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The process of efferocytosis involves removal of dying or dead cells by phagocytosis. Another term "efferosome" is used which means a fluid-filled membrane vesicle which engulfs dead cells. The process of efferocytosis works in coordination with apoptosis because before the contents of apoptotic cells are bleached out, they are engulfed by efferosomes. Thus, the microenvironment is not polluted with toxic enzymes and oxidants. A defect in the apoptotic cell clearance may participate in autoimmunity and chronic inflammation for homeostasis and proper tissue development, for which removal of dead cells is essential. This also protects from chronic inflammation and autoimmunity. In different tumor types and other diseases, efferocytosis has been studied extensively and potential pathways identified. A few of the intermediates in different pathways, which create aggressive and tolerogenic tumor microenvironment, might be considered for therapeutic or interventional purposes. Since the key players in efferocytosis are macrophages and dendritic cells, development of antigen-dependent antitumor immunity is affected by efferocytosis. The literature analysis suggests that efferocytosis is an underappreciated immune checkpoint, perhaps one that might be therapeutically targeted in the setting of cancer. The current status of efferocytosis and its role in tumor microenvironment is discussed in this article.
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Fagocitose , Microambiente Tumoral , Apoptose , Macrófagos , Transdução de SinaisRESUMO
Cisplatin and other metal-based drugs often display side effects and tumor resistance after prolonged use. Because rhenium-based anticancer complexes are often less toxic, a novel series of organorhenium complexes were synthesized of the types: XRe(CO)3Z (X = α-diimines and Z = p-toluenesulfonate, 1-naphthalenesulfonate, 2-naphthalenesulfonate, picolinate, nicotinate, aspirinate, naproxenate, flufenamate, ibuprofenate, mefenamate, tolfenamate, N-acetyl-tryptophanate), and their biological properties were examined. Specifically, in hormone-dependent MCF-7 and hormone-independent triple-negative MDA-MB-231 breast cancer cells, the p-toluenesulfonato, 1-naphthalenesulfonato, 2-naphthalenesulfonato, picolinato, nicotinato, acetylsalicylato, flufenamato, ibuprofenato, mefenamato, and N-acetyl-tryptophanato complexes were found to be far more potent than conventional drug cisplatin. DNA-binding studies were performed in each case via UV-Vis titrations, cyclic voltammetry, gel electrophoresis, and viscosity, which suggest DNA partial intercalation interaction, and the structure-activity relationship studies suggest that the anticancer activities increase with the increasing lipophilicities of the compounds, roughly consistent with their DNA-binding activities.
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Antineoplásicos , Complexos de Coordenação , Compostos Organometálicos , Rênio , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Antineoplásicos/química , Antineoplásicos/farmacologia , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Feminino , Humanos , Células MCF-7 , Compostos Organometálicos/química , Compostos Organometálicos/farmacologia , Rênio/química , Rênio/farmacologia , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologiaRESUMO
Seven organorhenium pentylcarbonate compounds (PC1-PC7) have been synthesized. DNA-binding studies of the PC-series compounds using electronic spectroscopy and gel electrophoresis suggest that the compounds presumably bind to DNA in an intercalative mode. The intrinsic binding constants for PC4, PC6, and PC7 were found to be 1.6 × 10(4), 3.9 × 10(4), and 4.2 × 10(4) M(-1), respectively. The X-ray structure determinations and density functional theory calculations indicate that the polypyridyl ligands in the compounds are nearly planar facilitating DNA binding through an intercalation mechanism. Cytotoxicity studies of 10 µM pentylcarbonate compounds against HTB-12 human astrocytoma brain cancer cells were studied for 48 h. It was observed that each of the pentylcarbonate compounds is active against the cancer cells. However, under analogous conditions, CRL-2005 rat astrocyte normal brain cells are not affected significantly.
