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Updated: Jan 10, 2026
Preparation of Mitochondria from Ovarian Cancer Tissues and Control Ovarian Tissues for Quantitative Proteomics Analysis
Published on: November 18, 2019
Surveying the Proteome-Wide Landscape of Mitoxantrone and Examining Drug Sensitivity in BRCA1-Deficient Ovarian
Savanna Wallin1, Sneha Pandithar1, Sarbjit Singh1
1Eppley Institute for Research in Cancer and Allied Diseases, Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, NE 68198, USA.
Abstract:
Background: Mitoxantrone (MX) is regularly used to treat several cancers. Despite its long history in the clinic, recent studies continue to unveil novel protein targets. These targets may contribute to the cytotoxic effects of the drug, as well as potential non-canonical antitumor activity. A better understanding of MX's cellular targets is required to fully comprehend the molecular consequences of treatment and to interpret MX sensitivity in homologous recombination (HR)-deficient cancer. Methods: Here, we evaluated MX activity in HR-deficient UWB1.289 (BRCA1-) ovarian cancer cells and surveyed the binding profile of MX using TMT-labeled quantitative proteomics and chemoproteomics. Results: Mass spectrometry (MS) analysis of cellular extracts from MX-treated BRCA1-UWB1.289 cells revealed unique downregulation of pathways instrumental in maintaining genomic stability, including single-strand annealing. Moreover, the BRCA1- cells exhibited a significant upregulation of proteins involved in ribosome biogenesis and RNA processing. Additional MS analyses following affinity-purification using a biotinylated-mitoxantrone probe corroborated these findings, which showed considerable targeting of proteins involved in genome maintenance and RNA processing. Conclusions: Our results suggest that an interplay of both canonical and non-canonical MX-antitumor activity overwhelms the BRCA1- UWB1.289 cells. Furthermore, this study characterizes the target landscape of MX, providing insights into off-target effects and MX action in HR-deficient cancer.
Insights
Mitoxantrone (MX) targets proteins involved in DNA repair and RNA processing in BRCA1-deficient ovarian cancer cells. This reveals new insights into its anti-cancer mechanisms and potential side effects.
Area of Science:
- Oncology
- Molecular Biology
- Proteomics
Background:
- Mitoxantrone (MX) is a chemotherapy drug with established use in cancer treatment.
- Recent research suggests MX has novel protein targets beyond its known mechanisms.
- Understanding these targets is crucial for interpreting MX efficacy in homologous recombination (HR)-deficient cancers.
Purpose of the Study:
- To investigate the activity and binding profile of Mitoxantrone (MX) in HR-deficient ovarian cancer cells.
- To identify novel protein targets of MX using quantitative proteomics and chemoproteomics.
Main Methods:
- Utilized TMT-labeled quantitative proteomics to analyze protein expression in MX-treated BRCA1-deficient UWB1.289 ovarian cancer cells.
- Employed chemoproteomics with a biotinylated-MX probe and mass spectrometry to identify MX binding proteins.
- Evaluated MX activity specifically in homologous recombination (HR)-deficient cancer models.
Main Results:
- MX treatment led to downregulation of genomic stability pathways, including single-strand annealing, in BRCA1-deficient cells.
- Observed significant upregulation of proteins involved in ribosome biogenesis and RNA processing in these cells.
- Proteomics and chemoproteomics confirmed MX targets proteins crucial for genome maintenance and RNA processing.
Conclusions:
- Mitoxantrone exhibits both canonical and non-canonical antitumor activities that impact HR-deficient cancer cells.
- The study elucidates the target landscape of MX, offering insights into its off-target effects.
- Findings provide a deeper understanding of MX's action in HR-deficient cancers, particularly ovarian cancer.
