Óssea/imunologia , Transplante de Medula Óssea/patologia , Reabsorção Óssea/genética , Movimento Celular/genética , Movimento Celular/imunologia , Células Cultivadas , Modelos Animais de Doenças , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Osteoclastos/imunologia , Osteoclastos/patologia , Osteólise/imunologia , Osteólise/patologia , Receptor de Fator Estimulador de Colônias de Macrófagos/deficiência , Receptor de Fator Estimulador de Colônias de Macrófagos/genética , Crânio/imunologia , Crânio/patologia , Transdução Genética
11.
Comput Biol Med ; 141: 105110, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34920161

RESUMO

KRAS mutation is prevalent in around 30% of all cancers and is an undruggable molecular target. Of seven mutations at codon 12 and 13, only one, the G12C mutant is finally proven to be druggable, as evidenced by the recent USFDA approval of sotorasib. Investigation of other small molecules targeting G12C and G12D are undergoing clinical trials. Understanding the fine structural details is a prerequisite to design specific inhibitors which also requires in depth molecular exploration. We used bioinformatics as a tool to analyze the KRAS protein's GTP (guanosine triphosphate) binding dynamics when mutated. KRAS undergoes significant conformational changes, affecting GTP binding conformation within the active site pocket of KRAS due to high torsional strains, hydrophobicity, and altered Switch I and II regions. GTP molecule for wildtype had a low torsional strain of 10.71, and is the only molecule, in comparison to KRAS mutant bound GTP, to have a glycine at position 10 interacting with its nitrogenous base. All mutant KRAS proteins lacked the interaction of glycine with the nitrogenous base. The binding affinity of wildtype (WT) KRAS for the gamma-phosphate was lower in scoring compared to the mutated KRAS protein in multiple analyses. This study provides an insight to the GTP-KRAS protein binding details that are important to define parameters required to be explored to design the appropriate inhibitor for each different type of mutant KRAS protein.


Assuntos
Domínio AAA , Proteínas Proto-Oncogênicas p21(ras) , Códon/genética , Guanosina Trifosfato/metabolismo , Hidrólise , Mutação , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo
12.
Front Oncol ; 12: 1018767, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36387154

RESUMO

The majority of colorectal cancers (CRCs) are microsatellite stable (MSS) and resistant to immunotherapy. The current study explores the possibility of using oncolytic reovirus to sensitize MSS CRC to immune checkpoint inhibition. While reovirus reduced metabolic activity among KRAS Mut cells, microarray/computational analysis revealed microsatellite status-oriented activation of immune-response pathways. Reovirus plus anti-PD-1 treatment increased cell death among MSS cells ex vivo. Reduced tumorigenicity and proliferative index, and increased apoptosis were evident among CT26 [MSS, KRAS Mut], but not in MC38 [microsatellite unstable/MSI, KRAS Wt] syngeneic mouse models under combinatorial treatment. PD-L1-PD-1 signaling axis were differentially altered among CT26/MC38 models. Combinatorial treatment activated the innate immune system, pattern recognition receptors, and antigen presentation markers. Furthermore, we observed the reduction of immunosuppressive macrophages and expansion of effector T cell subsets, as well as reduction in T cell exhaustion. The current investigation sheds light on the immunological mechanisms of the reovirus-anti-PD-1 combination to reduce the growth of MSS CRC.

13.
Nucleic Acids Res ; 37(10): 3301-9, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19324890

RESUMO

More than one-third of the RAG1 protein can be truncated from the N-terminus with only subtle effects on the products of V(D)J recombination in vitro or in a mouse. What, then, is the function of the N-terminal domain? We believe it to be regulatory. We determined, several years ago, that an included RING motif could function as an ubiquitin E3 ligase. Whether this activity is limited to automodification, or may alter other proteins in the cell, remains an open question. We revisited the issue of additional protein-protein interactions between RAG1 and other proteins by means of the yeast two-hybrid assay. We confirmed the interaction already described with KPNA2/RCH1/SRP1alpha and found two others--to the transcription factor GMEB1/PIF p96 and the splicing factor SF3A2/SF3a66. A luciferase reporter assay demonstrates that a protein complex containing RAG proteins and the transcription factor can assemble in cells. Further mapping identified a region within the N-terminal domain resembling a WW motif. Point mutation directed at residues conserved in WW motifs eliminated binding to one of the partners. Phylogenetic analysis shows the WW-like module to be highly conserved. The module contributes to protein-protein interactions that may also influence how RAG1 binds DNA targets.


