Integrated multi-omics analysis of RB-loss identifies widespread cellular programming and synthetic weaknesses

Area of Science:

• Cell Biology
• Molecular Oncology
• Cancer Research

Background:

• Retinoblastoma (RB) protein inactivation is a key event in cancer development.
• The precise molecular consequences of RB loss in human cells remain incompletely understood.

Purpose of the Study:

• To comprehensively analyze the cellular reprogramming induced by RB depletion in non-tumorigenic human cells.
• To identify molecular pathways and metabolic changes essential for the proliferation of RB-deficient cancer cells.

Main Methods:

• Quantitative measurement of transcriptional, proteomic, and metabolic profiles following RB depletion in RPE1 cells.
• Comparison of cellular alterations with data from Retinoblastoma and Small Cell Lung Cancer patient tumors.
• In vivo validation using RB1-/- cells and Drosophila E2f1-RNAi models to assess the impact of pathway inhibition on cell growth.

Main Results:

• RB depletion causes widespread transcriptional, proteomic, and metabolic reprogramming, including changes in E2F-regulated factors and cell stress responses.
• Identified non-E2F-regulated pathways that are sensitive to RB loss, potentially supporting RB-depleted cell growth.
• Observed conservation of these molecular alterations in human RB1-/- tumors, validating the RPE1 cell model.

Conclusions:

• RB loss induces significant cellular reprogramming with conserved alterations in human cancers.
• Key metabolic pathways are essential for the survival and growth of RB-deleted human cells.
• These findings highlight critical metabolic vulnerabilities in RB-deficient cancers that could be therapeutically exploited.