Transcriptome analyses reveal epigenetic and radiation related genes in NSCLC cell
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ABSTRACT: Purpose: Radiotherapy is useful for non-small cell lung cancer (NSCLC) patients who cannot be treated surgically. Modification of histone proteins occurs during radiotherapy, and affects gene expression.In this study, we assessed the effects of radiotherapy on histone modification via 3-deazaneplanocin A (DZNep) in NSCLC cells. Methods: NCI-H460 NSCLC cell line were subjected to gamma irradiation. To reveal histone modification reagent DZNep targeted genes, we conducted mRNA-sequencing. Results: We evaluated the epigenetic regulation of autophagy-related genes by DZNep through mRNA-sequencing, and we identified genes that are differentially expressed upon irradiation, including a candidate histone modification target gene.
Project description:Purpose: Radiotherapy is useful for non-small cell lung cancer (NSCLC) patients who cannot be treated surgically. Modification of histone proteins also occurs during radiotherapy, and affects gene expression. In this study, we assessed the effects of radiotherapy on histone H4K20me3 in NSCLC cells. Methods: NCI-H460 NSCLC cell line were subjected to gamma irradiation. To reveal H4K20me3-related genes, we conducted chromatin immunoprecipitation(ChIP) and ChIP-sequencing. Results: We evaluated the H4K20me3-related genes through ChIP-sequencing.
Project description:Radiotherapy is an important treatment for non-small cell lung cancer (NSCLC). It not only kills tumor cells directly, but also promotes the efficacy of immunotherapy. However, resistance to radiotherapy is still an unavoidable clinical challenge. In this study, we used radiation-sensitive H460 cell line to stably express Cas9 and CRISPR GeCKO v2 library (A and B). Then a single 4GY irradiation was given, and after the cells resumed proliferation, the total genome was extracted and second-generation sequencing was performed. Genes directly associated with resistance to radiotherapy were identified in comparison to controls without any treatment.
Project description:We demonstrated that 3-Deazaneplanocin A (DZNep), a histone methyltransferase inhibitor, induce robust apoptosis in AML cells through increased ROS production and ER stress. We identified a core gene signature including TXNIP, a major redox control molecule which is crucial in DZNep-induced apoptosis.
Project description:We demonstrated that 3-Deazaneplanocin A (DZNep), a histone methyltransferase inhibitor, induce robust apoptosis in AML cells through increased ROS production and ER stress. We identified a core gene signature including TXNIP, a major redox control molecule which is crucial in DZNep-induced apoptosis. MOLM-14 cells were treated with DMSO and DZNep 2 µM for 24 hours
Project description:We explored H3K27me3 binding sites in the genome of differentiated, conditionally immortalized mouse podocytes. Cells were allowed to differentiate for 14 days, following thermoshifting, before treatment with either vehicle (DMSO) or the S-adenosylhomocysteine hydrolase inhibitor 3-deazaneplanocin A (DZNep, 5µM for 48 hours) which degrades the histone methyltransferase, EZH2 ordinarily responsible for H3K27 trimethylation (H3K27me3). DNA was immunopreciptated with an H3K27me3-specific antibody. Studying H3K27me3 modification in Mouse Podocyte
Project description:3-deazaneplanocin A (DZNeP) is a promising cancer drug affecting the methylation status of histone lysine residues. To investigate the specificity and mode of action of DZNeP, zebrafish embryos displaying high histone methyltransferase activity were cultured with DZNeP and histone methylation (H3K4me3, H3K9me3, H3K27me3) was mapped by ChIP-chip genome-wide promoter at post-MBT stage (5.3 hpf) . We used a custom 2.1M probe HD promoter array (Nimblegen) for ChIP and input DNA hybridization. Peak detection was done using MA2C with P=10e-4 as cutoff.
