ku86

We wish to retract the article titled "Ku86 Variant Expression and Function in Multiple Myeloma Cells Is Associated with Increased Sensitivity to DNA Damage" by Yu-Tzu Tai, Gerrard Teoh, Boris Lin, Faith E. Davies, Dharminder Chauhan, Steven P. Treon, Noopur Raje, Teru Hideshima, Yoshihito Shima, Klaus Podar, and Kenneth C. Anderson, The Journal of Immunology, 2000, 165:6347-6355. There are concerns about the reliability of certain data, arising from errors in the assembly of Figs. 1B, 1D. The authors have concluded that these figures cannot be used to support the conclusions of the article...

Ischemic cerebrovascular disease is the main cause of disability due to stroke. This study aimed to investigate the function of miR-1224 in OGD/R-induced hippocampal neuron apoptosis, as well as the regulatory mechanism of miR-1224 in ischemic cerebrovascular disease. The oxygen-glucose deprivation/reperfusion (OGD/R) model of primary mouse hippocampal neurons was established. RT-qPCR detected miR-1224, Ku70 and Ku86 levels. Western blotting was applied to measure the expression of Ku70/86 and apoptosis related proteins...

Adenovirus (Ad) early region 4 (E4) mutants activate cellular DNA damage responses (DDRs) that include non-homologous end joining (NHEJ) pathways mediated by the DNA repair kinase DNA-PK and its associated factors Ku70/Ku86. NHEJ results in concatenation of the viral linear double-stranded DNA genome and inhibits a productive infection. E4 proteins normally prevent activation of cellular DDRs in wild-type Ad type 5 (Ad5) infections, thereby promoting efficient viral growth. The purpose of this study was to evaluate the factors that govern DNA-PK activation during adenovirus infection...

Drug resistance and disease recurrence are important contributors for the poor prognosis of glioblastoma multiforme (GBM). Temozolomide (TMZ), the standard chemotherapy for GBM treatment, can methylate DNA and cause the formation of double-strand breaks (DSBs). X-ray repair cross complementing 5 (XRCC5), also known as Ku80 or Ku86, is required for the repair of DSBs. The present study identified novel determinants that sensitize cells to TMZ, using an array-based short hairpin (sh)RNA library. Then, cBioportal, Oncomine, and R2 databases were used to analyze the association between gene expression levels and clinical characteristics...

Cancer metastasis is the major cause of death from cancer (Massague and Obenauf, 2016; Steeg, 2016). The extensive genetic heterogeneity and cellular plasticity of metastatic tumors set a prime barrier for the current cancer treatment protocols (Boumahdi and de Sauvage, 2020). In addition, acquired therapy resistance has become an insurmountable obstacle that abolishes the beneficial effects of numerous anti-cancer regimens (De Angelis et al., 2019; Boumahdi and de Sauvage, 2020). Here we report that deficiency of Ku leads to the exploitation of host cells in human cancer cell line models...

The biological effects of ionizing radiation, especially those of sparsely ionizing radiations like X-ray and γ-ray, are generally reduced as the dose rate is reduced. This phenomenon is known as 'the dose-rate effect'. The dose-rate effect is considered to be due to the repair of DNA damage during irradiation but the precise mechanisms for the dose-rate effect remain to be clarified. Ku70, Ku86 and DNA-dependent protein kinase catalytic subunit (DNA-PKcs) are thought to comprise the sensor for DNA double-strand break (DSB) repair through non-homologous end joining (NHEJ)...

We evaluated the potential effects of ATO in different pediatric SHH-MB cell lines (ONS-76: TP53-wild type; DAOY and UW402: TP53-mutated). MB cell lines molecular subgroup was confirmed and TP53 mutations were validated. Cell viability, clonogenicity and apoptosis were evaluated after ATO treatment at different concentrations (1-16 µM) alone or combined with irradiation doses (0.5, 1, 2 and 4 Gy). Rad51 and Ku86 proteins were evaluated by WB. ATO treatment reduced cell viability for all SHH-MB cell lines...

With its high efficiency for site-specific genome editing and easy manipulation, the clustered regularly interspaced short palindromic repeats (CRISPR)/ CRISPR associated protein 9 (CAS9) system has become the most widely used gene editing technology in biomedical research. In addition, significant progress has been made for the clinical development of CRISPR/CAS9 based gene therapies of human diseases, several of which are entering clinical trials. Here we report that CAS9 protein can function as a genome mutator independent of any exogenous guide RNA (gRNA) in human cells, promoting genomic DNA double-stranded break (DSB) damage and genomic instability...

Drug resistance and recurrence are significant contributors to the poor prognosis of serous ovarian cancer (SOC). Radiotherapy is primarily used for the treatment of cancer recurrence; however, it is rarely applied in cases of SOC. Ku86, also known as XRCC5(X-ray repair cross complementing 5), has rarely been reported in the radiotherapy of SOC. Therefore, this study aimed to investigate the role of Ku86 in the development of SOC and in radiotherapy sensitivity induced by X-ray. In vitro experiments and database analysis showed significantly elevated expression of Ku86 in SOC...

BACKGROUND/AIMS: Hepatocellular carcinoma (HCC) is the fifth most common malignancy and most frequently develops in patients with cirrhosis. Surveillance strategies are recommended in high-risk groups because early detection of small lesions improves the likelihood of curative treatment. This study investigated the prospective clinical significance of serum levels of anti-Ku86 and plasma levels of lamin B1and vimentin as early markers of HCC. METHODS: We recruited 74 patients at Assiut University Hospital-37 with HCC and 37 with chronic liver disease (liver cirrhosis patients)-and 36 age- and sex-matched healthy controls...

