Group 3 medulloblastoma transcriptional networks collapse under domain specific EP300/CBP inhibition.
Noha A M ShendyMelissa BikowitzLogan H SiguaYang ZhangAudrey MercierYousef KhashanaStephanie NanceQi LiuIan M DelahuntySarah RobinsonVanshita GoelMatthew G ReesMelissa A RonanTingjian WangMustafa KocakJennifer A RothYingzhe WangBurgess B FreemanBrent A OrrBrian J AbrahamMartine F RousselErnst K SchonbrunnJun QiAdam D DurbinPublished in: Nature communications (2024)
Chemical discovery efforts commonly target individual protein domains. Many proteins, including the EP300/CBP histone acetyltransferases (HATs), contain several targetable domains. EP300/CBP are critical gene-regulatory targets in cancer, with existing high potency inhibitors of either the catalytic HAT domain or protein-binding bromodomain (BRD). A domain-specific inhibitory approach to multidomain-containing proteins may identify exceptional-responding tumor types, thereby expanding a therapeutic index. Here, we discover that targeting EP300/CBP using the domain-specific inhibitors, A485 (HAT) or CCS1477 (BRD) have different effects in select tumor types. Group 3 medulloblastoma (G3MB) cells are especially sensitive to BRD, compared with HAT inhibition. Structurally, these effects are mediated by the difluorophenyl group in the catalytic core of CCS1477. Mechanistically, bromodomain inhibition causes rapid disruption of genetic dependency networks that are required for G3MB growth. These studies provide a domain-specific structural foundation for drug discovery efforts targeting EP300/CBP and identify a selective role for the EP300/CBP bromodomain in maintaining genetic dependency networks in G3MB.
Keyphrases
- drug discovery
- genome wide
- small molecule
- gene expression
- dna methylation
- cancer therapy
- induced apoptosis
- binding protein
- squamous cell carcinoma
- high throughput
- quality improvement
- amino acid
- protein protein
- papillary thyroid
- oxidative stress
- endoplasmic reticulum stress
- heat shock
- quantum dots
- lymph node metastasis
- case control
- squamous cell