Figure 3. Resistance to TAM is positively associated with HMGB1 elevation. (A, B) CCK8 detection of the viability of MCF-7 cells cultured with CM from immortalized cells and CM from CAF-shGPR30 cells pretreated with G1 or TAM in the presence or absence of G15 for 24 h. *P < 0.05 vs control; ** P < 0.05 vs control; ctrl: MCF-7 cells cocultured with fresh phenol red-free medium. The viability of MCF-7 cancer cells was notably changed with the addition of (C) recombinant HMGB1, (D) anti-rHMGB1, and (E) LY294002. (*P < 0.05 vs control; ** P < 0.01 vs control; ctrl: MCF-7 cells cocultured with fresh phenol red-free medium supplemented with DMSO). All data were analyzed by the IC50 software, and repeated at least 3 times.