Targeting DOT1L Epigenetic Moonlighting in MLL-Rearranged Leukemia

Area of Science:

• Hematological malignancies
• Oncology
• Drug discovery

Background:

• KMT2A-rearranged (MLL-r) leukemias are aggressive and require better targeted therapies.
• DOT1L is a key driver in these leukemias, but current inhibitors have modest clinical responses.
• DOT1L has catalytic and non-catalytic functions, necessitating broader inhibition strategies.

Purpose of the Study:

• To review the biology of DOT1L and its role in KMT2A-r leukemia.
• To discuss current small molecule therapies targeting MLL.
• To evaluate targeted degradation of DOT1L as a therapeutic strategy.

Main Methods:

• Review of existing literature on DOT1L biology and therapies.
• Analysis of proteolysis-targeting chimeras (PROTACs) for DOT1L degradation.
• Evaluation of preclinical data for DOT1L PROTACs.

Main Results:

• DOT1L PROTACs, like DOT1L808, show improved pharmacokinetics and preclinical efficacy.
• Targeted degradation offers a way to overcome limitations of catalytic DOT1L inhibitors.
• Challenges remain for clinical translation, including bioavailability and toxicity.

Conclusions:

• Targeted degradation of DOT1L via PROTACs is a promising strategy for KMT2A-r leukemia.
• Further research is needed to address clinical translation challenges.
• This approach may offer improved treatment outcomes for high-risk leukemias.