Cytotoxicity of sodium selenite in HaCaT cells induces cell death and alters the mRNA expression of PUMA,ATR, and mTOR genes

BackgroundBy identifying the molecular mechanisms underlying sodium selenite (Na₂SeO₃) cytotoxicity during exposure in non-tumor cells (HaCaT cells), we will improve the current understanding of its antiproliferative effects and modulation of gene expression in the main pathways related to the cell cycle, cell death, oxidative stress, and DNA damage and repair.MethodsNon-tumor HaCaT cells were treated with Na₂SeO₃ to induce cytotoxicity, and the effects were investigated using an MTT assay (cell viability), real-time cell analysis (profiling the cell index), flow cytometry (membrane integrity, cell cycle disruption, and apoptosis), a comet assay (genotoxicity, i.e., DNA damage), and RT-qPCR (mRNA expression of genes).ResultsTreatment with Na₂SeO₃ was cytotoxic at 10 μM, producing morphological changes in cells (cytoplasmic granulations); however, it did not have a genotoxic effect. Na₂SeO₃ induced cell membrane damage, cell death, and cell cycle arrest in HaCaT cells. It also altered the mRNA expression levels of PUMA, ATR, and mTOR genes. However, it had no effect on the mRNA expression of caspases or PARP1, BIRC5, BECN1, and c-MYC genes, suggesting that Na₂SeO₃ causes PUMA-dependent apoptosis in HaCaT cells. The mRNA expression of specific genes related to oxidative stress, DNA damage and repair, and cell cycle control were unchanged by Na₂SeO₃.ConclusionsWe demonstrated the cytotoxic effect of Na₂SeO₃ in HaCaT cells by analyzing mRNA expression patterns, changes in cell morphology, and proliferation kinetics.     

In vitro cytotoxic activity of extracts and isolated constituents of Salvia leriifolia Benth. against a panel of human cancer cell lines

In the course of recent efforts to identify new potential antiproliferative active principles, Salvia leriifolia extracts and isolated constituents were evaluated for their cytotoxic activity against a panel of human cancer cell lines, including renal adenocarcinoma (ACHN), amelanotic melanoma (C32), colorectal adenocarcinoma (Caco‐2), lung large cell carcinoma (COR‐L23), malignant melanoma (A375), lung carcinoma (A549), and hepatocellular carcinoma (Huh‐7D12) cells. The hexane and CH₂Cl₂ extracts showed the strongest cytotoxic activity against the C32 cell line with IC₅₀ values of 11.2 and 13.6 μg/ml, respectively, and the AcOEt extract was the most active extract against the COR‐L23 cell line (IC₅₀ of 20.9 μg/ml). Buchariol, a sesquiterpene obtained by biofractionation of the CH₂Cl₂ extract, exhibited a higher activity than the positive control vinblastine against the C32 and A549 cell lines (IC₅₀ values of 2.1 and 12.6 μM , resp.). Interesting results were also obtained for naringenin, a flavonoid isolated from the AcOEt extract, which exhibited a strong cytotoxic activity against the C32, LNCaP, and COR‐L23 cell lines (IC₅₀ values of 2.2, 7.7, and 33.4 μM , resp.), compared to vinblastine (IC₅₀ values of 3.3, 32.2, 50.0 μM , resp.). None of the tested compounds affected the proliferation of skin fibroblasts (142BR), suggesting a selective activity against tumor cells.     

New Functions for PI3K in the Control of Cell Division

Although cell lipids were initially envisioned as structural components of the cell, their essential contribution to initiation and regulation of cell responses is now clearly established. Among the different lipids that regulate cell responses, those produced by class I phosphoinositide 3-kinase (PI3K), phosphatidylinositol (3,4)P₂ (PIP₂), and phosphatidylinositol (3,4,5)P₃ (PIP₃), have concentrated much attention in recent years. PIP2 and PIP3 are involved in cell division and survival control, and mutations in the PI3K pathway are linked to autoimmunity and cancer. Here we discuss two novel observations: a PI3K function in the late-G₁ phase of the cell cycle and the contribution of the p85 PI3K regulatory subunit in the control of cytokinesis.     

