RESUMEN
MHC-I molecules expose the intracellular protein content on the cell surface, allowing T cells to detect foreign or mutated peptides. The combination of six MHC-I alleles each individual carries defines the sub-peptidome that can be effectively presented. We applied this concept to human cancer, hypothesizing that oncogenic mutations could arise in gaps in personal MHC-I presentation. To validate this hypothesis, we developed and applied a residue-centric patient presentation score to 9,176 cancer patients across 1,018 recurrent oncogenic mutations. We found that patient MHC-I genotype-based scores could predict which mutations were more likely to emerge in their tumor. Accordingly, poor presentation of a mutation across patients was correlated with higher frequency among tumors. These results support that MHC-I genotype-restricted immunoediting during tumor formation shapes the landscape of oncogenic mutations observed in clinically diagnosed tumors and paves the way for predicting personal cancer susceptibilities from knowledge of MHC-I genotype.
Asunto(s)
Presentación de Antígeno , Antígenos de Histocompatibilidad Clase I/genética , Antígenos de Histocompatibilidad Clase I/inmunología , Mutación , Neoplasias/inmunología , Línea Celular Tumoral , Simulación por Computador , Femenino , Células HeLa , Humanos , Masculino , Monitorización Inmunológica , ProteomaRESUMEN
Cystathionine beta-synthase (CBS) is a key enzyme of the trans-sulfuration pathway that converts homocysteine to cystathionine. Loss of CBS activity due to mutation results in CBS deficiency, an inborn error of metabolism characterized by extreme elevation of plasma total homocysteine (tHcy). C57BL6 mice containing either a homozygous null mutation in the cystathionine ß-synthase (Cbs-/- ) gene or an inactive human CBS protein (Tg-G307S Cbs-/- ) are born in mendelian numbers, but the vast majority die between 18 and 21 days of age due to liver failure. However, adult Cbs null mice that express a hypomorphic allele of human CBS as a transgene (Tg-I278T Cbs-/- ) show almost no neonatal lethality despite having serum tHcy levels similar to mice with no CBS activity. Here, we characterize liver and serum metabolites in neonatal Cbs+/- , Tg-G307S Cbs-/- , and Tg-I278T Cbs-/- mice at 6, 10, and 17 days of age to understand this difference. In serum, we observe similar elevations in tHcy in both Tg-G307S Cbs-/- and Tg-I278T Cbs-/- compared to control animals, but methionine is much more severely elevated in Tg-G307S Cbs-/- mice. Large scale metabolomic analysis of liver tissue confirms that both methionine and methionine-sulfoxide are significantly more elevated in Tg-G307S Cbs-/- animals, along with significant differences in several other metabolites including hexoses, amino acids, other amines, lipids, and carboxylic acids. Our data are consistent with a model that the neonatal lethality observed in CBS-null mice is driven by excess methionine resulting in increased stress on a variety of related pathways including the urea cycle, TCA cycle, gluconeogenesis, and phosphatidylcholine biosynthesis.
Asunto(s)
Cistationina betasintasa/fisiología , Modelos Animales de Enfermedad , Fallo Hepático/patología , Metaboloma , Mutación , Animales , Animales Recién Nacidos , Femenino , Fallo Hepático/etiología , Fallo Hepático/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , FenotipoRESUMEN
Receptor-interacting protein kinase 1 (RIPK1) regulates cell fate and proinflammatory signaling downstream of multiple innate immune pathways, including those initiated by TNF-α, TLR ligands, and IFNs. Genetic ablation of Ripk1 results in perinatal lethality arising from both RIPK3-mediated necroptosis and FADD/caspase-8-driven apoptosis. IFNs are thought to contribute to the lethality of Ripk1-deficient mice by activating inopportune cell death during parturition, but how IFNs activate cell death in the absence of RIPK1 is not understood. In this study, we show that Z-form nucleic acid binding protein 1 (ZBP1; also known as DAI) drives IFN-stimulated cell death in settings of RIPK1 deficiency. IFN-activated Jak/STAT signaling induces robust expression of ZBP1, which complexes with RIPK3 in the absence of RIPK1 to trigger RIPK3-driven pathways of caspase-8-mediated apoptosis and MLKL-driven necroptosis. In vivo, deletion of either Zbp1 or core IFN signaling components prolong viability of Ripk1-/- mice for up to 3 mo beyond parturition. Together, these studies implicate ZBP1 as the dominant activator of IFN-driven RIPK3 activation and perinatal lethality in the absence of RIPK1.
