Abstract
Introduction
Glioblastoma remains a lethal central nervous system malignancy with severe therapeutic limitations, largely due to poor blood-brain barrier permeability and neurotoxicity. Bromodomain-containing protein 4 (BRD4) is an epigenetic reader that drives oncogenic transcription, making it a key therapeutic target. Here, we present the rationale and experimental framework for YK-8-126, a newly synthesized small-molecule BRD4 inhibitor designed to prevent BRD4-acetylated histone interactions. Uniquely engineered with a core fluorophore, YK-8-126 is designed to act as a dual-function theranostic, enabling simultaneous target inhibition and direct intracellular tracking without secondary labeling.
Methods
Human U-87 glioblastoma cells will be treated with YK-8-126 to characterize intracellular localization using live-cell confocal microscopy. A time-course imaging study with 15-minute intervals will be performed to quantify cellular entry kinetics and signal persistence. Additionally, dose-dependent imaging assays will be conducted to establish key intracellular parameters, including fluorescence half-life (t1/2), concentration for half-maximal effect (EC50), duration of action, and steady-state cellular accumulation.
Results
We anticipate that YK-8-126 will demonstrate rapid, dose-dependent cellular entry and clear sub-cellular fluorescence signal localization within U-87 cells. Based on preliminary chemical modeling and structural design, we project robust signal accumulation with minimal photobleaching over serial imaging intervals. Successful execution of these kinetic models is expected to confirm efficient cell membrane permeability and predictable intracellular steady-state kinetics aligned with BRD4 targeting.
CONCLUSIONS: This study establishes an integrative approach to evaluate YK-8-126 as a novel theranostic candidate for glioblastoma. Demonstrating simultaneous intracellular visualization and targeted BRD4 inhibition will validate YK-8-126 as a promising lead compound for targeted neuro-oncology therapeutics.