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The myelodysplastic syndrome (MDS) is a heterogeneous group of clonal disorders of hematopoietic progenitor cells related to ineffective hematopoiesis and an increased risk of transformation to acute myelogenous leukemia. MDS is divided into categories, namely lineage dysplasia (MDS-SLD), MDS with ring sideroblasts (MDS-RS), MDS with multilineage dysplasia (MDS-MLD), MDS with excess blasts (MDS-EB). The International Prognostic Classification System (IPSS) ranks the patients as very low, low, intermediate, high, and very high based on disease evolution and survival rates. Evidence points to toll-like receptor (TLR) abnormal signaling as an underlying mechanism of this disease, providing a link between MDS and immune dysfunction. Microbial signals, such as lipopolysaccharides from gram-negative bacteria, can activate or suppress TLRs. Therefore, we hypothesized that MDS patients present gut microbiota alterations associated with disease subtypes and prognosis. To test this hypothesis, we sequenced the 16S rRNA gene from fecal samples of 30 MDS patients and 16 healthy elderly controls. We observed a negative correlation between Prevotella spp. and Akkermansia spp. in MDS patients compared with the control group. High-risk patients presented a significant increase in the genus Prevotella spp. compared to the other risk categories. There was a significant reduction in the abundance of the genus Akkermansia spp. in high-risk patients compared with low- and intermediate-risk. There was a significant decrease in the genus Ruminococcus spp. in MDS-EB patients compared with controls. Our findings show a new association between gut dysbiosis and higher-risk MDS, with a predominance of gram-negative bacteria.
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Myeloid neoplasms are a group of bone marrow diseases distinguished by disruptions in the molecular pathways that regulate the balance between hematopoietic stem cell (HSC) self-renewal and the generation of specialized cells. Cytokines and chemokines, two important components of the inflammatory process, also influence hematological differentiation. In this scenario, immunological dysregulation plays a pivotal role in the pathogenesis of bone marrow neoplasms. The STING pathway recognizes DNA fragments in the cell cytoplasm and triggers an immune response by type I interferons. The role of STING in cancer has not yet been established; however, both actions, as an oncogene or tumor suppressor, have been documented in other types of cancer. Therefore, we performed a systematic review (registered in PROSPERO database #CRD42023407512) to discuss the role of STING pathway in the advancement of pathogenesis and/or prognosis for different myeloid neoplasms. In brief, scientific evidence supports investigations that primarily use cell lines from myeloid neoplasms, such as leukemia. More high-quality research and clinical trials are needed to understand the role of the STING pathway in the pathology of hematological malignancies. Finally, the STING pathway suggests being a promising therapeutic molecular target, particularly when combined with current drug therapies.
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Neoplasias Hematológicas , Proteínas de la Membrana , Humanos , Neoplasias Hematológicas/metabolismo , Neoplasias Hematológicas/patología , Neoplasias Hematológicas/inmunología , Proteínas de la Membrana/metabolismo , Trastornos Mieloproliferativos/metabolismo , Transducción de SeñalRESUMEN
To assess and validate the gene expression profile of SIRTs (SIRT1, SIRT2, SIRT3, SIRT4, SIRT5, SIRT6, and SIRT7) in relation to the pathogenesis and prognostic progression of Myelodysplastic neoplasm (MDS). Eighty bone marrow samples of patients with de novo MDS were diagnosed according to WHO 2022 and IPSS-R criteria. Ten bone marrow samples were obtained from elderly healthy volunteers and used as control samples. Gene expression levels of all SIRTs were assessed using RT-qPCR assays. Downregulation of SIRT2 (p = 0.009), SIRT3 (p = 0.048), SIRT4 (p = 0.049), SIRT5 (p = 0.046), SIRT6 (p = 0.043), and SIRT7 (p = 0.047) was identified in MDS patients compared to control individuals. Also, we identified that while SIRT2-7 genes are typically down-regulated in MDS patients compared to normal controls, there are relative expression variations among MDS patient subgroups. Specifically, SIRT4 (p = 0.029) showed increased expression in patients aged 60 or above, and both SIRT2 (p = 0.016) and SIRT3 (p = 0.036) were upregulated in patients with hemoglobin levels below 8 g/dL. SIRT2 (p = 0.045) and SIRT3 (p = 0.033) were highly expressed in patients with chromosomal abnormalities. Different SIRTs exhibited altered expression patterns concerning specific MDS clinical and prognostic characteristics. The downregulation in SIRTs genes (e.g., SIRT2 to SIRT7) expression in Brazilian MDS patients highlights their role in the disease's development. The upregulation of SIRT2 and SIRT3 in severe anemia patients suggests a potential link to manage iron overload-related complications in transfusion-dependent patients. Moreover, the association of SIRT2/SIRT3 with genomic instability and their role in MDS progression signify promising areas for future research and therapeutic targets. These findings underscore the importance of SIRT family in understanding and addressing MDS, offering novel clinical, prognostic, and therapeutic insights for patients with this condition.
