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1.
Clin Immunol ; 263: 110204, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38582251

RESUMO

BACKGROUND: T-ALL is an aggressive hematological tumor that develops as the result of a multi-step oncogenic process which causes expansion of hematopoietic progenitors that are primed for T cell development to undergo malignant transformation and growth. Even though first-line therapy has a significant response rate, 40% of adult patients and 20% of pediatric patients will relapse. Therefore, there is an unmet need for treatment for relapsed/refractory T-ALL to develop potential targeted therapies. METHODS: Pediatric T-ALL patient derived T cells were grown under either nonskewingTh0 or Th1-skewing conditions to further process for ChIP-qPCR, RDIP-qPCR and other RT-PCR assays. Endogenous WASp was knocked out using CRISPR-Cas9 and was confirmed using flow cytometry and western blotting. LC-MS/MS was performed to find out proteomic dataset of WASp-interactors generated from Th1-skewed, human primary Th-cells. DNA-damage was assessed by immunofluorescence confocal-imaging and single-cell gel electrophoresis (comet assay). Overexpression of RNaseH1 was also done to restore normal Th1-transcription in WASp-deficient Th1-skewed cells. RESULTS: We discovered that nuclear-WASp is required for suppressing R-loop production (RNA/DNA-hybrids) at Th1-network genes by ribonucleaseH2 (RNH2) and topoisomerase1. Nuclear-WASp is associated with the factors involved in preventing and dissolving R-loops in Th1 cells. In nuclear- WASp-reduced malignant Th1-cells, R-loops accumulate in vivo and are processed into DNA-breaks by transcription-coupled-nucleotide-excision repair (TC-NER). Several epigenetic modifications were also found to be involved at Th1 gene locus which are responsible for active/repressive marks of particular genes. By demonstrating WASp as a physiologic regulator of programmed versus unprogrammed R-loops, we suggest that the transcriptional role of WASp in vivo extends also to prevent transcription-linked DNA damage during malignancy and through modification of epigenetic dysregulations. CONCLUSION: Our findings present a provocative possibility of resetting R-loops as a therapeutic intervention to correct both immune deficiency and malignancy in T-cell acute lymphoblastic leukemia patients and a novel role of WASp in the epigenetic regulation of T helper cell differentiation in T-ALL patients, anticipating WASp's requirement for the suppression of T-ALL progression.


Assuntos
Reparo por Excisão , Instabilidade Genômica , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Células Th1 , Proteína da Síndrome de Wiskott-Aldrich , Criança , Humanos , Dano ao DNA , Instabilidade Genômica/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/imunologia , Células Th1/imunologia , Transcrição Gênica , Proteína da Síndrome de Wiskott-Aldrich/genética
2.
Mol Biol Rep ; 50(12): 10383-10398, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37840067

RESUMO

A major global health burden continues to be borne by the complex and multifaceted disease of cancer. Epigenetic changes, which are essential for the emergence and spread of cancer, have drawn a huge amount of attention recently. The CCCTC-binding factor (CTCF), which takes part in a wide range of cellular processes including genomic imprinting, X chromosome inactivation, 3D chromatin architecture, local modifications of histone, and RNA polymerase II-mediated gene transcription, stands out among the diverse array of epigenetic regulators. CTCF not only functions as an architectural protein but also modulates DNA methylation and histone modifications. Epigenetic regulation of cancer has already been the focus of plenty of studies. Understanding the role of CTCF in the cancer epigenetic landscape may lead to the development of novel targeted therapeutic strategies for cancer. CTCF has already earned its status as a tumor suppressor gene by acting like a homeostatic regulator of genome integrity and function. Moreover, CTCF has a direct effect on many important transcriptional regulators that control the cell cycle, apoptosis, senescence, and differentiation. As we learn more about CTCF-mediated epigenetic modifications and transcriptional regulations, the possibility of utilizing CTCF as a diagnostic marker and therapeutic target for cancer will also increase. Thus, the current review intends to promote personalized and precision-based therapeutics for cancer patients by shedding light on the complex interplay between CTCF and epigenetic processes.


Assuntos
Fator de Ligação a CCCTC , Epigênese Genética , Neoplasias , Humanos , Fator de Ligação a CCCTC/genética , Fator de Ligação a CCCTC/metabolismo , Metilação de DNA/genética , Epigênese Genética/genética , Neoplasias/genética , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo
3.
Mol Biol Rep ; 49(8): 7995-8006, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35596054

