Dataset Information

MMSET/WHSC1 enhances DNA damage repair leading to an increase in resistance to chemotherapeutic agents.

ABSTRACT: MMSET/WHSC1 is a histone methyltransferase (HMT) overexpressed in t(4;14)+ multiple myeloma (MM) patients, believed to be the driving factor in the pathogenesis of this MM subtype. MMSET overexpression in MM leads to an increase in histone 3 lysine 36 dimethylation (H3K36me2), and a decrease in histone 3 lysine 27 trimethylation (H3K27me3), as well as changes in proliferation, gene expression and chromatin accessibility. Prior work linked methylation of histones to the ability of cells to undergo DNA damage repair. In addition, t(4;14)+ patients frequently relapse after regimens that include DNA damage-inducing agents, suggesting that MMSET may play a role in DNA damage repair and response. In U2OS cells, we found that MMSET is required for efficient non-homologous end joining as well as homologous recombination. Loss of MMSET led to loss of expression of several DNA repair proteins, as well as decreased recruitment of DNA repair proteins to sites of DNA double-strand breaks (DSBs). By using genetically matched MM cell lines that had either high (pathological) or low (physiological) expression of MMSET, we found that MMSET-high cells had increased damage at baseline. Upon addition of a DNA-damaging agent, MMSET-high cells repaired DNA damage at an enhanced rate and continued to proliferate, whereas MMSET-low cells accumulated DNA damage and entered cell cycle arrest. In a murine xenograft model using t(4;14)+ KMS11 MM cells harboring an inducible MMSET shRNA, depletion of MMSET enhanced the efficacy of chemotherapy, inhibiting tumor growth and extending survival. These findings help explain the poorer prognosis of t(4;14) MM and further validate MMSET as a potential therapeutic target in MM and other cancers.

SUBMITTER: Shah MY

PROVIDER: S-EPMC6071667 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

MMSET/WHSC1 enhances DNA damage repair leading to an increase in resistance to chemotherapeutic agents.

Shah M Y MY Martinez-Garcia E E Phillip J M JM Chambliss A B AB Popovic R R Ezponda T T Small E C EC Will C C Phillip M P MP Neri P P Bahlis N J NJ Wirtz D D Licht J D JD

Oncogene 20160425 45

MMSET/WHSC1 is a histone methyltransferase (HMT) overexpressed in t(4;14)+ multiple myeloma (MM) patients, believed to be the driving factor in the pathogenesis of this MM subtype. MMSET overexpression in MM leads to an increase in histone 3 lysine 36 dimethylation (H3K36me2), and a decrease in histone 3 lysine 27 trimethylation (H3K27me3), as well as changes in proliferation, gene expression and chromatin accessibility. Prior work linked methylation of histones to the ability of cells to underg ...[more]

PMID: 27109101

Similar Datasets

Project description:BackgroundHyperthermic intraperitoneal chemotherapy (HIPEC) has been shown to be clinically effective, but the mechanisms by which hyperthermia enhances the sensitivity of cells to chemotherapeutic drugs has not yet been elucidated.MethodsTo identify the key molecules involved in thermochemotherapy, this study used mass spectrometry (MS)-based quantitative proteomics technology to analyze the effects of thermochemotherapy on the heat-sensitive ovarian cancer cell line A2780. We divided the A2780 cell line into four groups, one group served as blank control, and the other three groups were stimulated by oxaliplatin, stimulated by hyperthermia at 42 ℃, and stimulated by hyperthermia combined with oxaliplatin. Samples were then collected for tandem mass tag (TMT) labeling, high-performance liquid chromatography fractionation, and MS-based quantitative proteomics for analysis The differentially expressed proteins were quantitatively compared and identified, and Gene Ontology (GO) assessment and cluster analyses were performed. Finally, the above MS results were verified again by Western blotting experiments.ResultsA total of 349 differentially expressed proteins were identified between cells treated with chemotherapy alone (group B) and cells treated with a combination of chemotherapy and hyperthermia (group D). There were 145 upregulated proteins and 204 downregulated proteins. Among the top 20 proteins with significantly different expression levels, nearly two-thirds were involved in DNA damage repair. These proteins were subsequently verified by Western blot analysis. Indeed, consistent with MS data, the expression of the RBL1 protein was significantly upregulated in cells treated with thermochemotherapy (group D) compared to cells treated with chemotherapy alone (group B).ConclusionsIn heat-sensitive ovarian cancer cells, the damage repair of tumor cell DNA is disturbed by hyperthermia, making it unable to fully repair when damaged by chemotherapeutic drugs. As a result, hyperthermia enhances the efficacy of chemotherapeutic drugs. RBL1, as a tumor suppressor gene, may be associated with the repair of DNA damage, and thus it may be a key target for hyperthermia to enhance the sensitivity of thermosensitive cells to chemotherapeutic drugs.

Dataset Information

MMSET/WHSC1 enhances DNA damage repair leading to an increase in resistance to chemotherapeutic agents.

Publications

MMSET/WHSC1 enhances DNA damage repair leading to an increase in resistance to chemotherapeutic agents.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets