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IntroductionMounting evidence supports a role for estrogen signaling in NSCLC progression. We previously reported a seven-gene signature that predicts prognosis in estrogen receptor β positive (ERβ+) NSCLC. The signature defines a network comprised of ER and human EGFR-2/3 (HER2/HER3) signaling.MethodsWe tested the efficacy of combining the pan-HER inhibitor, dacomitinib, with the estrogen antagonist, fulvestrant, in ERβ+ NSCLC models with differing genotypes. We assessed the potency of this combination on xenograft growth and survival of host mice, and the ability to reverse the gene signature associated with poor outcome.ResultsSynergy was observed between dacomitinib and fulvestrant in three human ERβ+ NSCLC models: 201T (wild-type EGFR), A549 (KRAS mutant), and HCC827 (EGFR 19 deletion) with combination indices of 0.1-0.6. The combination, but not single agents, completely reversed the gene signature associated with poor prognosis in a mechanism that is largely mediated by activator protein 1 downregulation. In vivo, the combination also induced tumor regression and reversed the gene signature. In HCC827 xenografts treated with the combination, survival of mice was prolonged after therapy discontinuation, tumors that recurred were less aggressive, and two mechanisms of HER inhibitor resistance involving c-Met activation and PTEN loss were blocked.ConclusionsThe combination of an ER blocker and a pan-HER inhibitor provides synergistic efficacy in different models of ERβ+ NSCLC. Our data support the use of this combination clinically, considering its ability to induce potent antitumor effects and produce a gene signature that predicts better clinical outcomes.  相似文献   
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《Vaccine》2021,39(38):5401-5409
BackgroundPapua New Guinea (PNG) introduced the 13-valent pneumococcal conjugate vaccine (PCV13) in 2014, with administration at 1, 2, and 3 months of age. PCV13 has reduced or eliminated carriage of vaccine types in populations with low pneumococcal carriage prevalence, carriage density and serotype diversity. This study investigated PCV13 impact on serotype-specific pneumococcal carriage prevalence, density, and serotype diversity in PNG infants, who have some of the highest reported rates of pneumococcal carriage and disease in the world.MethodsNasopharyngeal swabs were collected at 1, 4 and 9 months of age from PCV13-vaccinated infants (n = 57) and age-/season-matched, unvaccinated infants (at approximately 1 month, n = 53; 4 months, n = 57; 9 months, n = 52). Serotype-specific pneumococcal carriage density and antimicrobial resistance genes were identified by qPCR and microarray.ResultsPneumococci were present in 89% of swabs, with 60 different serotypes and four non-encapsulated variants detected. Multiple serotype carriage was common (47% of swabs). Vaccine type carriage prevalence was similar between PCV13-vaccinated and unvaccinated infants at 4 and 9 months of age. The prevalence of non-vaccine type carriage was also similar between cohorts, with non-vaccine types present in three-quarters of samples (from both vaccinated and unvaccinated infants) by 4 months of age. The median pneumococcal carriage density was high and similar at each age group (~7.0 log10 genome equivalents/mL). PCV13 had no effect on overall pneumococcal carriage density, vaccine type density, non-vaccine type density, or the prevalence of antimicrobial resistance genes.ConclusionPNG infants experience dense and diverse pneumococcal colonisation with concurrent serotypes from 1 month of age. PCV13 had no impact on pneumococcal carriage density, even for vaccine serotypes. The low prevalence of vaccine serotypes, high pneumococcal carriage density and abundance of non-vaccine serotypes likely contribute to the lack of PCV13 impact on carriage in PNG infants. Indirect effects of the infant PCV programs are likely to be limited in PNG. Alternative vaccines with broader coverage should be considered.  相似文献   
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PurposeThyroid carcinoma (TC) is the most common endocrinal malignancy worldwide. Cyclin E2 (CCNE2), a member of the cyclin family, acts as a regulatory subunit of cyclin-dependent kinases (CDKs). It controls the transition of quiescent cells into the cell cycle, regulates the G1/S transition, promotes DNA replication, and activates CDK2. This study explored the role and potential molecular mechanisms of CCNE2 expression in TC tissues.Material/methodsImmunohistochemistry was used to evaluate the CCNE2 protein expression levels in TC. High-throughput data on CCNE2 in TC were obtained from RNA sequencing (RNA-seq), microarray, and literature data. The CCNE2 expression levels in TC were comprehensively assessed through an integrated analysis. Analyses of Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and protein–protein interaction (PPIs) data facilitated the investigation of the relative molecular mechanisms of CCNE2 in TC.ResultsThe immunohistochemical experiment showed a significant increase in the expression of CCNE2 in the TC tissues. For 505 TC and 59 non-cancerous samples from RNA-seq data, the area under the curve (AUC) was 0.8016 (95% confidence interval [CI] 0.742–0.8612; p<0.001). With another 14 microarrays, the pool standard mean difference [SMD] was 1.01 (95% CI [0.82–1.19]). The pooled SMD of CCNE2 was 1.12 (95% CI [0.60–1.64]), and the AUC was 0.87 (95% CI [0.84–0.90]) for 1157 TC samples and 366 non-cancerous thyroid samples from all possible sources. Nine hub genes were upregulated in TC.ConclusionsA high expression of CCNE2 may lead to carcinogenesis and the development of TC.  相似文献   
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目的:检测并分析苯丙芘诱导的口腔上皮细胞癌变过程中基因表达的变化,寻找在口腔上皮细胞癌变过程中起重要作用的基因。方法:使用课题组前期建立的一株永生化细胞系,以及经过苯丙芘诱导而逐步产生的具有成瘤性的肿瘤细胞系【首代成瘤细胞(HB-56P)及典型鳞状细胞癌细胞(HB-94P)】,通过Affymetrix U133 plus 2.0基因芯片。检测在永生化细胞(HIOEC)向成瘤细胞转化过程中的基因表达变化。使用GenSpring7.0进行标准化及单因素方差分析,通过Venn图分析差异基因在癌变不同阶段的变化,并进一步通过GO术语进行注释。对部分基因使用实时定量PCR在细胞系中进行了验证。结果:在HIOEC向HB-94P转化过程中,共有883条差异基因,大部分集中于肿瘤发生的早期阶段。差异基因主要涉及大分子代谢、信号传导等生物学过程。具有过渡金属离子结合能力、腺核苷酸结合能力及激酶活性。其蛋白产物主要是膜结合蛋白,位于核内或细胞骨架。IGFBP3、S100A8、MAP2K、KRT6B、GDF15和MET的表达基本符合芯片结果。结论:本研究检测了苯丙芘相关口腔上皮细胞癌变过程中基因表达的变化,为苯丙芘相关的口腔癌分子发病机制研究提供了基础。  相似文献   
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In a matter of a few days the murine tooth germ develops into a complex, mineralized, structure. Murine 30K microarrays were used to examine gene expression in the mandibular first molar tooth germs isolated at 15.5dpc and at 2DPN. Microarray results were validated using real-time RT-PCR. The results suggested that only 25 genes (3 without known functions) exhibited significantly higher expression at 15.5dpc compared to 2DPN. In contrast, almost 1400 genes exhibited significantly (P<0.015) higher expression at 2DPN compared to 15.5dpc, about half of which were genes with unknown functions. More than 50 of the 783 known genes exhibited higher than 10-fold increase in expression at 2DPN, amongst these were genes coding for enamel matrix proteins which were expressed several 100-fold higher at 2DPN. GO and KEGG analysis showed highly significant associations between families of the 783 known genes and cellular functions relating to energy metabolism, protein metabolism, regulation of cell division, cell growth and apoptosis. The use of bioinformatics analysis therefore yielded a functional profile in agreement with known differences in tissue morphology and cellular composition between these two stages. Such data is therefore useful in directing attention towards genes, or cellular activities, which likely are worthy of further studies as regards their involvement in odontogenesis.  相似文献   
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ObjectivesSjögren's syndrome (SS) is a chronic autoimmune disease characterized by inflammatory lesions in the salivary and lacrimal glands, which are caused by distinct lymphocytic infiltrates. Female non-obese diabetic (NOD) mice spontaneously develop inflammatory lesions of the salivary glands with SS-like pathological features. Previous studies have shown that MyD88, a crucial adaptor protein that activates innate immune signaling, affects lymphocytic infiltration, but its detailed role remains unclear. In this study, we investigated the role of MyD88 through gene expression profiling in the early phase of pathogenesis in the salivary glands of female NOD mice.MethodsSubmandibular glands collected from 10-week-old female wild-type and Myd88-deficient NOD mice were used for RNA preparation, followed by microarray analysis. The microarray dataset was analyzed to identify Myd88-dependent differentially expressed genes (DEGs). Data generated were used for GO enrichment, KEGG pathway, STRING database, and INTERFEROME database analyses.ResultsMyd88 deficiency was found to affect 230 DEGs, including SS-associated genes, such as Cxcl9 and Bpifa2. Most of the DEGs were identified as being involved in immunological processes. KEGG pathway analysis indicated that the DEGs were putatively involved in autoimmune diseases, such as systemic lupus erythematosus and rheumatoid arthritis. Furthermore, the DEGs included 149 interferon (IFN)-regulated genes.ConclusionsMyD88 is involved in the expression of specific genes associated with IFN-associated immunopathological processes in the salivary glands of NOD mice. Our findings are important for understanding the role of MyD88-dependent innate immune signaling in SS manifestation.  相似文献   
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Background

