Radiotherapy in combination with CD47 blockade elicits a macrophage-mediated abscopal effect.

ABSTRACT: Radiation therapy is a mainstay of cancer treatment but does not always lead to complete tumor regression. Here we combine radiotherapy with blockade of the 'don't-eat-me' cell-surface molecule CD47 in small cell lung cancer (SCLC), a highly metastatic form of lung cancer. CD47 blockade potently enhances the local antitumor effects of radiotherapy in preclinical models of SCLC. Notably, CD47 blockade also stimulates off-target 'abscopal' effects inhibiting non-irradiated SCLC tumors in mice receiving radiation. These abscopal effects are independent of T cells but require macrophages that migrate into non-irradiated tumor sites in response to inflammatory signals produced by radiation and are locally activated by CD47 blockade to phagocytose cancer cells. Similar abscopal antitumor effects

SUBMITTER: Nishiga Y 

PROVIDER: S-EPMC9701141 | biostudies-literature | 2022 Nov

REPOSITORIES: biostudies-literature