Figure 5: Co-inhibition of DGKA and PRKCA in irradiated fibroblasts.

(a) Partial correlation network of DGKA-associated proteins in fibroblasts. Data are based on correlations of relative protein signals (unirradiated versus irradiated) in seven patient fibroblasts. Line thickness indicates the strength of correlation, dotted lines depict inverse correlation (b) Effect of inhibitors of DGKA (R59949) and PRKCA (Gö6976) on cell growth of fibroblasts from fibrosis or non-fibrosis patients exposed to ionizing radiation at various dose combinations. Data show cell growth determined in quadruplicates after 96h drug treatment with radiation applied after 48 h. Cell growth was measured by calcein fluorescence assay. (c) Additive or synergistic drug effects from b were calculated with the Bliss independence model comparing the expected (additive) effects with the observed effects. Scale bar depicts the observed viability differences in comparison to the expected additive effects as blue (synergistic growth suppression) to red (synergistic growth increase). (d,e) Impact of R59949 (5.0 μM) and Gö6976 (0.5 μM) on collagen synthesis in NHDF measured by COL1A1 mRNA expression (d) or hydroxyproline release (e). Cells were pre-treated with drugs for 48 h and analysed an additional 48 h after exposure to radiation or TGFB1 (4 ng ml⁻¹) with concurrent drug treatment. Dots show mean values from duplicate (d,e) or quadruplicate (c) experiments for each fibroblast, bars depict mean±s.e.m. in each group. *P<0.05, **P<0.01, Student’s t-test.