Figure 5. Inhibition of FGFR2 reduces the CD44+/hi fraction and prevents colocalization of FGFR2 with CD44 in vivo.

A–B. FGFR2 kinase inhibitor PD173074 (A) and FGFR2-blocking neutralizing antibody (NAB) (B) significantly reduced the fraction of CD44^hi/++ potential GCSCs. C. PD173074 reduced p-FGFR2, p-ERK levels, and CD44 levels. D. PD173074 and FGFR NAB blocked CD44 colocalization with phospho-FGFR2 (p-FGFR2). Strong colocalization of bright total FGFR2 (denoted FGFR2) with CD44 was prevented by both FGFR2 inhibition methods prior to FGF7 treatment. P-FGFR2 confined to mostly periplasmic sites as a punctate form. The p-FGFR2 association with CD44 was prevented by FGFR2 inhibition.