Correlation analysis between VAV3 expression and compounds: half-maximal inhibitory concentration identifies erlotinib as a potential therapeutic compound. (A) Graph showing the correlation between VAV3 expression (two probes showed similar results, depicted for 218807_s_at) and erlotinib (left panel) or thapsigargin (right panel) logarithmic half-maximal inhibitory concentration (IC50) values across all cancer cell lines. Spearman’s correlation coefficient (SCC) and the corresponding P-values are shown. Red lines indicate trends, and insets show results for breast cancer cell lines only. (B) Graph showing the inhibitory effect of erlotinib on long-term estrogen-deprived MCF7 (MCF7-LTED) cells relative to parental MCF7 cells. (C) Top panels, Western blot analysis results for VAV3 (total), pT173 VAV3 and control tubulin α (TUBA) from MCF7 and MCF7-LTED cells in basal and erlotinib exposure conditions. Bottom panels, Western blot analysis results for pT173 VAV3 and control TUBA from MCF7 and MCF7-LTED cells with or without epidermal growth factor (EGF).