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Proteínas Mitocondriales , Síndromes Mielodisplásicos , Sirtuina 3 , Sirtuinas , Humanos , Sirtuinas/genética , Sirtuinas/metabolismo , Masculino , Femenino , Anciano , Persona de Mediana Edad , Síndromes Mielodisplásicos/genética , Pronóstico , Sirtuina 3/genética , Sirtuina 3/metabolismo , Sirtuina 2/genética , Sirtuina 2/metabolismo , Adulto , Anciano de 80 o más Años , Sirtuina 1/genética , Sirtuina 1/metabolismo , Regulación Neoplásica de la Expresión Génica , Perfilación de la Expresión Génica/métodos , Estudios de Casos y ControlesRESUMEN
ABSTRACT Introduction: Immune checkpoints are regulators of the immune system response that allow self-tolerance. Molecules such as Programmed Cell Death Protein 1 (PD-1) and its Ligand (PD-L1) participate in the immune checkpoint by signaling co-inhibition of lymphocyte responses. In cancers, PD-L1 expression is associated with the immune evasion mechanism, which favors tumor growth. The use of anti-PD-1/PD-L1 drugs is already well described in solid tumors, but still not fully understood in hematologic malignancies. Myelodysplastic neoplasms (MDSs) are heterogeneous bone marrow disorders with an increased risk of progression to Acute Myeloid Leukemia (AML). The MDS affects hematopoietic stem cells and its pathogenesis is linked to genetic and epigenetic defects, in addition to immune dysregulation. The influence of the PD-L1 on the MDS remains unknown. Methods: In this study, we evaluated the mRNA expression of the PD-L1 in 53 patients with MDS, classified according to the WHO 2016 Classification. Results: Patients with dyserythropoiesis presented significantly higher PD-L1 expression than patients without dyserythropoiesis (p = 0.050). Patients classified as having MDS with an excess of blasts 2 (MDS-EB2) presented a significant upregulation in the mRNA expression of the PD-L1 compared to the MDS with an excess of blasts 1 (MDS-EB1) (p = 0.050). Furthermore, we detected three patients with very high levels of PD-L1 expression, being statistically classified as outliers. Conclusion: We suggested that the high expression of the PD-L1 is associated with a worse prognosis in the MDS and functional studies are necessary to evaluate the possible use of anti-PD-L1 therapies for high-risk MDS, such as the MDS-EBs.
