Finally, Xiao et al. provided evidence that the circular RNA Circ_0000591, served as endogenous RNA for miR-326 to promote the progression of CCA via the TLR4/MyD88/NF-κB/IL6 axis, enhancing our knowledge of potential molecular mechanisms involved in the malignant progression of CCA [176]. This evidence concerns the gene TLR4 and cholangiocarcinoma.