Elegant Delivery

Cancers are notorious for secreting chemicals that confuse the immune system and thwart biological defences.
To counter that effect, some cancer treatments try to neutralise the cancer’s chemical arsenal and boost a patient’s immune response–though attempts to do both at the same time are rarely successful.
Now, researchers have developed a novel system to simultaneously deliver a sustained dose of both an immune-system booster and a chemical to counter the cancer’s secretions, resulting in a powerful therapy that, in mice, delayed tumour growth, sent tumours into remission and dramatically increased survival rates.
The new immunotherapy incorporates well-studied drugs, but delivers them using nanolipogels (NLGs), a new drug transport technology the researchers designed. The NLGs are nanoscale, hollow, biodegradable spheres, each one capable of accommodating large quantities of chemically diverse molecules.
The spheres appear to accumulate in the leaky vasculature, or blood vessels, of tumours, releasing their cargo in a controlled, sustained fashion as the spherule walls and scaffolding break down in the bloodstream.
For the recent experiments, the NLGs contained two components: an inhibitor drug that counters a particularly potent cancer defence called transforming growth factor-β (TGF-β), and interleukin-2 (IL-2), a protein that rallies immune systems to respond to localised threats.
‘You can think of the tumour and its microenvironment as a castle and a moat,’ says Tarek Fahmy, the Yale University engineering professor and NSF
CAREER grantee who led the research. "The ‘castles’ are cancerous tumours, which have evolved a highly intelligent structure–the tumour cells and vasculature. The ‘moat’ is the cancer’s defence system, which includes TGF-β. Our strategy is to ‘dry-up’ that moat by neutralising the TGF-β. We do that using the inhibitor that is released from the nanolipogels. The inhibitor effectively stops the tumour