Dysregulation of microRNA in cholangiocarcinoma identified through a meta-analysis of microRNA profiling

Small but mighty: How microRNAs drive the deadly progression of cholangiocarcinoma

Cholangiocarcinoma, also referred to as CCA, is a highly complex epithelial malignancy that can impact various organs and regions of the body, including the perihilar, intrahepatic, and distal organs. This cancer is characterized by the malignant growth of the epithelial lining in the bile ducts, which spans the entire biliary tree and is accountable for disease progression. The current state of affairs concerning CCA is concerning, with poor prognoses, high recurrence rates, and dismal long-term survival rates significantly burden healthcare facilities worldwide. Studies have identified numerous signaling pathways and molecules involved in the development and progression of CCA, including microRNAs, an important class of non-coding RNAs that have the ability to modulate these cellular signaling pathways significantly. In addition, microRNAs may serve as an innovative target for developing novel therapeutic approaches for CCA. In this review, we explore the underlying mechanisms and signaling pathways implicated in the initiation and progression of CCA, focusing on the future direction of utilizing microRNAs as a promising treatment option for this challenging malignancy.

LncRNA FALEC increases the proliferation, migration and drug resistance of cholangiocarcinoma through competitive regulation of miR-20a-5p/SHOC2 axis

BACKGROUND

LncRNA is an important regulatory factor in the human genome. We aim to explore the roles of LncFALEC and miR-20a-5p/SHOC2 axis on the proliferation, migration, and Fluorouracil (5-FU) resistance of cholangiocarcinoma (CCA).

METHODS

In this study, the expression of FALEC and miR-20a-5p in CCA tissues and cell lines (HuCCT1, QBC939, and Huh-28) was detected by RT-qPCR. The FALEC in 5-FU-resistant CCA cell lines (QBC939-R, Huh-28-R) was knocked down to evaluate its effects on cell proliferation, migration, invasion, and drug resistance.

RESULTS

Our analysis showed that compared with the adjacent non-tumor tissues, FALEC was significantly higher in the CCA tissues and even higher in the samples from 5-FU-resistant patients. Knockdown FALEC increased the sensitivity of 5-FU and decreased migration and invasion of CCA cells. Dual luciferase reporter confirmed that FALEC sponges miR-20a-5p and down-regulated its expression. Moreover, SHOC2 leucine-rich repeat scaffold protein (SHOC2) was the target gene of miR-20a-5p. We found overexpression of FALEC (FALEC-OE) increased resistance of CCA cells to 5-FU significantly, which might contribute to increased SHOC2 expression and activation of the ERK1/2 signaling pathway.

CONCLUSIONS

In summary, our study revealed that down-regulation of FALEC could inhibit the proliferation, migration, and invasion of CCA cells in vitro by regulating the miR-20a-5p/SHOC2 axis and participating in 5-FU resistance by mediating the ERK1/2 signaling pathway.

The interplay of signaling pathways with miRNAs in cholangiocarcinoma pathogenicity and targeted therapy

Cholangiocarcinoma (CCA), the second most frequent liver cancer after hepatocellular carcinoma, has been rising worldwide in recent epidemiological research. This neoplasia's pathogenesis is poorly understood. Yet, recent advances have illuminated the molecular processes of cholangiocyte malignancy and growth. Late diagnosis, ineffective therapy, and resistance to standard treatments contribute to this malignancy's poor prognosis. So, to develop efficient preventative and therapy methods, the molecular pathways that cause this cancer must be better understood. MicroRNAs (miRNAs) are non-coding ribonucleic acids (ncRNAs) that influence gene expression. Biliary carcinogenesis involves abnormally expressed miRNAs that act as oncogenes or tumor suppressors (TSs). The miRNAs regulate multiple gene networks and are involved in cancer hallmarks like reprogramming of cellular metabolism, sustained proliferative signaling, evasion of growth suppressors, replicative immortality, induction/access to the vasculature, activation of invasion and metastasis, and avoidance of immune destruction. In addition, numerous ongoing clinical trials are demonstrating the efficacy of therapeutic strategies based on miRNAs as powerful anticancer agents. Here, we will update the research on CCA-related miRNAs and explain their regulation involved in the molecular pathophysiology of this malignancy. Eventually, we will disclose their potential as clinical biomarkers and therapeutic tools in CCA.

