Sorafenib down-regulates expression of HTATIP2 to promote invasiveness and metastasis of orthotopic hepatocellular carcinoma tumors in mice.

BACKGROUND & AIMS: Antiangiogenic agents can sometimes promote tumor invasiveness and metastasis, but little is known about the effects of the antiangiogenic drug sorafenib on progression of hepatocellular carcinoma (HCC). METHODS: Sorafenib was administered orally (30 mg · kg(-1) · day(-1)) to mice with orthotopic tumors grown from HCC-LM3, SMMC7721, or HepG2 cells. We analyzed survival times of mice, along with tumor growth, metastasis within liver and to lung, and induction of the epithelial-mesenchymal transition. Polymerase chain reaction arrays were used to determine the effects of sorafenib on gene expression patterns in HCC cells. We analyzed regulation of HIV-1 Tat interactive protein 2 (HTATIP2) by sorafenib and compared levels of this protein in tumor samples from 75 patients with HCC (21 who received sorafenib after resection and 54 who did not). RESULTS: Sorafenib promoted invasiveness and the metastatic potential of orthotopic tumors grown from SMMC7721 and HCC-LM3 cells but not from HepG2 cells. In gene expression analysis, HTATIP2 was down-regulated by sorafenib. HCC-LM3 cells that expressed small hairpin RNAs against HTATIP2 (knockdown) formed less invasive tumors in mice following administration of sorafenib than HCC-LM3 without HTATIP2 knockdown. Alternatively, HepG2 cells that expressed transgenic HTATIP2 formed more invasive tumors in mice following administration of sorafenib. Sorafenib induced the epithelial-mesenchymal transition in HCC cell lines, which was associated with expression of HTATIP2. Sorafenib regulated expression of HTATIP2 via Jun-activated kinase (JAK) and signal transducer and activator of transcription (STAT)3 signaling. Sorafenib therapy prolonged recurrence-free survival in patients who expressed lower levels of HTATIP2 compared with higher levels. CONCLUSIONS: Sorafenib promotes invasiveness and the metastatic potential of orthotopic tumors from HCC cells in mice, down-regulating expression of HTATIP2 via JAK-STAT3 signaling.

Antiangiogenic effects of pazopanib in xenograft hepatocellular carcinoma models: evaluation by quantitative contrast-enhanced ultrasonography.

BACKGROUND: Antiangiogenesis is a promising therapy for advanced hepatocellular carcinoma (HCC), but the effects are difficult to be evaluated. Pazopanib (GW786034B) is a pan-vascular endothelial growth factor receptor inhibitor, the antitumor effects or antiangiogenic effects haven't been investigated in HCC. METHODS: In vitro direct effects of pazopanib on human HCC cell lines and endothelial cells were evaluated. In vivo antitumor effects were evaluated in three xenograft nude mice models. In the subcutaneous HCCLM3 model, intratumoral blood perfusion was detected by contrast-enhanced ultrasonography (CEUS), and serial quantitative parameters were profiled from the time-intensity curves of ultrasonograms. RESULTS: In vitro proliferation of various HCC cell lines were not inhibited by pazopanib. Pazopanib inhibited migration and invasion and induced apoptosis significantly in two HCC cell lines, HCCLM3 and PLC/PRF/5. Proliferation, migration, and tubule formation of human umbilical vein endothelial cells were inhibited by pazopanib in a dose-dependent manner. In vivo tumor growth was significantly inhibited by pazopanib in HCCLM3, HepG2, and PLC/PRF/5 xenograft models. Various intratumoral perfusion parameters changed over time, and the signal intensity was significantly impaired in the treated tumors before the treatment efficacy on tumor size could be observed. Mean transit time of the contrast media in hotspot areas of the tumors was reversely correlated with intratumoral microvessel density. CONCLUSIONS: Antitumor effects of pazopanib in HCC xenografts may owe to its antiangiogenic effects, and the in vivo antiangiogenic effects could be evaluated by quantitative CEUS.

