RESUMO
Regulatory T (Treg) cells are important in maintaining self-tolerance and immune homeostasis. The Treg cell transcription factor Foxp3 works in concert with other co-regulatory molecules, including Eos, to determine the transcriptional signature and characteristic suppressive phenotype of Treg cells. Here, we report that the inflammatory cytokine interleukin-6 (IL-6) actively repressed Eos expression through microRNA-17 (miR-17). miR-17 expression increased in Treg cells in the presence of IL-6, and its expression negatively correlated with that of Eos. Treg cell suppressive activity was diminished upon overexpression of miR-17 in vitro and in vivo, which was mitigated upon co-expression of an Eos mutant lacking miR-17 target sites. Also, RNAi of miR-17 resulted in enhanced suppressive activity. Ectopic expression of miR-17 imparted effector-T-cell-like characteristics to Treg cells via the de-repression of genes encoding effector cytokines. Thus, miR-17 provides a potent layer of Treg cell control through targeting Eos and additional Foxp3 co-regulators.
Assuntos
Proteínas de Transporte/metabolismo , Colite/imunologia , Interleucina-6/metabolismo , MicroRNAs/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Linfócitos T Reguladores/imunologia , Animais , Proteínas de Transporte/genética , Células Cultivadas , Proteínas de Ligação a DNA , Modelos Animais de Doenças , Fatores de Transcrição Forkhead/metabolismo , Humanos , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Interleucina-6/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , MicroRNAs/genética , Proteínas do Tecido Nervoso/genética , Tolerância a Antígenos PrópriosRESUMO
BACKGROUND: Glioblastoma (GBM), a malignant brain tumor, has poor survival outcomes due to recurrence or drug resistance. We found that SH3GLB1 is a crucial factor for cells to evade temozolomide (TMZ) cytotoxicity through autophagy-mediated oxidative phosphorylation, which is associated with CD133 levels. Therefore, we propose that SH3GLB1 participate in the impact on tumor-initiating cells (TICs). METHODS: The parental, the derived resistant cell lines and their CD133+ cells were used, and the levels of the proteins were compared by western blotting. Then RNA interference was applied to observe the effects of the target protein on TIC-related features. Finally, in vitro transcription assays were used to validate the association between SH3GLB1 and CD133. RESULTS: The CD133+ cells from resistant cells with enhanced SH3GLB1 levels more easily survived cytotoxic treatment than those from the parental cells. Inhibition of SH3GLB1 attenuated frequency and size of spheroid formation, and the levels of CD133 and histone 4 lysine 5 (H4K5) acetylation can be simultaneously regulated by SH3GLB1 modification. The H4K5 acetylation of the CD133 promoter was later suggested to be the mediating mechanism of SH3GLB1. CONCLUSIONS: These data indicate that SH3GLB1 can regulate CD133 expression, suggesting that the protein plays a crucial role in TICs. Our findings on the effects of SH3GLB1 on the cells will help explain tumor resistance formation.
Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/metabolismo , Linhagem Celular Tumoral , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Interferência de RNA , Resistencia a Medicamentos Antineoplásicos/genéticaRESUMO
BACKGROUND: Sp1 is involved in the recurrence of glioblastoma (GBM) due to the acquirement of resistance to temozolomide (TMZ). Particularly, the role of Sp1 in metabolic reprogramming for drug resistance remains unknown. METHODS: RNA-Seq and mass spectrometry were used to analyze gene expression and metabolites amounts in paired GBM specimens (primary vs. recurrent) and in paired GBM cells (sensitive vs. resistant). ω-3/6 fatty acid and arachidonic acid (AA) metabolism in GBM patients were analyzed by targeted metabolome. Mitochondrial functions were determined by Seahorse XF Mito Stress Test, RNA-Seq, metabolome and substrate utilization for producing ATP. Therapeutic options targeting prostaglandin (PG) E2 in TMZ-resistant GBM were validated in vitro and in vivo. RESULTS: Among the metabolic pathways, Sp1 increased the prostaglandin-endoperoxide synthase 2 expression and PGE2 production in TMZ-resistant GBM. Mitochondrial genes and metabolites were obviously increased by PGE2, and these characteristics were required for developing resistance in GBM cells. For inducing TMZ resistance, PGE2 activated mitochondrial functions, including fatty acid ß-oxidation (FAO) and tricarboxylic acid (TCA) cycle progression, through PGE2 receptors, E-type prostanoid (EP)1 and EP3. Additionally, EP1 antagonist ONO-8713 inhibited the survival of TMZ-resistant GBM synergistically with TMZ. CONCLUSION: Sp1-regulated PGE2 production activates FAO and TCA cycle in mitochondria, through EP1 and EP3 receptors, resulting in TMZ resistance in GBM. These results will provide us a new strategy to attenuate drug resistance or to re-sensitize recurred GBM.
