Yuki Nakamura
- kawaokashinpei3
- 4 日前
- 読了時間: 2分
Selected journal : Cell
Sensory neurons drive immune exclusion by stimulating a dense extracellular matrix in the breast cancer tumor microenvironment
What is the main question of the paper?
How do sensory neurons interact with the tumor microenvironment?
How did the anthor address the question?
■Step1
They demonstrated that in TNBC tumor tissue, sensory neurons accelerate tumor progression by reducing immune cell infiltration and promoting collagen deposition. Using a dataset of TNBC patients, they demonstrated that perineural invasion (PNI) in tumor tissue is a factor associated with poor prognosis, and that tumor tissue exhibiting PNI shows reduced levels of tumor-infiltrating lymphocytes (TILs) and CD4+ T cells. Using multiple mouse cancer models, they deteced that activation of sensory neurons reduces immune cell infiltration into tumor tissue and increases the number of cancer-associated fibroblasts (CAFs). In other words, sensory neurons play a critical role in the formation of an immunosuppressive TNBC tumor microenvironment.
■Step2
They revealed that NGF (nerve growth factor) derived from tumor cells promotes the secretion of CGRP (calcitonin gene-related peptide) by sensory neurons, and that CGRP binds to RMAP1 to activate CAF. Single-cell spatial transcriptomic analysis of TNBC tumor tissue revealed high NGF expression in tumor cells within the PNI region. Furthermore, co-culture experiments with tumor cells and sensory neurons showed that knocking down of NGF in tumor cells suppressed neuronal proliferation and CGRP secretion. In TNBC tumor tissue, CAFs were found to be abundant in the PNI region, and since CAFs were activated by the culture supernatant of sensory neurons, they identified CAFs as the target of sensory neurons. Furthermore, they detected that CGRP secreted by sensory neurons activates CAFs by binding to RMP1 expressed on CAFs.
■Step3
An approach targeting sensory neurons exhibits synergistic effects with immune checkpoint inhibition in TNBC. In a mouse model, ablation of sensory neurons enhanced the efficacy of anti-PD-1 therapy. Immunohistochemical analysis of TNBC tumor tissue confirmed that CGRP positivity is a factor associated with poor response to immune checkpoint inhibitors. CGRP inhibition is expected to have a synergistic effect with immune checkpoint inhibition.
What is the “strength” of the paper?
The approach is well-structured, starting with the involvement of sensory neurons, extracting factors leading to an immunosuppressive environment from omics data, and then validating these findings through factor-specific activation and knockout experiments. It is also interesting that the study demonstrates how inhibiting the upstream pathways of the identified factors leads to synergistic effects with immune checkpoint inhibitors, with a view toward clinical application.
Comment
I think the most interesting find of this study is its immediate translational relevance through drug repurposing. Instead of developing a new therapeutic from scratch, the authors targeted the CGRP-RAMP1 axis using Rimegepant, an FDA approved drug already widely used for migraines. Demonstrating that a well characterized headache medication can effectively dismantle the dense extracellular matrix and enhance the efficacy of anti-PD-1 therapy provides a pragmatic, a fast track strategy for clinical trials.
Comment by Xiaoran Ma
