Mesenchymal stem cell-originated exosomal circDIDO1 suppresses hepatic stellate cell activation by miR-141-3p/PTEN/AKT pathway in human liver fibrosis.

Liver fibrosis is a common pathologic stage of the development of liver failure. It has showed that exosomes loaded with therapeutic circRNAs can be manufactured in bulk by exosome secreted cells in vitro, thus enabling personalized treatment. This study aimed to investigate the role of exosome-based delivery of circDIDO1 in liver fibrosis. Levels of genes and proteins were examined by qRT-PCR and Western blot. Cell proliferation, apoptosis, and cell cycle were analyzed by using cell counting kit-8 (CCK-8) assay, EdU assay, and flow cytometry, respectively. The binding between circDIDO1 and miR-141-3p was confirmed by dual-luciferase reporter, RNA pull-down and RIP assays. Exosomes were isolated by ultracentrifugation, and qualified by transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA) and Western blot. CircDIDO1 overexpression or miR-141-3p inhibition suppressed the proliferation, reduced pro-fibrotic markers, and induced apoptosis as well as cell cycle arrest in hepatic stellate cells (HSCs) by blocking PTEN/AKT pathway. Mechanistically, circDIDO1 acted as an endogenous sponge for miR-141-3p, further rescue experiments showed that circDIDO1 suppressed HSC activation by targeting miR-141-3p. Extracellular circDIDO1 could be incorporated into exosomes isolated from mesenchymal stem cells (MSCs), and transmitted to HSCs to restrain HSC activation. Clinically, low levels of serum circDIDO1 in exosome were correlated with liver failure, and serum exosomal circDIDO1 had a well diagnostic value for liver fibrosis in liver failure patients. Transfer of circDIDO1 mediated by MSC-isolated exosomes suppressed HSC activation through the miR-141-3p/PTEN/AKT pathway, gaining a new insight into the prevention of liver fibrosis in liver failure patients.

Effect of liver steatosis on liver stiffness measurement in chronic hepatitis B patients with normal serum alanine aminotransferase levels: A multicentre cohort study.

Liver steatosis is becoming increasingly common in patients with chronic hepatitis B (CHB), and its effect on liver stiffness measurement (LSM), as assessed by transient elastography, remains controversial. Seven hundred and fifty-five patients with CHB and normal serum alanine aminotransferase levels, who underwent vibration-controlled transient elastography and liver biopsy, were included in the study. We examined whether the histological degree of liver steatosis affects the accuracy of transient elastography-assessed LSM in these patients. Among the 755 CHB patients included in the study, 286 (37.9%) had liver steatosis, of whom 156 had grade S1, 74 had grade S2, and 56 had grade S3 on histology. Presence of liver steatosis was independently associated with greater body mass index (BMI, adjusted-odds ratio [OR] = 5.786, 95% CI: 3.998-8.373, p = 0.018), and higher serum total cholesterol (adjusted-OR = 7.944, 95% CI: 4.731-13.339, p < 0.001) and triglyceride levels (adjusted-OR = 2.777, 95% CI: 2.050-3.761, p < 0.001). There was no significant association between liver steatosis and fibrosis stage (OR = 1.016, 95% CI: 0.905-1.140, p = 0.790). Age (B-coefficient = 0.020, 95% CI: 0.001-0.040, p = 0.044), BMI (B-coefficient = 0.060, 95% CI: 0.011-0.127, p = 0.019), serum gamma-glutamyl-transpeptidase (GGT, B-coefficient = 0.015, 95% CI: 0.001-0.029, p = 0.032), positivity for HBeAg (B-coefficient = -0.816, 95% CI: -1.568 to -0.064, p = 0.034), as well as liver fibrosis stage (B-coefficient = 2.796, 95% CI: 2.501-3.090, p < 0.001), and inflammation activity grade (B-coefficient = 0.648, 95% CI: 0.162-1.135, p = 0.009) were all independently associated with higher LSM, while no significant association was found between degree of liver steatosis and LSM. Among patients with the same histological fibrosis stage, LSM values did not show any significant difference among patients with absent, mild, moderate or severe steatosis. We conclude that liver steatosis has no significant effect on transient elastography-measured LSM in CHB patients with normal serum alanine aminotransferase levels.

circNFIX facilitates hepatocellular carcinoma progression by targeting miR-3064-5p/HMGA2 to enhance glutaminolysis.

Hepatocellular carcinoma (HCC) is acknowledged to be a fatal malignant cancer around the world. Circular RNAs (circRNAs) function as crucial regulators in the pathological procession of HCC. Here, we elucidated the biological function of a novel circRNA, circNFIX, in HCC tumorigenesis. qRT-PCR was performed to determine the expressions of circNFIX, miR-3064-5p, and HMGA2. circNFIX stability was evaluated after treatment with ribonuclease R. The growth and invasion of HCC cells were assessed by CCK8 and transwell assays. Protein levels were measured by Western blotting. The levels of glutaminolysis metabolites were evaluated by commercial kits. Dual-luciferase report assay, RNA immunoprecipitation (RIP) assay and RNA pull-down assay were performed for validating the interaction between miR-3064-5p and circNFIX/HMGA2. Tumor growth in vivo was detected using xenograft assay. Our results showed that circNFIX was remarkably up-regulated in HCC and was associated with a poor survival. Knockdown of circNFIX repressed proliferation, invasion and glutaminolysis of HCC cells. Moreover, circNFIX directly sponged miR-3064-5p to release HMGA2 expression, and thus conferred the malignant development of HCC. In conclusion, circNFIX serves as a competing endogenous RNA to accelerate HCC progression via regulating miR-3064-5p/HMGA2 axis, suggesting a therapeutic strategy for HCC intervention.

Silenced lncRNA DDX11-AS1 or up-regulated microRNA-34a-3p inhibits malignant phenotypes of hepatocellular carcinoma cells via suppression of TRAF5.

BACKGROUND: Studies have discussed long noncoding RNA DDX11-AS1 (DDX11-AS1)-mediated downstream mechanism in hepatocellular carcinoma (HCC). The goal of this study was to investigate the regulatory mechanism of DDX11-AS1-mediated microRNA-34a-3p (miR-34a-3p)/tumor necrosis factor receptor-associated factor 5 (TRAF5) axis on HCC cells. METHODS: DDX11-AS1, miR-34a-3p and TRAF5 expression levels in HCC were detected. The correlation of DDX11-AS1, miR-34a-3p and TRAF5 in HCC patients was analyzed by Pearson test. HCC cells were transfected with corresponding plasmid/oligonucleotide, and cell proliferation, migration, invasion, apoptosis and tumor formation ability were detected. Bioinformatics software, dual luciferase report experiment and RNA-pull down experiment analysis were applied to verify the targeting relationship between DDX11-AS1, miR-34a-3p and TRAF5. RESULTS: Elevated DDX11-AS1 and TRAF5 and reduced miR-34a-3p exhibited in HCC. Silenced DDX11-AS1 or up-regulated miR-34a-3p inhibited the proliferation, migration, invasion, promoted apoptosis of HCC cells and repressed the tumor growth in nude mice. In addition, DDX11-AS1 bound to miR-34a-3p to target TRAF5. Silencing TRAF5 or elevating miR-34a-3p expression mitigated up-regulated DDX11-AS1-mediated promotion of tumor growth. CONCLUSION: Silenced DDX11-AS1 or up-regulated miR-34a-3p inhibits HCC cell growth via elevation of TRAF5, which could be of great benefit to find early diagnostic markers for HCC patients.

MiR-15b and miR-16 suppress TGF-ß1-induced proliferation and fibrogenesis by regulating LOXL1 in hepatic stellate cells.

