Avemar, a nontoxic fermented wheat germ extract, attenuates the growth of sensitive and 5-FdUrd/Ara-C cross-resistant H9 human lymphoma cells through induction of apoptosis

Avemar (MSC) is a nontoxic fermented wheat germ extract, which has been shown to significantly improve the survival rate in patients suffering from various malignancies. We investigated its effects in sensitive and 5-FdUrd/Ara-C cross-resistant H9 human lymphoma cells. After 48 and 72 h of incubation, Avemar inhibited the growth of sensitive H9 cells with IC50 values of 290 and 200 µg/ml, whereas the growth of 5-FdUrd/Ara-C cross-resistant H9 cells was attenuated with IC50 values of 180 and 145 µg/ml, respectively. Treatment with 300 µg/ml MSC for 48 h caused dose-dependent induction of apoptosis in 48% of sensitive H9 cells. In cross-resistant H9 cells, incubation with 200 µg/ml Avemar for 48 h led to 41% of apoptotic tumor cells. Growth arrest of sensitive H9 cells after exposure to various concentrations of MSC occurred mainly in the S phase of the cell cycle, thereby increasing the cell population from 54 to 73% while depleting cells in the G0-G1 phase from 40 to 19%. Growth arrest in cross-resistant H9 cells occurred also mainly in the S phase, increasing the cell population from 45 to 68% while depleting cells in the G0-G1 phase from 45 to 31%. As MSC treatment likely overcomes 5-FdUrd/Ara-C resistance, further investigations to elucidate the exact mechanisms are warranted. We conclude that Avemar exerts a number of beneficial effects which could support conventional chemotherapy of human malignancies

Pro- and anticarcinogenic mechanisms of piceatannol are activated dose dependently in MCF-7 breast cancer cells

Estrogenic procarcinogenic effects of piceatannol (PIC) contrast reports about anticarcinogenic activities of PIC. To explain this contradiction, we investigated PIC in estrogen-dependent MCF-7 breast cancer cells and elucidated those cellular mechanisms that correlated with the observed cell effects induced by PIC. Low PIC concentrations (50 nM) induced c-Myc that depended on progesterone receptor (PR) and estrogen receptor (ER). PR-mediated c-Myc induction by PIC was independent of nuclear PR activity but depended on mitogen-activated protein kinase (MAPK) signaling and was associated with an acceleration of cancer cell proliferation. In contrast, 25 mu M PIC inhibited deoxynucleotide triphosphate synthesis, activated Chk2 and p38-MAPK and this was accompanied by an attenuation of cancer cell growth. Apoptosis was most probably inhibited due to activation of Akt; however, high PIC concentrations (> 100 mu M) permitted apoptosis-like cell death in consequence to disruption of orchestrated mitotic signaling. The presented results show for the first time that nanomolar PIC concentrations signal through PR and Erk1/2 and provide a mechanistic explanation why moderate wine consumption-but not other alcoholic beverages-increases the breast cancer risk in women. In contrast, higher PIC concentrations in the micromolar range are considered for adjuvant anticancer therapeutic concepts

In vitro anti-neoplastic activity of the ethno-pharmaceutical plant Hypericum adenotrichum Spach endemic to western Turkey

Hypericum perforatum (St. John's wort) is well-established for its antidepressant activity throughout the world and also various other species within this genus are used in different folk medicines. Hyperforin of St. John's wort inhibited growth of cancer cell lines and the use of hypericin (another compound of H. perforatum) in cancer photodynamic therapy is proposed. Therefore, we investigated the anti-cancer properties of H. adenotrichum Spach (Guttiferae), an endemic species in Turkey called ‘kantaron’, which is used for wound healing and antiseptic effects. Freeze-dried plant was extracted with petroleum ether, dichloromethane, ethyl acetate, and methanol and the bioactivity of these extracts was analysed by proliferation assay, cell death determination, by investigating protein expression profiles specific for cell cycle arrest and apoptosis as well as composition by HPLC. The strongest anti-proliferative activity was determined for the petroleum ether extract with an IpC50 of H"5.8 µg/ml medium (referring to 1 mg dried plant) which correlated with cyclin D1 suppression and p21 induction. This extract also induced phosphorylation of H2AX, and activated caspase-3 followed by signature-type cleavage of PARP resulting in H"50% apoptosis at 23.2 µg/ml after 24 h of treatment. Neither hyperforin, hypericin, or amentoflavone contributed to these properties. To the best of our knowledge, we report for the first time that the endemic plant H. adenotrichum Spach exhibits potent p53-independent anti-neoplastic properties due to yet unexplored Hypericum constituents

Anti-leukaemic effects of two extract types of Lactuca sativa correlate with the activation of Chk2, induction of p21, downregulation of cyclin D1 and acetylation of alpha-tubulin

The water extract of the lettuce Lactuca sativa, but not the ethyl acetate extract, inhibited the growth of HL-60 leukaemia cells and MCF-7 breast cancer cells. This correlated with the activation of checkpoint kinase 2 (Chk2). the induction of the tumour suppressor p21, and the severe downregulation of the proto-oncogene cyclin D1. The ethyl acetate extract, but not the water extract, induced HL-60 cell death, which correlated With the aectylation of alpha-tubulin. The acetylation of alpha-tubulin is indicative for microtubuli stabilisation such as induced by taxol. The calculated amount for human intake would require approximately 3 kg lettuce to reach the required concentration shown to inhibit 50% HL-60 proliferation