Assuntos
Glioblastoma , Apoptose/genética , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Ácidos Graxos/uso terapêutico , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Mitocôndrias , Temozolomida/farmacologiaRESUMO
LESSONS LEARNED: SCB01A is a novel microtubule inhibitor with vascular disrupting activity. This first-in-human study demonstrated SCB01A safety, pharmacokinetics, and preliminary antitumor activity. SCB01A is safe and well tolerated in patients with advanced solid malignancies with manageable neurotoxicity. BACKGROUND: SCB01A, a novel microtubule inhibitor, has vascular disrupting activity. METHODS: In this phase I dose-escalation and extension study, patients with advanced solid tumors were administered intravenous SCB01A infusions for 3 hours once every 21 days. Rapid titration and a 3 + 3 design escalated the dose from 2 mg/m2 to the maximum tolerated dose (MTD) based on dose-limiting toxicity (DLT). SCB01A-induced cellular neurotoxicity was evaluated in dorsal root ganglion cells. The primary endpoint was MTD. Safety, pharmacokinetics (PK), and tumor response were secondary endpoints. RESULTS: Treatment-related adverse events included anemia, nausea, vomiting, fatigue, fever, and peripheral sensorimotor neuropathy. DLTs included grade 4 elevated creatine phosphokinase (CPK) in the 4 mg/m2 cohort; grade 3 gastric hemorrhage in the 6.5 mg/m2 cohort; grade 2 thromboembolic event in the 24 mg/m2 cohort; and grade 3 peripheral sensorimotor neuropathy, grade 3 elevated aspartate aminotransferase, and grade 3 hypertension in the 32 mg/m2 cohort. The MTD was 24 mg/m2 , and average half-life was ~2.5 hours. The area under the curve-dose response relationship was linear. Nineteen subjects were stable after two cycles. The longest treatment lasted 24 cycles. SCB01A-induced neurotoxicity was reversible in vitro. CONCLUSION: The MTD of SCB01A was 24 mg/m2 every 21 days; it is safe and tolerable in patients with solid tumors.
Assuntos
Antineoplásicos , Neoplasias , Antineoplásicos/efeitos adversos , Relação Dose-Resposta a Droga , Humanos , Dose Máxima Tolerável , Microtúbulos , Neoplasias/tratamento farmacológico , Resultado do Tratamento , Moduladores de TubulinaRESUMO
Glioblastoma is the most common primary malignant brain tumor that is usually considered fatal even with treatment. This is often a result for tumor to develop resistance. Regarding the standard chemotherapy, the alkylating agent temozolomide is effective in disease control but the recurrence will still occur eventually. The mechanism of the resistance is various, and differs in terms of innate or acquired. To date, aberrations in O6-methylguanine-DNA methyltransferase are the clear factor that determines drug susceptibility. Alterations of the other DNA damage repair genes such as DNA mismatch repair genes are also known to affect the drug effect. Together these genes have roles in the innate resistance, but are not sufficient for explaining the mechanism leading to acquired resistance. Recent identification of specific cellular subsets with features of stem-like cells may have role in this process. The glioma stem-like cells are known for its superior ability in withstanding the drug-induced cytotoxicity, and giving the chance to repopulate the tumor. The mechanism is complicated to administrate cellular protection, such as the enhancing ability against reactive oxygen species and altering energy metabolism, the important steps to survive. In this review, we discuss the possible mechanism for these specific cellular subsets to evade cancer treatment, and the possible impact to the following treatment courses. In addition, we also discuss the possibility that can overcome this obstacle.
