Article

Overexpression of HIF-1α in primary gallbladder carcinoma and its relation to vasculogenic mimicry and unfavourable prognosis

Department of Surgery, Tongji Hospital, Tongji University School of Medicine, Shanghai, PR China.
Oncology Reports (Impact Factor: 2.3). 06/2012; 27(6):1990-2002. DOI: 10.3892/or.2012.1746
Source: PubMed

ABSTRACT

As a novel mode of tumor neovascularization, vasculogenic mimicry (VM) has been reported to increase tumor-related mortality in many different solid tumors. In the present study, two established human gallbladder carcinoma (GBC) cell lines (highly aggressive GBC-SD and poorly aggressive SGC-996) cultured on a three-dimensional matrix were assessed for the ability of VM channel formation under normoxic or hypoxic conditions. In addition, the relationship between HIF-1α gene expression and VM channel formation of GBC cells in vitro was measured using the small interfering RNA (siRNA) technique, western blotting and real-time reverse transcription (RT)-PCR analysis. Furthermore, H&E and CD31/periodic acid-Schiff (PAS) staining were used to observe VM in GBC tissue samples. Additionally, all seventy-one specimens with VM and non-VM were stained for hypoxia inducible factor-1 α (HIF-1α) and its correlation with clinicopathological features and prognosis was analyzed simultaneously. We found that hypoxia could induce more VM channel formation and elevated HIF-1α expression in highly aggressive GBC-SD cells. HIF-1α siRNA efficiently knocked down HIF-1α expression and GBC VM networks under either normoxic or hypoxic conditions. VM was present in human primary GBC and overexpression of HIF-1α was significantly correlated with depth of invasion and perineural involvement in the non-VM group. Moreover, VM and HIF-1α were independent factors for the overall survival of GBC patients and correlated with decreased survival. In conclusion, VM was present in human GBC. As a critical mediator in VM formation, high expression of HIF-1α was associated with VM and tumor progression in GBC patients.

