Exosomal microRNAs in the DLK1-DIO3 imprinted region derived from cancer-associated fibroblasts promote progression of hepatocellular carcinoma by targeting hedgehog interacting protein

Abstract

Background Hepatocellular carcinoma (HCC) is the sixth most commonly diagnosed cancer and third leading cause of cancer-related death worldwide in 2020. Exosomes derived from cancer-associated fibroblasts (CAFs-exo) can promote tumor progression in various human cancers. However, the underlying regulatory mechanism controlling how CAFs-exo can promote HCC progression remains poorly understood. Methods CAFs and para-cancer fibroblasts (PAFs) were isolated from HCC tissues and corresponding para-cancer tissues, then were cultured in vitro. CAFs and PAFs were characterized by immunofluorescence and western blot (WB) assays. Exosomes were isolated by ultracentrifugation, and characterized by transmission electron microscopy, nanoflow cytometry, and WB assay. The internalization of exosomes by HCC cells was observed under a fluorescence microscope. Cell Counting Kit-8 (CCK-8) assay was used to evaluate cell proliferation. Wound healing and transwell assays were used for migration and invasion experiments. RT-PCR assay was used to examine differentially expressed microRNAs (miRNAs) in exosomes and HCC cells. The TargetScan database was used to predict miRNA target genes. Hedgehog interacting protein (HHIP) expression analysis, prognostic analysis, and enrichment analysis of HHIP-related co-expressed genes were performed using the TIMER, UALCAN, Kaplan–Meier plotter, and LinkedOmics databases. Results CAFs-exo were internalized by HCC cells. CAFs-exo contributed to the aggressive phenotype of HCC cells, while inhibiting exosome secretion reversed these effects. Mechanistically, miRNAs in the DLK1-DIO3 imprinted region (miR-329-3p, miR-380-3p, miR-410-5p, miR-431-5p) were increased in HCC cells co-cultured with CAFs-exo compared with PAFs-exo. Expression of HHIP, a possible miR-431-5p target gene, was significantly downregulated in HCC cells. Low HHIP expression level in tumor tissues could predict poor prognosis in HCC patients. HHIP-related co-expressed genes were mainly associated with cell adhesion molecules. Conclusions CAFs-exo can promote HCC progression by delivering miRNAs in the DLK1-DIO3 imprinted region to HCC cells, subsequently inhibiting HHIP expression. HHIP is a potential prognostic biomarker in HCC.

The hidden messengers: cancer associated fibroblasts—derived exosomal miRNAs as key regulators of cancer malignancy

“…miRNAs in the DLK1-DIO3 imprinting area, including miR-329-3p, miR-380-3p, miR-410-5p, and miR-431-5p, were found to be upregulated in hepatocellular carcinoma (HCC) cells co-cultured with exosomes produced from CAFs. These miRNAs inhibited HHIP expression, weakened cell adhesion, and enabled cell migration and invasion ( Jin et al, 2022 ). In HCC, miR-20a-5p has been demonstrated to have a comparable impact ( Qi et al, 2022 ).…”

Intercellular crosstalk between cancer cells and cancer-associated fibroblasts via exosomes in gastrointestinal tumors

“…CAFs derived exosomes could also dramatically elevate the rates of intrahepatic and pulmonary metastasis of HCC. Jin et al (138), demonstrated that exosomes separated from CAFs could be absorbed by HCC cells and accelerated their invasive phenotype compared with para-cancerous fibroblasts (PAFs), and mechanistic experiments revealed that CAFs could offer multiple miRNAs (miR-329-3p, miR-380-3p, miR-410-5p, miR-431-5p) were delivered to HCC cells and increased their expression levels. Additionally, downregulation of LIMA1 expression was associated with poor OS and recurrence-free survival (RFS) in HCC patients.…”