Assuntos
Antineoplásicos Alquilantes/farmacologia , Resistencia a Medicamentos Antineoplásicos , Glioblastoma/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Temozolomida/farmacologia , Animais , Glioblastoma/tratamento farmacológico , HumanosRESUMO
BACKGROUND: Gastric cancer (GC) is the third leading cause of cancer mortality globally and a molecularly heterogeneous disease. Identifying the driver pathways in GC progression is crucial to improving the clinical outcome. Recent studies identified ASPM (abnormal spindle-like microcephaly-associated) and FOXM1 (Forkhead box protein M1) as novel Wnt and cancer stem cell (CSC) regulators; their pathogenetic roles and potential crosstalks in GC remain unclarified. METHODS: The expression patterns of ASPM isoforms and FOXM1 were profiled in normal gastric epithelial and GC tissues. The functional roles of ASPM and FOXM1 in Wnt activity, cancer stemness and GC progression, and the underlying signaling processes were investigated. RESULTS: Approximately one third of GC cells upregulate the expression of ASPM isoform I (ASPMiI) in their cytoplasm; the tumors with a high ASPMiI positive score (≥ 10%) are associated with a poor prognosis of the patients. Mechanistically, the molecular interplay among FOXM1, ASPMiI and DVL3 was found to converge on ß-catenin to control the Wnt activity and the stemness property of GC cells. This multi-mode Wnt-regulatory module serves to reinforce Wnt signals in CSCs by transcriptional regulation (FOXM1-ASPM), protein-protein interactions (ASPMiI-DVL3-ß-catenin), and nuclear translocation (FOXM1-ß-catenin). CONCLUSIONS: This study illuminates a novel Wnt- and stemness-regulatory mechanism in GC cells and identifies a novel subset of FOXM1highASPMiIhigh GC with potential to guide Wnt- and stemness-related diagnostics and therapies.
Assuntos
Regulação Neoplásica da Expressão Gênica , Neoplasias Gástricas/genética , Linhagem Celular Tumoral , China , Proteína Forkhead Box M1/metabolismo , Humanos , Proteínas do Tecido Nervoso/metabolismo , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Análise de Sobrevida , Via de Sinalização WntRESUMO
Oral squamous cell carcinoma (SCC) is a prevalent malignant disease worldwide, especially so in Taiwan. Early- or even preclinical-stage detection is critical for reducing morbidity and mortality from oral SCC. Epidemiological and genome association studies are useful for identifying clinicopathological risk factors for preventive, diagnostic, and therapeutic approaches of oral SCC. For advanced oral SCC, effective treatments are critical to prolonging survival and enhancing quality of life. As oral SCC is characteristic of regional invasion with lymph node metastases, understanding the aggressive features of oral SCC, particularly in lymphangiogenesis, is essential for determining effective treatments. Emerging evidence has demonstrated that the tumor microenvironment (TME) plays a pivotal role in tumor growth, invasion, and metastases. Recent clinical successes in immune checkpoint inhibitors either alone or combined with chemotherapy have also supported the therapeutic value of immunotherapy in oral SCC. This review summarizes critical advances in basic knowledge of oral SCC from the perspective of clinicopathological risk factors, molecular tumorigenesis, and the TME. We also highlight our recent investigations on the microbiome, genome association studies, lymphangiogenesis, and immunomodulation in oral SCC. This review may provide new insights for oral SCC treatment by systematically interpreting emerging evidence from various preclinical and clinical studies.
Assuntos
Carcinogênese/patologia , Carcinoma de Células Escamosas/patologia , Linfangiogênese , Neoplasias Bucais/patologia , Microambiente Tumoral , Animais , Carcinoma de Células Escamosas/terapia , Humanos , Neoplasias Bucais/terapiaRESUMO
The phosphoinositide-3-kinase (PI3K) pathway has widely been considered as a potential therapeutic target for head and neck cancer (HNC); however, the application of PI3K inhibitors is often overshadowed by the induction of drug resistance with unknown mechanisms. In this study, PII3K inhibitor resistant cancer cells were developed by prolonged culturing of cell lines with BEZ235, a dual PI3K and mammalian target of rapamycin (mTOR) inhibitor. The drug resistant HNC cells showed higher IC50 of the proliferation to inhibitors specifically targeting PI3K and/or mTOR, as compared to their parental cells. These cells also showed profound resistance to drugs of other classes. Molecular analysis revealed persistent activation of phosphorylated AKT at threonine 308 in the drug resistant cells and increased expression of markers for tumor-initiating cells. Interestingly, increased intra-cellular ROS levels were observed in the drug resistant cells. Among anti-oxidant molecules, the expression of SOD2 was increased and was associated with the ALDH-positive tumor-initiating cell features. Co-incubation of SOD inhibitors and BEZ235 decreased the stemness feature of the cells in vitro, as shown by results of the spheroid formation assay. In conclusion, dysregulation of SOD2 might contribute to the profound resistance to PI3K inhibitors and the other drugs in HNC cells.
