Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 14.072
Filtrar
1.
Medicine (Baltimore) ; 100(36): e27017, 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34516491

RESUMO

RATIONALE: Metastatic gastric cancer patients with poor eastern cooperative oncology group performance status (PS) (≥3) were lack of effective anti-tumor strategies. They always lived with poor PS, severe and multiple symptoms, and usually resulted in extremely limited survival time. Herein, we reported a patient diagnosed with gastric cancer metastasized to multiple bones, along with lymphangitis carcinomatosa in lungs, harboring Her-2 and c-MET amplification with poor PS, positively responded to combinational therapy with trastuzumab and crizotinib. PATIENT CONCERNS: The patient complained of persistent cough and fatigue for 2 months, otherwise, she denied smoking, alcohol history, or any other medical or family history. DIAGNOSIS: With the biopsy results from gastroscopy, as well as computer tomography for chest and abdomen, the patient was diagnosed as gastric adenocarcinoma, with metastasis on lungs, left adrenal gland, retroperitoneal lymph nodes, and multiple bones. INTERVENTIONS: Because of the poor PS (PS = 3), as well as Her-2 and c-MET amplification, the patient received combination treatment with trastuzumab and crizotinib as salvage strategy. OUTCOMES: After 2 months' exposure of trastuzumab and crizotinib, symptoms including persistent cough, and chest distress were alleviated significantly. Simultaneously, chest computer tomography showed significant dissipation of lymphangitis carcinomatosa, as well as apparent reduction of pleural effusion. No adverse reactions including nausea, vomiting, diarrhea, or hypertension was observed during the following 2 months. LESSONS: The present case suggested that combinational therapy with trastuzumab and crizotinib might be effective in metastatic gastric cancer patients harboring Her-2 and c-MET amplification, even with a poor PS. It was also implied that gene sequencing might be valuable, especially in patients with limited treatment strategies.


Assuntos
Adenocarcinoma/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Gástricas/tratamento farmacológico , Adenocarcinoma/metabolismo , Adenocarcinoma/secundário , Protocolos de Quimioterapia Combinada Antineoplásica , Crizotinibe/administração & dosagem , Crizotinibe/uso terapêutico , Feminino , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundário , Pessoa de Meia-Idade , Metástase Neoplásica , Proteínas Proto-Oncogênicas c-met/metabolismo , Receptor ErbB-2/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Trastuzumab/administração & dosagem , Trastuzumab/uso terapêutico
2.
Nat Commun ; 12(1): 5066, 2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-34417456

RESUMO

Prostate cancer (PCa) shows strong dependence on the androgen receptor (AR) pathway. Here, we show that squalene epoxidase (SQLE), an enzyme of the cholesterol biosynthesis pathway, is overexpressed in advanced PCa and its expression correlates with poor survival. SQLE expression is controlled by micro-RNA 205 (miR-205), which is significantly downregulated in advanced PCa. Restoration of miR-205 expression or competitive inhibition of SQLE led to inhibition of de novo cholesterol biosynthesis. Furthermore, SQLE was essential for proliferation of AR-positive PCa cell lines, including abiraterone or enzalutamide resistant derivatives, and blocked transactivation of the AR pathway. Inhibition of SQLE with the FDA approved antifungal drug terbinafine also efficiently blocked orthotopic tumour growth in mice. Finally, terbinafine reduced levels of prostate specific antigen (PSA) in three out of four late-stage PCa patients. These results highlight SQLE as a therapeutic target for the treatment of advanced PCa.


Assuntos
Colesterol/biossíntese , Regulação para Baixo/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Esqualeno Mono-Oxigenase/antagonistas & inibidores , Idoso , Idoso de 80 Anos ou mais , Animais , Sequência de Bases , Linhagem Celular Tumoral , Proliferação de Células/genética , Sobrevivência Celular , Estudos de Coortes , Simulação por Computador , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Masculino , Camundongos , Camundongos SCID , MicroRNAs/genética , Pessoa de Meia-Idade , Invasividade Neoplásica , Metástase Neoplásica , Estadiamento de Neoplasias , Antígeno Prostático Específico/metabolismo , Neoplasias da Próstata/patologia , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/patologia , Receptores Androgênicos/metabolismo , Esqualeno Mono-Oxigenase/genética , Esqualeno Mono-Oxigenase/metabolismo , Terbinafina/farmacologia , Ativação Transcricional/genética
3.
Nat Commun ; 12(1): 4960, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-34400618

