RESUMO
Burkitt lymphoma (BL) is responsible for many childhood cancers in sub-Saharan Africa, where it is linked to recurrent or chronic infection by Epstein-Barr virus or Plasmodium falciparum. However, whether human leukocyte antigen (HLA) polymorphisms, which regulate immune response, are associated with BL has not been well investigated, which limits our understanding of BL etiology. Here we investigate this association among 4,645 children aged 0-15 years, 800 with BL, enrolled in Uganda, Tanzania, Kenya, and Malawi. HLA alleles are imputed with accuracy >90% for HLA class I and 85-89% for class II alleles. BL risk is elevated with HLA-DQA1*04:01 (adjusted odds ratio [OR] = 1.61, 95% confidence interval [CI] = 1.32-1.97, P = 3.71 × 10-6), with rs2040406(G) in HLA-DQA1 region (OR = 1.43, 95% CI = 1.26-1.63, P = 4.62 × 10-8), and with amino acid Gln at position 53 versus other variants in HLA-DQA1 (OR = 1.36, P = 2.06 × 10-6). The associations with HLA-DQA1*04:01 (OR = 1.29, P = 0.03) and rs2040406(G) (OR = 1.68, P = 0.019) persist in mutually adjusted models. The higher risk rs2040406(G) variant for BL is associated with decreased HLA-DQB1 expression in eQTLs in EBV transformed lymphocytes. Our results support the role of HLA variation in the etiology of BL and suggest that a promising area of research might be understanding the link between HLA variation and EBV control.
Assuntos
Linfoma de Burkitt , Infecções por Vírus Epstein-Barr , Criança , Humanos , Linfoma de Burkitt/genética , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/genética , Herpesvirus Humano 4/genética , Cadeias alfa de HLA-DQ/genéticaRESUMO
Burkitt lymphoma (BL) is an aggressive B-cell lymphoma that significantly contributes to childhood cancer burden in sub-Saharan Africa. Plasmodium falciparum, which causes malaria, is geographically associated with BL, but the evidence remains insufficient for causal inference. Inference could be strengthened by demonstrating that mendelian genes known to protect against malaria-such as the sickle cell trait variant, HBB-rs334(T)-also protect against BL. We investigated this hypothesis among 800 BL cases and 3845 controls in four East African countries using genome-scan data to detect polymorphisms in 22 genes known to affect malaria risk. We fit generalized linear mixed models to estimate odds ratios (OR) and 95% confidence intervals (95% CI), controlling for age, sex, country, and ancestry. The ORs of the loci with BL and P. falciparum infection among controls were correlated (Spearman's ρ = 0.37, p = .039). HBB-rs334(T) was associated with lower P. falciparum infection risk among controls (OR = 0.752, 95% CI 0.628-0.9; p = .00189) and BL risk (OR = 0.687, 95% CI 0.533-0.885; p = .0037). ABO-rs8176703(T) was associated with decreased risk of BL (OR = 0.591, 95% CI 0.379-0.992; p = .00271), but not of P. falciparum infection. Our results increase support for the etiological correlation between P. falciparum and BL risk.
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Linfoma de Burkitt , Malária Falciparum , Malária , Traço Falciforme , Humanos , África Oriental , Alelos , Linfoma de Burkitt/epidemiologia , Linfoma de Burkitt/genética , Malária Falciparum/epidemiologia , Malária Falciparum/genética , Malária Falciparum/complicações , Traço Falciforme/epidemiologia , Traço Falciforme/genética , Traço Falciforme/complicações , Nectinas/metabolismoRESUMO
In high-income countries, mosaic chromosomal alterations in peripheral blood leukocytes are associated with an elevated risk of adverse health outcomes, including hematologic malignancies. We investigate mosaic chromosomal alterations in sub-Saharan Africa among 931 children with Burkitt lymphoma, an aggressive lymphoma commonly characterized by immunoglobulin-MYC chromosomal rearrangements, 3822 Burkitt lymphoma-free children, and 674 cancer-free men from Ghana. We find autosomal and X chromosome mosaic chromosomal alterations in 3.4% and 1.7% of Burkitt lymphoma-free children, and 8.4% and 3.7% of children with Burkitt lymphoma (P-values = 5.7×10-11 and 3.74×10-2, respectively). Autosomal mosaic chromosomal alterations are detected in 14.0% of Ghanaian men and increase with age. Mosaic chromosomal alterations in Burkitt lymphoma cases include gains on chromosomes 1q and 8, the latter spanning MYC, while mosaic chromosomal alterations in Burkitt lymphoma-free children include copy-neutral loss of heterozygosity on chromosomes 10, 14, and 16. Our results highlight mosaic chromosomal alterations in sub-Saharan African populations as a promising area of research.
