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1.
Int Immunopharmacol ; 138: 112518, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-38917528

RESUMO

Lung carcinoma is a frequently encountered cancerous growth that affects the respiratory tract and has a high occurrence rate globally. In light of the ongoing worldwide health emergency, the significance of efficient therapeutic agents and strategies is of utmost importance. A meticulous control of the cell cycle is crucial for comprehending the pathophysiology and molecular causes of lung cancer, as well as for the formulation of efficacious therapeutic medicines. The mechanism by which cells synchronize cell cycle with cell survival and death is still not fully understood. In this study, we demonstrate that the halting of the cell cycle has a strong inhibitory impact on ferroptosis, a specific type of controlled cell death triggered by excessive lipid peroxidation at the membranes of cells. Ferroptosis is halted through the mechanism of cell cycle arrest, which involves the deposition of intracellular lipids mediated by diacylglycerol acyltransferase (DGAT). Excessive amounts of polyunsaturated fatty acids (PUFAs) are stored as triacylglycerols (TAGs) within inactive cells. As a result, inhibiting DGAT causes a rearrangement of PUFAs from TAGs to phospholipids and makes arrested cells more susceptible to ferroptosis. We demonstrate that certain lung cancer cells that are resistant to antimitotic drugs and have a slow-cycling behavior exhibit an increase in lipid droplets. Furthermore, we find that the growth of tumors resistant to 5-fluorouracil, lorlatinib, and docetaxel can be effectively suppressed by a combination treatment involving the use of ferroptosis inducers and DGAT inhibitors, which induces ferroptosis. Collectively, these findings demonstrate the involvement of cell cycle arrest in conferring resistance to ferroptosis and propose a potential therapeutic approach for addressing the challenge of slow-cycling malignancies that exhibit resistance to ferroptosis.


Assuntos
Pontos de Checagem do Ciclo Celular , Ferroptose , Peroxidação de Lipídeos , Neoplasias Pulmonares , Ferroptose/efeitos dos fármacos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Camundongos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto , Camundongos Nus , Piperazinas/farmacologia , Piperazinas/uso terapêutico , Células A549
2.
J Cardiovasc Pharmacol ; 83(3): 220-227, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38030133

RESUMO

ABSTRACT: To systematically evaluate the efficacy and safety of renin-angiotensin system inhibitors (RASIs) and angiotensin receptor neprilysin inhibitors in preventing the recurrence of atrial fibrillation after atrial fibrillation ablation, we have written this meta-analysis. We systematically searched randomized controlled trials or cohort studies on RASIs and angiotensin receptor neprilysin inhibitor-sacubitril/valsartan (SV) in preventing the recurrence of atrial fibrillation. Two researchers independently screened the literature, extracted the data, and assessed the risk of bias in the included studies. Afterward, the meta-analysis was performed using RevMan 5.3 software. This meta-analysis results showed that the recurrence rate of atrial fibrillation after ablation in subjects using RASIs was lower than that in subjects not using them [relative risk = 0.85, 95% confidence interval (CI) (0.72-0.99), P = 0.03]; the recurrence rate in subjects using SV was lower than that in subjects using RASIs [RR= 0.50, 95% CI (0.37-0.68), P < 0.00001]. These results show that both the use of RASIs and SV can prevent the recurrence of after atrial fibrillation ablation, among which the use of SV is more effective.


Assuntos
Fibrilação Atrial , Insuficiência Cardíaca , Humanos , Antagonistas de Receptores de Angiotensina/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Compostos de Bifenilo , Combinação de Medicamentos , Inibidores Enzimáticos/uso terapêutico , Neprilisina , Receptores de Angiotensina , Sistema Renina-Angiotensina , Volume Sistólico , Tetrazóis/uso terapêutico , Valsartana/uso terapêutico
3.
Int. braz. j. urol ; 49(5): 535-563, Sep.-Oct. 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1506423

