Oncohistones: Hijacking the histone code.

Area of Science:

• Oncology
• Epigenetics
• Molecular Biology

Background:

• Chromatin dysfunction is increasingly linked to cancers, especially in pediatric and young adult populations.
• Mutations in histone genes, termed "oncohistones," are key drivers of tumorigenesis.
• Oncohistones like H3K27M and H3K36M disrupt histone methyltransferases, misregulating the epigenome and transcriptome.

Purpose of the Study:

• To review recent advancements in understanding the mechanisms of canonical and novel histone mutations in cancer.
• To explore the biochemical, molecular, and biological underpinnings of oncohistone function.
• To identify potential therapeutic targets for oncohistone-driven cancers.

Main Methods:

• Review of existing literature on histone mutations and cancer.
• Analysis of biochemical and molecular mechanisms of oncohistone function.
• Examination of the role of EZHIP in ependymomas.

Main Results:

• Hotspot missense mutations in histone H3 tails (H3K27M, H3K36M, H3.3G34R/W) inhibit histone methyltransferases and promote cancer.
• Widespread mutations in all four core histones are found across diverse cancer types.
• The protein EZHIP acts similarly to H3K27M mutations in driving childhood ependymomas.

Conclusions:

• Mechanistic insights into oncohistone mutations provide a foundation for targeted cancer therapies.
• Understanding these epigenetic alterations is crucial for developing effective treatments for oncohistone-driven malignancies.
• Further research into novel histone mutations and related proteins like EZHIP may uncover new therapeutic avenues.