Project description:DNA methylation, histone modifications, and nucleosomal occupancy collaborate to cause silencing of tumor related genes in cancer. The development of drugs that target these processes is therefore important for cancer therapy. Inhibitors of DNA methylation and histone deacetylation have already been approved by the FDA for the treatment of hematologic malignancies. However, drugs that target the other mechanisms still need to be developed. Recently, 3-deazaneplanocin A (DZNep) was reported to selectively inhibit the trimethylation of lysine 27 on histone H3 (H3K27me3) and lysine 20 on histone H4 (H4K20me3) as well as re-activate silenced genes in cancer cells. This finding opens the door to pharmacological inhibition of histone methylation and we therefore wanted to further study the mechanism of action of 3-deazaneplanocin A in cancer cells. Western blot analysis showed that two other drugs, sinefungin and adenosine-dialdehyde (Adox), have similar effects on the trimethylation H3K27 as 3-deazaneplanocin A and that DZNep is not selective, but globally inhibits histone methylation. Intriguingly, chromatin immunoprecipitation of various histone modifications and microarray analysis show DZNep acts via a different pathway to 5-aza-2´-deoxycytidine (5-azaCdR), a DNA methyltransferase inhibitor and gives us an interesting insight into how chromatin structure effects gene expression. We also determine the kinetics of gene activation in order to understand if the induced changes were somatically heritable. We have found that upon removal of DZNep, gene expression is reduced to its original state suggesting that there is a homeostatic mechanism which returns the histone modifications to their “ground state” after DZNep treatment. Not only do these studies show the strong need for further development of histone methylation inhibitors but also allow us to better understand how chromatin structure affects gene expression.
Project description:DNA methylation, histone modifications, and nucleosomal occupancy collaborate to cause silencing of tumor related genes in cancer. The development of drugs that target these processes is therefore important for cancer therapy. Inhibitors of DNA methylation and histone deacetylation have already been approved by the FDA for the treatment of hematologic malignancies. However, drugs that target the other mechanisms still need to be developed. Recently, 3-deazaneplanocin A (DZNep) was reported to selectively inhibit the trimethylation of lysine 27 on histone H3 (H3K27me3) and lysine 20 on histone H4 (H4K20me3) as well as re-activate silenced genes in cancer cells. This finding opens the door to pharmacological inhibition of histone methylation and we therefore wanted to further study the mechanism of action of 3-deazaneplanocin A in cancer cells. Western blot analysis showed that two other drugs, sinefungin and adenosine-dialdehyde (Adox), have similar effects on the trimethylation H3K27 as 3-deazaneplanocin A and that DZNep is not selective, but globally inhibits histone methylation. Intriguingly, chromatin immunoprecipitation of various histone modifications and microarray analysis show DZNep acts via a different pathway to 5-aza-2´-deoxycytidine (5-azaCdR), a DNA methyltransferase inhibitor and gives us an interesting insight into how chromatin structure effects gene expression. We also determine the kinetics of gene activation in order to understand if the induced changes were somatically heritable. We have found that upon removal of DZNep, gene expression is reduced to its original state suggesting that there is a homeostatic mechanism which returns the histone modifications to their “ground state” after DZNep treatment. Not only do these studies show the strong need for further development of histone methylation inhibitors but also allow us to better understand how chromatin structure affects gene expression.
Project description:The epigenetic treatment by 3-Deazaneplanocin A (DZNep), a histone methyltransferase inhibitor, shows great potential against acute myeloid leukemia (AML). However, the variant sensitivity and incomplete response to DZNep are commonly observed. We reveal that vitamin C (Vc) dramatically promotes DZNep response against leukemic cells in different cell lines and primary AML samples. To examine the molecular determinants underlying Vc enhanced anti-leukemia effect of DZNep, we conducted a genome-wide RNA sequencing and a gene ontology (GO) enrichment analysis of differentially expressed mRNAs in each group was performed.
Project description:3-deazaneplanocin A (DZNeP) is a promising cancer drug affecting the methylation status of histone lysine residues. To investigate the specificity and mode of action of DZNeP, zebrafish embryos displaying high histone methyltransferase activity were cultured with DZNeP and histone methylation (H3K4me3, H3K9me3, H3K27me3) was mapped by ChIP-chip genome-wide promoter at post-MBT stage (5.3 hpf) . We used a custom 2.1M probe HD promoter array (Nimblegen) for ChIP and input DNA hybridization. Peak detection was done using MA2C with P=10e-4 as cutoff. ChIP-chip experiments were performed from chromatin prepared by sonication after formaldehyde cross-linking, from embryos are the indicated developmental stages and ChIP DNA was hybridized onto the aforementioned Nimbegen promoter arrays.