Activation of hepatic stellate cells (HSCs) is an important event during the progress of liver fibrosis. MicroRNA (miR)-15b and miR-16 have been found to be involved in activation of HSCs. However, the roles of miR-15b/16 in liver fibrosis remain unclear. The expression of miR-15b/16 was decreased in TGF-ß1-stimulated LX-2 cells. Overexpression of miR-15b/16 in LX-2 cells suppressed TGF-ß1-induced cell proliferation and the expression levels of tissue inhibitor of metalloproteinase type 1, collagen type I, and α-smooth muscle actin. The activation of Smad2/3 caused by TGF-ß1 was repressed by miR-15b/16 overexpression. The two miRNAs directly bound to the 3'-UTR of lysyl oxidase-like 1 (LOXL1) and suppressed the LOXL1 expression. Furthermore, knockdown of LOXL1 attenuated miR-15b/16 downregulation-induced cell proliferation, fibrogenic response and phosphorylation of Smad2/3. Collectively, miR-15b/16 exhibited anti-fibrotic activity through regulation of Smad2/3 pathway.

MicroRNA-9 enhances sensitivity to cetuximab in epithelial phenotype hepatocellular carcinoma cells through regulation of the eukaryotic translation initiation factor 5A-2.

Hepatocellular carcinoma (HCC) is one of the most widespread malignant human tumors worldwide. Treatment options include radiotherapy, surgical intervention and chemotherapy; however, drug resistance is an ongoing treatment concern. In the present study, the effects of a microRNA (miR/miRNA), miR-9, on the sensitivity of HCC cell lines to the epidermal growth factor receptor inhibitor, cetuximab, were examined. miR-9 has been proposed to serve a role in tumorigenesis and tumor progression. In the present study, bioinformatics analyses identified the eukaryotic translation initiation factor 5A2 (eIF-5A-2) as a target of miR-9. The expression levels of miR-9 and eIF-5A-2 were examined by reverse transcription-quantitative polymerase chain reaction and HCC cell lines were transfected with miR-9 mimics and inhibitors to determine the effects of the miRNA on cell proliferation and viability. The miR-9 mimic was revealed to significantly increase the sensitivity of epithelial phenotype HCC cells (Hep3B and Huh7) to cetuximab, while the miR-9 inhibitor triggered the opposite effect. There were no significant differences in sensitivity to cetuximab observed in mesenchymal phenotype HCC cells (SNU387 and SNU449). Cells lines displaying high expression levels of eIF-5A-2 were more resistant to cetuximab. Transfection of cells with a miR-9 mimic resulted in downregulation of the expression of eIF-5A-2 mRNA, while an miR-9 inhibitor increased expression. When expression of eIF-5A-2 was knocked down with siRNA, the effects of miR-9 on cetuximab sensitivity were no longer observed. Taken together, these data support a role for miR-9 in enhancing the sensitivity of epithelial phenotype HCC cells to cetuximab through regulation of eIF-5A-2.

eIF5A2 is an alternative pathway for cell proliferation in cetuximab-treated epithelial hepatocellular carcinoma.

Heaptocellular carcinoma (HCC) is still a great health problem around the world. Recently, the cetuximab has been implicated to have therapeutic values for HCC. However, cetuximab-resistance has also been synchronously reported pertaining to HCC treatment. This study aimed to evaluate the role of eIF5A2 in cetuximab-treated HCC cell proliferation, and whether eIF5A2 specific inhibitor GC7 has any effects on cetuximab-mediated proliferation inhibition in HCC cell lines. It was observed that GC7 significantly inhibited cell proliferation in HCC cell lines. GC7 synergized cetuximab to inhibit the proliferation in epithelial HCC cell lines HepG2, Huh7 and Hep3B, but not in mesenchymal cell lines SNU387 and SNU449. Knockdown of eIF5A-2 by specific siRNA exhibited the similar effects as GC7 did. In cetuximab-treated cells, cetuximab decreased the protein level of EGFR and phosphorylated STAT3 and unexpectedly up-regulated the expression level of eIF5A2, indicating the activation of eIF5A2 pathway. In turn, cetuximab also synergized GC7 to inhibit cell proliferation in epithelial cell lines. GC7 also suppressed hypoxia-induced cell proliferation in epithelial cell lines. These data suggest that eIF5A2 is an alternative pathway for cell proliferation in epithelial HCC cells escaping from the cytotoxicity of cetuximab. The eIF5A inhibitor GC7 might be a potent agent that promotes the cytotoxicity of cetuximab on epithelial HCC cells.

