Chemopreventive Effects of Pomegranate Seed Oil on Skin Tumor Development in CD₁ Mice

Abstract

Pomegranate seed oil was investigated for possible skin cancer chemopreventive efficacy in mice. In the main experiment, two groups consisting each of 30, 4-5-week-old, female CD(1) mice were used. Both groups had skin cancer initiated with an initial topical exposure of 7,12-dimethylbenzanthracene and with biweekly promotion using 12-O-tetradecanoylphorbol 13-acetate (TPA). The experimental group was pretreated with 5% pomegranate seed oil prior to each TPA application. Tumor incidence, the number of mice containing at least one tumor, was 100% and 93%, and multiplicity, the average number of tumors per mouse, was 20.8 and 16.3 per mouse after 20 weeks of promotion in the control and pomegranate seed oil-treated groups, respectively (P <.05). In a second experiment, two groups each consisting of three CD(1) mice were used to assess the effect of pomegranate seed oil on TPA-stimulated ornithine decarboxylase (ODC) activity, an important event in skin cancer promotion. Each group received a single topical application of TPA, with the experimental group receiving a topical treatment 1 h prior with 5% pomegranate seed oil. The mice were killed 5 h later, and ODC activity was assessed by radiometric method. The experimental group showed a 17% reduction in ODC activity. Pomegranate seed oil (5%) significantly decreased (P <.05) tumor incidence, multiplicity, and TPA-induced ODC activity. Overall, the results highlight the potential of pomegranate seed oil as a safe and effective chemopreventive agent against skin cancer.

In vitro antiproliferative, apoptotic and antioxidant activities of punicalagin, ellagic acid and a total pomegranate tannin extract are enhanced in combination with other polyphenols as found in pomegranate juice

“…Pomegranate juice and extracts have been shown to have potent in vitro antioxidant [7,24] and in vivo anti-atherosclerotic properties [8,9,15], attributed to its high content of polyphenols including ETs and EA. Recently, there have also been numerous reports on the in vitro and in vivo anticancer properties of pomegranates [10,[25][26][27][28][29][30]. The major pomegranate ET, punicalagin, is reported as the active ingredient responsible for N 50% of the juice's antioxidative potential [7,24] and can reach levels of N2 g/L of juice [7].…”

Pomegranate polyphenols down-regulate expression of androgen-synthesizing genes in human prostate cancer cells overexpressing the androgen receptor

“…Pomegranate polyphenols are potent antioxidants which have been shown both in vitro and in vivo to inhibit the growth of prostate and some other forms of cancer [10][11][12][13][14][15]. Our group has demonstrated that 8 ounces of pomegranate juice consumed daily following primary treatment of prostate cancer significantly prolonged prostate specific antigen (PSA) doubling time from 15 months to 54 months [30].…”

“…Sample RNA content was quantified by measuring the absorbance at 260 nm with a Gene Quant Spectrophotometer (Amersham-Pharmacia Biotech, Piscataway, NJ). Reverse transcription was performed on 3 μg of RNA by using oligo(dT) [12][13][14][15][16][17][18] primers (Invitrogen) with SuperScript III Reverse Transcriptase (Invitrogen) according to the manufacturer's instruction.…”

“…PA is the most abundant of these polyphenols and EA has been previously shown to exhibit anticarcinogenic properties such as induction of cell-cycle arrest and apoptosis, as well as the inhibition of tumor formation and growth in animals [7][8][9]. Pomegranate juice (PJ) consumption also has shown potent anticarcinogenic properties in various cancers [4,[10][11][12][13][14][15].…”

Atividade citotóxica e antiangiogênica de Punica granatum L., Punicaceae

“…Estudos na literatura estabeleceram a importância da atividade quimiopreventiva da P. granatum contra a incidência e a multiplicação tumoral (Kim et al, 2002;Hora et al, 2003).…”