Tissue proteome analysis for profiling proteins associated with lymph node metastasis in gallbladder cancer

Area of Science:

• Oncology
• Proteomics
• Molecular Biology

Background:

• Lymph node (LN) metastasis is a critical prognostic factor in gallbladder cancer (GBC), correlating with significantly reduced survival rates.
• Despite standard treatments, LN-positive GBC patients exhibit a median survival of 7 months compared to ~23 months for LN-negative patients.

Purpose of the Study:

• To elucidate the molecular mechanisms underlying lymph node metastasis in gallbladder cancer.
• To identify specific protein biomarkers associated with LN metastasis in GBC.

Main Methods:

• iTRAQ-based quantitative proteomic analysis was performed on primary tumor tissues from LN-negative GBC, LN-positive GBC, and non-tumor controls.
• Bioinformatic analysis using the STRING database was employed to identify deregulated pathways.
• Western blot and immunohistochemistry (IHC) were used to validate protein expression levels.

Main Results:

• 58 differentially expressed proteins (DEPs) were identified in LN-positive GBC compared to LN-negative GBC and controls.
• Key proteins associated with LN metastasis include cytoskeletal proteins (KRT7, KRT19, VIM, SRI) and nuclear proteins (NPM1, HNRNPA2B1).
• Overexpression of KRT7 and SRI was confirmed in LN-positive GBC tissues via Western blot and IHC.

Conclusions:

• Proteomic analysis reveals distinct molecular signatures associated with lymph node metastasis in gallbladder cancer.
• Proteins such as KRT7 and SRI show significant overexpression in LN-positive GBC and warrant further investigation for diagnostic and therapeutic potential.
• Deregulated pathways including 'neutrophil degranulation' and 'HIF1 activation' may play roles in GBC lymph node metastasis.