Improving Efficiency of TiO<Subscript>2</Subscript>:Ag /Si Solar Cell Prepared by Pulsed Laser Deposition

Titanium dioxide (TiO₂) has been extensively studied and demonstrated to be suitable to enhance the efficiency of solar cell. In this work, TiO₂ is doped with silver nanoparticles (AgNP’s) on glass and the Si substrate by using Pulsed Laser Deposition (PLD) technique. UV–vis spectroscopy, X-ray diffraction (XRD), X-ray fluorescence (XRF), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Atomic Force Microscope (AFM), electrical conductivity (σ _dc), Hall coefficient (R_H), current–voltage (I–V), and capacity–voltage (C–V) characterizations have been used to examine the optical, the morphological, and the electrical properties of the films. It has been found that 5 wt.% (Ag) doped TiO₂ thin film has the most effect on efficiency of TiO₂:Ag /Si solar cell. The (I–V) characteristics showed that the (TiO₂) thin film enhances the efficiency of the (p–n) junction solar cell from 1.26 % pure TiO₂ to 7.19 % with doping of noble metal (Ag) representing improvement in the efficiency of solar cell leading to estimate empirical equations between efficiency, extinction coefficient, and energy band gap which have a total fit with the experimental data.     

Impact of oxidative stress on cellular biomechanics and rho signaling in C2C12 myoblasts

Although cells often can tolerate oxidative environments, abnormal oxidative stress has been identified in inflammation, cardiovascular and neurodegenerative diseases, and aging. The impact of oxidative stress on the cellular biomechanics is poorly understood, however. In this study, we used C2C12 myoblasts to investigate the effect of oxidative stress, mimicked by hydrogen peroxide (H₂O₂), on the cell elasticity (i.e., Young?s modulus), viability, and production of intracellular reactive oxygen species (ROS). To better understand the mechanisms underlying the impact of H₂O₂, we examined various effectors of the Rho signaling pathway, which has been shown to play a key role in the control of cell mechanics. H₂O₂ decreased the cell stiffness in a dose-dependent manner, caused cell death, and reduced the RhoA expression that was accompanied by down-regulation of α-actin, cytoskeleton-membrane linker proteins (ezrin–radixin–moesion proteins), and focal adhesion. Modulating the Rho signaling by using a Rho activator partially restored the cell stiffness, enhanced the cell viability, and decreased the intracellular ROS level, suggesting a potential intervention strategy to maintain the cellular biomechanical homeostasis and rescue cell damage in the threat of oxidative stresses.     

Monochloramine suppresses the proliferation of colorectal cancer cell line Caco‐2 by both apoptosis and G2/M cell cycle arrest

The aim of this study was to assess a possible role of monochloramine (NH₂Cl), one of the reactive chlorine species, which induce oxidative stress, on the proliferation of colorectal cancer cell line Caco‐2. At concentrations ranging from 10 to 200 μM, NH₂Cl (14–61% inhibition), but not hypochlorous acid, dose‐dependently inhibited the cell viability of Caco‐2 cells. Experiments utilizing methionine (a scavenger of NH₂Cl), taurine‐chloramine and glutamine‐chloramine revealed that only NH₂Cl affects the cancer cell proliferation among reactive chlorine species, with a relative specificity. Furthermore, flow‐cytometry experiments showed that the anti‐proliferative effect of NH₂Cl is partially attributable to both apoptosis and G2/M cell cycle arrest. These results suggest that NH₂Cl has the potential to suppress colorectal cancer cell proliferation. Copyright © 2013 John Wiley & Sons, Ltd.     