RESUMO

ABSTRACT Purpose: To compare the effectiveness and safety of marketed oral drugs for overactive bladder based on a systematic review and network meta-analysis approach. Methods: Pubmed, Embase, Web of Science, and the Cochrane Register of Clinical Trials databases were systematically searched. The search time frame was from database creation to June 2, 2022. Randomized controlled double-blind trials of oral medication for overactive bladder were screened against the protocol's entry criteria. Trials were evaluated for quality using the Cochrane Risk of Bias Assessment Tool, and data were statistically analyzed using Stata 16.0 software. Result: A total of 60 randomized controlled double-blind clinical trials were included involving 50,333 subjects. Solifenacin 10mg was the most effective in mean daily micturitions and incontinence episodes, solifenacin 5/10mg in mean daily urinary urgency episodes and nocturia episodes, fesoterodine 8mg in urgency incontinence episodes/d and oxybutynin 5mg in voided volume/micturition. In terms of safety, solifenacin 5mg, ER-tolterodine 4mg, mirabegron, vibegron and ER-oxybutynin 10mg all showed a better incidence of dry mouth, fesoterodine 4mg, ER-oxybutynin 10mg, tolterodine 2mg, and vibegron in the incidence of constipation. Compared to placebo, imidafenacin 0.1mg showed a significantly increased incidence in hypertension, solifenacin 10mg in urinary tract infection, fesoterodine 4/8mg and darifenacin 15mg in headache. Conclusion: Solifenacin showed better efficacy. For safety, most anticholinergic drugs were more likely to cause dry mouth and constipation, lower doses were better tolerated. The choice of drugs should be tailored to the patient's specific situation to find the best balance between efficacy and safety.

6.
Mol Cancer Ther ; 20(2): 274-283, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33293343

RESUMO

Liver kinase B1 (LKB1)-inactivated tumors are vulnerable to the disruption of pyrimidine metabolism, and leflunomide emerges as a therapeutic candidate because its active metabolite, A77-1726, inhibits dihydroorotate dehydrogenase, which is essential for de novo pyrimidine biosynthesis. However, it is unclear whether leflunomide inhibits LKB1-inactivated tumors in vivo, and whether its inhibitory effect on the immune system will promote tumor growth. Here, we carried out a comprehensive analysis of leflunomide treatment in various LKB1-inactivated murine xenografts, patient-derived xenografts, and genetically engineered mouse models. We also generated a mouse tumor-derived cancer cell line, WRJ388, that could metastasize to the lung within a month after subcutaneous implantation in all animals. This model was used to assess the ability of leflunomide to control distant metastasis. Leflunomide treatment shrank a HeLa xenograft and attenuated the growth of an H460 xenograft, a patient-derived xenograft, and lung adenocarcinoma in the immune-competent genetically engineered mouse models. Interestingly, leflunomide suppressed tumor growth through at least three different mechanisms. It caused apoptosis in HeLa cells, induced G1 cell-cycle arrest in H460 cells, and promoted S-phase cell-cycle arrest in WRJ388 cells. Finally, leflunomide treatment prevented lung metastasis in 78% of the animals in our novel lung cancer metastasis model. In combination, these results demonstrated that leflunomide utilizes different pathways to suppress the growth of LKB1-inactivated tumors, and it also prevents cancer metastasis at distant sites. Therefore, leflunomide should be evaluated as a therapeutic agent for tumors with LKB1 inactivation.


Assuntos
Inibidores Enzimáticos/uso terapêutico , Tolerância Imunológica/imunologia , Leflunomida/uso terapêutico , Neoplasias/tratamento farmacológico , Inibidores Enzimáticos/farmacologia , Humanos , Leflunomida/farmacologia , Metástase Neoplásica , Neoplasias/patologia
7.
Sci Rep ; 9(1): 6365, 2019 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-31019215

RESUMO

Flavonoids (FLAs) possess anti-cancer, anti-viral, anti-bacterial, and anti-oxidant properties. In this study, gelatin nanoparticles (GNPs) with controllable surface potential and diameter was prepared through a modified two-step desolvation. Two well-known flavonoids, namely, low-molecular weight Genistein (GEN) and high-molecular weight Icariin (ICA), were adsorbed onto the surface of GNPs (FLA@GNPs). The characteristics of GNPs and the main parameters affecting flavonoid adsorption were studied to evaluate the adsorption capacity and structural stability of FLA@GNPs. Furthermore, co-adsorption of GEN and ICA was detected. The adsorption mechanism of GNPs with FLA was further discussed. Results showed that the low-molecular weight GEN could be effectively adsorbed by GNPs, and their entrapment efficiencies were over 90% under optimized conditions. The total drug loading of the co-adsorbed FLA@GNPs was significantly higher than that of the single drug loaded (GEN or ICA). GEN@GNPs could maintain its structural stability under acidic conditions (pH = 2) at room temperature (25 °C). This protective function enables both ICA and GEN to be bioactive at room temperature for at least 180 days. The characteristics of GNPs adsorption indicate that the hydrogen bonding theory of the combination of gelatin molecules with polyphenols cannot sufficiently explain the binding of GNPs with polyphenols. FLA@GNPs is a promising general-purpose gelatin-based co-loading preload structure with simplified operation and storage condition.

