DNA aptamers against exon v10 of CD44 inhibit breast cancer cell migration

Area of Science:

• Molecular Biology
• Cancer Research
• Cell Biology

Background:

• CD44 adhesion molecules are crucial for breast cancer progression, influencing growth, migration, and invasion.
• CD44's diverse functions arise from various splicing variants, with exon v10 implicated in promoting metastasis.
• The precise molecular mechanisms by which CD44 exon v10 promotes cancer cell migration remain unclear.

Purpose of the Study:

• To investigate the molecular mechanisms underlying CD44 exon v10's role in breast cancer cell migration.
• To test the hypothesis that CD44 forms a cell surface molecular complex via exon v10 to enhance breast cancer cell migration.
• To identify potential therapeutic targets for breast cancer based on CD44-mediated interactions.

Main Methods:

• Systematic Evolution of Ligands by Exponential Enrichment (SELEX) was used to select DNA aptamers that specifically bind to CD44 exon v10.
• Selected aptamers were screened for their ability to inhibit breast cancer cell migration.
• Co-immunoprecipitation and pull-down assays were employed to investigate molecular interactions between CD44 and other cell surface proteins, specifically EphA2.

Main Results:

• DNA aptamers specifically binding to CD44 exon v10 and inhibiting cell migration were successfully selected.
• Co-immunoprecipitation confirmed that EphA2 is co-precipitated with CD44.
• Pull-down assays demonstrated a direct binding interaction between recombinant CD44 exon v10 and EphA2, which was inhibited by the migration-blocking aptamers.

Conclusions:

• CD44 forms a molecular complex with EphA2 on the surface of breast cancer cells.
• This CD44-EphA2 complex plays a significant role in promoting breast cancer cell migration.
• The findings provide insights into breast cancer migration mechanisms and suggest CD44 exon v10-EphA2 interactions as a potential therapeutic target for breast cancer and other related cancers.