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In consensus, myocardial infarction (MI) is defined as irreversible cell death secondary to prolonged ischemia in heart. The aim of our study was to evaluate the therapeutic potential of anti-fibrotic human Relaxin-expressing plasmid DNA with hypoxia response element (HRE) 12 copies (HR1) delivered by a dendrimer type PAM-ABP polymer G0 (HR1/G0) after MI on functional, hemodynamic, geometric, and cardiac extracellular matrix (ECM) remodeling in rats. HR1/G0 demonstrated significantly improved LV systolic function, hemodynamic parameters, and geometry on 1 wk and 4 wks after MI in rats, compared with I/R group. The resolution of regional wall motional abnormalities and the increased blood flow of infarct-related coronary artery supported functional improvements of HR1/G0. Furthermore, HR1/G0 polyplex showed favorable post-infarct cardiac ECM remodeling reflected on the favorable cardiac ECM compositions. Overall, this is the first study, which presented an advanced platform for the gene therapy that reverses adverse cardiac remodeling after MI with a HR1 gene delivered by a bioreducible dendrimer polymer in the cardiac ECM., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Purpose: Despite the widespread use of radiotherapy as a local and regional modality for the treatment of cancer, some non–small-cell lung cancers commonly develop resistance to radiation. We thus sought to clarify the molecular mechanisms underlying resistance to radiation. Methods and Materials: We established the radioresistant cell line H460R from radiosensitive parental H460 cells. To identify the radioresistance-related genes, we performed microarray analysis and selected several candidate genes. Results: Clonogenic and MTT assays showed that H460R was 10-fold more resistant to radiation than H460. Microarray analysis indicated that the expression levels of 1,463 genes were altered more than 1.5-fold in H460R compared with parental H460. To evaluate the putative functional role, we selected one interesting gene tumor protein p53-inducible protein 3 (TP53I3), because that this gene was significantly downregulated in radioresistant H460R cells and that it was predicted to link p53-dependent cell death signaling. Interestingly, messenger ribonucleic acid expression of TP53I3 differed in X-ray–irradiated H460 and H460R cells, and overexpression of TP53I3 significantly affected the cellular radiosensitivity of H460R cells. Conclusions: These results show that H460R may be useful in searching for candidate genes that are responsible for radioresistance and elucidating the molecular mechanism of radioresistance. [Copyright &y& Elsevier]

Abstract: The inhibitor of differentiation (Id) family of genes, which encodes negative regulators of basic helix-loop-helix transcription factors, has been implicated in diverse cellular processes such as proliferation, apoptosis, differentiation, and migration. However, the specific role of Id1 in titanium dioxide (TiO2)-induced lung injury has not been investigated. In the present study, we investigated whether TiO2 induces apoptosis in H1299 lung cancer cells and by which pathways. Based on the results of the LDH assay, dual staining with Annexin V-FITC and propidium iodide (PI), and RT-PCR analysis of apoptosis-related gene expression, TiO2 caused a dose- and time-dependent decrease in cell viability and appeared to involve both necrosis and apoptosis. Furthermore, Id1 expression was significantly reduced in TiO2-treated cells compared with control cells. To further investigate the functional role of Id1, cells were transduced with a recombinant adenovirus expressing Id1, and the effects on sensitivity to TiO2 were analyzed. Id1 overexpression led to the enhancement of cellular proliferation and reduced the sensitivity of H1299 cells to TiO2. Our results indicate that Id1 expression attenuates the degree of TiO2-induced cytotoxicity in lung cells. [Copyright &y& Elsevier]

Abstract: To elucidate the molecular mechanisms underlying the up-regulation of aldose reductase observed in many cancer cells, we investigated the signal transduction pathways mediating induction of aldose reductase gene expression by 12-O-tetradecanoylphorbol-13-acetate, a potent tumor promoter. A maximum of four-fold induction in aldose reductase mRNA was demonstrated in HeLa cells treated with 12-O-tetradecanoylphorbol-13-acetate. The increased level of aldose reductase transcript was accompanied by the elevated level of enzyme activity, and completely abolished in the presence of actinomycin D. Inhibitors of protein kinase C, bisindolylmaleimide I and calphostin C, as well as inhibitors of tyrosine kinase, genistein and tyrphostin A23, significantly attenuated 12-O-tetradecanoylphorbol-13-acetate-induced increase in aldose reductase mRNA. Blockade of the p38 mitogen-activated protein kinase pathway by SB203580 also suppressed 12-O-tetradecanoylphorbol-13-acetate-induced aldose reductase expression. The promoter activity of aldose reductase gene was significantly augmented in the cells treated with 12-O-tetradecanoylphorbol-13-acetate, but attenuated in the presence of bisindolylmaleimide I, tyrphostin A23 or SB203580. Pyrrolidinedithiocarbamate, a nuclear factor κB inhibitor, dose-dependently suppressed 12-O-tetradecanoylphorbol-13-acetate-induced increase in aldose reductase mRNA. 12-O-tetradecanoylphorbol-13-acetate augmented the DNA binding activity of nuclear factor κB and nuclear factor κB-dependent gene transcription, and these effects were attenuated by bisindolylmaleimide I or tyrphostin A23, but not by SB203580. Taken together, activation of protein kinase C and tyrosine kinase by 12-O-tetradecanoylphorbol-13-acetate elicits increased promoter activity of aldose reductase gene via nuclear factor κB. A p38 mitogen-activated protein kinase pathway, distinct from the tyrosine kinase pathway, may also take part in 12-O-tetradecanoylphorbol-13-acetate-induced increase in aldose reductase gene expression. [Copyright &y& Elsevier]