Cardiac hypertrophy accompanied by maladaptive cardiac remodeling is the uppermost risk factor for the development of heart failure. Long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) have various biological functions, and their vital role in the regulation of cardiac hypertrophy still needs to be explored. In this study, we demonstrated that lncRNA Plscr4 was upregulated in hypertrophic mice hearts and in angiotensin II (Ang II)–treated cardiomyocytes. Next, we observed that overexpression of Plscr4 attenuated Ang II-induced cardiomyocyte hypertrophy. Conversely, the inhibition of Plscr4 gave rise to cardiomyocyte hypertrophy. Furthermore, overexpression of Plscr4 attenuated TAC (transverse aortic constriction)-induced cardiac hypertrophy. Finally, we demonstrated that Plscr4 acted as an endogenous sponge of miR-214 and forced expression of Plscr4 downregulated miR-214 expression to promote Mfn2 and attenuate hypertrophy. In contrast, knockdown of Plscr4 upregulated miR-214 to induce cardiomyocyte hypertrophy. Additionally, luciferase assay showed that miR-214 was the direct target of Plscr4, and overexpression of miR-214 counteracted the anti-hypertrophy effect of Plscr4. Collectively, these findings identify Plscr4 as a negative regulator of cardiac hypertrophy in vivo and in vitro due to its regulation of the miR-214-Mfn2 axis, suggesting that Plscr4 might act as a therapeutic target for the treatment of cardiac hypertrophy and heart failure.

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, fibrotic parenchymal lung disease of unknown etiology and lack effective interventions. Using a combination of in vitro and in vivo studies, we found that overexpression of YAP1, a key effector in the Hippo pathway, promoted cell proliferation, migration, and collagen production in lung fibroblasts. Furthermore, the pro-fibrotic action of YAP1 was mediated by transcriptional activation of Twist1 through interacting with its partner TEAD. In contrast, knockdown of YAP1 inhibited extracellular matrix (ECM) deposition, which ultimately ameliorated lung fibrosis in vitro and in vivo. Additionally, we constructed a dysregulated miRNA regulatory network that affects the expression of the Hippo pathway effectors in IPF and identified miR-15a, which is significantly down-regulated in IPF patients, as one of the most essential miRNAs regulating this pathway. Moreover, knockdown of miR-15a resulted in fibroblast activation and lung fibrosis through promoting Twist expression by targeting inhibition of YAP1. In contrast, therapeutic restoration of miR-15a inhibits fibrogenesis in lung fibroblast and abrogated BLM-induced lung fibrosis in mice. These results highlight a role for miR-15a/YAP1/Twist axis in IPF that offer novel strategies for the prevention and treatment of lung fibrosis.

The histone modification level has been shown to be related with gene activation and repression in stress-responsive process, but there is little information on the relationship between histone modification and cell cycle gene expression responsive to environmental cues. In this study, the function of histone modifications in mediating the transcriptional regulation of cell cycle genes under various types of stress was investigated in maize (Zea mays L.). Abiotic stresses all inhibit the growth of maize seedlings, and induce total acetylation level increase compared with the control group in maize roots. The positive and negative regulation of the expression of some cell cycle genes leads to perturbation of cell cycle progression in response to abiotic stresses. Chromatin immunoprecipitation analysis reveals that dynamic histone acetylation change in the promoter region of cell cycle genes is involved in the control of gene expression in response to external stress and different cell cycle genes have their own characteristic patterns for histone acetylation. The data also showed that the combinations of hyperacetylation and hypoacetylation states of specific lysine sites on the H3 and H4 tails on the promoter regions of cell cycle genes regulate specific cell cycle gene expression under abiotic stress conditions, thus resulting in prolonged cell cycle duration and an inhibitory effect on growth and development in maize seedlings.

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MicroRNAs (miRNAs) are endogenous small noncoding RNAs that negatively regulate gene expression at the posttranscriptional level and play an important role in carcinogenesis. Herein, we characterized the global expression of miRNA in distal gastric adenocarcinomas and determined if circulating miRNAs could be used as biomarkers for distal gastric adenocarcinoma. We used a microarray screening system to detect dysregulated miRNAs in distal gastric adenocarcinoma tissues. The expression of a subset of five aberrantly expressed miRNAs (miR-375, -196b, -204, -18b, and -93) were further quantified in an independent set of clinical samples of distal gastric adenocarcinoma by real-time quantitative RT-PCR (rt-qRT-PCR). We also used rt-qRT-PCR to investigate the expression levels of putative miRNA biomarkers in serum and tumor cell lines. In our study, the expression of a subset of microRNAs was altered in distal gastric adenocarcinoma compared to normal tissue, miR-375 was significantly downregulated in distal gastric adenocarcinoma tissues, to a level that was significantly lower than cardia adenocarcinoma (p < 0.05). The circulating serum levels of miR-375 in patients who had distal gastric adenocarcinoma were also much lower than normal controls (p < 0.001). As a biomarker, miR-375 yielded a receiver operating characteristic area under the curve of 0.835. The specificity and sensitivity was 80% and 85%, respectively, in the discrimination of distal gastric adenocarcinoma from control, at a normalized cutoff of 0.218. The expression of miR-375 was downregulated both in distal gastric adenocarcinoma tissues and serum of patients with distal gastric adenocarcinoma. These data suggest miR-375 is a potential biomarker for distal gastric adenocarcinoma.