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The efficacy of cancer immunotherapy is greatly restricted by insufficient infiltration of cytotoxic T lymphocytes and immunosuppressive microenvironment in tumor tissue. Here a potent strategy to address the limitations by combination therapy of chemokine (CXCL9) with BRD4‐PROTAC (dBET6) using the unique mixed‐shell polymeric micelle (MSPM)‐based nanochaperone (nChap) delivery platform is reported. CXCL9 significantly enhances the intratumoral infiltration of CD8+ T cells while dBET6 induces tumor cell immunogenic cell death (ICD) and downregulates the interferon‐γ (IFNγ)‐triggered programmed death ligand 1 (PD‐L1) expression, synergizing to boost robust T cell‐dependent antitumor immunity responses to enhance cancer immunotherapy is demonstrated. Moreover, this nano‐CXCL9/dBET6 exhibits reduced systemic toxicity, prolonged half‐life, and enhanced tumor accumulation in comparison to free drugs. This study provides a promising strategy for efficient cancer immunotherapy. [ABSTRACT FROM AUTHOR]

Cellular senescence contributes to cancer pathogenesis and immune regulation. Using the LASSO Cox regression, we developed a 12‐gene prognostic signature for lung adenocarcinoma (LUAD) from The Cancer Genome Atlas (TCGA) and a Gene Expression Omnibus (GEO) dataset. We assessed gene expression, drug sensitivity, immune infiltration, and conducted cell line experiments. High‐risk LUAD patients showed increased mortality risk and shorter survival (P < 0.001). Senescence‐related gene analysis indicated differences in protein phosphorylation and DNA methylation between normal individuals and LUAD patients. The high‐risk group showed a positive association with PD‐L1 expression (P = 0.003). Single‐cell sequencing data suggested PEBP1 might significantly impact T cell infiltration. We predicted potential sensitive compounds for 12 senescence genes and found GAPDH promoted cell line proliferation. We established a novel prognostic system based on a newly identified senescence gene. High‐risk patients had elevated immunosuppressive markers, and PEBP1 might influence T cell infiltration significantly. GAPDH, expressed at higher levels in tumors, could affect cancer progression. Our drug prediction model may guide treatment selection. [ABSTRACT FROM AUTHOR]

The anti‐tumor immune response relies on interactions among tumor cells and immune cells. However, the molecular mechanisms by which tumor cells regulate DCs as well as DCs regulate T cells remain enigmatic. Here, the authors identify a super signaling complex in DCs that mediates the Arf1‐ablation‐induced anti‐tumor immunity. They find that the Arf1‐ablated tumor cells release OxLDL, HMGB1, and genomic DNA, which together bound to a coreceptor complex of CD36/TLR2/TLR6 on DC surface. The complex then is internalized into the Rab7‐marked endosome in DCs, and further joined by components of the NF‐κB, NLRP3 inflammasome and cGAS‐STING triple pathways to form a super signal complex for producing different cytokines, which together promote CD8+ T cell tumor infiltration, cross‐priming and stemness. Blockage of the HMGB1‐gDNA complex or reducing expression in each member of the coreceptors or the cGAS/STING pathway prevents production of the cytokines. Moreover, depletion of the type I IFNs and IL‐1β cytokines abrogate tumor regression in mice bearing the Arf1‐ablated tumor cells. These findings reveal a new molecular mechanism by which dying tumor cells releasing several factors to activate the triple pathways in DC for producing multiple cytokines to simultaneously promote DC activation, T cell infiltration, cross‐priming and stemness. [ABSTRACT FROM AUTHOR]

T lymphocyte recruitment and infiltration promises to suppress the most devastating metastatic tumors for immunotherapy. However, the immune privilege and low vaccine immunogenicity usually reduces the presence of lymphocytes in tumors, especially for invading metastatic clusters. Here, an adhesive catalytic nanoreservoir (CN) containing manganese dioxide (MnO2) and catechol‐functionalized magnetic metal organic framework for the antigens capture and delivery is reported. The intravenously injected CN accumulates at tumor via the marginated target and in situ forming gel for antigen capture. At tumor site, CN releases Mn2+ for redox reactions by depleting glutathione (GSH) and Fenton‐like activity, i.e., chemodynamic therapy (CDT). Accompanying with hyperthermia, CDT promote the tumor to release the tumor‐associated antigens including neoantigens and damage‐associated molecular patterns. Then, the gels with catechol groups act as antigen reservoirs and deliver the autologous tumor‐associated antigens to dendritic cells, achieving sustained immune stimulation. The in situ‐forming catalytic nanoreservoir at lung metastasis as a magnetothermal‐induced antigen reservoir effectively inhibited the tumor in 60 days and increased the survival rate. [ABSTRACT FROM AUTHOR]

Programmed death-ligand 1 (PD-L1) blockade has revolutionized the prognosis of several cancers, but shows a weak effect on pancreatic cancer (PC) due to poor effective immune infiltration. Chemokine C-C motif ligand 21 (CCL21), a chemokine promoting T cell immunity by recruiting and colocalizing dendritic cells (DCs) and T cells, serves as a potential antitumor agent in many cancers. However, its antitumor response and mechanism combined with PD-L1 blockade in PC remain unclear. In our study, we found CCL21 played an important role in leukocyte chemotaxis, inflammatory response, and positive regulation of PI3K-AKT signaling in PC using Metascape and gene set enrichment analysis. The CCL21 level was verified to be positively correlated with infiltration of CD8+ T cells by the CIBERSORT algorithm, but no significant difference in survival was observed in either The Cancer Genome Atlas or the International Cancer Genome Consortium cohort when stratified by CCL21 expression. Additionally, we found the growth rate of allograft tumors was reduced and T cell infiltration was increased, but tumor PD-L1 abundance elevated simultaneously in the CCL21-overexpressed tumors. Then, CCL21 was further verified to increase tumor PD-L1 level through the AKT-glycogen synthase kinase-3β axis in human PC cells, which partly impaired the antitumor T cell immunity. Finally, the combination of CCL21 and PD-L1 blockade showed superior synergistic tumor suppression in vitro and in vivo. Together, our findings suggested that CCL21 in combination with PD-L1 blockade might be an efficient and promising option for the treatment of PC. [ABSTRACT FROM AUTHOR]