Changes in glycoprotein expression between primary breast tumour and synchronous lymph node metastases or...

Area of Science:

• Oncology
• Proteomics
• Cancer Metastasis

Background:

• Breast cancer is a heterogeneous disease with varying patient outcomes.
• Prognostic factors like tumor size, receptor status (ER, PgR, HER2), grade, Ki67, and age are routinely assessed.
• Lymph node involvement is critical for staging and guiding adjuvant therapy.

Purpose of the Study:

• To investigate molecular differences between primary breast tumors and their matched metastases.
• To identify proteins that change expression during the metastatic process.
• To explore the implications of these changes for treatment strategies.

Main Methods:

• Analysis of matched primary breast tumors with synchronous lymph node metastases and distant metastases.
• Pairwise tumor analysis within individuals to minimize inter-patient variability.
• Glycopeptide capture followed by label-free quantitative tandem mass spectrometry.
• Validation of differentially expressed proteins using immunohistochemistry.

Main Results:

• Significant changes in glycosylated protein expression were observed between primary tumors and matched metastases.
• Proteins involved in cell adhesion, migration, and immune response pathways were identified as differentially regulated.
• ATPIF1 and tubulin β-chain were validated as key differentially expressed proteins.

Conclusions:

• Cancer cells undergo molecular transformation during metastasis.
• The identified proteins provide insights into the molecular mechanisms of tumor spread.
• Treatment strategies should potentially be guided by the phenotype of metastatic sites.