MicroRNAs and cholangiocarcinoma: elucidating the effects of tiny giants

SRY-Box Transcription Factor 9 (SOX9) Affects the Proliferation, Invasion and Epithelial to Mesenchymal Transition (EMT) of Intrahepatic Cholangiocarcinoma by Regulating Transforming Growth Factor β (TGFβ)/Smad Signaling

Intrahepatic cholangiocarcinoma (ICC) develops rapidly with a high malignancy. SOX9 expression is increased in several tumors. However, its expression and role in intrahepatic cholangiocarcinoma have not yet been elucidated. Real time PCR and Western blot were done to assess SOX9 expression in tumor tissues and adjacent tissues of ICC. ICC cell line QBC939 cells were separated into control group, SOX9 overexpression group and SOX9 siRNA group followed by analysis of cell survival by MTT assay, cell migration by cell scratch assay, cell invasion by transwell chamber, E-cadherin and Vimentin level by western blot, TGFβ/Smad signaling protein level by real time PCR. SOX9 level in tumor tissues was significantly increased compared to adjacent tissues (P < 0.05) and it was associated with TNM stage, tissue type and metastasis, and survival time (P < 0.05). Transfection of pcDNA3.1-SOX9 upregulated SOX9, promoted cell proliferation, migration and invasion, downregulated E-cadherin, upregulated Vimentin, TGF-β1 and Smad4 (P < 0.05). SOX9 siRNA transfection into QBC939 cells could significantly reverse the above mentioned changes (P < 0.05). SOX9 level is increased in intrahepatic cholangiocarcinoma and targeting SOX9 can inhibit cell migration and invasion, and EMT via regulating TGFβ/Smad signaling.

Inflammation and Progression of Cholangiocarcinoma: Role of Angiogenic and Lymphangiogenic Mechanisms

Cholangiocarcinoma (CCA), or cancer of the biliary epithelium is a relatively rare but aggressive form of biliary duct cancer which has a 5-year survival rate post metastasis of 2%. Although a number of risk factors are established for CCA growth and progression, a careful evaluation of the existing literature on CCA reveals that an inflammatory environment near the biliary tree is the most common causal link between the risk factors and the development of CCA. The fact that inflammation predisposes affected individuals to CCA is further bolstered by multiple observations where the presence and maintenance of an inflammatory microenvironment at the site of the primary tumor plays a significant role in the development and metastasis of CCA. In addition, mechanisms activating the tumor vasculature and enhancing angiogenesis and lymphangiogenesis significantly contribute to CCA aggressiveness and metastasis. This review aims to address the role of an inflammatory microenvironment-CCA crosstalk and will present the basic concepts, observations, and current perspectives from recent research studies in the field of tumor stroma of CCA.

Lnc-LFAR1 affects intrahepatic cholangiocarcinoma proliferation, invasion, and EMT by regulating the TGFβ/Smad signaling pathway

Intrahepatic cholangiocarcinoma (ICC) has had an increasing incidence in recent years. It exhibits high recurrence and metastasis rates, so it is a global health problem. LncRNAs have long been thought to have a role in regulating tumorigenesis and tumor progression and in playing a carcinogenic or tumor suppressor role in malignant cells. Lnc-LFAR1 is enriched in liver tissue, but its role and mechanism in ICC have not been elucidated. ICC cell line QBC939 cells were randomly divided into 3 groups, including a control group, an lnc-LFAR1 overexpression group, and an lnc-LFAR1 siRNA group, the cells of which were transfected with pcDNA3.1-LFAR1 plasmid and lnc-LFAR1 siRNA, respectively. Real-time PCR was used to quantify lnc-LFAR1 expression. A tetrazolium salt (MTT) colorimetric assay was adopted to assess cell viability. A cell scratch assay was selected to assess cell migration. A transwell chamber assay was used to test cell invasion. E-cadherin and vimentin expressions were detected using Western blot. The TGFβ/Smad signaling pathway was measured using real-time PCR. The transfection of pcDNA3.1-LFAR1 significantly increased the expression of lnc-LFAR1, promoted cell proliferation, facilitated cell migration and invasion, reduced E-cadherin levels, enhanced vimentin expression, upregulated TGF-β1 and Smad2 and Smad4 expressions (P < 0.05). Lnc-LFAR1 siRNA transfection clearly downregulated lnc-LFAR1 expression, inhibited cell proliferation, suppressed cell migration and invasion, increased E-cadherin expression, and decreased vimentin, TGF-β1, Smad2, and Smad4 levels (P < 0.05). Targeting lnc-LFAR1 can inhibit cell proliferation, migration, invasion, and EMT by regulating the TGFβ/Smad pathway to affect the occurrence and development of cholangiocarcinoma.