A new study describes how scientists are developing an intelligent biogel that delivers anti-cancer agents directly into tumors. Lab tests show the biogel performs well against tumor cells. If the same results can be achieved in patients, the biogel could revolutionize the treatment of many cancers.
The team, from the University of Montreal Hospital Research Centre (CRCHUM) in Canada, describes the study in the journal Biomaterials.
The researchers say the strength of their new biogel is that it is compatible with anti-cancer immune cells. It allows these cells or anti-cancer drugs to be injected directly into the cancer tumor instead of into the bloodstream.
Coauthor Réjean Lapointe, an associate professor of medicine, says:
“We hope that this targeted approach will improve current immunotherapies.”
Immunotherapy is a relatively new treatment method that enlists the immune system, or parts of it, to fight disease. One form of immunotherapy – called adoptive cell therapy – uses anti-cancer immune cells to treat cancer patients.
The aim of adoptive cell therapy is to boost the presence of T lymphocytes, or T cells, in the body. These cells can kill cancer cells, but there are generally not enough of them to eradicate the cancer.
Thus, in adoptive cell therapy, extra T cells are grown in the lab from samples extracted from the patient and then re-injected back into their body to boost their own reserves.
However, while the therapy has shown some promising results, it does not always produce enough T cells to kill the cancer completely. Also, it has to be administered with high doses of the hormone interleukin-2, which can be toxic.
‘Cellular reservoir’ for fighting cancer
Prof. Lapointe says the advantage of the injectable biogel is that you need fewer T cells:
“With our technique, we only need to administer a few dozen million T cells, instead of the billions currently required.”
Another advantage, he says, is that they can also administer compounds that enlist the immune system to help in the fight.
The researchers say the gel is non-toxic and provides an ideal environment in which the encapsulated immune cells can grow and replicate. It acts as a “cellular reservoir” for fighting cancer.
The team successfully tested the intelligent biogel in several test tube models of cancer tumors – including melanoma and kidney cancer.
Prof. Lapointe sums up the study:
“The T lymphocytes in the gel are functional and can grow for 2-3 weeks, be released from the gel, and kill the cancerous cells.”
He and his team made the biogel by adding gelling agents to chitosane, a biodegradable material extracted from the shells of crustaceans.
This produces a gel that is liquid at room temperatures – making it easy to inject. But once it is inside the body at 98.6 degrees Fahrenheit (37 degrees Celsius), the gel changes to become more cohesive and resistant, resembling a stretchy elasticated fabric, as shown in the following video:
The biogel now needs to be tested in animals before it can enter human trials. If it passes these tests, the researchers expect it to be available to cancer patients in a few years.
Meanwhile, in another recently published study, Medical News Today learned how researchers are developing lab-enhanced natural killer cells to eliminate cancer in lymph nodes. They have successfully tested them in mice, and should they work in humans, it could stop cancer using lymph nodes to spread to the rest of the body.
Written by Catharine Paddock, PhD