Assuntos
Linfoma de Burkitt , Masculino , Criança , Humanos , Linfoma de Burkitt/genética , Linfoma de Burkitt/patologia , Gana , Aberrações Cromossômicas , Leucócitos/patologia , Imunoglobulinas/genética , Translocação GenéticaRESUMO
FGFR3 and PIK3CA are among the most frequently mutated genes in bladder tumors. We hypothesized that recurrent mutations in these genes might be caused by common carcinogenic exposures such as smoking and other factors. We analyzed 2,816 bladder tumors with available data on FGFR3 and/or PIK3CA mutations, focusing on the most recurrent mutations detected in ≥10% of tumors. Compared to tumors with other FGFR3/PIK3CA mutations, FGFR3-Y375C was more common in tumors from smokers than never-smokers (P = 0.009), while several APOBEC-type driver mutations were enriched in never-smokers: FGFR3-S249C (P = 0.013) and PIK3CA-E542K/PIK3CA-E545K (P = 0.009). To explore possible causes of these APOBEC-type mutations, we analyzed RNA sequencing (RNA-seq) data from 798 bladder tumors and detected several viruses, with BK polyomavirus (BKPyV) being the most common. We then performed IHC staining for polyomavirus (PyV) Large T-antigen (LTAg) in an independent set of 211 bladder tumors. Overall, by RNA-seq or IHC-LTAg, we detected PyV in 26 out of 1,010 bladder tumors with significantly higher detection (P = 4.4 × 10-5), 25 of 554 (4.5%) in non-muscle-invasive bladder cancers (NMIBC) versus 1 of 456 (0.2%) of muscle-invasive bladder cancers (MIBC). In the NMIBC subset, the FGFR3/PIK3CA APOBEC-type driver mutations were detected in 94.7% (18/19) of PyV-positive versus 68.3% (259/379) of PyV-negative tumors (P = 0.011). BKPyV tumor positivity in the NMIBC subset with FGFR3- or PIK3CA-mutated tumors was also associated with a higher risk of progression to MIBC (P = 0.019). In conclusion, our results support smoking and BKPyV infection as risk factors contributing to bladder tumorigenesis in the general patient population through distinct molecular mechanisms. PREVENTION RELEVANCE: Tobacco smoking likely causes one of the most common mutations in bladder tumors (FGFR3-Y375C), while viral infections might contribute to three others (FGFR3-S249C, PIK3CA-E542K, and PIK3CA-E545K). Understanding the causes of these mutations may lead to new prevention and treatment strategies, such as viral screening and vaccination.
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Neoplasias da Bexiga Urinária , Viroses , Humanos , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia , Mutação , Bexiga Urinária/patologia , Classe I de Fosfatidilinositol 3-Quinases/genéticaRESUMO
Interferon lambda 4 (IFN-λ4) is a novel type-III interferon that can be expressed only by carriers of the genetic variant rs368234815-dG within the first exon of the IFNL4 gene. Genetic inability to produce IFN-λ4 (in carriers of the rs368234815-TT/TT genotype) has been associated with improved clearance of hepatitis C virus (HCV) infection. The IFN-λ4-expressing rs368234815-dG allele (IFNL4-dG) is most common (up to 78%) in West sub-Saharan Africa (SSA), compared to 35% of Europeans and 5% of individuals from East Asia. The negative selection of IFNL4-dG outside Africa suggests that its retention in African populations could provide survival benefits, most likely in children. To explore this hypothesis, we conducted a comprehensive association analysis between IFNL4 genotypes and the risk of childhood Burkitt lymphoma (BL), a lethal infection-associated cancer most common in SSA. We used genetic, epidemiologic, and clinical data for 4,038 children from the Epidemiology of Burkitt Lymphoma in East African Children and Minors (EMBLEM) and the Malawi Infections and Childhood Cancer case-control studies. Generalized linear mixed models fit with the logit link controlling for age, sex, country, P. falciparum infection status, population stratification, and relatedness found no significant association between BL risk and 3 coding genetic variants within IFNL4 (rs368234815, rs117648444, and rs142981501) and their combinations. Because BL occurs in children 6-9 years of age who survived early childhood infections, our results suggest that additional studies should explore the associations of IFNL4-dG allele in younger children. This comprehensive study represents an important baseline in defining the health effects of IFN-λ4 in African populations.