Bevacizumab enhances chemosensitivity of hepatocellular carcinoma to adriamycin related to inhibition of survivin expression.

PURPOSE: In recent years, anti-angiogenesis drugs have shown promising clinical effects against many tumors, particularly in combination with chemotherapy. Although the combination has become a standard of care for many tumors, the mechanisms of the chemosensitizing activity of anti-angiogenic drugs are not fully understood. Here, we sought to determine if anti-angiogenesis drug bevacizumab could enhance the chemosensitivity of HCC by inhibition of survivin. METHODS: After treatment of human umbilical vein endothelial cells (HUVECs) and hepatocellular carcinoma (HCC) cell line PLC/PRF/5 (PLC) with bevacizumab or/and adriamycin, the direct effects were examined by survival assays, and the expression of Akt, Phospho-Akt and survivin were evaluated by western blot. Tumor growth was observed in a human HCC xenograft nude mouse model treated with different drugs, and the expression of PCNA, CD31 and survivin in tumor tissues were evaluated by means of immunohistochemistry. RESULTS: Bevacizumab enhanced the chemosensitivity of HCC by inhibiting the VEGF-PI3 K/Akt-survivin signaling cascade in endothelial cells. The combination of bevacizumab with adriamycin therapy resulted in better outcomes compared with monotherapy in hepatocellular carcinoma xenografts; bevacizumab significantly inhibited tumor angiogenesis and growth. In addition, bevacizumab reduced survivin expression in tumor tissues, including tumor vascular endothelial cells in vivo, although it did not inhibit survivin expression in tumor cells in vitro. CONCLUSION: These results implicate the bevacizumab-increased efficacy of adriamycin via an inhibition of survivin expression in malignant cells as well as tumor vasculature cells, which provides other insights into the mechanism of enhanced efficacy by combination of VEGF blocker and chemotherapeutic agents.

Long-term interferon-α treatment suppresses tumor growth but promotes metastasis capacity in hepatocellular carcinoma.

PURPOSE: To elucidate the effect of IFN-α treatment on tumor growth and metastasis of hepatocellular carcinoma (HCC). METHODS: IFN-α administration was conducted in nude mice using an orthotopic implantation model of human HCC, and the key molecular markers in the IFN-α treatment was detected by immunohistochemistry staining and PCR array. RESULTS: Up to 12 weeks of IFN-α treatment significantly suppressed tumor growth of HCC, but relatively increased the number of circulating tumor cells, which might be due to the enhanced tumor hypoxia as well as up-regulation of metastasis-related genes, such as HIF-1α, c-met, u-PA, PDGF-A, and IL-8. However, IFN-α had no direct effect on migration and invasion of HCC cells. CONCLUSIONS: IFN-α has janus face of consistently suppressing HCC growth, however, promoting tumor metastasis capacity, which is of clinical indication for the scientific administration of IFN-α and the similar antiangiogenesis drugs for their dual effect on tumor growth and metastasis.

Depletion of tumor-associated macrophages enhances the effect of sorafenib in metastatic liver cancer models by antimetastatic and antiangiogenic effects.

PURPOSE: To investigate the role of macrophages in tumor progression under sorafenib treatment and to explore whether combination of drugs that deplete macrophages improved the antitumor effect of sorafenib. EXPERIMENTAL DESIGN: Tumor growth, lung metastasis, and tumor angiogenesis were observed in HCCLM3-R and SMMC7721, two human hepatocellular carcinoma xenograft nude mouse models, when treated with sorafenib (30 mg/kg daily, n = 6 per group) or a vehicle as control. Macrophage infiltration was measured in the peripheral blood and in sorafenib-treated tumor by immunohistochemistry and flow cytometry with F4/80 antibody and CD11b antibody. The effect of macrophage depletion on tumor angiogenesis and metastasis after sorafenib treatment, using two drug target macrophages, zoledronic acid (ZA) and clodrolip, was measured in the two models of hepatocellular carcinoma. RESULTS: Although sorafenib significantly inhibited tumor growth and lung metastasis, it induced a significant increase in peripheral recruitment and intratumoral infiltration of F4/80- and CD11b-positive cells, which was accompanied with elevation of colony-stimulating factor-1, stromal-derived factor 1alpha, and vascular endothelial growth factor in the tumor and elevation of plasma colony-stimulating factor-1 and mouse vascular endothelial growth factor in peripheral blood, suggesting the role of macrophages in tumor progression under sorafenib treatment. Depletion of macrophages by clodrolip or ZA in combination with sorafenib significantly inhibited tumor progression, tumor angiogenesis, and lung metastasis compared with mice treated with sorafenib alone. ZA was more effective than clodrolip. CONCLUSIONS: Macrophages may have an important role in tumor progression under sorafenib treatment. ZA is promising when combined with sorafenib to enhance its antitumor effect.