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DNA/metabolismo , Compostos Organometálicos/química , Compostos Organometálicos/metabolismo , Rutênio/química , Animais , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cristalografia por Raios X , DNA/genética , Eletroforese em Gel de Ágar , Humanos , Substâncias Intercalantes/química , Substâncias Intercalantes/metabolismo , Substâncias Intercalantes/farmacologia , Estrutura Molecular , Compostos Organometálicos/farmacologia , Ratos , EspectrofotometriaRESUMO
Pancreatic cancer is a significant public health concern, with increasing incidence rates and limited treatment options. Recent studies have highlighted the role of the human microbiome, particularly the gut microbiota, in the development and progression of this disease. Microbial dysbiosis, characterized by alterations in the composition and function of the gut microbiota, has been implicated in pancreatic carcinogenesis through mechanisms involving chronic inflammation, immune dysregulation, and metabolic disturbances. Researchers have identified specific microbial signatures associated with pancreatic cancer, offering potential biomarkers for early detection and prognostication. By leveraging advanced sequencing and bioinformatics tools, scientists have delineated differences in the gut microbiota between pancreatic cancer patients and healthy individuals, providing insights into disease pathogenesis and potential diagnostic strategies. Moreover, the microbiome holds promise as a therapeutic target in pancreatic cancer treatment. Interventions aimed at modulating the microbiome, such as probiotics, prebiotics, and fecal microbiota transplantation, have demonstrated potential in enhancing the efficacy of existing cancer therapies, including chemotherapy and immunotherapy. These approaches can influence immune responses, alter tumor microenvironments, and sensitize tumors to treatment, offering new avenues for improving patient outcomes and overcoming therapeutic resistance. Overall, understanding the complex interplay between the microbiome and pancreatic cancer is crucial for advancing our knowledge of disease mechanisms and identifying innovative therapeutic strategies. Here we report phylogenetic analysis of the 16S microbial sequences of the pancreatic cancer mice microbiome and corresponding age matched healthy mice microbiome. We successfully identified differentially abundance of microbiota in the pancreatic cancer.
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INTRODUCTION: Men with African ancestry have the highest incidence and mortality rates of prostate cancer (PCa) worldwide. METHODS: This study aimed to identify differentially methylated genes between tumor vs. adjacent normal and aggressive vs. indolent PCa in 121 African American patients. Epigenome-wide DNA methylation patterns in tumor DNA were assessed using the human Illumina Methylation EPIC V1 array. RESULTS: Around 5,139 differentially methylated CpG-sites (q < 0.01, lΔßl > 0.2) were identified when comparing normal vs. tumor, with an overall trend of hypermethylation in prostate tumors. Multiple representative differentially methylated regions (DMRs), including immune-related genes, such as CD40, Galectin3, OX40L, and STING, were detected in prostate tumors when compared to adjacent normal tissues. Based on an epigenetic clock model, we observed that tumors' total number of stem cell divisions and the stem cell division rate were significantly higher than adjacent normal tissues. Regarding PCa aggressiveness, 2,061 differentially methylated CpG-sites (q < 0.05, lΔßl > .05) were identified when the grade group (GG)1 was compared with GG4/5. Among these 2,061 CpG sites, 155 probes were consistently significant in more than one comparison. Among these genes, several immune system genes, such as COL18A1, S100A2, ITGA4, HLA-C, and ADCYAP1, have previously been linked to tumor progression in PCa. CONCLUSION: Several differentially methylated genes involved in immune-oncologic pathways associated with disease risk or aggressiveness were identified. In addition, 261 African American-specific differentially methylated genes related to the risk of PCa were identified. These results can shedlight on potential mechanisms contributing to PCa disparities in the African American Population.
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Negro ou Afro-Americano , Metilação de DNA , Estudo de Associação Genômica Ampla , Neoplasias da Próstata , Humanos , Masculino , Negro ou Afro-Americano/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Neoplasias da Próstata/etnologia , Pessoa de Meia-Idade , Idoso , Epigenoma , Ilhas de CpG , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Biomarcadores Tumorais/genéticaRESUMO
Triple Negative Breast Cancer (TNBC) is a malignant form of cancer with very high mortality and morbidity. Epithelial to Mesenchymal Transition (EMT) is the most common pathophysiological change observed in cancer cells of epithelial origin that promotes metastasis, drug resistance and cancer stem cell formation. Since the information regarding differential gene expression in TNBC cells and cell signaling events leading to EMT is limited, this investigation was done by comparing transcriptomic data generated by RNA isolation and sequencing of a EMT model TNBC cell line in comparison to regular TNBC cells. RNA sequencing and Ingenuity Pathway Software Analysis (IPA) of the transcriptomic data revealed several upregulated and downregulated gene expressions along with novel core canonical pathways including Sirtuin signaling, Oxidative Phosphorylation and Mitochondrial dysfunction events involved in EMT changes of the TNBC cells.