H2O2-Induced Cell Death in Human Glioma Cells: Role of Lipid Peroxidation and PARP Activation

underlying mechanism of ROS-induced cell injury remains to be defined. This study was undertaken to examine the role of lipid peroxidation and poly (ADP-ribose) polymerase (PARP) activation in H₂O₂-induced cell death in A172 cells, a human glioma cell line. H₂O₂ induced a dose- and time-dependent cell death. The cell death was prevented by thiols (dithiothreitol and glutathione), iron chelators (deferoxamine and phenanthroline), H₂O₂ scavengers (catalase and pyruvate), and a hydroxyl radical scavenger (dimethylthiourea). Antioxidants N,N-diphenyl-p-phenylenediamine (DPPD) and Trolox had no effect on the H₂O₂-induced cell death. Lipid peroxidation did not increase in human glioma cells exposed to H₂O₂. The PARP inhibitor 3-aminobenzamide prevented the cell death induced by H₂O₂. The PARP activity was increased by H₂O₂ and the H₂O₂ effect was prevented by 3-aminobenzamide, dithiothreitol, and phenanthroline. The ATP depletion induced by H₂O₂ was prevented by catalase, dithiothreitol, phenanthroline, and 3-aminobenzamide, but not by DPPD. These results indicate that the H₂O₂-induced cell death is mediated by PARP activation but not by lipid peroxidation in human glioma cells.     

Effects of Cell Density on Lipids of Human Glioma and Fetal Neural Cells

Abstract: Gangliosides, phospholipids, and cholesterol of human glioma (12-18) and fetal neural cells (CH) were analyzed at specified cell densities, from sparse to confluent. Total ganglioside sialic acid, phospholipid phosphorus, and cholesterol increased in the glioma cells on a per cell, mg protein, or mg total lipid basis two- to threefold as cell density increased 25-fold. These same three constituents in the fetal cells increased with cell density on a per cell and mg protein basis but not on a per mg total lipid basis. In glioma cells, the di- and trisialogangliosides (GD₂+ GD_lb+ GT₁) increased from 1–2% of total ganglioside sialic acid at sparse densities to 7–8% at intermediate (logarithmic phase) densities to 10–13% at confluent densities. The set of simpler gangliosides (GM₄+ GM₃+ GM₂) decreased from 50% of total ganglioside sialic acid at sparse glioma cell densities, to 36% at intermediate and 30% at confluent densities. In the fetal neural cells, the set of gangliosides (GM₄+ GM₃+ GM₂) had about 48% of total ganglioside sialic acid in both sparse and confluent preparations. The fetal cells were twofold higher in GM₃ (32.4 ± 2.1%) than the glioma cells (16.8 ± 1.6%), but lower in GM_t (9.1 ± 0.9% versus 18.2 ± 1.8%), cell densities notwithstanding. Confluent cell preparations of both cell lines were consistently higher in ethanolamine plasmalogen than sparse cells. We conclude that in these two neural cell lines quantitative changes in ganglioside and phospholipid species occurred correlatively as cell densities increased. Higher glioma cell densities were associated with greater proportions of complex ganglioside species. These changes in cell membrane constituents during growth may result from cell contact and may indicate a role for them in cell growth regulation and/or differentiation.     

Prostaglandin actions in established insect cell lines

Prostaglandins (PGs) are oxygenated metabolites of arachidonic acid (AA) and two other C20 polyunsaturated fatty acids that serve as biochemical signals mediating physiological functions. We reported that PGs influence protein expression in insect cell lines, which prompted the question: do PGs influence cell proliferation or viability in insect cell lines? Here, we report on the outcomes of experiments designed to address the question in cell lines from three insect orders: Hemiptera (squash bug, Anasa tristis, BCIRL-AtE-CLG15A), Coleoptera (red flour beetle, Tribolium castaneum, BCIRL-TcA-CLG1), and Lepidoptera (tobacco budworm, Heliothis virescens, BCIRL-HvAM1). Treating the insect cell lines with PGA₁, PGA₂, or PGD₂ led to dose-dependent reductions in cell numbers. All three cell lines were sensitive to PGA₁ and PGA₂ (IC₅₀s = 9.9 to 26.9 μM) and were less sensitive to PGD₂ (IC₅₀s = 31.6 to 104.7 μM). PG treatments also led to cell death at higher concentrations, as seen in mammalian cell lines. PGE₁, PGE₂, and PGF_2α treatments did not influence AtE-CLG15A or HvAM1 cell numbers at lower concentrations, but led to dose-related reductions in TcA-CLG1 cells at higher concentrations. Similar treatments with pharmaceutical inhibitors of PG biosynthesis also led to reduced cell numbers: MAFP (inhibits phospholipase A₂), indomethacin (inhibits PG biosynthesis), and esculetin (inhibits lipoxygenase). Because these pharmaceuticals are used to relieve inflammation and other medical issues in human medicine, they are not toxic to animal cells. We infer PGs are necessary in optimal quantities for ongoing homeostatic functions in established cell lines; in quantities outside the optimal concentrations, PGs are deleterious.     

