<i>Juglans regia</i> Hexane Extract Exerts Antitumor Effect, Apoptosis Induction and Cell Circle Arrest in Prostate Cancer Cells <i>In vitro</i>

Abstract

Purpose: To elucidate the anticancer activity of Juglans regia leaf extract and its effect on cell cycle analysis, apoptosis and cancer cell morphology.Methods: Hexane extract of the leaves of Juglans regia was prepared by hot extraction. The anticancer activity of Juglans regia extract against human prostate cancer (PC3) cells was evaluated by MTT assay. Flow cytometry, using propidium iodide as a staining agent, was used to study the effect of the extract on cell cycle phase distribution. Apoptosis induced by the extract was evaluated by Annexin V binding assay using flow cytometer. Alterations in cell morphology following apoptosis were studied by inverted phase contrast microscope.Results: The extract of Juglans regia exhibited a potent and dose-dependent anti-proliferative activity against human prostate cancer cells in vitro. The extract also induced significant apoptosis in these PC3 cancer cells as revealed by annexin V binding assay as well as inverted phase contrast microscopy. It triggered a significant formation of apoptotic bodies after treatment with varying concentrations of the extract. Within 48 h of incubation, approximately 9.5, 15.5 and 26.3 % of the cells underwent early apoptosis after treatment with 5, 50 and 100 μg/mL of the extract, respectively. Similarly, 5.2, 11.2 and 18.9 % of the cells underwent late apoptosis after treatment with 5, 50 and 100 μg/mL of the extract, respectively. Treatment with different concentrations of the extract for 48 h induced an increase in the population of cells in the sub-G1 phase and a slight decrease in the G2/M phase.Conclusion: The hexane extract of Juglans regia inhibits growth of human prostate cancer cells by inducing apoptosis with concomitant alterations in cell cycle phase distribution.Keywords: Prostate cancer, Juglans regia, Apoptosis, Flow cytometry, Cell cycle phase, Sub-G1 phase