Acetyl‐11‐keto‐β‐boswellic acid triggers premature senescence via induction of DNA damage accompanied by impairment of DNA repair genes in hepatocellular carcinoma cells
            in vitro
            and
            in vivo

Infections with Mycobacterium tuberculosis, the causative agent of tuberculosis, are difficult to treat using currently available chemotherapeutics. Clinicians agree on the urgent need for novel drugs to treat tuberculosis. In this mini review, we summarize data that prompts the consideration of DNA repair-associated proteins as targets for the development of new antitubercular compounds. We discuss data, including gene expression data, that highlight the importance of DNA repair genes during the pathogenic cycle as well as after exposure to antimicrobials currently in use. Specifically, we report experiments on determining the essentiality of DNA repair-related genes. We report the availability of protein crystal structures and summarize discovered protein inhibitors. Further, we describe phenotypes of available gene mutants of M. tuberculosis and model organisms Mycobacterium bovis and Mycobacterium smegmatis. We summarize experiments regarding the role of DNA repair-related proteins in pathogenesis and virulence performed both in vitro and in vivo during the infection of macrophages and animals. We detail the role of DNA repair genes in acquiring mutations, which influence the rate of drug resistance acquisition.

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MAPK dependence of DNA damage repair: ionizing radiation and the induction of expression of the DNA repair genes XRCC1 and ERCC1 in DU145 human prostate carcinoma cells in a MEK1/2 dependent fashion

International Journal of Radiation Biology ◽

10.1080/09553000110069317 ◽

2001 ◽

Vol 77 (10) ◽

pp. 1067-1078 ◽

Cited By ~ 56

Author(s):

A. Yacoub ◽

Jong Sung Park ◽

Liang Qiao ◽

P. Dent ◽

M. P. Hagan

Keyword(s):

Dna Damage ◽

Dna Repair ◽

Ionizing Radiation ◽

Prostate Carcinoma ◽

Carcinoma Cells ◽

Human Prostate ◽

Dna Repair Genes ◽

Damage Repair ◽

Human Prostate Carcinoma ◽

Repair Genes

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METTL3 Promotes the Resistance of Glioma to Temozolomide via Increasing MGMT and ANPG in a m6A Dependent Manner

Frontiers in Oncology ◽

10.3389/fonc.2021.702983 ◽

2021 ◽

Vol 11 ◽

Author(s):

Jia Shi ◽

Gang Chen ◽

Xuchen Dong ◽

Haoran Li ◽

Suwen Li ◽

...

Keyword(s):

Dna Repair ◽

Clinical Treatment ◽

Current Understanding ◽

Therapeutic Resistance ◽

Limiting Factor ◽

Dependent Manner ◽

Dna Repair Genes ◽

Repair Genes

Acquired chemoresistance is a major limiting factor in the clinical treatment of glioblastoma (GBM). However, the mechanism by which GBM acquires therapeutic resistance remains unclear. Here, we aimed to investigate whether METTL3-mediated N6-methyladenosine (m6A) modification contributes to the temozolomide (TMZ) resistance in GBM. We demonstrated that METTL3 METTL3-mediated m6A modification were significantly elevated in TMZ-resistant GBM cells. Functionally, METTL3 overexpression impaired the TMZ-sensitivity of GBM cells. In contrast, METTL3 silencing or DAA-mediated total methylation inhibition improved the sensitivity of TMZ-resistant GBM cells to TMZ in vitro and in vivo. Furthermore, we found that two critical DNA repair genes (MGMT and APNG) were m6A-modified by METTL3, whereas inhibited by METTL3 silencing or DAA-mediated total methylation inhibition, which is crucial for METTL3-improved TMZ resistance in GBM cells. Collectively, METTL3 acts as a critical promoter of TMZ resistance in glioma and extends the current understanding of m6A related signaling, thereby providing new insights into the field of glioma treatment.

