A novel cancer preventative botanical mixture, TriCurin, inhibits viral transcripts and the growth of W12 cervical cells harbouring extrachromosomal or integrated HPV16 DNA.

BACKGROUND: The phytochemical mixture TriCurin (curcumin, epigallocatechin gallate (EGCG) and resveratrol) eliminates human papillomavirus (HPV) (+) cancer cells in vitro and in vivo. In this study, we further evaluate TriCurin. METHODS: The activity of TriCurin and its individual compounds was assayed on W12 cells, derived from a cervical precancer containing episomal and integrated HPV16 DNA, using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assays, microscopy and reverse transcription-polymerase chain reaction (RT-PCR), and on HeLa cells by gene expression analysis. The stability and toxicity of TriCurin microemulsion were tested in an organotypic cervical tissue model. RESULTS: TriCurin and its individual compounds inhibit the growth of W12 cells, episomal, type 1 and 2 integrants; the relative order of activity is TriCurin, EGCG, curcumin, or resveratrol. RT-PCR shows that TriCurin activates p53 and suppresses HPV16 mRNAs E1, E2, E4, E6 and E7 at 24 h in W12 cells. Gene expression analysis shows that TriCurin activates pro-apoptotic genes and represses anti-apoptotic genes in HeLa cells. TriCurin in a microemulsion is stable and non-toxic to cervical tissue. The combination of TriCurin and tanshinone IIA exhibits additional synergy against HeLa cells. CONCLUSIONS: TriCurin, and the combination of TriCurin with tanshinone IIA, are effective against HPV (+) cells. The phytochemical mixture, in the microemulsion-based cream, is a promising therapeutic for the prevention and treatment of cervical cancer.

A transcriptomic analysis of black cohosh: Actein alters cholesterol biosynthesis pathways and synergizes with simvastatin.

Previous studies indicate that the herb black cohosh (Actaea racemosa L.) and the triterpene glycoside actein inhibit the growth of human breast cancer cells and activate stress-associated responses. This study assessed the transcriptomic effects of black cohosh and actein on rat liver tissue, using Ingenuity and ToxFX analyses. Sprague-Dawley rats were treated with an extract of black cohosh enriched in triterpene glycosides (27%) for 24 h or actein for 6 and 24 h, at 35.7 mg/kg, and liver tissue collected for gene expression analysis. Ingenuity analysis indicates the top canonical pathways are, for black cohosh, RAR Activation, and, for actein, Superpathway of Cholesterol Biosynthesis, at 24 h. Actein alters the expression of cholesterol biosynthetic genes, but does not inhibit HMG-CoA reductase activity. Black cohosh and actein inhibited the growth of human breast and colon cancer cells and synergized with the statin simvastatin. Combinations of black cohosh with certain classes of statins could enhance their activity, as well as toxic, such as inflammatory liver, side effects. Transcriptomic analysis indicates black cohosh and actein warrant further study to prevent and treat cancer and lipid disorders. This study lays the basis for an approach to characterize the mode of action and toxicity of herbal medicines.

A transcriptomic analysis of turmeric: Curcumin represses the expression of cholesterol biosynthetic genes and synergizes with simvastatin.

