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 during melanoma carcinogenesis remains unclear. In this study, adding exogenous HDGF stimulated the invasion and colonies formation of B16-F10 melanoma cells. Adenovirus vectors encoding HDGF and HDGF-RNAi were generated and characterized to up- and down-regulated HDGF expression in B16-F10 melanoma cells. It was found that HDGF overexpression stimulated the proliferation, invasiveness, anchorage-independent growth of B16-F10 melanoma cells whereas HDGF knockdown exerted opposite effects. In lung-metastasis model, intravenous injection of HDGF-overexpressing melanoma cells resulted in increased metastasis while HDGF-downregulated melanoma cells caused decreased metastasis. Similarly, in primary melanoma model, subcutaneous injection of HDGF-overexpressing melanoma cells enhanced while HDGF-downregulated melanoma cells reduced the tumor burden in mice. Histological analysis revealed increased tumor proliferation and neovascularization with concomitant reduction of apoptosis in HDGF-overexpressing melanoma. Moreover, HDGF-overexpressing melanoma also exhibited enhanced propensity to metastasize from the primary tumors to lymph node and lung. Finally, it was found that HDGF overexpression increased nuclear factor kappa B (NF£eB) activities and Akt phosphorylation up and down stream alternation like PI3K, PTEN, I£eB and it¡¦s subunit IKK£\, IKK£], IKK£^ in melanoma cells. It also found that HDGF overexpression influenced MITF and HIF1£\ in melanoma after gene delivery. HDGF also altered EMT changes like E,N-cadherin, vimentin, and £],£^-catenin. The present study provides conclusive evidence that HDGF upregulation promotes the growth and metastasis of melanoma by promoting the survival and vascularization. Besides, HDGF knockdown may constitute a novel strategy for melanoma control.
Identifer | oai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0814108-003244 |
Date | 14 August 2008 |
Creators | Kuo, Lai-Hsin |
Contributors | Wen-Chun Hung, Hurng-Wern Huang, Ming-Hong Tai |
Publisher | NSYSU |
Source Sets | NSYSU Electronic Thesis and Dissertation Archive |
Language | English |
Detected Language | English |
Type | text |
Format | application/pdf |
Source | http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0814108-003244 |
Rights | withheld, Copyright information available at source archive |
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