Figure 3. A. mRNA levels of RAB5, RAB7 and RAB11 estimated by qRT-PCR was elevated in a highly metastatic cell line (OSCC1.2) established from a poorly differentiated and metastatic human oral cancer (stage: T4N2b) with vascular, lymphatic and perineural invasion, as well as in the SCC-25 cell line while low expression was seen in normal oral epithelial (NOE) cells established from normal human tongue tissue (*P < 0.05).

GAPDH was used as a reference gene. Y-axis corresponds to the relative quantification of transcript levels and X-axis represents the genes. B. Western blot analysis showing efficient down-regulation (> 90%) of endogenous Rab5, Rab7 and Rab11 proteins compared to control cells. GAPDH was used as an internal control. C. Invasion capacity using the Boyden chamber assay on control OSCC cells and their matched cells expressing siRNA targeting Rab5, Rab7 or Rab11. Bar graph represents the mean number of invaded cells (*P < 0.05). D. Cell migration, analyzed by the wound healing assay during 24 h, revealed that OSCC cell migration into the scratched area was inhibited when Rab expression was inhibited by siRNA. Bar graph represents the mean ± SD of five independent experiments, and representative images of the wound captured at different time points are shown.