Emerging Role of microRNA Dysregulation in Diagnosis and Prognosis of Extrahepatic Cholangiocarcinoma

Extrahepatic cholangiocarcinomas, also called bile duct carcinomas, represent a special entity in gastrointestinal tumors, and histological specimens of the tumors are often difficult to obtain. A special feature of these tumors is the strong neovascularization, which can often be seen in the endoluminal endoscopic procedure called cholangioscopy, performed alone or in combination with laserscanning techniques. The additional analysis of microRNA expression profiles associated with inflammation and neovascularization in bile duct tumors or just the bile duct fluid of these patients could be of enormous additional importance. In particular, the dysregulation of microRNA in these cholangiocarcinomas (CCA) was previously reported to affect epigenetics (reported for miR-148, miR-152), inflammation (determined for miR-200, miR-125, and miR-605), and chemoresistance (miR-200b, 204) in patients with cholangiocarcinoma. More importantly, in the context of malignant neovascularization, well-defined microRNAs including miR-141, miR-181, miR-191, and miR-200b have been found to be dysregulated in cholangiocarcinoma and have been associated with an increased proliferation and vascularization in CCA. Thus, a panel of these microRNA molecules together with the clinical aspects of these tumors might facilitate tumor diagnosis and early treatment. To our knowledge, this is the first review that outlines the unique potential of combining macroscopic findings from cholangioscopy with microRNA expression.

Exosome-transmitted miR-3124-5p promotes cholangiocarcinoma development via targeting GDF11

Objective

Cholangiocarcinoma (CHOL) is a deadly cancer worldwide with limited available therapies. The aim of this study was to investigate key exosomal miRNAs and their functions in CHOL development.

Methods

Serum exosomes were isolated from patients with CHOL and healthy controls, followed by miRNA sequencing for identifying differentially expressed miRNAs (DEMs) and their functions. Then, the expression of key DEMs was experimentally validated in exosomes from clinical CHOL patients and CHOL cells. The effects of overexpression of key DEMs on CHOL cell migration and proliferation were investigated. A key exosomal DEM miR-3124-5p was identified. The effects of overexpression or knockdown of exosomal miR-3124-5p on the proliferation, migration, and angiogenesis of human umbilical vein endothelial cells (HUVECs) were investigated. Moreover, the function of exosomal miR-3124-5p on tumor growth in vivo was explored.

Results

A total of 632 exosomal DEMs were identified between CHOL and control samples. Target genes of DEMs were significantly enriched in pathways, such as the p53 signaling pathway. miR-3124-5p was upregulated in serum exosomes from CHOL patients and exosomes from CHOL cells, and overexpression of miR-3124-5p promoted RBE cell migration and viability. Moreover, overexpression of exosomal miR-3124-5p promoted the proliferation, migration, and angiogenesis of HUVECs, while knockdown of miR-3124-5p had the opposite effect. miR-3124-5p could target growth differentiation factor 11 (GDF11) and downregulate GDF11 expression. Furthermore, exosomal miR-3124-5p promoted tumor growth in vivo.

Conclusions

Our findings revealed that exosome-encapsulated miR-3124-5p promoted the malignant progression of CHOL by targeting GDF11. Exosomal miR-3124-5p and GDF11 could be promising biomarkers or therapeutic targets for CHOL.

Exosomal microRNA-23a-3p contributes to the progression of cholangiocarcinoma by interaction with Dynamin3

Cholangiocarcinoma (abbreviated as CCA) accounts for about 3% of digestive tract tumors, which is a rare disease with relatively low incidence. Herein, we firstly discovered overexpression of microRNA-23a-3p (abbreviated as miR-23a-3p) in CCA tissues, as well as cell lines via bioinformatics prediction. Next, by conducting miR-23a-3p knockdown system in HUCCT1 cells and miR-23a-3p overexpression system in RBE cells, we investigated the biological effects of miR-23a-3p. Based on our findings, inhibition of miR-23a-3p was able to prevent cancer cell proliferation via colony formation, CCK-8, as well as EdU assays. Moreover, invasion as well as migration abilities of cells was examined by transwell assay and wound healing test. Animal study further verified that knockdown miR-23a-3p slowed down tumor growth and lung metastasis. In addition, we identified cholangiocarcinoma cells transferred miR-23a-3p through exosomes by a series of assays. Functional experiments have confirmed that exosomal miR-23a-3p could benefit for cancer cell growth and metastasis, serving as a cancer promoting gene. Furthermore, we found Dynamin3 (abbreviated as DNM3) turned out to be a target of miR-23a-3p, while DNM3 was down-regulated in cholangiocarcinoma. Knockdown DNM3 accelerated cancer cell development. Collectively, our findings firstly pointed out that exosomal miR-23a-3p was conducive to the progression of cholangiocarcinoma by interaction with DNM3, which provided potential evidence for cancer treatment.