RESUMO

Several proteins are involved in DNA repair mechanisms attempting to repair damages to the DNA continuously. One such protein is Xeroderma Pigmentosum Complementation Group G (XPG), a significant component in the Nucleotide Excision Repair (NER) pathway. XPG is accountable for making the 3' incision in the NER, while XPF-ERCC4 joins ERCC1 to form the XPF-ERCC1 complex. This complex makes a 5' incision to eliminate bulky DNA lesions. XPG is also known to function as a cofactor in the Base Excision Repair (BER) pathway by increasing hNth1 activity, apart from its crucial involvement in the NER. Reports suggest that XPG also plays a non-catalytic role in the Homologous Recombination Repair (HRR) pathway by forming higher-order complexes with BRCA1, BRCA2, Rad51, and PALB2, further influencing the activity of these molecules. Studies show that, apart from its vital role in repairing DNA damages, XPG is also responsible for R-loop formation, which facilitates exhibiting phenotypes of Werner Syndrome. Though XPG has a role in several DNA repair pathways and molecular mechanisms, it is primarily a NER protein. Unrepaired and prolonged DNA damage leads to genomic instability and facilitates neurological disorders, aging, pigmentation, and cancer susceptibility. This review explores the vital role of XPG in different DNA repair mechanisms which are continuously involved in repairing these damaged sites and its failure leading to XP-G, XP-G/CS complex phenotypes, and cancer progression.


Assuntos
Endonucleases , Fatores de Transcrição , DNA/metabolismo , Dano ao DNA/genética , Reparo do DNA/genética , Endonucleases/genética , Proteínas Nucleares/genética , Fatores de Transcrição/genética , Xeroderma Pigmentoso
4.
J Allergy Clin Immunol ; 142(1): 219-234, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29248492

RESUMO

BACKGROUND: Wiskott-Aldrich syndrome (WAS), X-linked thrombocytopenia (XLT), and X-linked neutropenia, which are caused by WAS mutations affecting Wiskott-Aldrich syndrome protein (WASp) expression or activity, manifest in immunodeficiency, autoimmunity, genomic instability, and lymphoid and other cancers. WASp supports filamentous actin formation in the cytoplasm and gene transcription in the nucleus. Although the genetic basis for XLT/WAS has been clarified, the relationships between mutant forms of WASp and the diverse features of these disorders remain ill-defined. OBJECTIVE: We sought to define how dysfunctional gene transcription is causally linked to the degree of TH cell deficiency and genomic instability in the XLT/WAS clinical spectrum. METHODS: In human TH1- or TH2-skewing cell culture systems, cotranscriptional R-loops (RNA/DNA duplex and displaced single-stranded DNA) and DNA double-strand breaks (DSBs) were monitored in multiple samples from patients with XLT and WAS and in normal T cells depleted of WASp. RESULTS: WASp deficiency provokes increased R-loops and R-loop-mediated DSBs in TH1 cells relative to TH2 cells. Mechanistically, chromatin occupancy of serine 2-unphosphorylated RNA polymerase II is increased, and that of topoisomerase 1, an R-loop preventing factor, is decreased at R-loop-enriched regions of IFNG and TBX21 (TH1 genes) in TH1 cells. These aberrations accompany increased unspliced (intron-retained) and decreased spliced mRNA of IFNG and TBX21 but not IL13 (TH2 gene). Significantly, increased cellular load of R-loops and DSBs, which are normalized on RNaseH1-mediated suppression of ectopic R-loops, inversely correlates with disease severity scores. CONCLUSION: Transcriptional R-loop imbalance is a novel molecular defect causative in TH1 immunodeficiency and genomic instability in patients with WAS. The study proposes that cellular R-loop load could be used as a potential biomarker for monitoring symptom severity and prognostic outcome in the XLT-WAS clinical spectrum and could be targeted therapeutically.


Assuntos
Instabilidade Genômica/genética , Células Th1/patologia , Síndrome de Wiskott-Aldrich/genética , Células Cultivadas , Dano ao DNA/genética , Humanos , Transcrição Gênica , Síndrome de Wiskott-Aldrich/patologia
5.
Blood ; 126(14): 1670-82, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26261240

RESUMO

In Wiskott-Aldrich syndrome (WAS), immunodeficiency and autoimmunity often comanifest, yet how WAS mutations misregulate chromatin-signaling in Thelper (TH) cells favoring development of auto-inflammation over protective immunity is unclear. Previously, we identified an essential promoter-specific, coactivator role of nuclear-WASp in TH1 gene transcription. Here we identify small ubiquitin-related modifier (SUMO)ylation as a novel posttranslational modification of WASp, impairment of which converts nuclear-WASp from a transcriptional coactivator to a corepressor of nuclear factor (NF)-κB response genes in human (TH)1-differentiating cells. V75M, one of many disease-causing mutations occurring in SUMO*motif (72-ψψψψKDxxxxSY-83) of WASp, compromises WASp-SUMOylation, associates with COMMD1 to attenuate NF-κB signaling, and recruits histone deacetylases-6 (HDAC6) to p300-marked promoters of NF-κB response genes that pattern immunity but not inflammation. Consequently, proteins mediating adaptive immunity (IFNG, STAT1, TLR1) are deficient, whereas those mediating auto-inflammation (GM-CSF, TNFAIP2, IL-1ß) are paradoxically increased in TH1 cells expressing SUMOylation-deficient WASp. Moreover, SUMOylation-deficient WASp favors ectopic development of the TH17-like phenotype (↑IL17A, IL21, IL22, IL23R, RORC, and CSF2) under TH1-skewing conditions, suggesting a role for WASp in modulating TH1/TH17 plasticity. Notably, pan-histone deacetylase inhibitors lift promoter-specific repression imposed by SUMOylation-deficient WASp and restore misregulated gene expression. Our findings uncovering a SUMOylation-based mechanism controlling WASp's dichotomous roles in transcription may have implications for personalized therapy for patients carrying mutations that perturb WASp-SUMOylation.