Asunto(s)
Muerte Celular/fisiología , Proteínas de Unión al ARN/metabolismo , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Apoptosis/fisiología , Caspasa 8/metabolismo , Línea Celular , Inflamación/metabolismo , Ratones , Ratones Endogámicos C57BL , Transducción de Señal/fisiologíaRESUMEN
Cystathionine ß-synthase (CBS) deficiency is a recessive inborn error of metabolism in which patients have extremely elevated plasma total homocysteine and have clinical manifestations in the vascular, visual, skeletal, and nervous systems. Homocysteine is an intermediary metabolite produced from the hydrolysis of S-adenosylhomocysteine (SAH), which is a by-product of methylation reactions involving the methyl-donor S-adenosylmethionine (SAM). Here, we have measured SAM, SAH, DNA and histone methylation status in an inducible mouse model of CBS deficiency to test the hypothesis that homocysteine-related phenotypes are caused by inhibition of methylation due to elevated SAH and reduced SAM/SAH ratio. We found that mice lacking CBS have elevated cellular SAH and reduced SAM/SAH ratios in both liver and kidney, but this was not associated with alterations in the level of 5-methylcytosine or various histone modifications. Using methylated DNA immunoprecipitation in combination with microarray, we found that of the 241 most differentially methylated promoter probes, 89 % were actually hypermethylated in CBS deficient mice. In addition, we did not find that changes in DNA methylation correlated well with changes in RNA expression in the livers of induced and uninduced CBS mice. Our data indicates that reduction in the SAM/SAH ratio, due to loss of CBS activity, does not result in overall hypomethylation of either DNA or histones.
Asunto(s)
Cistationina betasintasa/genética , Metilación de ADN/genética , Epigénesis Genética/genética , Homocistinuria/genética , Animales , Cistationina betasintasa/metabolismo , ADN/genética , Modelos Animales de Enfermedad , Epigenómica/métodos , Homocisteína/genética , Homocisteína/metabolismo , Homocistinuria/metabolismo , Riñón/metabolismo , Hígado/metabolismo , Ratones , S-Adenosilhomocisteína/metabolismo , S-Adenosilmetionina/metabolismoRESUMEN
In laboratory studies, acquired resistance to long-term antihormonal therapy in breast cancer evolves through two phases over 5 y. Phase I develops within 1 y, and tumor growth occurs with either 17ß-estradiol (E(2)) or tamoxifen. Phase II resistance develops after 5 y of therapy, and tamoxifen still stimulates growth; however, E(2) paradoxically induces apoptosis. This finding is the basis for the clinical use of estrogen to treat advanced antihormone-resistant breast cancer. We interrogated E(2)-induced apoptosis by analysis of gene expression across time (2-96 h) in MCF-7 cell variants that were estrogen-dependent (WS8) or resistant to estrogen deprivation and refractory (2A) or sensitive (5C) to E(2)-induced apoptosis. We developed a method termed differential area under the curve analysis that identified genes uniquely regulated by E(2) in 5C cells compared with both WS8 and 2A cells and hence, were associated with E(2)-induced apoptosis. Estrogen signaling, endoplasmic reticulum stress (ERS), and inflammatory response genes were overrepresented among the 5C-specific genes. The identified ERS genes indicated that E(2) inhibited protein folding, translation, and fatty acid synthesis. Meanwhile, the ERS-associated apoptotic genes Bcl-2 interacting mediator of cell death (BIM; BCL2L11) and caspase-4 (CASP4), among others, were induced. Evaluation of a caspase peptide inhibitor panel showed that the CASP4 inhibitor z-LEVD-fmk was the most active at blocking E(2)-induced apoptosis. Furthermore, z-LEVD-fmk completely prevented poly (ADP-ribose) polymerase (PARP) cleavage, E(2)-inhibited growth, and apoptotic morphology. The up-regulated proinflammatory genes included IL, IFN, and arachidonic acid-related genes. Functional testing showed that arachidonic acid and E(2) interacted to superadditively induce apoptosis. Therefore, these data indicate that E(2) induced apoptosis through ERS and inflammatory responses in advanced antihormone-resistant breast cancer.
Asunto(s)
Apoptosis/efectos de los fármacos , Neoplasias de la Mama/metabolismo , Estrés del Retículo Endoplásmico/efectos de los fármacos , Estradiol/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Proteínas Reguladoras de la Apoptosis/metabolismo , Ácido Araquidónico/metabolismo , Área Bajo la Curva , Proteína 11 Similar a Bcl2 , Caspasas Iniciadoras/metabolismo , Línea Celular Tumoral , Estrés del Retículo Endoplásmico/fisiología , Ácidos Grasos/biosíntesis , Femenino , Humanos , Proteínas de la Membrana/metabolismo , Análisis por Micromatrices , Pliegue de Proteína/efectos de los fármacos , Proteínas Proto-Oncogénicas/metabolismoRESUMEN
Cystathionine beta-synthase (CBS) deficiency is an inborn error of metabolism characterized by extremely elevated levels of plasma total homocysteine. The vast majority of CBS-deficient patients have missense mutations located in the CBS gene that result in the production of either misfolded or unstable protein. Here, we examine the effect of proteasome inhibitors on mutant CBS function using two different mouse models of CBS deficiency. These mice lack mouse CBS and express a missense mutant human CBS enzyme (either p.I278T or p.S466L) that has less than 5% of normal liver CBS activity, resulting in a 10-30-fold elevation in plasma homocysteine levels. We show that treatment of these mice with two different proteasome inhibitors can induce liver Hsp70, Hsp40, and Hsp27, increase levels of active CBS, and lower plasma homocysteine levels to within the normal range. However, response rates varied, with 100% (8/8) of the p.S466L animals showing correction, but only 38% (10/26) of the p.I278T animals. In total, our data show that treatment with proteostasis modulators can restore significant enzymatic activity to mutant misfolded CBS enzymes and suggests that they may be useful in treating certain types of genetic diseases caused by missense mutations.
