Temporal expression profiles of microRNAs associated with acute phase of brain ischemia in gerbil hippocampus.

Neuroprotective therapeutic potential for restoring dysregulated microRNA (miRNA) expression has previously been demonstrated in a gerbil cerebral infarction model. However, since temporal changes in miRNA expression profiles following stroke onset are unknown, miRNAs proving to be useful therapeutic targets have yet to be identified. We evaluated cognitive function, hippocampal neuronal cell death, and microarray-based miRNA expression profiles at 5, 9, 18, 36, and 72 h after 5-min whole brain ischemia in gerbils. A decline in cognitive function occurred in parallel with increased neuronal cell death 36-72 h after ischemia. The Jonckheere-Terpstra test was used to analyze miRNA expression trends 5-72 h after ischemia. The expression levels of 63 miRNAs were significantly upregulated, whereas 32 miRNAs were significantly downregulated, monotonically. Of the 32 monotonically downregulated miRNAs, 18 showed the largest decrease in expression 5-9 h after ischemia. A subset of these dysregulated miRNAs (miR-378a-5p, miR-204-5p, miR-34c-5p, miR-211-5p, miR-34b-3p, and miR-199b-3p) could be associated with brain ischemia and neuropsychiatric disorders.

Role of Mir-452-5p Overexpression in Epithelial-Mesenchymal Transition (EMT) in Early-stage Colorectal Cancer.

BACKGROUND/AIM: The microRNA miR-452-5p holds a critical role in the progression of multiple tumor formations, but there is limited understanding regarding the epithelial-mesenchymal transition (EMT) progression and its underlying mechanisms in the early-stage colorectal cancer (CRC). We aimed to explore the change in miRNA expression in early-stage CRC and examine the role of these miRNAs in CRC. MATERIALS AND METHODS: The expression levels of miR-452-5p in tissues and cells of early-stage CRC were determined by real-time quantitative polymerase chain reaction. Additionally, the biological effects of miR-452-5p on CRC were investigated by in vitro functional experiments. RESULTS: The expression levels of miR-452-5p were found increased in early-stage CRC tissue. We found that miR-452-5p promoted CRC cell proliferation but inhibited epithelial-mesenchymal transition. Furthermore, miR-452-5p promoted cell proliferation through activation of the extracellular signal-regulated kinase pathway, and inhibited cell invasion through suppression of Slug (Snail2) expression and up-regulation of E-cadherin expression. CONCLUSION: The expression of miR-452-5p is up-regulated in early CRC and suppresses epithelial-mesenchymal transition in CRC. These discoveries suggest that miR-452-5p has the potential to serve as a viable therapeutic target for CRC.

Antitumor Effect of Galectin-9 on Cell Proliferation and Tumor Growth of Human Duodenal Adenocarcinoma Cells.

BACKGROUND/AIM: Galectin-9 (Gal-9) induces tumor cell apoptosis in lymphoma and other malignant cell types. Duodenal adenocarcinoma is a rare malignancy, and there are insufficient data to determine a standard therapeutic approach. Here, we investigated the antitumor effect of Gal-9 in HuTu-80 duodenal adenocarcinoma cells. MATERIALS AND METHODS: Cell proliferation was examined in HuTu-80 cells using a Cell Counting Kit-8 assay. Cell cycle analysis, apoptosis array, and microRNA expression analysis were performed to identify the effect of Gal-9 on HuTu-80 cells. The antitumor effect of Gal-9 was also examined using xenograft mouse models. RESULTS: Gal-9 suppressed the proliferation of HuTu-80 via blockade of the G0 to G1 cell cycle transition. This blockade was accompanied by a strong decrease in cyclin D1 and phosphorylated Rb, suggesting a G1 arrest. Additionally, Gal-9 induced apoptosis, and the expression of cleaved caspase-3 was increased in Gal-9-treated HuTu-80 cells according to the apoptosis array. MiRNA microarrays revealed that Gal-9 altered the expression of miRNAs in HuTu-80 cells. CONCLUSION: These data demonstrate the therapeutic potential of Gal-9 and provide molecular mechanistic insights into its antitumor effect in HuTu-80 cells.

Age­related brainstem degeneration through microRNA modulation in mice.

