Biotin-Linked Ursolic Acid Conjugates as Selective Anticancer Agents and Target-Identification Tools for Cancer...

Area of Science:

• Natural Products Chemistry
• Medicinal Chemistry
• Cancer Biology

Background:

• Ursolic acid (UA), a pentacyclic triterpenoid, possesses anticancer properties but suffers from poor solubility and bioavailability.
• These limitations hinder its therapeutic efficacy and impede molecular target identification.
• Developing strategies to enhance UA's properties is crucial for its clinical application.

Purpose of the Study:

• To synthesize novel biotin-conjugated ursolic acid derivatives to improve solubility and bioavailability.
• To evaluate the anticancer potential of these derivatives, particularly against bladder cancer.
• To identify molecular targets and mechanisms of action for enhanced ursolic acid derivatives.

Main Methods:

• Synthesis of biotin-conjugated UA derivatives (5a-d) via selective C-28 alkylation and biotinylation.
• Microwave-assisted synthesis was employed to improve reaction efficiency and purity.
• Cytotoxicity assays, apoptosis induction, reactive oxygen species (ROS) generation, and cell cycle analysis were performed.
• Proteomic profiling was utilized to identify protein interactions.

Main Results:

• Compound 5c demonstrated superior cytotoxicity and selectivity against bladder cancer cell lines compared to UA.
• 5c effectively induced apoptosis, increased ROS generation, and arrested cell cycle progression at the G1 phase.
• Proteomic analysis revealed that 5c interacts with proteins involved in ER stress, RNA processing, cytoskeletal remodeling, and metabolic regulation.

Conclusions:

• Biotinylated ursolic acid derivatives, especially compound 5c, represent a promising strategy to overcome UA's limitations.
• Compound 5c exhibits enhanced anticancer effects and provides insights into its molecular targets.
• These derivatives can serve as valuable chemical probes for advancing targeted cancer therapy research.