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Linfoma de Burkitt , Hepatite C , Pré-Escolar , Criança , Humanos , Linfoma de Burkitt/genética , Genótipo , Hepatite C/complicações , Hepatite C/genética , Hepacivirus/genética , África Oriental , Interleucinas/genética , Interleucinas/farmacologia , Polimorfismo de Nucleotídeo ÚnicoRESUMO
A small percentage of bladder cancers in the general population have been found to harbor DNA viruses. In contrast, up to 25% of tumors of solid organ transplant recipients, who are at an increased risk of developing bladder cancer and have an overall poorer outcomes, harbor BK polyomavirus (BKPyV). To better understand the biology of the tumors and the mechanisms of carcinogenesis from potential oncoviruses, we performed whole genome and transcriptome sequencing on bladder cancer specimens from 43 transplant patients. Nearly half of the tumors from this patient population contained viral sequences. The most common were from BKPyV (N=9, 21%), JC polyomavirus (N=7, 16%), carcinogenic human papillomaviruses (N=3, 7%), and torque teno viruses (N=5, 12%). Immunohistochemistry revealed variable Large T antigen expression in BKPyV-positive tumors ranging from 100% positive staining of tumor tissue to less than 1%. In most cases of BKPyV-positive tumors, the viral genome appeared to be clonally integrated into the host chromosome consistent with microhomology-mediated end joining and coincided with focal amplifications of the tumor genome similar to other virus-mediated cancers. Significant changes in host gene expression consistent with the functions of BKPyV Large T antigen were also observed in these tumors. Lastly, we identified four mutation signatures in our cases, with those attributable to APOBEC3 and SBS5 being the most abundant. Mutation signatures associated with an antiviral drug, ganciclovir, and aristolochic acid, a nephrotoxic compound found in some herbal medicines, were also observed. The results suggest multiple pathways to carcinogenesis in solid organ transplant recipients with a large fraction being virus-associated.
Assuntos
Vírus BK , Transplante de Órgãos , Infecções por Polyomavirus , Neoplasias da Bexiga Urinária , Humanos , Infecções por Polyomavirus/complicações , Infecções por Polyomavirus/epidemiologia , Vírus BK/genética , Carcinogênese , Neoplasias da Bexiga Urinária/genética , Antígenos Virais de Tumores , Transplante de Órgãos/efeitos adversosRESUMO
BACKGROUND: Diesel exhaust is a complex mixture, including polycyclic aromatic hydrocarbons (PAH) and nitrated PAHs (nitro-PAH), many of which are potent mutagens and possible bladder carcinogens. To explore the association between diesel exposure and bladder carcinogenesis, we examined the relationship between exposure and somatic mutations and mutational signatures in bladder tumors. METHODS: Targeted sequencing was conducted in bladder tumors from the New England Bladder Cancer Study. Using data on 797 cases and 1,418 controls, two-stage polytomous logistic regression was used to evaluate etiologic heterogeneity between bladder cancer subtypes and quantitative, lifetime estimates of respirable elemental carbon (REC), a surrogate for diesel exposure. Poisson regression was used to evaluate associations between REC and mutational signatures. RESULTS: We observed significant heterogeneity in the diesel-bladder cancer risk relationship, with a strong positive association among cases with high-grade, nonmuscle invasive TP53-mutated tumors compared with controls [ORTop Tertile vs.Unexposed, 4.8; 95% confidence interval (CI), 2.2-10.5; Ptrend < 0.001; Pheterogeneity = 0.002]. In muscle-invasive tumors, we observed a positive association between diesel exposure and the nitro-PAH signatures of 1,6-dintropyrene (RR, 1.93; 95% CI, 1.28-2.92) and 3-nitrobenzoic acid (RR, 1.97; 95% CI, 1.33-2.92). CONCLUSIONS: The relationship between diesel exhaust and bladder cancer was heterogeneous based on the presence of TP53 mutations in tumors, further supporting the link between PAH exposure and TP53 mutations in carcinogenesis. Future studies that can identify nitro-PAH signatures in exposed tumors are warranted to add human data supporting the link between diesel and bladder cancer. IMPACT: This study provides additional insight into the etiology and possible mechanisms related to diesel exhaust-induced bladder cancer.
Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Neoplasias da Bexiga Urinária , Humanos , Emissões de Veículos/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Nitratos , Neoplasias da Bexiga Urinária/induzido quimicamente , Neoplasias da Bexiga Urinária/epidemiologia , Neoplasias da Bexiga Urinária/genética , Mutação , CarcinogêneseRESUMO
BACKGROUND: IFNL4 genetic variants that are strongly associated with clearance of hepatitis C virus have been linked to risk of certain opportunistic infections (OIs) and cancers, including Kaposi sarcoma, cytomegalovirus infection, and herpes simplex virus infection. As the interferon (IFN) λ family plays a role in response to viral, bacterial, and fungal infections, IFNL4 genotype might affect risk for a wide range of OIs/cancers. METHODS: We examined associations between genotype for the functional IFNL4 rs368234815 polymorphism and incidence of 16 OIs/cancers among 2310 men with human immunodeficiency virus (2038 white; 272 black) enrolled in the Multicenter AIDS Cohort Study during 1984-1990. Our primary analyses used Cox proportional hazards models adjusted for self-reported racial ancestry to estimate hazard ratios with 95% confidence intervals, comparing participants with the genotypes that generate IFN-λ4 and those with the genotype that abrogates IFN-λ4. We censored follow-up at the introduction of highly effective antiretroviral therapies. RESULTS: We found no statistically significant association between IFNL4 genotype and the incidence of Kaposi sarcoma (hazard ratio, 0.92 [95% confidence interval, .76-1.11]), cytomegalovirus infection (0.94 [.71-1.24]), herpes simplex virus infection (1.37 [.68-2.93]), or any other OI/cancer. We observed consistent results using additive genetic models and after controlling for CD4 cell count through time-dependent adjustment or restriction to participants with a low CD4 cell count. CONCLUSIONS: The absence of associations between IFNL4 genotype and these OIs/cancers provides evidence that this gene does not affect the risk of disease from opportunistic pathogens.
Assuntos
Infecções por Citomegalovirus , Infecções por HIV , HIV-1 , Herpes Simples , Infecções Oportunistas , Sarcoma de Kaposi , Masculino , Humanos , Estudos de Coortes , Genótipo , Infecções por HIV/complicações , Infecções por HIV/genética , Herpes Simples/complicações , Herpes Simples/epidemiologia , Herpes Simples/genética , Infecções por Citomegalovirus/complicações , Infecções por Citomegalovirus/epidemiologia , Infecções por Citomegalovirus/genética , Interleucinas/genética , Polimorfismo de Nucleotídeo ÚnicoRESUMO
BACKGROUND: By-products are formed when disinfectants react with organic matter in source water. The most common class of disinfection by-products, trihalomethanes (THMs), have been linked to bladder cancer. Several studies have shown exposure-response associations with THMs in drinking water and bladder cancer risk. Few epidemiologic studies have evaluated gene-environment interactions for total THMs (TTHMs) with known bladder cancer susceptibility variants. OBJECTIVES: In this study, we investigated the combined effect on bladder cancer risk contributed by TTHMs, bladder cancer susceptibility variants identified through genome-wide association studies, and variants in several candidate genes. METHODS: We analyzed data from two large case-control studies-the New England Bladder Cancer Study (n/n=989 cases/1,162 controls), a population-based study, and the Spanish Bladder Cancer Study (n/n=706 cases/772 controls), a hospital-based study. Because of differences in exposure distributions and metrics, we estimated effects of THMs and genetic variants within each study separately using adjusted logistic regression models to calculate odds ratios (ORs) and 95% confidence intervals (CI) with and without interaction terms, and then combined the results using meta-analysis. RESULTS: Of the 16 loci showing strong evidence of association with bladder cancer, rs907611 at 11p15.5 [leukocyte-specific protein 1 (LSP1 region)] showed the strongest associations in the highest exposure category in each study, with evidence of interaction in both studies and in meta-analysis. In the highest exposure category, we observed OR=1.66 (95% CI: 1.17, 2.34, p-trend=0.005) for those with the rs907611-GG genotype and p-interaction=0.02. No other genetic variants tested showed consistent evidence of interaction. DISCUSSION: We found novel suggestive evidence for a multiplicative interaction between a putative bladder carcinogen, TTHMs, and genotypes of rs907611. Given the ubiquitous exposure to THMs, further work is needed to replicate and extend this finding and to understand potential molecular mechanisms. https://doi.org/10.1289/EHP9895.
