Sirtuin 2 (SIRT2) plays a major role in aging, carcinogenesis and neurodegeneration. While it has been shown that SIRT2 is a mediator of stress-induced cell death, the mechanism remains unclear. In this study, we report the role of SIRT2 in mediating radiation-induced cell death and DNA damage using mouse embryonic fibroblasts (MEFs), progenitor cells and tissues from wild-type and genomic knockout mice, and human tumor and primary cell lines as models. The presence of in cells and tissues significantly enhanced the cell's sensitivity to radiation-induced cytotoxicity by delaying the dispersion of radiation-induced γ-H2AX and 53BP1 foci. This enhanced cellular radiosensitivity correlated with reduced expression of pro-survival and DNA repair proteins, and decreased DNA repair capacities involving both homologous repair and non-homologous end joining DNA repair mechanisms compared to those in knockout (KO) and knockdown (KD) phenotypes. Together, these data suggest SIRT2 plays a critical role in mediating the radiation-induced DNA damage response, thus regulating radiation-induced cell death and survival.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8237344 | PMC |
http://dx.doi.org/10.1667/RR15282.1 | DOI Listing |
Oncotarget
January 2025
Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
Recently, combination checkpoint therapy of cancer has been recognized as producing additive as opposed to synergistic benefit due in part to positively correlated effects. The potential for uncorrelated or negatively correlated therapies to produce true synergistic benefits has been noted. Whereas the inhibitory receptors PD-1, CTLA-4, TIM-3, LAG-3, and TIGIT have been collectively characterized as exhaustion receptors, another inhibitory receptor KLRG1 was historically characterized as a senescent receptor and received relatively little attention as a potential checkpoint inhibitor target.
View Article and Find Full Text PDFGenomics Proteomics Bioinformatics
January 2025
Center for Epigenetics and Disease Prevention, Institute of Biosciences and Technology, Texas A&M University, Houston, TX 77030, USA.
Tumor-specific antigens, also known as neoantigens, have potential utility in anti-cancer immunotherapy, including immune checkpoint blockade (ICB), neoantigen-specific T cell receptor-engineered T (TCR-T), chimeric antigen receptor T (CAR-T), and therapeutic cancer vaccines (TCVs). After recognizing presented neoantigens, the immune system becomes activated and triggers the death of tumor cells. Neoantigens may be derived from multiple origins, including somatic mutations (single nucleotide variants, insertion/deletions, and gene fusions), circular RNAs, alternative splicing, RNA editing, and polymorphic microbiome.
View Article and Find Full Text PDFJ Infect Dev Ctries
December 2024
Department of Immunology, School of Medicine and Dr. Jose Eleuterio Gonzalez University Hospital, Universidad Autónoma de Nuevo León, Monterrey, Mexico.
Co-inhibitory molecules, such as cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed cell death protein 1 (PD-1), known as immune checkpoints, regulate the activity of T and myeloid cells during chronic viral infections and are well-established for their roles in cancer therapy. However, their involvement in chronic bacterial infections, particularly those caused by pathogens endemic to developing countries, such as Mycobacterium tuberculosis (Mtb), remains incompletely understood. Cytokine microenvironment determines the expression of co-inhibitory molecules in tuberculosis: Results indicate that the cytokine IL-12, in the presence of Mtb antigens, can enhance the expression of co-inhibitory molecules while preserving the effector and memory phenotypes of CD4+ T cells.
View Article and Find Full Text PDFNeoplasma
December 2024
Department of Gastrointestinal Surgery, Renmin Hospital of Wuhan University, Wuchang, Wuhan, Hubei, China.
Many lines of evidence suggest that circular RNAs (circRNAs) are closely associated with the occurrence and progression of colon cancer. The objective of this study was to investigate the regulatory effects and mechanisms of circ_0075829 on ferroptosis and immune escape in colon cancer. We utilized colon cancer cell lines and a xenograft mouse model to analyze the function of circ_0075829 in vitro and in vivo.
View Article and Find Full Text PDFNeoplasma
December 2024
Department of General Surgery/Hepatobiliary and Pancreatic Surgery, The First Affiliated Hospital of Gannan Medical University, Ganzhou, Jiangxi, China.
Esophageal squamous cell carcinoma (ESCC) has high mortality. The role and regulatory mechanism of hsa_circ_0021727 (circ_0021727) in ESCC remain largely unknown. This study focused on the undiscovered impact of circ_0021727 on cell cycle progression, apoptosis, and angiogenesis of ESCC.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!