Single-cell transcriptomic analysis reveals the landscape of epithelial-mesenchymal transition molecular heterogeneity in esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is a prevalent and highly lethal malignant disease. The epithelial-mesenchymal transition (EMT) is crucial in promoting ESCC development. However, the molecular heterogeneity of ESCC and the potential inhibitory strategies targeting EMT remain poorly understood. In this study, we analyzed high-resolution single-cell transcriptome data encompassing 209,231 ESCC cells from 39 tumor samples and 16 adjacent samples obtained from 44 individuals. We identified distinct cell populations exhibiting heterogeneous EMT characteristics and identified 87 EMT-associated molecules. The expression profiles of these EMT-associated molecules showed heterogeneity across different stages of ESCC progression. Moreover, we observed that EMT primarily occurred in early-stage tumors, before lymph node metastasis, and significantly promoted the rapid deterioration of ESCC. Notably, we identified SERPINH1 as a potential novel marker for ESCC EMT. By classifying ESCC patients based on EMT gene sets, we found that those with high EMT exhibited poorer prognosis. Furthermore, we predicted and experimentally validated drugs targeting ESCC EMT, including dactolisib, docetaxel, and nutlin, which demonstrated efficacy in inhibiting EMT and metastasis in ESCC. Through the integration of scRNA-seq, RNA-seq, and TCGA data with experimental validation, our comprehensive analysis elucidated the landscape of EMT during the entire course of ESCC development and metastasis. These findings provide valuable insights and a reference for refining ESCC clinical treatment strategies.