Selective growth inhibition of tumor cells by a novel histone deacetylase inhibitor, NVP-LAQ824.
We have synthesized a histone deacetylase inhibitor, NVP-LAQ824, a cinnamic hydroxamic acid, that inhibited in vitro enzymatic activities and transcriptionally activated the p21 promoter in reporter gene assays. NVP-LAQ824 selectively inhibited growth of cancer cell lines at submicromolar levels after 48-72 h of exposure, whereas higher concentrations and longer exposure times were required to retard the growth of normal dermal human fibroblasts. Flow cytometry studies revealed that both tumor and normal cells arrested in the G(2)-M phase of the cell cycle after compound treatment. However, an increased sub-G(1) population at 48 h (reminiscent of apoptotic cells) was observed only in the cancer cell line. Annexin V staining data supported our hypothesis that NVP-LAQ824 induced apoptosis in tumor and transformed cells but not in normal cells. Western blotting experiments showed an increased histone H3 and H4 acetylation level in NVP-LAQ824-treated cancer cells, suggesting that the likely in vivo target of NVP-LAQ824 was histone deacetylase(s). Finally, NVP-LAQ824 exhibited antitumor effects in a xenograft animal model. Together, our data indicated that the activity of NVP-LAQ824 was consistent with its intended mechanism of action. This novel histone deacetylase inhibitor is currently in clinical trials as an anticancer agent.
Atadja
Peter
P
Department of Oncology, Novartis Institutes for Biomedical Research, East Hanover, New Jersey, USA. peter.atadja@pharma.novartis.com
Gao
Lin
L
Kwon
Paul
P
Trogani
Nancy
N
Walker
Heather
H
Hsu
Meier
M
Yeleswarapu
Lakshmi
L
Chandramouli
Nagarajan
N
Perez
Larry
L
Versace
Richard
R
Wu
Arthur
A
Sambucetti
Lidia
L
Lassota
Peter
P
Cohen
Dalia
D
Bair
Kenneth
K
Wood
Alexander
A
Remiszewski
Stacy
S
D000818:Animals; D000970:Antineoplastic Agents / Q000633:toxicity*; D002453:Cell Cycle / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects / Q000235:genetics; D045744:Cell Line, Tumor; D003110:Colonic Neoplasms / Q000188:drug therapy* / Q000473:pathology; D004791:Enzyme Inhibitors / Q000633:toxicity; D005472:Fluorouracil / Q000627:therapeutic use; D056572:Histone Deacetylase Inhibitors; D006655:Histone Deacetylases / Q000302:isolation & purification; D006801:Humans; D006877:Hydroxamic Acids / Q000633:toxicity*; D007700:Kinetics; D008297:Male; D051379:Mice; D011401:Promoter Regions, Genetic / Q000187:drug effects / Q000235:genetics; D014183:Transplantation, Heterologous
D000970:Antineoplastic Agents; D004791:Enzyme Inhibitors; D056572:Histone Deacetylase Inhibitors; D006877:Hydroxamic Acids; C477361:LAQ824; D006655:Histone Deacetylases; D005472:Fluorouracil