Proteomics and Phosphoproteomics of High-Grade Serous Ovarian Carcinoma Models Investigating Ferroptosis Induction and MTDH-SND1 Inhibition

Abstract

High-grade serous ovarian carcinoma (HGSOC) is the most common subtype of ovarian cancer, often discovered in advanced stages and linked to poor survival. Due to high mortality rates, there is a need for novel treatment strategies. A promising new strategy is induction of ferroptosis, which has recently been shown to synergistically induce cell death in HGSOCs in combination with MTDH-SND1 protein interaction inhibition. To capture treatment effects, powerful tools which can be used to observe differences in protein expression and activation level are LC-MS/MS based proteomics and phosphoproteomics.

The aim of this study was to explore the proteomic and phosphoproteomic effects of the ferroptosis inducer Erastin and the MTDH-SND1 protein interaction inhibitor drug C26A6, alone and in combination, by treating HGSOC cell lines. The study involved mice cell lines, BPPNM and PPNM, which allowed for investigation of treatment effects on BRCA1-deficient cells, whereas human cell lines, KURAMOCHI and PEO1, served as a dual human model for HGSOC.

Overall, 7,174 proteins and 8,227 phosphosites in mice cell lines, and 7,649 proteins and 8,113 phosphosites in human cell lines, were quantified. Among all cell lines, the C26A6 and Erastin combination induced the most pronounced dysregulation, suggesting a synergistic effect. Additionally, BRCA1-deficient cells exhibited greater sensitivity to the combination treatment than BRCA1-proficient cells.

Overall, these findings support the synergistic effect of ferroptosis induction and MTDH-SND1 protein interaction inhibition, revealing possible biomarkers for treatment efficacy. This enhances the interest for further research into this novel treatment strategy.

Popular Abstract

Investigating new treatment options for poor prognosis ovarian cancer by exploring protein expression

Ovarian cancer is the deadliest gynecological cancer affecting women. Although current treatments include surgery to remove tumors followed by chemotherapy can be effective, many patients experience relapse and the mortality is high. This highlights an urgent need for new and more effective treatment strategies to improve survival and combat this devastating disease.

The most common and deadliest form of ovarian cancer is called high-grade serous ovarian carcinoma, accounting for about 63% of all ovarian cancer cases. Around 13% of patients with this subtype carry a mutation in breast cancer gene 1 or 2 (abbreviated BRCA1 or BRCA2), which increases their risk of developing aggressive cancers. This mutation can also affect how patients respond to treatments, making it an important focus in cancer research.

A new and promising cancer treatment approach focuses on triggering one of the cell’s natural self-destruct processes called ferroptosis, which is an iron-dependent form of regulated cell death. Certain drugs can induce this process to help kill cancer cells. This method is especially interesting for cancers with BRCA1-mutations, because those cells are more sensitive to ferroptosis and may respond better to this kind of treatment.

Recent findings have shown that ferroptosis induction, in combination with inhibition of a specific protein interaction connected to cancer progression, caused increased cancer cell death. The proteins involved in the interaction are called MTDH and SND1, and by blocking their interaction the tumor cells experienced an increased sensitivity to ferroptosis. This study set out to explore what happens inside cancer cells when these two strategies are combined.

The drugs used were Erastin, a ferroptosis inducer, and C26A6, a molecule which is known to interrupt the interaction between the two proteins mentioned above. The drugs were used as a single treatment of ovarian cancer cells, as well as in combination.

After growing high-grade serous ovarian carcinoma cells and treating them with the drugs, the proteins were extracted and analyzed using a method called LC-MS/MS. This analysis method also revealed which proteins were activated through a process called phosphorylation. Using computational analysis, protein expression across samples helped assess the effects of each treatment.

This study revealed an enhanced effect on protein expression of the two drugs in combination, compared to the single treatments. These findings implicate that it could be a useful new treatment option for patients with the subtype high-grade serous ovarian carcinoma. Furthermore, the study showed that cells with BRCA1-mutations experienced increased sensitivity to the combination treatment, indicating a specific usefulness of this treatment option for these patients. Further research is required to explore the therapeutic potential of these drugs more extensively, but they currently hold significant promise as a potential new cancer treatment for high-grade serous ovarian cancer.

• author: Bochis, Bianca and Persson, Elna
• supervisor: Fredrik Levander; Parisa Esmaeili
• organization: Department of Immunotechnology
• course: KIMM05 20251
• year: 2025
• type: H2 - Master's Degree (Two Years)
• subject: Technology and Engineering
• keywords: Ovarian cancer, High-grade serous ovarian carcinoma, Ferroptosis, Proteomics, Phosphoproteomics, Oncology
• language: English
• id: 9196338
• date added to LUP: 2025-06-11 12:45:25
• date last changed: 2025-06-11 12:45:25