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The prognosis of patients with glioblastoma multiforme, the most malignant adult glial brain tumor, remains poor in spite of advances in treatment procedures, including surgical resection, irradiation, and chemotherapy. Genetic heterogeneity of glioblastoma warrants extensive studies to gain a thorough understanding of the biology of this tumor. While there have been several studies of global transcript profiling of glioma with the identification of gene signatures for diagnosis and disease management, translation into clinics is yet to happen. In the present study, we report a novel proteomic approach by using two-dimensional difference gel electrophoresis followed by spot picking and analysis of proteins/peptides by Mass spectrometry. We report at least ten different novel proteins/peptides as identified by this technique which are differentially expressed in this cancer and could be of further importance for diagnostic, therapeutic, and prognostic approaches.
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Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/metabolismo , Glioblastoma/metabolismo , Astrócitos/metabolismo , Neoplasias Encefálicas/diagnóstico , Linhagem Celular Tumoral , Glioblastoma/diagnóstico , Humanos , Prognóstico , Proteoma/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrometria de Massas em Tandem , Eletroforese em Gel Diferencial BidimensionalRESUMO
There is a need for additional biomarkers for the diagnosis and prognosis of prostate cancer. MicroRNAs are a class of non-protein coding RNA molecules that are frequently dysregulated in different cancers including prostate cancer and show promise as diagnostic biomarkers and targets for therapy. Here we describe the role of micro RNA 146 a (miR-146a) which may serve as a diagnostic marker for prostate cancer, as indicated from the data presented in this report. Also, a pilot study indicated differential expression of miR-146a in prostate cancer cell lines and tissues from different racial groups. This report provides a novel insight into understanding the prostate carcinogenesis.
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Rhenium compounds have shown anti-cancer properties against many different types of cancer cell lines; however, the cellular signaling mechanisms involved in the cytotoxic properties of rhenium-based compounds were never deciphered or reported. In this manuscript, we report the results of an investigation done by RNA sequencing of rhenium treated A549 lung cancer cell lines along with an untreated vehicular control, analyzed by the Ingenuity Pathway Analysis (IPA) software system to decipher the core canonical pathways involved in rhenium induced cancer cell death. A549 EMT lung cancer cell lines were treated with rhenium ligand (Tricarbonylperrhenato(bathocuproine)rhenium(I), PR7) for seven days along with vehicular control. RNA was isolated from the treated and control cells and sequenced by a commercial company (PrimBio Corporation). The RNA sequencing data was analyzed by the INGNUITY software system and the core canonical pathways involved with differential gene expression were identified. Our report is showing that there are several cellular pathways involved in inducing cell death by rhenium-based compound PR7.
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Nuclear pores are large protein complexes that cross the nuclear envelope, which is the double membrane surrounding the eukaryotic cell nucleus. There are about on average 2,000 nuclear pore complexes (NPCs) in the nuclear envelope of a vertebrate cell, but it varies depending on cell type and the stage in the life cycle. The proteins that make up the NPC are known as nucleoporins. In mammalian cells, Nup107 is the homolog of yeast Nup84p nucleoporin. Nup107 contains a leucine zipper motif in its carboxyl-terminal region and numerous kinase consensus sites, but does not contain FG repeats. Previously it was reported that NUP88 and NUP107 are over expressed in many types of cancers including colon, breast, prostrate, etc. In this study, we were interested in investigating the role of NUP107 in grade 4 Astrocytoma, i.e., Glioblastoma multiforme cultured cell line. We transfected human Astrocytoma cells with Nup107-specific siRNA duplexes. The level of mRNA for Nup107 was monitored by RT-PCR, 24, 48, and 72 h after the initial transfection. Nup107 mRNA was significantly diminished by 24 h after transfection and we took that as our incubation time. Next we studied the effect of this inhibition on cell viability. We did a Trypan Blue cell viability assay and it showed increased cell death in NUP107 transfected cells than untreated control. We further tried to analyze the nature of the cell death whether apoptotic or necrotic by doing apoptosis assays like ssDNA ELISA assay, Caspase-3, and Caspase-8 assays. All the assays showed that siRNA transfected cells are undergoing increased apoptosis than control.