8.
Prostate ; 79(4): 370-378, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30488457

RESUMO

BACKGROUND: PSMA expression in the prostate epithelium is controlled by a cis-element, PSMA enhancer (PSME). PSME contains multiple binding sites for Sox proteins, and in this study, we identified Sox7 protein as a negative regulator of PSMA expression through its interaction with PSME. METHODS: The statistical correlation between Sox7 and PSMA mRNA expression was evaluated using five prostate cancer studies from cBioportal. In vitro and in vivo interaction between Sox7 and PSME was evaluated by chromatin immunoprecipitation (ChIP), electrophoretic mobility shift assay (EMSA), and luciferase reporter assay. Synthetic oligonucleotides were generated to define the sites in PSME that interact with Sox7 protein. Sox7 mutants were generated to identify the region of this protein required to regulate PSMA expression. Sox7 was also stably expressed in LNCaP/C4-2 and 22Rv1 cells to validate the regulation of PSMA expression by Sox7 in vivo. RESULTS: Sox7 mRNA expression negatively correlated with PSMA/FOLH1 and PSMAL/FOLH1B mRNA expression in Broad/Cornell, TCGA and MSKCC studies, but not in two studies containing only metastatic prostate tumors. PC-3 cells mostly expressed the 48.5 KDa isoform 2 of Sox7, and the depletion of this isoform did not restore PSMA expression. Ectopic expression of canonical, wild-type Sox7 in C4-2 and 22Rv1 cells suppressed PSMA protein expression. ChIP assay revealed that canonical Sox7 protein preferentially interacts with PSME in vivo, and EMSA identified the SOX box sites #2 and #4 in PSME as required for its interaction. Sox7 was capable of directly binding to PSME and suppressed PSME-mediated transcription. The NLS regions of Sox7, but not its ß-catenin interacting motif, are essential for this suppressing activity. Furthermore, restoration of wild-type Sox7 expression but not Sox7-NLS mutant in Sox7-null prostate cancer cell lines suppressed PSMA expression. CONCLUSIONS: The inactivation of canonical Sox7 is responsible for the upregulated expression of PSMA in non-metastatic prostate cancer.


Assuntos
Antígenos de Superfície/genética , Elementos Facilitadores Genéticos/fisiologia , Regulação Neoplásica da Expressão Gênica/fisiologia , Glutamato Carboxipeptidase II/genética , Próstata/metabolismo , Neoplasias da Próstata/metabolismo , Fatores de Transcrição SOXF/fisiologia , Sequência de Aminoácidos , Sequência de Bases , Sítios de Ligação , Linhagem Celular Tumoral , Humanos , Masculino , Neoplasias da Próstata/química , RNA Mensageiro/análise , Fatores de Transcrição SOXF/química , Via de Sinalização Wnt/fisiologia
9.
Lung Cancer ; 123: 36-43, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30089593

