Retraction Notice to: Long Noncoding RNA OIP5-AS1 Promotes the Progression of Liver Hepatocellular Carcinoma via Regulating the hsa-miR-26a-3p/EPHA2 Axis.

[This retracts the article DOI: 10.1016/j.omtn.2020.05.032.].

Exosomal microRNA-15a from mesenchymal stem cells impedes hepatocellular carcinoma progression via downregulation of SALL4.

Hepatocellular carcinoma (HCC) is a heterogeneous tumor with an increased incidence worldwide accompanied by high mortality and dismal prognosis. Emerging evidence indicates that mesenchymal stem cells (MSCs)-derived exosomes possess protective effects against various human diseases by transporting microRNAs (miRNAs or miRs). We aimed to explore the role of exosomal miR-15a derived from MSCs and its related mechanisms in HCC. Exosomes were isolated from transduced MSCs and co-incubated with Hep3B and Huh7 cells. miR-15a expression was examined by RT-qPCR in HCC cells, MSCs, and secreted exosomes. CCK-8, transwell, and flow cytometry were used to detect the effects of miR-15a or spalt-like transcription factor 4 (SALL4) on cell proliferative, migrating, invasive, and apoptotic properties. A dual-luciferase reporter gene assay was performed to validate the predicted targeting relationship of miR-15a with SALL4. Finally, in vivo experiments in nude mice were implemented to assess the impact of exosome-delivered miR-15a on HCC. The exosomes from MSCs restrained HCC cell proliferative, migrating, and invasive potentials, and accelerated their apoptosis. miR-15a was expressed at low levels in HCC cells and could bind to SALL4, thus curtailing the proliferative, migrating, and invasive abilities of HCC cells. Exosomes successfully delivered miR-15a to HCC cells. Exosomal miR-15a depressed tumorigenicity and metastasis of HCC tumors in vivo. Overall, exosomal miR-15a from MSCs can downregulate SALL4 expression and thereby retard HCC development.

Whole-Transcriptome Sequencing Identifies Key Differentially Expressed mRNAs, miRNAs, lncRNAs, and circRNAs Associated with CHOL.

To systematically evaluate the whole-transcriptome sequencing data of cholangiocarcinoma (CHOL) to gain more insights into the transcriptomic landscape and molecular mechanism of this cancer, we performed whole-transcriptome sequencing based on the tumorous (C) and their corresponding non-tumorous adjacent to the tumors (CP) from eight CHOL patients. Subsequently, differential expression analysis was performed on the C and CP groups, followed by functional interaction prediction analysis to investigate gene-regulatory circuits in CHOL. In addition, The Cancer Genome Atlas (TCGA) for CHOL data was used to validate the results. In total, 2,895 differentially expressed messenger RNAs (dif-mRNAs), 56 differentially expressed microRNAs (dif-miRNAs), 151 differentially expressed long non-coding RNAs (dif-lncRNAs), and 110 differentially expressed circular RNAs (dif-circRNAs) were found in CHOL samples compared with controls. Enrichment analysis on those differentially expressed genes (DEGs) related to miRNA, lncRNA, and circRNA also identified the function of spliceosome. The downregulated hsa-miR-144-3p were significantly enriched in the competing endogenous RNA (ceRNA) complex network, which also included 7 upregulated and 13 downregulated circRNAs, 7 upregulated lncRNAs, and 90 upregulated and 40 downregulated mRNAs. Moreover, most of the DEGs and a few of the miRNAs (such as hsa-miR-144-3p) were successfully validated by TCGA data. The genes involved in RNA splicing and protein degradation processes and miR-144-3p may play fundamental roles in the pathogenesis of CHOL.

Prognosis for intrahepatic cholangiocarcinoma patients treated with postoperative adjuvant transcatheter hepatic artery chemoembolization.

