Metabolic Phenotyping Predicts Gemcitabine and Cisplatin Chemosensitivity in Patients With Cholangiocarcinoma.

Gemcitabine and cisplatin serve as appropriate treatments for patients with cholangiocarcinoma (CCA). Our previous study using histoculture drug response assay (HDRA), demonstrated individual response patterns to gemcitabine and cisplatin. The current study aimed to identify predictive biomarkers for gemcitabine and cisplatin sensitivity in tissues and sera from patients with CCA using metabolomics. Metabolic signatures of patients with CCA were correlated with their HDRA response patterns. The tissue metabolic signatures of patients with CCA revealed the inversion of the TCA cycle that is evident with increased levels of citrate and amino acid backbones as TCA cycle intermediates, and glucose which corresponds to cancer stem cell (CSC) properties. The protein expression levels of CSC markers were examined on tissues and showed the significantly inverse association with the responses of patients to cisplatin. Moreover, the elevation of ethanol level was observed in gemcitabine- and cisplatin-sensitive group. In serum, a lower level of glucose but a higher level of methylguanidine was observed in the gemcitabine-responders as non-invasive predictive biomarker for gemcitabine sensitivity. Collectively, our findings indicate that these metabolites may serve as the predictive biomarkers in clinical practice which not only predict the chemotherapy response in patients with CCA but also minimize the adverse effect from chemotherapy.

Upregulation of endothelial nitric oxide synthase (eNOS) and its upstream regulators in Opisthorchis viverrini associated cholangiocarcinoma and its clinical significance.

Endothelial nitric oxide synthase (eNOS) is an isoform of the enzyme nitric oxide synthase (NOS) which is constitutively expressed in endothelial cells and plays important roles in vasodilation. We previously reported the importance of eNOS activation in cholangiocarcinoma (CCA) tissues and cell lines. The present study aims to investigate the relative abundance of eNOS and phosphorylated eNOS (P-eNOS) and their upstream regulators VEGFR3, VEGFC, EphA3 and ephrin-A1, in the Opisthorchis viverrini (Ov)/N-nitrosodimethylamine (NDMA)-induced hamster CCA model and in human CCA by semiquantitative immunohistochemical analysis of the relevant tissues. Results from the hamster model suggested an increase in eNOS and P-eNOS and upstream regulators during CCA genesis. In human CCA, high immunohistochemical staining intensity of all investigated proteins was associated with the presence of metastasis. A pairwise analysis of the staining data for eNOS and its upstream regulators showed that a concurrent increase in eNOS/VEGFR3, eNOS/ephrin-A1, eNOS/VEGFC and eNOS/EphA3 was significantly associated with metastasis. An increase in eNOS/VEGFR3, eNOS/ephrin-A1 was also associated with non-papillary type CCA. Additionally, an increase in eNOS and P-eNOS was significantly correlated with a high micro-vessel level (P=0.04). Our results indicate that the development of CCA involves upregulation of eNOS and P-eNOS and their regulators. This may drive angiogenesis and metastasis in CCA.