p38α MAPK mediates 17β-estradiol inhibition of MMP-2 and -9 expression and cell migration in human lovo colon cancer cells

Epidemiological studies demonstrate that the incidence and mortality rates of colorectal cancer in women are lower than in men. However, it is unknown if 17β‐estradiol (E₂) treatment is sufficient to inhibit cell proliferation and cell migration in human colon cancer cells. Up‐regulation of urokinase plasminogen activator (uPA), tissue plasminogen activator (tPA), and matrix metallopeptidases (MMPs) is reported to associate with the development of cancer cell mobility, metastasis, and subsequent malignant tumor. In the present study, we treated human LoVo colon cancer cells with E₂ to explore whether E₂ down‐regulates cell proliferation and migration, and to identify the precise molecular and cellular mechanisms behind the down‐regulatory responses. Here, we found that E₂ treatment decreased cell proliferation and cell cycle‐regulating factors such as cyclin A, cyclin D1 and cyclin E. At the same time, E₂ significantly inhibited cell migration and migration‐related factors such as uPA, tPA, MMP‐2, and MMP‐9. However, E₂ treatment showed no effects on upregulating expression of plasminogen activator inhibitor‐1 (PAI‐1), tissue inhibitor of metalloproteinase‐1, ‐2, ‐3, and ‐4 (TIMP‐1, ‐2, ‐3, and ‐4). After administration of inhibitors including QNZ (NFκB inhibitor), LY294002 (Akt activation inhibitor), U0126 (ERK1/2 inhibitor), SB203580 (p38 MAPK inhibitor) or SP600125 (JNK1/2 inhibitor), E₂‐downregulated cell migration and expression of MMP‐2 and MMP‐9 in LoVo cells is markedly inhibited only by p38 MAPK inhibitors, SB203580. Application of specific target gene siRNA (ERα, ERβ, p38α, and p38β) to LoVo cells further confirmed that p38 MAPK mediates E₂/ERs inhibition of MMP‐2 and ‐9 expression and cell motility in LoVo cells. Collectively, these results suggest that E₂ treatment down‐regulates cell proliferation by modulating the expression of cyclin A, cyclin D1 and cyclin E. E₂ treatment simultaneously impaired cell migration by inhibiting the expression of uPA, tPA, MMP‐2, and MMP‐9 through E₂/ERs ? p38α MAPK signaling pathway in human LoVo colon cancer cells. J. Cell. Physiol. 227: 3648–3660, 2012. © 2012 Wiley Periodicals, Inc.     

The use of a human papillomavirus 18 promoter for tissue-specific expression in cervical carcinoma cells

