Cancer exports molecular 'saboteurs' [exosomes] to remotely disarm immune system

Andy · Apr 8, 2019

Posting as it shows what exosomes can be involved with.

But in their new paper Blelloch's group is suggesting a very different answer to this puzzle: PD-L1 is being mass-produced by these tumors, they found, but instead of displaying the protein on their surface, cancer cells export PD-L1 in molecular freighters known as exosomes. These PD-L1-packed exosomes sprout from cancer cells and travel through the lymphatic system or bloodstream to lymph nodes, the sites where immune cells are activated to protect the body. There, the PD-L1 proteins act as itinerant molecular saboteurs, remotely disarming immune cells and preventing them from locating tumors to mount an anti-cancer offensive.

So rather than shutting down the immune response at the tumor surface, exosomal PD-L1 can inhibit immune cells before they even arrive there. And unlike PD-L1 found on the tumor's surface, exosomal PD-L1, for unclear reasons, is resistant to existing checkpoint inhibitors.

"The standard model says that PD-L1 acts on immune cells that travel to the tumor niche, where they encounter this immune-suppressing protein," Blelloch said. "Our data suggests that this isn't true for many immunotherapy-resistant tumors. These tumors evade the immune system by delivering exosomal PD-L1 to lymph nodes, where they inhibit the activation of immune cells remotely. These findings represent a break from dogma."
Click to expand...

https://www.sciencedaily.com/releases/2019/04/190404143634.htm

Marky · Apr 8, 2019

Thats crazy. Cancer is such an asshole

Andy · Apr 9, 2019

NIH director's blog

New Target for Cancer Immunotherapy: Exosomes

It was once a central tenet of biology that RNA molecules did their work inside the cell. But it’s now clear that RNA molecules are also active outside the cell, with potentially major implications for our health. To learn more about these unrecognized roles, the NIH Common Fund has launched the Extracellular RNA (exRNA) Communication Program.
Click to expand...

https://directorsblog.nih.gov/2019/04/09/new-target-for-cancer-immunotherapy-exosomes/

andypants · Apr 10, 2019

Oooo, if ME/CFS research could latch onto cancer research we'd be set

Log in or Sign up

Cancer exports molecular 'saboteurs' [exosomes] to remotely disarm immune system

Andy Committee Member

Marky Senior Member (Voting Rights)

Andy Committee Member

andypants Senior Member (Voting Rights)

Share This Page

Log in or Sign up

Cancer exports molecular 'saboteurs' [exosomes] to remotely disarm immune system

Andy Committee Member

Marky Senior Member (Voting Rights)

Andy Committee Member

andypants Senior Member (Voting Rights)

Share This Page

Useful Searches