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Functionalizing Liposomes with anti-CD44 Aptamer for Selective Targeting of Cancer Cells
Walhan Alshaer1,2,3, Hervé Hillaireau1,2, Juliette Vergnaud1,2
1†Univ Paris-Sud, Institut Galien Paris-Sud, LabEx LERMIT, Faculté de Pharmacie, 5 rue J.B. Clément, 92296 Châtenay-Malabry, France.
Abstract:
CD44 receptor protein is found to be overexpressed by many tumors and is identified as one of the most common cancer stem cell surface markers including tumors affecting colon, breast, pancreas, and head and neck, making this an attractive receptor for therapeutic targeting. In this study, 2'-F-pyrimidine-containing RNA aptamer (Apt1), previously selected against CD44, was successfully conjugated to the surface of PEGylated liposomes using the thiol-maleimide click reaction. The conjugation of Apt1 to the surface of liposomes was confirmed by the change in size and zeta potential and by migration on agarose gel electrophoresis. The binding affinity of Apt1 was improved after conjugation compared to free-Apt1. The cellular uptake for Apt1-Lip was tested by flow cytometry and confocal imaging using the two CD44(+) cell lines, human lung cancer cells (A549) and human breast cancer cells (MDA-MB-231), and the CD44(-) cell line, mouse embryonic fibroblast cells (NIH/3T3). The results showed higher sensitivity and selectivity for Apt1-Lip compared to the blank liposomes (Mal-Lip). In conclusion, we demonstrate a successful conjugation of anti-CD44 aptamer to the surface of liposome and binding preference of Apt1-Lip to CD44-expressing cancer cells and conclude to a promising potency of Apt1-Lip as a specific drug delivery system.
Insights
Researchers developed a novel drug delivery system by conjugating an anti-CD44 aptamer to liposomes. This Aptamer-Lip system demonstrates enhanced binding and selective targeting of CD44-expressing cancer cells, showing promise for cancer therapy.
Area of Science:
- Biotechnology
- Nanomedicine
- Cancer Research
Background:
- CD44 receptor protein is overexpressed in numerous tumors, serving as a common cancer stem cell marker.
- This overexpression makes CD44 an attractive target for cancer therapeutic strategies.
Purpose of the Study:
- To conjugate a 2'-F-pyrimidine-containing RNA aptamer (Apt1) against CD44 to PEGylated liposomes.
- To evaluate the binding affinity, cellular uptake, and targeting specificity of the resulting Aptamer-Lip (Apt1-Lip) system.
Main Methods:
- Thiol-maleimide click reaction was used for conjugating Apt1 to PEGylated liposomes.
- Characterization of Apt1-Lip included size, zeta potential, and agarose gel electrophoresis.
- Cellular uptake and targeting specificity were assessed using flow cytometry and confocal imaging on CD44(+) and CD44(-) cell lines.
Main Results:
- Successful conjugation of Apt1 to liposomes was confirmed.
- The binding affinity of the aptamer improved after conjugation.
- Apt1-Lip exhibited higher sensitivity and selectivity for CD44-expressing cancer cells compared to blank liposomes.
Conclusions:
- Demonstrated successful conjugation of an anti-CD44 aptamer to liposomes.
- Apt1-Lip shows preferential binding to CD44-expressing cancer cells.
- The Apt1-Lip system holds promise as a specific drug delivery platform for cancer therapy.
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