Abstract 830: Optimized retinoblastoma treatment approach using a Y79 retinoblastoma cellular model and CCK-8 in vitro assay protocol
Authors: Martinez Ashley M. Varela , Kim Hae Chan , Goli Naga , Campbell Robert 
Published: April 2023

Background: Retinoblastoma is one of the most common eye malignancies in children that develops in the retina. Repression of the disease is critical in retaining eyesight and reducing mortality. However, most chemotherapeutic agents cause unwanted side effects, often resulting from a lack of target specificity. Various drug delivery systems are being researched to overcome these adverse effects, some of which often utilize nanoparticles such as Cell Membrane Lipid-Extracted Nanoliposomes (CLENs). The objective of this study is to evaluate the selective cytotoxicity and cellular uptake of drug-loaded CLENs and CCK-8 in-vitro assay analysis.

Methods: The suspension cell line, Y79, was selected to study the selectivity of drug loaded CLENs in retinoblastoma. Y79 cells were seeded at 20,000 cells/mL of growth medium. Y79-CLENs included DOPC, and lipid extract (LE) derived from the Y79 cell line. Phase I of the experiment examined the cellular uptake activity of the CLENs in the Y79 varying the composition of DOPC/LE at a ratio of 90/10 or 80/20. DPPE-rhodamine label was included for fluorescence studies. The chemotherapeutic agent of choice for the study was doxorubicin hydrochloride (DOX). Phase II evaluated the cytotoxicity of DOX loaded in Y79-CLENs utilizing the CCK-8 in vitro assay. Multiple myeloma cell line (RPMI 8226) served as the control group for the investigation.

Results: The average mean diameter for preparations containing 0, 20, and 40 mol% Y79 lipid extract content was 143 ± 2 nm, 127 ± 12.7 nm, and 110 ± 4 nm, respectively. The corresponding zeta potential values for preparations containing 0, 20 and 40 mol% Y79-LE content was -13.43 ± 0.96 mV, -0.65 ± 2.86 mV, and -3.35 ± 1.79 mV, respectively. The zeta potential values for 0 and 20 mol% DOX-loaded Y79-CLENs were -5.51 ± 1.14 mV and -8.59 ± 0.98 mV, respectively. Y79-CLENs were taken up by Y79 cells to a greater extent when compared to the DOPC control preparations. Cellular uptake summary: ratio of DOPC/LE- 80/20 &gt; 90/10 &gt; 100/0. DOX-loaded Y79-CLEN liposomes demonstrated more selective cytotoxic drug effects against Y79 cells when compared with DOX-DOPC liposome controls using the CCK-8 in-vitro assay. The evaluation of cellular uptake and cytotoxicity of drug-loaded Y79-CLENs against cell populations is currently underway.

Conclusion: Preliminary studies suggest that Y79-CLENs have superior physicochemical characteristics and other beneficial features that collectively improve selectivity and cytotoxicity. Future studies involving the mechanism of uptake by target cells and in vivo activity are needed.

Citation Format: Ashley M. Varela Martinez, Hae Chan Kim, Naga Goli, Robert Campbell. Optimized retinoblastoma treatment approach using a Y79 retinoblastoma cellular model and CCK-8 in vitro assay protocol [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 830.