Asunto(s)
Ácidos Borónicos/farmacología , Cistationina betasintasa/genética , Cistationina betasintasa/metabolismo , Homocistinuria/tratamiento farmacológico , Mutación Missense , Oligopéptidos/farmacología , Inhibidores de Proteasoma/farmacología , Pirazinas/farmacología , Animales , Bortezomib , Cistationina betasintasa/deficiencia , Femenino , Homocistinuria/enzimología , Homocistinuria/genética , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Inhibidores de Proteasoma/uso terapéutico , Pliegue de Proteína/efectos de los fármacosRESUMEN
Although estrogen and the enzymes responsible for its metabolism have been detected within the lung, the ability of this tissue to metabolize estrogen has not been demonstrated previously. The goal of this study was to characterize the profile of estrogen metabolites within the murine lung and to determine the effect of tobacco smoke exposure on metabolite levels. Use of liquid chromatography-tandem mass spectrometry led to the detection of three estrogens (E1, E2 and E3) and five estrogen metabolites (2-OHE1, 4-OHE1, 4-OHE2, 2-OMeE1 and 2-OMeE2) within the perfused lung, with 4-OHE1 being the most abundant species. Levels of 4-OHEs, carcinogenic derivatives produced primarily by cytochrome P450 1B1 (Cyp1b1), were 2-fold higher in females than males. Deletion of Cyp1b1 in females led to a dramatic reduction (21-fold) in 4-OHEs, whereas levels of 2-OHE1 and the putative protective estrogen metabolite 2-OMeE2 were increased (2.4- and 5.0-fold, respectively) (P = 0.01). Similar quantitative differences in estrogen metabolite levels were observed between Cyp1b1 null and wild-type males. Exposure of female mice to tobacco smoke for 8 weeks (2h per day, 5 days per week) increased the levels of 4-OHE1 (4-fold) and 2-OHE2 (2-fold) within the lung while reducing the total concentration of 2-OMeEs to 70% of those of unexposed controls. These data suggest that tobacco smoke accelerates the production of 4-OHEs within the lung; carcinogenic metabolites that could potentially contribute to lung tumor development. Thus, inhibition of CYP1B1 may represent a promising strategy for the prevention and treatment of lung cancer.
Asunto(s)
Hidrocarburo de Aril Hidroxilasas/metabolismo , Estrógenos/metabolismo , Pulmón/metabolismo , Nicotiana , Humo , Animales , Hidrocarburo de Aril Hidroxilasas/genética , Catecol O-Metiltransferasa/metabolismo , Citocromo P-450 CYP1B1 , Femenino , Genotipo , Neoplasias Pulmonares/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Factores SexualesRESUMEN
Untreated cystathionine beta-synthase (CBS) deficiency in humans is characterized by extremely elevated plasma total homocysteine (tHcy>200 microM), with thrombosis as the major cause of morbidity. Treatment with vitamins and diet leads to a dramatic reduction in thrombotic events, even though patients often still have severe elevations in tHcy (>80 microM). To understand the difference between extreme and severe hyperhomocysteinemia, we have examined two mouse models of CBS deficiency: Tg-hCBS Cbs(-/-) mice, with a mean serum tHcy of 169 microM, and Tg-I278T Cbs(-/-) mice, with a mean tHcy of 296 microM. Only Tg-I278T Cbs(-/-) animals exhibited strong biological phenotypes, including facial alopecia, osteoporosis, endoplasmic reticulum (ER) stress in the liver and kidney, and a 20% reduction in mean survival time. Metabolic profiling of serum and liver reveals that Tg-I278T Cbs(-/-) mice have significantly elevated levels of free oxidized homocysteine but not protein-bound homocysteine in serum and elevation of all forms of homocysteine and S-adenosylhomocysteine in the liver compared to Tg-hCBS Cbs(-/-) mice. RNA profiling of livers indicate that Tg-I278T Cbs(-/-) and Tg-hCBS Cbs(-/-) mice have unique gene signatures, with minimal overlap. Our results indicate that there is a clear pathogenic threshold effect for tHcy and bring into question the idea that mild elevations in tHcy are directly pathogenic.
