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1.
Cancer Gene Ther ; 29(10): 1439-1451, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35388172

RESUMO

Increased vascular permeability facilitates metastasis. Cancer-secreted exosomes are emerging mediators of cancer-host crosstalk. Epstein-Barr virus (EBV), identified as the first human tumor-associated virus, plays a crucial role in metastatic tumors, especially in nasopharyngeal carcinoma (NPC). To date, whether and how exosomes from EBV-infected NPC cells affect vascular permeability remains unclear. Here, we show that exosomes from EBV-positive NPC cells, but not exosomes from EBV-negative NPC cells, destroy endothelial cell tight junction (TJ) proteins, which are natural barriers against metastasis, and promote endothelial-to-mesenchymal transition (EndMT) in endothelial cells. Proteomic analysis revealed that the level of HMGA2 protein was higher in exosomes derived from EBV-positive NPC cells compared with that in exosomes derived from EBV-negative NPC cells. Depletion of HMGA2 in exosomes derived from EBV-positive NPC cells attenuates endothelial cell dysfunction and tumor cell metastasis. In contrast, exosomes from HMGA2 overexpressing EBV-negative NPC cells promoted these processes. Furthermore, we showed that HMGA2 upregulates the expression of Snail, which contributes to TJ proteins reduction and EndMT in endothelial cells. Moreover, the level of HMGA2 in circulating exosomes is significantly higher in NPC patients with metastasis than in those without metastasis and healthy negative controls, and the level of HMGA2 in tumor cells is associated with TJ and EndMT protein expression in endothelial cells. Collectively, our findings suggest exosomal HMGA2 from EBV-positive NPC cells promotes tumor metastasis by targeting multiple endothelial TJ and promoting EndMT, which highlights secreted HMGA2 as a potential therapeutic target and a predictive marker for NPC metastasis.


Assuntos
Infecções por Vírus Epstein-Barr , Neoplasias Nasofaríngeas , Linhagem Celular Tumoral , Células Endoteliais/metabolismo , Infecções por Vírus Epstein-Barr/metabolismo , Infecções por Vírus Epstein-Barr/patologia , Proteína HMGA2/genética , Proteína HMGA2/metabolismo , Herpesvirus Humano 4/metabolismo , Humanos , Carcinoma Nasofaríngeo/metabolismo , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/patologia , Proteômica
2.
Mol Cancer Res ; 20(1): 161-175, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34654722

RESUMO

Lymphatic metastasis is a common clinical symptom in nasopharyngeal carcinoma (NPC), the most common Epstein-Barr virus (EBV)-associated head and neck malignancy. However, the effect of EBV on NPC lymph node (LN) metastasis is still unclear. In this study, we demonstrated that EBV infection is strongly associated with advanced clinical N stage and lymphangiogenesis of NPC. We found that NPC cells infected with EBV promote LN metastasis by inducing cancer-associated lymphangiogenesis, whereas these changes were abolished upon clearance of EBV genomes. Mechanistically, EBV-induced VEGF-C contributed to lymphangiogenesis and LN metastasis, and PHLPP1, a target of miR-BART15, partially contributed to AKT/HIF1a hyperactivity and subsequent VEGF-C transcriptional activation. In addition, administration of anti-VEGF-C antibody or HIF1α inhibitors attenuated the lymphangiogenesis and LN metastasis induced by EBV. Finally, we verified the clinical significance of this prometastatic EBV/VEGF-C axis by determining the expression of PHLPP1, AKT, HIF1a, and VEGF-C in NPC specimens with and without EBV. These results uncover a reasonable mechanism for the EBV-modulated LN metastasis microenvironment in NPC, indicating that EBV is a potential therapeutic target for NPC with lymphatic metastasis. IMPLICATIONS: This research demonstrates that EBV induces lymphangiogenesis in NPC by regulating PHLPP1/p-AKT/HIF1a/VEGF-C, providing a new therapeutic target for NPC with lymphatic metastasis.


Assuntos
Infecções por Vírus Epstein-Barr/complicações , Linfangiogênese/genética , Metástase Linfática/fisiopatologia , Carcinoma Nasofaríngeo/fisiopatologia , Fator C de Crescimento do Endotélio Vascular/metabolismo , Animais , Linhagem Celular Tumoral , Humanos , Camundongos , Camundongos Nus , Microambiente Tumoral , Regulação para Cima
3.
Ann Palliat Med ; 10(5): 5897-5901, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33977730

RESUMO

Leptomeningeal metastasis (LM) is a rare but lethal complication of advanced non-small cell lung cancer (NSCLC) that has a devastating impact on patient survival and quality of life. Osimertinib, an irreversible tyrosine kinase inhibitor, is approved as a therapy for advanced NSCLC with epidermal growth factor receptor (EGFR) mutation. However, the efficacy and optimal dosage of osimertinib in the treatment of NSCLC patients with LM who harbor uncommon EGFR mutations have yet to be fully investigated. Herein, we report a case of an advanced NSCLC patient with LM carrying EGFR G719S and L861Q, who was successfully treated by osimertinib at 160 mg. The patient initially presented with clear cell renal carcinoma and renal metastatic adenocarcinoma, and underwent right nephrectomy. At 2 months after nephrectomy, he developed a disturbance of consciousness and was subsequently diagnosed with NSCLC with LM by meningeal biopsy pathology and cerebrospinal fluid (CSF) cytology. Next-generation sequencing detected the rare EGFR mutations G719S and L861R in the meningeal biopsy tissues. The patient was then administered osimertinib at 80 mg quaque die (QD); after 1 month of treatment, his symptoms were alleviated. However, two months later, he experienced epileptic episode. Subsequently, the osimertinib dosage was doubled to 160 mg QD. After 1 month of treatment, the patient achieved central nervous system (CNS) response, and at the time of this manuscript's submission, he had maintained stable disease (SD) for more than 1 year. To our knowledge, this study provides the first clinical evidence that the administration of osimertinib at 160 mg once daily can achieve an encouraging, durable response in an NSCLC patient with LM carrying EGFR G719S and L861Q.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Acrilamidas , Compostos de Anilina , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Receptores ErbB/genética , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Masculino , Mutação , Qualidade de Vida
4.
J Cancer ; 10(14): 3214-3223, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31289592

