Role of dual specificity tyrosine-phosphorylation-regulated kinase 1B (Dyrk1B) in S-phase entry of HPV E7 expressing cells from quiescence

// Na Zhou 1 , Shoudao Yuan 1 , Rongchun Wang 2 , Weifang Zhang 3 and Jason J. Chen 1 1 Cancer Research Center, Shandong University School of Medicine, Jinan, Shandong, China 2 Biology Institute of Shandong Academy of Sciences, Jinan, Shandong, China 3 Institute of Pathogenic Biology, Shandong University School of Medicine, Jinan, Shandong, China Correspondence to: Jason J. Chen, email: // Keywords : HPV, E7, quiescence, S-phase, Dyrk1B, p27 Received : May 25, 2015 Accepted : August 08, 2015 Published : August 19, 2015 Abstract The high-risk human papillomavirus (HPV) is the causative agent for cervical cancer. The HPV E7 oncogene promotes S-phase entry from quiescent state in the presence of elevated cell cycle inhibitor p27Kip1, a function that may contribute to carcinogenesis. However, the mechanism by which HPV E7 induces quiescent cells to entry into S-phase is not fully understood. Interestingly, we found that Dyrk1B, a dual-specificity kinase and negative regulator of cell proliferation in quiescent cells, was upregulated in E7 expressing cells. Surprisingly and in contrast to what was previously reported, Dyrk1B played a positive role in S-phase entry of quiescent HPV E7 expressing cells. Mechanistically, Dyrk1B contributed to p27 phosphorylation (at serine 10 and threonine 198), which was important for the proliferation of HPV E7 expressing cells. Moreover, Dyrk1B up-regulated HPV E7. Taken together, our studies uncovered a novel function of Dyrk1B in high-risk HPV E7-mediated cell proliferation. Dyrk1B may serve as a target for therapy in HPV-associated cancers.