Sangivamycin induces apoptosis by suppressing Erk signaling in primary effusion lymphoma cells

Wakao, Kazufumi; Watanabe, Tadashi; Takadama, Tadatoshi; Ui, Sadaharu; Shigemi, Zenpei; Kagawa, Hiroyasu; Higashi, Chizuka; Ohga, Rie; Taira, Takahiro; Fujimuro, Masahiro

doi:10.1016/j.bbrc.2014.01.017

Cited by 29 publications

(30 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For quantification of virus production, KSHV virions in culture supernatant were quantified as previously described 39, 40 . Briefly, iVero cells (iVero-WT, iVero-ΔORF34 or iVero-Revertant) were treated with 8 μg/mL of doxycycline and 1.5 mM of NaB for 48 hours to induce to lytic replication and production of recombinant KSHV, and culture supernatants were harvested.…”

Section: Methodsmentioning

confidence: 99%

Kaposi’s sarcoma-associated herpesvirus ORF34 is essential for late gene expression and virus production

Nishimura

Watanabe

Yagi

et al. 2017

Sci Rep

Self Cite

108

View full text Add to dashboard Cite

Kaposi’s sarcoma-associated herpesvirus (KSHV) is the causative agent of Kaposi’s sarcoma, primary effusion lymphoma, and multicentric Castleman’s disease. KSHV establishes a life-long infection in its host and alternates between a latent and lytic infection state. During lytic infection, lytic-related genes are expressed in a temporal manner and categorized as immediate early, early, and late gene transcripts. ORF34 is an early-late gene that interacts with several viral transcription-associated factors, however its physiological importance remains poorly understood. Here, we investigated the role of ORF34 during KSHV infection by generating ORF34-deficient KSHV, using a bacterial artificial chromosome system. Our results reveal that ORF34-deficient KSHV exhibited significantly attenuated late gene expression and viral production but did not affect viral DNA replication. ORF34 interacted with transcription factors ORF18, ORF24, ORF31, and ORF66, and a novel ORF34-interaction partner, ORF23. The C-terminal region of ORF34 was important for interaction with ORF24 and viral production. Our data support a model, in which ORF34 serves as a hub for recruiting a viral transcription complex to ORF24 to promote late viral gene expression.

show abstract

Section: Methodsmentioning

confidence: 99%

Kaposi’s sarcoma-associated herpesvirus ORF34 is essential for late gene expression and virus production

Nishimura

Watanabe

Yagi

et al. 2017

Sci Rep

Self Cite

108

View full text Add to dashboard Cite

show abstract

“…Cells were seeded on 96-well plates at 2.5x10 4 cells/well in 100 µl of medium with or without various concentrations of DAS, DAD or DAT and then incubated at 37˚C for 24 h. The number of viable cells was estimated using a Cell Counting kit-8 (Dojindo, Tokyo, Japan) as described previously (27). The optical density at 450 nm of each sample was measured using a microplate spectrophotometer (Tecan m200; Tecan, Kanagawa, Japan) and expressed as a percentage of the value in untreated cells (defined as 100%).…”

Section: Methodsmentioning

confidence: 99%

Diallyl trisulfide induces apoptosis by suppressing NF-κB signaling through destabilization of TRAF6 in primary effusion lymphoma

Shigemi

Furukawa

Hosokawa

et al. 2015

International Journal of Oncology

Self Cite

View full text Add to dashboard Cite

Abstract. The allyl sulfides, including diallyl sulfide (DAS), diallyl disulfide (DAD), and diallyl trisulfide (DAT), contained in garlic and members of the Allium family, have a variety of pharmacological activities. Therefore, allyl sulfides have been evaluated as potential novel chemotherapeutic agents. Here, we found that DAT inhibited nuclear factor-κB (NF-κB) signaling and induced apoptosis in primary effusion lymphoma (PEL), a subtype of non-Hodgkin's B-cell lymphoma caused by Kaposi's sarcoma-associated herpesvirus (KSHV). We examined the cytotoxic effects of DAS, DAD and DAT on PEL cells. DAT significantly reduced the viability of PEL cells compared with uninfected B-lymphoma cells, and induced the apoptosis of PEL cells by activating caspase-9. DAT induced stabilization of IκBα, and suppressed NF-κB transcriptional activity in PEL cells. We examined the mechanism underlying DAT-mediated IκBα stabilization. The results indicated that DAT stabilized IκBα by inhibiting the phosphorylation of IκBα by the IκB kinase (IKK) complex. Furthermore, DAT induced proteasomal degradation of TRAF6, and DAT suppressed IKKβ-phosphorylation through downregulation of TRAF6. It is known that activation of NF-κB is essential for survival of PEL cells. In fact, the NF-κB inhibitor BAY11-7082 induced apoptosis in PEL cells. In addition, DAT suppressed the production of progeny virus from PEL cells. The administration of DAT suppressed the development of PEL cells and ascites in SCID mice xenografted with PEL cells. These findings provide evidence that DAT has antitumor activity against PEL cells in vitro and in vivo, suggesting it to be a novel therapeutic agent for the treatment of PEL. IntroductionPrimary effusion lymphoma (PEL, also termed body-cavitybased lymphoma) is a malignant B-cell lymphoma caused by Kaposi's sarcoma-associated herpesvirus (KSHV, also named HHV-8) in immunosuppressed individuals, such as AIDS patients or those that have undergone organ transplantation (1,2). PEL is a subtype of non-Hodgkin's lymphoma and is characterized by lymphomatous effusions of pleural and abdominal cavities. KSHV is a rhadinovirus of the γ-herpesvirus subfamily and is closely related to herpesvirus Saimiri and Epstein-Barr virus (EBV). KSHV is the causative agent of Kaposi's sarcoma and AIDS-related lymphoproliferative disorders, such as PEL and multicentric Castleman's disease (3). Similar to other herpesviruses, KSHV has two life cycles (latency and lytic replication). The KSHV genome circularizes and forms a double-stranded DNA, the episome, in the nucleus of PEL cells during latent infection. To establish a latent infection, KSHV expresses several viral genes, including latency-associated nuclear antigen (LANA), v-FLIP, v-cyclin, kaposin and microRNAs, in PEL cells. LANA is required for the replication and maintenance of viral DNA, and contributes to KSHV-associated oncogenesis through interaction with cellular molecules, such as p53, Rb and GSK-3. These viral proteins and RNA manipulate cellular signaling pathways, includ...