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RNA methyltransferase NSUN2 promotes growth of hepatocellular carcinoma cells by regulating fizzy‐related‐1 in vitro and in vivo

The Kaohsiung Journal of Medical Sciences ◽

10.1002/kjm2.12430 ◽

2021 ◽

Author(s):

Chun‐Tao Zhai ◽

Yi‐Cheng Tian ◽

Zu‐Xiong Tang ◽

Long‐Jiang Shao

Keyword(s):

Hepatocellular Carcinoma ◽

Carcinoma Cells ◽

Hepatocellular Carcinoma Cells

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Sirt1 deacetylates and stabilizes p62 to promote hepato-carcinogenesis

Cell Death and Disease ◽

10.1038/s41419-021-03666-z ◽

2021 ◽

Vol 12 (4) ◽

Author(s):

Lifeng Feng ◽

Miaoqin Chen ◽

Yiling Li ◽

Muchun Li ◽

Shiman Hu ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Overall Survival ◽

Cell Growth ◽

Knockout Mice ◽

Liver Tumors ◽

Underlying Mechanism ◽

Carcinoma Cells ◽

Conditional Knockout

Abstractp62/SQSTM1 is frequently up-regulated in many cancers including hepatocellular carcinoma. Highly expressed p62 promotes hepato-carcinogenesis by activating many signaling pathways including Nrf2, mTORC1, and NFκB signaling. However, the underlying mechanism for p62 up-regulation in hepatocellular carcinoma remains largely unclear. Herein, we confirmed that p62 was up-regulated in hepatocellular carcinoma and its higher expression was associated with shorter overall survival in patients. The knockdown of p62 in hepatocellular carcinoma cells decreased cell growth in vitro and in vivo. Intriguingly, p62 protein stability could be reduced by its acetylation at lysine 295, which was regulated by deacetylase Sirt1 and acetyltransferase GCN5. Acetylated p62 increased its association with the E3 ligase Keap1, which facilitated its poly-ubiquitination-dependent proteasomal degradation. Moreover, Sirt1 was up-regulated to deacetylate and stabilize p62 in hepatocellular carcinoma. Additionally, Hepatocyte Sirt1 conditional knockout mice developed much fewer liver tumors after Diethynitrosamine treatment, which could be reversed by the re-introduction of exogenous p62. Taken together, Sirt1 deacetylates p62 at lysine 295 to disturb Keap1-mediated p62 poly-ubiquitination, thus up-regulating p62 expression to promote hepato-carcinogenesis. Therefore, targeting Sirt1 or p62 is a reasonable strategy for the treatment of hepatocellular carcinoma.

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Patients with Systemic Sclerosis Present Increased DNA Damage Differentially Associated with DNA Repair Gene Polymorphisms

The Journal of Rheumatology ◽

10.3899/jrheum.130376 ◽

2014 ◽

Vol 41 (3) ◽

pp. 458-465 ◽

Cited By ~ 11

Author(s):

Gustavo Martelli Palomino ◽

Carmen L. Bassi ◽

Isabela J. Wastowski ◽

Danilo J. Xavier ◽

Yara M. Lucisano-Valim ◽

...

Keyword(s):

Dna Damage ◽

Dna Repair ◽

Systemic Sclerosis ◽

Blood Cells ◽

Gene Polymorphisms ◽

Peripheral Blood Cells ◽

Dna Repair Genes ◽

Repair Gene ◽

Dna Repair Gene ◽

Repair Genes

Objective.Patients with systemic sclerosis (SSc) exhibit increased toxicity when exposed to genotoxic agents. In our study, we evaluated DNA damage and polymorphic sites in 2 DNA repair genes (XRCC1Arg399Gln andXRCC4Ile401Thr) in patients with SSc.Methods.A total of 177 patients were studied for DNA repair gene polymorphisms. Fifty-six of them were also evaluated for DNA damage in peripheral blood cells using the comet assay.Results.Compared to controls, the patients as a whole or stratified into major clinical variants (limited or diffuse skin involvement), irrespective of the underlying treatment schedule, exhibited increased DNA damage.XRCC1(rs: 25487) andXRCC4(rs: 28360135) allele and genotype frequencies observed in patients with SSc were not significantly different from those observed in controls; however, theXRCC1Arg399Gln allele was associated with increased DNA damage only in healthy controls and theXRCC4Ile401Thr allele was associated with increased DNA damage in both patients and controls. Further, theXRCC1Arg399Gln allele was associated with the presence of antinuclear antibody and anticentromere antibody. No association was observed between these DNA repair gene polymorphic sites and clinical features of patients with SSc.Conclusion.These results corroborate the presence of genomic instability in SSc peripheral blood cells, as evaluated by increased DNA damage, and show that polymorphic sites of theXRCC1andXRCC4DNA repair genes may differentially influence DNA damage and the development of autoantibodies.

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