Abstract
Hepatocellular carcinoma (HCC) is one of the major causes of cancer-associated morbidity and mortality worldwide. Sphingosine-1-phosphate (S1P) and S1P receptor 1 (S1PR1) have been associated with the development and progression of HCC. Angiotensin II (Ang II) and Ang II receptor type 1 (AT1R) serve key roles in the progression and metastasis of HCC. However, the association and roles of Ang II/AT1R and S1P/S1PR1 in HCC have remained elusive. Therefore, the aim of the present study was to investigate the potential association between Ang II/AT1R and S1P/S1PR1 in HCC, as well as the association of AT1R and S1PR1 protein expression levels with the progression and prognosis of HCC. The results found that the serum levels of Ang II and S1P were significantly higher in patients with HCC compared with those in healthy donors. Furthermore, mRNA and protein levels of AT1R and S1PR1 were highly expressed in human HCC tissues. In addition, a positive correlation between Ang II/S1P and AT1R/S1PR1 in HCC was noted. Upregulation of AT1R and S1PR1 was associated with the progression of HCC. Patients with high AT1R and S1PR1 protein expression levels had unfavorable outcomes with respect to overall survival and recurrence-free survival compared with patients with low AT1R and S1PR1 expression levels. The present results demonstrated an association between AT1R and S1PR1 overexpression and the progression of HCC, indicating that Ang II/AT1R and S1P/S1PR may serve as valuable prognostic biomarkers for HCC.