Transport of a novel anti-cancer agent, fenretinide across Caco-2 monolayers

Abstract

Fenretinide is a synthetic retinoid with chemotherapeutic activity against various malignancies. Upon oral administration to animals, fenretinide was found to be incompletely absorbed and excreted primarily in feces. The purpose of this study was to determine the possible reasons for poor oral absorption of fenretinide using Caco-2 cell monolayers. To achieve this purpose, a solid dispersion of fenretinide with Povidone K25 was used. The apparent permeability coefficient (P(app)) of fenretinide across Caco-2 monolayers in the presence of bovine serum albumin (BSA) in the receiver was determined. Apical to basolateral (AP-BL) and basolateral to apical (BL-AP) flux studies were performed to determine the role of an efflux mechanism. In the presence of 4% BSA in the receiver, the P(app) was found to be (8.8 +/- 0.5) x 10(-8) cm/sec. The AP-BL flux increased linearly with an increase in fenretinide concentration (125-640 microM) in the presence of 4% BSA in the receiver. Efflux and paracellular pathways played an insignificant role in the permeability of fenretinide. A significant amount of drug, approximately 13-15% of the initial amount accumulated in the cell membrane. The amount of fenretinide in the donor decreased by 16% over a 3 h period. However, only 0.12% of the initial amount was found in the receiver. Also, the P(app) increased with an increase in plasma protein concentration in the receiver. On the basis of these results, the poor permeability of fenretinide can be attributed to its accumulation in the lipophilic cell membrane and poor partitioning into the receiver medium.

Preparation and in vitro evaluation of hydrophilic fenretinide nanoparticles

“…The amount of drug within the cell membrane, ranging from 11.07% ± 1.34% for B2 to 16.91% ± 2.78% for B1, is in agreement with the findings of Kokate et al who found 13-15% of the initial amount of fenretinide within the cell membrane [32]. While some studies report minimal loss due to the cell monolayer [40], our studies revealed a significant proportion of the drug associated with the cell monolayer both within the cells and associated with the lipid membrane.…”

“…The supernatant was removed (representing the drug content in the cell cytosol), stabilized with ethanol (20% sample, 80% ethanol), and allowed to incubate overnight. The pellet remaining in the centrifuge tube (representing the drug content in the cell membrane) was also incubated with 1.5 mLethanol overnight [32]. The filter, now devoid of cells, was additionally incubated overnight with 2.0 mL of ethanol.…”

Development and In Vitro-In Vivo Evaluation of Fenretinide-Loaded Oral Mucoadhesive Patches for Site-Specific Chemoprevention of Oral Cancer

“…As a result of these positive in vitro attributes, numerous oral cancer clinical trials have evaluated fenretinide (6,7). Complications such as low bioavailability and rapid drug elimination from the body (8,9), along with toxicity (e.g., mucositis and hyperlipidemia) (10,11), originating respectively after oral and intravenous administration, have impeded its use in chemoprevention for oral and other cancers.…”

Formulation and evaluation of biodegradable nanoparticles for the oral delivery of fenretinide

“…The drug concentration for the cell permeation study was selected based on information obtained from the literature about fenretinide experimental concentrations in Caco-2 cell models [27]. BSA in the receiver compartment was used to improve sink conditions and reduce non-specific binding [28].…”

“…The supernatant was removed (representing the drug content in the cell cytosol), stabilized with ethanol (20% sample, 80% ethanol), and allowed to incubate overnight. The pellet remaining in the centrifuge tube (representing the drug content in the cell membrane) was also incubated with 1.5 mL of ethanol overnight [27]. Additionally, the Transwell® filter, now devoid of cells, was incubated overnight with 2.0 mL of ethanol.…”