Asunto(s)
Cistationina betasintasa/genética , Hiperhomocisteinemia/genética , Animales , Aorta/patología , Cistationina betasintasa/deficiencia , Modelos Animales de Enfermedad , Retículo Endoplásmico/metabolismo , Perfilación de la Expresión Génica , Regulación Enzimológica de la Expresión Génica/fisiología , Predisposición Genética a la Enfermedad , Hiperhomocisteinemia/sangre , Hiperhomocisteinemia/metabolismo , Hiperhomocisteinemia/patología , Hígado/metabolismo , Longevidad/genética , Ratones , Miocardio/patología , Análisis de Secuencia por Matrices de Oligonucleótidos , Osteoporosis/genética , Osteoporosis/metabolismo , Pliegue de ProteínaRESUMEN
Measurement of a tumor's overall genomic instability has gathered recent interest over the identification of specific genomic imbalances, as it may provide a more robust measure of tumor aggressiveness. Here we demonstrate the association of tumor genomic instability in the prediction of disease recurrence in patients with clinically localized clear cell renal cell carcinoma (ccRCC). Genomic copy number analysis was performed using SNP-based microarrays on tumors from 103 ccRCC patients. The number of copy number alterations (CNAs) for each tumor was calculated, and a genomic imbalance threshold (GIT) associated with high stage and high-grade disease was determined. Cox proportional hazards regression analyzes were performed to assess the effect of GIT on recurrence-free survival adjusting for known confounders. In the cohort, copy number losses in chromosome arms 3p, 14q, 6q, 9p, and 1p and gains of 5q and 7p/q were common. CNA burden significantly increased with increasing stage (p < .001) and grade (p < .001). The median CNA burden associated with patients presenting with advanced stage (IV) and high-grade (III/IV) tumors was ≥9, defining the GIT. On regression analysis, GIT was a superior predictor of recurrence (Hazard Ratio 4.44 [CI 1.36-14.48], p = .01) independent of stage, with similar results adjusting for grade. These findings were confirmed using an alternative measure of genomic instability, weighted Genomic Integrity Index. Our data support a key role for genomic instability in ccRCC progression. More importantly, we have identified a GIT (≥ 9 CNAs) that is a superior and independent predictor of disease recurrence in high-risk ccRCC patients.
Asunto(s)
Adenocarcinoma de Células Claras/mortalidad , Variaciones en el Número de Copia de ADN , Inestabilidad Genómica , Neoplasias Renales/mortalidad , Recurrencia Local de Neoplasia/mortalidad , Polimorfismo de Nucleótido Simple , Adenocarcinoma de Células Claras/genética , Adenocarcinoma de Células Claras/patología , Adulto , Anciano , Anciano de 80 o más Años , Variaciones en el Número de Copia de ADN/genética , Progresión de la Enfermedad , Femenino , Humanos , Neoplasias Renales/genética , Neoplasias Renales/patología , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/patología , Pronóstico , Tasa de SupervivenciaRESUMEN
Pleural malignant mesothelioma is a therapy-resistant cancer affecting the serosal lining of the thoracic cavity. Mutations/deletions of BAP1, CDKN2A, and NF2 are the most frequent genetic lesions in human malignant mesothelioma. We introduced various combinations of these deletions in the pleura of conditional knockout (CKO) mice, focusing on the contribution of Bap1 loss. While homozygous CKO of Bap1, Cdkn2a, or Nf2 alone gave rise to few or no malignant mesotheliomas, inactivation of Bap1 cooperated with loss of either Nf2 or Cdkn2a to drive development of malignant mesothelioma in approximately 20% of double-CKO mice, and a high incidence (22/26, 85%) of malignant mesotheliomas was observed in Bap1;Nf2;Cdkn2a (triple)-CKO mice. Malignant mesothelioma onset was rapid in triple-CKO mice, with a median survival of only 12 weeks, and malignant mesotheliomas from these mice were consistently high-grade and invasive. Adenoviral-Cre treatment of normal mesothelial cells from Bap1;Nf2;Cdkn2a CKO mice, but not from mice with knockout of one or any two of these genes, resulted in robust spheroid formation in vitro, suggesting that mesothelial cells from Bap1;Nf2;Cdkn2a mice have stem cell-like potential. RNA-seq analysis of malignant mesotheliomas from triple-CKO mice revealed enrichment of genes transcriptionally regulated by the polycomb repressive complex 2 (PRC2) and others previously implicated in known Bap1-related cellular processes. These data demonstrate that somatic inactivation of Bap1, Nf2, and Cdkn2a results in rapid, aggressive malignant mesotheliomas, and that deletion of Bap1 contributes to tumor development, in part, by loss of PRC2-mediated repression of tumorigenic target genes and by acquisition of stem cell potential, suggesting a potential avenue for therapeutic intervention. SIGNIFICANCE: Combinatorial deletions of Bap1, Nf2, and Cdkn2a result in aggressive mesotheliomas, with Bap1 loss contributing to tumorigenesis by circumventing PRC2-mediated repression of oncogenic target genes.
