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Biology subjects

McDermott-Roe, C.

Publications and source records attributed to McDermott-Roe, C..

2 recordsLinked to original sources

Aurora kinase A is a synthetic lethal target in FANCA-deficient cancers

Loss-of-function genomic alterations in FANCA occur across multiple cancer types, yet no molecularly tailored therapies have successfully exploited this potential vulnerability. Using complementary unbiased approaches, including a genome-wide CRISPR/Cas9 loss-of-function screen and a high-throughput drug screen in isogenic cancer cell-based models, we identified Aurora kinase A (AURKA) as a reproducible synthetic lethal target of FANCA-deficient cancers. Inhibition of AURKA induced chromosomal instability, micronucleation, and early G2/M arrest selectively in FANCA-deficient cells, consistent with an increased reliance on mitotic checkpoint control. Mechanistically, FANCA deficiency is associated with an elevated AURKA expression at both the transcriptomic and protein levels, and with an upregulation of mitotic spindle and G2/M checkpoint gene signatures. Analysis of large-scale cancer genomics datasets, including over 650,000 clinically sequenced tumors, confirms that FANCA is the most frequently altered Fanconi anemia pathway gene across cancers, and that Fanconi anemia-defective tumors exhibit an increased tumor mutational burden and genomic instability. Collectively, our findings point to AURKA inhibition as a promising precision treatment strategy in FANCA-deficient cancers and provide a rationale to further explore this strategy in the clinic.

cancer biology↗

CRISPR/Cas9 screens implicate RARA and SPNS1 in doxorubicin cardiotoxicity

Doxorubicin (DOX) is an efficacious chemotherapy compound used to treat various cancers which elicits severe side effects, including heart failure. Uptake of DOX by cardiomyocytes causes metabolic dysfunction and cell death but causal mechanisms remain largely undefined. We applied genome-wide CRISPR/Cas9 knockout screens to discover genetic modifiers of DOX-induced cardiomyocyte cell death, and independently, DOX uptake and clearance. Both screens discovered known and novel factors. In cell death screens and validation studies, loss of retinoic acid receptor- (RARA) predisposed cardiomyocytes to DOX-mediated cell death. Conversely, RARA activation reduced DOX cytotoxicity in wild type cardiomyocytes. RNA-Seq analysis revealed that whilst DOX caused large-scale suppression of metabolic and mitochondrial gene expression, RARA activation mitigated this effect. In DOX accumulation screens, an essential role for lysosomes in DOX clearance was observed. Loss of Sphingolipid Transporter 1 (SPNS1) led to DOX hyperaccumulation, suppression of autophagy, increased DNA damage, and increased cell death. Hence, SPNS1 plays a key role in buffering against DOX accumulation and toxicity. Collectively, our study nominated hundreds of drug-gene interactions, providing a springboard for exploration of causal mechanisms, and a technical framework for future screening campaigns.

cell biology↗