PD-L1 targeting and subclonal immune escape mediated by PD-L1 mutations in metastatic colorectal cancer.

ABSTRACT:

Background

In patients with microsatellite stable (MSS) metastatic colorectal cancer (mCRC), immune checkpoint blockade is ineffective, and combinatorial approaches enhancing immunogenicity need exploration.

Methods

We treated 43 patients with predominantly microsatellite stable RAS/BRAF wild-type mCRC on a phase II trial combining chemotherapy with the epidermal growth factor receptor antibody cetuximab and the programmed cell death ligand 1 (PD-L1) antibody avelumab. We performed next-generation gene panel sequencing for mutational typing of tumors and liquid biopsy monitoring as well as digital droplet PCR to confirm individual mutations. Translational analyses included tissue immunohistochemistry, multispectral imaging and repertoire sequencing of tumor-infiltrati

SUBMITTER: Stein A 

PROVIDER: S-EPMC8317124 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature