Deng P, et al. - Researchers sought to determine the role of super elongation complex (SEC) in head and neck squamous cell carcinoma (HNSCC) development. Findings revealed dramatic upregulation of expression of AF4/FMR2 family member 4 (AFF4), the core component of SEC, in HNSCC cell lines and tumor tissues. In this work, AFF4 was demonstrated to promote proliferation, migration and invasion of HNSCC cells. In the regulation of HNSCC cell behaviors, a role of AFF4 was mainly mediated by sex-determining region Y box2 (SOX2), a critical regulator involved in development of several human cancers. SOX2 expression changed in parallel with AFF4 expression in response to depletion and overexpression of AFF4, respectively. In conclusion, AFF4 seems to have a potential for serving as a biomarker and a potential target of therapies for patients with HNSCC.