Study On The CDKN3 Role In Tumorigenesis Mediated By BCR-ABL

This study explored the critical role of CDKN3 in Bcr-Abl-mediated tumorigenesis by in vitro and in vivo experiments.Human K562 cell line,K562 cells silencing or overexpressing CDKN3,and nude mices were used in this project.The experiment of my master's thesis is based in K562 cells.Respectively,through the construction of stable expression of CDKN3 and interference CDKN3 stable cell lines.Under the specific induction of apoptosis,inhibitor of ABL,imatinib,we observed difference of viability between experimental and control groups.Besides,the protein level of anti-apoptotic proteins and genes were analyzed by western blot and RT-PCR.At the same time,we also conducted experiments tumorigenicity in nude mice.The 419 base site of CDKN3 was reported to be crucial for the interaction with the downstream protein.Similarly,a mutant form of stable high expression cell line was constructed to observe the effect on apoptosis.We are also wondering whether CDKN3 affect the apoptosis through CDK2.Finally,CDKN3 as the impact of the activity of cyclin-CDK2 protein,we observe and analyze the impact of CDKN3 on the cell cycle.The results are shown as follow.a.Overexpression of CDKN3 increases apoptosis induced by imatinib,while knockdown of CDKN3 has the opposite result.b.Increasing expression level of CDKN3 efficaciously inhibits tumor formation in nude mouse model.While knockdown of CDKN3 promote tumor formation in nude mouse model.c.The phosphatase activity of CDKN3 is required for regulation of apoptosis and carcinogenesis in K562 cells.d.CDKN3 can affect the level of anti-apoptotic protein level,such as XIAP through CDK2,thus affect the survival of cells.e.CDKN3 has an essential role in regulating S phase entry.