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Epigenetic dysregulation has been strongly implicated in carcinogenesis and is one of the mechanisms that contribute to the development of lung cancer. Using genome-wide CRISPR/Cas9 library screening, we showed SET domain-containing protein 1A (SETD1A) is an essential epigenetic modifier of the proliferation of NSCLC H1299 cells. Depletion of SETD1A strikingly inhibited the proliferation of NSCLC cells. IHC staining and bioinformatics showed that SETD1A is upregulated in lung cancer. Kaplan-Meier survival analysis indicated that high expression of SETD1A is associated with poor prognosis of patients with NSCLC. We revealed that loss of SETD1A inhibits DNA replication and induces replication stress accompanied by impaired fork progression. In addition, transcription of CDC7 and TOP1, which are involved in replication origin activation and fork progression, respectively, was significantly reduced by knockdown of SETD1A. Taken together, these findings demonstrated SETD1A is a critical epigenetic modifier of NSCLC cell proliferation by promoting the transcription of a subset of DNA replication-associated genes. • SETD1A is an essential epigenetic modifier for proliferation of H1299 cells. • SETD1A knockdown impairs replication fork progression and induces replication stress. • SETD1A is required to transcription of S-phase associated target gene s via H3K4me3 methylation. [ABSTRACT FROM AUTHOR]

Objectives: The level of histone H3 lysine 79 methylation is regulated by the cell cycle and involved in cell proliferation. KDM2B is an H3K79 demethylase. Proliferating cell nuclear antigen (PCNA) is a component of the DNA replication machinery. This study aimed at elucidating a molecular link between H3K79me recognition of PCNA and cell cycle control. Materials and methods: We generated KDM2B‐depleted 293T cells and histone H3‐K79R mutant‐expressing 293T cells. Western blots were primarily utilized to examine the H3K79me level and its effect on subsequent PCNA dissociation from chromatin. We applied IP, peptide pull‐down, isothermal titration calorimetry (ITC) and ChIP experiments to show the PCNA binding towards methylated H3K79 and DNA replication origins. Flow cytometry, MTT, iPOND and DNA fibre assays were used to assess the necessity of KDM2B for DNA replication and cell proliferation. Results: We revealed that KDM2B‐mediated H3K79 demethylation regulated cell cycle progression. We found that PCNA bound chromatin in an H3K79me‐dependent manner during S phase. KDM2B was responsible for the timely dissociation of PCNA from chromatin, allowing to efficient DNA replication. Depletion of KDM2B aberrantly enriched chromatin with PCNA and caused slow dissociation of residual PCNA, leading to a negative effect on cell proliferation. Conclusions: We suggested a novel interaction between PCNA and H3K79me. Thus, our findings provide a new mechanism of KDM2B in regulation of DNA replication and cell proliferation. [ABSTRACT FROM AUTHOR]

Recently, the flash storage device becomes more important to the mobile consumer electronics that supports various functionalities because of its portability and reliability. The capacity of the flash storage device is becoming larger and its price is going down due to the mass production of the Triple-Level Cell (TLC) flash memory. Since TLC flash memories are very cheap, they are widely deployed in the mobile flash storage device although its durability is poor. In addition, it is difficult to handle the large-scale flash memories with limited memory resources in the mobile flash storage device. Therefore, TLC-based flash storage device requires to internally optimize the write and erase operations with small memory resources. This paper proposes a new hash-based mapping algorithm, which reduces the redundant write and erase operations and uses only a few memory resources, for the mobile flash storage device. The proposed hash algorithm also guarantees uniform performance regardless of various workload patterns. Through various experiments with related works, this paper shows the superiority of the proposed hash algorithm. [ABSTRACT FROM PUBLISHER]

The human myelogenous leukemic cell line, K562 undergoes erythroid differentiation by exposure to hemin. Here, we uncovered NSD2 as an innate erythroid differentiation-related factor through a genome-wide CRISPR library screen and explored the regulatory role of NSD2 during myeloid leukemia cell differentiation. We found that NSD2 stability was disrupted by poly-ubiquitination in differentiated K562 cells. Proteomic analysis revealed an interaction between NSD2 and an E3 ubiquitin ligase, BRCA1, which ubiquitylates NSD on K292. Depletion of BRCA1 stabilized NSD2 protein and suppressed K562 cell differentiation. Furthermore, BRCA1 protein level was decreased in bone marrow tumor, while NSD2 level was elevated. Surprisingly, among BRCA1 mutation(s) discovered in lymphoma patients, BRCA1 K1183R prevented its translocation into the nucleus, failed to reduce NSD2 protein levels in hemin-treated K562 cells and eventually disrupted cell differentiation. Our results indicate the regulation of NSD2 stability by BRCA1-mediated ubiquitination as a potential therapeutic target process in multiple myeloma. Park et al. identify Multiple Myeloma SET domain (MMSET/NSD2) in a large-scale CRISPR screen of genes whose depletion regulates hematopoietic differentiation and found it to interact with BRCA1. Thus regulation of MMSET/NSD2 stability BRCA1-mediated ubiquitination could be explored for potential therapeutic interventions in multiple myeloma. [ABSTRACT FROM AUTHOR]

Post‐translational modification of forkhead family transcription factor, FoxO1, is an important regulatory mode for its diverse activities. FoxO1 is acetylated by HAT coactivators and its transcriptional activity is decreased via reduced DNA binding affinity. Here, we report that SET/TAF‐Iβ inhibited p300‐mediated FoxO1 acetylation in an INHAT domain‐dependent manner. SET/TAF‐Iβ interacted with FoxO1 and activated transcription of FoxO1 target gene, p21. Moreover, SET/TAF‐Iβ inhibited acetylation of FoxO1 and increased p21 transcription induced by oxidative stress. Our results suggest that SET/TAF‐Iβ inhibits FoxO1 acetylation and activates its transcriptional activity toward p21.SET/TAF‐Iβ inhibits FoxO1 acetylation. SET/TAF‐Iβ interacts with FoxO1 in INHAT domain dependent manner. Recruitment of FoxO1 on p21 promoter is increased by SET/TAF‐Iβ. SET/TAF‐Iβ induces p21 transcription and apoptosis under oxidative stress. [ABSTRACT FROM AUTHOR]

The oncogene protein DEK is an abundant and ubiquitous nuclear protein with implications in acute myelogenous leukemia, as translocation which results in the formation of a DEK-CAN fusion protein. In a previous study, we have identified that DEK negatively regulated peroxiredoxin 6 (Prdx 6) transcription synergistically with the p65 subunit of NF-κB. In this study, we further investigated DEK-mediated transcriptional regulation of Prdx 6 during leukemia cell differentiation. Using Chromatin Immunoprecipitation analysis and Prdx 6 reporter assays, we found that DEK operated as a negative regulator of Prdx 6 transcription during leukemia cell differentiation. DEK was highly expressed and recruited to Prdx 6 promoter along with p65 and repressed transcription after leukemia cell differentiation. [ABSTRACT FROM PUBLISHER]

Highlights: [•] G9a upregulates p21 expression independently of its HMTase activity. [•] Positive regulation of p21 by G9a is p53 independent. [•] G9a interacts with PCAF to activate p21 expression. [•] G9a and PCAF are recruited to p21 promoter upon etoposide treatment. [•] G9a inhibits cell survival via p21-mediated apoptosis upon cellular stress. [ABSTRACT FROM AUTHOR]