scholarly journals Emerging Proviral Roles of Caspases during Lytic Replication of Gammaherpesviruses

2018 ◽  
Vol 92 (19) ◽  
Author(s):  
Tate Tabtieng ◽  
Marta M. Gaglia
Keyword(s):  
Cell Death ◽  
Programmed Cell Death ◽  
Viral Replication ◽  
Immune Evasion ◽  
Lytic Replication ◽  
Growing Body

ABSTRACTDue to their roles in the regulation of programmed cell death and inflammation, the cellular caspase proteases are considered antiviral factors. However, recent studies have revealed examples of proviral functions for caspases. Here, we review a growing body of literature on the role of caspases in promoting the replication of human gammaherpesviruses. We propose that gammaherpesviruses have evolved ways to redirect these enzymes and to use their activation to support viral replication and immune evasion.

scholarly journals A novel role of vBcl2 in the virion assembly of Kaposi's sarcoma-associated herpesvirus

2017 ◽  
pp. JVI.00914-17 ◽  
Author(s):  
Qiming Liang ◽  
Dahai Wei ◽  
Brain Chung ◽  
Kevin F. Brulois ◽  
Changrun Guo ◽  
...  
Keyword(s):  
Cell Death ◽  
Programmed Cell Death ◽  
Kaposi's Sarcoma ◽  
Lytic Replication ◽  
Tegument Protein ◽  
Virion Assembly ◽  
Amino Terminal ◽  
Infected Cells ◽  
Autophagic Activity

The viral Bcl-2 homolog (vBcl2) of Kaposi's sarcoma-associated herpesvirus (KSHV) displays efficient anti-apoptotic and anti-autophagic activity through its central BH3 domain, which functions to prolong the lifespan of virus-infected cells and ultimately enhances viral replication and latency. Independent on its anti-apoptotic and anti-autophagic activity, vBcl2 also plays an essential role in KSHV lytic replication through its amino-terminal 11-20 amino acids (aa). Here, we report a novel molecular mechanism of vBcl2-mediated regulation of KSHV lytic replication. vBcl2 specifically bound the tegument protein ORF55 through its amino-terminal 11-20aa, allowing their association with virions. Consequently, the vBcl2p peptide derived from the vBcl2 11-20aa effectively disrupted the interaction between vBcl2 and ORF55, inhibiting the incorporation of ORF55 tegument protein into virions. This study provides new insight of vBcl2's function in KSHV virion assembly that is separable from its inhibitory role of host apoptosis and autophagy.IMOPRTANCEKSHV, an important human pathogen accounting for a large percentage of virally caused cancers worldwide, has evolved a variety of stratagems for evading host immune responses to establish a life-long persistent infection. Upon viral infection, infected cells can go through a programmed cell death, including apoptosis and autophagy, that plays an effective role in anti-viral responses. To counter host response, the KSHV vBcl2 efficiently blocks apoptosis and autophagy to persist the lifespan of virus-infected cells. Besides its anti-programmed cell death activity, vBcl2 also interacts with ORF55 tegument protein for virion assembly in infected cells. Interestingly, the vBcl2p peptide disrupts the vBcl2-ORF55 interaction and effectively inhibits KSHV virion assembly. This study indicates that the KSHV vBcl2 harbors at least three genetically separable functions to modulate both host cell death signaling and virion production, and that the vBcl2p peptide can be developed as an anti-KSHV therapeutic application.

The role of programmed cell death ligand-1/ programmed cell death-1 (PD-L1/PD-1) in HPV-induced cervical cancer and potential for their use in blockade therapy

2020 ◽  
Vol 27 ◽  
Author(s):  
Lifang Zhang ◽  
Yu Zhao ◽  
Quanmei Tu ◽  
Xiangyang Xue ◽  
Xueqiong Zhu ◽  
...  
Keyword(s):  
Cervical Cancer ◽  
Cell Death ◽  
Programmed Cell Death ◽  
Immune Escape ◽  
Hypoxia Inducible Factor ◽  
Hpv Infection ◽  
Advanced Cervical Cancer ◽  
Cervical Carcinogenesis ◽  
Programmed Cell Death 1

Background: Cervical cancer induced by infection with human papillomavirus (HPV) remains a leading cause of mortality for women worldwide although preventive vaccines and early diagnosis have reduced morbidity and mortality. Advanced cervical cancer can only be treated with either chemotherapy or radiotherapy but outcomes are poor. The median survival for advanced cervical cancer patients is only 16.8 months. Methods: We undertook a structural search of peer-reviewed published studies based on 1). Characteristics of programmed cell death ligand-1/programmed cell death-1(PD-L1/PD-1) expression in cervical cancer and upstream regulatory signals of PD-L1/PD-1 expression, 2). The role of the PD-L1/PD-1 axis in cervical carcinogenesis induced by HPV infection and 3). Whether the PD-L1/PD-1 axis has emerged as a potential target for cervical cancer therapies. Results: One hundred and twenty-six published papers were included in the review, demonstrating that expression of PD-L1/PD-1 is associated with HPV-caused cancer, especially with HPV 16 and 18 which account for approximately 70% of cervical cancer cases. HPV E5/E6/E7 oncogenes activate multiple signaling pathways including PI3K/AKT, MAPK, hypoxia-inducible factor 1α, STAT3/NF-kB and MicroRNAs, which regulate PD-L1/PD-1 axis to promote HPV-induced cervical carcinogenesis. The PD-L1/PD-1 axis plays a crucial role in immune escape of cervical cancer through inhibition of host immune response. creating an "immune-privileged" site for initial viral infection and subsequent adaptive immune resistance, which provides a rationale for therapeutic blockade of this axis in HPV-positive cancers. Currently, Phase I/II clinical trials evaluating the effects of PD-L1/PD-1 targeted therapies are in progress for cervical carcinoma, which provide an important opportunity for the application of anti-PD-L1/anti-PD-1 antibodies in cervical cancer treatment. Conclusion: Recent research developments have led to an entirely new class of drugs using antibodies against the PD-L1/PD-1 thus promoting the body’s immune system to fight the cancer. The expression and roles of the PD-L1/ PD-1 axis in the progression of cervical cancer provide great potential for using PD-L1/PD-1 antibodies as a targeted cancer therapy.

