Novel hypoxia features with appealing implications in discriminating the prognosis, immune escape and drug responses of 947 hepatocellular carcinoma patients

Transl Cancer Res. 2022 Jul;11(7):2097-2121. doi: 10.21037/tcr-22-253.

Abstract

Background: Hypoxia has a profound impact on the development and progression of hepatocellular carcinoma (HCC). This study aimed to explore and elucidate how hypoxia affect prognosis, immune escape and drug responses in HCC.

Methods: HCC-specific hypoxia signatures were identified based on the intersect of differentially expressed genes (DEGs) of GSE41666 and GSE15366. The hypoxia score was calculated using the gene set variation analysis (GSVA) function and validated on GSE18494. We collected five cohorts [The Cancer Genome Atlas (TCGA), GSE14520, GSE39791, GSE36376, GSE57957] for further analysis. First, we analyzed the effect of the hypoxia score on prognosis. Next, we systematically analyzed the potential hypoxia-related immune escape mechanisms and the effect of hypoxia upon immunotherapy. Then, we predicted and screened potential sensitive drugs for HCC patients with high hypoxia levels using machine learning and docking.

Results: We constructed a novel HCC-specific hypoxia score and undertook further analysis in five cohorts (TCGA, GSE14520, GSE39791, GSE36376, GSE57957). We observed that patients with high hypoxia scores exhibited worse overall survival (OS) in TCGA and GSE14520. We also constructed a hypoxia-related nomogram that had good performance in predicting HCC patients' prognosis. Furthermore, patients with lower hypoxia scores had a lower risk of immune escape and thus may benefit from immunotherapy. Finally, we predicted and screened VLX600 as the candidate drug for HCC patients with high hypoxia scores. We further explored and elucidated why VLX600 was more sensitive in HCC patients with high hypoxia than with low hypoxia HCC patients using weighted gene co-expression network analysis (WGCNA).

Conclusions: This study provides further evidence of the link between hypoxia and prognosis and immune escape in HCC patients. Moreover, our research screened VLX600 as a potential drug for HCC patients with high hypoxia levels and elucidated the potential mechanism.

Keywords: Hypoxia; biomarker; hepatocellular carcinoma (HCC); immune escape; immunotherapy.