RESUMO

Agonists of glucocorticoid receptor (GR) are frequently given to cancer patients with platinum-containing chemotherapy to reduce inflammation, but how GR influences tumor growth in response to platinum-based chemotherapy such as cisplatin through inflammation-independent signaling remains largely unclear. Combined genomics and transcription factor profiling reveal that MAST1, a critical platinum resistance factor that reprograms the MAPK pathway, is upregulated upon cisplatin exposure through activated transcription factor GR. Mechanistically, cisplatin binds to C622 in GR and recruits GR to the nucleus for its activation, which induces MAST1 expression and consequently reactivates MEK signaling. GR nuclear translocation and MAST1 upregulation coordinately occur in patient tumors collected after platinum treatment, and align with patient treatment resistance. Co-treatment with dexamethasone and cisplatin restores cisplatin-resistant tumor growth, whereas addition of the MAST1 inhibitor lestaurtinib abrogates tumor growth while preserving the inhibitory effect of dexamethasone on inflammation in vivo. These findings not only provide insights into the underlying mechanism of GR in cisplatin resistance but also offer an effective alternative therapeutic strategy to improve the clinical outcome of patients receiving platinum-based chemotherapy with GR agonists.


Assuntos
Cisplatino/farmacologia , Proteínas Associadas aos Microtúbulos/metabolismo , Platina/farmacologia , Proteínas Serina-Treonina Quinases/metabolismo , Receptores de Glucocorticoides/efeitos dos fármacos , Receptores de Glucocorticoides/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Núcleo Celular , Sobrevivência Celular , Citocinas , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Associadas aos Microtúbulos/genética , Receptores de Glucocorticoides/genética , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição , Regulação para Cima/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Free Radic Biol Med ; 174: 202-210, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34364982

RESUMO

The intrinsic chemoresistance of pancreatic ductal adenocarcinoma (PDAC) represents the main obstacle in treating this aggressive malignancy. It has been observed that high antioxidant levels and upregulated Nrf2 and the YAP protein expression can be involved in PDAC chemoresistance. The mechanisms of Nrf2 and YAP increase need to be clarified. We chose a panel of PDAC cell lines with diverse sensitivity to cisplatin and gemcitabine. In PANC-1 chemoresistant cells, we found a low level of oxidative stress and high levels of Nrf2 and YAP protein expressions and their respective targets. On the contrary, in CFPAC-1 chemosensitive cells, we found high levels of oxidative stress and low level of these two proteins, as well as their respective targets. In MiaPaCa-2 cells with a middle chemoresistance, we observed intermediate features. When Nrf2 and YAP were inhibited in PANC-1 cells by Ailanthone, a plant extract, we observed a reduction of viability, thus sustaining the role of these two proteins in maintaining the PDAC chemoresistance. We then delved into the mechanisms of the Nrf2 and YAP protein upregulation in chemoresistance, discovering that it was at a post-translational level since the mRNA expressions did not match the protein levels. Treatments of PANC-1 cells with the proteasome inhibitor MG-132 and the protein synthesis inhibitor cycloheximide further confirmed this observation. The expression of DUB3 and OTUD1 deubiquitinases, involved in the control of Nrf2 and YAP protein level, respectively, was also investigated. Both protein expressions were higher in PANC-1 cells, intermediate in MiaPaCa-2 cells, and lower in CFPAC-1 cells. When DUB3 or OTUD1 were silenced, both Nrf2 and YAP expressions were downregulated. Importantly, in deubiquitinase-silenced cells, we observed a great reduction of proliferation and a higher sensitivity to gemcitabine treatment, suggesting that DUB3 and OTUD1 can represent a suitable target to overcome chemoresistance in PDAC cells.


