Long non-coding RNA BC002811 Promotes Gastric Cancer Metastasis by Regulating SOX2 Binding to the PTEN Promoter.

There is increasing evidence that long non-coding RNAs (lncRNAs) are involved in the pathogenesis and progression of gastric cancer (GC), however, the underlying mechanisms remain poorly understood. In this study, we identified lncRNA BC002811 as a critical regulator of GC development and progression. BC002811 was upregulated in GC tissues and cell lines, and that high expression of BC002811 was indicative of a reduction in overall survival of GC patients. Our research reveals that BC002811 promoted GC cell proliferation, migration, invasion, and inhibition of apoptosis in vitro, as well as accelerated tumor growth and metastasis in vivo. We also found that BC002811 upregulated MMP2 and MMP9 and promoted GC cell metastasis partially through downregulating PTEN expression. BC002811 may act as a molecular decoy for the transcription factor SOX2, thereby inhibiting the transcription of PTEN by blocking SOX2 binding to the PTEN promoter. Our study advances the understanding of the role of BC002811 in the pathogenesis of GC and provides new molecular targets for therapeutic intervention against GC metastasis.

DHA inhibits invasion and metastasis in NSCLC cells by interfering with CCL18/STAT3 signaling pathway.

Omega-3 has been proposed as an antitumor substance that suppresses the growth and metastasis of multiple types of tumor cells, including lung cancer, but the specific mechanisms involved remain obscure. Our previous studies showed that the expression of chemokine ligand 18 was related to the migration and metastasis of non-small cell lung cancer. Here, we aim to explore whether omega-3 inhibits invasion and metastasis of NSCLC by regulating the expression of CCL18. The expression of CCL18, metastasis- and epithelial-mesenchymal transition (EMT)-related genes at mRNA and protein levels in NSCLC cell lines were detected by RT-qPCR and Western blot, respectively. The metastatic and invasive capability of NSCLC cells were evaluated by scratch wound healing and Transwell assays, respectively. Our results showed that the level of CCL18 is positively associated with metastatic ability of NSCLC cells. Docosahexaenoic acid, an important long-chain, polyunsaturated omega-3 (n-3) fatty acid, significantly inhibited invasion and metastasis of NSCLC cells, and concomitantly downregulated the expression of metastasis- and EMT-related genes and p-STAT3 signaling pathway. Additionally, we found that DHA inhibited CCL18 expression in lung cancer cells, while overexpression of CCL18 effectively reversed DHA-mediated downregulation in the expression of metastasis- and EMT-related genes and p-STAT3 signaling as well as DHA-mediated inhibitory effect on metastasis and invasion of NSCLC cells. DHA inhibits NSCLC cell invasion and metastasis possibly through targeted inhibition of CCL18/ STAT3 signaling pathway and EMT process.

Integrated analysis of microRNA and transcription factors in the bone marrow of patients with acute monocytic leukemia.

Acutemonocytic leukemia (AMoL) is a distinct subtype of acute myeloid leukemia (AML) with poor prognosis. However, the molecular mechanisms and key regulators involved in the global regulation of gene expression levels in AMoL are poorly understood. In order to elucidate the role of microRNAs (miRNAs/miRs) and transcription factors (TFs) in AMoL pathogenesis at the network level, miRNA and TF expression level profiles were systematically analyzed by miRNA sequencing and TF array, respectively; this identified 285 differentially expressed miRNAs and 139 differentially expressed TFs in AMoL samples compared with controls. By combining expression level profile data and bioinformatics tools available for predicting TF and miRNA targets, a comprehensive AMoL-specific miRNA-TF-mediated regulatory network was constructed. A total of 26 miRNAs and 23 TFs were identified as hub nodes in the network. Among these hubs, miR-29b-3p, MYC, TP53 and NFKB1 were determined to be potential AMoL regulators, and were subsequently extracted to construct sub-networks. A hypothetical pathway model was also proposed for miR-29b-3p to reveal the potential co-regulatory mechanisms of miR-29b-3p, MYC, TP53 and NFKB1 in AMoL. The present study provided an effective approach to discover critical regulators via a comprehensive regulatory network in AMoL, in addition to enhancing understanding of the pathogenesis of this disease at the molecular level.

The inhibitory effect of tachyplesin I on thrombosis and its mechanisms.

