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Although targeted therapy has emerged as an effective treatment strategy for non-small cell lung cancer (NSCLC), some patients cannot benefit from such therapy due to the limited number of therapeutic targets. The present study aimed to identify mutated genes associated with clinicopathological characteristics and prognosis and to screen for mutations that are not concurrent with applicable drug target sites in patients with NSCLC. Tumor tissue and blood samples were obtained from 97 patients with NSCLC. A lung cancer-specific panel of 55 genes was established and analyzed using next-generation sequencing (NGS). The results obtained from the clinical cohort were compared with the NSCLC dataset from The Cancer Genome Atlas (TCGA). Subsequently, 25 driver genes were identified by taking the intersection of the 55 lung-cancer-specific genes with three databases, namely, the Catalog of Somatic Mutations in Cancer database, the Network of Cancer Genes database and Vogelstein''s list. Functional annotation and protein-protein interaction analysis were conducted on these 25 driver genes. The χ2 test and logistic regression were used to evaluate the association between mutations in the 25 driver genes and the clinicopathological characteristics of 97 patients, and phosphatase and tensin homolog (PTEN) and kirsten rat sarcoma viral oncogene homolog (KRAS) were associated with stage at diagnosis and sex, respectively, while epidermal growth factor receptor (EGFR) was associated with sex, stage at diagnosis, metastasis, CEA and CYFRA21-1. Moreover, the association between the 25 driver gene mutations and overall survival were examined using Cox regression analysis. Age and Notch homolog 2 (NOTCH2) mutations were independent prognostic factors in TCGA dataset. The correlations between statistically significant mutations in EGFR, KRAS, PTEN and NOTCH2 were further examined, both in the clinical data and TCGA dataset. There was a negative correlation between EGFR and NOTCH2 mutations (correlation coefficient, −0.078; P=0.027). Thus, the present study highlights the importance of NOTCH2 mutations and might provide novel therapeutic options for patients with NSCLC who do not harbor EGFR mutations.  相似文献   
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MicroRNAs (miRNAs) are involved in the progression of many cancers through largely unelucidated mechanisms. The results of our present study identified a gene cluster, miR-221/222, that is constitutively upregulated in serum exosome samples of patients with colorectal carcinoma (CRC) with liver metastasis (LM); this upregulation predicts a poor overall survival rate. Using an in vitro cell coculture model, we demonstrated that CRC exosomes harboring miR-221/222 activate liver hepatocyte growth factor (HGF) by suppressing SPINT1 expression. Importantly, miR-221/222 plays a key role in forming a favorable premetastatic niche (PMN) that leads to the aggressive nature of CRC, which was further shown through in vivo studies. Overall, our results show that exosomal miR-221/222 promotes CRC progression and may serve as a novel prognostic marker and therapeutic target for CRC with LM.  相似文献   
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??Abstract?? Objective To analyze ALDH3A2 mutation in four Chinese patients with Sjögren-Larsson syndrome ??SLS??. Methods Four patients were clinically diagnosed with SLS. Respectively take 3 ml of peripheral blood. All 11 exons and exon-intron boundaries of ALDH3A2 gene were amplified by polymerase chain reaction ??PCR?? and directly sequenced for genomic DNA. Results 1. All four patients had congenital ichthyosis?? mental retardation??and spastic diplegia or tetraplegia. Patient 1 had a compound heterozygote??c.1157A??G inherited from her father?? IVS5-1del G inherited from her mother. Both her parents had normal phenotype. Patient 2 and Patient 3 were siblings?? they were both homozygotes??a A-to-G transition at nucleotide 1157 in exon 8. The heterozygosity was demonstrated in their mother. Both her parents had normal phenotype. Conclusion Two different mutations were examined in these 4 Chinese patients?? and the SLS cases were confirmed by ALDH3A2 mutation analysis.  相似文献   
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Objective:To compare the esthetic improvements of white-spot lesions (WSLs) treated by fluoride, casein phosphopeptide amorphous calcium phosphate (CPP-ACP), or resin infiltration.Materials and Methods:WSLs were created on human enamel and randomly assigned to four groups: NaF (500 ppm), CPP-ACP, resin infiltration (Icon), or distilled deionized water (DDW; control group). The color change (ΔE) of each specimen was measured with a Crystaleye spectrophotometer, and fluorescence loss (ΔQ) was measured by quantitative light-induced fluorescence (QLF), at different time points after treatment: baseline (0 weeks), 2 weeks, 4 weeks, and 6 weeks.Results:The ΔE and ΔQ baseline values for the four groups before the treatments did not differ significantly. Icon treatment improved the WSL color significantly and gave the lowest ΔE (2.9 ± 1.2 on average) compared with other treatments (P < .01). The Icon treatment also resulted in a significant change in the ΔQ of WSLs compared with baseline (P < .01). In the NaF and CPP-ACP treatment groups, ΔQ showed significant recovery compared with the baseline values only after 4 weeks after treatment (P < .05).Conclusions:Resin infiltration is more effective than NaF or CPP-ACP in providing esthetic improvement of WSLs.  相似文献   
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