Matrix metalloproteinase enzyme responsive delivery of 5-Fluorouracil using Collagen-I peptide functionalized Dendrimer-Gold nanocarrier.

OBJECTIVE: The aim was to develop matrix metalloproteinase 1 (MMP1) responsive nanoparticle system for the delivery of 5-fluorouracil (5Fu) anticancer drug. SIGNIFICANCE: The MMP1 in the cancer microenvironment-induced drug release have the advantage of targeted drug release and reduce the distribution of drug to the healthy tissues. METHOD: G5 poly(amidoamine) (PAMAM) dendrimer (G5)-coated gold nanoparticles (G5AuNP) were synthesized and loaded with 5Fu. The drug-loaded nanoparticles were further coated with collagen I (Col-I) peptide, which is a substrate for MMP1 enzyme (Col-I 5Fu@G5AuNP). RESULT: The nanoparticles were highly monodispersed with a particle size of 30 nm and showed high drug encapsulation efficiency. The release of drug from the nanoparticles in HEPES buffer pH 7.4 was faster, higher and better controlled when incubated with MMP1 enzyme. The half-maximum inhibitory concentration for Col-I 5Fu@G5AuNP was eight times lower than the 5Fu against MCF-7, suggesting the improved delivery and anticancer activity of 5Fu after encapsulation in the developed enzyme-responsive nanocarrier system. The computed tomography (CT) X-ray attenuation of Col-I@G5AuNP showed a good contrasting property. CONCLUSION: The formulation Col-I 5Fu@G5AuNP has improved anticancer activity than free drug and the CT imaging results are promising for its theranostic applications for breast cancer treatment.

A rare case: Antenatally diagnosed congenital high airway obstruction syndrome.

Congenital high airway obstruction syndrome (CHAOS) is a rare life-threatening fetal condition resulting from obstruction of the upper fetal airway which may be partial or complete. Prenatal diagnosis is crucial as it usually results in stillbirth or death after delivery if unrecognized. We report a case of CHAOS that was diagnosed prenatally due to characteristic ultrasound features. We also briefly review literature in light of current management options.