Fig. 3: Functional validation of PPP2R2B in modulating response to HER2-targeted therapies.

a Representative images (n = 9) of soft agar assay with SKBR3 cells transduced with either the empty vector (Vector) or the vector containing PPP2R2B, and treated with the indicated concentration of lapatinib. Scale bar: 1.5 mm. b Quantification of soft agar assay performed with cells from a and treated with the indicated concentrations of lapatinib. Data are expressed as means ± s.d. of technical triplicates and representative of three independent overexpression experiments. The indicated IC50s were calculated with the three independent experiments and the P value was determined by comparing the IC50s from Vector to the ones from PPP2R2B, with two-tailed Student’s t-test. c Representative western blot analysis (n = 2) with cells from a treated with lapatinib at 40 nM. d PPP2R2B-PP2A in vitro phosphatase assay (n = 1) using anti-FLAG immunoprecipitates (IP) from SKBR3 expressing empty vector (Vector), N-FLAG-PPP2R2B, or the C-FLAG-PPP2R2B, incubated with whole cell lysate from SKBR3. e Soft agar assay with BT474 transduced with shNC or shRNAs against PPP2R2B and treated with the indicated concentrations of lapatinib. Data are expressed as mean ± s.d. of two independent experiments performed in triplicate (n = 6). P values were determined by two-way ANOVA. f Representative western blot analysis (n = 2) with cells from d treated with lapatinib (Lap) at 10 nM. Effectors downstream of mTOR were highlighted in red in a, d, and e.