The fact that different types of tumors only spread to specific, preferred organs has been known to scientists for longer than a century. However, so far, research has not been able to shed light on the mechanisms of organ specific metastasis, i.e. the 1889 ‘soil and seed’ theory. A study recently published online by Nature Medicine, could now help explain this hypothesis by proposing a new mechanism to control cancer metastasis, offering a novel diagnostic and treatment potential.
The researchers from Weill Cornell Medical College, Memorial Sloan-Kettering Cancer Center, and their collaborators have been able to demonstrate how melanoma cancer cells release small ‘exosome’ vesicles, which travel to the bone, brain, liver and lung.
Exosome vesicles are microscopic particles, similar to ‘bubbles’ that contain various different molecules, including proteins and nucleic acids, which fuses with these organs, creating an environment that is perfect for spreading tumors.
According to the researchers, these harmful cancer exosomes have numerous effects. They trigger inflammation, promote leaky blood vessels and ‘educate’ bone marrow progenitor cells to get involved in the subsequent metastatic cascade.
The researchers state that these exosomes could prove beneficial in the diagnosis, prognosis and treatment of cancer, as these exosomes are readily measurable and accessible, due to the fact that they circulate in the blood.
Dr. David C. Lyden, the Stavros S. Niarchos Associate Professor in Pediatric Cardiology, associate professor of Pediatrics and Cell and Developmental Biology at Weill Cornell Medical College, who is also a pediatric neuro-oncologist at Memorial Sloan-Kettering Cancer Center, declares:
“The exosome profile could be useful in a number of ways – to help detect cancer early, to predict the aggressiveness of a patient’s tumor and response to chemotherapy or other treatments, and to understand the risk of cancer recurrence or spread before traditional methods would be able to.”
Dr. Jacqueline F. Bromberg, an associate attending physician at Memorial Sloan-Kettering Cancer Center and associate professor of Medicine at Weill Cornell, who studies breast cancer, adds:
“We believe each tumor type will have its own exosomal protein profile that will represent each tumor subtype. The exosomal proteins will be useful for prognosis in predicting which patients, including those who develop disease decades after their original diagnosis, will likely be at risk for future metastatic disease.”
According to Dr. Hector Peinado, instructor of molecular biology in the Department of Pediatrics at Weill Cornell Medical College, who led the study effective cancer therapy must be multi-layered, concluded: “If, in the future, we were able to find a way to control the ‘education’ of bone marrow cells, as well as the release and content of tumor exosomes in cancer patients, we would be able to curtail and reduce the spread of cancer, and improve the patient’s quality of life and survival.”
Written By Petra Rattue