Assuntos
Regulação da Expressão Gênica/imunologia , Mutação , NF-kappa B/imunologia , Células Th1/imunologia , Ativação Transcricional/fisiologia , Proteína da Síndrome de Wiskott-Aldrich/genética , Imunidade Adaptativa/genética , Imunidade Adaptativa/imunologia , Western Blotting , Linhagem Celular , Ensaio de Desvio de Mobilidade Eletroforética , Citometria de Fluxo , Humanos , Imunoprecipitação , Espectrometria de Massas , Mutagênese Sítio-Dirigida , NF-kappa B/genética , Reação em Cadeia da Polimerase , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Sumoilação , Transfecção
7.
Int J Cancer ; 139(9): 2068-81, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27405489

RESUMO

Mesenchymal stem cells (MSCs) represent an important cellular constituent of the tumor microenvironment, which along with tumor cells themselves, serve to regulate protective immune responses in support of progressive disease. We report that tumor MSCs prevent the ability of dendritic cells (DC) to promote naïve CD4(+) and CD8(+) T cell expansion, interferon gamma secretion and cytotoxicity against tumor cells, which are critical to immune-mediated tumor eradication. Notably, tumor MSCs fail to prevent DC-mediated early T cell activation events or the ability of responder T cells to produce IL-2. The immunoregulatory activity of tumor MSCs is IL-10- and STAT3-dependent, with STAT3 repressing DC expression of cystathionase, a critical enzyme that converts methionine-to-cysteine. Under cysteine-deficient priming conditions, naïve T cells exhibit defective cellular metabolism and proliferation. Bioinformatics analyses as well as in vitro observations suggest that STAT3 may directly bind to a GAS-like motif within the cystathionase promoter (-269 to -261) leading to IL-10-STAT3 mediated repression of cystathionase gene transcription. Our collective results provide evidence for a novel mechanism of tumor MSC-mediated T cell inhibition within tumor microenvironment.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Cisteína/metabolismo , Células Dendríticas/metabolismo , Células-Tronco Mesenquimais/patologia , Animais , Diferenciação Celular , Linhagem Celular , Proliferação de Células , Feminino , Humanos , Interferon gama/metabolismo , Interleucina-10/metabolismo , Interleucina-2/metabolismo , Ativação Linfocitária , Células-Tronco Mesenquimais/citologia , Camundongos , Fator de Transcrição STAT3
8.
Blood ; 124(23): 3409-19, 2014 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-25253772

RESUMO

Wiskott-Aldrich syndrome (WAS), an immunodeficiency disorder, and X-linked thrombocytopenia (XLT), a bleeding disorder, both arise from nonsynonymous mutations in WAS, which encodes a hematopoietic-specific WASp. Intriguingly, XLT evolves into WAS in some patients but not in others; yet the biological basis for this cross-phenotype (CP) effect remains unclear. Using human T-helper (TH) cells expressing different disease-causing WAS mutations, we demonstrated that hSWI/SNF-like complexes require nuclear-WASp to execute their chromatin-remodeling activity at promoters of WASp-target, immune function genes during TH1 differentiation. Hot-spot WAS mutations Thr45Met and Arg86Cys, which result in XLT-to-WAS disease progression, impair recruitment of hBRM- but not BRG1-enriched BAF complexes to IFNG and TBX21 promoters. Moreover, promoter enrichment of histone H2A.Z and its catalyzing enzyme EP400 are both impaired. Consequently, activation of Notch signaling, a hBRM-regulated event, and its downstream effector NF-κB are both compromised, along with decreased accessibility of nucleosomal DNA and inefficient transcription-elongation of WASp-target TH1 genes. In contrast, patient mutations Ala236Gly and Arg477Lys that manifest in XLT without progressing to WAS do not disrupt chromatin remodeling or transcriptional reprogramming of TH1 genes. Our study defines an indispensable relationship between nuclear-WASp- and hSWI/SNF-complexes in gene activation and reveals molecular distinctions in TH cells that might contribute to disease severity in the XLT/WAS clinical spectrum.


