Dissertation defence (Cell Biology and Anatomy): MSc Alejandra Verhassel
MSc Alejandra Verhassel defends the dissertation in Cell Biology and Anatomy titled “Detection of breast cancer cells through glycan modifications and their role in cancer growth and metabolism: use of nanoparticles in cancer detection” at the University of Turku on 27 November 2026 at 12.00 (TYKS, building 11, SH-auditorium, Kiinamyllynkatu 4-8, Turku).
Opponent: Associate Professor Sandra J. Van Vliet (Amsterdam UMC, the Netherlands)
Custos: Professor Emerita Pirkko Härkönen (University of Turku)
Summary of the Doctoral Dissertation:
Protein glycosylation is the binding of chains of sugar molecules to proteins. These chains of sugar molecules are called glycans. When a cell becomes cancerous, these glycans are commonly altered. These changes have often been observed at early stages of cancer and are studied as potential biomarkers.
The first aim of this study was to develop a new method of detecting two cancer-related glycan patterns that are frequently observed in breast and prostate cancer. For this purpose, newly synthesised fluorescently labelled nanoparticles were used. They were able to show specificity toward the glycan patterns of interest.
For the second aim, I studied the role of these cancer-related glycan patterns in breast cancer growth and metabolism. In this study, I focused on the Tn antigen, a glycan pattern that is present in more than 80 % of breast cancers. I observed decreased tumour growth and metabolic activities in cancer cells that were engineered to express high amounts of the Tn antigen. In addition, the experiments showed that under hypoxic conditions, the expression level of the Tn antigen was increased in non-engineered control cells. Hypoxia is a feature that is often seen in fast-growing tumours.
This study showed that the nanoparticles are specific toward the cancer-related glycan pattern of interest. In future, these particles could be used to detect breast and prostate cancer cells in biopsies and circulating tumour cell samples from patients with breast and prostate cancer. This could improve the detection of cancer at an early stage and the follow-up of cancer progression and treatment response. In addition, this study clarified the effects of increased Tn antigen expression on breast cancer cell growth and metabolism. The results also suggest hypoxia as one possible mechanism of increased Tn antigen expression in breast cancer.
