Cancer Cell. Prostate cancer spreads by sending messages to other organs. An experimental technique hijacks them to monitor evolution of the disease and response to treatment

Fluorescence imaging visualization of extracellular vesicles of prostate cancer (green) nesting in bone (red) . The vesicles are seen to reach metastatic organs typical of prostate cancer. / Héctor Peinado, Elena Castellano-Sanz. CNIO.

Cells communicate with each other by releasing nanoparticles or vesicles filled with cellular products such as proteins or even genetic material – DNA and RNA – into their environment. A decade ago, Héctor Peinado‘s group at the Spanish National Cancer Research Centre (CNIO) discovered that these vesicles, when produced by tumour cells, help spread the cancer, generating a biochemical environment favourable to metastasis in certain organs.

In other words, the nanoparticles act as messengers for the tumour, paving the way for it to colonise another organ.

Peinado has spent years studying whether intercepting the message – capturing the vesicles and analysing their content- helps detect cancer earlier or improve its treatment. If so, it would be good news, because all it takes to access the messenger nanoparticles is a blood test, the sought-after liquid biopsy.

Prostate cancer messenger vesicles

Now, a study led by researchers at the Vall d’Hebron Institute of Oncology (VHIO) with which Peinado’s group at CNIO is collaborating, has found that, indeed, in patients with metastatic prostate cancer, the analysis of the vesicles secreted by tumour cells does provide information on the response to treatment.

The research, published today in Cancer Cell, describes a new tool, based on liquid biopsy, to monitor the expression of tumour genes from the mRNA contained in the vesicles.

Joaquín Mateo, medical oncologist at Vall d’Hebron University Hospital, head of the VHIO Prostate Cancer Translational Research Group and senior author of this study, explains that “this opens the way to identify biomarkers to analyse the response to treatment and the acquisition of resistance, and thus make the most appropriate clinical decisions at each stage of the disease”.

For Peinado, the study shows that “reading the message carried by circulating tumour-derived vesicles could allow us to anticipate the progression of metastatic prostate cancer”. The new method “allows non-invasive detection and monitoring of the response to treatment. In metastatic prostate cancer this is essential”.

Prostate cancer is the second most diagnosed cancer in Spain, the first in men. Most are diagnosed in early stages and are curable. But some end up developing metastases, or have metastases from the beginning. In these cases, the tumour can adapt to treatment; monitoring this tumour adaptation can help guide treatment at each stage of the disease.

Untapped potential

Irene Casanova, associate researcher in the Prostate Cancer Translational Research Group and first author of this article, recalls that “the potential of tumour extracellular vesicles as a source of relevant DNA and RNA biomarkers remains largely unexplored”.

“Our work aims to develop a new liquid biopsy application to analyse circulating extracellular vesicles and, from a multi-omics approach, to perform genomic and transcriptomic characterisation of the tumour,” she adds.

Genomic and transcriptomic profiling of the tumour

The work is based on the analysis of serial plasma samples from 53 patients with metastatic prostate cancer, treated with hormone therapy or chemotherapy. The researchers analysed the circulating DNA, as well as the DNA and RNA contained in the extracellular vesicles. This analysis confirms that the extracellular vesicles contain genetic material derived from the tumour whose information allows us to know the mutations present in the tumour cells, as well as to know which tumours will have a worse evolution.

Researchers from the Príncipe Felipe Research Centre (CIPF) in Valencia are also collaborate in the study.

Back to the news