RESUMO

OBJECTIVE: We previously postulated that 2-deoxyglucose (2-DG) activates multiple pro-survival pathways through IGF1R to negate its inhibitory effect on glycolysis. Here, we evaluated whether IGF1R inhibitor synergizes with 2-DG to impede the growth of non-small cell lung cancer (NSCLC). MATERIALS AND METHODS: The activation of IGF1R signaling was assessed by the phosphorylation of IGF1R and its downstream target AKT using immunoblot. Drug dose response and combination index analyses were carried out according to the method of Chou and Talalay. Flow cytometry was used to evaluate cell cycle progression. Apoptosis was monitored by caspase-3/PARP cleavages or Annexin V staining. A subcutaneous xenograft model was used to assess this combination in vivo. RESULTS: 2-DG induces the phosphorylation of IGF1R in its kinase domain, which can be abolished by the IGF1R inhibitor BMS-754807. Furthermore, the combination of 2-DG and BMS-754807 synergistically inhibited the survival of several non-small cell lung cancer (NSCLC) cell lines both in vitro and in vivo. The mechanistic basis of this synergy was cell line-dependent, and LKB1-inactivated EKVX cells underwent apoptosis following treatment with a subtoxic dose of 2-DG and BMS-754807. For these cells, the restoration of LKB1 kinase activity suppressed apoptosis induced by this combination but enhanced G1 arrest. In H460 cells, the addition of 2-DG did not enhance the low level of apoptosis induced by BMS-754807. However, treatment with 0.75 µM of BMS-754807 resulted in the accumulation of H460 cells with 8n-DNA content without affecting cell density increases. Hence, H460 cells may escape BMS-754807-induced G2/M cell cycle arrest through polyploidy. The inclusion of 2-DG blocked formation of the 8n-DNA cell population and restored G2/M phase cell cycle arrest. CONCLUSION: The combination of 2-DG and IGF1R inhibitor BMS-754807 may be used to suppress the proliferation of NSCLC tumors through different mechanisms.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Desoxiglucose/metabolismo , Neoplasias Pulmonares/metabolismo , Receptores de Somatomedina/antagonistas & inibidores , Quinases Proteína-Quinases Ativadas por AMP , Animais , Apoptose/efeitos dos fármacos , Biomarcadores , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Desoxiglucose/farmacologia , Modelos Animais de Doenças , Sinergismo Farmacológico , Humanos , Camundongos , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/metabolismo , Pirazóis/farmacologia , Receptor IGF Tipo 1 , Triazinas/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Thorac Cancer ; 9(9): 1166-1173, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30058109

RESUMO

BACKGROUND: We evaluated topoisomerase I (TOPO1) expression in patients with small cell lung cancer (SCLC) and identified predictive factors for the efficacy of second-line topotecan chemotherapy. METHODS: We retrospectively evaluated the records of SCLC patients treated in our department from January 2007 to December 2016 who received second-line topotecan chemotherapy. Patients with archived tumor samples were enrolled. TOPO1 expression levels were evaluated by immunohistochemistry, and the relationships between TOPO1 expression, clinical factors, chemotherapy efficacy, and survival were analyzed. RESULTS: Of the 78 patients enrolled, 67 showed TOPO1 expression (85.9%). Patients were divided into strong (n = 43) or weak (n = 35) expression groups based on staining intensity. Disease control rates for topotecan were 39.5% and 14.3% in the strong and weak groups, respectively (P = 0.014). Second-line median progression-free survival was 2.2 and 2.0 months (P = 0.057), and median overall survival was 8.1 and 6.0 months (P = 0.199) in the strong and weak positive groups, respectively. Patients were also divided into sensitive (n = 47) and refractory (n = 31) disease groups according to the duration from the onset of first-line therapy to relapse. Median second-line progression-free survival was 2.2 and 1.8 months in the sensitive and refractory relapse groups, respectively (P = 0.005). CONCLUSIONS: TOPO1 expression was prevalent in SCLC patients. Strong expression was associated with an elevated disease control rate after second-line topotecan chemotherapy. Patients with sensitive disease that relapsed after first-line chemotherapy had better survival than refractory patients who received second-line topotecan chemotherapy.


Assuntos
DNA Topoisomerases Tipo I/genética , Expressão Gênica , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Carcinoma de Pequenas Células do Pulmão/genética , Inibidores da Topoisomerase I/uso terapêutico , Topotecan/uso terapêutico , Idoso , Biomarcadores Tumorais , DNA Topoisomerases Tipo I/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/diagnóstico , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Recidiva , Carcinoma de Pequenas Células do Pulmão/diagnóstico , Tomografia Computadorizada por Raios X , Inibidores da Topoisomerase I/administração & dosagem , Inibidores da Topoisomerase I/efeitos adversos , Topotecan/administração & dosagem , Topotecan/efeitos adversos
11.
Oncotarget ; 8(35): 59008-59022, 2017 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-28938614