The use of tissue-specific promoter elements in the treatment of cervical cancer has been explored in this paper. The P₁₀₅ promoter of human papillomavirus 18 (HPV18) was utilised to direct tissue-specific expression in a number of cell types. Expression was examined in three cervical carcinoma cell lines: HeLa (HPV18 positive), SiHa (HPV16 positive), and C33A cells (HPV negative); the epithelial cell line, H1299; and the foetal fibroblast cell line, MRC5, utilising a luciferase expression vector. Expression was highest in the cervical cell lines by a factor of at least 80. The effect of a number of mutations in the P₁₀₅ promoter on expression levels was examined. Three deletion constructs of the long control region (LCR) were investigated: an 800 bp fragment (LCR800), a 400 bp fragment (LCR400), and a 200 bp fragment (LCR200), as well as the full length product LCR of HPV18 (LCR1000). The LCR800 construct of the HPV18 P₁₀₅ promoter had the highest level of expression in the cervical cell lines and was also highest in the HPV18-positive HeLa cell line. Site-directed mutagenesis was then employed on the LCR800 construct to create four further constructs that each had inactivating mutations in one of the four E2 binding sites (E2BSs). Overall, this study indicated that the LCR800 construct of the HPV18 P₁₀₅ promoter could be utilised as a tissuerestricted promoter in cervical cancer cells.     

Toxicity of commercially available engineered nanoparticles to Caco-2 and SW480 human intestinal epithelial cells

The effects of ingestion of engineered nanoparticles (NPs), especially via drinking water, are unknown. Using NPs spiked into synthetic water and cell culture media, we investigated cell death, oxidative stress, and inflammatory effects of silver (Ag), titanium dioxide (TiO₂), and zinc oxide (ZnO) NPs on human intestinal Caco-2 and SW480 cells. ZnO NPs were cytotoxic to both cell lines, while Ag and TiO₂ NPs were toxic only at 100 mg/L to Caco-2 and SW480, respectively. ZnO NPs led to significant cell death in synthetic freshwaters with 1 % phosphate-buffered saline in both cell lines, while Ag and TiO₂ NPs in buffered water led to cell death in SW480 cells. NP exposures did not yield significant increased reactive oxygen species generation but all NP exposures led to increased IL-8 cytokine generation in both cell lines. These results indicate cell stress and cell death from NP exposures, with a varied response based on NP composition.     

An Evaluation of the Effects of Cytokines on Intracellular Oxidative Production in Normal Neutrophils by Flow Cytometry

To evaluate the effects of inflammatory cytokines on oxidative production in normal neutrophils, seven kinds of cytokines such as granulocyte-macrophage colony-stimulating factor (GM-CSF), granulocyte colonystimulating factor (G-CSF), interleukin-2 (IL-2), IL-6, IL-1α IL-1β, and interferon-β (IFN-β) were tested. The intracellular hydrogen peroxide (H₂O₂) in individual cells was determined by flow cytometry. According to the levels of intracellular H₂O₂ enhanced by cytokines, these seven cytokines were classified into three types: (1) prominently effective—GM-CSF; (2) moderately effective—G-CSF, IL-6, and IL-2; (3) weakly or ineffective—IFN-β, IL-1α, and IL-1β. Changes in cell size and cell surface structure after stimulation of those seven cytokines were simultaneously measured by flow cytometry. The most prominently effective cytokine, GM-CSF, initially caused enlargement of cell size and irregularity of the cell surface and subsequently increased H₂O₂ production by neutrophils. In contrast, the weakly or ineffective cytokines, like IL-1β, had no effects on cell size or cell surface. Our study indicates that some kinds of cytokines enhance oxidetive production and cause morphological changes in neutrophils.     

Post-irradiation DNA synthesis inhibition and G2 phase delay in radiosensitive body cells from non-Hodgkin's lymphoma patients: an indication of cell cycle defects

