ObjectiveRecent studies were widely concerned about the role of lncRNAs in hypoxic pulmonary hypertension (HPH). HAS2 was found significantly highly expressed in HPH, but the antisense of HAS2 (HAS2-AS1) has not been explored in HPH, providing a new potential therapeutic target of HPH.MethodsIn this study, human fetal lung fibroblast-1 (HFL-1) cells were cultured under hypoxia conditions to stimulate the pathological process of HPH. Transwell and wound-healing assays were used to detect HFL-1 cell migration, and CCK 8 assay was used to detect cell proliferation. The upstream transcription factor of HAS2-AS1 was predicted by JASPAR website, and the binding site between C/EBPβ and HAS2-AS1 was predicted by JASPAR, too. In order to verify the association between C/EBPβ and the HAS2 promoter region, we used chromatin immunoprecipitation (ChIP) and dual luciferase reporter gene detection, western blot to detect the expression of inflammation-related proteins, and qRT-PCR to detect the expression of HAS2-AS1 and HAS2. Idiopathic pulmonary fibrosis (IPF) with HPH patient microarray data was downloaded from the GEO database and analyzed by R software.ResultsOur study showed that HAS2-AS1 and C/EBPβ were highly expressed in hypoxic HFL-1 cells, and the knockdown of HAS2-AS1 expression could inhibit the proliferation, migration, and inflammatory response of HFL-1 cells. C/EBPβ binds to the promoter region of HAS2-AS1 and has a positive regulation effect on the transcription of HAS2-AS1. Furthermore, C/EBPβ can regulate the proliferation, migration, and inflammatory response of HFL-1 cells through HAS2-AS1.ConclusionThis study suggested that C/EBPβ could upregulate HAS2-AS1 expression and induce HFL-1 cell proliferation, migration, and inflammation response.