Assuntos
Resistencia a Medicamentos Antineoplásicos , Neoplasias de Cabeça e Pescoço/metabolismo , Imidazóis/farmacologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Quinolinas/farmacologia , Superóxido Dismutase/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Resistência a Múltiplos Medicamentos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Humanos , Células-Tronco Neoplásicas/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Fosforilação , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação para CimaRESUMO
BACKGROUND: Intratumor subsets with tumor-initiating features in glioblastoma are likely to survive treatment. Our goal is to identify the key factor in the process by which cells develop temozolomide (TMZ) resistance. METHODS: Resistant cell lines derived from U87MG and A172 were established through long-term co-incubation of TMZ. Primary tumors obtained from patients were maintained as patient-derived xenograft for studies of tumor-initating cell (TIC) features. The cell manifestations were assessed in the gene modulated cells for relevance to drug resistance. RESULTS: Among the mitochondria-related genes in the gene expression databases, superoxide dismutase 2 (SOD2) was a significant factor in resistance and patient survival. SOD2 in the resistant cells functionally determined the cell fate by limiting TMZ-stimulated superoxide reaction and cleavage of caspase-3. Genetic inhibition of the protein led to retrieval of drug effect in mouse study. SOD2 was also associated with the TIC features, which enriched in the resistant cells. The CD133+ specific subsets in the resistant cells exhibited superior superoxide regulation and the SOD2-related caspase-3 reaction. Experiments applying SOD2 modulation showed a positive correlation between the TIC features and the protein expression. Finally, co-treatment with TMZ and the SOD inhibitor sodium diethyldithiocarbamate trihydrate in xenograft mouse models with the TMZ-resistant primary tumor resulted in lower tumor proliferation, longer survival, and less CD133, Bmi-1, and SOD2 expression. CONCLUSION: SOD2 plays crucial roles in the tumor-initiating features that are related to TMZ resistance. Inhibition of the protein is a potential therapeutic strategy that can be used to enhance the effects of chemotherapy.
Assuntos
Antineoplásicos Alquilantes/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Glioblastoma/tratamento farmacológico , Células-Tronco Neoplásicas/efeitos dos fármacos , Superóxido Dismutase/administração & dosagem , Temozolomida/farmacologia , Animais , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Xenoenxertos/fisiopatologia , Humanos , Camundongos , Células-Tronco Neoplásicas/fisiologiaRESUMO
Epidermal growth factor receptor (EGFR) activation is a major cause of metastasis in such cancers as head and neck squamous cell carcinoma (HNSCC); however, whether the metabolic enzyme, pyruvate dehydrogenase kinase 1 (PDK1), mediates EGF-enhanced HNSCC metastasis remains unclear. Of interest, we found that EGF induced PDK1 expression in HNSCC. Tumor cell transformation induced by EGF was repressed by PDK1 knockdown, and the down-regulation of PDK1 expression or inhibition of its activity significantly blocked EGF-enhanced cell migration and invasion. In addition, depletion of PDK1 impeded EGF-enhanced binding of HNSCC cells to endothelial cells as well as the metastatic seeding of tumor cells in lungs. PDK1 depletion inhibited EGF-induced matrix metalloproteinase-1 (MMP-1), MMP-2, MMP-3, MMP-9, and fibronectin expression and Rac1/cdc42 activation. Furthermore, PDK1 overexpression induced MMP-1, MMP-2, MMP-3, MMP-9, and fibronectin expression and Rac1/cdc42 activation. Of interest, depletion of fibronectin inhibited PDK1-enhanced MMP-1-3 and MMP-9 expression as well as Rac1/cdc42 activation and tumor invasion. These results demonstrate that EGF-induced PDK1 expression enhances HNSCC metastasis via activation of the fibronectin signaling pathway. Inhibition of PDK1 may be a potential strategy for the treatment of EGFR-mediated HNSCC metastasis.-Hsu, J.-Y., Chang, J.-Y., Chang, K.-Y., Chang, W.-C., Chen B.-K. Epidermal growth factor-induced pyruvate dehydrogenase kinase 1 expression enhances head and neck squamous cell carcinoma metastasis via up-regulation of fibronectin.
