87 Transcription factor RUNX1 activates OPN to promote tumor progression via MAPK signaling in head and neck cancer

Background Tumor progression and metastasis are still major burdens for head and neck squamous cell carcinoma (HNSCC) and are associated with eventual resistance to prevailing therapies. Complex molecular transcription and downstream signaling pathways have been implicated in the development, progression, invasion, metastasis, and treatment resistance of HNSCC. Runt-related transcription factor 1 (RUNX1) are involved in aggressive phenotypes in several cancers, while the molecular role of RUNX1 underlying cancer progression and metastasis of HNSCC remains largely unknown. Methods RUNX1 expression levels in HNSCC cells and tissues were detected by quantitative real-time PCR (qPCR), Western blotting and immunohistochemistry (IHC). In vitro and in vivo assays were performed to investigate the function of RUNX1 in the metastatic phenotype and the tumorigenic capability of HNSCC cells. Luciferase reporter and chromatin immunoprecipitation (ChIP)-qPCR assays were performed to determine the underlying mechanism of RUNX1-mediated HNSCC aggressiveness. Results In our study, RUNX1 expression was increased with disease progression in patients with HNSCC (figure 1). The silencing of RUNX1 significantly decelerated the malignant progression of HNSCC cells, reduced Osteopontin (OPN) expression in vitro, and weakened the tumorigenicity of HNSCC cells in vivo (figure 2). Moreover, we demonstrated that RUNX1 activated the MAPK signaling by directly binding to the promoter of OPN in tumor progression and metastasis of HNSCC (figure 3). Conclusions Our results may provide new insight into the mechanisms underlying the role of RUNX1 in tumor progression and metastasis and reveal the potential therapeutic target in HNSCC. Ethics Approval The study was approved by the Ethics Board of BenQ Medical Center, the Affiliated BenQ Hospital of Nanjing Medical University. Consent Written informed consent was obtained from the patient for publication of this abstract and any accompanying images. A copy of the written consent is available for review by the Editor of this journal.