miR-146a inhibits cell growth, cell migration and induces apoptosis in non-small cell lung cancer cells.

Aberrant expression of microRNA-146a (miR-146a) has been reported to be involved in the development and progression of various types of cancers. However, its role in non-small cell lung cancer (NSCLC) has not been elucidated. The aim of this study was to investigate the contribution of miR-146a to various aspects of the malignant phenotype of human NSCLCs. In functional experiments, miR-146a suppressed cell growth, induced cellular apoptosis and inhibited EGFR downstream signaling in five NSCLC cell lines (H358, H1650, H1975, HCC827 and H292). miR-146a also inhibited the migratory capacity of these NSCLC cells. On the other hand, miR-146a enhanced the inhibition of cell proliferation by drugs targeting EGFR, including both TKIs (gefitinib, erlotinib, and afatinib) and a monoclonal antibody (cetuximab). These effects were independent of the EGFR mutation status (wild type, sensitizing mutation or resistance mutation), but were less potent compared to the effects of siRNA targeting of EGFR. Our results suggest that these effects of miR-146a are due to its targeting of EGFR and NF-kappaB signaling. We also found, in clinical formalin fixed paraffin embedded (FFPE) lung cancer samples, that low expression of miR-146a was correlated with advanced clinical TNM stages and distant metastasis in NSCLC (P<0.05). The patients with high miR-146a expression in their tumors showed longer progression-free survival (25.6 weeks in miR-146a high patients vs. 4.8 weeks in miR-146a low patients, P<0.05). miR-146a is therefore a strong candidate prognostic biomarker in NSCLC. Thus inducing miR-146a might be a therapeutic strategy for NSCLC

A multicenter cohort study of dose-dense temozolomide (21 of 28 days) for the treatment of recurrent anaplastic astrocytoma or oligoastrocytoma.

Dose-dense temozolomide schedules deplete O6-methylguanine methyltransferase and may overcome chemoresistance. This multicenter cohort study enrolled 19 patients (15 anaplastic astrocytoma, 4 anaplastic oligoastrocytoma) who received temozolomide (100 mg/m2/day for 21 consecutive days every 28-day cycle) at first recurrence, either until disease progression or 12 cycles. Six-month progression-free survival was 56%, comparing favorably with historic controls treated with the standard 5-day temozolomide schedule. Median survival was 12.9 months (95% CI: 3.7, 22 months). Among 15 evaluable patients, 2 had a complete or partial response, and 10 had stable disease. Grade 3 and 4 lymphopenia occurred in 53% and 47% of patients, respectively

Correlation of EGFR, IDH1 and PTEN status with the outcome of patients with recurrent glioblastoma treated in a phase II clinical trial with the EGFR-blocking monoclonal antibody cetuximab

Mutation and gene amplification of the epithelial growth factor receptor (EGFR) is one of the most common genetic alterations in glioblastoma (GB). EGFR is, therefore, an attractive molecular target for the treatment of GB. EGFR-targeted therapies however have been largely ineffective in clinical trials. In this study, we investigated the correlation between the EGFR gene amplification status, expression of the EGFR variant III (EGFRvIII) and EGFR variant IV (EGFRvIV) mutations, expression of the phosphatase and tensin homologue gene on chromosome 10 (PTEN) and mutation of the isocitrate dehydrogenase 1 (IDH1) gene and the survival of patients suffering from recurrent glioblastoma who were treated with the EGFR-targeted monoclonal antibody cetuximab in a prospective phase II clinical trial. EGFR amplification was detected in 19 out of 35 GB (54%), EGFRvIII expression in 11 (31.4%) and EGFRvIV expression in 7 (20%). The EGFRvIII and EGFRvIV mutations were exclusively found in GB with EGFR amplification and were almost mutually exclusive with IDH1 mutation (EGFRvIII mutation was found in 1 out of 11 GB with an IDH1 mutation). Patients with an EGFR amplification lacking EGFRvIII expression had a significantly superior progression free survival (PFS) and a numerical better overall survival (OS) following treatment with cetuximab [median PFS 3.03 vs. 1.63 months (p=0.006); median OS 5.57 vs. 3.97 months (p=0.12)]. Within the subgroup of patients with EGFR amplification, patients with EGFRvIII positive glioblastoma had a worse survival [median PFS 1.63 vs. 3.03 months (p=0.01); median OS 3.27 vs. 5.57 months (p=0.08)]. Our observations indicate that the type of EGFR mutation may determine the outcome of GB patients treated with cetuximab. Prospective investigation of both the EGFR amplification and mutation status in clinical trials with EGFR-targeted therapies for GB is indicated.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Correlation between IDH1 gene mutation status and survival of patients treated for recurrent glioma

Somatic mutations in the isocitrate dehydrogenase 1 (IDH1) gene have been frequently found in low-grade glioma and secondary glioblastoma and are associated with a significantly younger age at diagnosis and a superior overall survival. We investigated the IDH1 gene mutation status by nested PCR and denaturing gradient gel electrophoresis (DGGE) on DNA extracted from archival tumor blocks of 63 glioma patients who were treated following recurrence with the epidermal growth factor receptor (EGFR)-targeted blocking monoclonal antibody cetuximab, or the vascular endothelial growth factor (receptor) (VEGF(R))-targeted agents sunitinib malate and bevacizumab. In our study population, IDH1 mutation was significantly correlated with a longer overall survival (OS) from the time of initial diagnosis. Patients with IDH1 mutation also had a superior OS from the time of recurrence when treated with sunitinib or bevacizumab but a worse OS when treated with cetuximab. Our observations support the hypothesis that IDH1 mutation may correlate with the benefit from VEGF(R)- versus EGFR-targeted therapy at the time of recurrence in glioma patients.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

miR-146a induces apoptosis with hoechst 33342 and PI double fluorescent staining.

<p>The effect of miR-146a on apoptosis in H358, H1650 and H1975 was examined with hoechst 33342 and PI double fluorescent staining. * <i>P</i><0.05, ** <i>P</i><0.01 compared to blank control at the same time point.</p

miR-146a inhibits cell proliferation with MTS in HCC827 and H292 cell lines.

<p>NSCLC cells were treated as mentioned in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0060317#pone-0060317-g001" target="_blank">Figure 1</a>. * <i>P</i><0.05 compared to blank control at the same time point.</p

miR-146a downregulates IRAK-1 in NSCLC cells.

<p>NSCLC cell lines were treated as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0060317#pone-0060317-g004" target="_blank">Figure 4</a>. Antibodies included phospho-IRAK-1 (S³⁷⁶), IRAK-1and β-Actin. C1: Negative control for miRNA inhibitor; C2: Negative control for miRNA mimic; Inhi: miR-146a inhibitor; Mimi: miR-146a mimic; Si: EGFR-specific siRNA.</p

Relationship of miR-146a level and clinicopathological variables in lung cancer tissues.

a<p>FISH negative with no or low genomic gain (≤four copies of gene in >40% of the cells) and FISH positive with gene amplification, defined by the presence of tight gene clusters, a gene/chromosome per cell ratio ≥2, or ≥15 copies of the genes per cell in ≥10% of the analyzed cells or with high polysomy (≥four copies of the gene in ≥40% of the cells). Eight cases had high polysomy and one case had gene amplification. Information for the different variables was not available for all cases in this retrospective series.</p>b<p>Five cases had E746-A750 deletion (exon 19) and one case had L858R point mutation (exon 21).</p