The spice turmeric (Curcuma longa L.) has a long history of use as an anti-inflammatory agent. The active component curcumin induces a variety of diverse biological effects and forms a series of degradation and metabolic products in vivo. Our hypothesis is that the field of toxicogenomics provides tools that can be used to characterize the mode of action and toxicity of turmeric components and to predict turmeric-drug interactions. Male Sprague-Dawley rats were treated for 4 days with turmeric root containing about 3% curcumin (comparable to what people consume in the fresh or dried root) or a fraction of turmeric enriched for curcumin (∼74%) and liver tissue collected for gene expression analysis. Two doses of each agent were added to the diet, corresponding to 540 and 2700 mg/kg body weight/day of turmeric. The transcriptomic effects of turmeric on rat liver tissue were examined using 3 programs, ToxFx Analysis Suite, in the context of a large drug database, Ingenuity Pathway and NextBio analyses. ToxFx analysis indicates that turmeric containing about 3% or 74% curcumin represses the expression of cholesterol biosynthetic genes. The dose of 400 mg/kg b.w./day curcumin induced the Drug Signature associated with hepatic inflammatory infiltrate. Ingenuity analysis confirmed that all 4 turmeric treatments had a significant effect on cholesterol biosynthesis, specifically the Cholesterol biosynthesis superpathway and Cholesterol biosynthesis 1 and 2. Among the top 10 up or downregulated genes, all 4 treatments downregulated PDK4; while 3 treatments downregulated ANGPTL4 or FASN. These findings suggest curcumin may enhance the anticancer effects of certain classes of statins, which we confirmed with biological assays. Given this enhancement, lower levels of statins may be required, and even be desirable. Our findings also warn of possible safety issues, such as potential inflammatory liver effects, for patients who ingest a combination of certain classes of statins and curcumin. Transcriptomic analysis suggests that turmeric is worthwhile to study to prevent and treat cancer and lipid disorders. Our approach lays new groundwork for studies of the mode of action and safety of herbal medicines and can also be used to develop a methodology to standardize herbal medicines.

Digitoxin enhances the growth inhibitory effects of thapsigargin and simvastatin on ER negative human breast cancer cells.

BACKGROUND: The cardiac glycoside digitoxin preferentially inhibits the growth of breast cancer cells and targets the Erk pathway. Digitoxin alters the expression of genes that mediate calcium metabolism and IAP genes. PURPOSE: Since the optimal treatment for cancer involves the use of agents in combination, we assessed the growth inhibitory effects of digitoxin combined with agents that alter calcium metabolism, thapsigargin, a sarcoplasmic/ER Ca(2+)-ATPase inhibitor, and the statin simvastatin, as well as digitoxin's effect on the IAP pathway of apoptosis. METHODS: To reveal signaling pathways, we treated human cancer cells with digitoxin, alone or combined with thapsigargin or simvastatin, and measured cell growth using the MTT and colony formation assays. We used histology and Western blot analysis of HEK293 cells to assay effects on IAPs. RESULTS: Digitoxin inhibited the growth of breast, colon and ovarian cancer cells. Consistent with an effect on calcium metabolism, digitoxin exhibited synergy with thapsigargin and simvastatin on ER-negative breast cancer cells. Digitoxin activates expression of Erk pathway genes and suppresses expression of IAP genes. The growth inhibitory effects on HEK293 cells are not blocked by the pancaspase inhibitor zVAD-FMK, indicating that digitoxin may act by a caspase independent pathway of apoptosis. Furthermore, digitoxin does not have an effect on XIAP protein, a major anti-apoptotic protein. CONCLUSION: Digitoxin appears to act through the Erk and stress response pathways and is worthwhile to study to prevent and treat cancer. Our findings warn of possible safety issues for cardiac patients who take a combination of digitoxin and statins.

Histone H3.3 and its proteolytically processed form drive a cellular senescence programme.

The process of cellular senescence generates a repressive chromatin environment, however, the role of histone variants and histone proteolytic cleavage in senescence remains unclear. Here, using models of oncogene-induced and replicative senescence, we report novel histone H3 tail cleavage events mediated by the protease Cathepsin L. We find that cleaved forms of H3 are nucleosomal and the histone variant H3.3 is the preferred cleaved form of H3. Ectopic expression of H3.3 and its cleavage product (H3.3cs1), which lacks the first 21 amino acids of the H3 tail, is sufficient to induce senescence. Further, H3.3cs1 chromatin incorporation is mediated by the HUCA histone chaperone complex. Genome-wide transcriptional profiling revealed that H3.3cs1 facilitates transcriptional silencing of cell cycle regulators including RB/E2F target genes, likely via the permanent removal of H3K4me3. Collectively, our study identifies histone H3.3 and its proteolytically processed forms as key regulators of cellular senescence.

Mitogen-activated protein kinase signaling mediates phosphorylation of polycomb ortholog Cbx7.

Cbx7 is one of five mammalian orthologs of the Drosophila Polycomb. Cbx7 recognizes methylated lysine residues on the histone H3 tail and contributes to gene silencing in the context of the Polycomb repressive complex 1 (PRC1). However, our knowledge of Cbx7 post-translational modifications remains limited. Through combined biochemical and mass spectrometry approaches, we report a novel phosphorylation site on mouse Cbx7 at residue Thr-118 (Cbx7T118ph), near the highly conserved Polycomb box. The generation of a site-specific antibody to Cbx7T118ph demonstrates that Cbx7 is phosphorylated via MAPK signaling. Furthermore, we find Cbx7T118 phosphorylation in murine mammary carcinoma cells, which can be blocked by MEK inhibitors. Upon EGF stimulation, Cbx7 interacts robustly with other members of PRC1. To test the role of Cbx7T118 phosphorylation in gene silencing, we employed a RAS-induced senescence model system. We demonstrate that Cbx7T118 phosphorylation moderately enhances repression of its target gene p16. In summary, we have identified and characterized a novel MAPK-mediated phosphorylation site on Cbx7 and propose that mitogen signaling to the chromatin template regulates PRC1 function.

Actein induces calcium release in human breast cancer cells.

BACKGROUND: The triterpene glycoside actein from the herb black cohosh preferentially inhibits the growth of breast cancer cells and activates the ER stress response. The ER IP3 receptor and Na,K-ATPase form a signaling microdomain. Since actein is lipophilic, its action may be limited by bioavailability. PURPOSE: To develop actein to prevent and treat cancer, we examined the primary targets and combinations with chemotherapy agents, as well as the ability of nanoparticles to enhance the activity. MATERIALS AND METHODS: To reveal signaling pathways, we treated human breast and colon cancer, as well as 293T and 293T (NF-κB), cells with actein, and measured effects using the MTT, luciferase promoter, Western blot and histology assays. To assess effects on calcium release, we preloaded cells with the calcium sensitive dye Fura-2. To enhance bioavailability, we conjugated actein to nanoparticle liposomes. RESULTS: Actein strongly inhibited the growth of human breast cancer cells and induced a dose dependent release of calcium into the cytoplasm. The ER IP3 receptor antagonist heparin blocked this release, indicating that the receptor is required for activity. Heparin partially blocked the growth inhibitory effect, while the MEK inhibitor U0126 enhanced it. Consistent with this, actein synergized with the ER mobilizer thapsigargin. Further, actein preferentially inhibited the growth of 293T (NF-κB) cells. Nanoparticle liposomes increased the growth inhibitory activity of actein. CONCLUSIONS: Actein alters the activity of the ER IP3 receptor and Na,K-ATPase, induces calcium release and modulates the NF-κB and MEK pathways and may be worthwhile to explore to prevent and treat breast cancer.

Carnosic acid inhibits the growth of ER-negative human breast cancer cells and synergizes with curcumin.