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Apoptose/fisiologia , Complexo de Proteínas Formadoras de Poros Nucleares/fisiologia , Sequência de Bases , Linhagem Celular Tumoral , DNA de Cadeia Simples , Ensaio de Imunoadsorção Enzimática , Humanos , Complexo de Proteínas Formadoras de Poros Nucleares/genética , RNA Interferente Pequeno , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
The novel coronavirus (SARS-COV-2) is generally referred to as Covid-19 virus has spread to 213 countries with nearly 7 million confirmed cases and nearly 400,000 deaths. Such major outbreaks demand classification and origin of the virus genomic sequence, for planning, containment, and treatment. Motivated by the above need, we report two alignment-free methods combing with CGR to perform clustering analysis and create a phylogenetic tree based on it. To each DNA sequence we associate a matrix then define distance between two DNA sequences to be the distance between their associated matrix. These methods are being used for phylogenetic analysis of coronavirus sequences. Our approach provides a powerful tool for analyzing and annotating genomes and their phylogenetic relationships. We also compare our tool to ClustalX algorithm which is one of the most popular alignment methods. Our alignment-free methods are shown to be capable of finding closest genetic relatives of coronaviruses.
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Endometrial cancer of the uterus is highly maslignant with an increase rate of morbidity and mortality in both childbearing age and postmenopausal women. Rhenium compounds have been shown to have therapeutic properties against various cancers both in vitro cell lines and in vivo animal models. In this in vitro study, we investigated the effects of a novel group of Rhenium ligands on a uterine cancer cell line. Our initial results showed that these compounds are cytotoxic, induces apoptosis and prevents tubulin polymerization in these uterine cancer cell lines, we also found these novel Rhenium compounds to be noncytocidal to healthy human blood lymphocyte cells, thus proving their safety and efficacy in future translational studies.
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Considering the prevalence of prostate cancer all over the world, it is desired to have tools, technologies, and biomarkers which help in early detection of the disease and discriminate different races and ethnic groups. Genetic information from the single gene analysis and genome-wide association studies have identified few biomarkers, however, the drivers of prostate cancer remain unknown in the majority of prostate cancer patients. In those cases where genetic association has been identified, the genes confer only a modest risk of this cancer, hence, making them less relevant for risk counseling and disease management. There is a need for additional biomarkers for diagnosis and prognosis of prostate cancer. MicroRNAs are a class of non-protein coding RNA molecules that are frequently dysregulated in different cancers including prostate cancer and show promise as diagnostic biomarkers and targets for therapy. Here we describe the role of micro RNA 146a (miR-146a) which may serve as a diagnostic and prognostic marker for prostate cancer, as indicated from the data presented in this report. Also, a pilot study indicated differential expression of miR-146a in prostate cancer cell lines and tissues from different racial groups. Reduced expression of miR-146a was observed in African American tumor tissues compared to those from European Whites This report provides a novel insight into understanding the prostate carcinogenesis.
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Cervical cancer develops through persistent infection with high-risk human papilloma virus (hrHPV) and is a leading cause of death among women worldwide and in the United States. Periodic surveillance through hrHPV and Pap smear-based testing has remarkably reduced cervical cancer incidence worldwide and in the USA. However, considerable discordance in the occurrence and outcome of cervical cancer in various populations exists. Lack of adequate health insurance appears to act as a major socioeconomic burden for obtaining cervical cancer preventive screening in a timely manner, which results in disparate cervical cancer incidence. On the other hand, cervical cancer is aggressive and often detected in advanced stages, including African American and Hispanic/Latina women. In this context, our knowledge of the underlying molecular mechanism and genetic basis behind the disparate cervical cancer outcome is limited. In this review, we shed light on our current understanding and knowledge of racially disparate outcomes in cervical cancer.
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Disparidades em Assistência à Saúde , Papillomaviridae/fisiologia , Neoplasias do Colo do Útero/virologia , Epigênese Genética , Feminino , Humanos , Modelos Biológicos , Fatores de Risco , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/terapiaRESUMO
Background: Undergoing a timely Pap smear, high-risk human papilloma virus (HPV)- and colposcopy-based testing can reduce HPV-associated cervical cancer (CC) development in women. However, in rural areas, women and minorities without insurance do not undergo periodic assessment and remain at greater risk of HPV infection and CC. Methods: In this study, 173 women from rural East Texas with various ethnic backgrounds were examined thorough HPV/Pap-based testing and colposcopic assessment. Results: Of the 113 informative cases, 77% (87/113) were positive for high-risk HPV infection and 23% of subjects (26/113) were negative. Associations between HPV positivity with young age (p = 0.002), and a low number of pregnancy (p = 0.004) and births (p = 0.005) were evident. Women with long-term use of contraceptives (OR 1.93, 95% CI, 0.80-4.69) were associated with increased risk of HPV infection. African-American women had a higher risk of abnormal Pap outcome compared to Caucasians (OR 5.31, 95% CI, 0.67-42.0). HPV seemed to be a predictor of abnormal Pap outcome (OR 1.77, 95% CI, 0.48-6.44) in these subjects. Unmarried/widowed/divorced women had an increased abnormal Pap test outcome compared to married women or women living with a partner (p = 0.01), with over 278% increased odds (OR 3.78 at 95% CI, 1.29-11.10). Insured women undergoing periodic checkups were detected early with high-risk HPV infection and abnormal Pap test/colposcopic outcome. Conclusions: Comprehensive and timely screening of uninsured women and minorities in rural East Texas are warranted, which could potentially prevent the onset of HPV-associated CC.