RESUMO

MEK inhibition is potentially valuable in targeting KRAS-mutant non-small cell lung cancer (NSCLC). Here, we analyzed whether concomitant LKB1 mutation alters sensitivity to the MEK inhibitor selumetinib, and whether the metabolism drug phenformin can enhance the therapeutic effect of selumetinib in isogenic cell lines with different LKB1 status. Isogenic pairs of KRAS-mutant NSCLC cell lines A549, H460 and H157, each with wild-type and null LKB1, as well as genetically engineered mouse-derived cell lines 634 (krasG12D/wt/p53-/-/lkb1wt/wt) and t2 (krasG12D/wt/p53-/-/lkb1-/-) were used in vitro to analyze the activities of selumetinib, phenformin and their combination. Synergy was measured and potential mechanisms investigated. The in vitro findings were then confirmed in vivo using xenograft models. The re-expression of wild type LKB1 increased phospho-ERK level, suggesting that restored dependency on MEK->ERK->MAPK signaling might have contributed to the enhanced sensitivity to selumetinib. In contrast, the loss of LKB1 sensitized cells to phenformin. At certain combination ratios, phenformin and selumetinib showed synergistic activity regardless of LKB1 status. Their combination reduced phospho-ERK and S6 levels and induced potent apoptosis, but was likely through different mechanisms in cells with different LKB1 status. Finally, in xenograft models bearing isogenic A549 cells, we confirmed that loss of LKB1 confers resistance to selumetinib, and phenformin significantly enhances the therapeutic effect of selumetinib. Irrespective of LKB1 status, phenformin may enhance the anti-tumor effect of selumetinib in KRAS-mutant NSCLC. The dual targeting of MEK and cancer metabolism may provide a useful strategy to treat this subset of lung cancer.

12.
PLoS One ; 11(12): e0168793, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28033353

RESUMO

Tumor cells rely on aerobic glycolysis to generate ATP, namely the "Warburg" effect. 2-deoxyglucose (2-DG) is well characterized as a glycolytic inhibitor, but its effect on cellular signaling pathways has not been fully elucidated. Herein, we sought to investigate the effect of 2-DG on ERK function in lung cancer cells. We found that 2-DG inhibits ERK phosphorylation in a time and dose-dependent manner in lung cancer cells. This inhibition requires functional LKB1. LKB1 knockdown in LKB1 wildtype cells correlated with an increase in the basal level of p-ERK. Restoration of LKB1 in LKB1-null cells significantly inhibits ERK activation. Blocking AMPK function with AMPK inhibitor, AMPK siRNA or DN-AMPK diminishes the inhibitory effect of 2-DG on ERK, suggesting that 2-DG-induced ERK inhibition is mediated by LKB1/AMPK signaling. Moreover, IGF1-induced ERK phosphorylation is significantly decreased by 2-DG. Conversely, a subset of oncogenic mutants of K-Ras, the main upstream regulator of ERK, blocks 2-DG-induced LKB1/AMPK signaling. These findings reveal the potential cross-talk between LKB1/AMPK and ERK signaling and help to better understand the mechanism of action of 2-DG.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Desoxiglucose/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Neoplasias Pulmonares/patologia , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas ras/metabolismo , Quinases Proteína-Quinases Ativadas por AMP , Proteínas Quinases Ativadas por AMP/metabolismo , Linhagem Celular Tumoral , Ativação Enzimática/efeitos dos fármacos , Humanos , Fator de Crescimento Insulin-Like I/farmacologia , Mutação , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos
13.
Onco Targets Ther ; 9: 5693-5698, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27695347