OBJECTIVE: We used meta-analysis to evaluate the efficacy of transcatheter hepatic arterial chemoembolization (TACE) for the treatment of intrahepatic cholangiocarcinoma (ICC). METHODS: We performed the meta-analysis using the R 3.12 software and the quality evaluation of data using the Newcastle-Ottawa Scale. The main outcomes were recorded as 1-year overall survival (OS), 3-year OS, 5-year OS, and hazard ratio (HR) of TACE treatment or non-TACE treatment. The heterogeneity test was performed using the Q-test based on chi-square and I2 statistics. Egger's test was used to test the publication bias. The odds ratio or HR and 95% confidence interval (CI) were used to represent the effect index. RESULTS: Nine controlled clinical trials involving 1724 participants were included in this study; patients came mainly from China, Italy, South Korea, and Germany. In the OS meta-analysis, the 1-year and 3-year OS showed significant heterogeneity, but not the 5-year OS. TACE increased the 1-year OS (odds ratio = 2.66, 95% CI: 1.10-6.46) of the patients with ICC, but the 3- and 5-year OS rates were not significantly increased. The results had no publication bias, but the stability was weak. The HR had significant heterogeneity (I2 = 0%, P= 0.54). TACE significantly decreased the HR of ICC patients (HR = 0.59, 95% CI: 0.48-0.73). The results had no publication bias, and the stability was good. CONCLUSIONS: Treatment with TACE is effective for patients with ICC. Regular updating and further research and analysis still need to be carried out.

Long Noncoding RNA OIP5-AS1 Promotes the Progression of Liver Hepatocellular Carcinoma via Regulating the hsa-miR-26a-3p/EPHA2 Axis.

Numerous studies have suggested that dysregulated long noncoding RNAs (lncRNAs) contributed to the development and progression of many cancers. lncRNA OIP5 antisense RNA 1 (OIP5-AS1) has been reported to be increased in several cancers. However, the roles of OIP5-AS1 in liver hepatocellular carcinoma (LIHC) remain to be investigated. In this study, we demonstrated that OIP5-AS1 was upregulated in LIHC tissue specimens and its overexpression was associated with the poor survival of patients with LIHC. Furthermore, loss-of function experiments indicated that OIP5-AS1 promoted cell proliferation and inhibited cell apoptosis both in vitro and in vivo. Moreover, binding sites between OIP5-AS1 and hsa-miR-26a-3p as well as between hsa-miR-26a-3p and EPHA2 were confirmed by luciferase assays. Finally, a rescue assay was performed to prove the effect of the OIP5-AS1/hsa-miR-26a-3p/EPHA2 axis on LIHC cell biological behaviors. Based on all of the above findings, our results suggested that OIP5-AS1 promoted LIHC cell proliferation and invasion via regulating the hsa-miR-26a-3p/EPHA2 axis.

The apoptosis and GLP-1 hyposecretion induced by LPS via RIP/ROS/mTOR pathway in GLUTag cells.

Lipopolysaccharide (LPS) as a component of the outer structure of cell wall of gram-negative bacteria, could induce apoptosis in the intestinal endocrine cell line STC-1. However, the signaling cascades involved in this process have not been elucidated. Hence, we investigated the mechanism of cell apoptosis and hyposecretion of glucagon-like peptide 1 (GLP-1) induced by LPS in the GLUTag enteroendocrine cell line. LPS decreased the cell viability of GLUTag cells, up-regulated the TNF-α level, induced the apoptosis and down-regulated the mRNA and protein levels of GLP-1. In addition, TNF-α promoted LPS-induced apoptosis of GLUTag cells through mediating the formation of the RIP1/RIP3 necrosome. RIP1 and RIP3 knockdown increased cell viability, the mRNA and protein levels of GLP-1 and the mTOR signaling pathway-related proteins (p-mTOR and p-S6), and decreased the relative caspase 3/7 activity, cell apoptosis and ROS production. Further studies showed that ROS inhibited the mTOR signaling pathway. Moreover, the antioxidant N-acetyl-l-cysteine increased cell viability, GLP-1 expressions and the mTOR signaling pathway-related proteins, and inhibited the ROS production. However, the mTOR specific inhibitor (Rapa) reversed all these above effects. Taken together, our result revealed that LPS induced the apoptosis of GLUTag cells and GLP-1 hyposecretion through the RIP/ROS/mTOR pathway.

Influence of age on seven putative prostate tumor markers: a cohort study in Chinese men.

