A proof-of-concept study for the pathogenetic role of enhancer hypomethylation of MYBPHL in multiple myeloma

Sci Rep. 2021 Mar 26;11(1):7009. doi: 10.1038/s41598-021-86473-y.

Abstract

Enhancer DNA methylation and expression of MYBPHL was studied in multiple myeloma (MM). By bisulfite genomic sequencing, among the three CpGs inside the MYBPHL enhancer, CpG1 was significantly hypomethylated in MM cell lines (6.7-50.0%) than normal plasma cells (37.5-75.0%) (P = 0.007), which was negatively correlated with qPCR-measured MYBPHL expression. In RPMI-8226 and WL-2 cells, bearing the highest CpG1 methylation, 5-azadC caused enhancer demethylation and expression of MYBPHL. In primary samples, higher CpG1 methylation was associated with lower MYBPHL expression. By luciferase assay, luciferase activity was enhanced by MYBPHL enhancer compared with empty vector control, but reduced by site-directed mutagenesis of each CpG. RNA-seq data of newly diagnosed MM patients showed that MYBPHL expression was associated with t(11;14). MOLP-8 cells carrying t(11;14) express the highest levels of MYBPHL, and its knockdown reduced cellular proliferation and increased cell death. Herein, as a proof-of-concept, our data demonstrated that the MYBPHL enhancer, particularly CpG1, was hypomethylated and associated with increased MYBPHL expression in MM, which was implicated in myelomagenesis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Line, Tumor
  • Cell Proliferation / genetics
  • CpG Islands / genetics
  • Cytoskeletal Proteins / genetics*
  • Cytoskeletal Proteins / metabolism*
  • DNA Methylation / genetics*
  • Enhancer Elements, Genetic / genetics
  • Gene Expression Regulation, Neoplastic / genetics*
  • Humans
  • Multiple Myeloma / genetics*
  • Multiple Myeloma / pathology
  • Promoter Regions, Genetic / genetics
  • Proof of Concept Study
  • RNA Interference
  • RNA, Small Interfering / genetics
  • Syndecan-1 / metabolism

Substances

  • Cytoskeletal Proteins
  • MYBPHL protein, human
  • RNA, Small Interfering
  • SDC1 protein, human
  • Syndecan-1