13 January 2021
Molecule boosts cancer vaccine response
Published online 25 November 2020
Adding a small growth factor molecule to a cancer vaccine improves its potency against melanoma.
Flt3L is an endogenous growth factor for immune and blood-cell-producing progenitor cells. Now, a research team from universities in the US, and Sidra Medical and Research Center in Qatar, suggests that adding it to a cancer vaccine can improve its efficacy.
Cancer vaccines contain tumour antigens that can activate immune cells to target and kill cancer cells. But, most trials have failed to show clinical efficacy for several reasons, including their inability to adequately mobilize and activate dendritic cells, which process foreign antigens and present them on their surfaces in order to prime and activate cancer-killing T cells.
The research team found that adding Flt3L to an anti-melanoma cancer vaccine can bypass this obstacle.
Sixty patients with removed melanomas were divided into two cohorts. Both received the existing cancer vaccine, but only one group were given the added Flt3L.
The team found that Flt3L mobilized dendritic cells and ultimately improved the T cell response without causing significant adverse effects.
“These findings may change the approach of increasing efficacy in other cancer vaccines in the future,” says the study’s lead investigator, Nina Bhardwaj from the Icahn School of Medicine at Mount Sinai, US.
Bhardwaj N. et al. Flt3 ligand augments immune responses to anti-DEC-205-NY-ESO-1 vaccine through expansion of dendritic cell subsets Nat. Cancer https://doi.org/10.1038/s43018-020-00143-y (2020).