Induction of caspase-independent apoptotic-like cell death of mouse mammary tumor TA3Ha cells in vitro and reduction of their lethality in vivo by the novel chemotherapeutic agent GIT-27NO.
The new chemical entity GIT-27NO was created by the covalent linkage of a NO moiety to the anti-inflammatory isoxazoline VGX-1027. The compound has been shown to possess powerful anticancer effects both in vitro and in vivo. However, its effects on nonsolid and metastatic forms of tumors have not yet been investigated. We have studied the effects of GIT-27NO on the highly invasive mouse mammary TA3Ha cell line in vitro and in vivo. In contrast to the conventional exogenous NO donor sodium nitroprusside, GIT-27NO successfully enhanced intracellular NO concentration in TA3Ha cells. Intracellular accumulation of NO was followed by marked decrease in TA3Ha cell viability accompanied by typical apoptotic features. Interestingly, inverted membrane phosphatidylserine residues, reduced volume of nucleus, condensed chromatin, and terminal fragmentation of DNA were associated with inhibited caspase-3 activity and transcription of the genes encoding caspase-3, -8, and -9. In parallel, GIT-27NO rapidly but transiently prevented the loss of p53 through phosphorylation on Ser 20 and provided the necessary signals for the execution of downstream processes without p53 de novo synthesis. The caspase-independent apoptotic-like death process triggered by GIT-27NO could be mediated by markedly down-regulated expression of the antiapoptotic Bcl-2 molecule observed in TA3Ha cells exposed to GIT-27NO. In agreement with these in vitro data, GIT-27NO efficiently suppressed the growth of the ascites form and associated lethality of tumor induced by TA3Ha cells in mice.
Mijatovic
Sanja
S
Department of Immunology, Institute for Biological Research Sinisa Stankovic, Belgrade University, 11000 Belgrade, Serbia.
Maksimovic-Ivanic
Danijela
D
Timotijevic
Gordana
G
Miljkovic
Djordje
D
Donia
Marco
M
Libra
Massimo
M
Coco
Marinella
M
McCubrey
James
J
Al-Abed
Yousef
Y
Korac
Aleksandra
A
Stosic-Grujicic
Stanislava
S
Nicoletti
Ferdinando
F
D000085:Acetates / Q000494:pharmacology; D000818:Animals; D053148:Caspase 3 / Q000096:biosynthesis; D053181:Caspase 8 / Q000096:biosynthesis; D053453:Caspase 9 / Q000096:biosynthesis; D020169:Caspases / Q000378:metabolism; D016923:Cell Death / Q000187:drug effects; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D015536:Down-Regulation; D005260:Female; D008325:Mammary Neoplasms, Experimental / Q000188:drug therapy*; D051379:Mice; D009569:Nitric Oxide / Q000378:metabolism; D010069:Oxadiazoles / Q000627:therapeutic use*; D010080:Oxazoles / Q000494:pharmacology / Q000627:therapeutic use*; D010534:Peritoneal Neoplasms / Q000517:prevention & control; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism
C518641:3-phenyl-4,5-dihydro-5-isoxazole acetic acid; D000085:Acetates; C550245:GIT 27NO compound; D010069:Oxadiazoles; D010080:Oxazoles; D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53; D009569:Nitric Oxide; D053148:Caspase 3; D053181:Caspase 8; D053453:Caspase 9; D020169:Caspases