Thrombotic diseases are major cause of cardiovascular diseases. This study was designed to investigate the effect of tachyplesin I on platelet aggregation and thrombosis. Platelet aggregation was analysed with a whole blood aggregometer. The mice were employed to investigate the effect of tachyplesin I on thrombosis in vivo. Tachyplesin I inhibited thrombin-induced platelet aggregation in a dose-dependent manner. Furthermore, tachyplesin I significantly reduced thrombosis in carrageenan-induced tail thrombosis model by intraperitoneal injection (0.1, 0.2 or 0.4 mg/kg) or intragastric administration (15, 30 or 60 mg/kg). Tachyplesin I also prolonged the bleeding time (BT) and clotting time (CT). The results revealed that tachyplesin I inhibited platelet aggregation and thrombosis by interfering the PI3K/AKT pathway. Tachyplesin I did not show significantly toxicity to mice under 300 mg/kg via intravenous injection. The results show that tachyplesin I inhibits thrombosis and has low toxicity. It is suggested that tachyplesin I has the potential to develop a new anti-thrombotic drug.

Galangin suppresses hepatocellular carcinoma cell proliferation by reversing the Warburg effect.

Hepatocellular carcinoma (HCC) is the sixth most common cancer. The Warburg effect is an important way by which HCC adapts to a hypoxic environment. The aim of the present study was to determine whether and how galangin reverses the Warburg effect in HCC cells. We treated three HCC cell lines, HepG2, Hep3B and PLC/PRF/5 with galangin for 24h, respectively. Cell proliferation was measured with MTT assay. Glucose uptake, lactate production and the oxygen consumption were measured. Pyruvate kinase activities were detected by measuring the consumption of NADH, and glycolytic pathway-related proteins were measured by Western blotting. The results showed that galangin suppressed proliferation of HCC cells, decreased glucose absorption and lactate production of HCC. In addition, galangin also gave rise to increased oxygen consumption in all three HCC cell lines. After treatment with galangin, the activity of pyruvate kinase was up-regulated and the expression levels of glycolytic pathway-related proteins were changed. These results suggest that galangin suppresses the Warburg effect in HCC cells, indicating that galangin might be a potential therapeutic agent for HCC.

Human glioma cells-conditioned medium promotes proliferation and migration of human bone marrow mesenchymal stromal cells in vitro.

PURPOSE: To investigate changes in cell proliferation and migration of human bone marrow-derived mesenchymal stromal cells (hMSCs) in glioma environment, in order to assess the tumorigenic risk of hMSCs in the clinical application to treat human gliomas. METHODS: hMSCs were obtained from normal adult persons and identified by their morphological characteristics and test of their stemness. The U251 glioma cell-conditioned medium (U251-CM) was obtained to simulate the human glioma environment in vitro. hMSCs were cultured in the U251-CM or the control medium in the same conditionzs and changes in cell proliferation and migration were detected by MTT assay and wound healing assay. RESULTS: The results of MTT assay showed that, compared with the control group, the proliferation of hMSCs cultured in U251-CM increased significantly, and the results of wound healing assay showed that the migration of hMSCs cultured in U251-CM also increased significantly. CONCLUSIONS: Human glioma cell-conditioned medium may promote the proliferation and migration of hMSCs, and we are concerned about the tumorigenic risk of hMSCs in glioma environment before their clinical application.

Integrated analysis of microRNA and transcription factor reveals important regulators and regulatory motifs in adult B-cell acute lymphoblastic leukemia.

B-cell acute lymphoblastic leukemia (B­ALL) is an aggressive hematological malignancy and a leading cause of cancer-related mortality in children and young adults. The molecular mechanisms involved in the regulation of its gene expression has yet to be fully elucidated. In the present study, we performed large scale expression profiling of microRNA (miRNA) and transcription factor (TF) by Illumina deep­sequencing and TF array technology, respectively, and identified 291 differentially expressed miRNAs and 201 differentially expressed TFs in adult B­ALL samples relative to their controls. After integrating expression profile data with computational prediction of miRNA and TF targets from different databases, we construct a comprehensive miRNA­TF regulatory network specifically for adult B­ALL. Network function analysis revealed 25 significantly enriched pathways, four pathways are well­known to be involved in B­ALL, such as PI3K­Akt signaling pathway, Jak­STAT signaling pathway, Ras signaling pathway and cell cycle pathway. By analyzing the network topology, we identified 28 hub miRNAs and 19 hub TFs in the network, and found nine potential B­ALL regulators among these hub nodes. We also constructed a Jak­STAT signaling sub­network for B­ALL. Based on the sub­network analysis and literature survey, we proposed a cellular model to discuss MYC/miR­15a­5p/FLT3 feed-forward loop (FFL) with Jak­STAT signaling pathway in B­ALL. These findings enhance our understanding of this disease at the molecular level, as well as provide putative therapeutic targets for B-ALL.

