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A cyclic-RGD-BioShuttle functionalized with TMZ by DARinv "Click Chemistry" targeted to αvβ3 integrin for therapy
Klaus Braun1, Manfred Wiessler, Rüdiger Pipkorn
1German Cancer Research Center, Dept. of Imaging and Radiooncology, INF 280, D-69120 Heidelberg, Germany. k.braun@dkfz.de
Abstract:
Clinical experiences often document, that a successful tumor control requires high doses of drug applications. It is widely believed that unavoidable adverse reactions could be minimized by using gene-therapeutic strategies protecting the tumor-surrounding healthy tissue as well as the bone-marrow. One new approach in this direction is the use of "Targeted Therapies" realizing a selective drug targeting to gain effectual amounts at the target site, even with drastically reduced application doses. MCF-7 breast cancer cells expressing the α(v)β(3) [alpha(v)beta(3)] integrin receptor are considered as appropriate candidates for such a targeted therapy. The modularly composed BioShuttle carrier consisting of different units designed to facilitate the passage across the cell membranes and for subcellular addressing of diagnostic and/or therapeutic molecules could be considered as an eligible delivery platform. Here we used the cyclic RGD-BioShuttle as a carrier for temozolomide (TMZ) at the α(v)β(3) integrin receptor realizing local TMZ concentrations sufficient for cell killing. The IC50 values are 12 µMol/L in the case of cRGD-BioShuttle-TMZ and 100 µMol/L for underivatized TMZ, which confirms the advantage of TMZ reformulation to realize local concentrations sufficient for cell killing. Our paper focuses on the design, synthesis and application of the cRGD-BioShuttle conjugate composed of the cyclic RGD, a α(v)β(3) integrin-ligand, ligated to the cytotoxic drug TMZ. The ligation was carried out by the Diels Alder Reaction with inverse electron demand (DAR(inv)).
Insights
Targeted therapies using cyclic RGD-BioShuttle successfully delivered temozolomide (TMZ) to alpha(v)beta(3) integrin receptors on breast cancer cells. This enhanced drug delivery significantly improved therapeutic efficacy, reducing required doses and minimizing side effects.
Area of Science:
- Biomedical Engineering
- Drug Delivery Systems
- Oncology
Background:
- High-dose chemotherapy often leads to adverse reactions, necessitating strategies to protect healthy tissues.
- Targeted therapies offer a promising approach to selectively deliver drugs to tumor sites, reducing systemic toxicity.
- MCF-7 breast cancer cells, expressing alpha(v)beta(3) integrin receptors, are suitable targets for novel drug delivery systems.
Purpose of the Study:
- To design, synthesize, and evaluate a novel drug delivery platform for targeted cancer therapy.
- To conjugate the cytotoxic drug temozolomide (TMZ) to a cyclic RGD-BioShuttle carrier for enhanced delivery to alpha(v)beta(3) integrin receptors.
- To demonstrate the improved efficacy of the targeted drug conjugate compared to the free drug.
Main Methods:
- Development of a modular BioShuttle carrier system for cellular membrane passage and subcellular targeting.
- Ligation of cyclic RGD (alpha(v)beta(3) integrin ligand) to temozolomide (TMZ) using the Diels-Alder reaction with inverse electron demand (DAR(inv)).
- In vitro assessment of the cyclic RGD-BioShuttle-TMZ conjugate's efficacy in killing MCF-7 breast cancer cells.
Main Results:
- The cyclic RGD-BioShuttle effectively delivered TMZ to alpha(v)beta(3) integrin-expressing cells.
- The IC50 value for the cRGD-BioShuttle-TMZ conjugate was 12 µMol/L, significantly lower than that of underivatized TMZ (100 µMol/L).
- This reformulation demonstrated sufficient local TMZ concentrations for effective cancer cell killing.
Conclusions:
- The cyclic RGD-BioShuttle serves as an effective delivery platform for targeted cancer therapy.
- Conjugating TMZ to the cRGD-BioShuttle enhances its potency against alpha(v)beta(3) integrin-expressing cancer cells.
- This targeted approach holds potential for reducing chemotherapy doses and associated side effects.
