Combined treatment with Epimedium koreanum Nakai extract and gefitinib overcomes drug resistance caused by T790M mutation in non-small cell lung cancer cells

Although the epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors, such as gefitinib, have shown promising therapeutic efficacy in nonsmall cell lung cancer (NSCLC) patients harboring EGFR activating mutation, development of acquired resistance is almost inevitable. We investigated whether the addition of Epimedium koreanum Nakai extract (EEF) to gefitinib could overcome the resistance of NSCLC cells to gefitinib. In our study, the growth inhibitory effects of cotreatment differed between mutant EGFR and wild type EGFR. A synergistic antiproliferative effect was observed in the combined treatments in H1975 and PC-9GR cells carrying T790M EGFR. In addition, the cotreatment exhibited a much greater inhibition than either agent alone on the following metastatic processes: (a) invasion, (b) wound healing, and (c) tubule formation by endothelial cells. The phosphorylations of EGFR family (EGFR, HER-2, and HER-3) and EGFR downstream PI3K/Akt/mTOR pathway in H1975 and PC-9/GR cells were also attanuated, whereas EEF or gefitinib alone had no obvious effects. Similarly, the combination effectively suppressed tumor growth and increased mice survival in PC-9GR xenografts. The results indicate that the addition of EEF to gefitinib is a promising strategy to overcome T790M-mediated drug resistance.

Effect of a derived herbal recipe from an ancient Chinese formula, Danggui Buxue Tang, on ovariectomized rats

ETHNOPHARMACOLOGICAL RELEVANCE

Radix Astragali (root of Astragalus membranaceus (Fisch.) Bge. var. mongholicus (Bge.) Hsiao, RA), Radix Angelicae sinensis (root of Angelica sinensis (Oliv.) Diels, RAS) and Folium Epimedii (leaves of Epimedium brevicomum Maxim., FE) are three of the extensively applied herbal remedies among traditional Chinese medicines for gynecological disorders and osteoporosis. A derivative herbal recipe-RRF, composed of the three medicines with a weight ratio of 5:1:5, is derived from a famous Chinese herbal formula-Danggui Buxue Tang (DBT). RRF has shown noteworthy protective effect in ovariectomized rats, which might represent a promising candidate for the treatment of perimenopausal disorders. The aim of this study was to investigate the herbal recipe RRF for its efficacy on perimenopausal disorders and the underlying mechanisms via ovariectomy (OVX) models.

MATERIALS AND METHODS

An experimental model of OVX female rats was applied. Vehicle (Sham and OVX group), RRF (564, 282 and 141 mg/kg/d) and conjugated equine estrogens (CEE, 0.1mg/kg/d, reference drug) were all administrated orally once daily for 16 weeks post operation. After the treatment, radioimmunoassay for estradiol (E(2)), lutenizing hormone (LH), follicle stimulating hormone (FSH) and β-endorphin (β--EP), neurotransmitter determination by high-performance liquid chromatography with electrochemical detector (HPLC-ECD) for norepinephrine (NE), dopamine (DA), 5-hydroxytryptamine (5-HT) and 5-HIAA (5-hydroxyindoleacetic acid), bone mineral density (BMD) assay as well as lipid peroxidation assessment, were carried out to probe into the effectiveness of RRF.

RESULTS

(1) RRF treatment enhanced E(2) synthese while diminished the elevated serum FSH and LH levels; in terms of neurotransmitter, β-EP syntheses rallied whereas the hypothalamic NE, DA and 5-HT release experienced varying mitigation in OVX female rats. (2) Repeated administration of RRF was able to attenuate osteoporosis by elevating the BMD levels of total body, and arrest the bone trabeculae degradation. (3) RRF exposure decreased serum levels of constituent MDA and increased endogenous SOD activity.

CONCLUSIONS

Results of the current studies revealed that RRF was capable of acting at multiple targets which presumably underlay its potential protective effect in OVX rats mimicking symptoms as observed in perimenopausal women. Hence, RRF might represent a promising candidate in the treatment of perimenopausal disorders in midlife women.

Reactive oxygen species-mediated mitochondrial pathway is involved in Baohuoside I-induced apoptosis in human non-small cell lung cancer

Baohuoside I (also known as Icariside II) is a flavonoid isolated from Epimedium koreanum Nakai. Although Baohuoside I exhibits anti-inflammatory and anti-cancer activities, its molecular targets/pathways in human lung cancer cells are poorly understood. Therefore, in the present study, we investigated the usefulness of Baohuoside I as a potential apoptosis-inducing cytotoxic agent using human adenocarcinoma alveolar basal epithelial A549 cells as in vitro model. The apoptosis induced by Baohuoside I in A549 cells was confirmed by annexin V/propidium iodide double staining, cell cycle analysis and dUTP nick end labeling. Further research revealed that Baohuoside I accelerated apoptosis through the mitochondrial apoptotic pathway, involving the increment of BAX/Bcl-2 ratio, dissipation of mitochondrial membrane potential, transposition of cytochrome c, caspase 3 and caspase 9 activation, degradation of poly (ADP-ribose) polymerase and the over-production of reactive oxygen species (ROS). A pan-caspase inhibitor, Z-VAD-FMK, only partially prevented apoptosis induced by Baohuoside I, while NAC, a scavenger of ROS, diminished its effect more potently. In addition, the apoptotic effect of Baohuoside I was dependent on the activation of ROS downstream effectors, JNK and p38(MAPK), which could be almost abrogated by using inhibitors SB203580 (an inhibitor of p38(MAPK)) and SP600125 (an inhibitor of JNK). These findings suggested that Baohuoside I might exert its cytotoxic effect via the ROS/MAPK pathway.