# Venous endothelial remodeling mediated by MARCKS promotes angiogenesis and tumor progression in hepatocellular carcinoma: insights from single-cell RNA sequencing

## TL;DR

This study shows that venous endothelial cells and the MARCKS gene play a key role in liver cancer growth and blood vessel formation, offering new targets for treatment.

## Contribution

The study identifies venous endothelial cell heterogeneity and MARCKS as a novel driver of tumor angiogenesis in hepatocellular carcinoma.

## Key findings

- Venous endothelial cells are key initiators of tumor angiogenesis in HCC.
- MARCKS knockdown reduces endothelial cell proliferation, migration, and tumor growth in vivo.
- MARCKS is a robust predictor of poor clinical outcomes in HCC patients.

## Abstract

Hepatocellular carcinoma (HCC) is characterized by pronounced heterogeneity and extensive angiogenesis. However, anti-angiogenic therapies often show limited clinical benefit due to therapeutic resistance. Understanding endothelial cell heterogeneity and identifying key regulators of tumor angiogenesis are therefore essential for improving treatment strategies.

We integrated multiple single-cell RNA sequencing (scRNA-seq) datasets to systematically characterize endothelial cell heterogeneity in the HCC microenvironment. Based on genes enriched in venous endothelial cells, we developed a prognostic risk model termed the Vein Endothelial-related Risk Scores (VERS). The functional role of the key gene MARCKS was further evaluated using in vitro assays and in vivo xenograft models.

Venous endothelial cells (VenECs) were identified as key initiators of tumor angiogenesis in HCC. Among the VERS genes, MARCKS emerges as a robust predictor of poor clinical outcome. Functional assays reveal that MARCKS knockdown impairs endothelial cell proliferation, migration and invasion, and attenuates the pro-tumorigenic effects of endothelial-conditioned media. In vivo, MARCKS silencing significantly suppresses tumor growth and vascularization.

Our findings reveal a critical role for venous endothelial cells in HCC angiogenesis and identify MARCKS as a potential therapeutic target, providing molecular insights for precision oncology in HCC.