MicroRNA­155­5p inhibits trophoblast cell proliferation and invasion by disrupting centrosomal function.

Recurrent miscarriage is used to refer to more than three pregnancy failures before 20 weeks of gestation. Defective trophoblast cell growth and invasion are frequently observed in recurrent miscarriage. Several microRNAs (miRs), including miR­155­5p, are aberrantly upregulated in recurrent miscarriage; however, the underlying molecular mechanisms remain unclear. The centrosome orchestrates microtubule networks and coordinates cell cycle progression. In addition, it is a base for primary cilia, which are antenna­like organelles that coordinate signaling during development and growth. Thus, deficiencies in centrosomal functions can lead to several disease, such as breast cancer and microcephaly. In the present study, the signaling cascades were analyzed by western blotting, and the centrosome and primary cilia were observed and analyzed by immunofluorescence staining. The results showed that overexpression of miR­155­5p induced centrosome amplification and blocked primary cilia formation in trophoblast cells. Notably, centrosome amplification inhibited trophoblast cell growth by upregulating apoptotic cleaved­caspase 3 and cleaved­poly (ADP­ribose) polymerase in miR­155­5p­overexpressing trophoblast cells. In addition, overexpression of miR­155­5p inhibited primary cilia formation, thereby inhibiting epithelial­mesenchymal transition and trophoblast cell invasion. All phenotypes could be rescued when cells were co­transfected with the miR­155­5p inhibitor, thus supporting the role of miR­155­5p in centrosomal functions. It was also found that miR­155­5p activated autophagy, whereas disruption of autophagy via the depletion of autophagy­related 16­like 1 alleviated miR­155­5p­induced apoptosis and restored trophoblast cell invasion. In conclusion, the present study indicated a novel role of miR­55­5p in mediating centrosomal function in recurrent miscarriage.

Store-operated calcium entry inhibits primary ciliogenesis via the activation of Aurora A.

The primary cilium is an antenna-like organelle protruding from the cell surface that can detect physical and chemical stimuli in the extracellular space to activate specific signaling pathways and downstream gene expressions. Calcium ion (Ca2+ ) signaling regulates a wide spectrum of cellular processes, including fertilization, proliferation, differentiation, muscle contraction, migration, and death. This study investigated the effects of the regulation of cytosolic Ca2+ levels on ciliogenesis using chemical, genetic, and optogenetic approaches. We found that ionomycin-induced Ca2+ influx inhibited ciliogenesis and Ca2+ chelator BATPA-AM-induced Ca2+ depletion promoted ciliogenesis. In addition, store-operated Ca2+ entry and the endoplasmic reticulum Ca2+ sensor stromal interaction molecule 1 (STIM1) negatively regulated ciliogenesis. Moreover, an optogenetic platform was used to create different Ca2+ oscillation patterns by manipulating lighting parameters, including density, frequency, exposure time, and duration. Light-activated Ca2+ -translocating channelrhodopsin (CatCh) is activated by 470-nm blue light to induce Ca2+ influx. Our results show that high-frequency Ca2+ oscillations decrease ciliogenesis. Furthermore, the inhibition of cilia formation induced by Ca2+ may occur via the activation of Aurora kinase A. Cilia not only induce Ca2+ signaling but also regulate cilia formation by Ca2+ signaling.

Polo­like kinase 1 selective inhibitor BI2536 (dihydropteridinone) disrupts centrosome homeostasis via ATM­ERK cascade in adrenocortical carcinoma.

Adrenocortical carcinoma (ACC) is a rare but malignant tumor. Surgical removal, radiotherapy and combined chemotherapy are commonly used to treat ACC. Despite efforts for several decades, the mortality rate of ACC remains high after treatments. Therefore, identifying a novel therapeutic molecule is important to increase the survival rate of patients with ACC. The centrosome is a microtubule organizing center, and it also functions as a signaling hub to coordinate cell cycle progression. Deficiencies in the regulation of centrosome copy numbers may cause cell cycle arrest or even apoptosis. BI2536 is a polo like kinase 1­selective inhibitor and has been tested for the treatment of several types of cancer, including lung, oral and gastric cancer. However, to the best of our knowledge, its effects on ACC have not yet been examined. The present study revealed that BI2536 inhibited Y1 ACC cell proliferation in a time­ and dose­dependent manner. BI2536 blocked cell cycle progression and also induced cell apoptosis as shown by flow cytometry. Furthermore, following BI2536 treatment, centrosome amplification was induced, which resulted in aberrant mitosis. In terms of the mechanism, BI2536 induced DNA damage as evidenced by γH2AX staining and comet assay, followed by activation of ATM serine/threonine kinase­ERK signaling to promote centrosome amplification. Therefore, the present study suggested that BI2536 could be used as an adjuvant therapy in the treatment of ACC, and also revealed the underlying molecular mechanism.

