Related Experiment Video
Updated: Jan 22, 2026

Author Spotlight: Advancing Alzheimer's Research – Exploring Early Detection and Multi-Omics Approaches
Published on: December 15, 2023
The Identification of LA-tumor associated macrophages in immune modulation via amyloid-beta precursor protein/CD74
Jian-Peng Wang1,2, Chen-Chen An2,3, Zi-Ning Wang2
1Department of Medical Oncology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China.
Background:
Tumor-associated macrophages (TAMs) play a critical role in cancer immune microenvironment, modulating immune evasion. The prognostic role of TAMs gives insights into the immune landscape and therapeutic targets in gastric cancer (GC).
Methods:
GC microenvironment was analyzed via single-cell and bulk RNA-seq data from public databases. TAM subtypes were then identified via dimensionality reduction and annotation under quality control. TAM differentiation and function were evaluated by pseudo-time analysis, cell communication, molecular docking, and key gene enrichment. A predictive model based on LA-TAM was established. Amyloid-β precursor protein (APP) expression level and its effect on macrophage programmed death-1 (PD-1) expression was validated in vitro.
Results:
In GC microenvironment, epithelial cells and fibroblasts were downregulated, while B cells, CD8+ T cells and myeloid cells were enriched. Among TAM subtypes, LA-TAM exhibited the potential of differentiation, metabolic reprogramming, and high plasticity. When LA-TAM interacts with endothelial cells, APP/Collagen pathway was activated, in which PD-1 expression was up-regulated by APP/CD74 activation. The LA-TAM-based predictive model showed significant performance among multiple cohorts (C-index >0.5, HR = 1.63, p<0.001). APP positively correlated with PD-1 expression. In GC THP-1 monocytes, APP was enriched and stimulated PD-1 expression.
Conclusion:
LA-TAM plays a key role in immune suppression and metabolic regulation in GC. Its key genes form a high-precision prognosis model, and endothelial cell-expressed APP may promote immune evasion by enhancing macrophage PD-1 expression, suggesting a potential target for immunotherapy.
Related Concept Videos
Amyloid Fibrils
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining,...
Antiepileptic Drugs: Modulators of Neurotransmitter Release Mediated by SV2A Protein
SV2A is a transmembrane glycoprotein located predominantly in the brain, modulating the release of neurotransmitters for neuronal communication. Both levetiracetam and brivaracetam exhibit a high affinity for...
Interactions Between Signaling Pathways
Convergence and divergence, and cross-talk between signaling pathways
Two distinct signaling pathways can converge on a single functional unit, which may either be a single protein or a complex of proteins. The response is either functionally distinct or synergistic between the two pathways but different from the response...
Notch Signaling Pathway
The Notch gene came into the limelight in 1914 after the discovery that its mutation in Drosophila melanogaster leads to a serrated (or "notched") wing margin phenotype. It was not...
Hedgehog Signaling Pathway
Insulin: The Receptor and Signaling Pathways