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Macrophages are the first line of defense in the cellular environment in response to any antigenic or foreign invasion. Since cancer cells express antigenic molecules and create a tumor microenvironment quite different from the normal cellular environment, macrophages will attack this cancer cells as foreign Invaders. However, the cancer cells adept their ability to suppress macrophage activity by secreting compounds/proteins through unknown mechanisms and train these macrophages to aid in tumorigenesis. These macrophages are commonly known as tumor associated macrophages (TAM). In this study, our goal was to find out key regulatory molecules involved in this conversion of cancer-fighting macrophages to cancer friendly macrophages. We used African American(AA) patient derived established human prostate cancer cells along with the human derived macrophages followed by Affymetrix cDNA microarray analysis. Microarray analysis of the PCa cell exposed macrophages revealed appreciable decrease in mRNA expression of several genes associated with phagocytosis process. Aberrant expression of several noncoding RNAs that control the expression of such phagocytosis associated molecules were also evident. Increased expression of oncogenic miR such as, miR-148, 615, 515, 130, 139 and markedly decreased expression of tumor suppressive miR's MiR-3130, let7c,101,103, 383 were noted. Further, TARGET SCAN analysis demonstrated these differential expression of non-coding RNA's causing down regulation of phagocytosis promoting genes elf5A, Meg3, Tubb5, Sparcl-1, Uch-1, Bsg(CD147), Ube2v, GULP, Stabilin 1 and Pamr1. There is an increase of RAP1GAP gene that causes concomitant decrease in the expression of tubulin genes that promote cytoskeletal assembly in forming phagosomes. In addition Ingenuity pathway analysis of the gene expression data also showed upregulation of antiphagocytic genes IL-10, CD 16, IL-18 and MMP-9. Some core canonical pathways showing physiology of cellular signaling obtained by data analyzed by the Ingenuity software is confirmed a very complex mechanism still to be deciphered involved in the biology of TAM formation by which the rogue cancer cells tame their enemies, the macrophages and actually make them their helper cells to survive and propagate in the tumor microenvironment and thus prepare for epithelial mesenchymal transition for future metastasis and cancer stem cell formation and progression.
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Nanotechnology refers broadly to a field of applied science and technology whose unifying theme is the control of matter on the molecular level in scales smaller than 1 micrometer, normally 1 to 100 nanometers, and the fabrication of devices within that size range. In the last five years this technology has been improved tremendously in disease diagnosis and prognosis and maximum research and clinical work has been completed in cancer. The use of various pharmaceutical nanocarriers has become one of the most important areas of nanomedicine. Novel nanotechnologies can complement and augment existing genomic and proteomic techniques to analyze variations across different tumor types, thus offering the potential to distinguish between normal and malignant cells. Sensitive biosensors constructed of nanoscale components (e.g., nanocantilevers, nanowires, and nanochannels) can recognize genetic and molecular events and have reporting capabilities, thereby offering the potential to detect rare molecular signals associated with malignancy. Such signals may then be collected for analysis by nanoscale harvesters that selectively isolate cancer-related molecules from tissues. The implication of nanotechnology in cancer is discussed in this article with an emphasis on biomarker detection, imaging studies for diagnosis, and its role in therapeutic intervention.