Protein expression profiling of vascular endothelial growth factor and its receptors identifies subclasses of hepatocellular carcinoma and predicts survival.

PURPOSE: To examine expression profile and prognostic significance of vascular endothelial growth factor (VEGF) and its receptors in hepatocellular carcinoma (HCC) and peritumoral tissue. METHODS: Expression of VEGF-A, VEGF-C, and VEGF receptor 1(VEGFR-1), VEGFR-2, and VEGFR-3 in tumor and peritumoral liver tissue was studied by immunohistochemistry in a tissue microarray from 107 patients with HCC. Unsupervised hierarchical cluster analyses were conducted to identify relevant clusters. RESULTS: Staining of VEGF-A, VEGF-C, VEGFR-2, and VEGFR-3 was mostly found on the tumor cells and peritumoral hepatocytes, but VEGFR-1 was mostly expressed in stromal cells. In most of the cases, the expression of VEGF-A, VEGFR-1, VEGFR-2, and VEGFR-3 in was higher in peritumoral liver tissue, while VEGF-C expression was higher in tumor. Unsupervised hierarchical clustering analysis identified four prognostically different clusters, of which cluster A was classified into the "poor prognosis group," and the other three clusters were classified into the "good prognosis group" (P = 0.047). Further analysis with a set of seven markers reproduced the same four cluster groups with significantly different recurrence free probability (RFP) (P = 0.018), and the low RFP group was associated with more intrahepatic satellite lesions. Multivariate analysis showed that classification defined by seven biomarkers was of prognostic significance (P = 0.000). CONCLUSIONS: Expression of VEGF and its receptors was higher in peritumoral tissue than in tumor in HCC. Seven biomarkers predicted patients' RFP, which consisted of tumoral expression of VEGF-A, VEGFR-1, and VEGF-C as well as peritumoral expression of VEGF-A, VEGFR-1, VEGFR-2, and VEGFR-3.

Human hepatocellular carcinoma tumor-derived endothelial cells manifest increased angiogenesis capability and drug resistance compared with normal endothelial cells.

PURPOSE: Increasing evidence indicates that tumor-derived endothelial cells (TEC) possess a distinct and unique phenotype compared with endothelial cells (NEC) from adjacent normal tissue and may be able to acquire resistance to drugs. The aim of this study was to investigate the angiogenesis activity and response to drug treatment of TECs and NECs derived from human hepatocellular carcinoma (HCC). EXPERIMENTAL DESIGN: TECs or NECs were isolated from HCC or adjacent normal liver tissue using anti-CD105 antibody coupled to magnetic beads. The phenotypic and functional properties of endothelial cells were characterized by testing the expression of CD105, CD31, CD144, vascular endothelial growth factor receptor-1, vascular endothelial growth factor receptor-2, and von Willebrand factor, and the ability of DiI-Ac-LDL-uptake and tube formations. CD105(+) TECs were compared with CD105(+) NECs and human umbilical vein endothelial cells (HUVEC) by examining their ability to proliferate, motility, ability to adhere to tumor cells, response to tumor conditioned medium, and reactions to the chemotherapy drugs Adriamycin and 5-fluorouracil and the antiangiogenic drug sorafenib. RESULTS: Compared with CD105(+) NECs and HUVECs, CD105(+) TECs showed increased apoptosis resistance and motility and proangiogenic properties. Meanwhile, CD105(+) TECs had a greater ability to adhere to tumor cells and survive in the tumor environment. Moreover, CD105(+) TECs acquired more resistance to Adriamycin, 5-fluorouracil, and sorafenib than CD105(+) NECs and HUVECs. CONCLUSIONS: TECs possessed enhanced angiogenic activity and resistance to chemotherapeutic drugs and an angiogenesis inhibitor, and may provide a better tool for studying tumor angiogenesis and antiangiogenesis drugs in HCC.

