Targeted delivery of nuclear targeting probe for bladder cancer using cyclic pentapeptide c(RGDfK) and acridine orange.

PURPOSE: Both cyclic pentapeptide c(RGDfK) and acridine orange (AO) exhibit antitumor effects and cell permeability. This study aimed to evaluate the nuclear targeting efficiency and safety of the nuclear targeting probe for bladder cancer (BCa) synthesized by c(RGDfK) and AO. METHODS: The nuclear targeting probe AO-(cRGDfK)2 was synthesized from AO hydrochloride, azided c(RGDfK), and a near-infrared skeleton synthesized via click chemistry reactions. The effect of the AO-(cRGDfK)2 probe on cell viability was assessed in BCa 5637 cells. The tumor cell targeting efficacy of the AO-(cRGDfK)2 probe was evaluated in BCa cells in vitro and in tumor-bearing mice in vivo. Nuclear-specific accumulation of fluorescence probe in BCa tumor cells was evaluated using laser scanning confocal microscopy (LSCM). Hematoxylin and eosin staining was performed to detect histopathological changes in the spleen, heart, liver, and kidney. RESULTS: The AO-(cRGDfK)2 probe did not cause a significant reduction in cell viability. LSCM analysis showed that AO-(cRGDfK)2 exhibited nuclear-specific ambulation in BCa cells and was not accumulated in 293T cells. Also, this probe efficiently targeted tumor cells in the serum and urine samples. In vivo imaging system of tumor-bearing mice showed that ~ 80% percent of fluorescence signal was accumulated in the tumor sites. The probe did not change histopathology in the heart, liver, spleen, and kidney in tumor-bearing mice after the 21-day treatment. CONCLUSIONS: The AO-(cRGDfK)2 probe exhibited nuclear-specific accumulation in BCa cells without cytotoxicity, which provides an innovative alternative to improve anticancer therapy for BCa.

Prediction of the Impact of CYP2C19 Polymorphism on Drug-Drug Interaction between Voriconazole and Tacrolimus Using Physiologically-Based Pharmacokinetic Modelling

Abstract Voriconazole increases tacrolimus blood concentration significantly when coadministrated. The recommendation of reducing tacrolimus to 1/3 in voriconazole package insert seems not to be satisfactory in clinical practice. In vitro studies demonstrated that the magnitude of inhibition depends on the concentration of voriconazole, while voriconazole exposure is determined by the genotype status of CYP2C19. CYP2C19 gene polymorphism challenges the management of drug-drug interactions(DDIs) between voriconazole and tacrolimus. This work aimed to predict the impact of CYP2C19 polymorphism on the DDIs by using physiologically based pharmacokinetics (PBPK) models. The precision of the developed voriconazole and tacrolimus models was reasonable by evaluating the pharmacokinetic parameters fold error, such as AUC0-24, Cmax and tmax. Voriconazole increased tacrolimus concentration immediately in all population. The simulated duration of DDIs disappearance after voriconazole withdrawal were 146h, 90h and 66h in poor metabolizers (PMs), intermediate metabolizers (IMs) and extensive metabolizers(EMs), respectively. The developed and optimized PBPK models in this study can be applied to assit the dose adjustment for tacrolimus with and without voriconazole.