In the present study, both post-irradiation DNA synthesis and G₁ phase accumulation were analyzed in lymphoblastoid cell lines (LCLs) and fibroblast cell strains derived from (Saudi) patients with non-Hodgkin's lymphoma (NHL), ataxia telangiectasia (AT), AT heterozygotes and normal subjects. A comparison of the percent DNA synthesis inhibition (assayed by ³H-thymidine uptake 30 min after irradiation), and a 24 h post-irradiation G₂ phase accumulation determined by flow cytometry placed the AT heterozygotes and the NHL patients in an intermediate position between the normal subjects (with maximum DNA synthesis inhibition and minimum G₂ phase accumulation) and the AT homozygotes (with minimum DNA synthesis inhibition and maximum G₂ accumulation). The similarity between AT heterozygotes and the NHL patients with respect to the two parameters studied after irradiation was statistically significant. The data indicating a moderate abnormality in the control of cell cycle progression after irradiation in the LCLs and fibroblasts from NHL patients may explain the enhanced cellular and chromosomal radiosensitivity in these patients reported by us earlier. In addition to demonstrating a link between cell cyle abnormality and radiosensitivity as a possible basis for cancer susceptibility, particularly in the NHL patients, the present studies emphasized the usefulness of the assay for 24 h post-irradiation G₂ phase accumulation developed by Lavin et al. (1992) in characterizing AT heterozygote-like cell cycle anomally in cancer patients irrespective of whether they carried the AT gene or any other affecting the cell cycle.     

Development of a bovine luteal cell in vitro culture system suitable for co-culture with early embryos

The cross talk between the corpus luteum (CL) and the early embryo, potentially relevant to pregnancy establishment, is difficult to evaluate in the in vivo bovine model. In vitro co-culture of bovine luteal cells and early embryos (days?2?C8 post in vitro fertilization) may allow the deciphering of this poorly understood cross talk. However, early embryos and somatic cells require different in vitro culture conditions. The objective of this study was to develop a bovine luteal cell in vitro culture system suitable for co-culture with early embryos in order to evaluate their putative steroidogenic and prostanoid interactions. The corpora lutea of the different stages of the estrous cycle (early, mid, and late) were recovered postmortem and enriched luteal cell populations were obtained. In experiments 1 and 2, the effects of CL stage, culture medium (TCM, DMEM-F12, or SOF), serum concentration (5 or 10%), atmosphere oxygen tension (5 or 20%), and refreshment of the medium on the ability of luteal cells to produce progesterone (P₄) were evaluated. The production of P₄ was significantly increased in early CL cultures, and luteal cells adapted well to simple media (SOF), low serum concentrations (5%), and oxygen tensions (5%). In experiment 3, previous luteal cell cryopreservation did not affect the production of P₄, PGF_2??, and PGE₂ compared to fresh cell cultures. This enables the use of pools of frozen?Cthawed cells to decrease the variation in cell function associated with primary cell cultures. In experiment 4, mineral oil overlaying culture wells resulted in a 50-fold decrease of the P₄ quantified in the medium, but had no effect on PGF_2?? and PGE₂ quantification. In conclusion, a luteal cell in vitro culture system suitable for the 5-d-long co-culture with early embryos was developed.     

Effect of nitrogen deficiency on the ion-exchange properties of cell wall polymers from wheat roots

The ion-exchange properties of cell wall polymers isolated from the roots of wheat (Triticum aestivum L.) plants grown on either nitrate-free (N-deficient) or nitrate-containing (+N) hydroponic nutrient medium have been investigated. Irrespective of the nitrogen nutrition regimen, the studied cell walls contained four types of ion-exchange groups: primary amino groups of structural proteins (pK_a < 3), carboxyl groups of polygalacturonic acid in pectin (pK _a ~4.7), carboxyl groups of hydroxycinnamic acids (pK _a ~7.3), and phenolic OH-groups of lignin (pK_a ~10.2). The quantitative ratio between these types of ion-exchange groups, the mass fraction of cell walls in the dry weight of roots, and the swelling coefficient of cell walls depended on the nitrate presence in the growing medium. Compared to the +N variant, the N-deficient variant was characterized by a 2.4 times higher content of phenolic OH-groups in cell walls and 1.24 times higher mass fraction of cell walls; at the same time, the swelling coefficient for this variant was lower by 10%. The obtained data indicate that nitrogen deficiency results in a formation of thicker root cell walls with a higher degree of polymer cross-linking that may be caused by the increased lignin content.     

