scholarly journals Near-Infrared Fluorescent Endoscopic Image-Guided Photothermal Ablation Therapy of Colorectal Cancer Using Dual-Modal Gold Nanorods Targeting Tumor-Infiltrating Innate Immune Cells in a Transgenic TS4 CRE/APCloxΔ468 Mouse Model

2019 ◽  
Vol 11 (24) ◽  
pp. 21353-21359 ◽  
Author(s):  
Elias Gournaris ◽  
Wooram Park ◽  
Soojeong Cho ◽  
David J. Bentrem ◽  
Andrew C. Larson ◽  
...  
2017 ◽  
Vol 114 (39) ◽  
pp. 10455-10460 ◽  
Author(s):  
Keehoon Jung ◽  
Takahiro Heishi ◽  
Joao Incio ◽  
Yuhui Huang ◽  
Elizabeth Y. Beech ◽  
...  

Antiangiogenic therapy with antibodies against VEGF (bevacizumab) or VEGFR2 (ramucirumab) has been proven efficacious in colorectal cancer (CRC) patients. However, the improvement in overall survival is modest and only in combination with chemotherapy. Thus, there is an urgent need to identify potential underlying mechanisms of resistance specific to antiangiogenic therapy and develop strategies to overcome them. Here we found that anti-VEGFR2 therapy up-regulates both C-X-C chemokine ligand 12 (CXCL12) and C-X-C chemokine receptor 4 (CXCR4) in orthotopic murine CRC models, including SL4 and CT26. Blockade of CXCR4 signaling significantly enhanced treatment efficacy of anti-VEGFR2 treatment in both CRC models. CXCR4 was predominantly expressed in immunosuppressive innate immune cells, which are recruited to CRCs upon anti-VEGFR2 treatment. Blockade of CXCR4 abrogated the recruitment of these innate immune cells. Importantly, these myeloid cells were mostly Ly6Clow monocytes and not Ly6Chigh monocytes. To selectively deplete individual innate immune cell populations, we targeted key pathways in Ly6Clow monocytes (Cx3cr1−/− mice), Ly6Chigh monocytes (CCR2−/− mice), and neutrophils (anti-Ly6G antibody) in combination with CXCR4 blockade in SL4 CRCs. Depletion of Ly6Clow monocytes or neutrophils improved anti-VEGFR2–induced SL4 tumor growth delay similar to the CXCR4 blockade. In CT26 CRCs, highly resistant to anti-VEGFR2 therapy, CXCR4 blockade enhanced anti-VEGFR2–induced tumor growth delay but specific depletion of Ly6G+ neutrophils did not. The discovery of CXCR4-dependent recruitment of Ly6Clow monocytes in tumors unveiled a heretofore unknown mechanism of resistance to anti-VEGF therapies. Our findings also provide a rapidly translatable strategy to enhance the outcome of anti-VEGF cancer therapies.


2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A794-A794
Author(s):  
Brittany Bunch ◽  
Autumn Joerger ◽  
Nino Mtchedlidze ◽  
Olivia Hoff ◽  
Kelly Guzman ◽  
...  

BackgroundThe tumor immune microenvironment comprises a heterogeneous collection of adaptive and innate immune cells that play a critical role in immune evasion and response to immunotherapeutic agents. cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway results in activation of various immune cells promoting innate immunity in addition to senescence of cancer cells. However, the mechanisms involved in response and resistance to cGAS-STING pathway activation is not well understood. Using Cellular Indexing of Transcriptomes and Epitopes by sequencing (CITE-seq), we explored immunological heterogeneity of tumor microenvironment in colorectal cancer and analyzed transcriptional and compositional changes of the immune landscape in response to cGAS-STING pathway activation alone and in combination with a PD-1 inhibitor nivolumab.MethodsAll human tumor samples were obtained with proper patient consent and IRB approval. Fresh patient tumor tissue was processed to generate uniform sized live 3D tumoroids measuring 150 µm in size. Treatment groups included a STING agonist, ADU-S100, alone or in combination with nivolumab. Here, we applied multi-modal CITE-seq profiling using the 10X Genomics platform to interrogate cellular responses to ex vivo treatment. Culture supernatants were collected for multiplex analysis of cytokine release in media. Additionally, flow cytometry was used to assess the activation profile of resident immune cells.ResultsMultimodal analysis of transcriptomes or proteomics at the single-cell level provided an unprecedented view of cellular diversity and enabled better understanding of how activation of STING pathway alone and in combination with nivolumab affects the TME in colorectal cancer. Flow cytometric analysis of immune cell populations isolated from 3D tumoroids demonstrated treatment mediated activation of tumor resident T-cells and changes in the innate immune cells, which coincided with marked changes in pro-and anti-inflammatory cytokine profiles determined by multiplex analysis.ConclusionsThese results demonstrate that the 3D-EXplore ex vivo tumoroid model provides a unique platform to assess the efficacy of immunotherapeutic agents and to develop novel therapeutic combinations. Furthermore, implementation of this platform in the clinical studies may also allow identifying clinically relevant biomarkers to enable the most effective treatment strategies for individual patients.


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