Cell-Autonomous Cxcl1 Sustains Tolerogenic Circuitries and Stromal Inflammation via Neutrophil-Derived TNF in Pancreatic Cancer

We have shown that KRAS-TP53 genomic coalteration is associated with immune-excluded microenvironments, chemoresistance, and poor survival in pancreatic ductal adenocarcinoma (PDAC) patients. By treating KRAS-TP53 cooperativity as a model for high-risk biology, we now identify cell-autonomous Cxcl1 as a key mediator of spatial T-cell restriction via interactions with CXCR2+ neutrophilic myeloid-derived suppressor cells in human PDAC using imaging mass cytometry. Silencing of cell-intrinsic Cxcl1 in LSL-KrasG12D/+;Trp53R172H/+;Pdx-1Cre/+(KPC) cells reprograms the trafficking and functional dynamics of neutrophils to overcome T-cell exclusion and controls tumor growth in a T cell-dependent manner. Mechanistically, neutrophil-derived TNF is a central regulator of this immunologic rewiring, instigating feed-forward Cxcl1 overproduction from tumor cells and cancer-associated fibroblasts (CAF), T-cell dysfunction, and inflammatory CAF polarization via transmembrane TNF-TNFR2 interactions. TNFR2 inhibition disrupts this circuitry and improves sensitivity to chemotherapy in vivo. Our results uncover cancer cell-neutrophil cross-talk in which context-dependent TNF signaling amplifies stromal inflammation and immune tolerance to promote therapeutic resistance in PDAC.

SIGNIFICANCE

By decoding connections between high-risk tumor genotypes, cell-autonomous inflammatory programs, and myeloid-enriched/T cell-excluded contexts, we identify a novel role for neutrophil-derived TNF in sustaining immunosuppression and stromal inflammation in pancreatic tumor microenvironments. This work offers a conceptual framework by which targeting context-dependent TNF signaling may overcome hallmarks of chemoresistance in pancreatic cancer. This article is highlighted in the In This Issue feature, p. 1275.

Immunological correlatives of durable responses and survival benefit for patients with cervical cancer in a trial of combined chemotherapy and immune therapy

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Background: Recurrent, metastatic, or persistent cervical cancer is largely an incurable disease due to lack of effective therapies. New treatment strategies are needed to provide long-term anti-tumor responses. We sought to gain insight into the immune pathways contributing to treatment response to immunotherapy. Methods: Fourteen patients with recurrent, persistent, or metastatic cervical cancer were enrolled in a single-arm phase II clinical trial (NCT03367871) with the combination of chemotherapy, bevacizumab and pembrolizumab regardless of tumor PD-L1 status. We designed a 40-color full spectrum flow cytometry panel to profile the protein markers of immune cells in peripheral blood mononuclear cells (PBMCs) at the single cell level to assess immunological correlates in blood with patients' anti-tumor responses. Results: In this trial with a cohort of predominantly Black and Hispanic patients (93%), 50% had durable responses to a combination therapy, and no difference was observed in the combined PD-L1 score (CPS) between responders and non-responders. With 40-color flow cytometry multiplex assays, we detected several differences between the non-responders and responders within the B and T cell populations. Within the B cell population, we observed a significant increase in the HLA+CD200hi B cells, a potentially suppressive cell subset, within the non-responders while among the responders we observed an increase in the number of HLA+CD200lo B cells. This HLA+CD200lo subset was mainly composed of IgD-CD27- memory B cells, a population suggested to have effector function. Moreover, the HLA+CD200hi B cell population contained a higher percentage of PD-L1 expressing cells than the HLA+CD200lo population, further supporting the suggestion that the HLA+CD200hi population may be an immunosuppressive subset. Within the T cell compartment, we observed an increase in the number of CD4+CD69+ T cells, which represent an activated CD4 T cell population, in the responder group compared to the non-responder group. The number of activated CD4+ T cells was observed to correlate (r = 0.5) with the HLA+CD200hi B cell subset. Conclusions: This study identified novel immunological correlates in peripheral blood that were associated with durable antitumor responses and survival benefit for cervical cancer patients. These results suggest a role for T-B collaboration in effective antitumor immunity induced by combination of chemotherapy and immune therapy against cervical cancer. Clinical trial information: NCT03367871.