H19 and cholangiocarcinoma: To validate the expression patterns of HULC and H19 under oxidative stress, we then used three human CCA cell lines, QBC939, SK-cha-1, and RBE, for short-term or long-term oxide incubation using H2O2 and glucose as described in previous studies [34] and measured the expression levels of HULC and H19 by qPCR.