New strategy to fight cancer developed

Scientists in southern China have developed a new strategy to fight cancer by forcing tumor cells to "expose themselves" to the body's immune system, potentially breaking through the defenses that allow many cancers to grow undetected.

The research findings were a collaborative effort by the Shenzhen Bay Laboratory and Peking University joint research team, led by Chen Peng, Zhang Heng and Xi Jianzhong.

The research, published in the journal Nature on Jan 7, describes a method that functions like an "intratumoral vaccine". It works by stripping away the molecules that cancer cells use to defend themselves and loading the cells with "viral flags" that act as targets for the immune system.

The human immune system is naturally equipped with T cells, which are specialized "soldier" cells designed to seek and destroy threats.

However, cancer cells are notoriously good at hiding. They often use immune checkpoints, which act like biological brakes, to tell T cells not to attack.

While current treatments called immune checkpoint blockage work by releasing these brakes, they often fail because the cancer remains too well hidden. In China, more than 60 percent of patients with non-small cell lung cancer do not respond to these current therapies. For melanoma, the response rate is less than 30 percent.

Zhang Heng, lead researcher at the Shenzhen Bay Laboratory, said the new findings involve technologies to identify cancer cells and force them to switch from a hidden state to becoming targets.

The strategy relies on a platform called GlueTAC, developed by Chen Peng's team in 2021, which serves as a general strategy to eliminate membrane targets. The newly developed iVAC molecule performs two specific tasks simultaneously: it removes the cancer's shield and plants a recognizable flag.

Specifically, the platform degrades a protein called PD-L1, the major immune checkpoint, cancer cell utilizes to ward off the immune system.

At the same time, it delivers antigens — essentially bits of recognizable protein — to the surface of the tumor. By planting these viral markers on the cancer, the researchers trick the body into thinking the tumor is a virus-infected cell. This activates a massive number of dormant T cells that already know how to fight viruses, prompting them to swarm and destroy the cancer cells.

Researchers validated the designed strategy in both animal models and patient-derived clusters, which are tiny, lab-grown versions of human cancer samples used for testing.

Zhang said the strategy has potential in treating colorectal, gastric, and liver cancers. The team is currently preparing for the transition to human drug development.

While the researchers are optimistic, the road to a shelf-ready drug still has a long way ahead.

Zhang estimates it could reach clinical trials in the next three to five years, noting that the process requires significant financial support and faces the usual uncertainties of medical research.

He said the team embraces an open and cooperative attitude in the hope that this new strategy can benefit cancer patients as soon as possible.