Let-7a enhances the sensitivity of hepatocellular carcinoma cells to cetuximab by regulating STAT3 expression.

BACKGROUND: Let-7 miRNAs are reported to play an inhibitory role in carcinogenesis, tumor progression, recurrence, and pluripotency of cancer. However, few studies have reported the relationship between let-7 and drug sensitivity, especially for let-7a (a subtype of let-7). This study aimed to investigate the function of let-7a in regulating the sensitivity of hepatocellular carcinoma (HCC) cell lines to cetuximab. METHODS: The cytotoxicity of cetuximab on HCC cell lines (Huh7, Hep3B, HepG2, SNU449, and SNU387) was evaluated using a cell viability assay (the Cell Counting Kit-8 assay) and a cell proliferation assay (the Click-iT EdU Imaging Kit) in the presence of a control, a let-7a mimic, and a let-7a inhibitor. Small interfering RNA to knockdown the expression of signal transducer and activator of transcription 3 (STAT3) were employed. Protein and mRNA expression levels were determined using quantitative polymerase chain reaction and Western blot analysis. RESULTS: It was found that let-7a enhances the sensitivity of HCC cells with an epithelial phenotype (Huh7, Hep3B, and HepG2) to cetuximab, but has no effect on cells with the mesenchymal phenotype (SNU449 and SNU387). It was determined that STAT3 was a target mRNA of let-7a using TargetScan. Expression of STAT3 and let-7a mRNA were negatively correlated in HCC cell lines. Moreover, let-7a altered the protein and mRNA expression of STAT3. Furthermore, STAT3 knockdown enhanced the function of cetuximab on HCC cell lines with epithelial phenotypes, but not on HCC cell lines with mesenchymal phenotypes. Finally, a rescue experiment confirmed that let-7a affected the sensitivity of HCC cell lines to cetuximab by interacting with STAT3. CONCLUSIONS: There is a functional link between let-7a and STAT3 in enhancing the sensitivity of HCC cells with an epithelial phenotype to cetuximab. Our results provide novel insight into new methodologies for combating HCC drug resistance.

Triptolide synergistically enhances antitumor activity of oxaliplatin in colon carcinoma in vitro and in vivo.

Triptolide (TPL) is a major active component isolated from the natural herb Tripteryglum wilfordii Hook. F. It has proved to possess a variety of pharmacological effects including anti-inflammatory and antitumor activities. The aim of the present study is to explore the efficiency of combination therapy with TPL and oxaliplatin (OXA) and identify the in vitro and in vivo cytotoxicity on colon cancer lines and mice model. Cell viability was measured by MTT assay and cell apoptosis rate was analyzed by FACS assay after treatment with TPL and OXA alone, and TPL combined with OXA in colon cancer cell line SW480. The results demonstrated that combination therapy of TPL and OXA could effectively inhibit the proliferation of colon cancer cell line SW480 and induce cell apoptosis of colon cancer cells. It was partly induced by inhibiting nuclear translocation of ß-catenin and the expression of the target genes in cell cycle, which was detected by western blotting and real-time PCR. Moreover, in nude mice model, tumor growth was significantly suppressed in the group treated with TPL in combination with OXA. There was no obvious cytotoxity in mice analyzed by normal blood test and liver and kidney toxicity test. In conclusion, our result revealed that the combination therapy with TPL and OXA exerted synergistic antitumor effects at low concentration in colon cancer cells, with less cytotoxity, which exhibited high potency for clinical applications.