Assuntos
Carcinoma de Células Escamosas/metabolismo , Fator de Crescimento Epidérmico/farmacologia , Fibronectinas/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/metabolismo , Humanos , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Invasividade Neoplásica/patologia , Piruvato Desidrogenase Quinase de Transferência de Acetil , Carcinoma de Células Escamosas de Cabeça e Pescoço , Ativação Transcricional/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacosRESUMO
It has been suggested that stress stimuli from the microenvironment maintain a subset of tumor cells with stem-like properties, including drug resistance. Here, we investigate whether Sp1, a stress-responsive factor, regulates stemness gene expression and if its inhibition sensitizes cancer cells to chemotherapy. Hydrogen peroxide- and serum deprivation-induced stresses were performed in glioblastoma (GBM) cells and patient-derived cells, and the effect of the Sp1 inhibitor mithramycin A (MA) on these stress-induced stem cells and temozolomide (TMZ)-resistant cells was evaluated. Sp1 and stemness genes were not commonly overexpressed in clinical GBM samples. However, their expression was highly induced by stress stimuli. Using MA, we demonstrated Sp1 as a critical stemness-related transcriptional factor protecting GBM cells against stress- and TMZ-induced death. Thus, Sp1 inhibition may prevent recurrence of malignant cells persisting after primary therapy.
Assuntos
Dacarbazina/análogos & derivados , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Fator de Transcrição Sp1/metabolismo , Animais , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/uso terapêutico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Dacarbazina/farmacologia , Dacarbazina/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/patologia , Humanos , Masculino , Camundongos , Camundongos SCID , Células-Tronco Neoplásicas/patologia , Estresse Oxidativo/efeitos dos fármacos , Temozolomida , Resultado do TratamentoRESUMO
BACKGROUND: Glioma stem-like cells (GSCs) are proposed to be responsible for high resistance in glioblastoma multiforme (GBM) treatment. In order to find new strategies aimed at reducing GSC stemness and improving GBM patient survival, we investigated the effects and mechanism of a histone deacetylases (HDACs) inhibitor, suberoylanilide hydroxamic acid (SAHA), since HDAC activity has been linked to cancer stem-like cell (CSC) abundance and properties. METHODS: Human GBM cell lines were plated in serum-free suspension cultures allowed for sphere forming and CSC enrichment. Subsequently, upon SAHA treatment, the stemness markers, cell proliferation, and viability of GSCs as well as cellular apoptosis and senescence were examined in order to clarify whether inhibition of GSCs occurs. RESULTS: We demonstrated that SAHA attenuated cell proliferation and diminished the expression stemness-related markers (CD133 and Bmi1) in GSCs. Furthermore, at high concentrations (more than 5 µM), SAHA triggered apoptosis of GSCs accompanied by increases in both activation of caspase 8- and caspase 9-mediated pathways. Interestingly, we found that a lower dose of SAHA (1 µM and 2.5 µM) inhibited GSCs via cell cycle arrest and induced premature senescence through p53 up-regulation and p38 activation. CONCLUSION: SAHA induces apoptosis and functions as a potent modulator of senescence via the p38-p53 pathway in GSCs. Our results provide a perspective on targeting GSCs via SAHA treatment, and suggest that SAHA could be used as a potent agent to overcome drug resistance in GBM patients.