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INTRODUCTION: Immune checkpoints are regulators of the immune system response that allow self-tolerance. Molecules such as Programmed Cell Death Protein 1 (PD-1) and its Ligand (PD-L1) participate in the immune checkpoint by signaling co-inhibition of lymphocyte responses. In cancers, PD-L1 expression is associated with the immune evasion mechanism, which favors tumor growth. The use of anti-PD-1/PD-L1 drugs is already well described in solid tumors, but still not fully understood in hematologic malignancies. Myelodysplastic neoplasms (MDSs) are heterogeneous bone marrow disorders with an increased risk of progression to Acute Myeloid Leukemia (AML). The MDS affects hematopoietic stem cells and its pathogenesis is linked to genetic and epigenetic defects, in addition to immune dysregulation. The influence of the PD-L1 on the MDS remains unknown. METHODS: In this study, we evaluated the mRNA expression of the PD-L1 in 53 patients with MDS, classified according to the WHO 2016 Classification. RESULTS: Patients with dyserythropoiesis presented significantly higher PD-L1 expression than patients without dyserythropoiesis (p = 0.050). Patients classified as having MDS with an excess of blasts 2 (MDS-EB2) presented a significant upregulation in the mRNA expression of the PD-L1 compared to the MDS with an excess of blasts 1 (MDS-EB1) (p = 0.050). Furthermore, we detected three patients with very high levels of PD-L1 expression, being statistically classified as outliers. CONCLUSION: We suggested that the high expression of the PD-L1 is associated with a worse prognosis in the MDS and functional studies are necessary to evaluate the possible use of anti-PD-L1 therapies for high-risk MDS, such as the MDS-EBs.
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The aim of this study was to evaluate the expression of USP7, USP15, UBE2O, and UBE2T genes in Myelodysplastic neoplasm (MDS) to identify possible targets of ubiquitination and deubiquitination in MDS pathobiology. To achieve this, eight datasets from the Gene Expression Omnibus (GEO) database were integrated, and the expression relationship of these genes was analyzed in 1092 MDS patients and healthy controls. Our results showed that UBE2O, UBE2T, and USP7 were upregulated in MDS patients compared with healthy individuals, but only in mononucleated cells collected from bone marrow samples (p < 0.001). In contrast, only the USP15 gene showed a downregulated expression compared with healthy individuals (p = 0.03). Additionally, the upregulation of UBE2T expression was identified in MDS patients with chromosomal abnormalities compared with patients with normal karyotypes (p = 0.0321), and the downregulation of UBE2T expression was associated with MDS hypoplastic patients (p = 0.033). Finally, the USP7 and USP15 genes were strongly correlated with MDS (r = 0.82; r2 = 0.67; p < 0.0001). These findings suggest that the differential expression of the USP15-USP7 axis and UBE2T may play an important role in controlling genomic instability and the chromosomal abnormalities that are a striking characteristic of MDS.
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Síndromes Mielodisplásicos , Neoplasias , Humanos , Peptidasa Específica de Ubiquitina 7/genética , Síndromes Mielodisplásicos/patología , Aberraciones Cromosómicas , Ubiquitinación , Enzimas Ubiquitina-Conjugadoras/genética , Enzimas Ubiquitina-Conjugadoras/metabolismo , Proteasas Ubiquitina-Específicas/genética , Proteasas Ubiquitina-Específicas/metabolismoRESUMEN
Differentially expressed genes (DEGs) biomarkers can be used to help diagnose and monitor the disease, as well as to determine which treatments are most effective. So, given the complexity of Myelodysplastic neoplasm (MDS), it is difficult to determine the impact and disparities of DEGs between CD34+ HSC (hematopoietic stem cells) or primary bone marrow cells (PBMC) in MDS pathogenesis, and therefore it remains largely unknown. Here, we performed an in-silico transcriptome analysis on CD34+ HSC and PBMC from 1092 MDS patients analyzing the divergences between differential gene expression patterns in these two cell types as potential pathogenic biomarkers for MDS. Initially, we observed a difference of 7117 expressed transcripts between PBMC (n = 40,165) and CD34 +HSC (n = 33,048). Also, we identified that CD34+ HSC and PBMC samples showed 240 and 2948 DEGs, respectively. In summary, we identified DEGs disparities in CD34+ HSC and PBMC cell types. However, there was a certain similarity of the activated pathways in both cellular samples based on Gene Ontology and KEGG pathways enrichment analyses. Our results provide novel insights into novel DEGs biomarkers to MDS pathogenesis with clinical significance. AVAILABILITY OF DATA AND MATERIALS: All microarray databases were obtained from Gene Expression Omnibus (https://www.ncbi.nlm.nih.gov/geo/). To evaluate the biological function of differentially expressed genes, the DAVID (Database for Annotation, Visualization and Integrated Discovery tool was used) (https://david.ncifcrf.gov/).