RESUMO

PURPOSE: The purpose of this study was to observe the clinical efficacy and toxicity of cisplatin in combination with gemcitabine or Abraxane as first-line chemotherapy for stage III/IV non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: A total of 200 patients with advanced NSCLC, which was confirmed by pathology or cytology, were enrolled into our research by reviewing previous complete and retrievable medical records data of our hospital. A total of 100 patients were treated with gemcitabine (1,000 mg/m2, day 1 and day 8) in combination with cisplatin (75 mg/m2, days 1-3; GP group) and another 100 patients were treated with Abraxane (260 mg/m2, day 1) in combination with cisplatin (75 mg/m2, days 1-3; TP group). Twenty-one days were required to complete one cycle; at least two cycles were completed by each group. RESULTS: For the 100 patients in the GP group, the effective response rate (RR) was 27%, the disease control rate (DCR) was 63%, and the median progression-free survival (PFS) time was 8 months. For the 100 patients in the TP group, the RR was 52%, the DCR was 75%, and the median PFS was 20 months. There was significant difference in RR (P<0.001), but no significant difference in DSR and PFS (P>0.05). Common treatment-related adverse events were hematologic toxicity and gastrointestinal reaction. Hematologic toxicity mainly included decreased white blood cells and platelets. The differences between the two groups were statistically significant (P<0.05). Gastrointestinal reaction mainly included nausea and vomiting. There was no statistical significance between them (P=0.805). For the 85 patients with squamous carcinoma in the TP group, the RR was 60%, the DCR was 78%, and the median PFS was 7.5 months. For the 85 patients with squamous carcinoma in the GP group, the RR was 36%, the DCR was 62%, and the median PFS was 18.5 months. There was significant difference in RR (P=0.024), but no significant difference in DSR and PFS (P>0.05). For the 115 patients with adenocarcinoma in the TP group, the RR was 47%, the DCR was 73%, and the median PFS was 8 months. For the 115 patients with adenocarcinoma in the GP group, the RR was 20%, the DCR was 64%, and the median PFS was 20.5 months. There was significant difference in RR (P=0.003), but no significant difference in DCR and PFS (P>0.05). CONCLUSION: The efficacy of cisplatin in combination with Abraxane is better than that with gemcitabine in the treatment of NSCLC, and the treatment has less risk of hematologic toxicity.

14.
Oncotarget ; 7(3): 2519-31, 2016 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-26506235

RESUMO

We analyzed the mechanism underlying 5-aminoimidazole-4-carboxamide riboside (AICAR) mediated apoptosis in LKB1-null non-small cell lung cancer (NSCLC) cells. Metabolic profile analysis revealed depletion of the intracellular pyrimidine pool after AICAR treatment, but uridine was the only nucleotide precursor capable of rescuing this apoptosis, suggesting the involvement of RNA metabolism. Because half of RNA transcription in cancer is for pre-ribosomal RNA (rRNA) synthesis, which is suppressed by over 90% after AICAR treatment, we evaluated the role of TIF-IA-mediated rRNA synthesis. While the depletion of TIF-IA by RNAi alone promoted apoptosis in LKB1-null cells, the overexpression of a wild-type or a S636A TIF-IA mutant, but not a S636D mutant, attenuated AICAR-induced apoptosis. In LKB1-null H157 cells, pre-rRNA synthesis was not suppressed by AICAR when wild-type LKB1 was present, and cellular fractionation analysis indicated that TIF-IA quickly accumulated in the nucleus in the presence of a wild-type LKB1 but not a kinase-dead mutant. Furthermore, ectopic expression of LKB1 was capable of attenuating AICAR-induced death in AMPK-null cells. Because LKB1 promotes cell survival by modulating TIF-IA-mediated pre-rRNA synthesis, this discovery suggested that targeted depletion of uridine related metabolites may be exploited in the clinic to eliminate LKB1-null cancer cells.


Assuntos
Apoptose , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Proteínas Pol1 do Complexo de Iniciação de Transcrição/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Precursores de RNA/metabolismo , Uridina/metabolismo , Quinases Proteína-Quinases Ativadas por AMP , Western Blotting , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Ciclo Celular , Núcleo Celular , Proliferação de Células , Imunofluorescência , Humanos , Técnicas Imunoenzimáticas , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Fosforilação , Proteínas Pol1 do Complexo de Iniciação de Transcrição/genética , Proteínas Serina-Treonina Quinases/genética , Precursores de RNA/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Gênica , Células Tumorais Cultivadas
15.
Technol Cancer Res Treat ; 15(3): 509-16, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-25948322

RESUMO

Circulating tumor cells are low-frequency cells that are shed into the peripheral bloodstream from a primary solid tumor and/or metastasis. Although these cells were recognized initially in 1869, it is only in the past 2 decades that they have been isolated for use as a surrogate biomarker to monitor response to therapy, evaluate prognosis, detect tumor mutations, assist in selecting personalized medicine, and enable earlier cancer diagnosis.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias/patologia , Células Neoplásicas Circulantes/patologia , Humanos
16.
Lung Cancer ; 88(2): 131-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25769882

