The Overactivation of NADPH Oxidase during Clonorchis sinensis Infection and the Exposure to N-Nitroso Compounds Promote Periductal Fibrosis

Clonorchis sinensis-infected hepatocellular carcinoma exhibits distinct tumor microenvironment and molecular features

Objectives

Clonorchis sinensis (Cs)-infected hepatocellular carcinoma (HCC) patients have a poorer prognosis than non-Cs-infected HCCs. However, the molecular mechanisms of Cs-infected HCC remain unclear. To address this, this study aims to uncover the tumor microenvironment and molecular features that may contribute to these poor outcomes.

Methods

The research involved bulk RNA sequencing of paired tumor and adjacent tissue samples from 10 Cs + HCC and 10 Cs - HCC patients. Differentially expressed genes were identified, followed by enrichment analyses to reveal functional changes. Survival analysis of the top 10 up- and down-regulated genes in Cs + HCC tumors was performed using TCGA database. Additionally, clinical data from 1,461 HCC patients were retrospectively analyzed to assess the impact of Cs infection on microvascular invasion and metastasis rates. In vitro assays were also conducted using Cs excretory/secretory products (CsESPs) to examine their effect on HCC cells and HUVECs.

Results

We identified 785 up-regulated and 675 down-regulated genes in Cs + HCC tumors compared to Cs - HCC tumors, enriched in pathways related to extracellular matrix remodeling and immunosuppression. Survival analysis revealed that the top 10 up-regulated genes are associated with HCC poor prognosis. Clinical data from 1,461 HCC patients showed Cs infection increased microvascular invasion and metastasis rates. In vitro, CsESPs products enhanced migration and invasion in HCC cells and promoted tube formation in human umbilical vein endothelial cells.

Conclusions

This study provides novel insights into the molecular landscape of Cs-infected HCC and underscores the Cs infection's role in enhancing tumor migration, invasion and angiogenesis. The findings contribute to the understanding of parasitic infections in cancer progression and suggest potential prognostic markers for Cs + HCC.

The crosstalk between cholangiocytes and hepatic stellate cells promotes the progression of epithelial-mesenchymal transition and periductal fibrosis during Clonorchis sinensis infection

ABSTRACT: BACKGROUND: Clonorchis sinensis infection is one of the risk factors that provokes chronic inflammation, epithelial hyperplasia, periductal fibrosis and even cholangiocarcinoma (CCA). Disrupted or aberrant intercellular communication among liver-constituting cells leads to pathological states that cause various hepatic diseases. This study was designed to investigate the pathological changes caused by C. sinensis excretory-secretory products (ESPs) in non-cancerous human cell lines (cholangiocytes [H69 cell line] and human hepatic stellate cells [LX2 cell line]) and their intercellular crosstalk, as well the pathological changes in infected mouse liver tissues.

METHODS

The cells were treated with ESPs, following which transforming growth factor beta 1 (TGF-β1) and interleukin-6 (IL-6) secretion levels and epithelial-mesenchymal transition (EMT)- and fibrosis-related protein expression were measured. The ESP-mediated cellular motility (migration/invasion) between two cells was assessed using the Transwell and three-dimensional microfluidic assay models. The livers of C. sinensis-infected mice were stained using EMT and fibrotic marker proteins.

RESULTS

Treatment of cells with ESPs increased TGF-β1 and IL-6 secretion and the expression of EMT- and fibrosis-related proteins. The ESP-mediated mutual cell interaction further affected the cytokine secretion and protein expression levels and promoted cellular motility. N-cadherin overexpression and collagen fiber deposition were observed in the livers of C. sinensis-infected mice.

CONCLUSIONS

These findings suggest that EMT and biliary fibrosis occur through intercellular communication between cholangiocytes and hepatic stellate cells during C. sinensis infection, promoting malignant transformation and advanced hepatobiliary abnormalities.