ATP citrate lyase promotes the progression of hepatocellular carcinoma by activating the REGγ-proteasome pathway.

The search for novel tumor biomarkers and targets is of significant importance for the early clinical diagnosis and treatment of Hepatocellular Carcinoma (HCC). The mechanisms by which ATP citrate lyase (ACLY) promotes HCC progression remain unclear, and the connection between ACLY and REGγ has not been reported in the literature. In vitro, we will perform overexpression/knockdown of ACLY or overexpression/knockdown of REGγ to investigate the impact of ACLY on HCC cells and its underlying mechanisms. In vivo, we will establish mouse tumor models with overexpression/knockdown of ACLY or overexpression/knockdown of REGγ to study the effect of ACLY on mouse tumors and its mechanisms. Firstly, ACLY overexpression upregulated REGγ expression and activated the REGγ-proteasome pathway, leading to changes in the expression of downstream signaling pathway proteins. This promoted HCC cell proliferation, invasion, and migration in vitro, as well as tumor growth and metastasis in vivo. Secondly, ACLY overexpression increased acetyl-CoA production, upregulated the acetylation level of the REGγ promoter region histone H3K27ac, and subsequently induced REGγ expression. Lastly, enhanced acetylation of the REGγ promoter region histone H3K27ac resulted in upregulated REGγ expression, activation of the REGγ-proteasome pathway, changes in downstream signaling pathway protein expression, and promotion of HCC cell proliferation, invasion, and migration in vitro, as well as tumor growth and metastasis in vivo. Conversely, REGγ knockdown reversed these effects. ACLY and REGγ may serve as potential biomarkers and clinical therapeutic targets for HCC.

Liensinine inhibits progression of intrahepatic cholangiocarcinoma by regulating TGF-ß1 /P-smad3 signaling through HIF-1a.

Intrahepatic cholangiocarcinoma (ICC) is a high-grade malignant digestive system tumor with an insidious onset and unfavorable prognosis. Liensinine, a small molecule derived from plants, has been proven to have significant tumor suppressor activity in other cancers. However, there are no reports on whether liensinine can inhibit the proliferation or metastasis of ICC. This study aimed to explore the tumor-suppressive activity of liensinine in ICC and its underlying mechanisms. The phenotypic changes in ICC cells were monitored in vitro using cell function tests. Western blot and immunofluorescence analyses verified the efficacy of liensinine. Tumor-bearing nude mice were used to explore the effect of liensinine on tumors and its toxicity and side effects in vivo. Liensinine suppressed ICC cell proliferation and arrested the cell cycle at the G1 phase. The epithelial-mesenchymal transition (EMT) of ICC cells was also inhibited, thereby restraining their invasion and migration of tumor cells. In addition, this study found that the potential mechanism of liensinine inhibiting EMT may be via suppression of the TGF-ß1/P-smad3 signaling pathway through hypoxia-inducible factor 1 alpha (HIF-1a). In vivo experiments showed that liensinine inhibited the growth of Hucc-T1 transplanted tumors in nude mice. Liensinine restrained the proliferation of ICC cells and suppressed EMT in ICC via the HIF-1a-mediated TGF-ß1/P-smad3 signaling pathway.

ATP citrate lyase inhibitor triggers endoplasmic reticulum stress to induce hepatocellular carcinoma cell apoptosis via p-eIF2α/ATF4/CHOP axis.

ATP citrate lyase (ACLY), a key enzyme in the metabolic reprogramming of many cancers, is widely expressed in various mammalian tissues. This study aimed to evaluate the effects and mechanisms of ACLY and its inhibitor BMS-303141 on hepatocellular carcinoma (HCC). In this study, ACLY was highly expressed in HCC tissues, especially in HepG2 and Huh7 cells, but was down-regulated in Hep3B and HCC-LM3 cells. Besides, ACLY knockdown inhibited HepG2 proliferation and clone formation, while opposite result was noticed in HCC-LM3 cells with ACLY overexpression. Moreover, ACLY knockdown impeded the migration and invasion abilities of HepG2 cells. Similarly, BMS-303141 suppressed HepG2 and Huh-7 cell proliferation. The p-eIF2α, ATF4, CHOP p-IRE1α, sXBP1 and p-PERK were activated in HepG2 cells stimulated by BMS-303141. In cells where ER stress was induced, ATF4 was involved in BMS-303141-mediated cell death procession, and ATF4 knockdown reduced HCC cell apoptosis stimulated by BMS-303141. In a mouse xenograft model, combined treatment with BMS-303141 and sorafenib reduced HepG2 tumour volume and weight. In addition, ACLY expression was associated with HCC metastasis and tumour-node-metastases staging. Survival analysis and Cox proportional hazards regression model showed that overall survival was lower in HCC patients with high ACLY expression; AFP level, TNM staging, tumour size and ACLY expression level were independent risk factors affecting their overall survival. In conclusion, ACLY might represent a promising target in which BMS-303141 could induce ER stress and activate p-eIF2α/ATF4/CHOP axis to promote apoptosis of HCC cells, and synergized with sorafenib to enhance the efficacy of HCC treatment.

