Introduction

The invention relates to the selection, diagnostic and therapeutic use of nucleotide aptamers capable of binding specifically to exosomes isolated from breast cancer cells, to be used in liquid biopsies and for inhibiting tumor growth.

Technical features

Breast cancer is the most common type of cancer and a leading cause of death in women. Early diagnosis strongly affects patient survival, but available diagnostic strategies, such as mammography, are limited by the minimum tumor size required for visualization. The search for circulating markers is therefore essential for early diagnosis. Cancer cells have been shown to release large amounts of exosomes to communicate with each other and the surrounding stroma, affecting tumor growth and progression. Thus, exosomes represent an ideal diagnostic and therapeutic target.

We therefore isolated nucleic acid aptamers capable of specifically recognizing exosomes derived from breast cancer cells and inhibiting their uptake. Aptamers are small oligonucleotides able to bind their target with high affinity and specificity by folding themselves into tridimensional shapes and present many advantages as diagnostic and therapeutic tools. The isolated oligonucleotides show promising applications in both cancer diagnosis with liquid biopsy and therapy. Our approach can overcome the limitations of liquid biopsy based on markers other than exosomes (such as circulating cells and DNA) which, being present in limited quantities and showing low stability, require complex and expensive measurement technologies.

Possible Applications

• Early diagnosis of breast cancer in liquid biopsy;
• Innovative therapeutic strategies based on the specific removal of tumor exosomes and inhibition of tumor growth

Advantages

• Non-invasive detection and applicable to repeated screening;
• Rapid Detection (test in 24h);
• High affinity and specificity for breast cancer;
• Easy modifications;
• High stability and safety;
• Low variability between different preparations;
• Easy production and cost-effectiveness.