Cholangiocarcinoma (CCA) is a difficult-to-treat cancer, with limited therapeutic options and surgery being the only curative treatment. Standard chemotherapy involves gemcitabine-based therapies combined with cisplatin, oxaliplatin, capecitabine, or 5-FU with a dismal prognosis for most patients. Receptor tyrosine kinases (RTKs) are aberrantly expressed in CCAs encompassing potential therapeutic opportunity. Hence, 112 RTK inhibitors were screened in KKU-M213 cells, and ceritinib, an approved targeted therapy for ALK-fusion gene driven cancers, was the most potent candidate. Ceritinib’s cytotoxicity in CCA was assessed using MTT and clonogenic assays, along with immunofluorescence, western blot, and qRT-PCR techniques to analyze gene expression and signaling changes. Furthermore, the drug interaction relationship between ceritinib and cisplatin was determined using a ZIP synergy score. Additionally, spheroid and xenograft models were employed to investigate the efficacy of ceritinib in vivo. Our study revealed that ceritinib effectively killed CCA cells at clinically relevant plasma concentrations, irrespective of ALK expression or mutation status. Ceritinib modulated multiple signaling pathways leading to the inhibition of the PI3K/Akt/mTOR pathway and activated both apoptosis and autophagy. Additionally, ceritinib and cisplatin synergistically reduced CCA cell viability. Our data show ceritinib as an effective treatment of CCA, which could be potentially explored in the other cancer types without ALK mutations.

DNA is frequently damaged by genotoxic stresses such as ionizing radiation, reactive oxygen species, and nitrogen species. DNA damage is a key contributor to cancer initiation and progression, and thus the precise and timely repair of these harmful lesions is required. Recent studies revealed transcription as a source of genome instability, and transcription-coupled DNA damage has been a focus in cancer research. Impaired mRNA export is closely related to DNA damage through R-loop formation. The molecular machineries of transcription-coupled DNA damage have been extensively analyzed in Saccharomyces cerevisiae. However, the molecular basis of these phenomena in higher eukaryotes remains elusive. In this review, we focus on the relationship between deregulated mRNA export through the transcription-export-2 (TREX-2) complex and cancer development. Particularly, the expression of germinal center-associated nuclear protein (GANP), a molecular scaffold in the TREX-2 complex, is highly associated with tumorigenesis in mice and humans. Although the deregulated expression of other components in the TREX-2 complex might affect cancer development, we have directly demonstrated the significance of GANP in tumorigenesis using genetically modified mice. Additionally, we describe recent evidence for medical applications demonstrating that the downregulation of the other components may be a good candidate for a chemotherapeutic target in terms of reducing the side effects.

Cholangiocarcinoma (CCA) is an uncommon adenocarcinoma of the bile duct epithelial. There is no standard regimen yet for patients with adequate performance status. Therefore, effective agents are necessary. Recently, protein-bound polysaccharide K (PSK) has shown a great anticancer potential. L. polychrous is a Thai local edible mushroom that traditionally used as a folk medicine for treatments of fever and inflammation. This study aimed to identify the PSK from hot water extract of L. polychrous and examine the anticancer activity against a CCA cell line KKU-213A. The PSK were quantified by ELISA and characterized using SDS-PAGE, glycoprotein staining kit, and western blot analysis. The antioxidant activity was assessed by DPPH assay. Cytotoxic effect against KKU-213A was assessed by MTT assay. Apoptosis and cell cycle were analyzed by flow cytometry. The highest PSK levels were found in L. polychrous extract compared with the other 14 mushroom species which purified PSK is approximately 70 kDa of glycoprotein. The hot water extract of L. polychrous showed strong antioxidant activity. The cell viability of KKU-213A cells was significantly inhibited with L. polychrous extract at an IC50 value of 3.31 ± 0.09 mg/mL. In addition, the induction of cell cycle arrest at S and G2/M phases was observed together with induction of apoptosis, and mitochondrial membrane dysfunction in concentration-dependent manner. Hence the L. polychrous extract is the great source of PSK with strong antioxidant activity and exhibits anti-CCA effects through cell cycle arrest and apoptotic induction. HIGHLIGHTS Lentinus polychrous, a Thai local edible mushroom, is the good source of PSK and powerful antioxidant activity. The hot water extract of L. polychrous suppresses cell viability, induces apoptosis, cell cycle arrest, and mitochondrial dysfunction in CCA cell line. The anticancer effects of L. polychrous extract against CCA cells makes it a potential agent for CCA treatment. GRAPHICAL ABSTRACT

Cholangiocarcinoma (CCA) is a highly aggressive malignancy with limited treatment options and frequent chemoresistance. Peanut hairy root culture crude extract (PCE) has previously demonstrated selective cytotoxicity toward CCA cells. Here, we investigated the combinatorial effects of PCE with standard chemotherapeutic agents on CCA cell lines. In KKU-213 A cells, PCE exhibited antagonistic and additive interactions with gemcitabine (Gem) and 5-fluorouracil (5-FU), respectively. In contrast, both combinations showed synergistic effects in KKU-100 cells, with the strongest synergy observed for PCE and Gem. Further investigation in KKU-100 cells revealed that the PCE-Gem combination significantly induced apoptosis, as evidenced by increased levels of cleaved caspase-8, caspase-3, and PARP, without affecting cell cycle progression. Notably, no cytotoxic effect was observed in normal human fibroblasts (HSF-hTERT). In a nude mouse xenograft model, co-treatment with PCE and Gem significantly inhibited tumor growth and reduced Ki-67 expression compared to monotherapies. These findings suggest that PCE enhances the anticancer efficacy of Gem in CCA and may serve as a supportive combinatorial strategy.

Cholangiocarcinoma (CCA) is a highly prevalent malignancy in Southeast Asia and is strongly associated with chronic biliary inflammation. Preventive strate

DNA is frequently damaged by genotoxic stresses such as ionizing radiation, reactive oxygen species, and nitrogen species. DNA damage is a key contributor to cancer initiation and progression, and thus the precise and timely repair of these harmful lesions is required. Recent studies revealed transcription as a source of genome instability, and transcription-coupled DNA damage has been a focus in cancer research. Impaired mRNA export is closely related to DNA damage through R-loop formation. The molecular machineries of transcription-coupled DNA damage have been extensively analyzed in Saccharomyces cerevisiae. However, the molecular basis of these phenomena in higher eukaryotes remains elusive. In this review, we focus on the relationship between deregulated mRNA export, especially through the transcription-export-2 (TREX-2) complex, and cancer development. The expression of GANP, a key molecule in the TREX-2 complex, is highly associated with tumorigenesis in mouse and human. Additionally, we describe recent evidence for medical application that downregulation of the other components may be a good candidate for chemotherapeutic target in terms of reducing the side effects, although the involvement of R-loop is still ambiguous.