New 'intelligent' gel directly attacks cancer

Toronto: Scientists have developed a new injectable 'biogel' that can effectively deliver anti-cancer agents directly into cancerous tumours and kill them.

The technology, developed by researchers at the University of Montreal Hospital Research Centre (CRCHUM), has already been successfully tested in the laboratory.

If it works in patients, the therapy could one day revolutionise treatment for many forms of cancer, reseachers said.

Unlike "jello," the biogel is liquid at room temperature and gels at 37 degrees Celsius - human body temperature.

"The strength of this biogel is that it is compatible with anti-cancer immune cells. It is used to encapsulate these cells and eventually administer them using a syringe or catheter into the tumour or directly beside it," said Rejean Lapointe, co-author of a study.

"Instead of injecting these cells or anti-cancer drugs throughout the entire body via the bloodstream, we can treat the cancer locally. We hope that this targeted approach will improve current immunotherapies," said Lapointe.

One form of immunotherapy involves treating cancer patients with anti-cancer immune cells. This is called adoptive cell therapy.

These cells (T lymphocytes or T cells) are produced naturally by the body and have the ability to destroy cancer cells, but they are generally too weak and too few to eradicate the cancer alone.

T cells are therefore cultivated in the laboratory - often the patient's own cells - and then reinjected into the patient's blood.

While this form of immunotherapy has shown promising results in cases of advanced cancer, it is not always possible to generate enough T cells.

"With our technique, we only need to administer a few dozen million T cells, instead of the billions currently required. We can also administer compounds that 'awaken' the immune system to fight against cancer," said Lapointe, a professor at the University of Montreal.

The recipe for this promising biogel was developed by Sophie Lerouge, a researcher at the CRCHUM and professor at the Ecole de technologie superieure.

The compound is made from chitosane, a biodegradable material extracted from the shells of crustaceans, to which gelling agents are added.

"The formulation is liquid at room temperature, which facilitates its injection, but quickly takes on a cohesive and resistant structure at 37 degrees. We also needed a hydrogel that was non-toxic for the body and provided excellent survival and growth of the encapsulated cells," said Lerouge.

The biogel was successfully tested in several in vitro models, including melanoma and kidney cancer.

"The T lymphocytes in the gel are functional and can grow for two to three weeks, be released from the gel, and kill the cancerous cells," said Lapointe.

The research was published in the journal Biomaterials.