Role of hydrogen peroxide in stress-induced programmed cell death during somatic embryogenesis in Fraxinus mandshurica

2019 ◽  
Vol 30 (3) ◽  
pp. 767-777 ◽  
Author(s):  
Ling Yang ◽  
Cheng Wei ◽  
Chao Huang ◽  
Hongnan Liu ◽  
Dongyan Zhang ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Cell Death ◽  
Somatic Embryogenesis ◽  
Programmed Cell Death ◽  
Fraxinus Mandshurica

scholarly journals Reactive oxygen species, nitric oxide and plant cell death associated with caspase-like protease activity during somatic embryogenesis in Fraxinus mandshurica

2021 ◽  
Author(s):  
Hao Wang ◽  
Dongyan Zhang ◽  
Juan Luis Fernández-Lorenzo ◽  
Hailong Shen ◽  
Ling Yang
Keyword(s):  
Nitric Oxide ◽  
Reactive Oxygen Species ◽  
Hydrogen Peroxide ◽  
Cell Death ◽  
Somatic Embryogenesis ◽  
Programmed Cell Death ◽  
Plant Growth ◽  
Growth Regulators ◽  
Protease Activity ◽  
Oxygen Species

AbstractProgrammed cell death occurs in browning explants of Fraxinus mandshurica during somatic embryogenesis, but the underlying mechanism is unclear. In this study, single cotyledons of zygotic embryos of F. mandshurica were used as explants. Mitochondrial structure and function, caspase-3-like protease activity, hydrogen peroxide metabolism, and nitric oxide accumulation induced by high concentrations of sucrose and plant growth regulators were studied. The results show that plant growth regulators induced somatic embryogenesis and also promoted explant browning. High sucrose concentrations had similar effects. High concentrations of sucrose and plant growth regulators led to the accumulation of hydrogen peroxide and nitric oxide which induced changes in mitochondrial structure and function such as modifications in mitochondrial morphology, increased membrane permeability, decreased membrane potential, and the release of cytochrome c into the cytoplasm. An increase in caspase-3-like protease activity triggered programmed cell death in some browning explant cells. During somatic embryogenesis there were increased activities of superoxide dismutase, peroxidase, and catalase, which are associated with hydrogen peroxide metabolism and jointly maintain reactive oxygen species levels. Intracellular nitric oxide synthase and nitrate reductase activities were not significantly correlated with nitric oxide content. Instead, intracellular nitric oxide may be derived from non-enzymatic reactions. Our results indicate that hydrogen peroxide and nitric oxide may function as signals, playing key roles in somatic embryogenesis and programmed cell death of explant cells of F. mandshurica. The interaction between nitric oxide and reactive oxygen species determines the occurrence of programmed cell death in explant cells; somatic embryogenesis and programmed cell death are positively regulated by hydrogen peroxide. However, the regulation of nitric oxide is complex.

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.

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