Assuntos
Desinfetantes , Água Potável , Neoplasias da Bexiga Urinária , Poluentes Químicos da Água , Estudos de Casos e Controles , Desinfetantes/análise , Desinfecção , Feminino , Estudo de Associação Genômica Ampla , Humanos , Modelos Logísticos , Masculino , Polimorfismo Genético , Trialometanos/análise , Trialometanos/toxicidade , Neoplasias da Bexiga Urinária/induzido quimicamente , Neoplasias da Bexiga Urinária/epidemiologia , Neoplasias da Bexiga Urinária/genética , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidadeRESUMO
Recent genomic studies suggest that Asian breast cancer (BC) may have distinct somatic features; however, most comparisons of BC genomic features across populations did not account for differences in age, subtype, and sequencing methods. In this study, we analyzed whole-exome sequencing (WES) data to characterize somatic copy number alterations (SCNAs) and mutation profiles in 98 Hong Kong BC (HKBC) patients and compared with those from The Cancer Genome Atlas of European ancestry (TCGA-EA, N = 686), which had similar distributions of age at diagnosis and PAM50 subtypes as in HKBC. We developed a two-sample Poisson model to compare driver gene selection pressure, which reflects the effect sizes of cancer driver genes, while accounting for differences in sample size, sequencing platforms, depths, and mutation calling methods. We found that somatic mutation and SCNA profiles were overall very similar between HKBC and TCGA-EA. The selection pressure for small insertions and deletions (indels) in GATA3 (false discovery rate (FDR) corrected p < 0.01) and single-nucleotide variants (SNVs) in TP53 (nominal p = 0.02, FDR corrected p = 0.28) was lower in HKBC than in TCGA-EA. Among the 13 signatures of single-base substitutions (SBS) that are common in BC, we found a suggestively higher contribution of SBS18 and a lower contribution of SBS1 in HKBC than in TCGA-EA, while the two APOBEC-induced signatures showed similar prevalence. Our results suggest that the genomic landscape of BC was largely very similar between HKBC and TCGA-EA, despite suggestive differences in some driver genes and mutational signatures that warrant future investigations in large and diverse Asian populations.
RESUMO
IFNL3/IFNL4 polymorphisms are inversely associated with the risk of chronic hepatitis C virus (HCV) infection and cirrhosis, two major risk factors for developing hepatocellular carcinoma (HCC). To further explore these inverse associations and their molecular underpinnings, we analyzed IFNL3/IFNL4 polymorphisms represented by the IFNL4 genotype (presence of rs368234815-dG or rs12979860-T alleles) in HCV patients: 2969 from Japan and 2931 from Taiwan. IFNL4 genotype was associated with an increased risk of HCV-related HCC (OR=1.28, 95%CI=1.07-1.52, P=0.0058) in the general population of Japanese patients, but not in Taiwanese patients who achieved treatment-induced viral clearance. IFNL4 genotype was also associated with a decreased risk of cirrhosis (OR=0.66, 95%CI=0.46-0.93, P=0.018, in Taiwanese patients). We then engineered HepG2 cells to inducibly express IFN-λ4 in the presence or absence of interferon lambda receptor 1 (IFNLR1). Induction of IFN-λ4 resulted in its intracellular accumulation, mainly in lysosomes and late endosomes, and increased ER stress, leading to apoptosis and reduced proliferation. We identified the very-low-density lipoprotein receptor (VLDLR), which facilitates HCV entry into hepatocytes, as a transcript induced by IFN-λ4 but not IFN-λ3. Our results suggest that the molecular mechanisms underlying the anti-cirrhotic but pro-HCV associations observed for IFNL3/IFNL4 polymorphisms are, at least in part, contributed by intracellular accumulation of IFN-λ4 causing ER stress in hepatic cells.