The accuracy and sensitivity of prostate-specific antigen (PSA) for prostate cancer diagnosis is often poor; however, the reasons for its inaccuracy have rarely been investigated, especially with respect to age. In this study, 476 healthy males, aged 10-89 years, were stratified into eight age groups, and levels of seven markers were determined: total PSA (tPSA), free PSA (fPSA), %fPSA, isoform [-2]proPSA (p2PSA), p2PSA/tPSA, %p2PSA, and the prostate health index (PHI). Both tPSA and fPSA levels increased with age. The tPSA level was highest (1.39 ng ml-1) at 70-79 years; %fPSA was highest (0.57 ng ml-1) at 10-19 years; and %p2PSA was lowest (18.33 ng ml-1) at 40-49 years. Both p2PSA and p2PSA/tPSA had relatively flat curves and showed no correlation with age (P = 0.222). PHI was a sensitive age-associated marker (P < 0.05), with two peaks and one trough. The coverage rates and radiance graphs of PHI and %p2PSA were more distinctive than those of tPSA and the other markers. In subjects older than 69 years, PHI and %p2PSA both began to decrease, approximately 10 years earlier than the decrease in tPSA. Our results suggest that the clinical diagnosis of prostate cancer using PSA should be investigated more comprehensively based on patient age. Moreover, %p2PSA and PHI could be considered as earlier markers that may be more suitable than PSA alone.

Knockdown of SALL4 inhibits the proliferation and reverses the resistance of MCF-7/ADR cells to doxorubicin hydrochloride.

BACKGROUND: Breast cancer is the most frequent malignancy in women and drug resistance is the major obstacle for its successful chemotherapy. In the present study, we analyzed the involvement of an oncofetal gene, sal-like 4 (SALL4), in the tumor proliferation and drug resistance of human breast cancer. RESULTS: Our study showed that SALL4 was up-regulated in the drug resistant breast cancer cell line, MCF-7/ADR, compared to the other five cell lines. We established the lentiviral system expressing short hairpin RNA to knockdown SALL4 in MCF-7/ADR cells. Down-regulation of SALL4 inhibited the proliferation of MCF-7/ADR cells and induced the G1 phase arrest in cell cycle, accompanied by an obvious reduction of the expression of cyclinD1 and CDK4. Besides, down-regulating SALL4 can re-sensitize MCF-7/ADR to doxorubicin hydrochloride (ADMh) and had potent synergy with ADMh in MCF-7/ADR cells. Depletion of SALL4 led to a decrease in IC50 for ADMh and an inhibitory effect on the ability to form colonies in MCF-7/ADR cells. With SALL4 knockdown, ADMh accumulation rate of MCF-7/ADR cells was increased, while the expression of BCRP and c-myc was significantly decreased. Furthermore, silencing SALL4 also suppressed the growth of the xenograft tumors and reversed their resistance to ADMh in vivo. CONCLUSION: SALL4 knockdown inhibits the growth of the drug resistant breast cancer due to cell cycle arrest and reverses tumor chemo-resistance through down-regulating the membrane transporter, BCPR. Thus, SALL4 has potential as a novel target for the treatment of breast cancer.

Effects of resistin on skeletal glucose metabolism.

Resistin is an adipokine highly related to insulin resistance (IR). The purpose of our research was to investigate how resistin influences skeletal glucose metabolism and explore its mechanisms. We constructed the recombinant plasmid pcDNA3.1 expressing resistin and then transfected it into C2C12 myocytes. The expression of resistin in C2C12 myocytes was detected by Western blotting. Glucose uptake was measured by 3H labeled glucose; glucose oxidation and glycogen synthesis was detected with 14C-labeled glucose. GLUT4 mRNA was measured by reverse transcription polymerase chain reaction (RT-PCR). We observed that resistin was expressed in transfected myocytes, and resistin decreased insulin induced glucose uptake rate by 28%-31% and inhibited the expression of GLUT4 mRNA. However, there was no significant difference in basal glucose uptake, and glucose oxidation and glycogen synthesis remained unchanged in all groups. It is concluded that resistin inhibits insulin induced glucose uptake in myocytes by downregulating the expression of GLUT4 and it has no effects on glucose oxidation and glycogen synthesis. Our findings may provide a clue to understand the roles of resistin in the pathogenesis of skeletal IR.