Assuntos
Glioblastoma/tratamento farmacológico , Glioma/tratamento farmacológico , Inibidores de Histona Desacetilases/administração & dosagem , Ácidos Hidroxâmicos/administração & dosagem , Animais , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Glioblastoma/enzimologia , Glioblastoma/genética , Glioblastoma/patologia , Glioma/enzimologia , Glioma/genética , Glioma/patologia , Histona Desacetilases/biossíntese , Histona Desacetilases/genética , Humanos , Camundongos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/enzimologia , Células-Tronco Neoplásicas/patologia , Transdução de Sinais , Proteína Supressora de Tumor p53/genética , Vorinostat , Ensaios Antitumorais Modelo de Xenoenxerto , Proteínas Quinases p38 Ativadas por Mitógeno/genéticaRESUMO
Cisplatin (CDDP) is an important anti-cancer drug commonly used in various human cancers, including nasopharyngeal carcinoma (NPC). How to overcome the drug resistance of CDDP provides opportunities to improve clinical outcomes of NPC. O(6) -methylguanine-DNA methyltransferase (MGMT) has been well-characterized to be a therapeutic determinant of O(6) -alkylguanine alkylating drugs. However, the underlying mechanism and clinical relevance between MGMT and CDDP remain poorly defined in NPC. In this study, we showed that MGMT-proficient cells were highly resistant to the cytotoxic effects of CDDP as compared to MGMT-deficient cells. Further studies showed that the platinum level of DNA after CDDP exposure was significantly lower in MGMT-proficient cells than in MGMT-deficient cells. Host cell reactivation assay revealed that MGMT protected NPC cells from CDDP-induced DNA damage by enhancing DNA repair capacity. Importantly, we demonstrated for the first time that MGMT protein directly bound to CDDP-induced DNA damages. Subsequently, CDDP-bound MGMT protein became ubiquitinated and was degraded through ubiquitin-mediated proteasome system. We further analyzed the relationship between MGMT expression and clinical survivals in a cohort of 83 NPC patients. NPC patients who received CDDP-based concurrent chemoradiotherapy (CCRT), with high MGMT expression level, exhibited shorter progression-free survival (PFS; p = 0.022) and overall survival (OS; p = 0.015), than patients with low MGMT expression level. Furthermore, high MGMT expression level remained to be an independent prognostic factor for worse PFS (p = 0.01, hazard ratio 2.23) and OS (p = 0.018, hazard ratio 2.14). Our findings suggest that MGMT protein is important to determine the efficacy of CDDP in NPC.
Assuntos
Cisplatino/farmacologia , Adutos de DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/genética , O(6)-Metilguanina-DNA Metiltransferase/metabolismo , Compostos Organoplatínicos/farmacologia , Antineoplásicos/farmacologia , Carcinoma , Linhagem Celular Tumoral , Adutos de DNA/genética , Reparo do DNA/genética , Intervalo Livre de Doença , Humanos , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/patologia , PrognósticoRESUMO
Alcohol consumption is an established risk factor for head and neck cancer (HNC). The major carcinogen from alcohol is acetaldehyde, which may be produced by humans or by oral microorganisms through the metabolism of ethanol. To account for the different sources of acetaldehyde production, the current study examined the interplay between alcohol consumption, oral hygiene (as a proxy measure for the growth of oral microorganisms), and alcohol-metabolizing genes (ADH1B and ALDH2) in the risk of HNC. We found that both the fast (*2/*2) and the slow (*1/*1+ *1/*2) ADH1B genotypes increased the risk of HNC due to alcohol consumption, and this association differed according to the slow/non-functional ALDH2 genotypes (*1/*2+ *2/*2) or poor oral hygiene. In persons with the fast ADH1B genotype, the HNC risk associated with alcohol drinking was increased for those with the slow/non-functional ALDH2 genotypes. For those with the slow ADH1B genotypes, oral hygiene appeared to play an important role; the highest magnitude of an increased HNC risk in alcohol drinkers occurred among those with the worst oral hygiene. This is the first study to show that the association between alcohol drinking and HNC risk may be modified by the interplay between genetic polymorphisms of ADH1B and ALDH2 and oral hygiene. Although it is important to promote abstinence from or reduction of alcohol drinking to decrease the occurrence of HNC, improving oral hygiene practices may provide additional benefit.