LncRNA H19/miR-194/PFTK1 axis modulates the cell proliferation and migration of pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) remains a huge challenge due to its high mortality and morbidity; gene therapy might be a promising treatment for PDAC. The critical role of Wnt-signaling pathway in cancer pathogenesis has been widely recognized; cyclin-dependent kinase 14 (CDK14, PFTK1)-induced low-density lipoprotein receptor-related proteins 5/6 (LRP5/6) phosphorylation is an important issue in Wnt-signaling activation. Long noncoding RNA (LncRNA)-microRNA (miRNA)-messenger RNA (mRNA) modulating the pathogenesis of cancers has been regarded as a major mechanism. In the current study, upregulated lncRNAs positively correlated with PFTK1 were analyzed and selected using The Cancer Genome Atlas (TCGA) database. Of them, lncRNA H19 can activate Wnt signaling in cancers. In PDAC tissues, the expression of H19 and PFTK1 were upregulated; H19 knockdown suppressed the cell proliferation and migration of PDAC, while PFTK1 overexpression partially attenuated the suppressive effect of H19 knockdown. As analyzed by TCGA and predicted by online tools, miR-194 was negatively correlated with PFTK1 and might bind to both H19 and PFTK1, which was further confirmed by luciferase reporter and RNA immunoprecipitation assays. Moreover, the effect of H19 knockdown on PFTK1 protein and the cell proliferation and migration could be partially reversed by miR-194 inhibition; H19/miR-194 axis modulated PDAC cell proliferation and migration through PFTK1 downstream Wnt signaling. Results suggested that rescuing miR-194 expression in PDAC can inhibit lncRNA H19 and PFTK1 expression, subsequently suppressing PDAC cell proliferation and migration. Due to the complexity of the lncRNA-miRNA-mRNA network, further in vivo experiments examining potential side effects are needed in future study to explore the clinical application of these findings.

Inhibitory effects of capsaicin on hepatic stellate cells and liver fibrosis.

Hepatic stellate cells (HSCs) play an important role in the process of liver fibrosis. In this study, we investigated the inhibitory effects of capsaicin on HSCs and liver fibrosis. Cultured HSCs were incubated with various concentrations of capsaicin. Cell proliferation was examined using a cell counting kit. Production of hydrogen peroxide was determined using a 2',7'-dichlorofluorescin diacetate (DCFH-DA) assay. The mRNA and protein expression of target genes was analyzed by reverse transcription PCR and Western blot analysis, respectively. Cell apoptosis was evaluated by annexin V-FITC and propidium iodide (PI) costaining followed by flow cytometric analysis. A CCl4 rat liver fibrosis model was used to assess in vivo effects of capsaicin by histological examination and measurement of liver fibrosis markers, including hydroxyproline content, serum type III collagen, and hyaluronic acid (HA) levels. Our results show that capsaicin dose-dependently inhibited cell proliferation, suppressed cell activation, and decreased hydrogen peroxide production in cultured HSCs. Capsaicin reduced the mRNA levels of tissue inhibitors of metalloproteinase 1 (TIMP-1) and transforming growth factor-ß1 (TGF-ß1) in HSCs. Moreover, capsaicin-induced cell apoptosis was associated with increased expression of Bax, cytochrome c (cyt c), and caspase-3, but reduced levels of Bcl-2. The animal studies further revealed that capsaicin efficiently reduced the extent of liver fibrosis, inhibited HSC proliferation, and promoted cell apoptosis. Our findings suggest that capsaicin might inhibit fibrogenesis by inhibiting the activities of HSCs.