Histopathological changes occur in the brainstem during the early stages of Alzheimer's disease (AD), with the pathological changes of the brain lesions ascending progressively in accordance with the Braak staging system. The senescence­accelerated mouse prone 8 (SAMP8) mouse model has been previously used as a model of age­dependent neurodegenerative diseases, including AD. In the present study, microRNAs (miRNAs) that were upregulated or downregulated in SAMP8 brainstems were identified using miRNA profiling of samples obtained from miRNA arrays. The preliminary stage of cognitive dysfunction was examined using male 5­month­old SAMP8 mice, with age­matched senescence­accelerated mouse resistant 1 mice as controls. A Y­maze alternation test was performed to assess short­term working memory and miRNA profiling was performed in each region of the dissected brain (brainstem, hippocampus and cerebral cortex). SAMP8 mice tended to be hyperactive, but short­term working memory was preserved. Two miRNAs were upregulated (miR­491­5p and miR­764­5p) and two were downregulated (miR­30e­3p and miR­323­3p) in SAMP8 brainstems. In SAMP8 mice, the expression level of upregulated miRNAs were the highest in the brainstem, wherein age­related brain degeneration occurs early. It was demonstrated that the order of specific miRNA expression levels corresponded to the progression order of age­related brain degeneration. Differentially expressed miRNAs regulate multiple processes, including neuronal cell death and neuron formation. Changes in miRNA expression may result in the induction of target proteins during the early stages of neurodegeneration in the brainstem. These findings suggest that studying altered miRNA expression may provide molecular evidence for early age­related neuropathological changes.

Pegylated interferon therapy-related microRNA-6126 downregulates sodium taurocholate cotransporting polypeptide expression in hepatocytes.

Hepatitis B virus (HBV) infection is one of the most serious global health problems. Our previous data using an in vitro assay revealed that miR-6126 suppressed the extracellular HBs antigen level, suggesting that miR-6126 had potential to suppress viral activity of HBV. In the current study, we aimed to clarify whether miR-6126 downregulated the expression level of sodium taurocholate cotransporting polypeptide (NTCP), a host cell receptor required for HBV entry. In brief, HepG2-NTCP cells were utilized to evaluate the expression level of NTCP and the PreS1 attachment to NTCP after transfection with miR-6126. The protein expression level of NTCP was evaluated using Western blot analysis and immunostaining. In addition to HepG2-NTCP cells, PXB cells were also utilized to validate inhibitory effect of miR-6126 on PreS1 attachment. The HBs antigen level in the culture supernatant was measured to evaluate reduction of HBV entry into hepatocytes. The stability of NTCP mRNA was evaluated to ascertain the cause of the downregulation of NTCP mRNA. The expression profile of messenger RNAs was evaluated using next-generation sequencing to search for direct targets of miR-6126. Consequently, transfection of miR-6126 decreased the NTCP expression level in HepG2-NTCP cells. Attachment of the PreS1 probe on the cell surface decreased in HepG2-NTCP cells and PXB cells, primary human hepatocytes. HBs antigen level in the culture supernatant also declined in PXB cells. Stability of NTCP mRNA was reduced by miR-6126 transfection in HepG2 cells. In conclusion, miR-6126 downregulated the expression of NTCP mRNA, which contributed to the inhibition of HBV entry into hepatocytes exerted by miR-6126.

MicroRNA profiles following telmisartan treatment in pancreatic ductal adenocarcinoma cells.

Background: Pancreatic ductal adenocarcinoma (PDAC) is the most devastating of all cancers with an extremely poor prognosis. It has few effective and reliable therapeutic strategies. Telmisartan, a widely used antihypertensive drug, is an angiotensin II type 1 (AT1) receptor blocker (ARB). Telmisartan inhibits cancer cell proliferation, but the underlying mechanisms in PDAC, remain unknown. Material and Methods: In the present study, we evaluated the effects of telmisartan on human PDAC cell proliferation in vitro. We assessed the effects of telmisartan on human PDAC cells using the cell lines PK-1 and PANC-1. Results: Telmisartan inhibited the proliferation of these cells via blockade of the G0 to G1 cell cycle transition. This was accompanied by a strong decrease in cyclin D1. Telmisartan was also shown by receptor tyrosine kinase and angiogenesis arrays to reduce the phosphorylation of epidermal growth factor receptor (EGFR), and miRNA expression was markedly altered by telmisartan in PK-1 cells. Conclusion: In conclusion, telmisartan inhibits human PDAC cell proliferation by inducing cell cycle arrest. Furthermore, telmisartan significantly altered miRNA expression in vitro. Taken together, our study demonstrated the therapeutic potential of telmisartan and provides molecular mechanistic insights into its anti-tumor effect on PDAC cells.