Assuntos
Álcool Desidrogenase/genética , Consumo de Bebidas Alcoólicas/efeitos adversos , Aldeído Desidrogenase/genética , Carcinoma de Células Escamosas/etiologia , Neoplasias de Cabeça e Pescoço/etiologia , Higiene Bucal/efeitos adversos , Polimorfismo Genético/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Aldeído-Desidrogenase Mitocondrial , Carcinoma de Células Escamosas/epidemiologia , Estudos de Casos e Controles , Feminino , Seguimentos , Genótipo , Neoplasias de Cabeça e Pescoço/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prognóstico , Fatores de Risco , Fumar/efeitos adversos , Adulto JovemRESUMO
Despite the advances in diagnostic imaging and treatment modalities, the risk stratification and final outcomes in patients with nasopharyngeal carcinomas (NPC) still remain suboptimal. Through data mining from published transcriptomic database, topoisomerase IIα (TOP2A) was first identified as a differentially upregulated gene in NPC tissues, which implicates cell division via selective cleavage, rearrangement, and re-ligation of DNA strands. Given the roles of TOP2A in prognostication and in the frontline therapeutic regimen of common carcinomas, such as breast cancer, we explored TOP2A immunoexpression status and its associations with clinicopathological variables and survival in a well-defined cohort of NPC patients. TOP2A immunohistochemistry was retrospectively performed and analyzed using H-score method for biopsy specimens from 124 NPC patients who received standard treatment without distant metastasis at initial diagnosis. Those cases with H-score larger than the median value were construed as featuring TOP2A overexpression. The findings were correlated with the clinicopathological variables, disease-specific survival (DSS) and distant metastasis-free survival (DMFS). TOP2A overexpression was significantly associated with American Joint of Cancer Committee (AJCC) stages III-IV (p = 0.019) and univariately predictive of adverse outcomes for DSS (p = 0.0078) and DMFS (p = 0.0003). In the multivariate comparison, TOP2A overexpression remained prognostically independent to portend worse DSS (p = 0.047, hazard ratio = 1.732) and DMFS (p = 0.003, hazard ratio = 2.569), together with advanced AJCC stages III-IV. TOP2A expression is upregulated in a subset of NPCs and its increased immunoexpression significantly correlated with advanced stages and tumor aggressiveness, justifying the potentiality of TOP2A as a prognostic biomarker and a novel therapeutic target of NPC.
Assuntos
Antígenos de Neoplasias/genética , DNA Topoisomerases Tipo II/genética , Proteínas de Ligação a DNA/genética , Expressão Gênica , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma , Análise por Conglomerados , Feminino , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/patologia , Gradação de Tumores , Estadiamento de Neoplasias , Proteínas de Ligação a Poli-ADP-Ribose , Prognóstico , Adulto JovemRESUMO
Data mining in the public domain demonstrates that cyclin-dependent kinase 4 (CDK4) is highly expressed in nasopharyngeal carcinomas (NPC). Associated with cyclin-D, CDK4 phosphorylates and inactivates retinoblastoma (Rb) protein family members and mediates progression through the G1- to the S-phase of the cell cycle. Amplification and overexpression of CDK4 has been identified in various human malignancies. However, its expression and amplification has never been systemically evaluated in NPC. This study aimed to evaluate the amplification and expression status, correlation with clinicopathological features, and prognostic implications of CDK4 based on public domain dataset and in our well-defined cohort of NPC patients. The association between CDK4 transcript level and gene dosage was explored by analysis of an independent public domain dataset. We retrospectively assessed CDK4 immunoexpression in biopsies of 124 consecutive NPC patients devoid of initial distant metastasis and treated according to consistent guidelines. The results were correlated with clinicopathological features, local recurrence-free survival (LRFS), distant metastasis-free survival (DMeFS), and disease-specific survival (DSS). High levels of CDK4 protein were positively correlated with the T 3, 4 status (p = 0.024); N 2, 3 status (p < 0.001); and the American Joint Committee on Cancer stage 3, 4 (p < 0.001). Multivariate analysis suggested high CDK4 expression was an independent prognostic indicator of worse DMeFS (p = 0.001, hazard ratio (HR) = 3.226) and DSS (p = 0.037, HR = 1.838). Although CDK4 is frequently upregulated, its gene locus is very uncommonly amplified in NPC. CDK4 overexpression is mostly independent with gene amplification and represents a potential prognostic biomarker in NPC and may indicate tumor aggressiveness through cell cycle dysregulation.
