Uev1A counteracts oncogenic Ras stimuli in both polyploid and diploid cells

Area of Science:

• Cell Biology
• Genetics
• Cancer Research

Background:

• Oncogenic Ras proteins are known drivers of DNA replication stress, typically leading to senescence or cell death.
• Aberrant division stress in polyploid cells, particularly ovarian nurse cells, represents a less understood consequence of oncogenic Ras.
• Intrinsic protective mechanisms against Ras-induced aberrant division stress require further investigation.

Purpose of the Study:

• To identify protective mechanisms against oncogenic Ras-induced aberrant division stress in Drosophila ovarian nurse cells.
• To elucidate the role of the E2 enzyme Uev1A in cellular protection.
• To explore the therapeutic potential of Uev1A and its human homologs in cancer.

Main Methods:

• Genome-wide genetic screen in Drosophila to identify protective factors.
• Analysis of Uev1A's role in nurse cell death induced by oncogenic Ras.
• Investigation of Uev1A's interaction with the APC/C complex and its role in Cyclin A degradation.
• Assessment of Uev1A and human homologs (UBE2V1, UBE2V2) in diploid cell tumorigenesis models.

Main Results:

• Uev1A was identified as a key protector against oncogenic Ras-induced nurse cell death.
• Reduced Uev1A expression exacerbated cell death, while overexpression conferred protection.
• Uev1A collaborates with the APC/C complex to promote proteasomal degradation of Cyclin A.
• Uev1A and UBE2V1/2 suppressed oncogenic Ras-driven tumorigenesis in Drosophila and human colorectal xenografts.
• Elevated UBE2V1/2 expression correlated with improved survival in human colorectal cancer patients with KRAS mutations.

Conclusions:

• Uev1A plays a crucial role in mitigating aberrant division stress induced by oncogenic Ras.
• The Uev1A-APC/C-Cyclin A axis represents a novel protective pathway against Ras-driven cellular stress.
• Uev1A and its homologs hold promise as therapeutic targets for Ras-mutated cancers, particularly colorectal cancer.