Assuntos
Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/metabolismo , Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico , Linfócitos T/metabolismo , Trombocitopenia/diagnóstico , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteína da Síndrome de Wiskott-Aldrich/genética , Síndrome de Wiskott-Aldrich/diagnóstico , Núcleo Celular/genética , Células Cultivadas , Diagnóstico Diferencial , Doenças Genéticas Ligadas ao Cromossomo X/genética , Humanos , Mutação , Regiões Promotoras Genéticas , Células Th1/metabolismo , Trombocitopenia/genética , Síndrome de Wiskott-Aldrich/genética , Proteína da Síndrome de Wiskott-Aldrich/metabolismo
9.
J Immunol ; 193(1): 150-60, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24872192

RESUMO

Defects in Wiskott-Aldrich Syndrome protein (WASp) underlie development of WAS, an X-linked immunodeficiency and autoimmunity disorder of childhood. Nucleation-promoting factors (NPFs) of the WASp family generate F-actin in the cytosol via the VCA (verprolin-homology, cofilin-homology, and acidic) domain and support RNA polymerase II-dependent transcription in the nucleus. Whether nuclear-WASp requires the integration of its actin-related protein (ARP)2/3-dependent cytoplasmic function to reprogram gene transcription, however, remains unresolved. Using the model of human TH cell differentiation, we find that WASp has a functional nuclear localizing and nuclear exit sequences, and accordingly, its effects on transcription are controlled mainly at the level of its nuclear entry and exit via the nuclear pore. Human WASp does not use its VCA-dependent, ARP2/3-driven, cytoplasmic effector mechanisms to support histone H3K4 methyltransferase activity in the nucleus of TH1-skewed cells. Accordingly, an isolated deficiency of nuclear-WASp is sufficient to impair the transcriptional reprogramming of TBX21 and IFNG promoters in TH1-skewed cells, whereas an isolated deficiency of cytosolic-WASp does not impair this process. In contrast, nuclear presence of WASp in TH2-skewed cells is small, and its loss does not impair transcriptional reprogramming of GATA3 and IL4 promoters. Our study unveils an ARP2/3:VCA-independent function of nuclear-WASp in TH1 gene activation that is uncoupled from its cytoplasmic role in actin polymerization.


Assuntos
Complexo 2-3 de Proteínas Relacionadas à Actina/imunologia , Actinas/imunologia , Núcleo Celular/imunologia , Células Th1/imunologia , Células Th2/imunologia , Transcrição Gênica/imunologia , Proteína da Síndrome de Wiskott-Aldrich/imunologia , Complexo 2-3 de Proteínas Relacionadas à Actina/genética , Actinas/genética , Núcleo Celular/genética , Fator de Transcrição GATA3/genética , Fator de Transcrição GATA3/imunologia , Células HeLa , Histona Metiltransferases , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/imunologia , Humanos , Interferon gama/genética , Interferon gama/imunologia , Interleucina-4/genética , Interleucina-4/imunologia , Células Jurkat , Proteínas com Domínio T/genética , Proteínas com Domínio T/imunologia , Transcrição Gênica/genética , Proteína da Síndrome de Wiskott-Aldrich/genética
10.
Pathol Res Pract ; 255: 155169, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38330617

RESUMO

Even though their effector roles extend beyond conventional humoral immunity, B and plasma cells may exhibit antitumor effects through antibody-dependent cell cytotoxicity (ADCC) and activation of the complement cascade. Depending on whether they are positioned in immature or mature compartments termed tertiary lymphoid structures (TLS), which include T cells, B cells are believed to play numerous functions in modulating the immune system's capacity to destroy cancer cells. These formations represent a process of lymphoid neogenesis that takes place in peripheral tissues in response to prolonged exposure to inflammatory signals. Activated in the germinal centres of tertiary lymphoid structures, B cells may directly present tumor-associated antigens to T cells, make antibodies that enhance antigen presentation to T cells, or kill tumour cells, resulting in a favourable therapeutic effect. Immune complexes may also enhance inflammation, angiogenesis, and immunosuppression via the activation of macrophages and complement, resulting in detrimental effects. The functional variety of B-cell subsets includes professional antigen-presenting cells, regulatory cells, memory populations, and plasma cells that produce antibodies. Importantly, antibodies may independently generate innate immune responses and the cancer immunity cycle. B cells and B-cell-mediated antibody responses constitute the largely underestimated second arm of the adaptive immune system and unquestionably need more consideration in cancer. This article reviews the known roles of B lymphocytes in the tumour microenvironment, their contribution to anticancer activity of immunotherapies, and their significance in overall survival of cancer patients. In addition to producing antibodies, B cells regulate the immune system and serve as effective antigen-presenting cells.


