MAPK3 and neoplasm: These proteins were selected because they are crucial for the induction of tumor cell epithelial-mesenchymal transition (EMT)33 As shown in Fig. 2A–D, levels of p38 MAPKs were significantly increased in HepG2 treated with C1q for 1 h, and levels of ERK1/2 and JNK were slightly increased at 1 h and returned to baseline at 4 h.