Effect of hepatocyte growth factor/scatter factor and other growth factors on motility and morphology of non-tumorigenic and tumor cells

Summary Using an automated cell analyzer system, the effect of hepatocyte growth factor/scatter factor (HGF/SF), epidermal growth factor (EGF), basic fibroblast growth factor (bFGF), endothelial acidic fibroblast growth factor (a-FGF), platelet derived growth factor (PDGF), and recombinant human insulinlike growth factor (IGF) on the motility and morphology of Madin-Darby canine kidney (MDCK), rat hepatomas, C₂, and H_5–6 and murine mammary carcinoma (EMT-6) cells was investigated. Treatment of MDCK cells with HGF/SF, bFGF, EGF, and a-FGF resulted in an increase in average cell velocity and in the fraction of moving cells. Cells treated with the PDGF and IGF did not show significant alterations in velocity. MDCK cells treated with each growth factor were classified into groups of “fast” and “slow” moving cells based on their average velocities, and the average morphologic features of the two groups were quantitated. Fast-moving cells had larger average area, circularity, and flatness as compared to slow-moving cells. Factors that stimulated cell movement also induced alterations in cell morphologic parameters including spreading, flatness, area, and circularity. HGF/SF also scattered and stimulated motility of C₂ and H_5–6 hepatoma cells. In contrast to MDCK cells, there was no significant difference between the morphology of the fast moving and slow moving C₂ and H_5–6 cells. These studies suggest that growth factor cytokines have specific effects on motility of normal and tumor cells.     

Anti-proliferative and apoptotic effects of oleuropein and hydroxytyrosol on human breast cancer MCF-7 cells

Olive oil intake has been shown to induce significant levels of apoptosis in various cancer cells. These anti-cancer properties are thought to be mediated by phenolic compounds present in olive. These beneficial health effects of olive have been attributed, at least in part, to the presence of oleuropein and hydroxytyrosol. In this study, oleuropein and hydroxytyrosol, major phenolic compound of olive oil, was studied for its effects on growth in MCF-7 human breast cancer cells using assays for proliferation (MTT assay), cell viability (Guava ViaCount assay), cell apoptosis, cellcycle (flow cytometry). Oleuropein or hydroxytyrosol decreased cell viability, inhibited cell proliferation, and induced cell apoptosis in MCF-7 cells. Result of MTT assay showed that 200 μg/mL of oleuropein or 50 μg/mL of hydroxytyrosol remarkably reduced cell viability of MCF-7 cells. Oleuropein or hydroxytyrosol decrease of the number of MCF-7 cells by inhibiting the rate of cell proliferation and inducing cell apoptosis. Also hydroxytyrosol and oleuropein exhibited statistically significant block of G₁ to S phase transition manifested by the increase of cell number in G₀/G₁ phase.     

Testosterone action on erythropoiesis does not require its aromatization to estrogen: Insights from the testosterone and estrogen treatment of two aromatase-deficient men

Androgens act on erythropoiesis, but the relative role of testosterone (T) and estradiol (E₂) on erythropoietic parameters in men is a poorly investigated issue. In order to evaluate separately the effects on erythropoiesis of high-dose T administration alone and of physiological dose of E₂ administration alone two adult men with aromatase deficiency were assessed before and during each treatment. Blood cell count, hemoglobin (Hb), hematocrit (Hct), erythrocyte mean cell volume (MCV), erythrocyte mean corpuscular hemoglobin (MCH), erythrocyte mean corpuscular hemoglobin concentration (MCHC), serum ferritin, iron and total iron-binding capacity (TIBC), serum erythropoietin, serum total testosterone and estradiol were evaluated. Hb, Hct and red cell count rose during testosterone treatment, consistently with the increase in circulating testosterone, but failed to increase during estradiol treatment. A decrease in Hb, Hct and red cell count was recorded in one of the two subjects during estradiol treatment, with a concomitant decrease in serum testosterone. Circulating T alone is capable of and sufficient to influence erythropoiesis, especially at supraphysiological dosage, while circulating E₂ have not the same effect on erythropoietic parameters, suggesting the hypothesis that the erythropoietic changes induced by androgens are not mediated via its aromatization to estrogens.