Anti-tumoral activity of native compound morelloflavone in glioma.

The aim of the study was to investigate the anti-tumoral activity of morelloflavone substances with different structures. We also studied the possible link between morelloflavone structure and its function. Various types of chromatographic techniques were used to isolate and screen morelloflavone substances from the extracts of gambogic tree trunk and the morelloflavone structures were identified by analytical techniques such as high resolution mass spectrometry and nuclear magnetism. Anti-tumoral activities of different compounds were investigated and the link between the antitumor activity and the structure of compound was exaimed. Our results showed that the isolated morelloflavone substances demonstrated a certain level of antitumor activity. The compound no. 1 had the strongest effect to inhibit glioma U87 and C6 cells followed by compound no. 2 while compound no. 5 was the weakest among them. We conducted a preliminary analysis on the structure-function relationship through the structure comparison and we concluded that the antitumor effects of morelloflavone substances with different structures were significantly different from each other. Thus, the glucose chain in C4 position of biflavone structure can enhance the antitumor activity of the compound in glioma cells. Additionally, the formation of intramolecular hydrogen bonds in biflavone compounds may also play a role in enhancing the antitumor activity and inhibition rate.