Assuntos
Carcinoma Hepatocelular/metabolismo , Estresse do Retículo Endoplasmático , Hepatite C/metabolismo , Interleucinas/metabolismo , Cirrose Hepática/metabolismo , Neoplasias Hepáticas/metabolismo , Fígado/metabolismo , Adulto , Apoptose , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/virologia , Estudos de Casos e Controles , Proliferação de Células , Bases de Dados Factuais , Feminino , Predisposição Genética para Doença , Células Hep G2 , Hepatite C/genética , Hepatite C/virologia , Humanos , Interferons/genética , Interleucinas/genética , Japão , Fígado/patologia , Cirrose Hepática/genética , Cirrose Hepática/prevenção & controle , Cirrose Hepática/virologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Fenótipo , Polimorfismo Genético , Fatores de Proteção , Medição de Risco , Fatores de Risco , TaiwanRESUMO
PURPOSE: Exome- and whole-genome sequencing of muscle-invasive bladder cancer has revealed important insights into the molecular landscape; however, there are few studies of non-muscle-invasive bladder cancer with detailed risk factor information. EXPERIMENTAL DESIGN: We examined the relationship between smoking and other bladder cancer risk factors and somatic mutations and mutational signatures in bladder tumors. Targeted sequencing of frequently mutated genes in bladder cancer was conducted in 322 formalin-fixed paraffin-embedded bladder tumors from a population-based case-control study. Logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (CI), evaluating mutations and risk factors. We used SignatureEstimation to extract four known single base substitution mutational signatures and Poisson regression to calculate risk ratios (RR) and 95% CIs, evaluating signatures and risk factors. RESULTS: Non-silent KDM6A mutations were more common in females than males (OR = 1.83; 95% CI, 1.05-3.19). There was striking heterogeneity in the relationship between smoking status and established single base substitution signatures: current smoking status was associated with greater ERCC2-Signature mutations compared with former (P = 0.024) and never smoking (RR = 1.40; 95% CI, 1.09-1.80; P = 0.008), former smoking was associated with greater APOBEC-Signature13 mutations (P = 0.05), and never smoking was associated with greater APOBEC-Signature2 mutations (RR = 1.54; 95% CI, 1.17-2.01; P = 0.002). There was evidence that smoking duration (the component most strongly associated with bladder cancer risk) was associated with ERCC2-Signature mutations and APOBEC-Signature13 mutations among current (P trend = 0.005) and former smokers (P = 0.0004), respectively. CONCLUSIONS: These data quantify the contribution of bladder cancer risk factors to mutational burden and suggest different signature enrichments among never, former, and current smokers.
Assuntos
Genes Neoplásicos/genética , Sequenciamento de Nucleotídeos em Larga Escala , Mutação , Neoplasias da Bexiga Urinária/epidemiologia , Neoplasias da Bexiga Urinária/genética , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de RiscoRESUMO
APOBEC3A (A3A) and APOBEC3B (A3B) enzymes drive APOBEC-mediated mutagenesis. Identification of factors affecting the activity of these enzymes could help modulate mutagenesis and associated clinical outcomes. Here, we show that canonical and alternatively spliced A3A and A3B isoforms produce corresponding mutagenic and non-mutagenic enzymes. Increased expression of the mutagenic A3B isoform predicted shorter progression-free survival in bladder cancer. We demonstrate that the production of mutagenic vs. non-mutagenic A3B protein isoforms was considerably affected by inclusion/skipping of exon 5 in A3B. Furthermore, exon 5 skipping, resulting in lower levels of mutagenic A3B enzyme, could be increased in vitro. Specifically, we showed the effects of treatment with an SF3B1 inhibitor affecting spliceosome interaction with a branch point site in intron 4, or with splice-switching oligonucleotides targeting exon 5 of A3B. Our results underscore the clinical role of A3B and implicate alternative splicing of A3B as a mechanism that could be targeted to restrict APOBEC-mediated mutagenesis.
