THZ531 Induces a State of BRCAness in Multiple Myeloma Cells: Synthetic Lethality with Combination Treatment of THZ 531 with DNA Repair Inhibitors.

Journal Article (Journal Article)

Multiple myeloma (MM) is a hematological disease marked by abnormal growth of B cells in bone marrow. Inherent chromosomal instability and DNA damage are major hallmarks of MM, which implicates an aberrant DNA repair mechanism. Studies have implicated a role for CDK12 in the control of expression of DNA damage response genes. In this study, we examined the effect of a small molecule inhibitor of CDK12-THZ531 on MM cells. Treatment of MM cells with THZ531 led to heightened cell death accompanied by an extensive effect on gene expression changes. In particular, we observed downregulation of genes involved in DNA repair pathways. With this insight, we extended our study to identify synthetic lethal mechanisms that could be exploited for the treatment of MM cells. Combination of THZ531 with either DNA-PK inhibitor (KU-0060648) or PARP inhibitor (Olaparib) led to synergistic cell death. In addition, combination treatment of THZ531 with Olaparib significantly reduced tumor burden in animal models. Our findings suggest that using a CDK12 inhibitor in combination with other DNA repair inhibitors may establish an effective therapeutic regimen to benefit myeloma patients.

Full Text

Duke Authors

Cited Authors

  • Shyamsunder, P; Sridharan, SP; Madan, V; Dakle, P; Zeya, C; Kanojia, D; Chng, W-J; Ong, ST; Koeffler, HP

Published Date

  • January 21, 2022

Published In

Volume / Issue

  • 23 / 3

PubMed ID

  • 35163134

Pubmed Central ID

  • PMC8835885

Electronic International Standard Serial Number (EISSN)

  • 1422-0067

Digital Object Identifier (DOI)

  • 10.3390/ijms23031207


  • eng

Conference Location

  • Switzerland