Liposomal-Naringenin Radiosensitizes Triple-Negative Breast Cancer MDA-MB-231 Cells In Vitro.

Background: Naringenin has shown great promise in the realm of cancer therapeutics, demonstrating excellent cytotoxic action toward cancer cells and the enhanced effects of radiation therapy in vitro. However, the medicinal value of naringenin is severely limited clinically by poor bioavailability. Thus, multiple drug-delivery strategies for overcoming this limitation have been developed, of which liposomes are considered the most suitable due to their amphiphilic, modifiable, and biocompatible characteristics. In this study, we investigated the role of naringenin and liposomal-delivered naringenin as adjuncts to radiotherapy in the MDA-MB-231 triple-negative breast cancer cell line in vitro. Materials and Methods: Liposomal-naringenin was synthesized by thin-film hydration and extrusion and was characterized by spectrophotometry, dynamic light scattering, and zeta potential. The effects of free-from naringenin and liposomal-naringenin were evaluated toward MDA-MB-231 cell viability when combined with varying doses of radiation. Additionally, cell growth patterns, morphology, and colony formation were evaluated. Results: The analysis demonstrated IC50 values of 387.5 and 546.6 µg/ml for naringenin and liposomal-naringenin, respectively. Naringenin and liposomal-naringenin significantly lowered cell viability, proliferation, and colony formation dose-dependently, as compared to radiation in isolation. Conclusion: The findings presented herein concur with previous accounts of the radiosensitizing potential of naringenin and further highlight the considerable biomedical application of liposomal-naringenin within the realm of radiotherapy.

An Automated Microscopic Scoring Method for the γ-H2AX Foci Assay in Human Peripheral Blood Lymphocytes.

Ionizing radiation is a potent inducer of DNA damage and a well-documented carcinogen. Biological dosimetry comprises the detection of biological effects induced by exposure to ionizing radiation to make an individual dose assessment. This is pertinent in the framework of radiation emergencies, where health assessments and planning of clinical treatment for exposed victims are critical. Since DNA double strand breaks (DSB) are considered to be the most lethal form of radiation-induced DNA damage, this protocol presents a method to detect DNA DSB in blood samples. The methodology is based on the detection of a fluorescent labelled phosphorylated DNA repair protein, namely, γ-H2AX. The use of an automated microscopy platform to score the number of γ-H2AX foci per cell allows a standardized analysis with a significant decrease in the turn-around time. Therefore, the γ-H2AX assay has the potential to be one of the fastest and sensitive assays for biological dosimetry. In this protocol, whole blood samples from healthy adult volunteers will be processed and irradiated in vitro in order to illustrate the usage of the automated and sensitive γ-H2AX foci assay for biodosimetry applications. An automated slide scanning system and analysis platform with an integrated fluorescence microscope is used, which allows the fast, automatic scoring of DNA DSB with a reduced degree of bias.