Assuntos
Fator 2 Relacionado a NF-E2 , Neoplasias Pancreáticas , Linhagem Celular Tumoral , Enzimas Desubiquitinantes , Regulação para Baixo , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Proteases Específicas de Ubiquitina
5.
Medicine (Baltimore) ; 100(34): e27011, 2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34449472

RESUMO

RATIONALE: Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract. Common sites for metastasis are the liver and peritoneum, whereas skeletal muscle metastases are rare. PATIENT CONCERNS: A 59-year-old man with skeletal muscle metastasis was diagnosed during a period of adjuvant imatinib therapy following the recurrence of GIST of the small intestine. DIAGNOSIS: The patient was diagnosed with skeletal muscle metastasis of GIST based on immunohistochemistry and molecular pathology analysis results. INTERVENTION: Extensive resection of the left thigh tumor was performed. The patient underwent whole-exome sequencing of tissue examination. The results suggest that resistance to imatinib may have been developed, and the patient was therefore administered sunitinib instead. OUTCOMES: Complete remission was observed following sunitinib therapy. LESSONS: In cases of skeletal muscle metastasis diagnosed during a period of adjuvant imatinib therapy following the recurrence of a GIST of the small intestine, whole exome sequencing may be used to discover more gene variations.


Assuntos
Neoplasias Gastrointestinais/patologia , Tumores do Estroma Gastrointestinal/patologia , Neoplasias Musculares/secundário , Músculo Esquelético/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Gastrointestinais/tratamento farmacológico , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Humanos , Mesilato de Imatinib/uso terapêutico , Masculino , Pessoa de Meia-Idade , Neoplasias Musculares/tratamento farmacológico , Neoplasias Musculares/cirurgia , Sunitinibe/uso terapêutico , Coxa da Perna/patologia , Sequenciamento Completo do Exoma
6.
In Vivo ; 35(5): 2661-2667, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34410954

RESUMO

BACKGROUND/AIM: Chronic Myeloid Leukemia (CML) is a clonal myeloproliferative disease, and a major challenge for the eradication of CML is to understand the cause of the permanence of minimal residual disease (DRM). This work aimed to induce the maturation of leukemic stem cells with All-trans-retinoic acid (ATRA), making them sensitive to treatment with Imatinib (IM). MATERIALS AND METHODS: K562 cells were treated with IM and with the combined therapy of ATRA together with IM for 48 and 72 h. The expression of BCR-ABL gene and multidrug resistance gene ABCB1 were evaluated using RT-qPCR. RESULTS: The combined ATRA and IM therapy showed a discreet cell differentiation pattern, evidenced by the panoptic morphology analysis at 48 and 72 h of treatment. The BCR-ABL expression showed no statistical difference when treated alone with IM, however in combination with ATRA, the expression was statistically significant in 48 and 72 h (p≤0.0001) and when the treatment groups were compared to each other (p≤0.001). The ABCB1 gene expression showed a decrease in isolated IM therapy (p≤0.05) and in the combination in 48 and 72 h (p≤0.0001). CONCLUSION: Combined ATRA and IM therapy was shown to be effective in decreasing BCR-ABL and ABCB1 genes, possibly through the differentiation of blast cells, demonstrating that the therapy could be potentially effective in the blast crisis of the disease and for those patients who develop resistance to available CML treatments.


Assuntos
Benzamidas , Leucemia Mielogênica Crônica BCR-ABL Positiva , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Apoptose , Diferenciação Celular , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas de Fusão bcr-abl/genética , Humanos , Mesilato de Imatinib/farmacologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Piperazinas , Pirimidinas/farmacologia , Tretinoína
7.
In Vivo ; 35(5): 2941-2945, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34410991

RESUMO

BACKGROUND: Osimertinib is a third-generation EGFR-tyrosine kinase inhibitor approved for the treatment of T790M-positive non-small-cell lung cancer. More recently, osimertinib demonstrated improved disease control compared to other EGFR-TKIs. Multiple mechanisms of resistance have been described in T790M-positive patients who experienced treatment failure with osimertinib. CASE REPORT: We report the case of a 78-year-old non-smoker woman with stage IV EGFR L858R-positive lung adenocarcinoma presented with T790M mutation after five years of treatment with gefitinib. The patient was started on osimertinib, but after two and a half years of treatment experienced disease progression. The analyses of circulating tumor DNA using next-generation sequencing showed, together with the pre-existing T790M and exon 21 L858R, the presence of the EGFR C797G resistance mutation. CONCLUSION: Our case report revealed a rare EGFR-dependent acquired resistance mutation to osimertinib in circulating tumor DNA. Liquid biopsy appears to be a promising resource to understand the biology of osimertinib resistance by clonal evolution monitoring and the identification of novel resistance mechanisms.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Acrilamidas , Idoso , Compostos de Anilina , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/genética , Feminino , Humanos , Biópsia Líquida , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação , Inibidores de Proteínas Quinases/uso terapêutico
8.
Int J Mol Sci ; 22(16)2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34445264

