Figure 8

Phosphorylation of ERK1/2, FAK and AKT by over-expression of HSP70/MRJ is mediated by uPAR in HCT116 cells. (A) Cells were transfected with PRK5, or MRJ-PRK5, or HSP70-PRK5-flag or MRJ-PRK5 plus HSP70-PRK5-flag as shown in the figure. Forty-eight hours after transfection, cells were lysed and 60 μg of total protein from each sample was loaded on SDS-PAGE. Then, the protein levels of ERK1/2, p-ERK1/2, FAK, p-FAK and p-AKT were analyzed by Western blot. Tubulin was used as a loading control. The results shown are representative of three independent experiments. (B) The bands shown in (A) were scanned by densitometry using Image J software. The ratios of phopho-ERK vs ERK, phospho-FAK vs FAK and p-AKT were calculated. The ratios in MRJ plus HSP70-transfected cells were arbitrarily taken as 1.0 and values of all others relative to it were calculated accordingly. The histagram shows the mean ± SD, *P < 0.05: significantly different from the control, *P < 0.01: highly significantly different from the control.