[Regulation effect of adipose-derived mesenchymal stem cells on pancreatic cancer cells].

OBJECTIVE: To analyze the effects of adipose tissue-derived stem cells (ADSCs) on the proliferation and invasion of pancreatic cancer (PaCa) cells and the the possible mechanism involved. METHODS: ADSCs were isolated and co-cultured with PaCa cells. CCK-8 assay was used to detect the proliferation of PaCa cells. An ELISA was used to determine the concentration of stromal cell-derived factor-1 (SDF-1) in the supernatants. The proliferation of PaCa cells by SDF-1 was measured. AMD3100 regulated the co-culture of ADSCs and PaCa. The tumor growth of PaCa cells was assessed after treatment by ADSCs in vivo. RESULTS: ADSCs can promote the proliferation and invasion of PaCa cells (proliferation: SW1990: 1.535 ± 0.153; PANC-1: 1.370 ± 0.100; the value of control was 1; invasion: SW1990: 47.0 ± 2.6 vs. 28.3 ± 1.3; PANC-1: 40.3 ± 1.8 vs. 24.3 ± 1.3; t = 4.332-9.558, P < 0.05). The expression of SDF-1 was high in ADSCs, but not in PaCa cells (69 ± 5 vs. 0 and 0, F = 389.134, P < 0.01). The promotion of SDF-1 on PaCa cells depends on the concentration. AMD3100 significantly downregulates these growth-promoting effects of ADSCs on PaCa cells. ADSCs significantly promoted the growth of SW1990 in nude mice at the 5(th) week (volume: (1295 ± 102) mm(3) vs. (967 ± 81) mm(3), t = 5.614, P < 0.05) , but not in PANC-1 cell. CONCLUSION: ADSCs can promote the proliferation and invasion of PaCa cells, which may involve the SDF-1/CXCR4 axis.

A novel five-lncRNA signature panel improves high-risk survival prediction in patients with cholangiocarcinoma.

Cholangiocarcinoma (CCA) is a fatal disease with dismal survival rates. Long non-coding RNA (lncRNA) expression profiling as potential prognostic biomarkers play critical roles in tumor initiation, development, and poor prognosis. Identifying specific lncRNA to predict the prognosis of CCA patients in the early stages is very important for improving a patient's survival. In the current study, we aimed to establish a novel risk-stratification lncRNA signature panel in CCA. The initial lncRNA discovery was identified in The Cancer Genome Atlas database (TCGA cohort). The Cox regression analysis was used to establish the lncRNA prognostic model and the receiver operating characteristic (ROC) curve analysis was performed to assess the specificity and sensitivity of the model. This was followed by independent validation of the lncRNA signature in the CCA patients from the First Affiliated Hospital of Wenzhou Medical University (WMU cohort). Furthermore, by using the Gene Ontology function and Kyoto Encyclopedia Gene and Genome pathway enrichment analysis, we explored the potential function of prognosis lncRNA. Finally, five lncRNA (HULC; AL359715.5; AC006504.8; AC090114.2; AP00943.4) were screened to establish the predictive model that significantly associated with poor overall survival(HR:4.879;95%CI,1.587-14.996;p=0.006). This five-lncRNA signature model showed excellent accuracy in the TCGA cohort (AUC=0.938), and also robustly predicted survival in the validation WMU cohort(AUC=0.816). Functional enrichment analysis suggested prognostic lncRNA was primarily associated with CCA-related biological processes. Our data established a novel lncRNA signature model for CCA risk-stratification and robust identification of CCA patients with poor molecular genotypes. Moreover, it revealed new molecular mechanisms of CCA.

Plasmalemma vesicle-associated protein promotes angiogenesis in cholangiocarcinoma via the DKK1/CKAP4/PI3K signaling pathway.

