TY - JOUR
T1 - The effect of flavopiridol on the growth of p16+ and p16- melanoma cell lines
AU - Robinson, William A.
AU - Miller, Troy L.
AU - Harrold, Elizabeth A.
AU - Bemis, Lynne T.
AU - Brady, Benjamin M.R.
AU - Nelson, R. Peter
N1 - Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2003/6
Y1 - 2003/6
N2 - Flavopiridol is the first cyclin-dependent kinase inhibitor to enter clinical trials. Flavopiridol has been shown to mimic, in part, the effect of the cell cycle control gene p16, which is frequently lost or mutated in malignant melanoma, making it an ideal candidate for targeted therapy in this disease. In these studies we investigated the effect of flavopiridol, at various concentrations, on the growth and gene expression of nine human melanoma cell lines with intact, absent or mutated p16. A cytostatic effect of flavopiridol on the growth of six melanoma cell lines with a mutated or non-expressed p16 (p16-) was seen at low concentrations of flavopiridol (mean 50% inhibitory concentration [IC50] = 12.5 nM), while the three melanoma cell lines with intact p16 (p16+) required higher concentrations (mean IC50 = 25 nM) to produce this effect. Apoptotic cell death increased with increasing concentrations of flavopiridol in both p16- and p16+ cells. Exposure of cells to high flavopiridol concentrations (>100 nM) resulted in decreased expression of genes downstream in the normal p16 cell cycle control pathway (Rb and E2F) and the anti-apoptotic gene BCL2. No change in BCL2 expression was found after exposure to IC50 concentrations of flavopiridol. These data indicate that flavopiridol in low, clinically achievable concentrations may have significant cytostatic effects, particularly in p16- melanoma cells, and may provide new molecular-based therapies for melanoma, particularly when combined with agents that target anti-apoptotic mechanisms.
AB - Flavopiridol is the first cyclin-dependent kinase inhibitor to enter clinical trials. Flavopiridol has been shown to mimic, in part, the effect of the cell cycle control gene p16, which is frequently lost or mutated in malignant melanoma, making it an ideal candidate for targeted therapy in this disease. In these studies we investigated the effect of flavopiridol, at various concentrations, on the growth and gene expression of nine human melanoma cell lines with intact, absent or mutated p16. A cytostatic effect of flavopiridol on the growth of six melanoma cell lines with a mutated or non-expressed p16 (p16-) was seen at low concentrations of flavopiridol (mean 50% inhibitory concentration [IC50] = 12.5 nM), while the three melanoma cell lines with intact p16 (p16+) required higher concentrations (mean IC50 = 25 nM) to produce this effect. Apoptotic cell death increased with increasing concentrations of flavopiridol in both p16- and p16+ cells. Exposure of cells to high flavopiridol concentrations (>100 nM) resulted in decreased expression of genes downstream in the normal p16 cell cycle control pathway (Rb and E2F) and the anti-apoptotic gene BCL2. No change in BCL2 expression was found after exposure to IC50 concentrations of flavopiridol. These data indicate that flavopiridol in low, clinically achievable concentrations may have significant cytostatic effects, particularly in p16- melanoma cells, and may provide new molecular-based therapies for melanoma, particularly when combined with agents that target anti-apoptotic mechanisms.
KW - Flavopiridol
KW - Melanoma
KW - P16
UR - http://www.scopus.com/inward/record.url?scp=0037840371&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0037840371&partnerID=8YFLogxK
U2 - 10.1097/00008390-200306000-00002
DO - 10.1097/00008390-200306000-00002
M3 - Article
C2 - 12777976
AN - SCOPUS:0037840371
SN - 0960-8931
VL - 13
SP - 231
EP - 238
JO - Melanoma research
JF - Melanoma research
IS - 3
ER -