Li-Feng Liu

Tumorigenesis and prognostic role of hepatoma-derived growth factor in human gliomas

Hepatoma-derived growth factor (HDGF) is a neurotrophic factor found in mouse spinal cord and hippocampal neurons. In various malignant tumors, the role of HDGF in tumor progression and its use as a diagnostic biomarker or therapeutic target have been extensively explored. However, the prognostic function and mitogenic role of HDGF in gliomagenesis are yet to be verified. In this study, we found a significant incidence of HDGF prevalence between the different pathological types and stages of glioma in 105 patients. We also found a prognostic significance in 41 glioblastoma multiforme (GBM) patients, with prevalence of nuclear HDGF predicting short survival of patients with GBM after surgery. To delineate the mitogenic role of HDGF in gliomagenesis, an adenoviral-expressed HDGF small interfering RNA (Ad-HDGF siRNA) was used to knock down expression of nuclear HDGF. After knocking down nuclear HDGF expression in human GBM cells, cell growth and cell invasion and induction on apoptosis by caspase-3 activation were significantly inhibited. We conclude that HDGF is a mitogenic growth factor in glioma progression and can be a useful prognostic marker for GBM and therapeutic target for clinical management of glioma in the future.

Glial Cell Line–Derived Neurotrophic Factor Gene Transfer Exerts Protective Effect on Axons in Sciatic Nerve Following Constriction-Induced Peripheral Nerve Injury

Damage to peripheral nerves following trauma or neurodegenerative diseases often results in various sensory and motor abnormalities and chronic neuropathic pain. The loss of neurotrophic factor support has been proposed to contribute to the development of peripheral neuropathy. The main objective of this study was to investigate the protective effect of glial cell line-derived neurotrophic factor (GDNF) using peripheral gene delivery in a rat model of constriction-induced peripheral nerve injury. In this study, it was shown that mechanical and thermal hypersensitivity increased on the injured limb at day 7 after chronic constrictive injury (CCI) was induced. The neurological changes were correlated with the structural changes and loss of GDNF/Akt signaling, particularly in the distal stump of the injured sciatic nerve. Subsequently, recombinant adenovirus was employed to evaluate the potential of intramuscular GDNF gene delivery to alleviate the CCI-induced nerve degeneration ad neuropathic pain. After CCI for 3 days, intramuscular injection of adenovirus encoding GDNF (Ad-GDNF) restored the protein level and activity of GDNF/Akt signaling pathway in the sciatic nerve. This was associated with an improved myelination profile and behavioral outcomes in animals with CCI. In conclusion, the present study demonstrates the involvement of GDNF loss in the pathogenesis of CCI-induced neuropathic pain and the therapeutic potential of intramuscular GDNF gene delivery for the treatment of peripheral nerve degeneration.

Up-Regulation of Hepatoma-Derived Growth Factor Facilities Tumor Progression in Malignant Melanoma

Cutaneous malignant melanoma is the fastest increasing malignancy in humans. Hepatoma-derived growth factor (HDGF) is a novel growth factor identified from human hepatoma cell line. HDGF overexpression is correlated with poor prognosis in various types of cancer including melanoma. However, the underlying mechanism of HDGF overexpression in developing melanoma remains unclear. In this study, human melanoma cell lines (A375, A2058, MEL-RM and MM200) showed higher levels of HDGF gene expression, whereas human epidermal melanocytes (HEMn) expressed less. Exogenous application of HDGF stimulated colony formation and invasion of human melanoma cells. Moreover, HDGF overexpression stimulated the degree of invasion and colony formation of B16–F10 melanoma cells whereas HDGF knockdown exerted opposite effects in vitro. To evaluate the effects of HDGF on tumour growth and metastasis in vivo, syngeneic mouse melanoma and metastatic melanoma models were performed by manipulating the gene expression of HDGF in melanoma cells. It was found that mice injected with HDGF-overexpressing melanoma cells had greater tumour growth and higher metastatic capability. In contrast, mice implanted with HDGF-depleted melanoma cells exhibited reduced tumor burden and lung metastasis. Histological analysis of excised tumors revealed higher degree of cell proliferation and neovascularization in HDGF-overexpressing melanoma. The present study provides evidence that HDGF promotes tumor progression of melanoma and targeting HDGF may constitute a novel strategy for the treatment of melanoma.