RESUMO

OBJECTIVES: The tumor suppressor LKB1 has recently been shown to be involved in the regulation of microtubule dynamics, thus cancer cells with inactivated LKB1 may have developed a means to overcome dysregulated microtubule functions, making them intrinsically resistant to microtubule targeting agents. Here, we generated isogenic LKB1-wild type and mutant non-small cell lung cancer (NSCLC) cell lines to evaluate the role of LKB1 in paclitaxel resistance. MATERIALS AND METHODS: SRB, flow cytometry and immunoblotting were used to assess cell proliferation and apoptosis in NSCLC cell lines after paclitaxel treatment. Expression of LKB1 was restored in LKB1-null cells by retrovirus infection and was reduced in LKB1-wild type cells by shRNA knock down. RESULTS AND CONCLUSION: The restoration of LKB1 in LKB1-null cells failed to promote paclitaxel-induced apoptosis in both p53-wild type and p53-mutant backgrounds, indicating that LKB1 was not required for paclitaxel-induced apoptosis. Interestingly, the re-establishment of LKB1 expression led to the up-regulation of class III beta-tubulin and MDR1 in EKVX cells. The up-regulation of MDR1 protein and transcripts in EKVX cells was specifically associated with the expression of wild-type LKB1 and mainly responsible for the increased cellular resistance to paclitaxel. However, the presence of LKB1 protein was not required to maintain this increased MDR1 expression even though there was no genetic amplification or promoter de-methylation of the ABCB1 locus in EKVX-LKB1-WT cells. These data suggest that LKB1 does not promote paclitaxel-induced apoptosis in most NSCLC cell lines. In contrast, in some NSCLC, the presence of LKB1 may facilitate increases in either MDR1 or class III beta-tubulin expression which can lead to paclitaxel resistance.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Pulmonares/tratamento farmacológico , Paclitaxel/farmacologia , Proteínas Serina-Treonina Quinases/genética , Regulação para Cima/genética , Quinases Proteína-Quinases Ativadas por AMP , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Apoptose/efeitos dos fármacos , Apoptose/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/genética , Células HEK293 , Humanos , Neoplasias Pulmonares/genética , Tubulina (Proteína)/genética , Regulação para Cima/efeitos dos fármacos
17.
Int J Clin Exp Med ; 8(10): 19460-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26770592

RESUMO

The etiology of lung cancer is still incompletely understood. Previous studies have suggested the association between IL-21 polymorphisms and autoimmune diseases, however, little is known about its role in lung cancer susceptibility. Here, we investigated the role of two SNPs of IL-21 gene in a cohort of non-small cell lung cancer (NSCLC) patients. A total of 128 NSCLC patients and 156 healthy controls were genotyped. Multivariate logistic regression was used to analyze the association between IL-21 polymorphisms and NSCLC risk. Our data showed that both rs907715 and rs2221903 were significantly associated with lung cancer susceptibility, and patients carrying rs907715A (P = 0.007, adjusted OR = 0.60, 95% CI = 0.42-0.87) or rs2221903G (P = 0.020, adjusted OR = 0.52, 95% CI = 0.30-0.90) allele had a decreased risk of NSCLC. Further study identified that the association between IL-21 polymorphisms and NSCLC risk was limited to lung adenocarcinoma. Haplotype analysis revealed that the AG (P = 0.006, OR = 0.072 95% CI = 0.011-0.451) and AA (P = 0.022, OR = 0.657, 95% CI = 0.458-0.941) haplotypes of rs907715/rs2221903 were associated with a decreased risk of NSCLC, whereas the GA (P = 0.0001, OR = 1.932, 95% CI = 1.378-2.710) haplotype was associated with an increased risk. In conclusion, our study demonstrates the association between IL-21 polymorphisms (rs907715 and rs2221903) and NSCLC risk in a Chinese Han population, indicating their potential role in lung cancer detection and treatment.

