Open AccessSkp2‐mediated degradation of p27 regulates cell cycle progression in compressed human bladder smooth muscle cells
Author(s) -
Chen Lin,
Wu Tao,
Wei TangQiang,
Wei Xin,
Li ShengFu,
Wang KunJie,
Li Hong
Publication year - 2014
Publication title -
the kaohsiung journal of medical sciences
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.439
H-Index - 36
eISSN - 2410-8650
pISSN - 1607-551X
DOI - 10.1016/j.kjms.2013.07.002
Subject(s) - medicine , cell cycle , gene silencing , cell growth , flow cytometry , hyperplasia , signal transduction , cell , microbiology and biotechnology , cancer research , pathology , biology , immunology , gene , biochemistry , cancer
Bladder outlet obstruction (BOO) results in smooth muscle cell hyperplasia, decreased bladder wall compliance, and lower and upper urinary tract pathology. Mechanical stimulus on detrusor tissue is critical to BOO disease progression. Our previous studies confirm that mechanical stimulus triggers human bladder smooth muscle cell (HBSMC) proliferation. To better understand the signal transduction mechanisms for this process we detected cell cycle machinery of HBSMC (Bose ® Biodynamic, Minnetonka, MN, USA). HBSMCs cultured in scaffolds were subjected to four different pressures (0 cmH 2 O, 100 cmH 2 O, 200 cmH 2 O, and 300 cmH 2 O) for 24 hours, which were controlled by a BOSE BioDynamic bioreactor. Then we used flow cytometry to examine cell cycle distribution, polymerase chain reaction, and immunoblotting to quantify Skp2, p27, and p21 expression in each group. Additionally, Skp2 was silenced in HBSMCs using small interfering RNA to validate the role of Skp2 in mediating pressure‐induced cell cycle progression. Compared with the 0 cmH 2 O control, HBSMCs in the 200 cmH 2 O and 300 cmH 2 O groups exhibited high‐level expression of Skp2 gene and low‐level expression of p27 protein. However, p21, another downstream signal of Skp2, showed no significant change between groups. In addition, Skp2 silencing abolished increases in cell proliferation induced by pressure. To the best of our knowledge, this is the first report on the functional importance of Skp2 in cyclic hydrodynamic pressure stimulated HBSMC proliferation. The signal transduction mechanism for this process involves p27 as well as p21 signaling pathway.