JCT  Vol.4 No.5 , July 2013
REGγ Mediated Regulation of p21Waf/Cip1, p16INK4a and p14ARF/p19ARF in Vivo

p21Waf/Cip1, p16INK4a and p14ARF (p19ARF in mice) have been demonstrated to be degraded by REGγ-proteasome pathway in an ATP- and ubiquitin-independent manner in vitro. However, the in vivo roles of REGγ mediated-degradation of p21Waf/Cip1, p16INK4a and p14ARF remain unclear. In this study, we showed enhanced expression of p21Waf/Cip1, p16INK4a and p19ARF in multiple tissues from REGg–/– mice compared to REGg+/+ mice. Furthermore, we examined the expression of p21Waf/Cip1, p16INK4a and p14ARF in different cancer tissues and observed that the REGγ protein levels were highly expressed in different human cancers while the level of p21Waf/Cip1, p16INK4a and p14ARF appears to be inversely correlated. These results demonstrate that REGγ may exert its function in physiological and pathological conditions through degradation of p21Waf/Cip1, p16INK4a and p14ARF in vivo.

Cite this paper
L. Li, P. Zhang, H. Wei, W. Wang, L. Yao, Y. Li, L. Zhou, Z. Wang, J. Liu, L. Zhou, A. Amjad, B. Zhang, T. Jing, J. Xiao, Y. Dang and X. Li, "REGγ Mediated Regulation of p21Waf/Cip1, p16INK4a and p14ARF/p19ARF in Vivo," Journal of Cancer Therapy, Vol. 4 No. 5, 2013, pp. 933-938. doi: 10.4236/jct.2013.45104.
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