Biotinylated platinum(IV) complexes designed to target cancer cells

Area of Science:

• Medicinal Chemistry
• Cancer Biology
• Nanotechnology

Background:

• Platinum-based drugs like cisplatin are mainstays in cancer chemotherapy.
• Drug resistance and limited tumor specificity remain significant challenges.
• Biotinylation offers a strategy to enhance drug delivery and cellular uptake.

Purpose of the Study:

• To design and synthesize novel biotinylated platinum(IV) complexes.
• To evaluate their in vitro cytotoxicity and mechanisms of action.
• To investigate the role of biotinylation in cellular uptake and drug resistance.

Main Methods:

• Synthesis and characterization of three platinum(IV) complexes.
• In vitro cytotoxicity assays against various cancer cell lines.
• Assessment of cellular uptake and platinum accumulation.
• Molecular docking studies for biotin-streptavidin interactions.
• Western blot analysis for apoptosis-related proteins (Bax, cytochrome c, caspase-3).

Main Results:

• Platinum(IV) complexes demonstrated significant cytotoxicity, with complex 1 being 2.0-9.6 times more potent than cisplatin.
• Complexes were readily reduced to active platinum(II) species by biological reductants.
• Molecular docking confirmed biotin-streptavidin binding via noncovalent interactions.
• Biotinylation significantly enhanced platinum cellular uptake, particularly in cisplatin-resistant cells.
• Complex 1 induced apoptosis by upregulating Bax, releasing cytochrome c, and activating caspase-3.

Conclusions:

• Biotinylated platinum(IV) complexes represent a promising class of anticancer agents.
• Complex 1 exhibits superior potency and enhanced cellular uptake, overcoming cisplatin resistance.
• The observed mechanism involves the induction of apoptosis, highlighting the therapeutic potential of these novel compounds.