RESUMO

The multidrug efflux transporter ABCB1 is clinically important for drug absorption and distribution and can be a determinant of chemotherapy failure. Recent structure data shows that three glutamines donate hydrogen bonds to coordinate taxol in the drug binding pocket. This is consistent with earlier drug structure-activity relationships that implicated the importance of hydrogen bonds in drug recognition by ABCB1. By replacing the glutamines with alanines we have tested whether any, or all, of Gln347, Gln725, and Gln990 are important for the transport of three different drug classes. Flow cytometric transport assays show that Q347A and Q990A act synergistically to reduce transport of Calcein-AM, BODIPY-verapamil, and OREGON GREEN-taxol bisacetate but the magnitude of the effect was dependent on the test drug and no combination of mutations completely abrogated function. Surprisingly, Q725A mutants generally improved transport of Calcein-AM and BODIPY-verapamil, suggesting that engagement of the wild-type Gln725 in a hydrogen bond is inhibitory for the transport mechanism. To test transport of unmodified taxol, stable expression of Q347/725A and the triple mutant was engineered and shown to confer equivalent resistance to the drug as the wild-type transporter, further indicating that none of these potential hydrogen bonds between transporter and transport substrate are critical for the function of ABCB1. The implications of the data for plasticity of the drug binding pocket are discussed.


Assuntos
Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Paclitaxel/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Substituição de Aminoácidos , Resistencia a Medicamentos Antineoplásicos/genética , Glutamina/genética , Glutamina/metabolismo , Células HEK293 , Humanos , Mutação de Sentido Incorreto
9.
Molecules ; 26(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34361789

RESUMO

Isobavachalcone (IBC) is an active substance from the medicinal plant Psoralea corylifolia. This prenylated chalcone was reported to possess antioxidative, anti-inflammatory, antibacterial, and anticancer activities. Multidrug resistance (MDR) associated with the over-expression of the transporters of vast substrate specificity such as ABCB1 (P-glycoprotein) belongs to the main causes of cancer chemotherapy failure. The cytotoxic, MDR reversing, and ABCB1-inhibiting potency of isobavachalcone was studied in two cellular models: human colorectal adenocarcinoma HT29 cell line and its resistant counterpart HT29/Dx in which doxorubicin resistance was induced by prolonged drug treatment, and the variant of MDCK cells transfected with the human gene encoding ABCB1. Because MDR modulators are frequently membrane-active substances, the interaction of isobavachalcone with model phosphatidylcholine bilayers was studied by means of differential scanning calorimetry. Molecular modeling was employed to characterize the process of membrane permeation by isobavachalcone. IBC interacted with ABCB1 transporter, being a substrate and/or competitive inhibitor of ABCB1. Moreover, IBC intercalated into model membranes, significantly affecting the parameters of their main phospholipid phase transition. It was concluded that isobavachalcone interfered both with the lipid phase of cellular membrane and with ABCB1 transporter, and for this reason, its activity in MDR cancer cells was presumptively beneficial.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Chalconas/farmacologia , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Psoralea/química , Subfamília B de Transportador de Cassetes de Ligação de ATP/antagonistas & inibidores , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Animais , Antibióticos Antineoplásicos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Ligação Competitiva , Linhagem Celular Tumoral , Chalconas/química , Chalconas/isolamento & purificação , Cães , Combinação de Medicamentos , Resistencia a Medicamentos Antineoplásicos/genética , Expressão Gênica , Células HT29 , Humanos , Concentração Inibidora 50 , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , Células Madin Darby de Rim Canino , Membranas Artificiais , Modelos Moleculares , Fosfatidilcolinas/química , Fosfatidilcolinas/metabolismo , Extratos Vegetais/química , Plantas Medicinais , Ligação Proteica , Transgenes , Verapamil/farmacologia
10.
Int J Mol Sci ; 22(15)2021 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-34361090

