Published online 10 July 2014
A group of researchers engineered a type of bone-specific nanoparticles that can deliver anticancer drugs with decreased side effects. The drug delivery system is designed to inhibit tumour progression in multiple myeloma patients.
Bone is a favourable microenvironment for tumour growth, and a frequent destination for metastatic cancer cells. However, limited treatment options exist for cancer within the bone.
During metastasis, cancer cells induce a sequence of changes in the microenvironment of bone marrow. They becomes packed with cancer cells that develop resistance to conventional chemotherapy and lead to bone fractures, pain, hypercalcaemia and consequently spinal cord and nerve compression syndromes.
The new study — published in PNAS
and led by Omid Farokhzad of Harvard Medical School, USA and King Abdulaziz University, Saudi Arabia — suggests that bone-homing nanomedicine, which is already used to increase bone volume and strength, can also manipulate the tumour cells and the bone marrow microenvironment to curb cancer growth with minimal side effects1
The scientists tested their hypothesis by treating mice with bone-targeted nanoparticles loaded with bortezomib, a proteasome inhibitor that has anti-tumour effects in patients with multiple myeloma, then injecting them with cancer cells.
The nanoparticles in question had three main components that earlier designs lacked: a targeting element that can selectively bind to bone mineral and have bone stimulatory properties, a stealth-providing layer to minimize immune recognition and enhance circulation, and finally a biodegradable polymeric material forming an inner core that can deliver therapeutics or diagnostics in a controlled manner.
“This platform could be used in many other cancer models to deliver many different anticancer agents,” Farokhzad says. “In addition, its utility goes beyond cancer and the technology can be utilized to deliver anti-infective agents in orthopaedics and dental procedures.”