Induction of apoptosis in p16INK4A mutant cell lines by adenovirus-mediated overexpression of p16INK4A protein.
The tumor suppressor gene p16INK4A is a cyclin-dependent kinase inhibitor (CDKI) and an important cell cycle regulator. We have previously constructed a recombinant adenovirus which expresses p16 (Adp16) and shown that infection in a variety of human tumor cell lines with this recombinant virus results in high levels of p16INK4A protein expression resulting in cell cycle arrest and loss of cyclin-cdk activity. Furthermore, adenoviral-mediated overexpression of wild-type p16INK4A is more toxic in cancer cells which express mutant forms of p16INK4A compared to cancer cell lines containing endogenous wild-type p16. TUNEL assay and DAPI staining following infection of MDA-MB 231 breast cancer cells with Adp16 indicate that p16INK4A-mediated cytotoxicity was associated with apoptosis. This is supported by studies demonstrating a decrease in cpp32 and cyclinB1 protein levels and induction of poly (ADP-ribose) polymerase (PARP) cleavage following infection of MDA-MB-231 cells with Adp16. These results suggest that gene therapy using Adp16 may be a promising treatment option for human cancers containing alterations in p16 expression.
Medicine Branch, National Cancer Institute, NIH, Bethesda, Maryland, MD 20892, USA.
M
M
Kim
Y
Y
Katayose
L
L
Rojanala
S
S
Shah
M
M
Sgagias
L
L
Jang
Y J
YJ
Jung
S H
SH
Lee
S G
SG
Hwang
K H
KH
Cowan
D000256:Adenoviridae; D017209:Apoptosis; D002352:Carrier Proteins / Q000096:biosynthesis* / Q000235:genetics; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism; D002460:Cell Line; D019941:Cyclin-Dependent Kinase Inhibitor p16; D015870:Gene Expression; D005822:Genetic Vectors; D006801:Humans; D016296:Mutagenesis; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D014407:Tumor Cells, Cultured
D002352:Carrier Proteins; D019941:Cyclin-Dependent Kinase Inhibitor p16; D011065:Poly(ADP-ribose) Polymerases; C505407:CASP3 protein, human; D053148:Caspase 3; D020169:Caspases