Asunto(s)
Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Neoplasias Pulmonares/patología , Mesotelioma/patología , Neurofibromina 2/genética , Neoplasias Pleurales/patología , Proteínas Supresoras de Tumor/genética , Ubiquitina Tiolesterasa/genética , Animales , Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Regulación Neoplásica de la Expresión Génica , Neoplasias Pulmonares/genética , Mesotelioma/genética , Mesotelioma Maligno , Ratones Noqueados , Neurofibromina 2/metabolismo , Neoplasias Pleurales/genética , Complejo Represivo Polycomb 2/genética , Complejo Represivo Polycomb 2/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Ubiquitina Tiolesterasa/metabolismoRESUMEN
CDK4/6 targeting is a promising therapeutic strategy under development for various tumor types. In this study, we used computational methods and The Cancer Genome Atlas dataset analysis to identify novel miRNAs that target CDK4/6 and exhibit potential for therapeutic development in colorectal cancer. The 3'UTR of CDK4/6 mRNAs are targeted by a family of miRNAs, which includes miR-6883-5p, miR-149*, miR-6785-5p, and miR-4728-5p. Ectopic expression of miR-6883-5p or miR-149* downregulated CDK4 and CDK6 levels in human colorectal cancer cells. RNA-seq analysis revealed an inverse relationship between the expression of CDK4/6 and miR-149* and intronic miRNA-6883-5p encoding the clock gene PER1 in colorectal cancer patient samples. Restoring expression of miR-6883-5p and miR-149* blocked cell growth leading to G0-G1 phase cell-cycle arrest and apoptosis in colorectal cancer cells. CDK4/6 targeting by miR-6883-5p and miR-149* could only partially explain the observed antiproliferative effects. Notably, both miRNAs synergized with the frontline colorectal cancer chemotherapy drug irinotecan. Further, they resensitized mutant p53-expressing cell lines resistant to 5-fluorouracil. Taken together, our results established the foundations of a candidate miRNA-based theranostic strategy to improve colorectal cancer management. Cancer Res; 77(24); 6902-13. ©2017 AACR.
Asunto(s)
Neoplasias del Colon/genética , Quinasa 4 Dependiente de la Ciclina/genética , Quinasa 6 Dependiente de la Ciclina/genética , Puntos de Control de la Fase G1 del Ciclo Celular/genética , MicroARNs/fisiología , Línea Celular Tumoral , Neoplasias del Colon/patología , Regulación Neoplásica de la Expresión Génica , Células HCT116 , Células HT29 , Humanos , Familia de Multigenes/fisiologíaRESUMEN
Resistance to hormonal therapies is a major clinical problem in the treatment of estrogen receptor α-positive (ERα+) breast cancers. Epigenetic marks, namely DNA methylation of cytosine at specific CpG sites (5mCpG), are frequently associated with ERα+ status in human breast cancers. Therefore, ERα may regulate gene expression in part via DNA methylation. This hypothesis was evaluated using a panel of breast cancer cell line models of antiestrogen resistance. Microarray gene expression profiling was used to identify genes normally silenced in ERα+ cells but derepressed upon exposure to the demethylating agent decitabine, derepressed upon long-term loss of ERα expression, and resuppressed by gain of ERα activity/expression. ERα-dependent DNA methylation targets (n = 39) were enriched for ERα-binding sites, basal-up/luminal-down markers, cancer stem cell, epithelial-mesenchymal transition, and inflammatory and tumor suppressor genes. Kaplan-Meier survival curve and Cox proportional hazards regression analyses indicated that these targets predicted poor distant metastasis-free survival among a large cohort of breast cancer patients. The basal breast cancer subtype markers LCN2 and IFI27 showed the greatest inverse relationship with ERα expression/activity and contain ERα-binding sites. Thus, genes that are methylated in an ERα-dependent manner may serve as predictive biomarkers in breast cancer. IMPLICATIONS: ERα directs DNA methylation-mediated silencing of specific genes that have biomarker potential in breast cancer subtypes. Mol Cancer Res; 15(2); 152-64. ©2016 AACR.
Asunto(s)
Neoplasias de la Mama/genética , Metilación de ADN , Transición Epitelial-Mesenquimal/genética , Receptor alfa de Estrógeno/genética , Células Madre Neoplásicas/fisiología , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Receptor alfa de Estrógeno/biosíntesis , Femenino , Regulación Neoplásica de la Expresión Génica , Silenciador del Gen , Humanos , Células MCF-7RESUMEN
Squamous cell carcinomas of the head and neck (SCCHN) affect anatomical sites including the oral cavity, nasal cavity, pharynx, and larynx. Laryngeal cancers are characterized by high recurrence and poor overall survival, and currently lack robust molecular prognostic biomarkers for treatment stratification. Using an algorithm for integrative clustering that simultaneously assesses gene expression, somatic mutation, copy number variation, and methylation, we for the first time identify laryngeal cancer subtypes with distinct prognostic outcomes, and differing from the non-prognostic laryngeal subclasses reported by The Cancer Genome Atlas (TCGA). Although most common laryngeal gene mutations are found in both subclasses, better prognosis is strongly associated with damaging mutations of the methyltransferases NSD1 and NSD2, with findings confirmed in an independent validation cohort consisting of 63 laryngeal cancer patients. Intriguingly, NSD1/2 mutations are not prognostic for nonlaryngeal SCCHN. These results provide an immediately useful clinical metric for patient stratification and prognostication.
