Fig. 2. Higher levels of MED12 and CARM1 correlate with better response to chemotherapy drugs in cell line models and clinical cohorts.

(A) KM curves stratified by MED12 mRNA levels depicting the probability of RFS in untreated, endocrine therapy–treated, or chemotherapy-treated breast cancer patients. Patient samples were divided into MED12^high and MED12^low groups based on the median of the expression level of MED12. Affymetrix gene ID 214275_at was used to plot the survival curves of MED12 using data sets from Gene Expression Omnibus (GEO) (Affymetrix HG-U133A and HGU-133+2 microarrays), European Genome-Phenome Archive (EGA), and The Cancer Genome Atlas (TCGA). HR, hazard ratio. (B and C) High levels of CARM1 and MED12 proteins correlate with better survival after 5-fluorouracil (5-FU) or doxorubicin treatment in breast cancer patients with 100-month follow-up (n = 254). KM estimates of DFS and OS of human patients according to the expression levels of CARM1 (n = 254) or CARM1/MED12 (n = 154). Comparison was made between groups with high or low levels of CARM1 alone or high or low levels of CARM1 and MED12. P value refers to two-sided log-rank tests. (D) Cell viability analyses of three paired CARM1^WT and CARM1^KO breast cancer cell lines after incubating with 1 μM 5-FU, doxorubicin, or floxuridine for 72 hours. Cell viability was determined by MTT assays. Quantitative data are presented as averages ± SD. Student’s t test was used for statistical analysis. *P < 0.05; **P < 0.01. (E) Western blotting shows the knockdown of MED12 in both CARM1^WT and CARM1^KO MDA-MB-231 cells. (F) Cell viability analyses of MDA-MB-231 CARM1^WT shCtrl, MDA-MB-231 CARM1^WT shMED12, MDA-MB-231 CARM1^KO shCtrl, and MDA-MB-231 CARM1^KO shMED12 cells after treatment with 5-FU or doxorubicin for 72 hours. Quantitative data are presented as averages ± SD. Student’s t test was used for statistical analysis. *P < 0.05; **P < 0.01. (G) Western blotting shows the knockdown of MED12 in both CARM1^WT and CARM1^KO MCF7 cells. (H) Cell viability analyses of MCF7 CARM1^WT shCtrl, MCF7 CARM1^WT shMED12,MCF7 CARM1^KO shCtrl, and MCF7 CARM1^KO shMED12 cells after treatment with 5-FU or doxorubicin for 72 hours. Quantitative data are presented as averages ± SD. Student’s t test was used for statistical analysis. *P < 0.05.