BACKGROUND: Studies indicate that extracts and purified components, including carnosic acid, from the herb rosemary display significant growth inhibitory activity on a variety of cancers. PURPOSE: This paper examines the ability of rosemary/carnosic acid to inhibit the growth of human breast cancer cells and to synergize with curcumin. MATERIALS AND METHODS: To do this, we treated human breast cancer cells with rosemary/carnosic acid and assessed effects on cell proliferation, cell cycle distribution, gene expression patterns, activity of the purified Na/K ATPase and combinations with curcumin. RESULTS: Rosemary/carnosic acid potently inhibits proliferation of ER-negative human breast cancer cells and induces G1 cell cycle arrest. Further, carnosic acid is selective for MCF7 cells transfected for Her2, indicating that Her2 may function in its action. To reveal primary effects, we treated ER-negative breast cancer cells with carnosic acid for 6h. At a low dose, 5 µg/ml (15 µM), carnosic acid activated the expression of 3 genes, induced through the presence of antioxidant response elements, including genes involved in glutathione biosynthesis (CYP4F3, GCLC) and transport (SLC7A11). At a higher dose, 20 µg/ml, carnosic acid activated the expression of antioxidant (AKR1C2, TNXRD1, HMOX1) and apoptosis (GDF15, PHLDA1, DDIT3) genes and suppressed the expression of inhibitor of transcription (ID3) and cell cycle (CDKN2C) genes. Carnosic acid exhibits synergy with turmeric/curcumin. These compounds inhibited the activity of the purified Na-K-ATPase which may contribute to this synergy. CONCLUSION: Rosemary/carnosic acid, alone or combined with curcumin, may be useful to prevent and treat ER-negative breast cancer.

MicroRNA regulation of Cbx7 mediates a switch of Polycomb orthologs during ESC differentiation.

The Polycomb Group (PcG) of chromatin modifiers regulates pluripotency and differentiation. Mammalian genomes encode multiple homologs of the Polycomb repressive complex 1 (PRC1) components, including five orthologs of the Drosophila Polycomb protein (Cbx2, Cbx4, Cbx6, Cbx7, and Cbx8). We have identified Cbx7 as the primary Polycomb ortholog of PRC1 complexes in embryonic stem cells (ESCs). The expression of Cbx7 is downregulated during ESC differentiation, preceding the upregulation of Cbx2, Cbx4, and Cbx8, which are directly repressed by Cbx7. Ectopic expression of Cbx7 inhibits differentiation and X chromosome inactivation and enhances ESC self-renewal. Conversely, Cbx7 knockdown induces differentiation and derepresses lineage-specific markers. In a functional screen, we identified the miR-125 and miR-181 families as regulators of Cbx7 that are induced during ESC differentiation. Ectopic expression of these miRNAs accelerates ESC differentiation via regulation of Cbx7. These observations establish a critical role for Cbx7 and its regulatory miRNAs in determining pluripotency.

Chemopreventive potential of black cohosh on breast cancer in Sprague-Dawley rats.

BACKGROUND/AIM: This study examines the chemopreventive potential and action of the herb black cohosh on Sprague-Dawley rats. MATERIALS AND METHODS: Female Sprague-Dawley rats were treated with an extract of black cohosh enriched in triterpene glycosides (27%) at 35.7 (Group I), 7.14 (Group II), 0.714 (Group III) or 0 mg/kg b.w. for 40 weeks starting from 56 weeks of age and the incidence of benign and malignant mammary tumors was determined at the end of observation. RESULTS: Among female rats treated at 35.7 and 7.14 mg/kg b.w. there was a dose-related reduction (p<0.05) of the incidence of mammary adenocarcinomas when compared to the treatment of 0.714 mg/kg b.w., with a protection index (calculated relative to the group III; PI=[total tumours × 100 animals of group III] - [total tumours × 100 animals of the group I (or group II)]/ [total tumours of group III] × 100) for mammary adenocarcinomas of 87.5 and 48.8%, respectively. Black cohosh reduced Ki-67 and cyclin D1 protein expression in fibroadenomas, by immunohistochemistry. CONCLUSION: Our results suggest that black cohosh may have chemopreventive potential for mammary cancer.

Pharmacological mechanisms of black cohosh in Sprague-Dawley rats.