Cholangiocarcinoma (CCA) is aggressive and has poor clinical outcomes because of typically delayed diagnosis and a lack of effective non-surgical therapeutic options. Recent studies have shown that plasmalemma vesicle-associated protein (PLVAP) is related to angiogenesis in various tumors, and in vivo PLVAP targeting therapy has been proven effective against hepatocellular carcinoma and pancreatic cancer. The goal of this study was to determine the potential therapeutic utility of targeting PLVAP and thus angiogenesis in CCA and explore the underlying molecular mechanisms. We found that the PLVAP expression levels were significantly higher in CCA tissues when compared with matched adjacent non-tumor tissues obtained from a total of 90 CCA patients; higher expression levels of PLVAP were associated with shorter overall survival of patients. In addition, overexpression of PLVAP was associated with higher micro-vessel density in CCA tissues. In a PLVAP overexpressing CCA patient-derived xenograft model, a novel humanized anti-PLVAP antibody in combination with Gemcitabine plus Cisplatin was significantly inhibited tumor growth. Molecular analysis of CCA cells co-cultured with human umbilical vascular endothelial cells or human hepatic sinusoidal endothelial cells showed that Dickkopf-related protein 1 (DKK1) secreted by CCA cells activated the PI3K/Akt pathway after binding to its receptor, cytoskeleton-associated protein 4 (CKAP4), resulting in the upregulation of PLVAP. Thus, CCA cells increased the angiogenic potency of endothelial cells in a paracrine fashion. Consistently, patients bearing CKAP4 and PLVAP overexpressing tumors had a poor prognosis. In conclusion, the DKK1/CKAP4/PI3K/PLVAP pathway increases angiogenesis in CCA and is therefore a potential anti-angiogenic target.

A positive feedback loop between Periostin and TGFß1 induces and maintains the stemness of hepatocellular carcinoma cells via AP-2α activation.

BACKGROUND: Liver cancer stem cells (LCSCs) play key roles in the metastasis, recurrence, and chemotherapeutic resistance of hepatocellular carcinoma (HCC). Our previous research showed that the POSTN gene is closely related to the malignant progression and poor prognosis of HCC. This study aimed to elucidate the role of POSTN in generating LCSCs and maintaining their stemness as well as the underlying mechanisms. METHODS: Human HCC tissues and matched adjacent normal tissues were obtained from 110 patients. Immunohistochemistry, western blotting (WB), and RT-PCR were performed to detect the expression of POSTN and stemness factors. The roles of transforming growth factor (TGF)-ß1 and AP-2α in the POSTN-induced stemness transformation of HCC cells were explored in vitro and in vivo using LCSCs obtained by CD133+ cell sorting. RESULTS: The high expression of POSTN was correlated with the expression of various stemness factors, particularly CD133, in our HCC patient cohort and in TCGA and ICGC datasets. Knockdown of POSTN expression decreased the abilities of HCC cell lines to form tumours in xenograft mouse models. Knockdown of POSTN expression also suppressed cell viability and clone formation, invasion, and sphere formation abilities in vitro. Knockdown of AP-2α attenuated the generation of CD133+ LCSCs and their malignant behaviours, indicating that AP-2α was a critical factor that mediated the POSTN-induced stemness transformation and maintenance of HCC cells. The role of AP-2α was verified by using a specific αvß3 antagonist, cilengitide, in vitro and in vivo. Activation of POSTN could release TGFß1 from the extracellular matrix and initiated POSTN/TGFß1 positive feedback signalling. Furthermore, we found that the combined use of cilengitide and lenvatinib suppressed the growth of HCC cells with high POSTN expression more effectively than the use of lenvatinib alone in the patient-derived xenograft (PDX) mouse model. CONCLUSIONS: The POSTN/TGFß1 positive feedback pathway regulates the expression of stemness factors and the malignant progression of HCC cells by regulating the transcriptional activation of AP-2α. This pathway may serve as a new target for targeted gene therapy in HCC.

The effect of splenic arterial blood flow (SBF) on severity of hypersplenism and analysis of factors associated with SBF.

BACKGROUND: This study aims to explore the relationship between spleen arterial blood flow (SBF) with platelet count, spleen index (SPI) and the serum nitric oxide (NO) level of patients with liver cirrhosis and to investigate the role of SBF in the development of hypersplenism. METHODOLOGY: Platelet count, SPI, SBF and serum NO levels were evaluated in 100 patients with liver cirrhosis caused by hepatitis B with hypersplenism (cirrhosis group) and 30 healthy persons without hypersplenism (control group). RESULTS: Platelet count in cirrhosis group and control group was 57.0 +/- 25.6 x 109/L and 205.8 +/- 47.4 x 109/L (p = 0.000), SBF was 535.7 +/- 263.7 milmin and 172.2 +/- 66.9 ml/min (p = 0.000), and serum NO level was 98.51 +/- 23.06 micromol/L and 48.43 +/- 19.47 micromol/L (p = 0.000). Linear correlations were made between SBF and platelet count in cirrhosis group (r = -0.573, p = 0.000), SBF and SPI (r = 0.607, p = 0.01), SBF and serum NO level (r = 0.754, p = 0.000). Moreover, serum NO level increased as liver disease aggravated (82.50 +/- 15.04 pmol/L in Child grade A, 94.61 +/- 21.00 micromol/L in grade B and 116.83 +/- 18.03 micromol/L in grade C; grade A versus grade C, p = 0.003). CONCLUSION: The elevation of SBF may play an important role in the development of hypersplenism and disorders in vasoactive factors such as the serum NO caused by liver cirrhosis may play an important role in the elevation of SBF.

