AUTHOR=Yao Fuwen , Zhan Yongqiang , Li Changzheng , Lu Ying , Chen Jiao , Deng Jing , Wu Zijing , Li Qi , Song Yi’an , Chen Binhua , Chen Jinjun , Tian Kuifeng , Pu Zuhui , Ni Yong , Mou Lisha 

TITLE=Single-Cell RNA Sequencing Reveals the Role of Phosphorylation-Related Genes in Hepatocellular Carcinoma Stem Cells

JOURNAL=Frontiers in Cell and Developmental Biology

VOLUME=9

YEAR=2022

URL=https://www.frontiersin.org/journals/cell-and-developmental-biology/articles/10.3389/fcell.2021.734287

DOI=10.3389/fcell.2021.734287

ISSN=2296-634X

ABSTRACT=<p>Abnormal activation of protein kinases and phosphatases is implicated in various tumorigenesis, including hepatocellular carcinoma (HCC). Advanced HCC patients are treated with systemic therapy, including tyrosine kinase inhibitors, which extend overall survival. Investigation of the underlying mechanism of protein kinase signaling will help to improve the efficacy of HCC therapy. Combining single-cell RNA sequencing data and TCGA RNA-seq data, we profiled the protein kinases, phosphatases, and other phosphorylation-related genes (PRGs) of HCC patients in this study. We found nine protein kinases and PRGs with high expression levels that were mainly detected in HCC cancer stem cells, including <italic>POLR2G</italic>, <italic>PPP2R1A</italic>, <italic>POLR2L</italic>, <italic>PRC1</italic>, <italic>ITBG1BP1</italic>, <italic>MARCKSL1</italic>, <italic>EZH2</italic>, <italic>DTYMK,</italic> and <italic>AURKA.</italic> Survival analysis with the TCGA dataset showed that these genes were associated with poor prognosis of HCC patients. Further correlation analysis showed that these genes were involved in cell cycle-related pathways that may contribute to the development of HCC. Among them, <italic>AURKA</italic> and <italic>EZH2</italic> were identified as two hub genes by Ingenuity Pathway Analysis. Treatment with an AURKA inhibitor (alisertib) and an EZH2 inhibitor (gambogenic) inhibited HCC cell proliferation, migration, and invasion. We also found that both <italic>AURKA</italic> and <italic>EZH2</italic> were highly expressed in <italic>TP53</italic>-mutant HCC samples. Our comprehensive analysis of PRGs contributes to illustrating the mechanisms underlying HCC progression and identifying potential therapeutic targets for future clinical trials.</p>