Luiz Zerbini, Cancer Genomics, Giuseppina Carbone and Carlo Catapano, Institute of Oncology Research (IOR) and Università della Svizzera Italiana (USI), have published their latest findings on experimental models and patients with aggressive prostate cancer in Communications Biology.
The scientific article, entitled “Circulating extracellular vesicles release oncogenic miR-424 in experimental models and patients with aggressive prostate cancer,” published in open access, outlines how the team investigated miR-424, a microRNA (miRNA) found in circulating small extracellular vesicles (exosomes). Exosomes, containing miRNA, mRNA and protein, can transfer signals across cells and facilitate propagation of oncogenic stimuli promoting disease evolution and metastatic spread of cancer. The team found that miR-424 containing exosomes are more frequently found in patients with metastatic prostate cancer than primary tumours or BPH. Normal prostate epithelial cells treated with miR-424 containing exosomes displayed stem-like traits and tumour initiating properties indicating that miR-424 can modify recipient cells. Tumour growth was promoted in xenograft models when miR-424 containing exosomes were intravenously injected to mice; this experiment mimics the effects of circulating exosomes in the patient blood.
This study provides a comprehensive analysis of the consequences of the release of circulating plasma exosomes in cancer patients, demonstrating the important role of this phenomenon in tumour progression and recurrence. These results may lead to novel approaches for diagnosing, monitoring and treatment of prostate cancer.
Dr. Giuseppina Carbone, senior author, explains the key findings of the study: “Exosomes are secreted by all kinds of cells and their purpose is to ensure communication between cells. The quantity and quality of the content of the exosomes released by the various sources is what makes the difference. In our study, we show that exosomes secreted by prostate cancer cells and containing this miRNA have the ability to intervene in other cells, making them less differentiated, more stem-like and thus more likely to form metastases. Since exosomes are found in every fluid in the body, it is conceivable that in the not-too-distant future they will be used as non-invasive biomarkers to monitor tumour progression and diagnose clinical relapse. There is also a therapeutic aspect, which has great potential. We need to move forward and understand how to block the release and circulation of miRNAs in exosomes, and develop methods that can be applied in humans.”
This publication originates as part of the existing research collaboration between the two institutes, within the Swiss-South Africa Joint Research Programme.
Prof. Carlo Catapano, highlights the importance of this collaboration between the ICGEB and the IOR, “Working together has given scientists at ICGEB and IOR the unique opportunity to expand the horizon of their research, including the possibility of verifying their working hypothesis on different experimental models and patient populations. This study is a clear example of integration of multiple expertise and resources of the research teams involved in the Swiss-South Africa collaborative program. Plasma exosomes and liquid biopsy approaches might be the new frontier – because of their easy access, low cost and high informational content – for diagnosis and monitoring of cancer patients worldwide.”