Downregulation of Hepatoma-derived Growth Factor Contributes to Retarded Lung Metastasis via inhibition of Epithelial-Mesenchymal Transition by Systemic POMC Gene Delivery in Melanoma

The prognosis of malignant melanoma is poor due to high incidence of metastasis, underscoring the demand for development of novel therapeutic strategies. Stress hormone pro-opiomelanocortin (POMC) is the precursor for several anti-inflammatory peptides that hold promise for management of cancer-related diseases. The present study evaluated the antimetastatic potential and mechanism of POMC therapy for metastatic melanoma. Adenovirus-mediated POMC gene delivery potently inhibited the invasiveness of human and mouse melanoma cells. Moreover, after induction of lung metastasis, systemic POMC expression significantly reduced the foci formation and neovascularization in lungs. Mechanistic studies revealed that POMC therapy inhibited the epithelial–mesenchymal transition (EMT) of melanoma cells by upregulation of E-cadherin and downregulation of vimentin and α-smooth muscle actin (α-SMA). In addition, microarray analysis unveiled POMC gene transfer reduced the mRNA level of multiple prometastatic factors, including hepatoma-derived growth factor (HDGF). Cell culture and immunohistochemical studies further confirmed that POMC gene delivery significantly decreased the expression of HDGF in melanoma cells and tissues. Despite stimulating the invasion and EMT, exogenous HDGF supply only partially attenuated the POMC-mediated invasion inhibition and EMT change in melanoma cells. Finally, we delineated the contribution of melanocortins to POMC-induced inhibition of invasion, HDGF downregulation, and E-cadherin upregulation. Together, these results indicate that HDGF downregulation participates in POMC-induced suppression of metastasis and EMT in melanoma. Mol Cancer Ther; 12(6); 1016–25. ©2013 AACR.

Systemic Pro-opiomelanocortin Expression Induces Melanogenic Differentiation and Inhibits Tumor Angiogenesis in Established Mouse Melanoma

Malignant melanoma is one of the leading causes of cancer mortality worldwide, underlining the need for effective novel therapies. In this study, the therapeutic efficacy and mechanism of systemic pro-opiomelanocortin (POMC) therapy were evaluated in mice bearing established melanoma. Injection of adenovirus encoding POMC (Ad-POMC) led to hepatic POMC overexpression and elevated adrenocorticotropin (ACTH) levels in the circulation. Systemic POMC therapy significantly attenuated the growth of established melanoma and prolonged the survival of tumor-bearing mice. Histological analysis revealed that systemic POMC therapy induced melanogenic differentiation while reducing melanoma growth. In addition, POMC therapy also elicited a significant reduction in the neovascular network of melanoma. Last, we demonstrated that POMC-derived peptides, including ACTH, α-melanocyte-stimulating hormone (α-MSH), and β-MSH, are involved in POMC-mediated melanogenic differentiation and angiogenesis inhibition. In summary, systemic POMC therapy suppresses melanoma growth via induction of melanogenic differentiation and angiogenesis blockade, thereby demonstrating its potential as a novel treatment modality for melanoma.

Pro-opiomelanocortin gene delivery suppresses the growth of established Lewis lung carcinoma through a melanocortin-1 receptor-independent pathway

Pro‐opiomelanocortin (POMC) is the precursor of several neuropeptides, such as corticotropin, melanocyte‐stimulating hormone and the endogenous opioid (β‐endorphin). Our previous studies have indicated that POMC gene delivery inhibited the progression and metastasis of B16‐F10 melanoma via the α‐ melanocyte‐stimulating hormone/melanortin‐1 receptor (MC‐1R) pathway.

Enhancement of neurite outgrowth in neuron cancer stem cells by growth on 3-D collagen scaffolds

Collagen is one component of the extracellular matrix that has been widely used for constructive remodeling to facilitate cell growth and differentiation. The 3-D distribution and growth of cells within the porous scaffold suggest a clinical significance for nerve tissue engineering. In the current study, we investigated proliferation and differentiation of neuron cancer stem cells (NCSCs) on a 3-D porous collagen scaffold that mimics the natural extracellular matrix. We first generated green fluorescence protein (GFP) expressing NCSCs using a lentiviral system to instantly monitor the transitions of morphological changes during growth on the 3-D scaffold. We found that proliferation of GFP-NCSCs increased, and a single cell mass rapidly grew with unrestricted expansion between days 3 and 9 in culture. Moreover, immunostaining with neuronal nuclei (NeuN) revealed that NCSCs grown on the 3-D collagen scaffold significantly enhanced neurite outgrowth. Our findings confirmed that the 80 μm porous collagen scaffold could enhance attachment, viability and differentiation of the cancer neural stem cells. This result could provide a new application for nerve tissue engineering and nerve regeneration.