Asunto(s)
N-Metiltransferasa de Histona-Lisina/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Neoplasias Laríngeas/enzimología , Mutación , Proteínas Nucleares/genética , Proteínas Represoras/genética , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Regulación Neoplásica de la Expresión Génica , Histona Metiltransferasas , N-Metiltransferasa de Histona-Lisina/metabolismo , Humanos , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Neoplasias Laríngeas/genética , Neoplasias Laríngeas/mortalidad , Masculino , Persona de Mediana Edad , Proteínas Nucleares/metabolismo , Pronóstico , Proteínas Represoras/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello/enzimología , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/mortalidadRESUMEN
Previous data from this group demonstrate that the murine lung metabolizes estrogen. Production of the putative carcinogen 4-hydroxyestrogen (4-OHE) is elevated within the lungs of female vs. male mice and accelerated by tobacco smoke. The goal of this study was to determine if the human lung metabolizes estrogen and evaluate the impact of tumor formation, smoke, sex and race/ethnicity on metabolism. Urine and lung tissue (normal, tumor) were obtained from 49 non-small cell lung cancer patients. Healthy postmenopausal Caucasian (n = 19) and Chinese (n = 20) American women (never-smokers) donated urine. Quantitative RT-PCR analyses indicate that multiple estrogen synthesis and metabolism genes are expressed in human bronchoalveolar cells. Estrogen and its metabolites were measured in lung tissue and urine using liquid chromatography/tandem mass spectrometry. Wilcoxon rank tests were used for statistical comparisons. E1, E2, E3 and estrogen metabolites 2-OHE1, 2-OHE2, 4-OHE1, 4-OHE2, 2-OME1 and 2-OME2 were detected at higher levels in tumor vs. adjacent normal tissue and in women vs. men (P < 0.05). The proportion of 4-OHEs was higher in tumors than in normal lung tissue (P < 0.05), and elevated in normal tissue from current- vs. never-smoking women (P = 0.006); similar trends were observed in urine. The proportion of 4-OHEs in the urine of postmenopausal Chinese American women was 1.8-fold higher than that of Caucasian women (P = 0.015). These data indicate that estrogen metabolites are present in the human lung. A shift towards 4-hydroxylation during lung tumorigenesis may contribute to the risk conferred by smoking, sex or race/ethnicity.
RESUMEN
The kinase RIPK3 is a key regulator of cell death responses to a growing number of viral and microbial agents. We have found that influenza A virus (IAV)-mediated cell death is largely reliant on RIPK3 and that RIPK3-deficient mice are notably more susceptible to lethal infection by IAV than their wild-type counterparts. Recent studies demonstrate that RIPK3 also participates in regulating gene transcription programs during host pro-inflammatory and innate-immune responses, indicating that this kinase is not solely an inducer of cell death and that RIPK3-driven transcriptional responses may collaborate with cell death in promoting clearance of IAV. Here, we carried out DNA microarray analyses to determine the contribution of RIPK3 to the IAV-elicited host transcriptional response. We report that RIPK3 does not contribute significantly to the RLR-activated transcriptome or to the induction of type I IFN genes, although, interestingly, IFN-ß production at a post-transcriptional step was modestly attenuated in IAV-infected ripk3-/- fibroblasts. Overall, RIPK3 regulated the expression of <5% of the IAV-induced transcriptome, and no genes were found to be obligate RIPK3 targets. IFN-ß signaling was also found to be largely normal in the absence of RIPK3. Together, these results indicate that RIPK3 is not essential for the host antiviral transcriptional response to IAV in murine fibroblasts.
Asunto(s)
Proteína 58 DEAD Box/metabolismo , Fibroblastos/virología , Virus de la Influenza A/metabolismo , Virus de la Influenza A/patogenicidad , Interferón Tipo I/metabolismo , Interferón beta/metabolismo , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismo , Animales , Proteína 58 DEAD Box/genética , Femenino , Fibroblastos/metabolismo , Interferón Tipo I/genética , Interferón beta/genética , Masculino , Ratones , Análisis de Secuencia por Matrices de Oligonucleótidos , Proteína Serina-Treonina Quinasas de Interacción con Receptores/genética , Transducción de Señal/genética , Transducción de Señal/fisiología , Replicación Viral/genética , Replicación Viral/fisiologíaRESUMEN
PURPOSE: The purpose of this study was to identify patient characteristics that may be risk factors or markers of susceptibility to adverse treatment effects in cancer Phase I and II clinical trials. PATIENTS AND METHODS: A total of 459 patients enrolled in 23 therapeutic Phase I and II studies at the Fox Chase Cancer Center were included in the analysis. Patient-specific characteristics, medical and treatment history, doses of experimental agents, and graded toxicities were extracted from case report forms. We developed a novel summary measure, the toxicity index (TI), to better discriminate patients on the basis of their overall toxicity experiences. Mixed model ANOVA was used to model TI on the basis of data from all trials using a specific agent. Generalized estimating equations in the context of binary logistic regression were used to model dose-limiting toxicity. RESULTS: Seventeen pretreatment factors, including performance status, alkaline phosphatase, total bilirubin, serum creatinine, and tobacco use, emerged as significant predictors of toxicity as defined by dose-limiting toxicity or TI. Unexpectedly, dose was not always a predictor of toxicity. Even for values within the normal range, the TI identified serum bilirubin and alkaline phosphatase as predictors of toxicity after treatment with docetaxel and alkaline phosphatase as a predictor for toxicity after treatment with irinotecan. CONCLUSIONS: Independent of dose, certain pretreatment characteristics, including measures of organ function that are in the normal range, were found to be predictors of treatment toxicity. Because of its sensitivity to differences in overall toxicity, the TI should prove to be a useful tool for identifying predictors of chemotherapy-related toxicity.