BACKGROUND: Studies indicate that extracts and purified components from black cohosh inhibit the growth of human breast cancer cells, but the molecular targets and signaling pathways have not yet been defined. PURPOSE: This study examines the pharmacological mechanisms and toxicological effects in the short term of the herb black cohosh on female Sprague-Dawley rats. MATERIALS AND METHODS: To assess effects on gene activity and lipid content, we treated female Sprague-Dawley rats with an extract of black cohosh enriched in triterpene glycosides (27%) at 35.7 or 0mg/kg. Four animals for each group were sacrificed at 1, 6 and 24h after treatment; liver tissue and serum samples were obtained for gene expression and lipid analysis. RESULTS: Microarray analysis of rat liver tissue indicated that black cohosh markedly downregulated mitochondrial oxidative phosphorylation genes. Phospholipid biosynthesis and remodeling, PI3-Kinase and sphingosine signaling were upregulated, driven largely by an upregulation of several isoforms of phospholipase C. Hierarchical clustering indicated that black cohosh clustered with antiproliferative compounds, specifically tubulin binding vinca alkaloids and DNA alkylators. In support of this, black cohosh repressed the expression of cyclin D1 and ID3, and inhibited the proliferation of HepG2, p53 positive, liver cancer cells. Black cohosh reduced the level of free fatty acids at 6 and 24h and triglycerides at 6h in the serum, but increased the free fatty acid and triglyceride content of the treated livers at 24h. CONCLUSION: Our results suggest that black cohosh warrants further study for breast cancer prevention and therapy.

Digitoxin activates EGR1 and synergizes with paclitaxel on human breast cancer cells.

BACKGROUND: Numerous studies have suggested that digitalis derivatives promise to be superior to existing adjuvant therapy for breast cancer as to effects and side-effects. In the present study, we have used gene expression analysis to determine the molecular action of digitoxin on breast cancer cells and assessed digitoxin's ability to synergize with the chemotherapy agent paclitaxel with respect to inhibition of cell proliferation MATERIALS AND METHODS: We treated (Her2 overexpressing, ER low) MDA-MB-453 human breast cancer cells with digitoxin at four doses {20 ng/ml (26 nM) to 1 µg/ml} and collected RNA at 6 h and 24 h for gene expression analysis. To examine the effects on ER positive cells, we treated MCF7 cells with digitoxin at 1 µg/ml and collected RNA for RT-PCR analysis. In addition, we assayed the growth inhibitory effect of low doses of digitoxin combined with paclitaxel and determined combination index values. RESULTS: To reveal primary effects, we examined digitoxin's effect 6 h post-treatment with the highest dose, 1µg/ml, and found upregulation of the stress response genes EGR-1 and NAB2, lipid biosynthetic genes and the tumor suppressor gene p21, and downregulation of the mitotic cell cycle gene CDC16 and the replication gene PolR3B. RT-PCR analysis validated effects on stress response, apoptotic and cell cycle genes on MDA-MB-453 and MCF7 cells. Western blot analysis confirmed induction of EGR1 protein at 1 h and ATF3 at 24 h. Paclitaxel, as well as digitoxin, inhibited the in vitro activity of the purified Na(+)-K(+)-ATPase; digitoxin enhanced the growth inhibitory effects of paclitaxel on Her2 overexpressing breast cancer cells. CONCLUSIONS: Our studies show the potential of digitoxin to prevent and treat breast cancer and indicate that the combination of digitoxin and paclitaxel is a promising treatment for ER negative breast cancer. These findings are the first to alert physicians to the possible dangers to patients who take a combination of digitoxin and paclitaxel. The potential dangers ensuing when paclitaxel and digitoxin are combined are dependent on the dose of digitoxin.

Actein activates stress- and statin-associated responses and is bioavailable in Sprague-Dawley rats.

