Ability of Prenylflavanones Present in Hops to Induce Apoptosis in a Human Burkitt Lymphoma Cell Line

Abstract

The identification of effective cancer preventive compounds from hops has become an important issue in public health-related research. We compared the antiproliferative and apoptosis-inducing effects of side chain variants of prenylflavanones, e. g., 8-prenylnaringenin (7) and 8-geranylnaringenin (10), which have been identified in hops (Humulus lupulus), and their synthetic variations 8-furanmethylnaringenin (8) and 8-cinnamylnaringenin (9). These were accessible by a Mitsunobu reaction and Claisen rearrangement. Flavanones 9 and 10 showed cytotoxic and apoptotic activities. Apoptosis was induced in a mitochondrial dependent manner. 8-Cinnamylnaringenin (9) displayed noticeably improved apoptotic effects when compared to 8-prenylnaringenin. The potential of 8-prenylnaringenin (7) is shown in an ex vivo experiment on a multi-drug resistant leukaemia blast.

Abbreviations

Eu(Fod)₃:heptafluoro-7,7-dimethyloctanedionatoeuropium(III)

LDH:lactate dehydrogenase

PBS:phosphate-buffered saline

RPMI:Roswell Park Memorial Institute

Humulus lupulus - Cannabaceae - phyto-oestrogen - Burkitt lymphoma - apoptosis - mitochondrial permeability transition

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