  • Source
    • "Because VM is an alternative pathway for highly aggressive tumors to guarantee their blood supply, whereas not an angiogenic event arising from pre-existing vessels, it is necessary to find potential therapeutic approaches for targeting VM or in addition to antiangiogenic therapies [23]–[25]. We reported that VM existed in human gallbladder cancers, highly aggressive gallbladder cancer GBC-SD cells and xenografts; whereas poorly aggressive SGC-996 cells did not form the VM networks under the same conditions [13], [17], [18], [42]. In this study, the results showed that NCTD, similar to TIMP-2, inhibited tumor growth and VM formation of GBC-SD xenografts, and prolonged survival time of the xenograft mice. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Vasculogenic mimicry (VM) is a newly-defined tumor microcirculation pattern in highly aggressive malignant tumors. We recently reported tumor growth and VM formation of gallbladder cancers through the contribution of the ephrin type a receptor 2 (EphA2)/focal adhesion kinase (FAK)/Paxillin signaling pathways. In this study, we further investigated the anti-VM activity of norcantharidin (NCTD) as a VM inhibitor for gallbladder cancers and the underlying mechanisms. In vivo and in vitro experiments to determine the effects of NCTD on tumor growth, host survival, VM formation of GBC-SD nude mouse xenografts, and vasculogenic-like networks, malignant phenotypes i.e., proliferation, apoptosis, invasion and migration of GBC-SD cells. Expression of VM signaling-related markers EphA2, FAK and Paxillin in vivo and in vitro were examined by immunofluorescence, western blotting and real-time polymerase chain reaction (RT-PCR), respectively. The results showed that after treatment with NCTD, GBC-SD cells were unable to form VM structures when injecting into nude mouse, growth of the xenograft was inhibited and these observations were confirmed by facts that VM formation by three-dimensional (3-D) matrix, proliferation, apoptosis, invasion, migration of GBC-SD cells were affected; and survival time of the xenograft mice was prolonged. Furthermore, expression of EphA2, FAK and Paxillin proteins/mRNAs of the xenografts was downregulated. Thus, we concluded that NCTD has potential anti-VM activity against human gallbladder cancers; one of the underlying mechanisms may be via blocking the EphA2/FAK/Paxillin signaling pathway.
    Full-text · Article · May 2014 · PLoS ONE
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Vasculogenic mimicry (VM) is a new tumor blood supply in some highly aggressive malignant tumors. We previously reported VM in human gallbladder carcinomas, 3-D matrices in vitro and nude mouse xenografts in vivo of highly aggressive GBC-SD cells and its clinical significance. In this study, we further studied the underlying mechanisms of VM in gallbladder carcinomas via the 3-D matrix in vitro, the nude mouse xenografts in vivo of GBC-SD or SGC-996 cells, immunohistochemistry (H&E staining and CD31-PAS double staining), electron microscopy, expression of MMP-2, MT1-MMP, PI3K, Ln-5γ2, EphA2, FAK and Paxillin-P proteins/mRNAs determined by SABC, ELISA, immunofluorescence, western blotting and qRT-PCR, respectively. It was shown that all of untreated highly aggressive GBC-SD cells and xenografts formed vasculogenic-like structures within 2 weeks of seeding and injecting, and facilitated the growth of tumor cells or xenografts; whereas poorly aggressive SGC-996 cells or GBC-SD cells treated by TIMP-2 were unable to form the vasculogenic-like structures with the same conditions; and tumor xenograft growth was inhibited. Expression of MMP-2, MT1-MMP proteins/mRNAs from sections and supernates of 3-D matrix in vitro, expression of PI3K, MMP-2, MT1-MMP, Ln-5γ2, EphA2, FAK and Paxillin-P proteins/mRNAs from sections of xenografts in vivo in untreated GBC-SD group was upregulated significantly (all P<0.001); however, expression of these VM signal-related proteins/mRNAs in the SGC-996 group and GBC-SD treated by the TIMP-2 group was significantly downregulated (all P<0.001). Thus, we identified for the first time that highly aggressive GBC-SD cells formed VM in vitro and in vivo through the upregulation of PI3K/MMPs/Ln-5γ2 and/or EphA2/FAK/Paxillin signaling. PI3K/MMPs/Ln-5γ2 and EphA2/FAK/Paxillin as key signaling pathways in a coordinated manner contributed to tumor growth and VM of gallbladder carcinomas and provided novel targets that could be potentially exploited for therapeutic intervention of human gallbladder carcinomas.
    Preview · Article · Apr 2013 · International Journal of Oncology
  • [Show abstract] [Hide abstract]
    ABSTRACT: This study aims to find good markers for predicting the prognosis of patients with esophageal squamous cell carcinoma (ESCC). Vasculogenic mimicry (VM) and the expression of hypoxia inducible factor-lα (HIF-lα)/E-cad protein in ESCC were investigated by immunostaining. The association between VM, HIF-lα/E-cad and clinicopathologic characteristics and 5-year-survival rate of patients with ESCC was analyzed. A total of 160 ESCC specimens were involved in this study and 28 specimens of normal esophageal mucosa served as controls. VM channels were identified in 78 (48.75%) of the 160 ESCC specimens and none of the normal esophageal mucosa was found to have VM. The rates of high-expression of HIF-lα and E-cad in ESCC were 43.75% and 38.75%, while the rates in control were 17.86% and 71.43%, respectively (P<0.05 for all). VM and the expression levels of HIF-lα and E-cad were significantly related to lymph node metastasis, serosa infiltration, PTNM staging and 5-year-survival rates of patients with ESCC (P<0.05 for all). VM was positively correlated with HIF-lα but negatively with E-cad, and HIF-lα was negatively correlated with E-cad (P<0.001 for all). The 5-year-survival rate of patients with ESCC was 6.41% (5/78) in VM group and 65% (52/82) in non-VM group, 7.14% (5/70) in high HIF-lα expression group and 57.78% (52/90) in low HIF-lα expression group. Oppositely, the 5-year-survival rate in high E-cad expression group was 80.65% (50/62) and that in low E-cad expression group was 7.37% (7/98) (P<0.05 for all). Cox multifactor regression analysis indicated that lymph node metastasis, PTNM stage, VM and expression levels of HIF-lα and E-cad were independent risk factors of patients with ESCC (P<0.05 for all). Combined detection of VM, HIF-lα and E-cad plays an important role in predicting the invasion, metastasis and prognosis of patients with ESCC.
    No preview · Article · Jun 2013 · Journal of Huazhong University of Science and Technology
Show more