The purpose of this study was to assess in rats the pharmacological parameters and effects on gene expression in the liver of the triterpene glycoside actein. Actein, an active component from the herb black cohosh, has been shown to inhibit the proliferation of human breast cancer cells. To conduct our assessment, we determined the molecular effects of actein on livers from Sprague-Dawley rats treated with actein at 35.7 mg/kg for 6 and 24 h. Chemogenomic analyses indicated that actein elicited stress and statin-associated responses in the liver; actein altered expression of cholesterol and fatty acid biosynthetic genes, p53 pathway genes, CCND1 and ID3. Real-time RT-PCR validated that actein induced three time-dependent patterns of gene expression in the liver: (i) a decrease followed by a significant increase of HMGCS1, HMGCR, HSD17B7, NQO1, S100A9; (ii) a progressive increase of BZRP and CYP7A1 and (iii) a significant increase followed by a decrease of CCND1 and ID3. Consistent with actein's statin- and stress-associated responses, actein reduced free fatty acid and cholesterol content in the liver by 0.6-fold at 24 h and inhibited the growth of human HepG2 liver cancer cells. To determine the bioavailability of actein, we collected serum samples for pharmacokinetic analysis at various times up to 24 h. The serum level of actein peaked at 2.4 microg/mL at 6 h. Actein's ability to alter pathways involved in lipid disorders and carcinogenesis may make it a new agent for preventing and treating these major disorders.

Partners in imprinting: noncoding RNA and polycomb group proteins.

Establishment of genomic imprints during early development involves concerted epigenetic mechanisms. Two recent studies by Terranova et al. (in this issue of Developmental Cell) and Pandey et al. (in a recent issue of Molecular Cell) have demonstrated that Polycomb group proteins (PcG) and the Kcnq1ot1 regulatory RNA, respectively, are indispensable for gene- and lineage-specific chromatin modification and compaction of the paternally imprinted Kcnq1 cluster.

Actein inhibits the Na+-K+-ATPase and enhances the growth inhibitory effect of digitoxin on human breast cancer cells.

The Na+K+-ATPase is a known target of cardiac glycosides such as digitoxin and ouabain. We determined that the enzyme also is a target of the structurally-related triterpene glycoside actein, present in the herb black cohosh. Actein's inhibition of Na+-K+-ATPase activity was less potent than that of digitoxin, but actein potentiated digitoxin's inhibitory effect on Na+-K+-ATPase activity and MDA-MB-453 breast cancer cell growth. We observed different degrees of signal amplification for the two compounds. Actein's inhibitory effect on ATPase activity was amplified 2-fold for cell growth inhibition, whereas digitoxin's signal was amplified 20-fold. Actein induced a biphasic response in proteins downstream of ATPase: low dose and short duration of treatment upregulated NF-kappaB promoter activity, p-ERK, p-Akt and cyclin D1 protein levels, whereas higher doses and longer exposure inhibited these activities. Actein and digitoxin may be a useful synergistic combination for cancer chemoprevention and/or therapy.

Growth inhibitory activity of extracts and compounds from Cimicifuga species on human breast cancer cells.

The purpose of this report is to explore the growth inhibitory effect of extracts and compounds from black cohosh and related Cimicifuga species on human breast cancer cells and to determine the nature of the active components. Black cohosh fractions enriched for triterpene glycosides and purified components from black cohosh and related Asian species were tested for growth inhibition of the ER(-) Her2 overexpressing human breast cancer cell line MDA-MB-453. Growth inhibitory activity was assayed using the Coulter Counter, MTT and colony formation assays. Results suggested that the growth inhibitory activity of black cohosh extracts appears to be related to their triterpene glycoside composition. The most potent Cimicifuga component tested was 25-acetyl-7,8-didehydrocimigenol 3-O-beta-d-xylopyranoside, which has an acetyl group at position C-25. It had an IC(50) of 3.2microg/ml (5microM) compared to 7.2microg/ml (12.1microM) for the parent compound 7,8-didehydrocimigenol 3-O-beta-d-xylopyranoside. Thus, the acetyl group at position C-25 enhances growth inhibitory activity. The purified triterpene glycoside actein (beta-d-xylopyranoside), with an IC(50) equal to 5.7microg/ml (8.4microM), exhibited activity comparable to cimigenol 3-O-beta-d-xyloside. MCF7 (ER(+)Her2 low) cells transfected for Her2 are more sensitive than the parental MCF7 cells to the growth inhibitory effects of actein from black cohosh, indicating that Her2 plays a role in the action of actein. The effect of actein on Her2 overexpressing MDA-MB-453 and MCF7 (ER(+)Her2 low) human breast cancer cells was examined by fluorescent microscopy. Treatment with actein altered the distribution of actin filaments and induced apoptosis in these cells. These findings, coupled with our previous evidence that treatment with the triterpene glycoside actein induced a stress response and apoptosis in human breast cancer cells, suggest that compounds from Cimicifuga species may be useful in the prevention and treatment of human breast cancer.

