A dual role for interferon γ signalling in hepatocellular carcinoma

Polyribonucleotide phosphorylase is overexpressed in hepatocellular cancer, promoting epithelial phenotype maintenance and tumor progression

Liver cancer, particularly hepatocellular carcinoma (HCC), is a major global health challenge, largely associated with cirrhosis caused by various factors. Prognosis is often guided by molecular and histological classifications. In this study, expression of Polyribonucleotide Phosphorylase (PNPT1) in HCC was investigated to better understand its role in tumor behavior and patient outcomes. The expression of the corresponding protein PNPase was assessed in HCC tissue samples using immunohistochemistry, while RNA-seq data from The Cancer Genome Atlas (TCGA) were analyzed via OncoDB. Additionally, PNPT1 silencing in HepG2 cells was followed by gene and protein expression analysis. The results revealed that PNPT1 is overexpressed in HCC tumors, particularly in those expressing E-cadherin. Notably, silencing PNPT1 in HepG2 cells triggered a shift towards a mesenchymal phenotype. In HCC tissues, PNPT1 expression was linked to markers of epithelial phenotype, oxidative stress, and poor prognosis, especially in non-viral HCC cases. These findings suggest that PNPase may play a crucial role in the progression of well-differentiated HCC tumors, serving as a poor prognostic biomarker.

The Therapeutic Potential of Adipose Tissue-Derived Mesenchymal Stem Cells to Enhance Radiotherapy Effects on Hepatocellular Carcinoma

Several studies have investigated strategies to improve the clinical efficacy of radiotherapy (RT) against hepatocellular carcinoma (HCC), yet the prognosis remains poor. Human adipose tissue-derived mesenchymal stem cells (AT-MSCs), easily accessible and abundant in quantity, have represented as an attractive therapeutic tool for the stem cell-based treatment for cancer diseases. Through direct co-culture and indirect separate culture experiments, we showed that AT-MSCs could enhance inhibitory effect of RT on reducing HCC cell growth, migration and invasion in both in vitro and in vivo experiments. RNA-sequencing analysis revealed a noticeable interferon-induced transmembrane 1 (IFITM1)-induced tumor gene signature. Gain and loss of mechanistic studies indicated that mechanism was attributed to downregulated expression of signal transducer and activator of transcription 3 (STAT3) and matrix metallopeptidases (MMPs) and upregulated expression of P53 and caspases. Collectively, our findings suggest that AT-MSCs might enhance the therapeutic effects of RT on HCC, providing a rationale for AT-MSCs and RT combination therapy as a new remedy for HCC.

A meta-analysis for C-X-C chemokine receptor type 4 as a prognostic marker and potential drug target in hepatocellular carcinoma

Chemokines (CKs), small proinflammatory chemoattractant cytokines that bind to specific G-protein coupled seven-span transmembrane receptors, are major regulators of cell trafficking and adhesion. C-X-C chemokine receptor type 4 (CXCR4) has gained tremendous attention over the last decade, since it was found to be upregulated in a wide variety of cancer types, including hepatocellular carcinoma (HCC). The clinical relevance of expression of CXCR4 in HCC remains controversial; our aim was to identify the precise relationship of CXCR4 to prognosis and clinicopathological features. We searched the database from MEDLINE, PubMed, Web of Science, Scopus and Embase and then conducted a meta-analysis from publications met the inclusion criteria for the qualitative study. Our data showed that 1) CXCR4 is overexpressed in HCC tissues but not in normal hepatic tissue, OR =84.26, 95% confidence interval (CI) =11.86–598.98, P<0.0001. CXCR4 expression is higher in HCC than those in cirrhosis as well, OR =20.71, 95% CI =7.61–56.34, P<0.00001. 2) The expression levels of CXCR4 does not increase during local progression, however, CXCR4 expression increases the risk of distant metastases in HCC, OR =5.84, 95% CI =2.84–12.00, P<0.00001. 3) High levels of CXCR4 gene expression are associated with worse survival in HCC, HR =0.18, 95% CI =0.10–0.32, Z=5.77, P<0.00001. These data indicate that CXCR4 expression correlates with an increased risk and worse survival in HCC patients. The aberrant CXCR4 expression plays an important role in the carcinogenesis and metastasis of HCC. Our conclusion also supports that the promise of CXCR4 signaling pathway blockade as a potential strategy for HCC patients.

STAT3 in hepatocellular carcinoma: new perspectives

Chronic liver damage and inflammation are strong promoters of hepatocellular carcinoma (HCC) formation. HCC cells communicate with inflammatory and stromal cells via cytokine/chemokine signals. These heterotypic interactions inhibit immunologic anticancer activities and promote protumorigenic activities, such as angiogenesis or invasiveness. STAT3 mediates several reciprocal interactions between liver cancer cells and stromal cells and modulates preconditions of tumor formation such as chronic inflammation. Therefore, activation of STAT3 is considered as a tumor-promoting event in HCC formation. However, the oncogenic role of STAT3 in cancers has been challenged by several reports that suggest a tumor-suppressive activity. Here we discuss tumor-promoting and tumor-suppressive effects of cytokine-activated STAT3 in HCC.