Rui Chen,1 Xi Wang,2,3 Shixian Zhou,2,4 Zongyue Zeng2 1Department of Oral and Maxillofacial Surgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, Peopleâs Republic of China; 2Department of Laboratory Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, Peopleâs Republic of China; 3Key Laboratory of Diagnostic Medicine Designated by the Ministry of Education, Department of Laboratory Medicine, Chongqing Medical University, Chongqing, 400016, Peopleâs Republic of China; 4Department of Pathology, Central Hospital of Jiangjin District, Chongqing, 402260, Peopleâs Republic of ChinaCorrespondence: Zongyue ZengDepartment of Laboratory Medicine, The First Affiliated Hospital of Chongqing Medical University, No.1 Youyi Road, Yuzhong District, Chongqing, 400016, Peopleâs Republic of ChinaTel +86 23-8895-5532Email zengzongyue@126.comIntroduction: Growing evidence suggests that long non-coding RNAs (lncRNAs), such as lncRNA HOXA-AS2, are critical regulators involved in human cancer. However, the biological functions and detailed mechanisms underlying how lncRNA HOXA-AS2 affects oral squamous cell carcinoma (OSCC) remain unexplored.Methods: The expression of lncRNA HOXA-AS2 and miR-567 was determined in OSCC cell lines and clinical tissues by quantitative real-time PCR (qRT-PCR). Target site prediction and luciferase report assays were used to explore their potential interaction and binding sites between lncRNA HOXA-AS2 and miR-567. Overexpression or silencing expression of lncRNA HOXA-AS2 was performed to confirm that miR-567 was suppressed by lncRNA HOXA-AS2. WST-1 assay, crystal staining assay, and cell cycle analysis were used to assess the cell viability and proliferation ability. The target gene of miR-567 was predicted by Targetscan and validated by luciferase report assay as well as qRT-PCR and Western Blot. Xenograft nude mice model was done to demonstrate that lncRNA HOXA-AS2 promoted cell proliferation via targeting miR-567/CDK8 in vivo.Results: LncRNA HOXA-AS2 was up-regulated in OSCC cells and tissues with the expression of miR-567 decreased. The tissue lncRNA HOXA-AS2 expression was found to positively correlate with the TNM stage and lymph node metastasis of OSCC patients. In terms of the mechanism, we found that lncRNA HOXA-AS2 negatively regulates miR-567 expression via a direct interaction. Functionally, overexpression of lncRNA HOXA-AS2 significantly promoted OSCC cell proliferation, while knockdown of lncRNA HOXA-AS2 significantly inhibited it. We also observed that miR-567 directly targets the 3ʹ UTR of CDK8. Moreover, silencing lncRNA HOXA-AS2 inhibited tumor growth with the expression of miR-567 increased and CDK8 decreased in vivo.Conclusion: LncRNA HOXA-AS2 was up-regulated in OSCC, and its up-regulation correlated with poor clinical outcomes. The lncRNA also promoted OSCC cell proliferation by directly binding to miR-567, leading to an increase in CDK8 expression. The potential prognostic value of lncRNA HOXA-AS2 should be explored in future studies.Keywords: LncRNA HOXA-AS2, MiR-567, CDK8, Oral squamous cell carcinoma, Tumor progression