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Antineoplásicos/uso terapéutico , Ensayos Clínicos Fase I como Asunto , Ensayos Clínicos Fase II como Asunto , Neoplasias/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Análisis de Varianza , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Biomarcadores/sangre , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Valor Predictivo de las PruebasRESUMEN
The epigenetic alteration of aberrant hypermethylation in the promoter CpG island of a gene is associated with repression of transcription. In neoplastic cells, aberrant hypermethylation is well described as a mechanism of allele inactivation of particular genes with a tumor suppressor function. To investigate the role of aberrant hypermethylation in the biology and progression of urothelial cancer, we examined 101 urothelial (transitional cell) carcinomas (UC), broadly representative of the disease at presentation, with no prior immunotherapy, chemotherapy or radiotherapy, by Infinium HM27 containing 14,495 genes. The genome-wide signature of aberrant promoter hypermethylation in UC consisted of 729 genes significant by a Wilcoxon test, hypermethylated in a CpG island within 1 kb of the transcriptional start site and unmethylated in normal urothelium from aged individuals. We examined differences in gene methylation between the two main groups of UC: the 75% that are superficial, which often recur but rarely progress, and the 25% with muscle invasion and poor prognosis. We further examined pairwise comparisons of the pathologic subgroups of high or low grade, invasive or non-invasive (pTa), and high grade superficial or low grade superficial UC. Pathways analysis indicated over-representation of genes involved in cell adhesion or metabolism in muscle-invasive UC. Notably, the TET2 epigenetic regulator was one of only two genes more frequently methylated in superficial tumors and the sole gene in low grade UC. Other chromatin remodeling genes, MLL3 and ACTL6B, also showed aberrant hypermethylation. The Infinium methylation value for representative genes was verified by pyrosequencing. An available mRNA expression data set indicated many of the hypermethylated genes of interest to be downregulated in UC. Unsupervised clustering of the most differentially methylated genes distinguished muscle invasive from superficial UC. After filtering, cluster analysis showed a CpG Island Methylator Phenotype (CIMP)-like pattern of widespread methylation in 11 (11%) tumors. Nine of these 11 tumors had hypermethylation of TET2. Our analysis provides a basis for further studies of hypermethylation in the development and progression of UC.
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Carcinoma de Células Transicionales/genética , Metilación de ADN , Regiones Promotoras Genéticas , Neoplasias Urológicas/genética , Urotelio/metabolismo , Actinas/genética , Actinas/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Transicionales/metabolismo , Carcinoma de Células Transicionales/patología , Proteínas Cromosómicas no Histona/genética , Proteínas Cromosómicas no Histona/metabolismo , Islas de CpG , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Dioxigenasas , Epigénesis Genética , Femenino , Genoma Humano , Humanos , Masculino , Persona de Mediana Edad , Mutación Puntual , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Neoplasias Urológicas/metabolismo , Neoplasias Urológicas/patología , Urotelio/patologíaRESUMEN
Clear cell RCC is the most common, and more likely to metastasize, of the three main histological types of RCC. Pathologic stage is the most important prognostic indicator and nuclear grade can predict outcome within stages of localized RCC. Epithelial tumors are thought to accumulate a series of genetic and epigenetic changes as they progress through well-defined clinical and histopathological changes. MicroRNAs (miRNAs) are involved in the regulation of mRNA expression from many human genes and miRNA expression is dysregulated in cancer. To better understand the contribution of dysregulated miRNA expression to the progression and biology of ccRCC, we examined the differences in expression levels of 723 human miRNAs through a series of analyses by stage, grade, and disease progression status in a large series of 94 ccRCC. We found a consistent signature that included significant upregulation of miR-21-5p, 142-3p, let-7g-5p, let-7i-5p and 424-5p, as well as downregulation of miR-204-5p, to be associated with ccRCC of high stage, or high grade, or progression. Discrete signatures associated with each of stage, grade, or progression were also identified. The let-7 family was significantly downregulated in ccRCC compared with normal renal parenchyma. Expression of the 6 most significantly differentially expressed miRNAs between ccRCC was verified by stem-loop qRT-PCR. Pathways predicted as targets of the most significantly dysregulated miRNAs included signaling, epithelial cancers, metabolism, and epithelial to mesenchymal transition. Our studies help to further elucidate the biology underlying the progression of ccRCC and identify miRNAs for potential translational application.