Exendin-4 Increases Scavenger Receptor Class BI Expression via Activation of AMPK/FoxO1 in Human Vascular Endothelial Cells.

Glucagon-like peptide-1 receptor agonist (GLP-1RA) has been clinically proven to protect endothelial function. Previously, we demonstrated that endothelial NO synthase (eNOS) was activated by high-density lipoprotein (HDL) via its scavenger receptor of the B class/human homologue of SR-BI, CD36 and LIMPII analogous-1(hSR-BI/CLA-1). Here, we investigated the effect of GLP-1RA and exendin-4 on the expression of hSR-BI/CLA-1 in HUVECs. Our results confirmed that GLP-1R was expressed in HUVECs by PCR and exendin-4 significantly enhanced HDL-induced eNOS activation. Next, exendin-4 increased the expression of hSR-BI/CLA-1 and a blockade of GLP-1R cancelled this effect. Further, the hSR-BI/CLA-1 transcriptional activity was enhanced by exendin-4, which was diminished by the inhibition of AMPK or dominant-negative AMPK-α-subunit. Moreover, AMPK was phosphorylated by the activation of GLP-1R. Next, ChIP assay demonstrated that exendin-4 increased the FoxO1-binding in the hSR-BI/CLA-1 promoter by upregulation of FoxO1. Mutation of FoxO1-binding or silencing of FoxO1 cancelled the effect of exendin-4 on hSR-BI/CLA-1 expression. Exendin-4 reduced FoxO1 phosphorylation and induced its nuclear accumulation, while this effect was altered by the blocking of GLP-1R or inhibition of AMPK pathway. In summary, our results proved that exendin-4 increased hSR-BI/CLA-1 expression via the AMPK/FoxO1 pathway to activate eNOS, providing a basic mechanism underlining the protective effect of GLP-1RA on endothelial function.

Effect of Lenvatinib treatment on the cell cycle and microRNA profile in hepatocellular carcinoma cells.

Lenvatinib is a tyrosine kinase receptor inhibitor used to treat unresectable hepatocellular carcinoma (HCC). In this study, we investigated the antitumor effects of Lenvatinib treatment on HCC cell lines. Proliferation was examined in four HCC cell lines (HuH-7, Hep3B, Li-7, and PLC/PRF/5) using Cell Counting Kit-8 assays. Xenograft mouse models were used to assess the effects of Lenvatinib in vivo. Cell cycle, western blotting, and microRNA (miRNA) expression analyses were performed to identify the antitumor inhibitory potential of Lenvatinib on HCC cells. Lenvatinib treatment suppressed proliferation of HuH-7 and Hep3B, but not Li-7 and PLC/PRF/5 cells and induced G0/G1 cell cycle arrest and cyclin D1 downregulation in Lenvatinib-sensitive cells. Lenvatinib treatment also reduced tumor growth in HuH-7 xenograft mouse models. miRNA microarrays revealed that Lenvatinib treatment altered the expression of miRNAs in HuH7 cells and exosomes. Our results demonstrated the therapeutic potential of Lenvatinib and provide molecular mechanistic insights into its antitumor effects for treating HCC.

Effect of Aspirin on G0/G1 Cell Cycle Arrest and microRNA Signatures in Pancreatic Adenocarcinoma Cells.

BACKGROUND/AIM: Anti-inflammatory drugs, such as aspirin, have attracted attention as anticancer agents that can be applied to standard chemotherapy for pancreatic cancer. This study aimed to examine the antitumour effects and possible fundamental mechanisms of aspirin in pancreatic cancer cells. MATERIALS AND METHODS: We appraised the antitumour effects of aspirin on cell proliferation and tumour growth, cell cycle distribution, apoptosis, signalling pathways, angiogenesis-related proteins, and phosphorylated receptor tyrosine kinases (p-RTKs) and identify miRNAs associated with its antitumour effects. RESULTS: Aspirin inhibited cell proliferation in pancreatic cancer cell lines and induced G0/G1 cell cycle arrest by decreasing the expression of cyclin D1. Aspirin inactivated glycogen synthase kinase (GSK)-3ß but had no effect on the p38 mitogen-activated protein kinase (MAPK) pathway, p-RTKs, or angiogenesis-related molecules. Aspirin treatment statistically increased the expression of 274 miRNAs in PANC-1 cells and 30 miRNAs in PK-8 cells and suppressed the expression of 294 miRNAs in PANC-1 cells and 13 miRNAs in PK-8 cells. CONCLUSION: Aspirin inhibited the proliferation of pancreatic cancer cells and induced cell cycle arrest. Aspirin also inactivated GSK-3ß but not the p38 MAPK pathway. Thus, aspirin may be used in combination with chemotherapeutic agents for pancreatic cancer.