Assuntos
Biomarcadores Tumorais/biossíntese , Quinase 4 Dependente de Ciclina/biossíntese , Neoplasias Nasofaríngeas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Carcinoma , Quinase 4 Dependente de Ciclina/genética , Intervalo Livre de Doença , Feminino , Amplificação de Genes , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/patologia , Estadiamento de Neoplasias , PrognósticoRESUMO
The molecular prognostic adjunct in patients with nasopharyngeal carcinomas (NPCs) still remains obscured. Through data mining from published transcriptomic database, alpha-methylacyl-CoA racemase (AMACR) was first identified as a differentially upregulated gene in NPC tissues, which is a key enzyme for isometric conversion of fatty acids entering the ß-oxidation. Given the roles of AMACR in prognostication and frontline therapeutic regimen of common carcinomas, such as prostate cancer, we explored AMACR immunoexpression status and its clinical significance in NPC patients. AMACR immunohistochemistry was retrospectively performed and analyzed using H-score for biopsy specimens from 124 NPC patients who received standard treatment without distant metastasis at initial diagnosis. Those cases with H-score larger than the median value were construed as featuring AMACR overexpression. The findings were correlated with the clinicopathological variables, disease-specific survival (DSS), distant metastasis-free survival (DMFS), and local recurrence-free survival (LRFS). Endogenous AMACR protein expressions were assessed by real-time reverse-transcription polymerase chain reaction (RT-PCR) and Western blotting in NPC cells and non-neoplastic mucosal cells. AMACR overexpression was significantly associated with increment of primary tumor status (P = 0.009) and univariately predictive of adverse outcomes for DSS, DMFS, and LRFS. In the multivariate comparison, AMACR overexpression still remained prognostically independent to portend worse DSS (P = 0.006, hazard ratio = 2.129), DMFS (P = 0.001, hazard ratio = 2.795), and LRFS (P = 0.041, hazard ratio = 2.009), together with advanced American Joint of Cancer Committee (AJCC) stages III-IV. Compared with non-neoplastic cells, both HONE1 and TW01 NPC cells demonstrated markedly increased AMACR expression. AMACR overexpression was identified as an important prognosticator and a potential therapeutic target in the future.
Assuntos
Neoplasias Nasofaríngeas/mortalidade , Racemases e Epimerases/fisiologia , Adulto , Idoso , Carcinoma , Linhagem Celular Tumoral , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/patologia , Estadiamento de Neoplasias , Prognóstico , Racemases e Epimerases/análise , Racemases e Epimerases/genética , Estudos RetrospectivosRESUMO
Despite recent improvements in the diagnosis and treatment, the final outcomes in patients with nasopharyngeal carcinomas (NPC) still remain suboptimal. Through data mining from published transcriptomic database with further bioinformatic validation, fibronectin (FN1) was identified as a differentially upregulated gene in NPC tissues, which implicates the transition from epithelial to mesenchymal phenotype (EMT) and promotes metastasis. Given the roles of fibronectin in risk stratification and in the frontline therapeutics of common carcinomas, such as renal cell cancer, we explored fibronectin immunoexpression status and its associations with clinicopathological variables and survival in a well-defined cohort of NPC patients. Fibronectin immunohistochemistry was retrospectively performed and analyzed using H-score for 124 biopsy specimens from NPC patients who received standard treatment without distant metastasis at initial diagnosis. Those cases with H-score higher than the median value were regarded as fibronectin overexpression. The findings were correlated with clinicopathological variables, EBV latent membrane protein 1 (LMP1) expression, disease-specific survival (DSS), distant metastasis-free survival (DMFS), and local recurrence-free survival (LRFS). Fibronectin overexpression was significantly associated with American Joint Committee on Cancer (AJCC) stages III-IV (p = 0.019) and LMP1 expression (p = 0.004), and univariately predictive of adverse outcomes for DSS, DMFS, and LRFS (all p < 0.0001). In the multivariate comparison, fibronectin overexpression still remained prognostically independent to portend worse DSS (p < 0.01, hazard ratio = 5.958), DMFS (p < 0.01, hazard ratio = 5.728), and LRFS (p < 0.01, hazard ratio = 5.411) together with a vanced AJCC stages III-IV. Fibronectin is upregulated in a subset of NPCs, and its increased immunoexpression significantly correlated with advanced features, justifying the potentiality of fibronectin as a theragnostic biomaker of NPC.