OBJECTIVETo study the role of inhibition FAK expression by FAK siRNA in liver cancer cell (MHCC97-H) adhesion, invasion and cytoskeleton rearrangement.

METHODSFAK siRNA was transfected into MHCC97-H cell by Lipofectamine 2000; then, FAK expression was detected by Western blot analysis. The change of cell adhesive and invasive ability after RNAi was checked by cell adhesive assay and cell invasive assay respectively. Meanwhile, matrix metalloproteinase-2 secretion was checked by gelatin zymography. Cytoskeleton rearrangement labeled by immunofluorescence antibody was examined by confocal laser scanning microscope.

RESULTSFAK expression in MHCC97-H cell was obviously inhibited by specific FAK siRNA; However, it was not inhibited by negative siRNA. Adhesion rate between MHCC97-H cell and extracellular matrix decreased from 57.3% to 35.8% after RNA interference (P < 0.05). Compared with untreated group, the number of cell penetrating matrigel also decreased from 31.3 +/- 2.6 to 14.5 +/- 3.1 after transfection (P < 0.05). Besides, matrix metalloproteinase-2 secretion was significantly reduced for FAK expression inhibited by FAK siRNA. FAK inhibition influenced Vinculin rearrangement, blocked the formation of lamellipodium, delayed the time of focal adhesion formation.

CONCLUSIONDown-regulation the expression of FAK can reduce adhesive rate and invasive number of MHCC97-H cell by influencing cytoskeleton rearrangement and decreasing matrix metalloproteinase-2 secretion.