RESUMO

Glioblastoma (GBM) is a highly lethal cancer that is universally refractory to the standard multimodal therapies of surgical resection, radiation, and chemotherapy treatment. Temozolomide (TMZ) is currently the best chemotherapy agent for GBM, but the durability of response is epigenetically dependent and often short-lived secondary to tumor resistance. Therapies that can provide synergy to chemoradiation are desperately needed in GBM. There is accumulating evidence that adaptive resistance evolution in GBM is facilitated through treatment-induced epigenetic modifications. Epigenetic alterations of DNA methylation, histone modifications, and chromatin remodeling have all been implicated as mechanisms that enhance accessibility for transcriptional activation of genes that play critical roles in GBM resistance and lethality. Hence, understanding and targeting epigenetic modifications associated with GBM resistance is of utmost priority. In this review, we summarize the latest updates on the impact of epigenetic modifications on adaptive resistance evolution in GBM to therapy.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Metilação de DNA , Resistencia a Medicamentos Antineoplásicos/genética , Epigênese Genética , Glioblastoma/tratamento farmacológico , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Evolução Molecular , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Glioblastoma/patologia , Humanos
11.
Cancer Sci ; 112(9): 3585-3597, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34252986

RESUMO

Diffuse large B cell lymphoma (DLBCL) heterogeneity promotes recurrence and anti-CD20-based therapeutic resistance. Previous studies have shown that downregulation of MS4A1/CD20 expression after chemoimmunotherapy with rituximab leads to rituximab resistance. However, the mechanisms of CD20 loss remain unknown. We identified that pyruvate dehydrogenase kinase 4 (PDK4) is markedly elevated in DLBCL cells derived from both patients and cell lines with R-CHOP (rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone) resistance. We found that overexpression of PDK4 in DLBCL cells resulted in cell proliferation and resistance to rituximab in vitro and in vivo. Furthermore, loss of PDK4 expression or treatment with the PDK4 inhibitor dichloroacetate was able to significantly increase rituximab-induced cell apoptosis in DLBCL cells. Further studies suggested PDK4 mediates a metabolic shift, in that the main energy source was changed from oxidative phosphorylation to glycolysis, and the metabolic changes could play an important role in rituximab resistance. Importantly, by knocking down or overexpressing PDK4 in DLBCL cells, we showed that PDK4 has a negative regulation effect on MS4A1/CD20 expression. Collectively, this is the first study showing that targeting PDK4 has the potential to overcome rituximab resistance in DLBCL.


Assuntos
Antígenos CD20/metabolismo , Antineoplásicos Imunológicos/administração & dosagem , Reprogramação Celular/genética , Resistencia a Medicamentos Antineoplásicos/genética , Glicoproteínas/metabolismo , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/metabolismo , Piruvato Desidrogenase Quinase de Transferência de Acetil/metabolismo , Rituximab/administração & dosagem , Transdução de Sinais/genética , Adolescente , Adulto , Idoso , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Humanos , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Piruvato Desidrogenase Quinase de Transferência de Acetil/genética , Transfecção , Resultado do Tratamento , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/genética , Ensaios Antitumorais Modelo de Xenoenxerto , Adulto Jovem
12.
Nat Commun ; 12(1): 4172, 2021 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-34234141

RESUMO

Cell-free DNA (cfDNA) is attractive for many applications, including detecting cancer, identifying the tissue of origin, and monitoring. A fundamental task underlying these applications is SNV calling from cfDNA, which is hindered by the very low tumor content. Thus sensitive and accurate detection of low-frequency mutations (<5%) remains challenging for existing SNV callers. Here we present cfSNV, a method incorporating multi-layer error suppression and hierarchical mutation calling, to address this challenge. Furthermore, by leveraging cfDNA's comprehensive coverage of tumor clonal landscape, cfSNV can profile mutations in subclones. In both simulated and real patient data, cfSNV outperforms existing tools in sensitivity while maintaining high precision. cfSNV enhances the clinical utilities of cfDNA by improving mutation detection performance in medium-depth sequencing data, therefore making Whole-Exome Sequencing a viable option. As an example, we demonstrate that the tumor mutation profile from cfDNA WES data can provide an effective biomarker to predict immunotherapy outcomes.


