Researchers use spatial transcriptomics to uncover tumor microenvironment patterns linked to remedy response in non-small-cell lung most cancers
In a latest examine revealed in Nature Genetics, researchers characterised the spatial mobile compositions and tumor cell states of the tumor microenvironment (TME) in non-small cell lung most cancers (NSCLC).
Background
Immune checkpoint blockade (ICB) remedy has revolutionized NSCLC care, even curing advanced-stage illness. Though neoadjuvant immunochemotherapy is more practical than ICB alone, many NSCLC sufferers develop resistance to neoadjuvant immunochemotherapy, and the underlying resistance mechanisms are unclear.
The TME encompasses various stromal and immune cells that contribute to immune escape and tumor progress. Single-cell RNA sequencing (scRNA-seq) has been extensively used to discover resistance-linked options. These research indicated that whereas neoadjuvant ICB remedy can partially reprogram the TME and elevate T cell infiltration, the surroundings stays suppressive, limiting efficacy.
The examine and findings
Within the current examine, researchers profiled the spatial group and mobile composition of tumor cells and the TME earlier than and after neoadjuvant ICB-chemotherapy in non-responders and responders. First, they profiled tumor samples from 19 NSCLC sufferers earlier than and after neoadjuvant anti-PD-1 remedy and chemotherapy utilizing scRNA-seq. Moreover, spatial transcriptomic analyses had been carried out on treatment-naïve and post-treatment samples.
Six sufferers had been responders, whereas 13 had been non-responders. Following high quality management, transcriptomes of greater than 232,000 particular person cells had been derived. Unsupervised clustering was carried out to discover mobile compositions. This yielded almost 65,000 epithelial cells, which shaped two main clusters (presumably malignant and regular cells). Additional unsupervised analyses revealed 21 epithelial subclusters (13 malignant and eight regular).
Malignant cells had been eradicated within the epithelial cell compartment in responders after ICB-chemotherapy. There have been modifications in stromal and immune compartments. Most cancers cell states had been examined utilizing scRNA-seq information. These cells had been stratified into 14 subsets and annotated through gene set enrichment evaluation. Cell states clustered into two teams. One group comprised cell cycle-related, squamous, and nuclear issue erythroid 2-related issue 2 (NRF2) goal cell states.
The opposite group comprised alveolar, estrogen, interferon (IFN), coagulation and extracellular matrix cell states. Notably, most cancers cell states had been extremely anticorrelated in these teams. Some states (IFN, estrogen, and alveolar) had been linked to extended survival, whereas others (squamous, cell cycle, and NRF2 goal) had been associated to poor survival throughout sufferers in a special cohort.
Subsequent, the group in contrast cell proportions between non-responders and responders on the tumor boundary pre- and post-therapy. Non-responders had the next proportion of collagen kind XI alpha 1 chain-positive (COL11A1+) cancer-associated fibroblasts (CAFs) and a decrease proportion of cluster of differentiation 8 (CD8) T cells than responders. In non-responders, COL11A1+ CAFs aggregated at remoted tumor boundaries however decreased in stromal areas away from malignant cells.
Against this, alcohol dehydrogenase 1B-positive (ADH1B+) CAFs had been enriched in tumor stromal areas. Subsequent, the researchers examined associations between T cells and COL11A1+ CAFs. The abundance of COL11A1+ CAFs round malignant cells correlated negatively with T-cell abundance in all samples containing malignant cells. Additional, the group assessed whether or not the abundance of COL11A1+ CAFs could possibly be a prognostic marker for NSCLC.
Hazard ratios for cohorts on ICB remedy had been greater than these of chemotherapy and treatment-naïve cohorts. Subsequent, they centered on the connection between COL11A1+ CAFs and macrophages in NSCLC, as prior research have steered that macrophage-CAF interactions promote tumor progress in liver and colon cancers. scRNA-seq information confirmed a constructive affiliation between secreted phosphoprotein 1-positive (SPP1+) macrophages and COL11A1+ CAFs.
Like COL11A1+ CAFs, SPP1+ macrophages had been greater in non-responders earlier than and after remedy, collected at tumor boundaries, and had decrease abundance in stromal areas away from the tumor. Multiplex immunohistochemistry staining revealed that SPP1+ macrophages localized with COL11A1+ CAFs on the tumor boundary, whereas T cells had been blocked by the mixture of those cells. Tertiary lymphoid buildings (TLSs) had been prevalent within the TME following ICB-chemotherapy.
Additional, the group characterised the maturation technique of TLSs. The maturation phases of TLSs, as indicated by k-means clustering, had been early lymphoid aggregates, activated TLSs, declining TLSs, and late TLSs. TLS maturation states had been remarkably various amongst sufferers with completely different responses. Activated TLSs had been related to improved prognosis. Extra analyses indicated that hypoxic TME could suppress TLS growth.
Conclusions
Collectively, the examine introduced a high-resolution spatial mobile and molecular atlas of the NSCLC TME earlier than and after neoadjuvant ICB-chemotherapy. The group revealed 14 distinct states of most cancers cells in NSCLC specimens. Most cancers cell states related to IFN-γ and NRF2 targets had been linked to favorable and poor responses to ICB-chemotherapy, respectively.
Non-responders confirmed considerably extra considerable COL11A1+ CAFs than responders. COL11A1+ CAFs had been primarily localized at tumor boundaries after remedy and will block contact between immune cells and tumor cells. General, the outcomes underscore the potential of therapies concentrating on a number of TME parts, opening avenues to develop combinatorial therapies.
Journal reference:
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Yan Y, Solar D, Hu J, et al. Multi-omic profiling highlights elements related to resistance to immuno-chemotherapy in non-small-cell lung most cancers. Nature Genetics, 2024. doi: 10.1038/s41588-024-01998-y https://www.nature.com/articles/s41588-024-01998-y