The growth inhibitory effect of actein on human breast cancer cells is associated with activation of stress response pathways.

Previous studies indicate that the triterpene glycoside actein from the herb black cohosh inhibits growth of human breast cancer cells. This study seeks to identify genes altered in human breast cancer cells by treatment with actein, using gene expression analysis. We treated MDA-MB-453 human breast cancer cells with actein at 2 doses, 20 or 40 microg/mL, for 6 or 24 hr. We identified 5 genes that were activated after each of the treatments that are known to play a role in cellular responses to diverse stresses, including the DNA damage and unfolded protein responses. In addition, four genes that mediate the integrated stress response (ISR), including activating transcription factor 4, were induced under at least one of the 4 treatment conditions. We used hierarchical clustering to define clusters comprising patterns of gene expression. Two ISR genes, activating transcription factor 3 (ATF3) and DNA damage- inducible transcript 3, and lipid biosynthetic genes were activated after exposure to actein at 40 microg/mL for 6 hr, whereas the cell cycle genes cyclin E2 and cell division cycle 25A were repressed. Our results suggest that actein induces 2 phases of the ISR, the survival phase and the apoptotic phase, depending on the dose and duration of treatment. We confirmed the results of gene expression analysis with real-time RT-PCR for 18 selected genes and Western blot analysis for ATF3. Since actein activated transcription factors that enhance apoptosis, and repressed cell cycle genes, it may be useful in the prevention and therapy of breast cancer.

Gene expression analysis of the mechanisms whereby black cohosh inhibits human breast cancer cell growth.

BACKGROUND: Previous studies indicate that specific extracts and the pure triterpene glycoside actein obtained from black cohosh inhibit growth of human breast cancer cells. Our aim is to identify alterations in gene expression induced by treatment with a methanolic extract (MeOH) of black cohosh. MATERIALS AND METHODS: We treated MDA-MB-453 human breast cancer cells with the MeOH extract at 40 microg/ml and collected RNA at 6 and 24 h; we confirmed the microarray results with real-time RT-PCR for 18 genes. RESULTS: At 6 h after treatment there was significant increase in expression of ER stress (GRP78), apoptotic (GDF15), lipid biosynthetic (INSIG1 and HSD17B7) and Phase 1 (CYP1A1) genes and, at 24 h, decrease in expression of cell cycle (HELLS and PLK4) genes. CONCLUSION: Since the MeOH extract activated genes that enhance apoptosis and repressed cell cycle genes, it may be useful in the prevention and therapy of breast cancer.

Rapid differentiation between short-chain-length and medium-chain-length polyhydroxyalkanoate-accumulating bacteria with spectrofluorometry.

An approach for rapid differentiation between short-chain-length (scl) and medium-chain-length (mcl) polyhydroxyalkanoate (PHA) producers was developed. Polyhydroxyalkanoate-accumulated bacterial cells stained with Nile red were suspended in water and subjected to fluorescence spectroscopy at a fixed excitation wavelength of 488 nm. The scl-PHA-accumulated bacteria revealed a maximum emission wavelength at 590 nm, and for mcl-PHA producers were seen at a wavelength of 575 nm. Combining Nile red staining and fluorescence spectroscopy, the accumulated PHA granules could be rapidly differentiated into scl-PHA and mcl-PHA from the intact cells.