Assuntos
Neoplasias , Estruturas Linfoides Terciárias , Humanos , Linfócitos B/patologia , Neoplasias/patologia , Linfócitos T/patologia , Anticorpos , Imunoterapia/métodos , Microambiente Tumoral
11.
ACS Appl Bio Mater ; 7(5): 3388-3402, 2024 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-38660938

RESUMO

In the present investigation, natural bone-derived hydroxyapatite (HA, 2 wt %) and/or exfoliated graphene (Gr, 0.1 wt %)-embedded polydimethylsiloxane (PDMS) elastomeric films were prepared using a vascular method. The morphology, mechanical properties, crystallinity, and chemical structure of the composite films were evaluated. The in vitro biodegradation kinetics of the films indicates their adequate physiological stability. Most of the results favored PDMS/HA/Gr as a best composite scaffold having more than 703% elongation. A simulation study of the microfluidic vascular channel of the PDMS/HA/Gr scaffold suggests that the pressure drop at the outlet became greater (from 1.19 to 0.067 Pa) unlike velocity output (from 0.071 to 0.089 m/s), suggesting a turbulence-free laminar flow. Our bioactive scaffold material, PDMS/HA/Gr, showed highest cytotoxicity toward the lung cancer and breast cancer cells through Runx3 protein-mediated cytotoxic T lymphocyte (CTL) generation. Our data and predicted mechanism also suggested that the PDMS/HA/Gr-supported peripheral blood mononuclear cells (PBMCs) not only increased the generation of CTL but also upregulated the expression of RUNX3. Since the PDMS/HA/Gr scaffold-supported Runx3 induced CTL generation caused maximum cell cytotoxicity of breast cancer (MCF-7) and lung cancer (A549) cells, PDMS/HA/Gr can be treated as an excellent potential candidate for CTL-mediated cancer therapy.


Assuntos
Materiais Biocompatíveis , Dimetilpolisiloxanos , Durapatita , Grafite , Teste de Materiais , Nanocompostos , Alicerces Teciduais , Durapatita/química , Durapatita/farmacologia , Grafite/química , Grafite/farmacologia , Humanos , Dimetilpolisiloxanos/química , Nanocompostos/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Alicerces Teciduais/química , Tamanho da Partícula , Carcinogênese/efeitos dos fármacos , Antineoplásicos/farmacologia , Antineoplásicos/química , Sobrevivência Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos
12.
Pathol Res Pract ; 253: 155026, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38118219

RESUMO

As patients continue to suffer from lymphoproliferative and myeloproliferative diseases known as haematopoietic malignancies can affect the bone marrow, blood, lymph nodes, and lymphatic and non-lymphatic organs. Despite advances in the current treatment, there is still a significant challenge for physicians to improve the therapy of HMs. WASp is an important regulator of actin polymerization and the involvement of WASp in transcription is thought to be linked to the DNA damage response and repair. In some studies, severe immunodeficiency and lymphoid malignancy are caused by WASp mutations or the absence of WASp and these mutations in WAS can alter the function and/or expression of the intracellular protein. Loss-of-function and Gain-of-function mutations in WASp have an impact on cancer malignancies' incidence and onset. Recent studies suggest that depending on the clinical or experimental situation, WASPs and WAVEs can operate as a suppressor or enhancers for cancer malignancy. These dual functions of WASPs and WAVEs in cancer likely arose from their multifaceted role in cells that could be targeted for anticancer drug development. The significant role and their association of WASp in Chronic myeloid leukaemia, Juvenile myelomonocytic leukaemia and T-cell lymphoma is discussed. In this review, we described the structure and function of WASp and its family mechanism, analysing major regulatory effectors and summarising the clinical relevance and drugs that specifically target WASp in disease treatment in various hematopoietic malignancies by different approaches.


Assuntos
Neoplasias Hematológicas , Neoplasias , Síndrome de Wiskott-Aldrich , Humanos , Proteína da Síndrome de Wiskott-Aldrich/genética , Proteína da Síndrome de Wiskott-Aldrich/metabolismo , Síndrome de Wiskott-Aldrich/genética , Síndrome de Wiskott-Aldrich/metabolismo , Síndrome de Wiskott-Aldrich/terapia , Neoplasias Hematológicas/genética , Biologia Molecular , Actinas/metabolismo
13.
Med Oncol ; 41(5): 115, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622289

