Figure 5

STING activity is sufficient for chemoresistance and contributes to drug tolerance and acquired resistance in vitro. (a) Immunoblot of lysates taken after 24 h of 5uM diABZI or DMSO treatment in MDA-MB-231 cells with the indicated antibodies. β-actin is shown as a loading control. Representative image from n = 3 independent experiments. (b) Proliferation of MDA-MB-231 cells in response to 24 h diABZI or DMSO pre-treatment followed by 72 h gemcitabine co-treatment. (c) IC₅₀ quantification of MDA-MB-231 dose–response curve (b). (d) Immunoblot of lysates taken after 24 h of 5uM diABZI or DMSO treatment in HCC38 (left) and HCC38^STING overexpressing cells (right) with the indicated antibodies. β-actin is shown as a loading control. Representative image from n = 3 independent experiments. (e) Proliferation of HCC38^STING overexpressing cells in response to 24 h diABZI or DMSO pre-treatment followed by 72 h gemcitabine co-treatment. (f) IC₅₀ quantification of HCC38^STING dose–response curve (e). (g,h) Crystal violet staining of MDA-MB-231 (g) and HCC38^STING overexpressing cells (h) after 9 d treatment with increasing concentrations of gemcitabine. Images are representative of n = 3 independent experiments with similar results. For (b,c,e,f), data represents n = 4 biologically independent samples. Error bars are mean ± s.d., and P values calculated using a two-sided t-test.