Ipragliflozin attenuates non-alcoholic steatohepatitis development in an animal model.

Non-alcoholic steatohepatitis (NASH) is a common chronic liver disease with no decisive treatment. The sodium glucose cotransporter 2 (SGLT2) inhibitor ipragliflozin was developed as a new oral hypoglycemic drug, which can improve NASH via an insulin-independent glucose-lowering effect by inhibiting glucose reabsorption in the renal proximal tubules. However, ipragliflozin appears to modulate steatosis or inflammation via different pathways. To elucidate the new mechanism of ipragliflozin for the treatment of NASH, we evaluated its effects in a NASH mouse model (STAM mice) with beta cell depletion, and compared the expression of microRNAs (miRNAs) in STAM mice treated with or without ipragliflozin (16.7 µg/day for 5 weeks). Ipragliflozin reduced aspartate transaminase and alanine aminotransferase levels, along with reduced hepatic steatosis, hepatocyte ballooning, lobular inflammation, and liver fibrosis. In addition, ipragliflozin upregulated mitochondrial transport-related and antioxidant defensive system-related genes in the liver. Among 2555 mouse miRNA probes, miR-19b-3p was commonly differentially expressed with ipragliflozin treatment for 5 weeks in both the liver and serum but in different directions, with a decrease in the liver and increase in the serum. Therefore, ipragliflozin can improve NASH development likely through the antioxidative stress pathway and by regulating miR-19b-3p.

Characterization of Cisplatin Effects in Lenvatinib-resistant Hepatocellular Carcinoma Cells.

BACKGROUND/AIM: Drug resistance to molecular targeted agents, such as lenvatinib, is an important issue. The aim of this study was to explore the mechanism of lenvatinib resistance and to investigate potential drugs that may improve the treatment of lenvatinib-resistant (LR) hepatocellular carcinoma (HCC). MATERIALS AND METHODS: LR cells were developed by long-term culture under lenvatinib exposure. We analyzed the biological characteristics of LR cells in vitro, and investigated the antitumor effects and endogenous mechanisms of cisplatin in LR cells. RESULTS: The proliferative potential of LR cells was enhanced by activation of ERK signaling and changes in several miRNAs. Cisplatin inhibited cell proliferation of LR cells and induced G2/M cell cycle arrest. Furthermore, cisplatin triggered the DNA damage response, via the ATM/ATR-Chk1/Chk2 signaling pathway. CONCLUSION: Proliferation of LR cells was induced upon ERK signaling activation. Cisplatin exerted antitumor effects in LR cells and was involved in the regulation of miRNAs associated with drug resistance.

Antitumor Effect of Regorafenib on MicroRNA Expression in Hepatocellular Carcinoma Cell Lines.

Hepatocellular carcinoma (HCC) is the most common primary malignancy of the liver and is one of the leading causes of cancer-related deaths worldwide. Regorafenib, a multi-kinase inhibitor, is used as a second-line treatment for advanced HCC. Here, we aimed to investigate the mechanism of the antitumor effect of regorafenib on HCC and evaluate altered microRNA (miRNA) expression. Cell proliferation was examined in six HCC cell lines (HuH-7, HepG2, HLF, PLC/PRF/5, Hep3B, and Li-7) using the Cell Counting Kit-8 assay. Xenografted mouse models were used to assess the effects of regorafenib in vivo. Cell cycle analysis, western blotting analysis, and miRNA expression analysis were performed to identify the antitumor inhibitory potential of regorafenib on HCC cells. Regorafenib suppressed proliferation in HuH-7 cell and induced G0/G1 cell cycle arrest and cyclin D1 downregulation in regorafenib-sensitive cells. During miRNA analysis, miRNA molecules associated with the antitumor effect of regorafenib were found. Regorafenib suppresses cell proliferation and tumor growth in HCC by decreasing cyclin D1 via alterations in intracellular and exosomal miRNAs in HCC.