Assuntos
Processamento Alternativo , Biomarcadores Tumorais/genética , Citidina Desaminase/genética , Antígenos de Histocompatibilidade Menor/genética , Mutagênese , Proteínas/genética , Neoplasias da Bexiga Urinária/genética , Biomarcadores Tumorais/metabolismo , Citidina Desaminase/metabolismo , Compostos de Epóxi/farmacologia , Éxons , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Células HeLa , Células Hep G2 , Humanos , Isoenzimas , Macrolídeos/farmacologia , Antígenos de Histocompatibilidade Menor/metabolismo , Fosfoproteínas/antagonistas & inibidores , Fosfoproteínas/metabolismo , Intervalo Livre de Progressão , Proteínas/metabolismo , Fatores de Processamento de RNA/antagonistas & inibidores , Fatores de Processamento de RNA/metabolismo , Neoplasias da Bexiga Urinária/enzimologia , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/terapiaRESUMO
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes COVID-19, utilizes angiotensin-converting enzyme 2 (ACE2) for entry into target cells. ACE2 has been proposed as an interferon-stimulated gene (ISG). Thus, interferon-induced variability in ACE2 expression levels could be important for susceptibility to COVID-19 or its outcomes. Here, we report the discovery of a novel, transcriptionally independent truncated isoform of ACE2, which we designate as deltaACE2 (dACE2). We demonstrate that dACE2, but not ACE2, is an ISG. In The Cancer Genome Atlas, the expression of dACE2 was enriched in squamous tumors of the respiratory, gastrointestinal and urogenital tracts. In vitro, dACE2, which lacks 356 amino-terminal amino acids, was non-functional in binding the SARS-CoV-2 spike protein and as a carboxypeptidase. Our results suggest that the ISG-type induction of dACE2 in IFN-high conditions created by treatments, an inflammatory tumor microenvironment or viral co-infections is unlikely to increase the cellular entry of SARS-CoV-2 and promote infection.
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Enzima de Conversão de Angiotensina 2/metabolismo , Interferons/metabolismo , Vírus de RNA/fisiologia , Receptores de Coronavírus/metabolismo , SARS-CoV-2/metabolismo , Enzima de Conversão de Angiotensina 2/química , Enzima de Conversão de Angiotensina 2/genética , Carcinoma de Células Escamosas/enzimologia , Carcinoma de Células Escamosas/genética , Linhagem Celular , Indução Enzimática , Perfilação da Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Humanos , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Receptores de Coronavírus/genética , Mucosa Respiratória/metabolismo , Mucosa Respiratória/virologia , Glicoproteína da Espícula de Coronavírus/metabolismoRESUMO
BACKGROUND: The interferon lambda 4 gene (IFNL4) regulates immune responses by controlling the production of IFNλ4, a type III interferon. We hypothesised that IFNλ4 could play a role in infection clearance or alloreactivity in patients with acute leukaemia who received a myeloablative 10/10 HLA-matched haematopoietic stem-cell transplantation (HSCT). Therefore, we aimed to assess the association between recipient and donor IFNL4 genotype with post-HSCT survival outcomes in patients with acute leukaemia. METHODS: We did a two-stage retrospective cohort study using the Center for International Blood and Marrow Transplant Research (CIBMTR) repository and database, in which nearly all patients underwent the procedure in the USA. We included patients with acute myeloid leukaemia or acute lymphocytic leukaemia, who received a HSCT at any age from an unrelated 10/10 HLA-matched donor, with a myeloablative conditioning regimen, between Jan 1, 2000, and Dec 31, 2008, and had a pre-HSCT recipient or donor blood sample available. The discovery dataset included patients from an existing National Cancer Institute (NCI) cohort of the CIBMTR database, in which donor and recipient IFNL4 polymorphisms (rs368234815, rs12979860, and rs117648444) were genotyped with TaqMan assays. According to their genotype, donors and recipients were categorised into IFNL4-positive, if they had at least one copy of the allele that supports the production of IFNλ4, or IFNL4-null for the analyses. The findings were independently validated with patients from the DISCOVeRY-BMT cohort (validation dataset) with existing Illumina array genotype data. We also did a combined analysis using data from patients included in both the NCI and DISCOVeRY-BMT cohorts. FINDINGS: We assessed 404 patients (who had a HSCT from Jan 9, 2004, to Dec 26, 2008) in the discovery dataset and 1245 patients in the validation dataset (HSCT Jan 7, 2000, to Dec 26, 2008). The combined analysis included 1593 overlapping participants in both cohorts. Donor, but not recipient IFNL4-positive genotype was associated with increased risk of non-relapse mortality (HR 1·60, 95% CI 1·23-2·10; p=0·0005 in the discovery dataset; 1·22, 1·05-1·40; p=0·0072 in the validation dataset; and 1·27, 1·12-1·45; p=0·0001 in the combined dataset). Associations with post-HSCT overall survival were as follows: HR 1·24, 95% CI 1·02-1·51; p=0·034 in the discovery dataset; 1·10, 0·98-1·20; p=0·10 in the validation dataset; and 1·11, 1·02-1·22; p=0·018 in the combined dataset. INTERPRETATION: Prioritising HSCT donors with the IFNL4-null genotype might decrease non-relapse mortality and improve overall survival without substantially limiting the donor pool. If these findings are validated, IFNL4 genotype could be added to the donor selection algorithm. FUNDING: The National Cancer Institute Intramural Research Program. For full funding list see Acknowledgments.
