CSPG4 as a target for the specific killing of triple-negative breast cancer cells by a recombinant SNAP-tag-based antibody-auristatin F drug conjugate.

Abstract

PURPOSE:

Triple-negative breast cancer (TNBC) is phenotypic of breast tumors lacking expression of the estrogen receptor (ER), the progesterone receptor (PgR), and the human epidermal growth factor receptor 2 (HER2). The paucity of well-defined molecular targets in TNBC, coupled with the increasing burden of breast cancer-related mortality, emphasizes the need to develop targeted diagnostics and therapeutics. While antibody-drug conjugates (ADCs) have emerged as revolutionary tools in the selective delivery of drugs to malignant cells, their widespread clinical use has been hampered by traditional strategies which often give rise to heterogeneous mixtures of ADC products.

METHODS:

Utilizing SNAP-tag technology as a cutting-edge site-specific conjugation method, a chondroitin sulfate proteoglycan 4 (CSPG4)-targeting ADC was engineered, encompassing a single-chain antibody fragment (scFv) conjugated to auristatin F (AURIF) via a click chemistry strategy.

RESULTS:

After showcasing the self-labeling potential of the SNAP-tag component, surface binding and internalization of the fluorescently labeled product were demonstrated on CSPG4-positive TNBC cell lines through confocal microscopy and flow cytometry. The cell-killing ability of the novel AURIF-based recombinant ADC was illustrated by the induction of a 50% reduction in cell viability at nanomolar to micromolar concentrations on target cell lines.

CONCLUSION:

This research underscores the applicability of SNAP-tag in the unambiguous generation of homogeneous and pharmaceutically relevant immunoconjugates that could potentially be instrumental in the management of a daunting disease like TNBC.

• Authors: Neelakshi Mungra, Fleury A N Biteghe, Zaria Malindi, Allan M Huysamen, Maryam Karaan, Natasha S Hardcastle, Rubina Bunjun, Shivan Chetty, Krupa Naran, Dirk Lang, Wolfgang Richter, Roger Hunter, Stefan Barth
• Journal: Journal of cancer research and clinical oncology (J Cancer Res Clin Oncol) Vol. 149 Issue 13 Pg. 12203-12225 (Oct 2023) ISSN: 1432-1335 [Electronic] Germany
• PMID: 37432459 (Publication Type: Journal Article)
• Copyright: © 2023. The Author(s).

Chemical References

• Immunoconjugates
• chondroitin sulfate proteoglycan 4
• auristatin
• Single-Chain Antibodies
• CSPG4 protein, human
• Membrane Proteins
• Chondroitin Sulfate Proteoglycans

Topics

• Humans
• Immunoconjugates (pharmacology, chemistry)
• Triple Negative Breast Neoplasms (pathology)
• Single-Chain Antibodies (pharmacology)
• Cell Line, Tumor
• Membrane Proteins
• Chondroitin Sulfate Proteoglycans