A cerebrospinal fluid microRNA analysis: Progressive supranuclear palsy.

Progressive supranuclear palsy (PSP) is a neurodegenerative tauopathy described as a syndrome of postural instability, supranuclear vertical gaze palsy, dysarthria, dystonic rigidity of the neck and trunk, dementia, and pseudobulbar palsy. The clinical diagnosis of PSP is often difficult because there are no established biomarkers, and diagnosis is currently based on clinical and imaging findings. Furthermore, the etiology and pathogenesis of PSP remain unknown. Dysregulation of microRNAs (miRNAs/miRs) has been reported to serve an important role in neurodegenerative diseases. However, the miRNA profiles of patients with PSP are rarely reported. The present study aimed to examine cerebrospinal fluid miRNAs, which are considered to be more sensitive indicators of changes in the brain, to elucidate the pathophysiology of PSP and to establish specific biomarkers for diagnosis. The present study used a microarray chip containing 2,632 miRNAs to examine cerebrospinal fluid miRNA expression levels in 11 patients with PSP aged 68­82 years. A total of 8 age­ and sex­matched controls were also included. A total of 38 miRNAs were significantly upregulated and one miRNA was significantly downregulated in the cerebrospinal fluid of patients with PSP. The patients were divided into two groups based on disease stage (early onset and advanced), and changes in miRNA expression were examined. The miRNAs that were most significantly upregulated or downregulated in the early onset group were miR­204­3p, miR­873­3p and miR­6840­5p. The target genes of these miRNAs were associated with molecules related to the ubiquitin­proteasome system and autophagy pathway. Furthermore, these miRNAs were found to target genes that have been reported to have epigenetic changes following an epigenome­wide association study of brain tissues of patients with PSP. This suggested that these miRNAs and genes may have some involvement in the pathogenesis of PSP. However, the sample size of the present study was small; therefore, a greater number of patients with PSP should be examined in future studies.

Evaluating the Effect of Lenvatinib on Sorafenib-Resistant Hepatocellular Carcinoma Cells.

Hepatocellular carcinoma (HCC) is one of the major causes of cancer-related deaths worldwide. Sorafenib has been used as a first-line systemic treatment for over a decade. However, resistance to sorafenib limits patient response and presents a major hurdle during HCC treatment. Lenvatinib has been approved as a first-line systemic treatment for advanced HCC and is the first agent to achieve non-inferiority against sorafenib. Therefore, in the present study, we evaluated the inhibition efficacy of lenvatinib in sorafenib-resistant HCC cells. Only a few studies have been conducted on this topic. Two human HCC cell lines, Huh-7 and Hep-3B, were used to establish sorafenib resistance, and in vitro and in vivo studies were employed. Lenvatinib suppressed sorafenib-resistant HCC cell proliferation mainly by inducing G1 cell cycle arrest through ERK signaling. Hep-3B sorafenib-resistant cells showed partial cross-resistance to lenvatinib, possibly due to the contribution of poor autophagic responsiveness. Overall, the findings suggest that the underlying mechanism of lenvatinib in overcoming sorafenib resistance in HCC involves FGFR4-ERK signaling. Lenvatinib may be a suitable second-line therapy for unresectable HCC patients who have developed sorafenib resistance and express FGFR4.

Oxidized LDL Downregulates ABCA1 Expression via MEK/ERK/LXR Pathway in INS-1 Cells.

Impaired insulin secretion is one of the main causes of type 2 diabetes. Cholesterol accumulation-induced lipotoxicity contributes to impaired insulin secretion in pancreatic beta cells. However, the detailed mechanism in this process remains unclear. In this study, we proved that oxidized low-density lipoprotein (OxLDL) reduced insulin content, decreased PDX-1 expression, and impaired glucose-stimulated insulin secretion (GSIS) in INS-1 cells, which were rescued by addition of high-density lipoprotein (HDL). OxLDL receptors and cholesterol content were increased by OxLDL. Consistently, OxLDL suppressed cholesterol transporter ABCA1 expression and transcription in a dose-dependent and time-dependent manner. Inhibition of MEK by its specific inhibitor, PD98059, altered the effect of OxLDL on ABCA1 transcription and activation of ERK. Next, chromatin immunoprecipitation assay demonstrated that liver X receptor (LXR) could directly bind to ABCA1 promoter and this binding was inhibited by OxLDL. Furthermore, OxLDL decreased the nuclear LXR expression, which was prevented by HDL. LXR-enhanced ABCA1 transcription was suppressed by OxLDL, and the effect was cancelled by mutation of the LXR-binding sites. In summary, our study shows that OxLDL down-regulates ABCA1 expression by MEK/ERK/LXR pathway, leading to cholesterol accumulation in INS-1 cells, which may result in impaired insulin synthesis and GSIS.

