Blockade of Aquaporin 1 Inhibits Proliferation, Motility, and Metastatic Potential of Mesothelioma In Vitro but not in an In Vivo Model

Figure 2

Decreased AQP1 function reduces the rate of cell proliferation. (a) H226 cells treated with AqB050 show dose-dependent decrease in proliferation, . Error bars: SD. Analysed by ANOVA, , with Tukey’s post hoc analysis, (as indicated by ∗). (b) Primary cells treated with AqB050 show dose-dependent decrease in proliferation only in those populations where ≥20% of the MM population expressed AQP1 (designated “high”); high and low . Error bars: SEM, analysis by one-way ANOVA (high ; low ). (c) AQP1 siRNA treatment decreased AQP1 mRNA levels in primary MM cells and H226 cells. Decrease of AQP1 mRNA levels following siRNA knockdown was confirmed by RT-PCR. AQP1 mRNA was routinely decreased to 6–17% of the vehicle control levels. Shown is a representative example of primary MM cells. (d) AQP1 protein expression as assessed by immunohistochemistry (brown labeling) is preserved on the cell surface of primary MM cells treated with scrambled siRNA. (e) AQP1 protein expression as assessed by immunohistochemistry (brown labeling) is decreased on the cell surface of the same primary MM cells treated with AQP1 siRNA. (f) AQP1 siRNA treatment decreases proliferation of H226 and primary MM (H226: , one-way ANOVA , vector versus AQP1 siRNA ; primary cells: , one-way ANOVA , vector versus AQP1 siRNA ) with significance indicated by ∗. V: vector, S: scrambled, G: GAPDH, A: AQP1.