Endogenous expression of Tβ10 in CCA tissue specimens and cell lines. To investigate the expression of Tβ10 in CCA, 10 pairs of CCA surgical specimens were collected from the operating room under an approved research protocol. (A) Tβ10 mRNA levels of the primary tumor and metastatic tumor of each CCA case were analyzed by using real time RT-PCR. Tβ10 mRNA levels were significantly lower in the metastatic site than that in the primary tumor tissue (*P<0.05; n=10). (B) Tβ10 protein levels of a representative CCA case of paired tissues were determined by immunohistochemistry. (C) Tβ10 mRNA levels were also examined in 5 CCA cell lines (KKU-M055, KKU-M156, KKU-M213, KKU-M214 and KKU-100) by real time RT-PCR. (D) Tβ10 protein levels were determined by immunocytochemistry in three CCA cell lines (KKU-M213, KKU-M214 and KKU-100).