[The effects of glucose fluctuation on resistin].

OBJECTIVE: To explore the effect of glucose fluctuation on resistin. METHODS: The phorbol-12-myristate-13-acetate(PMA)-activated and differentiated U937 cells were exposed to experimental condition for 3 days, three groups of cells were formed, each one receiving the following fresh medium every 6 hours, respectively: (1) continuous 11.1 mmol/L glucose concentration medium (Con group), (2) continuous 22.2 mmol/L glucose concentration medium (CHG group), (3) alternating 11.1 mmol/L glucose concentration and 22.2 mmol/L glucose concentration medium every 6 hours (IHG group). The supernatants of cell median at the last 6 hours were collected to test resistin concentration. Besides, 92 subjects were selected and classified into three groups according to the results of oral glucose tolerance test: normal glucose tolerance group (NGT group, n=30), impaired glucose tolerance patients (IGT group, n=31) and newly diagnosed type 2 diabetes patients (T2DM group, n=31). Blood glucose and serum resistin levels were measured at 0 h and 1 h during oral glucose tolerance test (OGTT) to compare the glucose fluctuation (ΔGlu1-0) and the change of serum resistin level (ΔlnRes1-0) among the three groups. RESULTS: Resistin concentration in the Con, CHG and IHG group was (73.62±5.07) ng/L, (97.78±7.00) ng/L and (212.49±28.81) ng/L respectively and in IHG group it was higher as compared with the other two groups (P<0.05). ΔGlu1-0 in NGT, IGT and T2DM group was (2.31±2.30) mmol/L, (5.70±2.08) mmol/L and (8.41±2.63) mmol/L respectively; ΔGlu1-0 increased gradually in all the three groups (P<0.05). Serum resistin level from 0 h to 1 h in the NGT group was 6.41 (1.52-15.76) µg/L to 6.96 (1.52-22.70) µg/L, in the IGT group 5.47 (1.49-24.09) µg/L to 9.12 (1.27-21.94) µg/L and in the T2DM group 5.77 (1.11-30.10) µg/L to 9.27(1.02-48.15) µg/L. In the IGT and T2DM group serum resistin level increased from 0 h to 1 h (P<0.05), but no difference was observed in the NGT group (P>0.05). ΔlnRes1-0 in these 3 groups was (0.05±0.05) µg/L, (0.25±0.04) µg/L and (0.37±0.03) µg/L respectively and the change in the T2DM group was significant as compared with that in the NGT group, ΔlnRes1-0 was positively correlated with ΔGlu1-0 (r=0.23, P=0.02). CONCLUSION: Glucose fluctuation induced monocyte/macrophage to secrete resistin, greater the glucose fluctuation, greater the change of amplitude of serum resistin.

Effects of resistin expression on glucose metabolism and hepatic insulin resistance.

In order to observe the effect of increased serum resistin on glucose metabolism, insulin sensitivity, and hepatic insulin resistance (IR), mice were intravenously injected with recombinant adenovirus carrying the resistin gene (Adv-resistin-EGFP). Changes in hepatic glucose metabolism were observed using the Periodic Acid-Schiff method. Hepatic AMP-activated protein kinase (AMPK) activation was assessed by Western blot analysis, and glucose-6-phosphatase (G6Pase) and phosphoenolpyruvate carboxykinase (PEPCK) mRNA expression was determined using real-time RT-PCR. Although no effect on fasting blood glucose was detected, increased fasting insulin levels, decreased glucose tolerance and insulin sensitivity, and reduced hepatic glycogen levels and AMPK activation were seen in the Adv-resistin-EGFP mice. Finally, elevated G6Pase and PEPCK mRNA expression levels were detected upon overexpression of resistin. Resistin may inhibit hepatic AMPK activity, which results in elevated expression of gluconeogenic enzymes thereby affecting glucose metabolism and leading to decreased glycogen storage that contributes to the development of hepatic IR.