RESUMO

Background: Nimotuzumab is a humanized anti-epidermal growth factor receptor (EGFR) antibody that has shown preclinical and clinical anticancer activity in cerebral glioblastoma multiforme (GBM). We conducted a phase II, single-arm, multicenter clinical trial to evaluate the benefit of adding nimotuzumab to current standard chemo-radiotherapy for patients with GBM with positive EGFR expression. Methods: Newly diagnosed patients with histologically proven single supratentorial GBM and epidermal growth factor receptor (EGFR) positive expressions were recruited. All patients were treated with nimotuzumab, administered once a week intravenously for 6 weeks in addition to radiotherapy with concomitant and adjuvant temozolomide after surgery. The primary endpoints were overall survival (OS) and progression-free survival (PFS). Secondary objectives included objective response rate (ORR) and toxicity. Results: A total of 39 patients were enrolled and 36 patients were evaluated for efficacy. The ORR at the end of RT was 72.2%. Median OS and PFS were 24.5 and 11.9 months. The 1-year OS and PFS rates were 83.3% and 49.3%. The 2-year OS and PFS rates were 51.1% and 29.0%. O (6)-methylquanine DNA methyl-tranferase (MGMT) expression is known to affect the efficacy of chemotherapy and status of its expression is examined. No significant correlation between treatment outcomes and MGMT status was found. Most frequent treatment-related toxicities were mild to moderate and included constipation, anorexia, fatigue, nausea, vomiting, and leucopenia. Conclusions: Our study show that nimotuzumab in addition to standard treatment is well tolerable and has increased survival in newly diagnosed GBM patients with EGFR positive expression.

5.
Chin J Cancer Res ; 25(2): 206-11, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23592902

RESUMO

OBJECTIVE: We retrospectively studied the efficacy of bevacizumab as salvage therapy for recurrent malignant glioma with a focus on the overall survival (OS). METHODS: Patients who received a therapy other than surgery for recurrent malignant glioma were included. Efficacy was evaluated using MRI. Neurological function was evaluated using the Response Assessment in Neuro-Oncology (RANO). The survival rate was calculated using the Kaplan-Meier method. RESULTS: Fifty-one patients with recurrent glioma (31 grade III, 20 grade IV) were included. Among them, 22 subjects (43.1%) received bevacizumab. The median OS was 10.2 months (range, 1 to 27 months). Patients receiving bevacizumab had comparable OS (a median of 9.9 vs. 10.0 months) and similar 6-month survival rate (43% vs. 34%) to those who did not receive bevacizumab. A subgroup analysis failed to notice any significant difference in grade III glioma patients receiving bevacizumab vs. those who did not. The median survival was significantly longer at 8.9 months (range, 4 to 13 months) in grade IV glioma patients receiving bevacizumab than in those who did not (5.6 months, range, 2 to 7 months, P=0.042). The 6-month survival rate was higher (83%) in those who received bevacizumab than in those who did not (47%, P=0.046). No grade 3/4 adverse events were observed in any patient. CONCLUSIONS: Bevacizumab, as a rescue therapy, provides a survival benefit for recurrent grade IV glioma.

6.
Cancer Epidemiol ; 36(6): 525-7, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22795327

RESUMO

BACKGROUND: Current evidence suggests that a majority of the inherited risks play a major role in glioma susceptibility, and glioma is due to the co-inheritance of multiple low-risk variants. These variants can be identified through association studies including such as genome-wide association studies (GWAS), which has led the glioma epidemiology researchers to focus on identifying potential disease-causing factors. METHODS: We evaluated and validated 10 tag single nucleotide polymorphisms (tSNPs) in seven genes associated with glioma susceptibility in a Han Chinese population, including 301 glioma cases and 302 controls, using a multiplexed single nucleotide polymorphism (SNP) MassEXTEND assay. We ascertained the genotypic frequencies for each tSNP in control subjects were within Hardy-Weinberg equilibrium (HWE) using an exact test, and then compared the genotype and allele frequencies of glioma patients and control subjects using the χ2 test. We then applied three genetic models (dominant, recessive, and additive) using PLINK software to assess the association of each tSNP with glioma risk. RESULTS: We identified two tSNPs to be associated with glioma susceptibility (rs1695, GSTP1, P = 0.019; rs2853676, TERT, P = 0.039), which we confirmed using dominant and additive model analyses. The genotype “GA” for rs1695 was recognized to be a protective genotype for glioma (OR, 0.67; 95% CI, 0.47-0.96; P = 0.027), while the genotype “AG” for rs2853676 was shown to be a risk genotype for glioma (OR, 1.50; 95% CI, 1.05-2.15; P = 0.025). CONCLUSION: Our results, and those from previous studies, suggest potential genetic contributes for GSTP1 and TERT in glioma development.


Assuntos
Neoplasias Encefálicas/genética , Glioma/genética , Glutationa S-Transferase pi/genética , Telomerase/genética , Adulto , Povo Asiático , Neoplasias Encefálicas/enzimologia , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Genótipo , Glioma/enzimologia , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Fatores de Risco
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