title: JS-K, a GST-activated nitric oxide generator, induces DNA double-strand breaks, activates DNA damage response pathways, and induces apoptosis in vitro and in vivo in human multiple myeloma cells.
abstract: Here we investigated the cytotoxicity of JS-K, a prodrug designed to release nitric oxide (NO(*)) following reaction with glutathione S-transferases, in multiple myeloma (MM). JS-K showed significant cytotoxicity in both conventional therapy-sensitive and -resistant MM cell lines, as well as patient-derived MM cells. JS-K induced apoptosis in MM cells, which was associated with PARP, caspase-8, and caspase-9 cleavage; increased Fas/CD95 expression; Mcl-1 cleavage; and Bcl-2 phosphorylation, as well as cytochrome c, apoptosis-inducing factor (AIF), and endonuclease G (EndoG) release. Moreover, JS-K overcame the survival advantages conferred by interleukin-6 (IL-6) and insulin-like growth factor 1 (IGF-1), or by adherence of MM cells to bone marrow stromal cells. Mechanistic studies revealed that JS-K-induced cytotoxicity was mediated via NO(*) in MM cells. Furthermore, JS-K induced DNA double-strand breaks (DSBs) and activated DNA damage responses, as evidenced by neutral comet assay, as well as H2AX, Chk2 and p53 phosphorylation. JS-K also activated c-Jun NH(2)-terminal kinase (JNK) in MM cells; conversely, inhibition of JNK markedly decreased JS-K-induced cytotoxicity. Importantly, bortezomib significantly enhanced JS-K-induced cytotoxicity. Finally, JS-K is well tolerated, inhibits tumor growth, and prolongs survival in a human MM xenograft mouse model. Taken together, these data provide the preclinical rationale for the clinical evaluation of JS-K to improve patient outcome in MM.
authors: Jerome Lipper Multiple Myeloma Center, Department of Medical Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA 02115, USA.
authors: Tanyel
authors: T
authors: Kiziltepe
authors: Teru
authors: T
authors: Hideshima
authors: Kenji
authors: K
authors: Ishitsuka
authors: Enrique M
authors: EM
authors: Ocio
authors: Noopur
authors: N
authors: Raje
authors: Laurence
authors: L
authors: Catley
authors: Chun-Qi
authors: CQ
authors: Li
authors: Laura J
authors: LJ
authors: Trudel
authors: Hiroshi
authors: H
authors: Yasui
authors: Sonia
authors: S
authors: Vallet
authors: Jeffery L
authors: JL
authors: Kutok
authors: Dharminder
authors: D
authors: Chauhan
authors: Constantine S
authors: CS
authors: Mitsiades
authors: Joseph E
authors: JE
authors: Saavedra
authors: Gerald N
authors: GN
authors: Wogan
authors: Larry K
authors: LK
authors: Keefer
authors: Paul J
authors: PJ
authors: Shami
authors: Kenneth C
authors: KC
authors: Anderson
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D001391:Azo Compounds / Q000494:pharmacology*; D002455:Cell Division / Q000187:drug effects; D045744:Cell Line, Tumor; D004249:DNA Damage; D004273:DNA, Neoplasm / Q000187:drug effects / Q000235:genetics; D006801:Humans; D007150:Immunohistochemistry; D009101:Multiple Myeloma / Q000235:genetics* / Q000473:pathology; D010879:Piperazines / Q000494:pharmacology*
chemical_list: D001391:Azo Compounds; D004273:DNA, Neoplasm; C474958:O(2)-(2,4-dinitrophenyl) 1-((4-ethoxycarbonyl)piperazin-1-yl)diazen-1-ium-1,2-diolate; D010879:Piperazines