Galangin Induces Autophagy via Deacetylation of LC3 by SIRT1 in HepG2 Cells.

Galangin suppresses proliferation and induces apoptosis and autophagy in hepatocellular carcinoma (HCC) cells, but the precise mechanism is not clear. In this study, we demonstrated that galangin induced autophagy, enhanced the binding of SIRT1-LC3 and reduced the acetylation of endogenous LC3 in HepG2 cells. But this autophagy was inhibited by inactivation of SIRT1 meanwhile, galangin failed to reduce the acetylation of endogenous LC3 after SIRT1 was knocked-down. Collectively, these findings demonstrate a new mechanism by which galangin induces autophagy via the deacetylation of endogenous LC3 by SIRT1.

Galangin suppresses HepG2 cell proliferation by activating the TGF-ß receptor/Smad pathway.

Galangin can suppress hepatocellular carcinoma (HCC) cell proliferation. In this study, we demonstrated that galangin induced autophagy by activating the transforming growth factor (TGF)-ß receptor/Smad pathway and increased TGF-ß receptor I (RI), TGF-ßRII, Smad1, Smad2, Smad3 and Smad4 levels but decreased Smad6 and Smad7 levels. Autophagy induced by galangin appears to depend on the TGF-ß receptor/Smad signalling pathway because the down-regulation of Smad4 by siRNA or inhibition of TGF-ß receptor activation by LY2109761 blocked galangin-induced autophagy. The down-regulation of Beclin1, autophagy-related gene (ATG) 16L, ATG12 and ATG3 restored HepG2 cell proliferation and prevented galangin-induced apoptosis. Our findings indicate a novel mechanism for galangin-induced autophagy via activation of the TGF-ß receptor/Smad pathway. The induction of autophagy thus reflects the anti-proliferation effect of galangin on HCC cells.

Galangin inhibits proliferation of hepatocellular carcinoma cells by inducing endoplasmic reticulum stress.

Prolonged endoplasmic reticulum (ER) stress may activate apoptotic pathways in cancer cells. It is suggested that ER stress has the potential of enhancing tumor death in cancer therapy. Galangin, a flavonol derived from Alpinia officinarum Hance, has been shown to suppress the proliferation of hepatocellular carcinoma cells (HCC). The aim of this study was to determine whether galangin was able to induce ER stress in HepG2, Hep3B and PLC/PRF/5 cells. The proliferation of HCC was tested by MTT method. Intracellular Ca(2+) levels were measured with Fluo3-AM.The proteins levels of GRP94, GRP78 and CHOP were detected by Western blot. To further understand the anti-HCC mechanism of galangin, mitogen-activated protein kinases (MAPKs) were detected. The results showed that galangin treatment induced ER stress was evidenced by increased protein levels of GRP94, GRP78 and CHOP, as well as increased free cytosolic Ca(2+) concentration. ER stress inhibitor 4-PBA and CHOP siRNA blocked significantly galangin-induced ER in all three cell lines. Further experiments showed that MAPKs involved in ER stress induced by galangin. In summary, galangin is identified as a stimulator of ER stress to suppress the proliferation of HCC, and may be used as a potential anti-cancer agent.

Galangin induces apoptosis of hepatocellular carcinoma cells via the mitochondrial pathway.

AIM: To investigate the mechanism by which galangin, a polyphenolic compound derived from medicinal herbs, induces apoptosis of hepatocellular carcinoma (HCC) cells. METHODS: The 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assay was used to measure cell viability. Apoptosis was evaluated by in situ uptake of propidium iodide and Hoechst 33258 and was then detected by fluorescence microscopy. Protein expressions were detected by Western blotting. To confirm the apoptotic pathway mediated by galangin, cells were transfected by bcl-2 gene to overexpress Bcl-2 or siRNA to down-regulate Bcl-2 expression. RESULTS: Galangin (46.25-370.0 micromol/L) exerted an anti-proliferative effect, induced apoptosis, and decreased mitochondrial membrane potential in a dose and time-dependent manner. Treatment with galangin induced apoptosis by translocating the pro-apoptotic protein Bax to the mitochondria, which released apoptosis-inducing factor and cytochrome c into the cytosol. Overexpression of Bcl-2 attenuated galangin-induced HepG2 cell apoptosis, while decreasing Bcl-2 expression enhanced galangin-induced cell apoptosis. CONCLUSION: Our data suggests that galangin mediates apoptosis through a mitochondrial pathway, and may be a potential chemotherapeutic drug for the treatment of HCC.