Hyaluronan Elevates Cell Cycle Regulators P130, E2F4, and P27kip1 in Dormant Human Mesenchymal Stem Cells to Regulate Cell Quiescence

Quiescence conserves the properties of stem cells whilst they are dormant. The mechanisms associated with dormancy involve various cell regulators. Here, the effects of hyaluronan (HA; a polysaccharide associated with the extracellular matrix), on the mesenchymal stem cell cycle and the involvement of p130 and E2F family proteins in mesenchymal stem cell cycle regulation, were evaluated. Placenta-derived mesenchymal stem cells (PDMSCs) were cultured on either a normal tissue culture surface (TCS) or a surface coated with HA. Cell population percentages at the G0/G1, S, and G2/M phases were analyzed 36, 40, 44, 48, and 50 h post-seeding using flow cytometry. At 36 h, HA-treated cells had more PDMSCs in the G0/G1 phase (61.59% versus 43.61% in the TCS group). At and 48 and 50 h for the HA and TCS groups, respectively, PDMSCs had highly similar population distributions in cell cycle phases; thus, these cells were used to study cell cycle regulators. Pocket proteins (p130, p107, and pRb), E2F family proteins (E2F3, E2F4, and E2F5), using sand the binding of p130 to E2F4 and DP1 were analyzed with western blots and coimmunoprecipitation. The HA group at 48 h exhibited increased p130 and E2F4 protein expression compared with the TCS group at 50 h (4.3-fold and 1.5-fold, respectively), and the binding of p130 to E2F4 and DP1 was detected 36, 48, and 50 h post-seeding. In this studyHence, a the HA-regulated formation of a p130/E2F4 complex was observed in PDMSCs, which provides to suggests that the mesenchymal stem cell cycle is regulated by HA as an extracellular matrix. Hyaluronan Elevates Cell Cycle Regulators P130, E2F4, and P27kip1 in Dormant Human Mesenchymal Stem Cells to Regulate Cell Quiescence Meei-Ru Lin1*, Tzyy Yue Wong1, Chun-Hsien Wu1 and Lynn LH Huang1-4 1Institute of Biotechnology, College of Bioscience and Biotechnology, National Cheng Kung University, Taiwan 2Research Center of Excellence in Regenerative Medicine, National Cheng Kung University, Tainan, Taiwan 3Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan 4Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan, Taiwan *Corresponding author: Meei-Ru Lin, Institute of Biotechnology, College of Bioscience and Biotechnology, National Cheng Kung University, Taiwan, Tel: +8867-3450359; Fax: +886-06-2080165; E-mail: [email protected] Received June 06, 2016; Accepted June 23, 2016; Published June 27, 2016 Citation: Lin MR, Wong TY, Wu CH, Huang LLH (2016) Hyaluronan Elevates Cell Cycle Regulators P130, E2F4, and P27kip1 in Dormant Human Mesenchymal Stem Cells to Regulate Cell Quiescence. J Stem Cell Res Ther 6: 345. doi:10.4172/21577633.1000345 Copyright: © 2016 Lin MR, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.