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Carcinoma de Células Renales/metabolismo , Neoplasias Renales/metabolismo , MicroARNs/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Carcinoma de Células Renales/genética , Carcinoma de Células Renales/patología , Progresión de la Enfermedad , Transición Epitelial-Mesenquimal , Femenino , Humanos , Neoplasias Renales/genética , Neoplasias Renales/patología , Masculino , MicroARNs/genética , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Transducción de Señal , Análisis de Matrices TisularesRESUMEN
OBJECTIVE: The gene encoding the methionine salvage pathway methylthioadenosine phosphorylase (MTAP) is a tumor suppressor gene that is frequently inactivated in a wide variety of human cancers. In this study, we have examined if heterozygosity for a null mutation in Mtap (Mtap(lacZ)) could accelerate tumorigenesis development in two different mouse cancer models, Eµ-myc transgenic and Pten(+/-) . METHODS: Mtap Eµ-myc and Mtap Pten mice were generated and tumor-free survival was monitored over time. Tumors were also examined for a variety of histological and protein markers. In addition, microarray analysis was performed on the livers of Mtap(lacZ/+) and Mtap (+/+) mice. RESULTS: Survival in both models was significantly decreased in Mtap(lacZ/+) compared to Mtap(+/+) mice. In Eµ-myc mice, Mtap mutations accelerated the formation of lymphomas from cells in the early pre-B stage, and these tumors tended to be of higher grade and have higher expression levels of ornithine decarboxylase compared to those observed in control Eµ-myc Mtap(+/+) mice. Surprisingly, examination of Mtap status in lymphomas in Eµ-myc Mtap(lacZ/+) and Eµ-myc Mtap(+/+) animals did not reveal significant differences in the frequency of loss of Mtap protein expression, despite having shorter latency times, suggesting that haploinsufficiency of Mtap may be playing a direct role in accelerating tumorigenesis. Consistent with this idea, microarray analysis on liver tissue from age and sex matched Mtap(+/+) and Mtap(lacZ/+) animals found 363 transcripts whose expression changed at least 1.5-fold (P<0.01). Functional categorization of these genes reveals enrichments in several pathways involved in growth control and cancer. CONCLUSION: Our findings show that germline inactivation of a single Mtap allele alters gene expression and enhances lymphomagenesis in Eµ-myc mice.
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Carcinogénesis/genética , Carcinogénesis/patología , Mutación de Línea Germinal , Proteínas Asociadas a Microtúbulos/fisiología , Fosfohidrolasa PTEN/fisiología , Proteínas Proto-Oncogénicas c-myc/fisiología , Animales , Humanos , Ratones , Ratones Transgénicos , Tasa de Supervivencia , TranscriptomaRESUMEN
The majority of renal cell carcinoma (RCC) is now incidentally detected and presents as small renal masses (SRMs) defined as ≤ 4 cm in size. SRMs are heterogeneous comprising several histological types of RCC each with different biology and behavior, and benign tumors mainly oncocytoma. The varied prognosis of the different types of renal tumor has implications for management options. A key epigenetic alteration involved in the initiation and progression of cancer is aberrant methylation in the promoter region of a gene. The hypermethylation is associated with transcriptional repression and is an important mechanism of inactivation of tumor suppressor genes in neoplastic cells. We have determined the genome-wide promoter methylation profiles of 47 pT1a and 2 pT1b clear cell, papillary or chromophobe RCC, 25 benign renal oncocytoma ≤ 4 cm and 4 normal renal parenchyma specimens by Infinium HumanMethylation27 beadchip technology. We identify gene promoter hypermethylation signatures that distinguish clear cell and papillary from each other, from chromophobe and oncocytoma, and from normal renal cells. Pairwise comparisons revealed genes aberrantly hypermethylated in a tumor type but unmethylated in normal, and often unmethylated in the other renal tumor types. About 0.4% to 1.7% of genes comprised the promoter methylome in SRMs. The Infinium methylation score for representative genes was verified by gold standard technologies. The genes identified as differentially methylated implicate pathways involved in metabolism, tissue response to injury, epithelial to mesenchymal transition (EMT), signal transduction and G-protein coupled receptors (GPCRs), cancer, and stem cell regulation in the biology of RCC. Our findings contribute towards an improved understanding of the development of RCC, the different biology and behavior of histological types, and discovery of molecular subtypes. The differential methylation signatures may have utility in early detection and particularly differential diagnosis for prognostic stratification as well as identify novel gene and pathway targets for therapeutic intervention.