MicroRNA Expression Profiles in Superficial Esophageal Squamous Cell Carcinoma before Endoscopic Submucosal Dissection: A Pilot Study.

Esophageal squamous cell carcinoma (ESCC) has a poor prognosis when diagnosed at an advanced stage, and early detection and treatment are essential to improve survival. However, intraobserver and interobserver variation make the diagnosis of superficial ESCC difficult, and suitable biomarkers are urgently needed. Here, we compared the microRNA (miRNA) expression profiles of superficial ESCC tissues and adjacent normal tissues obtained immediately before esophageal endoscopic submucosal dissection. We found that ESCC and normal tissues differed in their miRNA expression profiles. In particular, miR-21-5p and miR-146b-5p were significantly upregulated and miR-210-3p was significantly downregulated in tumor tissues compared with normal tissues. We also detected significant associations between miRNA expression and ESCC invasion depth and lymphovascular invasion. The same differential expression of miR-21-5p, miR-146b-5p, and miR-210-3p was detected in ESCC cell lines compared with normal esophageal epithelial cells in vitro. However, transfection of ESCC cells with miR-210-3p and miR-21-5p mimics or inhibitors had partial effects on cell proliferation and invasion in vitro. These results indicate that miRNA expression is significantly deregulated in superficial ESCC, and suggest that the potential contribution of differentially expressed miRNAs to the malignant phenotype should be further investigated.

Galectin­9 suppresses the tumor growth of colon cancer in vitro and in vivo.

Colon cancer is the second leading cause of cancer­related mortality worldwide, and the prognosis of advanced colon cancer has remained poor in recent years. Galectin­9 (Gal­9) is a tandem­repeat type galectin that has recently been shown to exert antiproliferative effects on various types of cancer cells. The present study aimed to assess the effects of Gal­9 on human colon and colorectal cancer cells in vitro and in vivo, as well as to evaluate the microRNAs (miRNAs/miRs) associated with the antitumor effects of Gal­9. We examined the ability of Gal­9 to inhibit cell proliferation via apoptosis, and the effects of Gal­9 on cell cycle­related molecules in various human colon and colorectal cancer cell lines. In addition, Gal­9­mediated changes in activated tyrosine kinase receptors and angiogenic molecules were assessed using protein array chips in colon and colorectal cancer cells. Moreover, miRNA array analysis was performed to examine Gal­9­induced miRNA expression profiles. We also elucidated if Gal­9 inhibited tumor growth in a murine in vivo model. We found that Gal­9 suppressed the cell proliferation of colon cancer cell lines in vitro and in vivo. Our data further revealed that Gal­9 increased caspase­cleaved keratin 18 levels in Gal­9­treated colon cancer cells. In addition, Gal­9 enhanced the phosphorylation of ALK, DDR1, and EphA10 proteins. Furthermore, the miRNA expression levels, such as miR­1246, miR­15b­5p, and miR­1237, were markedly altered by Gal­9 treatment in vitro and in vivo. In conclusion, Gal­9 suppresses the cell proliferation of human colon cancer by inducing apoptosis, and these findings suggest that Gal­9 can be a potential therapeutic target in the treatment of colon cancer.

AGEs inhibit scavenger receptor class B type I gene expression via Smad1 in HUVECs.