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Síndromes Mielodisplásicos , Neoplasias , Humanos , Transcriptoma , Leucocitos Mononucleares/metabolismo , Neoplasias/complicaciones , Antígenos CD34/metabolismo , Perfilación de la Expresión Génica , Células Madre Hematopoyéticas/metabolismo , Células de la Médula Ósea/patología , Síndromes Mielodisplásicos/patología , Biomarcadores/metabolismo , Biología Computacional/métodosRESUMEN
The state of Ceará, in the Northeast Region of Brazil, presents the simultaneous circulation of Zika (ZIKV), dengue (DENV) and chikungunya (CHIKV) viruses. In 2017 there were a high number of cases of these three arboviruses, especially CHIKV. Here, we detected the presence of arboviruses ZIKV, DENV and CHIKV and their coinfections in women in endemic regions of the city of Fortaleza, Ceará in a post-Zika epidemic year. Sociodemographic and environmental characteristics associated with arbovirus positivity were also analyzed. Women (n = 1289) between 15 and 39 years old were included. RT-qPCR was performed for virus detection and IgM antibody positivity was also analyzed. One hundred and six (8.3%) participants were positive for one or more arboviruses. Monoinfections (76; 5.9%) were distributed between 22 (1.7%) for ZIKV, 39 (3.1%) for DENV and 15 (1.2%) for CHIKV. Co-infections were detected in 30 (2.3%) of the positive participants and one case with triple infection was found. IgM positivity was found in 2.4% of ZIKV RT-qPCR, 9.6% of DENV and 16.3% of CHIKV. RT-qPCR positivity for arboviruses was associated with low socioeconomic class and presence of a water box sealing in the household. A higher positivity to the three viruses occurred in the month with the lowest wind velocity, which was also preceded by the highest peak of rain and humidity. We identified the simultaneous circulation and co-infection of ZIKV, DENV and CHIKV in Fortaleza in a post-Zika epidemic year. We also highlight the need for continuous epidemiological surveillance combined with molecular diagnostic tools.
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Arbovirus , Fiebre Chikungunya , Virus Chikungunya , Coinfección , Virus del Dengue , Dengue , Infección por el Virus Zika , Virus Zika , Humanos , Femenino , Adolescente , Adulto Joven , Adulto , Infección por el Virus Zika/epidemiología , Fiebre Chikungunya/epidemiología , Brasil/epidemiología , Dengue/epidemiología , Coinfección/epidemiologíaRESUMEN
The sirtuins (SIRT) gene family (SIRT1 to SIRT7) contains the targets implicated in cellular and organismal aging. The role of SIRTs expression in the pathogenesis and overall survival of patients diagnosed with solid tumors has been widely discussed. However, studies that seek to explain the role of these pathways in the hematopoietic aging process and the consequences of their instability in the pathogenesis of different onco-hematological diseases are still scarce. Therefore, we performed a systematic review (registered in PROSPERO database #CRD42022310079) and in silico analysis (based on GEPIA database) to discuss the role of SIRTs in the advancement of pathogenesis and/or prognosis for different hematological cancer types. In summary, given recent available scientific evidence and in silico gene expression analysis that supports the role of SIRTs in pathobiology of hematological malignances, such as leukemias, lymphomas and myeloma, it is clear the need for further high-quality research and clinical trials that expands the SIRT inhibition knowledge and its effect on controlling clonal progression caused by genomic instability characteristics of these diseases. Finally, SIRTs represent potential molecular targets in the control of the effects caused by aging on the failures of the hematopoietic system that can lead to the involvement of hematological neoplasms.
