Novel Way of Reprogramming Immune Cells Effective in Clearing Devastating Melanoma

Researchers from the University of Bristol discovered a novel way of reprogramming immune cells to shrink or kill cancer cells that is effective in treating devastating skin cancer, called melanoma. The reprogramming method demonstrates a new way to clear early-stage pre-cancerous and late-stage tumor cells.

The discovery is published in the study, titled "Macrophage Reprogramming with Anti-miR223-Loaded Artificial Protocells Enhances In Vivo Cancer Therapeutic Potential," in Advanced Science.

(Photo : American Cancer Society/Getty Images)
Detail of a person with a malignant melanoma, which is a malignant skin tumor that involves the skin cells that produce pigment.

Using Protocells To Reprogram Immune Cells

Professor Paul Martin from the university's School of Biochemistry and one of the study's lead authors explained what happens between the immune system and cancer cells, Medical Xpress reported.

He said that immune cells have a surveillance capacity that can detect pre-cancerous cells arising at any tissue site in the body. However, immune cells are often subverted by cancer cells when they attack and instead of killing the harmful cells, they end up nourishing them and encouraging their growth.

In the study, they want to test whether it is possible to reprogram immune cells to kill cancer cells rather than nurture them. They used miniature artificial capsules called protocells that are designed to deploy reprogramming cargoes to the white blood cells.

The team showed they were able to transform these cells, which can be effective at shrinking and killing melanoma cells. Their experiments reveal that it was effective in both animal and human immune cells.

They tested it on zebrafish larvae to see how inflammatory immune cells interact with cancer cells in different ways that are not possible with their own tissues.

Protocells loaded with anti-miR223 molecules that interfere with signaling machinery in inflammatory immune cells work effectively to drive altered immune cell-cancer cell interactions, slowing the growth of cancerous cells and killing tumors.

Testing to See if It Will Lead to New Therapeutic Strategies

The research is the first study to test the capacity of protocells to deliver cargo for reprogramming immune cells and offer promise for developing novel cancer immunotherapies, per a similar report from the News Medical Life Sciences.

They repeated the experiment in adult fish with tailfin melanomas to see whether the approach they used in reprogramming immune cells can be upscaled as a feasible strategy for shrinking and killing larger and growing cancer cells. They found that it significantly inhibited melanoma cell growth.

Then they tested in the protocells to deliver 'reprogramming' anti-miR223 cargoes in humans using an in vitro assay with primary human immune cells from the Toye lab. Results showed that the protocells effectively deliver and reprogrammed human immune cells to become more persistent against cancer cells.

Professor Stephen Mann from Bristol's School of Chemistry said that the findings highlight the therapeutic benefits of harnessing host immunity to eliminate cancer cells and demonstrate the feasibility of using protocells to deliver reprogramming anti-miR223 cargoes in human immune cells.