scholarly journals Ozone-Induced Cell Death in Tobacco Cultivar Bel W3 Plants. The Role of Programmed Cell Death in Lesion Formation

2003 ◽  
Vol 133 (3) ◽  
pp. 1122-1134 ◽  
Author(s):  
Stefania Pasqualini ◽  
Claudia Piccioni ◽  
Lara Reale ◽  
Luisa Ederli ◽  
Guido Della Torre ◽  
...  
Keyword(s):  
Cell Death ◽  
Programmed Cell Death ◽  
Lesion Formation ◽  
Tobacco Cultivar

scholarly journals The role of reactive oxygen species and nitric oxide in programmed cell death associated with self-incompatibility

2015 ◽  
Vol 66 (10) ◽  
pp. 2869-2876 ◽  
Author(s):  
Irene Serrano ◽  
María C. Romero-Puertas ◽  
Luisa M. Sandalio ◽  
Adela Olmedilla
Keyword(s):  
Nitric Oxide ◽  
Reactive Oxygen Species ◽  
Cell Death ◽  
Programmed Cell Death ◽  
Reactive Oxygen ◽  
Oxygen Species ◽  
Self Incompatibility

scholarly journals The role of B7 family molecules in hematologic malignancy

Blood ◽  
2013 ◽  
Vol 121 (5) ◽  
pp. 734-744 ◽  
Author(s):  
Paul Greaves ◽  
John G. Gribben
Keyword(s):  
Cell Death ◽  
Programmed Cell Death ◽  
Immune Responses ◽  
Hematologic Malignancy ◽  
Surface Proteins ◽  
Cell Responses ◽  
Inducible Costimulator ◽  
Programmed Cell Death 1 ◽  
B7 Family

AbstractThe B7 family consists of structurally related, cell-surface proteins that regulate immune responses by delivering costimulatory or coinhibitory signals through their ligands. Eight family members have been identified to date including CD80 (B7-1), CD86 (B7-2), CD274 (programmed cell death-1 ligand [PD-L1]), CD273 (programmed cell death-2 ligand [PD-L2]), CD275 (inducible costimulator ligand [ICOS-L]), CD276 (B7-H3), B7-H4, and B7-H6. B7 ligands are expressed on both lymphoid and nonlymphoid tissues. The importance of the B7 family in regulating immune responses is clear from their demonstrated role in the development of immunodeficiency and autoimmune diseases. Manipulation of the signals delivered by B7 ligands shows great potential in the treatment of cancers including leukemias and lymphomas and in regulating allogeneic T-cell responses after stem cell transplantation.

scholarly journals Calcium Signaling in Plant Programmed Cell Death

Cells ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 1089
Author(s):  
Huimin Ren ◽  
Xiaohong Zhao ◽  
Wenjie Li ◽  
Jamshaid Hussain ◽  
Guoning Qi ◽  
...  
Keyword(s):  
Cell Death ◽  
Programmed Cell Death ◽  
Abiotic Stresses ◽  
Animal Studies ◽  
Future Research ◽  
Significant Progress ◽  
Biotic And Abiotic Stresses ◽  
Stress Perception ◽  
The Past

Programmed cell death (PCD) is a process intended for the maintenance of cellular homeostasis by eliminating old, damaged, or unwanted cells. In plants, PCD takes place during developmental processes and in response to biotic and abiotic stresses. In contrast to the field of animal studies, PCD is not well understood in plants. Calcium (Ca2+) is a universal cell signaling entity and regulates numerous physiological activities across all the kingdoms of life. The cytosolic increase in Ca2+ is a prerequisite for the induction of PCD in plants. Although over the past years, we have witnessed significant progress in understanding the role of Ca2+ in the regulation of PCD, it is still unclear how the upstream stress perception leads to the Ca2+ elevation and how the signal is further propagated to result in the onset of PCD. In this review article, we discuss recent advancements in the field, and compare the role of Ca2+ signaling in PCD in biotic and abiotic stresses. Moreover, we discuss the upstream and downstream components of Ca2+ signaling and its crosstalk with other signaling pathways in PCD. The review is expected to provide new insights into the role of Ca2+ signaling in PCD and to identify gaps for future research efforts.

Sign in / Sign up

Export Citation Format

Share Document