Vascular complications are the main cause of morbidity and mortality in diabetic patients, and advanced glycation end products (AGEs) play a critical role in promoting diabetic vascular dysfunction. The human homolog of scavenger receptor class B type I (SR-BI), CD36, and LIMPII analog-1 (hSR-BI/CLA-1) facilitates the cellular uptake of cholesterol from HDL. In endothelial cells, HDL activates endothelial nitric oxide synthase (eNOS) via hSR-BI/CLA-1. In this study, we elucidated the effects of AGEs on hSR-BI/CLA-1 expression in human umbilical vein endothelial cells (HUVECs). HSR-BI/CLA-1 expression was examined by real-time PCR, western blot analysis, and reporter gene assay in HUVECs incubated with AGEs. eNOS activity was assessed by detecting the phosphorylation (Ser 1179) of eNOS. Our results showed that AGEs decreased the endogenous expression of hSR-BI/CLA-1. AGEs also inhibited the activity of the hSR-BI/CLA-1 promoter and its mRNA expression via receptor RAGE. We identified the binding site for Smad1 on the hSR-BI/CLA-1 promoter: Smad1 bound to its promoter. AGE treatment stimulated the transcriptional activity of Smad1, and mutation of the Smad1 binding site inhibited the effect of AGEs on the hSR-BI/CLA-1 promoter. HDL-treatment enhanced the phosphorylation of eNOS at Ser 1179, but pretreatment with AGEs inhibited the phosphorylation of eNOS Ser 1179. These results suggested that AGEs downregulate the expression of the endothelial hSR-BI/CLA-1 via the Smad1 pathway, which may be a therapeutic target for diabetic endothelial dysfunction.

Association between microRNA-527 and glypican-3 in hepatocellular carcinoma.

The present study aimed to identify the specific microRNAs (miRNAs/miRs) and their corresponding target genes involved in hepatocellular carcinomas (HCCs). Microarray analysis was performed to examine the miRNA expression profiles of four paired HCC and corresponding non-cancerous (N) liver tissues using 985 miRNA probes. The Human miRNA Target database was used to identify the target genes of differentially expressed miRNAs between the HCC and N tissues. The protein expression levels of target genes in the HCC tissues and cell lines were evaluated using western blotting. miRNA-mediated suppression of target gene expression was evaluated by transiently transfecting the miRNA into the HCC cell lines. Of the 985 miRNAs evaluated, four miRNAs were differentially expressed (three upregulated and one downregulated miRNAs). Of these four miRNAs, miRNA-527 was highly downregulated in the HCC tissues. Glypican-3 (GPC-3) was predicted as a target gene of miRNA-527. Western blotting revealed that GPC-3 protein is highly expressed in the HCC tissues and HCC cell lines compared with N and normal cell lines. Transfection with miR-527 resulted in suppression of GPC-3 protein expression in the Cos7 cells. Furthermore, transfection with miR-527 also inhibited the intrinsic expression of GPC-3 in the Huh-7 cell line. This indicated that miR-527 in the HCC tissues may be an important novel miRNA that targets the GPC-3 gene expression. GPC-3, whose expression is regulated by miR-527, may be involved in the development and progression of HCC.

Aspirin inhibits cholangiocarcinoma cell proliferation via cell cycle arrest in vitro and in vivo.

Cholangiocarcinoma is the most common biliary duct malignancy and the second most common primary liver cancer, accounting for 10­20% of hepatic malignancies. With high mortality and poor prognosis, the 5­year survival rate of cholangiocarcinoma is only 10%. A previous study demonstrated a significant association between aspirin use and a decreased risk of cholangiocarcinoma. However, the effect of aspirin on cholangiocarcinoma remains unknown. Therefore, the aim of the present study was to investigate the effects of aspirin on cholangiocarcinoma in vitro and in vivo. Three cholangiocarcinoma cell lines were used to analyze the effect of aspirin on cell proliferation, cell cycle progression, apoptosis, and the regulation of microRNAs. MicroRNAs are known to regulate the development and progression of various types of cancer. An HuCCT­1 xenograft model was used for the in vivo study. It was determined that aspirin inhibited the proliferation of human cholangiocarcinoma cells (except TKKK cells). Aspirin induced cell cycle arrest in the G0/G1 phase and regulated cell­cycle related proteins in cholangiocarcinoma cells (HuCCT­1 cells) but did not induce apoptosis. The expression of miR­340­5p was significantly upregulated after treatment, and overexpression of miR­340­5p inhibited the proliferation of HuCCT­1 cells and decreased the levels of cyclin D1. TKKK cells had low miR­340­5p expression, which may explain why aspirin had no effect on their proliferation. In vivo, aspirin reduced the growth of xenografted tumors. In conclusion, the present study indicated that aspirin partially inhibited cholangiocarcinoma cell proliferation and tumor growth by inducing G0/G1 phase cell cycle arrest, potentially through the miR­340­5p/cyclin D1 axis.