Anti-Inflammatory and Anti-oxidative Effects of Puerarin in Postmenopausal Cardioprotection: Roles of Akt and Heme Oxygenase-1.

During menopause, the sharp decline in estrogen levels leads to an increased risk of cardiovascular disease in women. The inflammatory response and oxidative stress are reportedly involved in the development of cardiovascular disorders postmenopause. In this study, we evaluated the cardioprotective effects of puerarin, a phytoestrogen derived from the root of Pueraria lobate, and investigated its underlying molecular mechanisms. Puerarin alleviated cytotoxicity and the production of reactive oxygen species (ROS) in lipopolysaccharide (LPS)- and hydrogen peroxide-stimulated H9c2 cardiomyoblasts. Puerarin scavenges free radicals and reduces apoptosis, thereby suppressing NADPH oxidase-1 and Bax activation to attenuate the production of ROS and restore Bcl-2 expression. Additionally, puerarin inhibited the expression of inducible nitric oxide synthase, cyclooxygenase-2, and nitric oxide production and decreased the hypertrophic phenotype under LPS stimulation. Treatment with puerarin reduced the levels of malondialdehyde and restored glutathione levels when facing oxidative stress. Mechanistically, puerarin inhibited both the LPS-induced Toll-like receptor 4/NF-[Formula: see text]B and mitogen-activated protein kinase signaling pathways. Furthermore, it reversed both the LPS-mediated downregulation of Akt activation and heme oxygenase-1 (HO-1) expression. The cardioprotective effects of puerarin were abolished by inhibitors of Akt and HO-1 and the estrogen receptor antagonist fulvestrant (ICI). This indicated that the estrogen receptor mediated by these two molecules plays important roles in conferring the anti-inflammatory and anti-oxidative functions of puerarin. These results demonstrate the therapeutic potential of puerarin for treating heart disease in postmenopausal women through Akt and HO-1 activation.

PDGF-AA activates AKT and ERK signaling for testicular interstitial Leydig cell growth via primary cilia.

Testes control the development of male reproductive system. The testicular interstitial Leydig cells (Leydig cells) synthesize testosterone for promoting spermatogenesis and secondary sexual characteristics. Type A platelet-derived growth factor (PDGF-AA) is one of the most important growth factors in regulating Leydig cell growth and function. Knockout of PDGF-AA or its congenital receptor PDGFR-α leads to poor testicular development caused by reducing Leydig cell numbers, supporting PDGF-AA/PDGFR-α signaling regulates Leydig cell development. Primary cilium is a cellular antenna that functions as an integrative platform to transduce extracellular signaling for proper development and differentiation. Several receptors including PDGFR-α are observed on primary cilia for initiating signaling cascades in distinct cell types. Here we showed that PDGF-AA/PDGFR-α signaling promoted Leydig cells growth, migration, and invasion via primary cilia. Upon PDGF-AA treatment, AKT and ERK signaling were activated to regulate these cellular events. Interestingly, active AKT and ERK were detected around the base of primary cilia. Depletion of ciliary genes (IFT88 and CEP164) alleviated PDGF-AA-activated AKT and ERK, thus reducing Leydig cell growth, migration, and invasion. Thus, our study not only reveals the function of PDGF-AA/PDGFR-α signaling in maintaining testicular physiology but also uncovers the role of primary cilium and downstream signaling in regulating Leydig cell development.

ATM- and ATR-induced primary ciliogenesis promotes cisplatin resistance in pancreatic ductal adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers because of its late diagnosis and chemoresistance. Primary cilia, the cellular antennae, are observed in most human cells to maintain development and differentiation. Primary cilia are gradually lost during the progression of pancreatic cancer and are eventually absent in PDAC. Here, we showed that cisplatin-resistant PDAC regrew primary cilia. Additionally, genetic or pharmacological disruption of primary cilia sensitized PDAC to cisplatin treatment. Mechanistically, ataxia telangiectasia mutated (ATM) and ATM and RAD3-related (ATR), tumor suppressors that initiate DNA damage responses, promoted the excessive formation of centriolar satellites (EFoCS) and autophagy activation. Disruption of EFoCS and autophagy inhibited primary ciliogenesis, sensitizing PDAC cells to cisplatin treatment. Collectively, our findings revealed an unexpected interplay among the DNA damage response, primary cilia, and chemoresistance in PDAC and deciphered the molecular mechanism by which ATM/ATR-mediated EFoCS and autophagy cooperatively regulate primary ciliogenesis.