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The increase of H. pylori resistance to clarithromycin is a concern. This study evaluated the prevalence of H. pylori's primary resistance to clarithromycin and its association with virulence factors in adult dyspeptic patients and asymptomatic children. The gastric mucosa from patients (153 gastritis, 24 gastric cancer, 21 peptic ulcer) and gastric juice obtained by string test from 24 H. pylori and 23S rRNA positive asymptomatic children were included. The clarithromycin resistance was assessed by TaqMan RT-PCR 23S rRNA point mutations, A2142G and/or A2143G, and H. pylori virulence markers by PCR. Overall, the clarithromycin resistance was 14.4% (32/222), 14.2% in adults, and 12% in children, whereas origin, gender, and disease were not distinctive factors. The most prevalent point mutation was A2143G (62.5%). The point mutation was significantly less frequent in cagA-positive (11.4%) than in cagA-negative (23.6%) strains (p=0.03 OR = 0.4 95%CI = 0.19 - 0.91) as well as in cagE-positive (10.2%), cagE-negative (21.2%) (p=0.03 OR: 0.4 I.C:0.20-0.91). No difference was found in iceA or vacA alleles genotypes. Primary resistance to clarithromycin was lower than that reported in Southeast Brazil. The cagA and cagE positive H. pylori samples have few point mutations suggesting that individuals infected with virulent strains may be more susceptible to anti-H. pylori treatment.
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Infecciones por Helicobacter , Helicobacter pylori , Adulto , Antibacterianos/farmacología , Brasil , Niño , Claritromicina/farmacología , Farmacorresistencia Bacteriana/genética , Genotipo , Infecciones por Helicobacter/complicaciones , Helicobacter pylori/genética , Humanos , Pruebas de Sensibilidad Microbiana , ARN Ribosómico 23S/genética , Virulencia/genéticaRESUMEN
AIMS: DNA methylation has its distribution influenced by DNA demethylation processes with the catalytic conversion of 5-methylcytosine (5mC) into 5-hydroxymethylcytosine (5hmC). Myelodysplastic syndrome (MDS) has been associated with epigenetic dysregulation of genes related to DNA repair system, chronic immune response and cell cycle. METHODS: We evaluated the tissue DNA methylation/hydroxymethylation in bone marrow trephine biopsies of 73 patients with MDS, trying to correlate with the mRNA expression of 21 genes (POLH, POLL, REV3L, POLN, POLQ, POLI, POLK, IRF-1, IRF-2, IRF-3, IRF-4, IRF-5, IRF6, IRF-7, IRF-8,IRF-9, MAD2, CDC20, AURKA, AURKB and TPX2). RESULTS: The M-score (5mC) was significantly higher in patients with chromosomal abnormalities than patients with normal karyotype (95% CI -27.127779 to -2.368020; p=0.022). We observed a higher 5mC/5hmC ratio in patients classified as high-risk subtypes compared with low-risk subtypes (95% CI -72.922115 to -1.855662; p=0.040) as well as patients with hypercellular bone marrow compared with patients with normocellular/hypocellular bone marrow (95% CI -69.189259 to -0.511828; p=0.047) and with the presence of dyserythropoiesis (95% CI 17.077703 to 51.331388; p=0.001). DNA pols with translesion activity are significantly influenced by methylation. As 5mC immunoexpression increases, the expressions of POLH (r=-0.816; r2 =0.665; p=0.000), POLQ (r=-0.790; r2=0.624; p=0.001), PCNA (r=-0.635; r2=0.403; p=0.020), POLK (r=-0.633; r2=0.400; p=0.036 and REV1 (r=-0.578; r2=0.334; p=0.049) decrease. CONCLUSIONS: Our results confirm that there is an imbalance in the DNA methylation in MDS, influencing the development of chromosomal abnormalities which may be associated with the low expression of DNA polymerases with translesion synthesis polymerases activity.