hsa_circ_102559 Acts as the Sponge of miR-130a-5p to Promote Hepatocellular Carcinoma Progression Through Regulation of ANXA2.

Circular RNAs (circRNAs) are critical regulators in tumor initiation and development and participate in the pathological process of hepatocellular carcinoma (HCC). However, the specific role and mechanism of circRNA, hsa_circ_102559, in HCC remains elusive. First, analysis of HCC-related circRNA expression profile GSE97332 and HCC patients showed a significant upregulation of hsa_circ_102559 in HCC tissues. Upregulation of hsa_circ_102559 in HCC cells was associated with the metastatic properties. Second, hsa_circ_102559 significantly promoted HCC metastasis, while knockdown of hsa_circ_102559 reversed the promotive effects on HCC progression. Functionally, hsa_circ_102559 could target and colocalize with miR-130a-5p in the cytoplasm of HCC cells. Annexin A2 (ANXA2) was identified as a target gene of miR-130a-5p, and overexpression of ANXA2 counteracted with the suppressive effects of hsa_circ_102559 silence on HCC metastasis. Lastly, xenograft experiment was established and results indicated that knockdown of hsa_circ_102559 inhibited HCC growth and metastasis through the downregulation of ANXA2. In conclusion, hsa_circ_102559 inhibited HCC progression via sponging miR-130a-5p to reduce ANXA2 expression, suggesting that hsa_circ_102559 might be a potential biomarker or therapeutic target for HCC.

LncRNA RP11-422N16.3 Inhibits Cell Proliferation and EMT, and Induces Apoptosis in Hepatocellular Carcinoma Cells by Sponging miR-23b-3p.

OBJECTIVE: This study investigated the mechanism of RP11-422N16.3 sponging miR-23b-3p in cell proliferation, apoptosis and epithelial-mesenchymal transition (EMT) in liver cancer. METHODS: Expressions of RP11-422N16.3, miR-23b-3p and dimethylglycine dehydrogenase (DMGDH) were determined in liver cancer tissues, adjacent normal tissues, hepatocellular carcinoma cell lines and normal liver epithelial cell line. Up-regulation of RP11-422N16.3 and down-regulation of miR-23b-3p were conducted in hepatocellular carcinoma cells. Bioinformatics analysis, luciferase reporter assay and RNA-pull down assay were performed to verify the relationship among miR-23b-3p, DMGDH, as well as RP11-422N16.3. Cell proliferation and cell apoptosis were determined by CCK-8 and Flow Cytometry analysis, respectively. RESULTS: Expressions of RP11-422N16.3 and DMGDH were down-regulated while that of miR-23b-3p were up-regulated in hepatocellular carcinoma cancer tissues and cells. RP11-422N16.3 localized in cytoplasm and competitively bound to miR-23b-3p. Up-regulation of RP11-422N16.3 and down-regulation of miR-23b-3p contributed to increased expressions of DMGDH and E-cadherin, and decreased expressions of miR-23b-3p, ZEB1, Snail and Vimentin, resulting in inhibiting cell proliferation and promoting cell apoptosis. Inhibition of RP11-422N16.3 or overexpression of miR-23b-3p accelerated cell proliferation and slowed down cell apoptosis. miR-23b-3p inhibited the expression of DMGDH. CONCLUSION: Our data suggested that LncRNA RP11-422N16.3, by competitively binding to miR-23b-3p, promoted DMGDH expression, contributing to inhibit cell proliferation and EMT, and induce cell apoptosis in hepatocellular carcinoma cells.

