Fig. 7

CM1 significantly enhanced cell invasion accompanied by increments of MMP-9 upregulation and N-cadherin cleavage. Briefly, NPC cells were cultured with and without PMA for 8 h, then PMA-containing medium was completely removed and replaced with completed medium for 24 h. The CM was collected and referred to as CM1 or C1. a CM1 induced NPC cell invasion. The invasive capability of CM1-treated NPC cells was investigated. CM1 was introduced into the outer well of NPC-cell–seeded Boyden chambers for 24 h. The invasive cells at the lower surface of the membrane were fixed, stained, photographed and counted. Data are mean±SEM. *p<0.05, N = 3. b CM1 reduced the level of N-cad. NPC cells were exposed to CM1 or C1 for 24 h, then cell lysates underwent western blot analysis. c CM1 upregulated MMP-9. NPC cells were treated with CM1 or C1 for 24 h, the CM was collected and referred to as CM2 or C2, respectively. The level of MMP-9 in CM1/CM2 was examined by gelatin zymography. Data are mean±SEM. N = 3, ^*P<0.05. d Blockade of intracellular cleavage of N-cadherin decreased CM1-mediatedMMP-9 expression. NPC cells were pre-treated with γI for 2 h and co-incubated with CM1 for 24 h, then cell lysates and CM underwent western blot analysis and gelatin zymography