[Primary study of vasculogenic mimicry induced by hypoxia in epithelial ovarian carcinoma]

To explore possibility of vasculogenic mimicry induced by hypoxia and the inhibitive effect by sirolimus in epithelial ovarian carcinoma in vitro.

Based on three-dimensional cell culture system developed by Matrigel, ovarian cell lines SKOV3 and ES2 were induced under conditions of hypoxia, hypoxia added with sirolimus and no-hypoxia, respectively. Potential formation of tumor channels and their characterization of network were observed by light microscopy and scanning electronic microscopy. Relative hypoxia-inducible factor (HIF) 1alpha mRNA expression was detected by RT-PCR simultaneously.

The micrograph showed both SKOV3 and ES2 cells appeared expanded and re-shaped, then formed blood vessel-like structures such as cavity, channel, branch and network. These capabilities of cells were inhibited by sirolimus and no-hypoxia. The levels of HIF-1alpha mRNA expression of SKOV3 and ES2 were 0.801 +/- 0.034 and 0.736 +/- 0.059 under hypoxia, which were significantly higher than under hypoxia added with sirolimus (0.025 +/- 0.007, 0.231 +/- 0.035; P < 0.01, P < 0.05), and those under no-hypoxia (0.010 +/- 0.004, 0.011 +/- 0.002; both P < 0.01).

Hypoxia plays a key role in development of vasculogenic mimicry in epithelial ovarian carcinoma. Sirolimus can inhibit vasculogenic mimicry effectively by blocking HIF-1alpha at transcription level.