Early fetuses heal wounds without the formation of a scar. Many studies have attempted to explain this remarkable phenomenon. However, the exact mechanism remains unknown. Herein, we examine the predominant cell types of the epidermis and dermis—the keratinocyte and fibroblast—during different stages of fetal development to better understand the changes that lead to scarring wound repair versus regeneration.

Materials and methods

Keratinocytes and fibroblasts were harvested and cultured from the dorsal skin of time-dated BALB/c fetuses. Total RNA was isolated and microarray analysis was performed using chips with 42,000 genes. Significance analysis of microarrays was used to select genes with >2-fold expression differences with a false discovery rate <2. Enrichment analysis was performed on significant genes to identify differentially expressed pathways.

Results

By comparing the gene expression profile of keratinocytes from E16 versus E18 fetuses, we identified 24 genes that were downregulated at E16. Analysis of E16 and E18 fibroblasts revealed 522 differentially expressed genes. Enrichment analysis showed the top 20 signaling pathways that were downregulated in E16 keratinocytes and upregulated or downregulated in E16 fibroblasts.

Conclusions

Our data reveal 546 differentially expressed genes in keratinocytes and fibroblasts between the scarless and scarring transition. In addition, a total of 60 signaling pathways have been identified to be either upregulated or downregulated in these cell types. The genes and pathways recognized by our study may prove to be essential targets that may discriminate between fetal wound regeneration and adult wound repair.  相似文献   
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