Sheng Wang,1– 3,* Wufei Ye,1,3,* Kui Yang,1,3 Xiongwen Lv,2 Jiajie Luan1,3 

1Department of Pharmacy, The First Affiliated Hospital of Wannan Medical College (Yijishan Hospital of Wannan Medical College), Wuhu, Anhui, 241001, People’s Republic of China; 2The Key Laboratory of Anti-Inflammatory and Immune Medicines, Ministry of Education, Anhui Province Key Laboratory of Major Autoimmune Diseases, School of Pharmacy, Institute for Liver Disease of Anhui Medical University, Hefei, Anhui, 230032, People’s Republic of China; 3School of Pharmacy, Wannan Medical College, Wuhu, Anhui, 241002, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Xiongwen Lv, The Key Laboratory of Anti-inflammatory and Immune medicines, Ministry of Education, Anhui Province Key Laboratory of Major Autoimmune Diseases, School of Pharmacy, Institute for Liver Disease of Anhui Medical University, Hefei, Anhui, 230032, People’s Republic of China, Email xiongwen_lv2019@163.com Jiajie Luan, Department of Pharmacy, The First Affiliated Hospital of Wannan Medical College (Yijishan Hospital of Wannan Medical College), Wuhu, Anhui, 241001, People’s Republic of China, Email luanjiajie775@163.com

Objective: Hepatocellular carcinoma (HCC) is the predominant form of liver cancer. Hypoxia can be involved in HCC tumor growth, invasion and metastasis through inducing angiogenesis. Nevertheless, the assessment of the impact of hypoxia and angiogenesis on the prognosis of HCC remains inadequate.
Methods: According to hypoxia-angiogenesis-related genes (HARGs) expression information and clinical data from patients within the Cancer Genome Atlas-Liver Hepatocellular Carcinoma (TCGA-LIHC) cohort, we constructed a prognostic model (HARG-score) using bioinformatic tools. In addition to assessing the predictive ability of this prognostic model in both Liver Cancer-Riken-Japan (LIRI-JP) and GSE14520 cohorts, we analyzed the correlation between HARG-score and clinical characteristics, immune infiltration and immunotherapy efficacy. Moreover, we investigated the exact role and underlying mechanism of key HARGs through molecular experiments.
Results: We constructed a 5-gene prognostic model HARG-score consisting of hypoxia-inducible lipid droplet-associated (HILPDA), erythropoietin (EPO), solute carrier family 2 member 1 (SLC2A1), proteasome subunit alpha type 7 (PSMA7) and cAMP responsive element-binding protein 1 (CREB1) through differentially expressed HARGs. The findings demonstrated that HARG-score was a good predictor of the prognosis of HCC patients from distinct cohorts and was correlated with clinical characteristics and immune infiltration. Furthermore, the HARG-score was identified as an independent prognostic factor. Lower HARG-score implied greater immunotherapy efficacy and better response. The expression and prognostic significance of these 5 genes were additionally validated in clinical data. In addition, experimental data revealed that the key gene HILPDA contributes to the progression of HCC through facilitating angiogenesis and affecting the expression of cytotoxic T-lymphocyte-associated protein 4 (CTLA4).
Conclusion: HARG-score has promising applications in prognosis prediction of HCC patients, in which HILPDA may be a latent prognostic biomarker and therapeutic target, providing a foundation for further research and treatment of HCC.

Keywords: hepatocellular carcinoma, hypoxia-angiogenesis, HILPDA, prognosis, immunotherapy efficacy