Fig. 2

IMPDH2 levels influence response to doxorubicin. (A) Representative immunoblot for IMPDH2 in MDA-MB-231 (left) and 4T1 (right) cells transduced with two independent shIMPDH2 constructs (shI2), an IMPDH2 ectopic expression vector (I2OE), or their corresponding control vector. Actin is used as a loading control. Membranes were cut prior to hybridization with antibodies. Doxorubicin survival curve of MDA-MB-231 (n = 8) (B) or 4T1 (n = 3) (C) cells manipulated as in (A). Data is average −/+ std dev of 3 independent experiments. Doxorubicin survival curve of MDA-MB-231 naïve and DoxoR cells (D) or 4T1 naïve and M-DoxoR (E). Data is average −/+ std dev of 3 independent experiments. (F) Relative levels of IMPDH2 mRNA (left) and protein (right) in MDA-MB-231 naive and DoxoR. Data is average −/+ std dev of triplicates from 3 independent experiments (G) Relative levels of Impdh2 mRNA (left) and protein (right) in 4T1 naive and M-DoxoR. Data is average −/+ std dev of triplicates from 3 independent experiments. Statistics by unpaired Student’s t-test or by nonlinear fit regression model for IC₅₀ comparisons. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001.