Linobiflavonoid inhibits human lung adenocarcinoma A549 cells: effect on tubulin protein.

The antitumor bioactivities of linobiflavonoid were studied through evaluating its in vitro cytotoxicity against several cell lines (A549, H1975, SMMC-7721, HEP-2 and Vero cells), with the aid of 3-(4,5)-dimethylthiazoly1)-3,5-diphenytetrazolium bromide (MTT) assay. It was found that linobiflavonoid shows more notable inhibiting activity against A549 cells, with IC50 value of 4.67 μM. Furthermore, western blot analysis revealed that linobiflavonoid is able to increase the expression of β-tubulin, whereas not α-tubulin. In virtuale simulations indicated that linobiflavonoid specifically interacts with the binding pocket which is located at the top of β-tubulin, due to the presence of strong hydrophobic effects between the core templates and the hydrophobic surface of the tubulin protein (TB) binding site. The binding energy (E inter ) was calculated to be -140.47 kcal/mol. Results above suggest that linobiflavonoid possesses anti-A549 properties relating to β-tubulin depolymerization inhibition.