Attack on KRAS

A quarter of all cancer cases can be treated with new immunotherapy

Svetlana Maslova, Hi-tech+

Scientists have developed an immunotherapy method aimed at a mutation present in 25% of all cancer cases. Impressive results of preclinical studies have already been obtained — cancer growth has been suppressed by more than 80% even in resistant tumors.

Scientists from the University of California at San Francisco presented a strategy to combat one of the most common cancer mutations in the KRAS gene. It is believed that KRAS mutations are associated with 25% of all cancer cases and until now there have been no effective tools to combat them.

One of the problems is that the surface of the KRAS protein is too smooth and drug molecules cannot bind to it. In addition, the protein acts inside the cell, not on the surface, which makes it difficult for the immune system to recognize mutations.

In search of a universal solution, scientists have developed an experimental drug ARS1620, which works in two directions. The drug not only blocks the mutation's effect on tumor growth, but also pulls the KRAS protein onto the cell surface. As a result, the protein and the drug bind and send a "eat me" signal to the immune system.

The scientists then tested billions of antibodies that would best recognize this signal. One antibody showed the necessary result. Soon, immunotherapy in combination with ARS1620 was tested on lung cancer cells.

The combined approach suppressed cancer growth by 82% compared to 44% when using ARS1620 alone. It is noteworthy that the therapy was effective even with the development of tumor resistance to ARS1620.

Article by Zhang et al. A covalent inhibitor of K-Ras(G12C) induces MHC class I presentation of haptenated peptide neoepitopes targeted by immunotherapy is published in the journal Cancer Cell – VM.

Now scientists plan to test the treatment for other types of tumors. Preclinical studies are still ongoing.

Portal "Eternal youth" http://vechnayamolodost.ru