Assuntos
DNA Tumoral Circulante/genética , Análise Mutacional de DNA/métodos , Inibidores de Checkpoint Imunológico/farmacologia , Neoplasias/genética , Sequenciamento Completo do Exoma/métodos , Adulto , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Biópsia , DNA Tumoral Circulante/sangue , Simulação por Computador , Conjuntos de Dados como Assunto , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Masculino , Pessoa de Meia-Idade , Mutação , Neoplasias/sangue , Neoplasias/tratamento farmacológico , Neoplasias/mortalidade , Polimorfismo de Nucleotídeo Único , Prognóstico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Intervalo Livre de Progressão , Sensibilidade e Especificidade
13.
Gene ; 799: 145808, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34224831

RESUMO

We set out to uncover transcriptome and chromatin landscape changes that occur in HER2 + breast cancer (BC) cells upon acquiring resistance to trastuzumab. RNA-seq analysis was applied to two independently-derived BC cell lines with acquired resistance to trastuzumab (SKBr3.HerR and BT-474HerR) and their parental drug-sensitive cell lines (SKBr3 and BT-474). Chromatin landscape analysis indicated that the most significant increase in accessibility in resistant cells occurs in PPP1R1B within a segment spanning introns 1b through intron 3. Footprint analysis of this segment revealed that FoxJ3 (within intron 2) and Pou5A1/Sox2 (within inton 3) transcription factor motifs are protected in resistant cells. Overall, 344 shared genes were upregulated in both resistant cell lines relative to their parental counterparts and 453 shared genes were downregulated in both resistant cell lines relative to their parental counterparts. In resistant cells, genes associated with autophagy and mitochondria organization are upregulated and genes associated with ribosome assembly and cell cycle are downregulated relative to parental cells. The five top upregulated genes in drug-resistant breast cancer cells are APOD, AZGP1, ETV5, ALPP, and PPP1R1B. This is the first report of increased chromatin accessibility within PPP1R1B associated with its t-Darpp transcript increase, and points to a possible mechanism for its activation in trastuzumab-resistant cells.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Cromatina/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Trastuzumab/farmacologia , Antineoplásicos Imunológicos/farmacologia , Autofagia/efeitos dos fármacos , Autofagia/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Cromatina/genética , Fosfoproteína 32 Regulada por cAMP e Dopamina/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Fatores de Transcrição Forkhead/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Redes Reguladoras de Genes , Humanos , Receptor ErbB-2/metabolismo , Fatores de Transcrição SOXB1/genética
15.
Adv Clin Exp Med ; 30(8): 849-857, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34286518

RESUMO

BACKGROUND: Induction of acquired drug resistance occurs frequently with cisplatin-based therapy for non-small cell lung cancer (NSCLC). As recent studies have demonstrated that deregulation of microRNAs (miRNAs) is associated with drug resistance in cancers, correcting the deregulation of miRNAs represents a promising strategy to reverse acquired resistance in NSCLC. OBJECTIVES: This study investigated the functional role of miR-15b in cisplatin resistance in NSCLC. MATERIAL AND METHODS: Cisplatin-resistant PC9 and A549 NSCLC cell lines (PC9-R and A549-R) were established through long-term exposure to cisplatin. Differences in miR-15b expression between cisplatin-resistant NSCLC cell lines and their parental cell lines were identified through quantitative real-time polymerase chain reaction (qRT-PCR). The effect of anti-miR-15b on the sensitivity of PC9-R and A549-R to cisplatin-induced cytotoxicity was evaluated using Cell Counting Kit-8 (CCK-8) assays. Regulation of GSK-3ß by miR-15b was confirmed with luciferase reporter assays. Cell apoptosis and mitochondrial membrane potential (MMP) were measured using flow cytometry analysis. RESULTS: In PC9-R and A549-R cells, miR-15b was significantly overexpressed. However, knockdown of miR-15b clearly reduced cisplatin resistance in PC9-R and A549-R cells. Researching the mechanism, we proved that GSK-3ß was the target of miR-15b. Knockdown of miR-15b significantly increased the expression GSK-3ß and thus promoted the degradation of MCL-1, which is a key anti-apoptosis protein. As a result, anti-miR-15b expanded the cisplatin-induced apoptosis in cisplatin-resistant NSCLC cells. CONCLUSIONS: Knockdown of miR-15b partially reversed cisplatin resistance in NSCLC cells through the GSK-3ß/MCL-1 pathway.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , MicroRNAs , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Quinase 3 da Glicogênio Sintase/farmacologia , Quinase 3 da Glicogênio Sintase/uso terapêutico , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , MicroRNAs/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/uso terapêutico
16.
Cell Death Dis ; 12(7): 696, 2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34257270