High expression of macrophage colony-stimulating factor in peritumoral liver tissue is associated with poor survival after curative resection of hepatocellular carcinoma.

PURPOSE: To investigate prognostic values of the intratumoral and peritumoral expression of macrophage colony-stimulating factors (M-CSF) in hepatocellular carcinoma (HCC) patients after curative resection. PATIENTS AND METHODS: Expression of M-CSF and density of macrophages (M Phi) were assessed by immunohistochemistry in tissue microarrays containing paired tumor and peritumoral liver tissue from 105 patients who had undergone hepatectomy for histologically proven HCC. Prognostic value of these and other clinicopathologic factors was evaluated. RESULTS: Neither intratumoral M-CSF nor M Phi density was associated with overall survival (OS) or disease-free survival (DFS). High peritumoral M-CSF and M Phi density, which correlated with large tumor size, presence of intrahepatic metastasis, and high TNM stage, were independent prognostic factors for both OS (P = .001 and P < .001, respectively) and DFS (P = .001 and P = .003, respectively) and affected incidence of early recurrence. In a small HCC subset, peritumoral M-CSF was also correlated with both OS and DFS (P = .038 and P = .001, respectively). The combination of peritumoral M-CSF and M Phi had a better power to predict the patients' death and disease recurrence (P < .001 for both). CONCLUSION: High peritumoral M-CSF and M Phi were associated with HCC progression, disease recurrence, and poor survival after hepatectomy, highlighting the importance of peritumoral tissue in the recurrence and metastasis of HCC. M-CSF and M Phi may be targets of postoperative adjuvant therapy.

[Construction of a trans-splicing ribozyme for restoring EGFP truncation mutation].

Special designed group I intron ribozymes can specifically splice objective RNA, repair the mutant gene in RNA level. The specificity of ribozyme is determined by nucleotides specific internal guide sequence (IGS) introduced to the enzyme. In this study, fragment sequence containing Tetrahymena thermophilia intron I of 26S rRNA gene was cloned and cis-splicing activity of this ribozyme was confirmed by in vitro transcription. For evaluating the trans-splicing activity of this ribozyme, a truncated mutant Green Fluorescence Protein (GFP) vector, XYQ5/XYQ10- pEGFP-C2, was constructed. This vector deleted the 3' end 564bp fragment of EGFP coding sequence, led to the lost the activity of emitting green fluorescence. Trans-splicing ribozyme plasmids ptrans-rib-CMV2 for remedy of the truncated mutant EGFP was constructed by PCR and molecular cloning techniques. This vector utilizing cloned 26S rRNA intron 1 as core enzyme; selecting T-G site at 194bp of EGFP coding sequence as splicing receptor, designed an IGS which is inversely complement to the 188-193nt of EGFP mRNA; the 195-890bp fragment of EGFP coding sequence was ligated to the 3'-end of ribozyme core. The fragment containing these components was inserted to a eukayotic expression vector pRC-CMV2. Using linearized XYQ5/XYQ10- pEGFP-C2 and ptrans-rib-CMV2 as templates, truncated EGFP mRNA and the constructed ribozyme vector were transcribed and mixed to evaluate the trans-splicing activity. Analysis of in vitro transcription products mix by RT-PCR verified the existence of wild type EGFP mRNA molecule. Co-transfection of XYQ5/XYQ10- pEGFP-C2 with ptrans-rib-CMV2 to Hela cells proved this ribozyme restored green fluorescence within cell, but the efficiency was low.