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Nanomedicina/métodos , Nanomedicina/tendências , Neoplasias/diagnóstico , Neoplasias/terapia , HumanosRESUMO
Prostate cancer is a serious disease in terms of its high incidence and mortality rate in the USA and around the world. The prostate specific antigen (PSA) has been used for prostate cancer diagnosis and follow-up of treatment but a number of challenges remain. Epigenetic biomarkers, especially methylation and microRNA (miR) biomarkers provide an opportunity for diagnosis, prognosis, and recurrence of prostate cancer. Differential global methylation has shown some promising results. In this chapter, the emphasis is given on those biomarkers which can be assayed noninvasively in a prospective study and in a clinic. Challenges in the field, especially the validation of potential biomarkers, and their potential solutions are provided in this chapter.
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Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Metilação , MicroRNAs/genética , Neoplasias/genética , Neoplasias/metabolismo , Grupos Populacionais/genética , Biomarcadores Tumorais , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Metilação de DNA , Perfilação da Expressão Gênica , Predisposição Genética para Doença , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Incidência , Masculino , Neoplasias/epidemiologia , Prevalência , Fatores de RiscoRESUMO
Epigenetic changes during the development of colorectal cancer (CRC) play a significant role. Along with factors such as diet, lifestyle, and genetics, oncogenic infection, bacteria alone or whole microbiome, has been associated with this tumor type. How gut microbiome contributes to CRC pathogenesis in the host is not fully understood. Most of the epigenetic studies in CRC have been conducted in populations infected with Helicobacter pylori. In the current review, we summarize how the gut microbiota contributes in colon carcinogenesis and the potential role of epigenetic mechanism in gene regulation. We discuss microbiota-mediated initiation and progression of colon tumorigenesis and have also touched upon the role of microbial metabolites as an initiator or an inhibitor for procarcinogenic or antioncogenic activities. The hypothesis of gut microbiota associated CRC revealed the dynamic and complexity of microbial interaction in initiating the development of CRC. In the multifaceted processes of colonic carcinogenesis, gradual alteration of microbiota along with their microenvironment and the potential oncopathogenic microbes mediated modulation of cancer therapy and other factors involved in microbiome dysbiosis leading to the CRC have also been discussed. This review provides a comprehensive summary of the mechanisms of CRC development, the role of microbiome or single bacterial infection in regulating the processes of carcinogenesis, and the intervention by novel therapeutics. Epigenetic mechanism involved in CRC is also discussed.
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Transformação Celular Neoplásica , Neoplasias Colorretais/etiologia , Suscetibilidade a Doenças , Epigênese Genética , Microbioma Gastrointestinal , Regulação Neoplásica da Expressão Gênica , Transformação Celular Neoplásica/genética , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/prevenção & controle , Neoplasias Colorretais/terapia , Progressão da Doença , Humanos , Imunidade , IncidênciaRESUMO
PURPOSE: Because of the scarcity of suitable brain cancer drugs, researchers are frantically trying to discover novel and highly potent drugs free of side effects and drug-resistance. Rhenium compounds are known to be nontoxic and exhibit no drug resistance. For that reason, we have developed a series of novel rhenium acetylsalicylato (RAC or ASP) complexes to test their cytotoxicity on brain cancer cells. Also we have attempted to explore the DNAbinding properties of these compounds because many drugs either directly or indirectly bind to DNA. METHODS: We have treated the RAC series compounds on human astrocytoma brain cancer cell lines and rat normal brain astrocyte cells and determined the efficacy of these complexes through in vitro cytotoxicity assay. We carried out the DNA-binding study through UV titrations of a RAC compound with DNA. Also we attempted to determine the planarity of the polypyridyl ligands of the RAC series compounds using DFT calculations. RESULTS: RAC6 is more potent than any other RAC series compounds on HTB-12 human astrocytoma cancer cells as well as on Glioblastoma Multiforme D54 cell lines. In fact, The IC-50 value of RAC6 on HTB-12 cancer cells is approximately 2 µM. As expected, the RAC series compounds were not active on normal cells. The DFT calculations on the RAC series compounds were done and suggest that the polypyridyl ligands in the complexes are planar. The UV-titrations of RAC9 with DNA were carried out. It suggests that RAC9 and possibly all RAC series compounds bind to minor grooves of the DNA. CONCLUSION: Because of the very low activity of RAC6 on normal cells and low lC50 value of on astrocytoma (HTB-12) cell lines, it is possible that RAC6 and its derivatives may potentially find application in the treatment of brain cancers. The DFT calculations and UV titrations suggest that RAC series compounds either bind to DNA intercalatively or minor grooves of the DNA or both. However, it is highly premature to make any definite statement in the absence of other techniques.