RESUMO

Bacopa monnieri (L) Wettst, commonly known as Brahmi, stands as a medicinal plant integral to India's traditional medical system, Ayurveda, where it is recognized as a "medhya rasayana"-a botanical entity believed to enhance intellect and mental clarity. Its significant role in numerous Ayurvedic formulations designed to address conditions such as anxiety, memory loss, impaired cognition, and diminished concentration underscores its prominence. Beyond its application in cognitive health, Brahmi has historically been employed in Ayurvedic practices for the treatment of inflammatory diseases, including arthritis. In contemporary biomedical research, Bacopa monnieri can attenuate the release of pro-inflammatory cytokines TNF-α and IL-6 in animal models. However, there remains a paucity of information regarding Bacopa's potential as an anticancer agent, warranting further investigation in this domain. Based on previous findings with Brahmi (Bacopa monnieri), the current study aims to find out the role of Brahmi plant preparation (BPP) in immunomodulatory actions on IDC. Employing a specific BPP concentration, we conducted a comprehensive study using MTT assay, ELISA, DNA methylation analysis, Western blotting, ChIP, and mRNA profiling to assess BPP's immunomodulatory properties. Our research finding showed the role of BPP in augmenting the action of T helper 1 (TH1) cells which secreted interferon-γ (IFN-γ) which in turn activated cytotoxic T-lymphocytes (CTL) to kill the cells of IDC (*p < 0.05). Moreover, we found out that treatment with BPP not only increased the activities of tumor-suppressor genes (p53 and BRCA1) but also decreased the activities of oncogenes (Notch1 and DNAPKcs) in IDC (*p < 0.05). BPP had an immense significance in controlling the epigenetic dysregulation in IDC through the downregulation of Histone demethylation & Histone deacetylation and upregulation of Histone methylation and Histone acetylation (*p < 0.05). Our Chromatin immunoprecipitation (ChIP)-qPCR data showed BPP treatment increased percentage enrichment of STAT1 & BRCA1 (*p < 0.05) and decreased percentage enrichment of STAT3, STAT5 & NF ΚB (*p < 0.05) on both TBX21 and BRCA1 gene loci in IDC. In addition, BPP treatment reduced the hypermethylation of the BRCA1-associated-DNA, which is believed to be a major factor in IDC (*p < 0.05). BPP not only escalates the secretion of type 1 specific cytokines but also escalates tumor suppression and harmonizes various epigenetic regulators and transcription factors associated with Signal Transducer and Activator of Transcription (STAT) to evoke tumor protective immunity in IDC.


Assuntos
Bacopa , Carcinoma Ductal , Neoplasias , Animais , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Histonas , Citocinas
14.
Pathol Res Pract ; 262: 155534, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39180801

RESUMO

T cells are essential to the immune system's reaction. The major job of the immune system is to identify and get rid of any abnormal or malignant cells in the body. White blood cells called T cells coordinate and carry out immunological responses, including identifying and eliminating cancer cells. It mostly consists of two types called helper T-cells and cytotoxic T-cells. Together, they create an efficient reaction against cancer. Both the primary T cell subtype - CD4+ and CD8+ Tcells have specific role to play in our immune system.CD4+ T cells are limited to MHC-II molecules and acts as helper cell by activating and enhancing other immune cells. On the other side CD8+ T cells are called the killer cells as they eradicate the abnormal and contaminated cells and are limited to MHC-I molecules. The malignant cells are destroyed when cytotoxic T cells come into direct contact with them. This happens via number of processes, including TCR recognition, the release of cytotoxic chemicals, and finally the activation of the immune system. T cell receptors on the surface of cytotoxic T cells allow them to identify tumour cells and these T cells release harmful chemicals like perforins and granzymes when they connect to malignant cells. T-cells that have been stimulated release cytokines such as gamma interferon. T-cells can also acquire memory responses that improve their capacity for recognition and response. Helper T-cells contribute to the development of an immune response. It entails coordination and activation as well as the enlistment of additional immune cells, including macrophages and natural killer cells, to assist in the eradication of cancer cells. Despite the fact that the cancer frequently creates defence systems to circumvent their immune response. Together, these activities support the immune surveillance and T-cell-mediated regulation of cancer cells. Treatments like chemotherapy, radiation, and surgery are main ways to treat cancer but immunotherapy has been emerging since last few decades. These immune specific treatments have shown huge positive result. CAR T cell therapy is a promising weapon to fight again blood cancer and it works by focusing on our immune system to fight and eliminate cancer.


Assuntos
Neoplasias , Humanos , Neoplasias/imunologia , Linfócitos T Citotóxicos/imunologia , Animais
15.
Pathol Res Pract ; 261: 155485, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39088877

RESUMO

Numerous developments have been achieved in the study and treatment of cancer throughout the decades that it has been common. After decades of research, about 100 different kinds of cancer have been found, each with unique subgroups within certain organs. This has significantly expanded our understanding of the illness. A mix of genetic, environmental, and behavioral variables contribute to the complicated and diverse process of cancer formation. Mutations, or changes in the DNA sequence, are crucial to the development of cancer. These mutations have the ability to downregulate the expression and function of Major Histocompatibility Complex class I (MHC I) and MHCII receptors, as well as activate oncogenes and inactivate tumor suppressor genes. Cancer cells use this tactic to avoid being recognized by cytotoxic CD8+T lymphocytes, which causes issues with antigen presentation and processing. This review goes into great length into the PI3K pathway, changes to MHC I, and positive impacts of tsMHC-II on disease-free survival and overall survival and the involvement of dendritic cells (DCs) in different tumor microenvironments. The vital functions that the PI3K pathway and its link to the mTOR pathway are highlighted and difficulties in developing effective cancer targeted therapies and feedback systems has also been mentioned, where resistance mechanisms include RAS-mediated oncogenic changes and active PI3K signalling.


