Inhibition of KLK4 increased paclitaxel sensitivity.

<p>WST-1 assay shows cell survival of KLK4-1, KLK4-2, KLK4-3, Vec-1, Vec-2 clones and native SKOV-3 MCAs after paclitaxel (<b>A</b>) treatment in 3D-suspension. <b>B.</b> Left panel, representative images of KLK4-1 MCAs on day 4 with mouse IgG and a functional KLK4 blocking antibody, PBS as a control and KLK4 selective inhibitor SFTI-FCQR (SFTI) as indicated. Right panel, representative images of OVCA432 MCAs on day 4 with PBS as a control and KLK4 selective inhibitor SFTI-FCQR (SFTI) or aprotinin as indicated. Scale bars, 200 µm. <b>C.</b> Cell survival determined by WST-1 assay after treatment with paclitaxel (Pac) on 3D-suspension cultured KLK4-1 clone and OVCA432 cells +/−1 µM SFTI or 5 µM aprotinin (Aprot). Experiments in panels <b>A</b> and <b>C</b> were repeated 3 times in triplicate, bars represent Mean ± SEM. Statistical significance indicated as *P<0.05, **P<0.01.