Abstract 2786: Downregulated expression of hepatoma-derived growth factor (HDGF) reduces glioma cancer cell tumor growth and angiogenesis

Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA Hepatoma derived growth factor (HDGF) is a mitogenic growth factor in the progression of human glioma. In this paper, we study the gliomagenesis role of HDGF in syngenic glioma rat model by Lenti-virus sh-HDGF (LV-shHDGF) infection. The tumor inhibition of HDGF depletion in rat glioma C6 cells was measured by MRI scanning. We found all glioma tumors growth after implanting but only HDGF knock down tumors had a significant reduction in the tumor size at the 4th-week MRI-scanning. After tumor volume was quantified on serial brain section, we found a 10-folds of reduction in the tumor size was observed in HDGF knock down tumors than scrambles (p<0.005). By survival analysis, rats with gliomas had a less median survival of 25 days and the HDGF knock down group was still alive from the time point of implanting. According to the pathological analysis, the HDGF knock down tumors presented a significant cell apoptosis and reduction in the Ki67 mitotic index, CD31 angiogenesis index, and ANG-4 that exhibited markedly reduced tumor growth and blood vessel formation than controls. In addition, Western blot analysis showed exogenous HDGF increased the expression of PI3K, phospho-Akt, phospho-FAK, phospho-MDM2, PCNA and transcription factors of Iκ-B, NF-κB, cFos, ANG-4, and HIF-α in a dose-dependent manner; however, these tumorigenesis moleculars were significantly decreased in HDGF knock down cells. We concluded that HDGF is a mitogenic growth factor in the progression of glioma and it can be a useful therapeutic target for clinical management of glioma in the future. Note: This abstract was not presented at the meeting. Citation Format: Li-Feng Liu, Shu-Shong Hsu, Chih-Hao Chen. Downregulated expression of hepatoma-derived growth factor (HDGF) reduces glioma cancer cell tumor growth and angiogenesis. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2786. doi:10.1158/1538-7445.AM2014-2786

ATPS-80ANTI-TUMORIGENESIS OF LENTI-VIRUS sh-HDGF IN RAT C6 GLIOMA MODEL

BACKGROUND: In our previous studies, we found Hepatoma derived growth factor (HDGF) is a mitogenic growth factor in the progression of human glioma. METHODS: In this paper, we study the gliomagenesis role of HDGF in syngenic glioma rat model by Lenti-virus sh-HDGF (LV-shHDGF) infection and tumors growth inhibition was analysis by MRI scanning and western blot analysis. This work was supported by NSC101-2314-B-075B-003-MY2 and VGHKS102-022. RESULTS: We found all glioma tumors growth after implanting but only HDGF knock down tumors had a significant reduction in the tumor size at the 4th-week MRI-scanning. After tumor volume was quantified on serial brain section, we found a 10-folds of reduction in the tumor size was observed in HDGF knock down tumors than scrambles (p < 0.005). By survival analysis, rats with gliomas had a less median survival of 25 days and the HDGF knock down group was still alive from the time point of implanting. According to the pathological analysis, the HDGF knock down tumors presented a significant cell apoptosis and reduction in the Ki67 mitotic index, CD31 angiogenesis index, and ANG-4 that exhibited markedly reduced tumor growth and blood vessel formation than controls. In addition, Western blot analysis showed exogenous HDGF increased the expression of PI3K, phospho-Akt, phospho-FAK, phospho-MDM2, PCNA and transcription factors of Ik-B, NF-kB, cFos, ANG-4, and HIF-a in a dose-dependent manner; however, these tumorigenesis moleculars were significantly decreased in HDGF knock cells. CONCLUSIONS: We concluded that HDGF is a mitogenic growth factor in the progression of glioma and it can be a useful therapeutic target for clinical management of glioma in the future.

Abstract 5627: Tumorigenesis and prognostic role of hepatoma-derived growth factor in human gliomas

Proceedings: AACR 103rd Annual Meeting 2012‐‐ Mar 31‐Apr 4, 2012; Chicago, IL Hepatoma derived growth factor (HDGF) is a neurotrophic factor found in mouse spinal cord and hippocampal neurons. In various malignant tumors, the role of HDGF in tumor progression and its use as a diagnostic biomarker or therapeutic target have been extensively explored. However, the prognostic function and mitogenic role of HDGF in gliomagenesis is yet to be verified. In this study, we found a significant incidence of HDGF prevalence between the different pathological types and stages of glioma in 105 patients. We also found a prognostic significance in 41 glioblastoma multiforme (GBM) patients with the prevalence of nucleus HDGF predicts the short survival of GBM after surgery. To delineate the mitogenic role of HDGF in gliomagenesis, an adenoviral-expressed HDGF small interfering RNA (Ad-HDGF siRNA) was used to knock down the expression of nucleus HDGF. After knocking down the nuclear HDGF expression in human GBM cells, cell growth and cell invasion and induction on apoptosis by caspase-3 activation were significantly inhibited. We concluded that HDGF is a mitogenic growth factor in the progression of glioma and it can be a useful prognostic marker for GBM and therapeutic target for clinical management of glioma in the future. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5627. doi:1538-7445.AM2012-5627