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Aberraciones Cromosómicas , Metilación de ADN , ADN Polimerasa Dirigida por ADN/genética , Epigénesis Genética , Síndromes Mielodisplásicos/genética , 5-Metilcitosina/análogos & derivados , 5-Metilcitosina/metabolismo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biopsia , ADN Polimerasa Dirigida por ADN/metabolismo , Femenino , Humanos , Inmunohistoquímica , Cariotipificación , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/enzimología , Reacción en Cadena en Tiempo Real de la Polimerasa , Adulto JovenRESUMEN
ABSTRACT The increase of H. pylori resistance to clarithromycin is a concern. This study evaluated the prevalence of H. pylori's primary resistance to clarithromycin and its association with virulence factors in adult dyspeptic patients and asymptomatic children. The gastric mucosa from patients (153 gastritis, 24 gastric cancer, 21 peptic ulcer) and gastric juice obtained by string test from 24 H. pylori and 23S rRNA positive asymptomatic children were included. The clarithromycin resistance was assessed by TaqMan RT-PCR 23S rRNA point mutations, A2142G and/or A2143G, and H. pylori virulence markers by PCR. Overall, the clarithromycin resistance was 14.4% (32/222), 14.2% in adults, and 12% in children, whereas origin, gender, and disease were not distinctive factors. The most prevalent point mutation was A2143G (62.5%). The point mutation was significantly less frequent in cagA-positive (11.4%) than in cagA-negative (23.6%) strains (p=0.03 OR = 0.4 95%CI = 0.19 - 0.91) as well as in cagE-positive (10.2%), cagE-negative (21.2%) (p=0.03 OR: 0.4 I.C:0.20-0.91). No difference was found in iceA or vacA alleles genotypes. Primary resistance to clarithromycin was lower than that reported in Southeast Brazil. The cagA and cagE positive H. pylori samples have few point mutations suggesting that individuals infected with virulent strains may be more susceptible to anti-H. pylori treatment.
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BACKGROUND AND PURPOSE: Severe diarrhoea, a common gastrointestinal manifestation of anticancer treatment with irinotecan, might involve single nucleotide polymorphisms (SNPs) of toll-like receptors (TLRs), described as critical bacterial sensors in the gut. Here, colorectal cancer patients carrying missense TLR4 A896G (rs4986790) or C1,196T (rs4986791) SNPs and Tlr4 knockout (Tlr4-/-) mice were given irinotecan to investigate the severity of the induced diarrhoea. EXPERIMENTAL APPROACH: Forty-six patients treated with irinotecan-based regimens had diarrhoea severity analysed according to TLR4 genotypes. In the experimental setting, wild-type (WT) or Tlr4-/- mice were given irinotecan (45 or 75 mg·kg-1 , i.p.) or saline (3 ml·kg-1 ). Diarrhoea severity was evaluated by measuring intestinal injury and inflammatory markers expression after animals were killed. KEY RESULTS: All patients with TLR4 SNPs chemotherapy-treated presented diarrhoea, whereas gastrointestinal toxicity was observed in 50% of the wild homozygous individuals. Mice injected with irinotecan presented systemic bacterial translocation and increased TLR4 immunostaining in the intestine. In line with the clinical findings, Tlr4 gene deficiency enhanced irinotecan-related diarrhoea and TLR9 expression in mice. An increased myeloperoxidase activity and Il-18 expression along with IL-10 decreased production in Tlr4-/- mice also indicated an intensified intestinal damage and inflammatory response. CONCLUSION AND IMPLICATIONS: TLR4 deficiency upregulates TLR9 expression and enhances intestinal damage and the severity of late-onset diarrhoea during irinotecan-based treatment. Identifying patients genetically predisposed to chemotherapy-associated diarrhoea is a strategy toward precision medicine.