Restoration of miRNA-148a in pancreatic cancer reduces invasion and metastasis by inhibiting the Wnt/ß-catenin signaling pathway via downregulating maternally expressed gene-3.

Various microRNAs (miRNA) have been recognized potential novel tumor markers and have a critical role in cancer development and progression. Recently, methylation of miRNA-148a was identified as a crucial biochemical process in the progression of cancer. However, its potential role and in pancreatic cancer as well as the underlying mechanisms have remained largely elusive. The present study investigated the potential antitumor effect of miR-148a as well as its impact on invasion and metastasis in pancreatic cancer. It was found that the expression of miRNA-148a and the potential predictive biomarker maternally expressed gene-3 (MEG-3) were obviously decreased in human pancreatic cancer tissues compared with those in adjacent non-tumorous tissues. Furthermore, miR-148a was found to be downregulated in pancreatic cancer cell lines compared with normal pancreatic cells through promoter methylation. An MTT assay and a clonogenic assay demonstrated that restoration of miRNA-148a inhibited the proliferation and colony formation of pancreatic cancer cells. In addition, miR-148a transduction led to the upregulation of MEG-3 expression and promoted apoptosis of pancreatic cancer cells. Western blot analysis revealed that transduction of miR-148a markedly decreased the expression levels of C-myc, cyclin D1 and ß-catenin in pancreatic cancer cells. Methylation of miR-148a not only decreased the endogenous ß-catenin levels but also inhibited the nuclear translocation of ß-catenin to delay cell cycle progression. Furthermore, ectopic miR-148a methylation inhibited pancreatic cancer cell migration and invasion via causing an upregulation of MEG-3 expression. Most importantly, ectopic overexpression of miR-148a in pancreatic cancer cells inhibited tumor formation in an animal experiment. Taken together, miR-148a methylation is a crucial regulatory process to inhibit the proliferation and invasion of pancreatic cancer cells, and transduction of miR-148a suppressed the proliferation of pancreatic cancer cells through negative regulation of the Wnt/ß-catenin signaling pathway. The findings of the present study suggested that miRNA-148a acts as a tumor suppressor in pancreatic cancer and may contribute to the development of novel treatments for pancreatic cancer.

Identification of key genes and pathways by bioinformatics analysis with TCGA RNA sequencing data in hepatocellular carcinoma.

Improved insight into the molecular characteristics of hepatocellular carcinoma (HCC) is required to predict prognosis and to develop a new rationale for targeted therapeutic strategy. Bioinformatics methods, including functional enrichment and network analysis combined with survival analysis, are required to process a large volume of data to obtain further information on differentially expressed genes (DEGs). The RNA sequencing data related to HCC in The Cancer Genome Atlas (TCGA) database were analyzed to screen DEGs, which were separately submitted to perform gene enrichment analysis to identify gene sets and signaling pathways, and to construct a protein-protein interaction (PPI) network. Subsequently, hub genes were selected by the core level in the network, and the top hub genes were focused on gene expression analysis and survival analysis. A total of 610 DEGs were identified, including 444 upregulated and 166 downregulated genes. The upregulated DEGs were significantly enriched in the Gene Ontology analysis (GO): Cell division and in the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway: Cell cycle, whereas the downregulated DEGs were enriched in GO: Negative regulation of growth and in the KEGG pathway: Retinol metabolism, with significant differences. Cyclin-dependent kinase (CDK)1 was selected as the top hub gene by the PPI network, which exhibited a similar expression trend with the data from the Gene Expression Omnibus (GEO) database. Survival analysis revealed a significantly negative correlation between CDK1 expression level and overall survival in the TCGA group (P<0.01) and the GEO group (P<0.01). Therefore, high-throughput TCGA data analysis appears to be an effective method for screening tumor molecular markers, and high expression of CDK1 is a prognostic factor for HCC.

Isocorydine suppresses doxorubicin-induced epithelial-mesenchymal transition via inhibition of ERK signaling pathways in hepatocellular carcinoma.