Assuntos
Proteínas de Homeodomínio/química , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Camundongos , Dados de Sequência Molecular , Mutação , Domínios e Motivos de Interação entre Proteínas , Alinhamento de Sequência , Técnicas do Sistema de Duplo-Híbrido
14.
Am J Transl Res ; 13(12): 14176-14185, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35035763

RESUMO

Reovirus is a ubiquitous, non-pathogenic, double stranded RNA virus with anti-tumor properties. The virus's replicative potential is regulated by phosphorylation of protein kinase receptor (PKR). In cancers with RAS pathway activation which leads to dysregulation of PKR, the virus maintains its protein translational potential and induces oncolysis. Systemic chemotherapy remains the standard of care for metastatic colorectal cancer with the addition of biologic agents in KRAS wildtype subtypes. In KRAS mutant colorectal cancers, there has been no added benefit to biologic agents. The therapeutic potential of reovirus (Reolysin®, pelareorep, Oncolytic Inc., Calgary, Canada), which induces its oncolysis with RAS activation through multimodal immune mechanisms, has been demonstrated in preclinical and clinical studies. In this review, we outline the specific immune mechanisms of reovirus induced oncolysis and provide both preclinical and clinical data on its applications in metastatic colorectal cancer patients.

15.
Cancers (Basel) ; 14(1)2021 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-35008242

RESUMO

Non-small cell lung cancers (NSCLCs) account for ~85% of lung cancer cases worldwide. Mammalian lungs are exposed to both endogenous and exogenous estrogens. The expression of estrogen receptors (ERs) in lung cancer cells has evoked the necessity to evaluate the role of estrogens in the disease progression. Estrogens, specifically 17ß-estradiol, promote maturation of several tissue types including lungs. Recent epidemiologic data indicate that women have a higher risk of lung adenocarcinoma, a type of NSCLC, when compared to men, independent of smoking status. Besides ERs, pulmonary tissues both in healthy physiology and in NSCLCs also express G-protein-coupled ERs (GPERs), epidermal growth factor receptor (EGFRs), estrogen-related receptors (ERRs) and orphan nuclear receptors. Premenopausal females between the ages of 15 and 50 years synthesize a large contingent of estrogens and are at a greater risk of developing NSCLCs. Estrogen-ER/GPER/EGFR/ERR-mediated activation of various cell signaling molecules regulates NSCLC cell proliferation, survival and apoptosis. This article sheds light on the most recent achievements in the elucidation of sequential biochemical events in estrogen-activated cell signaling pathways involved in NSCLC severity with insight into the mechanism of regulation by ERs/GPERs/EGFRs/ERRs. It further discusses the success of anti-estrogen therapies against NSCLCs.

16.
J Oncol Res Ther ; 6(4)2021.
Artigo em Inglês | MEDLINE | ID: mdl-34841205

RESUMO

BACKGROUND: Approximately 45% of individuals diagnosed with Colorectal Cancer (CRC) also possess KRAS mutations. One developing therapeutic method for this disease is reovirus treatment. It is theorized that reovirus treatment on patients with KRAS mutated CRC cells would be successful due to the virus' innate oncolytic properties [1]. Reovirus, a stable form of nonenveloped double-stranded RNA, causes minor infections in humans under normal circumstances. However, when the virus encounters KRAS mutated cells, it has the potential to lyse them [2]. While this method of treatment to CRC has shown signs of success, we are still some ways from universal administration of reovirus as a treatment. This review seeks to utilize various studies, as well as our original research data, to investigate reovirus as an efficient method of treatment, with a focus on select growth, apoptotic and RAS-related genes, and their effectiveness of mitigating KRAS mutated CRC post reovirus treatment. Furthermore, the review highlights transcriptome analysis as an effective tool to examine these genes and their activity. It has been shown that reovirus treatment induces apoptosis and mitigates growth related gene activity. CONCLUSIONS: This review confirms the novelty of our findings on the efficacy of reovirus in CRC treatment. The study that this review article discusses concluded that 10 apoptotic and lymphocyte-related genes were found to be upregulated and 6 angiogenesis and Ras-related genes were found to be downregulated post reovirus treatment. These findings enforce the notion that reovirus could be used as a novel treatment for KRAS mutated CRC.

