Abstract |
Primary effusion lymphoma (PEL) is a refractory malignancy caused by human herpes virus 8 (HHV-8) in immunocompromised individuals. The tumor cells of PEL are characterized by constitutive NF-kappaB activation. Dehydroxymethylepoxyquinomicin (DHMEQ) is a new NF-kappaB inhibitor and is effective on various tumor cells with constitutively activated NF-kappaB. Thus, in search for a new therapeutic modality of PEL, we examined the effect of DHMEQ on PEL cells. We confirmed constitutive activation of NF-kappaB with subcomponents of p50 and p65 in PEL cell lines. DHMEQ quickly and transiently abrogated NF-kappaB activation and reduced the cell viability in dose- and time-dependent manners, inducing apoptosis through activation of both mitochondrial and membrane pathways. Array analysis revealed that DHMEQ down-regulated expression levels of NF-kappaB target genes, such as interleukin-6 ( IL6), Myc, chemokine (C-C motif) receptor 5 (CCR5) and NF-kappaB1, whereas it up-regulated expression levels of some genes involved in apoptosis, and cell cycle arrest. DHMEQ did not reactivate HHV-8 lytic genes, indicating that NF-kappaB inhibition by DHMEQ did not induce virus replication. DHEMQ rescued CB-17 SCID mice xenografted with PEL cells, reducing the gross appearance of effusion. Thus, DHMEQ transiently abrogated the NF-kappaB activation, irreversibly triggering the apoptosis cascade without HHV-8 reactivation. In addition, DHMEQ could rescue the PEL-xenograft mice. Therefore, we suggest DHMEQ as a promising candidate for molecular target therapy of the PEL.
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Authors | Nazanin Dabaghmanesh, Aiko Matsubara, Ariko Miyake, Kazumi Nakano, Takaomi Ishida, Harutaka Katano, Ryoichi Horie, Kazuo Umezawa, Toshiki Watanabe |
Journal | Cancer science
(Cancer Sci)
Vol. 100
Issue 4
Pg. 737-46
(Apr 2009)
ISSN: 1349-7006 [Electronic] England |
PMID | 19469019
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Antineoplastic Agents
- Benzamides
- Cyclohexanones
- NF-kappa B
- dehydroxymethylepoxyquinomicin
- Caspase 3
- Caspase 8
- Caspase 9
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Topics |
- Antineoplastic Agents
(pharmacology)
- Apoptosis
(drug effects)
- Benzamides
(pharmacology)
- Caspase 3
(metabolism)
- Caspase 8
(metabolism)
- Caspase 9
(metabolism)
- Cell Death
(drug effects)
- Cell Line, Tumor
- Cell Survival
(drug effects)
- Cyclohexanones
(pharmacology)
- Dose-Response Relationship, Drug
- Enzyme Activation
(drug effects)
- HeLa Cells
- Herpesvirus 8, Human
(metabolism)
- Humans
- In Situ Nick-End Labeling
- Jurkat Cells
- K562 Cells
- Lymphoma, Primary Effusion
(drug therapy, prevention & control, virology)
- NF-kappa B
(antagonists & inhibitors)
- Time Factors
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