Experimental nanoparticles could target cancers in bone tissue
An experimental treatment that uses microscopic balls – called ‘nanoparticles’ – could be used to target cancer cells within bones, according to a US study in mice.
"The findings support the idea that nanomedicine could be used to combine anti-cancer drug delivery and bone repair” - Dr Holger Auner, Cancer Research UK
Scientists from Brigham and Women's Hospital and Dana-Farber Cancer Institute found that when the nanoparticles, which have been designed to carry anti-cancer drugs, were engineered to home in on bone they slowed the growth of tumours in mice.
Experts agree that more research is needed, but the early-stage findings suggest this approach could be used to treat myeloma – a type of cancer where cells grow within the bone – or breast, prostate and lung cancers, which have the potential to spread to the bones.
Irene Ghobrial, MD, co-senior study author said that the findings represented a “proof of concept.”
"This work will pave the way for the development of innovative clinical trials in patients with myeloma to prevent progression from early precursor stages or in patients with breast, prostate or lung cancer who are at high risk to develop bone metastasis," she added.
To deliver the anti-cancer drugs directly to bone tissue, the team developed nanoparticles attracted to calcium, which concentrates in high levels in bones.
They did this by covering the surface of the nanoparticles with a substance known as alendronate, which binds to calcium. They then engineered these spheres to carry an anti-cancer drug called bortezomib.
When they tested the tiny particles in mice with myeloma they found that they could find and target the cancer cells present in the bone. The treatment slowed the growth of tumours while also strengthening the bone in these mice.
Dr Michaela Regan, co-lead study author, said: “Our engineered targeted therapies manipulate the tumour cells in the bone and surrounding microenvironment to effectively prevent cancer from spreading in bone.”
Cancer Research UK’s Dr Holger Auner, an expert in myeloma, welcomed the findings, saying that the study marked a step forward for using nanoparticles to treat cancer – something known as ‘nanomedicine’.
“This study is a very promising step towards the successful use of nanomedicine in cancer. And the findings support the idea that nanomedicine could be used to combine anti-cancer drug delivery and bone repair,” he said.
“It’s early days, and further studies will be needed to see if the same effects could be achieved in patients. But this approach could be adapted for many cancers that affect the bones, particularly multiple myeloma, which can cause considerable bone damage.”
The study was published in Proceedings of the National Academy of Sciences.
- Swami A, et al. (2014). Engineered nanomedicine for myeloma and bone microenvironment targeting, PNAS, DOI: 10.1073/pnas.1401337111