MDM2 and cervical carcinoma: In normalcells, p53 levels are under negative regulation of Mdm2 ubiquitin ligase andp53 pathway activation primarily involves signal-dependent escape fromdegradation [54,55].Whereas in high-risk HPV-transformed cervical cancer cells, the viraloncoprotein E6 binds to p53 and with the help of the cellular ubiquitin ligaseE6-AP, p53 is targeted for constitutive degradation through the ubiquitinproteasomal pathway [6,32,56].