STAT3 and intrahepatic cholangiocarcinoma: circGGNBP2 encodes a protein, GGNBP2‐184aa, that interacts with STAT3, phosphorylates the Tyr705 site of STAT3 and initiates transcription of STAT3 downstream target genes, ultimately leading to IL‐6/GGNBP2‐184aa/STAT3 initiation of a positive feedback loop that maintains constitutive activation of IL‐6/STAT3 signalling in intrahepatic cholangiocarcinoma cells, thereby promoting the progression of intrahepatic cholangiocarcinoma.48