Assuntos
Apresentação de Antígeno , Carcinogênese , Neoplasias , Transdução de Sinais , Humanos , Neoplasias/imunologia , Neoplasias/patologia , Apresentação de Antígeno/imunologia , Carcinogênese/imunologia , Carcinogênese/genética , Microambiente Tumoral/imunologia , Antígenos de Neoplasias/imunologia , Antígenos de Neoplasias/metabolismo , Animais , Fosfatidilinositol 3-Quinases/metabolismo
16.
Pathol Res Pract ; 253: 155004, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38086291

RESUMO

BACKGROUND: NSCLC is one of the leading causes of death and is often diagnosed at late stages with no alternative therapeutic approach. DCs are professional antigen-presenting cells and DC-based immunotherapy has been under the spotlight for its anti-cancer properties. Epigenetic modifications including DNA methylation and histone modification in DCs play a crucial role in regulating their functions such as maturation and activation,innate immune responses, T cell priming, antigen presentation, and cytokine production. In the current study, we investigated the anti-cancer properties of Doxorubicin at a noncytotoxic concentration that could be extrapolated as an epigenetic regulator for DC maturation to elicit anti-tumor activity. METHODOLOGIES: PBMCs from normal and NSCLC blood samples were isolated and treated with growth factors. DCs were matured with low dose Doxorubicin and the DC maturation markers were checked by using flow-cytometry. Further, ELISA was performed and low dose Doxorubicin-induced DCs were pulsed with LCA (Lung Cancer Antigen) and primed with CD4 +T helper (Th) cells for cytotoxicity assessment. Further, epigenetic markers of T: DC conjugation were immunofluorescently visualized under a microscope. ChIP-qPCR and Invitro assays such as histone methylation, DNA methylation, and m6A methylation were performed to study the epigenetic changes under low dose Dox treatment. IL-12 neutralization assay was performed to check for the IL-12 dependency of DCs and their effect under Dox at low dose treatment. This was further followed by a Western Blotting analysis for histone and non-histone proteins. RESULTS: Low dose Doxorubicin induces epigenetic changes in DCs to elicit an anti-tumor response in NSCLC through the generation of CTLs with a concomitant increase in the extracellular secretions of anti-inflammatory cytokines. We also found that low dosage of Doxorubicin matured DCs when pulsed with LCA and primed with CD4 +T helper cells, secrete IFN-γ which is important in orchestrating adaptive immunity by activating CD8 + cytotoxic T-lymphocytes. Also, the secretions of IL-12 help us infer that protective immunity is also induced via Th1 response which triggered selectively the translocation of PKCθ to immunological synapse in between DC and Th. Further, methylation and acetylation markers H3K4me3 and H3K14Ac respectively upregulated whereas levels of STAT5, NFkB, NOTCH1, and DNAPKcs were downregulated. DNA and RNA methylation assays then lead to confirmations about the epigenetic changes caused by low dose Dox treatment. DNA methylation was reduced which resulted in the activation of tumor suppressor gene p53 and Th1-associated transcription factor TBX21. On the other hand, both absolute and relative RNA methylation quantification increased in the presence of Dox at a low dose. CONCLUSION: From this study, we understand that non-cytotoxic concentration of Doxorubicin increases the Ag-presenting ability of DCs via an IL-12-dependent mechanism and causes epigenetic modifications in NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Histonas/metabolismo , Neoplasias Pulmonares/metabolismo , Epigênese Genética , Células Dendríticas , Citocinas/metabolismo , Interleucina-12/metabolismo , Ativação Linfocitária , Doxorrubicina/farmacologia , Doxorrubicina/metabolismo
17.
Med Oncol ; 41(5): 107, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38580762

RESUMO

Diospyros peregrina is a dioecious plant which is native to India. It belongs to the family of Ebenaceae and is extensively used to treat various ailments, such as leucorrhoea and other uterine-related problems. Though few studies have been on D. peregrina for their anti-tumour response, little is known. Therefore, this intrigued us to understand its immunomodulator capabilities on various types of cancer extensively. Our primary focus is on NSCLC (Non-Small Cell Lung Cancer), which is ranked as the second largest form of cancer in the world, and the treatments demand non-invasive agents to target NSCLC effectively. In an objective to generate an efficient Lung Cancer Associated Antigen (LCA) specific anti-tumour immune response, LCA was presented using dendritic cells (DCs) in the presence of D. peregrina fruit preparation (DFP). Moreover, we also investigated DFP's role in the differentiation of T-helper (TH) cells. Therefore, this study aimed at better LCA presentation mediated by DFP by activating the LCA pulsed DCs and T helper cell differentiation for better immune response. DCs were pulsed with LCA for tumour antigen presentation in vitro, with and without DFP. Differentially pulsed DCs were irradiated to co-culture with autologous and allogeneic lymphocytes. Extracellular supernatants were collected for the estimation of cytokine levels by ELISA. LDH release assay was performed to test Cytotoxic T lymphocytes (CTLs) mediated lung tumour cell cytotoxicity. Thus, DFP may be a potential vaccine to generate anti-LCA immune responses to restrict NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Diospyros , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/metabolismo , Apresentação de Antígeno , Frutas , Células Dendríticas , Linfócitos T Citotóxicos , Diferenciação Celular
18.
Int Immunopharmacol ; 122: 110661, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37473712