18.
Asian Pac J Cancer Prev ; 15(14): 5697-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25081688

RESUMO

OBJECTIVE: To investigate the optimal timing of radiotherapy with alternating/sequential radio-chemotherapy for limited-stage small cell lung cancer (LS-SCLC). METHODS: 91 patients with LS-SCLC were retrospectively analyzed and divided into two groups according to the number of chemotherapy cycles before radiotherapy. If the patient received radiotherapy after 3 cycles or fewer cycles of chemotherapy, classification was into the early group, if not, into the late group. All patients received 6 cycles of standard chemotherapy (EP/EC) and conventional radiotherapy (56 gy~ 60 gy/28 f ~30 f). RESULTS: The response rate (RR) of the early and late groups were 85.7% and 81.6%, respectively, with no significant difference (p>0.05). In contrast, the progression-free survival (PFS) in the early group was better than that in the late group (11.8 months vs 9.86 months), and the difference was significant (p<0.05). There was no significant difference between two groups in adverse reactions, which gastrointestinal irritation and bone marrow suppression being the most common (p>0.05). CONCLUSIONS: Radiotherapy after 3 cycles or fewer cycles of chemotherapy does not bring significant benefits for RR of patients with LS-SCLC, but it could significantly prolong their PFS without increase in adverse reactions.


Assuntos
Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/radioterapia , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Carcinoma de Pequenas Células do Pulmão/radioterapia , Neoplasias das Glândulas Suprarrenais/secundário , Adulto , Idoso , Neoplasias Ósseas/secundário , Neoplasias Encefálicas/secundário , Terapia Combinada , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estudos Retrospectivos , Carcinoma de Pequenas Células do Pulmão/mortalidade
19.
Thorac Cancer ; 5(1): 31-7, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26766969

RESUMO

BACKGROUND: This study was designed to detect the protein expression of epidermal growth factor receptor (EGFR) among serum, lymph node, and tumor tissues, and to discuss their relationship and clinical significance. We investigated whether EGFR levels in serum and lymph nodes could be used as an effective method for non-small cell lung cancer (NSCLC) to diagnose and assess clinical stage. METHODS: In 56 patients with NSCLC and 10 individuals with nonmalignant thoracic disease, we measured EGFR levels in serum using an enzyme immunoassay, and EGFR mRNA levels in lymph node and NSCLC tissues by quantitative real-time-polymerase chain reaction. We examined the correlation between them and with the clinical parameters. RESULTS: Serum EGFR levels substantially decreased after surgical treatment (P < 0.001). Serum EGFR levels were correlated with smoking, surgery, and pathological type after surgery (all P < 0.05). EGFR mRNA levels in lymph node and tumor tissues were correlated more closely with lymph node metastasis (P = 0.015. EGFR mRNA in tissues was higher than that of benign pulmonary diseases (P = 0.020). There was an obvious positive correlation among EGFR levels of serum and lymph node tissues (r = 0.764; P < 0.001), serum and tumor tissues (r = 0.616; P < 0.001), and lymph node and tumor tissues (r = 0.904; P < 0.001) in NSCLCs. CONCLUSION: The data suggest that detecting EGFR levels in serum and lymph node tissues could be a simple and effective method to diagnose and assess the clinical stage in patients with NSCLC.

20.
Biochem Biophys Res Commun ; 440(4): 604-10, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24099768

RESUMO

MicroRNAs (miRNAs) have emerged to play important roles in tumorigenesis and drug resistance of human cancer. Fewer studies were explored the roles of miR-92b on human lung cancer cell growth and resistance to cisplatin (CDDP). In this paper, we utilized real-time PCR to verify miR-92b was significantly up-regulated in non-small cell lung cancer (NSCLC) tissues compared to matched adjacent normal tissues. In vitro assay demonstrated that knock-down of miR-92b inhabits cell growth and sensitized the A549/CDDP cells to CDDP. Furthermore, we found miR-92b could directly target PTEN, a unique tumor suppressor gene, which was downregulated in lung cancer tissues compared to the matched adjacent normal tissues. These data indicate that the miR-92b play an oncogene roles by regulates cell growth, cisplatin chemosensitivity phenotype, and could serve as a novel potential maker for NSCLC therapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Cisplatino/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , MicroRNAs/fisiologia , PTEN Fosfo-Hidrolase/genética , Apoptose , Proliferação de Células , Humanos , MicroRNAs/genética , Regulação para Cima
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