show abstract

“…For quantification of virus production, KSHV virions in culture supernatant were quantified as previously described (20, 40, 41). Briefly, iSLK and iVero cells (iSLK-WT, iSLK-ΔORF66, iVero-WT, or iVero-ΔORF66) were treated with Sodium Butyrate (NaB) and doxycycline (iSLK; NaB 0.75 mM/ Dox 4 μg/mL, iVero; NaB 1.5 mM/ Dox 8 μg/mL) for 72 hours to induce to lytic replication and production of recombinant KSHV, and culture supernatants were harvested.…”

Section: Methodsmentioning

confidence: 99%

Kaposi’s sarcoma-associated herpesvirus ORF66 is essential for late gene expression and virus production via interaction with ORF34

Watanabe

Nishimura

Izumi

et al. 2019

Preprint

Self Cite

View full text Add to dashboard Cite

25Kaposi's sarcoma-associated herpesvirus (KSHV) is closely 26 associated with B-cell and endothelial cell malignancies. After the initial 27 infection, KSHV retains its viral genome in the nucleus of the host cell and 28 establishes a lifelong latency. During lytic infection, KSHV encoded lytic-related 29 proteins are expressed in a sequential manner and are classified as immediate 30 early, early, and late gene transcripts. The transcriptional initiation of KSHV late 31 genes is thought to require the complex formation of the virus specific pre-32 initiation complex (vPIC), which may consist of at least 6 transcription factors 33 (ORF18, 24, 30, 31, 34, and 66). However, the functional role of ORF66 in vPIC 34 during KSHV replication remains largely unclear. Here, we generated ORF66-35 deficient KSHV using a BAC system to evaluate its role during viral replication. 36While ORF66-deficient KSHV demonstrated mainly attenuated late gene 37 expression and decreased viral production, viral DNA replication was 38 unaffected. CHIP analysis showed that ORF66 bound to the promoters of late 39 gene (K8.1), but did not to those of latent gene (ORF72), immediate early gene 40 (ORF16) and early gene (ORF46/47). Furthermore, we found that three highly 41 conserved C-X-X-C sequences and a conserved leucine-repeat in the C-42 terminal region of ORF66 were essential for interaction with ORF34 and viral 43 production. The interaction between ORF66 and ORF34 occurred in a zinc-44 dependent manner. Our data support a model, in which ORF66 serves as a 45 critical vPIC component to promote late viral gene expression and viral 46 production. 47 IMPORTANCE 49 KSHV ORF66, a late gene product, and vPIC are thought to contribute 50 significantly to late gene expression during the lytic replication. However, the 51 physiological importance of ORF66 in terms of viral replication and vPIC 52 formation remains poorly understood. Therfore, we generated a ORF66-53 deficient BAC clone and evaluated its viral replication. Results showed that 54 ORF66 played a critical role in virus production and the transcription of L genes. 55To our knowledge, this is the first report showing ORF66 function in virus 56 replication using ORF66-deficient KSHV. We also clarified that ORF66 57 interacted with the transcription start site of K8.1 gene, a late gene. 58 Furthermore, we identified the ORF34-binding motifs in the ORF66 C-terminus: 59 three C-X-X-C sequences and a leucine-repeat sequence, which are highly 60 conserved among -and -herpesviruses. Our study provides insights into the 61 regulatory mechanisms of not only the late gene expression of KSHV but also 62 those of other herpesviruses. 63 64 65 replication. Finally, the transcriptional products of L genes, contribute to viral 90 particle formation by its encoding viral structure proteins (15). 91The viral pre-initiation complex (vPIC) has recently been proposed to 92 regulate L gene expression(16). vPIC is composed of several viral proteins 93 conserved among -and -herpesviruses (17), and has f...

show abstract

Sangivamycin induces apoptosis by suppressing Erk signaling in primary effusion lymphoma cells

Cited by 29 publications

References 20 publications

Kaposi’s sarcoma-associated herpesvirus ORF34 is essential for late gene expression and virus production

Kaposi’s sarcoma-associated herpesvirus ORF34 is essential for late gene expression and virus production

Diallyl trisulfide induces apoptosis by suppressing NF-κB signaling through destabilization of TRAF6 in primary effusion lymphoma

Kaposi’s sarcoma-associated herpesvirus ORF66 is essential for late gene expression and virus production via interaction with ORF34

Contact Info

Product

Resources

About