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Diarrea , Irinotecán , Mucositis , Receptor Toll-Like 4 , Receptor Toll-Like 9 , Animales , Diarrea/inducido químicamente , Diarrea/genética , Humanos , Irinotecán/toxicidad , Ratones , Mucositis/inducido químicamente , Mucositis/genética , Receptor Toll-Like 4/genética , Receptor Toll-Like 9/genéticaRESUMEN
Toll-like receptors are mutated or overexpressed in up to 50% of patients with myelodysplastic syndrome (MDS). Endogenous retroviruses (ERV) trigger TLR3 leading to interferon regulatory genes (IRFs) activation. We evaluated if the ERVs-TLR3-IRF axis activation would be linked to MDS pathogenesis and we also conducted a detailed cancer analysis of the ERVs, TLR3 and IRFs gene expression in 30 cancer types using GEPIA database. Seventy-nine bone marrow samples from patients with MDS were evaluated for cytogenetics and quantitative realtime PCR of TLR3, ERVK6, ERVW-1, ERV3-1, IRF3 and IRF7. Patients with dyserythropoiesis showed higher TLR3 (p = 0.035), ERVK6 (p = 0.001), ERVW1 (p = 0.045) and ERV3-1 (p = 0.016) expression than patients without dyserythropoiesis. Upregulation of Interferon Regulatory Factors, IRF3 and IRF7, was associated with poor prognostic markers in MDS such as > 10% of blasts (p = 0.003-IRF3; p = 0.009-IRF7), low platelets count (< 50.000/mm3) (p = 0.001-IRF3; p = 0.021-IRF7), transfusion dependence (p = 0.014-IRF3) and chromosomal abnormalities (p = 0.036-IRF7). We found strong correlations between ERVK6-ERVW1 (r = 0.800; r2 = 0.640; p = 0.000), ERVW1-ERV3-1 (r = 0.715; r2 = 0.511; p = 0.000), and IRF7-IRF3 (r = 0.567; r2 = 0.321; p = 0.000) and moderate correlation between ERVK6-ERV3-1(r = 0.485; r2 = 0.235; p = 0.000), ERVW1-IRF7 (r = 0.389; r2 = 0.151; p = 0.001), ERVW1-IRF3 (r = 0.357; r2 = 0.127; p = 0.004), ERV3-1-IRF7 (r = 0.314; r2 = 0.098; p = 0.009), and ERV3-1-IRF3 (r = 0.324; r2 = 0.104; p = 0.007). Using GEPIA Database in 30 cancer types, we detected a typical pattern of upregulation as here presented in MDS. We suggest TLR3 activation by ERVs is linked to MDS pathogenesis leading to bone marrow failure. Abnormal double-stranded RNA (dsRNA) expression of Endogenous Retroviruses (ERV) triggers TLR3 hyperactivation. This induces IRF3, IRF7, and NF-kB to translocate to the nucleus and activate transcription of IFNα/ß which binds to the type I-IFN receptor promoting interferon response. Thus, just as TLR4 induces a crucial myeloid shift, the ERVs-TLR3 axis may play an important role in establishing one of the most striking characteristics in MDS, dyserythropoiesis.
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Biomarcadores de Tumor/genética , Retrovirus Endógenos/genética , Regulación Neoplásica de la Expresión Génica , Factor 3 Regulador del Interferón/metabolismo , Factor 7 Regulador del Interferón/metabolismo , Síndromes Mielodisplásicos/etiología , Receptor Toll-Like 3/genética , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/metabolismo , Retrovirus Endógenos/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/metabolismo , Síndromes Mielodisplásicos/patología , Pronóstico , Receptor Toll-Like 3/metabolismo , Adulto JovenRESUMEN
Exposure to pesticides is considered a major factor underlying increased risk of hematological disorders in agricultural workers due to its carcinogenic potential. However, genotoxic impact of pesticides in DNA integrity of bone marrow stem cells (BMSC) of farmers exposed is not yet well known. We evaluated presence of chromosomal abnormalities (CA) and mRNA expression of DNA repair targets (ATM, BRCA1, BRCA2, RAD51, XRCC5, XRCC6, LIG4, CSA, CSB, XPA, XPC, XPG) in 90 bone marrow samples of farmers divided into three groups: commercial farming (CF), family farming (FF) and organic farming (OF). Our results showed that farmers in CF (72.7 %) and FF (27.3 %) groups had significantly higher values of CA when compared to OF group (0.0 %; p = 0.003). CF showed lower XPG (p = 0.008), CSA (p < 0.001), ATM (p = 0.036) and LIG4 (p = 0.004) mRNA expression than OF. FF presented lower XPG (p = 0.012) and LIG4 (p = 0.004) expression than OF. CF + FF individual with ≥12 years of exposure to pesticides showed decreased mRNA expression of XPC (p = 0.001), XPG (p = 0.010), CSB (p = 0.05), ATM (p = 0.030) and LIG4 (p = 0.044) than those who have been exposed for <12 years. CF + FF with CA showed a lower expression of BRCA2 when compared to CF + FF group without CA (p = 0.007). These results highlight that genotoxic exposure to pesticides negatively affects expression profile of important DNA repair genes in BMSC, favoring irreparable chromosomal lesions.