17.
Cancer Manag Res ; 13: 6743-6754, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34475783

RESUMO

PURPOSE: Reovirus propagates with high efficiency in KRAS mutated colorectal cancer (CRC). About 45-50% of CRC patients possess a KRAS mutation. Oncolytic reovirus treatment in combination with chemotherapy was tested in patients possessing KRAS mutated metastatic CRC. This study evaluates the biological responses to reovirus treatment by determining the gene expression patterns in RAS-related signaling pathways. METHODS: Reovirus was administered as a 60-min intravenous infusion for 5 consecutive days every 28 days, at a tissue culture infective dose (TCID50) of 3×1010. Peripheral blood mononuclear cells (PBMCs) were isolated from whole-blood pre- and post-reovirus administration at 48 hr, day-8, and day-15. Clariom_D_Human_Assay was used to determine the expression of vital genes compared to pre-reovirus treatment by RNA sequencing. Using exported sample signals, ΔΔCt method was used to analyze the fold changes of genes within seven gene pathways. Significance was calculated by students-two-tail-t-test. Hierarchical clustering dendrogram was constructed by calculating Pearson's correlation coefficients. RESULTS: As compared to the control, SOS1[48 hr; 2.49X], RRAS [48 hr; 2.24X], PIK3CB [D8, D15; 2.27X, 3.16X], MIR 16-2 [D15; 1.70X], CHORDC1 [48 hr, D15; 1.89X, 4.54X], RTN4 [48 hr; 4.66X], FAM96A [48 hr; 4.54X], NFKB [D8, D15; 19.0X, 1.42X], CASP8 [D8, D15; 2.11X, 1.77X], and CASP9 [D8; 1.45X] are upregulated post-reovirus. NOS3 [D15; 0.61X], SYNE1 [D8, D15; 0.78X, 0.71X], ANGPT1 [D8; 0.62X], VEGFB [48 hr, D8, D15; 0.44X, 0.28X, 0.28X], JUN [D15; 0.69X], and IGF2 [D8; 0.73X] are downregulated post-reovirus. Fold change values were significant [p<0.05]. CONCLUSION: This study highlights reovirus as a novel treatment option for KRAS mutated CRC and showcases its effect on the expression of crucial genes.

18.
Cancers (Basel) ; 13(24)2021 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-34944853

RESUMO

Patients with metastatic colorectal cancer have a 5-year overall survival of less than 10%. Approximately 45% of patients with metastatic colorectal cancer harbor KRAS mutations. These mutations not only carry a predictive role for the absence of response to anti-EGFR therapy, but also have a negative prognostic impact on the overall survival. There is a growing unmet need for a personalized therapy approach for patients with KRAS-mutant colorectal cancer. In this article, we focus on the therapeutic strategies targeting KRAS- mutant CRC, while reviewing and elaborating on the discovery and physiology of KRAS.

