Figure 6. Src-focal adhesion kinase (FAK) signalling regulates the expression and activation of c-Jun via AKT activation.

A. The protein levels of pAKT-S⁴⁷³, total AKT, p-c-Jun-S⁷³ and total c-Jun in the normal human foreskin keratinocytes (HFK) expressing pBabe (control), early passage and late passage HFK expressing HPV16 E6/E7 genes. B. Immunofluorescence detection of p-c-Jun-S⁷³ on the rafts. C. The relative mRNA levels of c-Jun and MMP14, and D. protein levels of total AKT, total c-Jun, p-c-Jun-S⁷³, MMP14 and total p63 after transient knockdown with scram (control) and total AKT siRNA in late passage E6/E7-HFK. E. The relative mRNA levels of c-Jun and MMP14, and F. protein levels of total c-Jun, MMP14 and β-actin after transient knockdown with scram (control) and two different c-Jun siRNA molecules in the late passage E6/E7-HFK. G. Protein levels of total FAK, total Src, pAKT-S⁴⁷³, total AKT, p-c-Jun-S⁷³ and total c-Jun after transient knockdown by Scram (control), FAK or Src siRNA molecules in the late passage E6/E7-HFK. H. Immunofluorescence detections of p-c-Jun-S⁷³ and BrdU uptake on 3D-organotypic rafts established from the late passage population and treated with specific inhibitors of FAK (PF573228) and Src (dasatinib) activities. Rafts treated with DMSO served as control. The invasive incidents are indicated by arrows. I. Protein levels of total c-Jun, p-c-Jun-S⁷³ in early passage E6/E7-HFK expressing GFP, wild type-Src (Src-WT), constitutively active (Src-531) and kinase dead (Src-KD) constructs. β-actin served as loading control. Scale bars represent 100 μm. N = 3 independent experiments, mean ± SEM, *p < 0.05 compared to the respective controls, ^†p < 0.05 compared to the respective controls.