RESUMO

Trastuzumab resistance negatively influences the clinical efficacy of the therapy for human epidermal growth factor receptor 2 (HER2) positive gastric cancer (GC), and the underlying mechanisms remain elusive. Exploring the mechanisms and finding effective approaches to address trastuzumab resistance are of great necessity. Here, we confirmed that endoplasmic reticulum (ER) stress-induced trastuzumab resistance by up-regulating miR-301a-3p in HER2-positive GC cells. Moreover, we elucidated that miR-301a-3p mediated trastuzumab resistance by down-regulating the expression of leucine-rich repeats and immunoglobulin-like domains containing protein 1 (LRIG1) and subsequently activating the expression of insulin-like growth factor 1 receptor (IGF-1R) and fibroblast growth factor receptor 1 (FGFR1) under ER stress. We also found that intercellular transfer of miR-301a-3p by exosomes disseminated trastuzumab resistance. The present study demonstrated that exosomal miR-301a-3p could serve as a non-invasive biomarker for trastuzumab resistance, which was maybe a novel potential therapeutic target to overcome trastuzumab resistance and improve the curative effect of trastuzumab in HER2-positive GC patients.


Assuntos
Antineoplásicos Imunológicos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , MicroRNAs/metabolismo , Receptor ErbB-2/antagonistas & inibidores , Neoplasias Gástricas/tratamento farmacológico , Trastuzumab/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , Receptor ErbB-2/metabolismo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo , Transdução de Sinais , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Cell Death Dis ; 12(7): 702, 2021 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-34262023

RESUMO

Acquired resistance to glucocorticoids (GCs) is an obstacle to the effective treatment of leukemia, but the molecular mechanisms of steroid insensitivity have not been fully elucidated. In this study, we established an acquired GC-resistant leukemia cell model and found a long noncoding RNA, HOTAIRM1, was overexpressed in the resistant cells by transcriptional profiling, and was higher expressed in patients with poor prognosis. The whole-genome-binding sites of HOTAIRM1 were determined by ChIRP-seq (chromatin isolation by RNA purification combined with sequencing) analysis. Further study determined that HOTAIRM1 bound to the transcriptional inhibitory region of ARHGAP18 and repressed the expression of ARHGAP18, which led to the increase of RHOA/ROCK1 signaling pathway and promoted GC resistance through antiapoptosis of leukemia cells. The inhibition of ROCK1 in GC-resistant cells could restore GCs responsiveness. In addition, HOTAIRM1 could also act as a protein sequester to prevent transcription factor AML1(acute myeloid leukemia 1) from binding to the regulatory region of ARHGAP18 by interacting with AML1. At last, we also proved AML1 could directly activate the expression of HOTAIRM1 through binding to the promoter of HOTAIRM1, which enriched the knowledge on the regulation of lncRNAs. This study revealed epigenetic causes of glucocorticoid resistance from the perspective of lncRNA, and laid a foundation for the optimization of glucocorticoid-based leukemia treatment strategy in clinic.


Assuntos
Antineoplásicos/farmacologia , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Dexametasona/farmacologia , Resistencia a Medicamentos Antineoplásicos , Proteínas Ativadoras de GTPase/metabolismo , Glucocorticoides/farmacologia , Leucemia/tratamento farmacológico , MicroRNAs/metabolismo , Quinases Associadas a rho/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo , Apoptose/efeitos dos fármacos , Sítios de Ligação , Linhagem Celular Tumoral , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas Ativadoras de GTPase/genética , Regulação Leucêmica da Expressão Gênica , Células HEK293 , Humanos , Leucemia/enzimologia , Leucemia/genética , Leucemia/patologia , MicroRNAs/genética , Ligação Proteica , Transdução de Sinais , Quinases Associadas a rho/genética , Proteína rhoA de Ligação ao GTP/genética
18.
Mol Med Rep ; 24(4)2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34328193