RESUMO

Histone deacetylases (HDACs) play a crucial role in the epigenetic regulation of gene expression by remodelling chromatin. Isoenzymes of the HDAC family exhibit aberrant regulation in a wide variety of cancers as well as several inflammatory lung disorders like chronic obstructive pulmonary disease (COPD). Inhibition of HDACs is a potential therapeutic strategy that could be used to reverse epigenetic modification. Trichostatin A (TSA), a powerful histone deacetylase (HDAC) inhibitor, has anti-cancer effects in numerous cancer types. However, it is not yet apparent how HDAC inhibitors affect human non-small cell lung cancer cells (NSCLC) and COPD. This study aims to investigate TSA's role in restoring mitochondrial dysfunction and its effect on hypoxia and inflammation in CD4+T cells obtained from patients with COPD and lung cancer. As a result of treatment with TSA, there is a reduction in the expression of inflammatory cytokines and a decreased enrichment of transcriptional factors associated with inflammation at VEGFA gene loci. We have seen a substantial decrease in the expression of NF-κB and HIF1α, which are the critical mediators of inflammation and hypoxia, respectively. Following TSA treatment, mtTFA expression was increased, facilitating patients with COPD and NSCLC in the recovery of their dysfunctional mitochondria. Furthermore, we have discovered that TSA treatment in patients with COPD and NSCLC may lead to immunoprotective ness by inducing Th1ness. Our finding gives a new insight into the existing body of knowledge regarding TSA-based therapeutic methods and highlights the necessity of epigenetic therapy for these devastating lung disorders.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Doença Pulmonar Obstrutiva Crônica , Humanos , NF-kappa B/metabolismo , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Epigênese Genética , Neoplasias Pulmonares/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Histona Desacetilases/uso terapêutico , Inflamação/metabolismo , Estresse Oxidativo , Hipóxia , Ácidos Hidroxâmicos/farmacologia , Ácidos Hidroxâmicos/uso terapêutico
19.
Curr Res Immunol ; 4: 100068, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37692091

RESUMO

The immune system has a variety of potential effects on a tumor microenvironment and the course of chemotherapy may vary according to that. Anticancer treatments can encourage the release of unwanted signals from senescent tumor cells or the removal of immune-suppressive cells, which can lead to immune system activation. Hence, by inducing an immunological response and conversely making cancer cells more vulnerable to immune attack, chemotherapeutic agents can destroy cancer cells. Furthermore, chemotherapy can activate anticancer immune effectors directly or indirectly by thwarting immunosuppressive pathways. Therefore, in this review, we discuss how chemotherapeutic agents take part in immunomodulation and the molecular mechanisms underlying them. We also focus on the importance of carefully addressing the conflicting effects of chemotherapy on immune responses when developing successful combination treatments based on chemotherapy and immune modulators.

20.
Curr Top Med Chem ; 23(30): 2973-2986, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37937579

RESUMO

Cancer is one of the leading causes of death, and numerous methods have been tested and used to figure out an optimum way of treatment. Besides targeted therapy, immunotherapy has proven to be effective by controlling certain immune cells. Traditional cancer therapy is met with the consequences of adverse side effects that have been a major issue for treatment; hence, a leap towards naturally occurring immunomodulators was taken to develop safer methods of treatment. One of the major immune cells responsible for the growth of tumors is regulatory T cells (Tregs). To maintain immunological homeostasis, Treg dampens abnormal immune responses to self and non-self-antigens. The transcription factor FoxP3 is responsible for their lineage specification and takes part in the production of immunosuppressive cytokines like IL10, IL35, and TGFb. This helps cancer cells to proliferate without the restriction of different immune cells like CD8+T cells, dendritic cells, monocytes/macrophages, B cells, and natural killer cells. Hence, targeting Tregs to provide unhindered immunosurveillance has proven to be a breakthrough in cancer immunotherapy. This review mainly focuses on some common naturally occurring immunomodulators derived from plant products that have earned their place as immunotherapeutic agents, along with some of their ability to suppress Tregs that can be used as an effective way to treat cancer.


Assuntos
Neoplasias , Linfócitos T Reguladores , Humanos , Linfócitos T Reguladores/patologia , Neoplasias/tratamento farmacológico , Imunoterapia , Citocinas , Fatores Imunológicos
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