Assuntos
Transplante de Células-Tronco Hematopoéticas , Interleucinas/genética , Leucemia Mieloide Aguda/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Adulto , Feminino , Genótipo , Transplante de Células-Tronco Hematopoéticas/mortalidade , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidade , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Estudos Retrospectivos , Resultado do Tratamento , Doadores não Relacionados , Adulto JovemRESUMO
Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), which causes COVID-19, utilizes angiotensin-converting enzyme 2 (ACE2) for entry into target cells. ACE2 has been proposed as an interferon-stimulated gene (ISG). Thus, interferon-induced variability in ACE2 expression levels could be important for susceptibility to COVID-19 or its outcomes. Here, we report the discovery of a novel, primate-specific isoform of ACE2, which we designate as deltaACE2 (dACE2). We demonstrate that dACE2, but not ACE2, is an ISG. In vitro, dACE2, which lacks 356 N-terminal amino acids, was non-functional in binding the SARS-CoV-2 spike protein and as a carboxypeptidase. Our results reconcile current knowledge on ACE2 expression and suggest that the ISG-type induction of dACE2 in IFN-high conditions created by treatments, inflammatory tumor microenvironment, or viral co-infections is unlikely to affect the cellular entry of SARS-CoV-2 and promote infection.
RESUMO
Long noncoding RNAs (lncRNA) have been implicated in many diseases, including cancer. Although these disease-associated effects have been mostly attributed to the ability of lncRNAs to function as regulatory noncoding transcripts, there is growing evidence that lncRNAs may also encode functional micropeptides. In the current issue of Cancer Research, Wu and colleagues report a micropeptide encoded by a Y chromosome-linked lncRNA that may explain the higher incidence of esophageal cancer in male smokers. Furthermore, this report provides broader insights related to the molecular epidemiology of male-dominant and smoking-driven cancers and may also help explain some cancer-related associations with mosaic Y chromosome loss.See related article by Wu et al., p. 2790.
Assuntos
Fumar Cigarros , Neoplasias Esofágicas , RNA Longo não Codificante , Carcinoma de Células Escamosas do Esôfago , Humanos , Masculino , RNA Longo não Codificante/genética , Fumaça , Cromossomo YRESUMO
Endemic Burkitt lymphoma (eBL) is an aggressive childhood B-cell lymphoma associated with Plasmodium falciparum (Pf) malaria and Epstein-Barr virus (EBV) infections. Variation in the Human Leukocyte Antigen (HLA) system is suspected to play a role, but assessments using less accurate serology-based HLA typing techniques in small studies yielded conflicting results. We studied 200 eBL cases and 400 controls aged 0-15 years enrolled in northern Uganda and typed by accurate high-resolution HLA sequencing methods. HLA results were analyzed at one- or two-field resolution. Odds ratios and 95% confidence intervals (aOR, 95% CI) for eBL risk associated with common HLA alleles versus alleles that were rare (<1%) or differed by <2% between the cases and controls as the reference category, were estimated using multiple logistic regression adjusting for age, sex, microgeography, region, malaria positivity and treatment history, and genetic variants associated with eBL. Compared to the controls, eBL cases had a lower frequency of HLA-A*02 (aOR = 0·59, 95% CI 0·38-0·91), HLA-B*41 (aOR = 0·36, 95% CI 0·13-1·00), and HLA-B*58 alleles (aOR = 0·59, 95% CI 0·36-0·97). eBL cases had a lower frequency of HLA-DPB1 homozygosity (aOR = 0·57, 95% CI 0·40-0·82) but a higher frequency of HLA-DQA1 homozygosity (aOR = 2·19, 95% CI 1·42-3·37). Our results suggest that variation in HLA may be associated with eBL risk.