Fig. 1.

Detection of early apoptotic events in floating human EOC cells as a function of the αvβ3 TMD conformational activation state. (A) EOC αvβ3 cell transfectant model. Integrin αvβ3 TMD variants were generated by exchanging the complete TMDs of the αv‐ and the β3‐subunit by the strongly dimerizing TMD of GpA (TMD‐GpA), resulting in a low affinity αvβ3 receptor lacking signaling capability. In addition, we point‐mutated the dimerization motif within GpA, GxxxG, to GxxxI, known to abrogate TMD association, conferring high‐affinity and constitutively active signaling competence (TMD‐GpA‐I; published in ref. [32]). (B) Human EOC cell transfectants were cultured in suspension for 48 h in ascites or DMEM and subjected to Annexin‐Fluos V/PI apoptosis assays in order to discriminate vital, apoptotic, and necrotic cell fractions. (C) Cell transfectants suspended for 30 h either in ascites or in DMEM were treated for another 18 h by cisplatin. Data are given for each cell fraction in % as mean values ± SD from 3 independent experiments. Significance was tested by two‐way ANOVA with post hoc Bonferroni t‐test. Significance is indicated by *P < 0.050, **P < 0.010, and ***P < 0.001 (n. s., not significant).