Dataset Information

RAD9 enhances radioresistance of human prostate cancer cells through regulation of ITGB1 protein levels.

ABSTRACT: Mouse embryonic stem cells null for Rad9 are sensitive to deleterious effects of ionizing radiation exposure. Likewise, integrin ?1 is a known radioprotective factor. Previously, we showed that RAD9 downregulation in human prostate cancer cells reduces integrin ?1 protein levels and ectopic expression of Mrad9 restores inherent high levels.We used RNA interference to knockdown Rad9 expression in PC3 and DU145 prostate cancer cells. These cells were then exposed to ionizing radiation, and integrin ?1 protein levels were measured by immunoblotting. Survival of irradiated cells was measured by clonogenicity, cell cycle analysis, PARP-1 cleavage, and trypan blue exclusion.The function of RAD9 in controlling integrin ?1 expression is unique and not shared by the other members of the 9-1-1 complex, HUS1 and RAD1. RAD9 or integrin ?1 silencing sensitizes DU145 and PC3 cells to ionizing radiation. Irradiation of DU145 cells with low levels of RAD9 induces cleavage of PARP-1 protein. High levels of ionizing radiation have no effect on integrin ?1 protein levels. However, when RAD9 downregulation is combined with 10?Gy of ionizing radiation in DU145 or PC3 cells, there is an additional 50% downregulation of integrin ?1 compared with levels in unirradiated RAD9 knockdown cells. Finally, PC3 cells growing on fibronectin display increased radioresistance. However, PC3 cells with RAD9 knockdown are no longer protected by fibronectin after treatment with ionizing radiation.Downregulation of RAD9 when combined with ionizing radiation results in reduction of ITGB1 protein levels in prostate cancer cells, and increased lethality.

SUBMITTER: Broustas CG

PROVIDER: S-EPMC4142073 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

RAD9 enhances radioresistance of human prostate cancer cells through regulation of ITGB1 protein levels.

Broustas Constantinos G CG Lieberman Howard B HB

The Prostate 20140811 14

<h4>Background</h4>Mouse embryonic stem cells null for Rad9 are sensitive to deleterious effects of ionizing radiation exposure. Likewise, integrin β1 is a known radioprotective factor. Previously, we showed that RAD9 downregulation in human prostate cancer cells reduces integrin β1 protein levels and ectopic expression of Mrad9 restores inherent high levels.<h4>Methods</h4>We used RNA interference to knockdown Rad9 expression in PC3 and DU145 prostate cancer cells. These cells were then exposed ...[more]

PMID: 25111005

Similar Datasets

Project description:BackgroundRadiation therapy is one of the most common treatments for non-small cell lung cancer (NSCLC). However, the insensitivity of some tumor cells to radiation is one of the major reasons for the poor efficacy of radiotherapy and the poor prognosis of patients, and exploring the underlying mechanisms behind radioresistance is the key to solving this clinical challenge. This study aimed to identify the molecules associated with radioresistance in lung adenocarcinoma (LUAD), identified thyroid hormone receptor interactor 13 (TRIP13) as the main target initially, and explored whether TRIP13 is related to radioresistance in LUAD and the specific mechanism, with the aim of providing theoretical basis and potential targets for the combination therapy of LUAD patients receiving radiotherapy in the clinic.MethodsThree datasets, GSE18842, GSE19188 and GSE33532, were selected from the Gene Expression Omnibus (GEO) database and screened for differentially expressed genes (|log FC|>1.5, P<0.05) in each of the three datasets using the R 4.1.3 software, and then Venn diagram was used to find out the differentially expressed genes common to the three datasets. The screened differential genes were then subjected to protein-protein interaction (PPI) analysis and module analysis with the help of STRING online tool and Cytoscape software, and survival prognosis analysis was performed for each gene with the help of Kaplan-Meier Plotter database, and the TRIP13 gene was identified as the main molecule for subsequent studies. Subsequently, the human LUAD cell line H292 was irradiated with multiple X-rays using a sub-lethal dose irradiation method to construct a radioresistant cell line, H292DR. The radioresistance of H292DR cells was verified using cell counting kit-8 (CCK-8) assay and clone formation assay. The expression levels of TRIP13 in H292 and H292DR cells were measured by Western blot. Small interfering RNA (siRNA) was used to silence the expression of TRIP13 in H292DR cells and Western blot assay was performed. The clone formation ability and migration ability of H292DR cells were observed after TRIP13 silencing, followed by the detection of changes in the expression levels of proteins closely related to homologous recombination, such as ataxia telangiectasia mutated (ATM) protein.ResultsScreening of multiple GEO datasets, validation of external datasets and survival analysis revealed that TRIP13 was highly expressed in LUAD and was associated with poor prognosis in LUAD patients who had received radiation therapy. And the results of gene set enrichment analysis (GSEA) of TRIP13 suggested that TRIP13 might be closely associated with LUAD radioresistance by promoting homologous recombination repair after radiation therapy. Experimentally, TRIP13 expression was found to be upregulated in H292DR, and silencing of TRIP13 was able to increase the sensitivity of H292DR cells to radiation.ConclusionsTRIP13 is associated with poor prognosis in LUAD patients treated with radiation, possibly by promoting a homologous recombination repair pathway to mediate resistance of LUAD cells to radiation.

Dataset Information

RAD9 enhances radioresistance of human prostate cancer cells through regulation of ITGB1 protein levels.

Publications

RAD9 enhances radioresistance of human prostate cancer cells through regulation of ITGB1 protein levels.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets