Spatially resolved transcriptomics reveals the architecture of the tumor-microenvironment interface

Area of Science:

• Cancer Biology
• Genomics
• Developmental Biology

Background:

• Tumor progression involves complex interactions between cancer cells and diverse non-tumorigenic cell types.
• Mechanisms by which tumors adapt to the cellular microenvironment at the tumor boundary remain largely unexplored.

Purpose of the Study:

• To investigate tumor-microenvironment interactions at the tumor boundary.
• To identify cellular adaptations enabling tumors to navigate and integrate into new host tissues.
• To characterize the molecular mechanisms underlying tumor-microenvironment communication.

Main Methods:

• Integration of spatially resolved transcriptomics, single-cell RNA sequencing (scRNA-seq), and single-nucleus RNA sequencing (snRNA-seq).
• Utilized a zebrafish model of melanoma to study tumor boundary dynamics.
• Analysis of gene expression patterns and protein localization in tumor-associated cells.

Main Results:

• Identification of a distinct "interface" cell state at the tumor boundary, comprising specialized tumor and microenvironment cells.
• Upregulation of a common set of cilia genes and enrichment of cilia proteins specifically at the tumor-microenvironment interface.
• Demonstrated that ETS-family transcription factors regulate cilia gene expression, suppressing it outside the interface.
• Observed conservation of this cilia-enriched interface in human melanoma patient samples.

Conclusions:

• The study reveals a conserved mechanism of tumor adaptation involving a specialized interface cell state.
• Cilia play a crucial role in mediating tumor-microenvironment interactions at the invasive front.
• Spatially resolved transcriptomics is a powerful tool for uncovering novel biological mechanisms at tissue interfaces.