ATF3 and intrahepatic cholangiocarcinoma: Meanwhile, ICC sub-clusters presented a different pattern featuring JUN, JUNB, JUND, FOS, FOSB, GATA2, KLF6, MAFK, ATF3, and TFAP2A, the first 5 of which were enriched in AP-1 transcription factor family that may be related to epigenetic disruption and matrix formation39,40(Fig. 3e).