Profiling the tumor microenvironment proteome in prostate cancer using laser capture microdissection coupled to...

Area of Science:

• Proteomics
• Cancer Biology
• Molecular Pathology

Background:

• Laser capture microdissection (LCM) isolates specific cell populations from tissue sections.
• Understanding the tumor microenvironment requires precise cell-type-specific analysis.
• Advanced liquid chromatography-tandem mass spectrometry (LC-MS/MS) offers high-resolution proteomic profiling.

Purpose of the Study:

• To optimize and validate a workflow combining LCM with label-free LC-MS/MS.
• To enable systematic proteomic profiling of distinct cellular compartments within the tumor microenvironment.
• To assess the reproducibility and robustness of the integrated LCM-LC-MS/MS approach.

Main Methods:

• Tissue sectioning and standard LCM procedures.
• Soluble protein extraction from isolated benign epithelial, benign stromal, tumor epithelial, and tumor stromal cells.
• Protein digestion and analysis using advanced label-free LC-MS/MS.

Main Results:

• High correlation between technical replicates (R² = 0.99, mean % CV = 9.55% ± 8.73).
• Strong correlation between sample replicates (R² = 0.97, mean % CV = 13.83% ± 10.17).
• Demonstrated a robust and systematic method for proteomic analysis of microdissected cells.

Conclusions:

• The integrated LCM-LC-MS/MS workflow is highly reproducible and accurate.
• This method provides a powerful tool for dissecting the molecular heterogeneity of the tumor microenvironment.
• Enables detailed proteomic characterization of specific cell populations within complex tissue samples.