Doxorubicin (DOX) is a conventional and effective chemotherapeutic used in the treatment of hepatocellular carcinoma (HCC). However, doxorubicin administration may induce EMT, which results in the development of chemoresistance in HCC. Recent studies report that Isocorydine (ICD) selectively inhibits human cancer stem cells (CSCs), which have an important role in the development of chemoresistance. In this study, we observed that ICD co-administration enhanced DOX cytotoxicity in HCC cells, enabling the inhibition of DOX-induced epithelial-mesenchymal transition (EMT). Microarray data analysis revealed substantially decreased ERK signaling after ICD treatment. Additionally, we observed decreased IC50 for DOX upon ERK knockdown. Finally, we confirmed the enhanced efficacy of treatment with a combination of DOX and ICD in xenograft models. Collectively, the present study unveils the benefit of using DOX in combination with ICD for chemotherapy against HCC, revealing a novel potential anti-cancer strategy.

Ribosomal protein S15a promotes tumor angiogenesis via enhancing Wnt/ß-catenin-induced FGF18 expression in hepatocellular carcinoma.

Ribosomal protein s15a (RPS15A) plays a promotive role in the mRNA/ribosome interactions during early translation. Our previous study has found that inhibiting RPS15A expression can decrease proliferation and induce cell cycle arrest in hepatocellular carcinoma (HCC) cell lines. However, the mechanism underlying the involvement of RPS15A in HCC pathogenesis and the clinical significance of RPS15A expression remain unclear. In this study, an evaluation of RPS15A expression in 110 surgically resected HCCs and matched tumor-adjacent normal tissues revealed an overexpression of RPS15A in HCC, which was correlated with worse survival. In addition, tumor tissue with higher RPS15A expression demonstrated a higher microvascular density (MVD). Subsequently, two HCC cell lines, Huh7 (low-level constitutive RPS15A expression) and HepG2 (high RPS15A expression) were used to further evaluate the role of RPS15A in angiogenesis. The co-culture experiment of HCC cells with endothelial cells revealed that the induced overexpression of RPS15A in Huh7 cells increased the angiogenic potential of HUVEC in a paracrine fashion; conversely, knockdown of RPS15A in HepG2 cells showed an opposite effect. Further analysis indicated that RPS15A modulated FGF signaling by enhancing Wnt/beta-catenin-mediated FGF18 expression in HCC cells. FGF18, in turn, through binding to its FGFR3 receptor on endothelial cells, can activate the AKT and ERK pathway and promotes angiogenesis in a tumor microenvironment. Our in vivo experiment further confirmed that inhibition of RPS15A expression in HCC xenografts dramatically hindered tumor growth and inhibited tumor angiogenesis. Together, our findings suggest that RPS15A promotes angiogenesis in HCCs by enhancing Wnt/beta-catenin induced FGF18 expression. The RPS15A/FGF18 pathway may be a rational target for anti-angiogenic therapy of HCC.

EphA1 activation promotes the homing of endothelial progenitor cells to hepatocellular carcinoma for tumor neovascularization through the SDF-1/CXCR4 signaling pathway.

BACKGROUND: Endothelial progenitor cells (EPCs) can migrate to the tumor tissue and enhance the angiogenesis of hepatocellular carcinoma (HCC); thus, they are associated with a poor prognosis. However, the specific molecular mechanism underlying the homing of EPCs to the HCC neovasculature remains unrevealed. METHODS: Co-culture experiments of endothelial progenitor cells with HCC cells with modulation of EphA1 were performed in vitro. Using EPCs as angiogenic promoters by injecting them into HCC xenograft-bearing nude mice via their tail veins to test homing ability of EPCs changed according to different EphA1 level in HCC xenograft. RESULTS: In this study, we found that the up-regulation of EphA1 expression in HCC cells could affect not only the chemotaxis of EPCs to tumor cells and endothelial cells (ECs) but also the tube formation ability of EPCs in a paracrine fashion. Further, we revealed that the increased expression of EphA1 in HCC cells led to an increased SDF-1 concentration in the tumor microenvironment, which in turn activated the SDF-1/CXCR4 axis and enhanced the recruitment of EPCs to HCC. In addition, the EphA1-activated SDF-1 expression and secretion was partially mediated by the PI3K and mTOR pathways. In vivo experiments demonstrated that blocking EphA1/SDF-1/CXCR4 signaling significantly inhibited the growth of HCC xenografts. Using immunohistochemistry and immunofluorescence assays, we verified that the inhibition of tumor angiogenesis was at least partially caused by the decreased number of EPCs homing to tumor tissue. CONCLUSIONS: Our findings indicate that targeting the EphA1/SDF-1 signaling pathway might be a therapeutic anti-angiogenesis approach for treating HCC.