RESUMO

Lung cancer is one of the most prevalent cancers in China, and its incidence and morbidity remain high due to various independent factors. Lung adenocarcinoma (ADC) is the most common type of non­small cell lung carcinoma. Circular RNA plasmacytoma variant translocation 1 (circ­PVT1) plays an oncogenic role in various types of cancer, but the specific role of circ­PVT1 in lung ADC has not yet been reported. In the present study, circ­PVT1 was knocked down in A549 cells and the cell viability, proliferation, migration and invasion were measured via MTT, colony formation, wound healing and Transwell assays, respectively. Then, the cell viability of A549 cells with circ­PVT1­knockdown or ­overexpression was detected after exposure to cisplatin (DDP). After confirming the associations among circ­PVT1, microRNA (miR)­429 and forkhead box k1 (FOXK1) using various tools and assays, the cellular functions of A549 cells treated with combined short hairpin (sh)RNA­circ­PVT1 and miR­429 inhibitor/pcDNA3.1­FOXK1 were tested again. The expression of circ­PVT1 was found to be increased in lung ADC cells, and shRNA­circ­PVT1 led to decreased cell viability, proliferation, migration and invasion. The expression of circ­PVT1 was higher in A549/DDP cells than that in A549 cells, and the activity of caspase­3 was also activated by DDP in A549/DDP cells transfected with shRNA­circ­PVT1, whereas it was inactivated by DDP in A549 cells transfected with circ­PVT1 overexpression plasmid. Furthermore, the decreased cell viability, proliferation, invasion and migration induced by shRNA­circ­PVT1 could be abated by transfection with miR­429 inhibitor and pcDNA3.1­FOXK1. In conclusion, interference of circ­PVT1 inhibits the progression of lung ADC and enhances its sensitivity to DDP via miR­429/FOXK1, which may provide a theoretical basis for the use of novel targets in the treatment of lung ADC.


Assuntos
Adenocarcinoma de Pulmão/genética , Fatores de Transcrição Forkhead/metabolismo , Neoplasias Pulmonares/genética , MicroRNAs/metabolismo , RNA Circular/genética , RNA Circular/metabolismo , Células A549 , Adenocarcinoma de Pulmão/tratamento farmacológico , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Movimento Celular/genética , Proliferação de Células/genética , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Fatores de Transcrição Forkhead/genética , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Pulmonares/tratamento farmacológico , MicroRNAs/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
19.
Lung Cancer ; 159: 42-44, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34304052

RESUMO

EGFR-mutant adenocarcinomas represent 12% of unselected lung adenocarcinomas and 44% of never smoker adenocarcinomas in the Caucasian population. Activating mutations like exon19 deletion or exon21 Leu858Arg point mutations are predictive of tumor response to EGFR tyrosine kinase inhibitors. Unfortunately, acquired resistance inevitably occurs by the development of novel EGFR mutations, mutations in other genes, gene amplification, gene fusion or tumor transformation. The management of tumors presenting multiple targetable mutations is unclear. We present the case of a patient developing a BRAFV600 mutation as acquired resistance mechanism to osimertinib, who responded favorably to the combination of dabrafenib, trametinib and osimertinib.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/genética , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/genética , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Quinases de Proteína Quinase Ativadas por Mitógeno , Mutação , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/genética
20.
Mol Cell ; 81(15): 3128-3144.e7, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34216544

RESUMO

Mutations in BRCA1 or BRCA2 (BRCA) is synthetic lethal with poly(ADP-ribose) polymerase inhibitors (PARPi). Lethality is thought to derive from DNA double-stranded breaks (DSBs) necessitating BRCA function in homologous recombination (HR) and/or fork protection (FP). Here, we report instead that toxicity derives from replication gaps. BRCA1- or FANCJ-deficient cells, with common repair defects but distinct PARPi responses, reveal gaps as a distinguishing factor. We further uncouple HR, FP, and fork speed from PARPi response. Instead, gaps characterize BRCA-deficient cells, are diminished upon resistance, restored upon resensitization, and, when exposed, augment PARPi toxicity. Unchallenged BRCA1-deficient cells have elevated poly(ADP-ribose) and chromatin-associated PARP1, but aberrantly low XRCC1 consistent with defects in backup Okazaki fragment processing (OFP). 53BP1 loss resuscitates OFP by restoring XRCC1-LIG3 that suppresses the sensitivity of BRCA1-deficient cells to drugs targeting OFP or generating gaps. We highlight gaps as a determinant of PARPi toxicity changing the paradigm for synthetic lethal interactions.


Assuntos
Proteína BRCA1/genética , Replicação do DNA/efeitos dos fármacos , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Animais , Linhagem Celular , Cisplatino/farmacologia , DNA/genética , DNA/metabolismo , DNA de Cadeia Simples/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas de Grupos de Complementação da Anemia de Fanconi/genética , Recombinação Homóloga/efeitos dos fármacos , Humanos , Camundongos Endogâmicos NOD , RNA Helicases/genética , Rad51 Recombinase/genética , Proteína de Replicação A/genética , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...