OBJECTIVE: The aim of this study was to observe the effect of Ku86 on cellular senescence and apoptosis induced by various doses of ionizing radiation in human umbilical vein endothelial cells (HUVECs). METHODS: Senescence-associated β-galactosidase activity was detected to evaluate cell senescence. Apoptosis was determined by flow cytometry and a caspase enzyme determination kit. p16Ink4a , Sirt1, superoxide dismutase 2 (SOD2), xanthine oxidase (XOD), and Bcl-2 protein expression levels were measured by western blotting...

Radiotherapy plays an important therapeutic role in esophageal cancer (EC). However, acquired radioresistance impairs the efficacy of radiotherapy, often leading to treatment failure. Therefore, it is important to develop novel radiosensitizers to enhance the clinical treatment of EC. The purpose of this study was to investigate the role of artesunate (ART) on radiosensitivity of human EC cell line TE-1. We found that ART inhibited the proliferation of EC cells and enhanced the radiosensitivity of TE-1 cells (SER = 1...

The Ets-1 transcription factor plays an important role in various physiological and pathological processes. These diverse roles of Ets-1 are likely to depend on its interaction proteins. We have previously showed that Ets-1 interacted with DNA-dependent protein kinase (DNA-PK) complex including its regulatory subunits, Ku70 and Ku86 and with poly (ADP-ribose) polymerase-1 (PARP-1). In this study, the binding domains for the interaction between Ets-1 and these proteins were reported. We demonstrated that the interaction of Ets-1 with DNA-PK was mediated through the Ku70 subunit and was mapped to the C-terminal region of Ets-1 and the C-terminal part of Ku70 including SAP domain...

Radiation therapy is one of the most important treatments for unresectable and locally advanced esophageal squamous cell carcinoma (ESCC), however, the response to radiotherapy is sometimes limited by the development of radioresistance. Sinomenine hydrochloride (SH) has anticancer activity, but its effect on the radiosensitivity of ESCC is unclear. We determined the effect of SH on the radiosensitivity of ESCC cells and elucidated its potential radiosensitization mechanisms in vitro and in vivo. ESCC cells were subjected to SH and radiation, both separately and in combination...

DNA double-strand breaks (DSBs) are recognized and repaired by the Classical Non-Homologous End-Joining (C-NHEJ) and Homologous Recombination pathways. C-NHEJ includes the core Ku70 and Ku80 (or Ku86) heterodimer that binds DSBs and thus promotes recruitment of accessory downstream NHEJ factors XLF, PAXX, DNA-PKcs, Artemis and other core subunits, XRCC4 and DNA Ligase 4 (Lig4). In the absence of core C-NHEJ factors, DNA repair can be performed by Alternative End-Joining, which likely depends on DNA Ligase 1 and DNA Ligase 3...

Suberoyl anilide hydroxamic acid (SAHA) is one of the most promising Histone deacetylases(HDAC) inhibitors which has shown significant anti-tumor activity for many malignancies. We explored the potential mechanism of the radiosensitivity effect of SAHA in Panc-1 cells and attempted to develop SAHA as a systemic treatment strategy for pancreatic cancer. Growth inhibition was detected by CCK-8 assay. Radiosensitizing enhancement ratio was determined by clonogenic assay. The cell cycle and apoptosis assay was detected using flow cytometry and annexin-V/PI...

Antibody class-switch DNA recombination (CSR) is initiated by AID-introduced DSBs in the switch (S) regions targeted for recombination, as effected by Ku70/Ku86-mediated NHEJ. Ku-deficient B cells, however, undergo (reduced) CSR through an alternative(A)-NHEJ pathway, which introduces microhomologies in S-S junctions. As microhomology-mediated end-joining requires annealing of single-strand DNA ends, we addressed the contribution of single-strand annealing factors HR Rad52 and translesion DNA polymerase θ to CSR...

OBJECTIVE: The management of locally advanced cervical cancer has improved significantly with the advent of cisplatin-based chemoradiotherapy (CRT) as the primary treatment regimen. Nevertheless, a significant proportion of patients fail to respond or relapse on this treatment and have a very poor prognosis. Our goal was to determine the prognostic value of a panel of proteins involved in detection and repair of DNA damage. METHODS: We performed fluorescence immunohistochemistry, and used software analysis to assess expression of DNA damage response proteins ATM, DNA-PKcs, PARP-1, Ku70 and Ku86 in 117 pre-treatment specimens from patients with locally advanced cervical cancer...

Werner syndrome (WS) is characterized by the premature onset of several age-associated pathologies including cancer. The protein defective in WS patients (WRN) is a helicase/exonuclease involved in DNA replication and repair. Here, we present the results of a large-scale proteome analysis that has been undertaken to determine protein partners of different polymorphic WRN proteins found with relatively high prevalence in the human population. We expressed different fluorescently tagged-WRN (eYFP-WRN) variants in human 293 embryonic kidney cells (HEK293) and used a combination of affinity-purification and mass spectrometry to identify different compositions of WRN-associated protein complexes...

Binge drinking is known to cause damage in critical areas of the brain, including the hippocampus, which is important for relational memory and is reported to be sensitive to alcohol toxicity. However, the roles of DNA double-strand break (DSB) and its repair pathways, homologous recombination (HR), and non-homologous end joining (NHEJ) in alcohol-induced hippocampal injury remain to be elucidated. The purpose of this first study was to assess alcohol-induced DNA DSB and the mechanism by which alcohol affects DSB repair pathways in rat hippocampus...