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Aberraciones Cromosómicas/inducido químicamente , Reparación del ADN/genética , Regulación de la Expresión Génica/efectos de los fármacos , Mutágenos/toxicidad , Exposición Profesional/efectos adversos , Plaguicidas/toxicidad , Adulto , Anciano , Agricultura , Médula Ósea/metabolismo , Brasil , Daño del ADN , Agricultores , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
Cancer-specific defects in DNA repair pathways create the opportunity to employ synthetic lethality approach. Recently, GEMA (gene expression and mutation analysis) approach detected insufficient expression of BRCA or NHEJ (non-homologous end joining) to predict PARP inhibitors response. We evaluated a possible role of DNA repair pathways using gene expression of single-strand break (XPA, XPC, XPG/ERCC5, CSA/ERCC8, and CSB/ERCC6) and double-strand break (ATM, BRCA1, BRCA2, RAD51, XRCC5, XRCC6, LIG4) in 92 patients with myelodysplastic syndrome (73 de novo, 9 therapy-related (t-MDS). Therapy-related MDS (t-MDS) demonstrated a significant downregulation of axis BRCA1-BRCA2-RAD51 comparing to normal controls (p = 0.048, p = 0.001, p = 0.001). XRCC6 showed significantly low expression in de novo MDS comparing to controls (p = 0.039) and for patients who presented chromosomal abnormalities (p = 0.047). Downregulation of LIG4 was consistently associated with poor prognostic markers in de novo MDS (hemoglobin < 8 g/dL (p = 0.040), neutrophils < 800/mm3 (p < 0.001), patients with excess of blasts (p = 0.001), very high (p = 0.002)/high IPSS-R (p = 0.043) and AML transformation (p < 0.001). We also performed an evaluation of GEPIA Database in 30 cancer types and detected a typical pattern of downregulation as here presented in primary or secondary MDS. All these results suggest synthetic lethality approach can be tested with DNA repair genes (beyond that of BRCA1/2 status) for de novo and therapy-related myelodysplastic syndrome and may encourage clinical trials evaluating the use of PARP1 inhibitors in MDS.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , ADN Ligasa (ATP)/genética , Enzimas Reparadoras del ADN/genética , Autoantígeno Ku/genética , Síndromes Mielodisplásicos/genética , Mutaciones Letales Sintéticas , Anciano , Anciano de 80 o más Años , Regulación hacia Abajo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/tratamiento farmacológico , Síndromes Mielodisplásicos/patología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/uso terapéuticoRESUMEN
Myelodysplastic syndrome (MDS) are a heterogeneous group of clonal disease characterized by insufficiency of bone marrow, increase of apoptosis and increased risk of acute leukemia progression. Proteins related to the mitotic spindle (AURKA, AURKB, TPX2), to the mitotic checkpoint (MAD2, CDC20) and the regulation of the cell cycle (p21) are directly related to chromosomal stability and tumor development. This study aimed to evaluate the mRNA expression levels of these genes in 101 MDS patients using a real-time PCR methodology. We identified that CDC20 expression are increased in patients with dysmegakaryopoiesis (p=0.024), thrombocytopenia (p=0.000) and high-risk patients (p=0.014, 0.018) MAD2 expression are decreased in patients with 2 or 3 cytopenias (p=0.000) and neutrophil below 800/mm3. TPX2 is also overexpressed in patients presenting dysmegakaryopoiesis (p=0.009). A decrease in AURKA and AURKB expression were observed in patients with altered karyotype (p=0.000), who presented dysplasia in 3 lineages (p=0.000; 0.017) and hemoglobin inferior to 8g/dL (p=0.024). The expression of AURKA, AURKB and MAD2 (p=0.000; 0.001; 0.025) were decreased in patients with hypoplastic MDS, associated with high frequency of chromosomal alterations and high mortality rate. This study reaffirms the importance of aurora kinases and mitotic spindle genes to the pathogenesis and clinical evolution of MDS.