Varintra E. Lander

Supplementary Figure S4 shows the enrichment of FAK signaling in senCAFs and the effect of FAK inhibition on senCAF number and phenotype, both in vivo and in vitro.

Supplementary Figure S7 shows the effects of senCAF depletion in mouse PDAC on T lymphocyte function using scRNA-seq, immunohistochemistry, and flow cytometry.

Supplementary Figure S6 shows the effects of senCAF depletion in mouse PDAC on TAM, cDC, and granulocyte function using scRNA-seq, immunohistochemistry, and flow cytometry.

Pancreatic ductal adenocarcinoma (PDAC) therapeutic resistance is largely attributed to a unique tumor microenvironment embedded with an abundance of cancer-associated fibroblasts (CAF). Distinct CAF populations were recently identified, but the phenotypic drivers and specific impact of CAF heterogeneity remain unclear. In this study, we identify a subpopulation of senescent myofibroblastic CAFs (SenCAF) in mouse and human PDAC. These SenCAFs are a phenotypically distinct subset of myofibroblastic CAFs that localize near tumor ducts and accumulate with PDAC progression. To assess the impact of endogenous SenCAFs in PDAC, we used an LSL-KRASG12D;p53flox;p48-CRE;INK-ATTAC (KPPC-IA) mouse model of spontaneous PDAC with inducible senescent cell depletion. Depletion of senescent stromal cells in genetic and pharmacologic PDAC models relieved immune suppression by macrophages, delayed tumor progression, and increased responsiveness to chemotherapy. Collectively, our findings demonstrate that SenCAFs promote PDAC progression and immune cell dysfunction.Significance: CAF heterogeneity in PDAC remains poorly understood. In this study, we identify a novel subpopulation of senescent CAFs that promotes PDAC progression and immunosuppression. Targeting CAF senescence in combination therapies could increase tumor vulnerability to chemo or immunotherapy.See related article by Ye et al., p. 1302.

Supplementary Figure S1 shows the presence of senescent cancer-associated fibroblast in human and mouse PDAC using multiplex immunohistochemistry.

Supplementary Figure S2 shows transcriptional signatures concerning SASPs, ECM/Matrisome, and immune functions in different subsets of CAFs in mouse PDAC, utilizing scRNA-seq.

Supplementary Table S1 shows the list of antibodies, reagents, mouse models, and software that are being utilized in this study.

Supplementary Figure S6 shows the effects of senCAF depletion in mouse PDAC on TAM, cDC, and granulocyte function using scRNA-seq, immunohistochemistry, and flow cytometry.

Supplementary Figure S4 shows the enrichment of FAK signaling in senCAFs and the effect of FAK inhibition on senCAF number and phenotype, both in vivo and in vitro.

Supplementary Figure S5 shows the strategy of senescent cell depletion in the KPPC-IA (INK-ATTAC) mouse model and its effects on different cell type numbers.