A patch that can shrink colon cancers might allow doctors to offer surgery-free therapies for the disorder.
Colorectal cancer is fourth deadliest forms of cancer with 42 000 reported cases in 2013, and surgery is usually the first stage of treatment.
But surgery rarely removes all the cancer cells, and the ones left behind can lead to recurrence of the disease. Moreover, therapeutic mainstays like chemotherapy can't tell apart healthy and cancerous cells, which can lead to damage to healthy tissue and side-effects.
"The patch is made out of soft hydrogel patch, similar to the gel that we eat, that sticks to the tumour like a glue and releases therapeutic cargo over time,” explains study lead author Natalie Artzi.
Once deployed, the patch, which is pre-loaded with a cocktail of chemotherapy drugs, is heated up to release its therapeutic cargo.
This is achieved by loading the drugs onto nanoparticles known as nanorods. These absorb infrared radiation, which is used to raise the gel temperature to trigger the drug discharge.
Also in the patch are nanospheres that do not heat up but instead contain packaged RNA or DNA 'gene therapy' agents capable of silencing cancer-causing oncogenes.
The researchers tested the patch on mice that had undergone surgery for colorectal cancer. Without the patch, tumours reappeared in 40% of the animals. Patch-treated mice, on the other hand, showed no cancer recurrences.
One must be cautious in extrapolating to humans data from animals, but the results do look encouraging...