19.
Mol Cancer Res ; 19(3): 388-394, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33288733

RESUMO

The ERK1/2 (RAS, RAF, MEK, ERK) and PI3K (PI3K, AKT, mTOR, PTEN) pathways are the chief signaling pathways for cellular proliferation, survival, and differentiation. Overactivation and hyperphosphorylation of the ERK1/2 & PI3K pathways is frequently observed in cancer and is associated with poor patient prognosis. While it is well known that genetic alterations lead to the dysregulation of the ERK1/2 & PI3K pathways, increasing evidence showcase that epigenetic alterations also play a major role in the regulation of the ERK1/2 & PI3K pathways. Protein Arginine Methyltransferase 5 (PRMT5) is a posttranslational modifier for multiple cellular processes, which is currently being tested as a therapeutic target for cancer. PRMT5 has been shown to be overexpressed in many types of cancers, as well as negatively correlated with patient survival. Numerous studies are indicating that as a posttranslational modifier, PRMT5 is extensively involved in regulating the ERK1/2 & PI3K pathways. In addition, a large number of in vitro and in vivo studies are demonstrating that PRMT5 inhibition, as well as PRMT5 and ERK1/2 & PI3K combination therapies, show significant therapeutic effects in many cancer types. In this review, we explore the vast interactions that PRMT5 has with the ERK1/2 & PI3K pathways, and we make the case for further testing of PRMT5 inhibition, as well as PRMT5 and ERK1/2 & PI3K combination therapies, for the treatment of cancer.


Assuntos
Sistema de Sinalização das MAP Quinases , Neoplasias/enzimologia , Proteína-Arginina N-Metiltransferases/antagonistas & inibidores , Animais , Linhagem Celular Tumoral , Epigênese Genética , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteína-Arginina N-Metiltransferases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo
20.
Curr Med Res Opin ; 37(2): 207-217, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33306409

RESUMO

INTRODUCTION: In December 2019, the first COVID-19 case, caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) was reported in Wuhan, China. The SARS-CoV-2 rapidly disseminated throughout the world via community spread, acquiring pandemic status with significant fatality. OBSERVATIONS: Rapid SARS-CoV-2 diagnosis was soon perceived critical for arresting community spread and effective therapy development. Human SARS-CoV-2 infection can be diagnosed either by nucleic acid identification or specific antibody detection. Contrary to nucleic acid identification confirmed active SARS-CoV-2 infection; antibody detection confirms a past infection, even in asymptomatic subjects. SARS-CoV-2 specific antibodies augment the ability to effectively counter the virus. A crucial hurdle limiting the steadfast implementation of antibody detection is the time required for threshold B lymphocyte population generation. This process is dependent on precise antigen recognition and MHC class I molecules presentation. CONCLUSIONS: Thus, nucleic acid and antibody dependent tests complement each other in identifying human SARS-CoV-2 infection and shaping up subsequent immunological responses. This article discusses the complimentary association of nucleic acid identification (corresponding to an active infection) and antibody testing (the yester CoV-2 infection vulnerability) as the diagnostic and screening measures of SARS-CoV-2 infection. Highlights Nucleic acid (RNA) identification and specific antibody detection against SARS-CoV-2 are the noted diagnostic mechanisms for screening human SARS-CoV-2 infection. While nucleic acid identification screens prevailing SARS-CoV-2 infection, detection of SARS-CoV-2 specific antibodies signifies a past infection, even in asymptomatic subjects. Antibodies against SARS-CoV-2 provide a potential therapeutic option via transfer from antibody rich plasma of a recovered subject to an infected individual. Nucleic acid identification may not absolutely confirm the infection because of frequent SARS-CoV-2 genome mutations and possible technical errors, while specific antibody detection also needs at least (8-14) days for detectable screening of B-cell generated antibodies. Nucleic acid and antibody tests are complementary to each other as an early stage diagnostic assay for SARS-CoV-2 infection and possible therapy (antibodies). Sufferers with a high clinical suspicion but negative RT-PCR screening could be examined via combined imaging and repeated swab test.


Assuntos
Teste de Ácido Nucleico para COVID-19/métodos , Teste Sorológico para COVID-19/métodos , COVID-19/diagnóstico , COVID-19/imunologia , Teste para COVID-19 , Aprovação de Teste para Diagnóstico , Ensaio de Imunoadsorção Enzimática , Humanos , Medições Luminescentes , Programas de Rastreamento , Testes de Neutralização , Pandemias , RNA Viral/isolamento & purificação , SARS-CoV-2/genética , SARS-CoV-2/imunologia
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