Etoposide Triggers Cellular Senescence by Inducing Multiple Centrosomes and Primary Cilia in Adrenocortical Tumor Cells.

Etoposide (ETO) has been used in treating adrenocortical tumor (ACT) cells. Our previous study showed that ETO inhibits ACT cell growth. In the present study, we show that ETO treatment at IC50 (10 µM) inhibited ACT cell growth by inducing cellular senescence rather than apoptosis. Several markers of cellular senescence, including enlarged nuclei, activated senescence-associated ß-galactosidase activity, elevated levels of p53 and p21, and down-regulation of Lamin B1, were observed. We further found that ETO induced multiple centrosomes. The inhibition of multiple centrosomes accomplished by treating cells with either roscovitine or centrinone or through the overexpression of NR5A1/SF-1 alleviated ETO-induced senescence, suggesting that ETO triggered senescence via multiple centrosomes. Primary cilia also played a role in ETO-induced senescence. In the mechanism, DNA-PK-Chk2 signaling was activated by ETO treatment; inhibition of this signaling cascade alleviated multiple ETO-induced centrosomes and primary cilia followed by reducing cellular senescence. In addition to DNA damage signaling, autophagy was also triggered by ETO treatment for centrosomal events and senescence. Importantly, the inactivation of DNA-PK-Chk2 signaling reduced ETO-triggered autophagy; however, the inhibition of autophagy did not affect DNA-PK-Chk2 activation. Thus, ETO activated the DNA-PK-Chk2 cascade to facilitate autophagy. The activated autophagy further induced multiple centrosomes and primary cilia followed by triggering senescence.

Genotoxic stress-activated DNA-PK-p53 cascade and autophagy cooperatively induce ciliogenesis to maintain the DNA damage response.

The DNA-PK maintains cell survival when DNA damage occurs. In addition, aberrant activation of the DNA-PK induces centrosome amplification, suggesting additional roles for this kinase. Here, we showed that the DNA-PK-p53 cascade induced primary cilia formation (ciliogenesis), thus maintaining the DNA damage response under genotoxic stress. Treatment with genotoxic drugs (etoposide, neocarzinostatin, hydroxyurea, or cisplatin) led to ciliogenesis in human retina (RPE1), trophoblast (HTR8), lung (A459), and mouse Leydig progenitor (TM3) cell lines. Upon genotoxic stress, several DNA damage signaling were activated, but only the DNA-PK-p53 cascade contributed to ciliogenesis, as pharmacological inhibition or genetic depletion of this pathway decreased genotoxic stress-induced ciliogenesis. Interestingly, in addition to localizing to the nucleus, activated DNA-PK localized to the base of the primary cilium (mother centriole) and daughter centriole. Genotoxic stress also induced autophagy. Inhibition of autophagy initiation or lysosomal degradation or depletion of ATG7 decreased genotoxic stress-induced ciliogenesis. Besides, inhibition of ciliogenesis by depletion of IFT88 or CEP164 attenuated the genotoxic stress-induced DNA damage response. Thus, our study uncovered the interplay among genotoxic stress, the primary cilium, and the DNA damage response.

Septin 7 is a centrosomal protein that ensures S phase entry and microtubule nucleation by maintaining the abundance of p150glued.

Septins play important roles in regulating development and differentiation. Septin 7 (SEPT7) is a crucial component in orchestrating the septin core complex into highly ordered filamentous structures. Here, we showed that genetic depletion of SEPT7 or treatment with forchlorfenuron (FCF; a compound known to affect septin filament assembly) led to reduced the S phase entry in cell models and zebrafish embryos. In addition to colocalizing with actin filaments, SEPT7 resided in the centrosome, and SEPT7 depletion led to aberrant mitotic spindle pole formation. This mitotic defect was rescued in SEPT7-deficient cells by wild-type SEPT7, suggesting that SEPT7 maintained mitotic spindle poles. In addition, we observed disorganized microtubule nucleation and reduced cell migration with SEPT7 depletion. Furthermore, SEPT7 formed a complex with and maintained the abundance of p150glued , the component of centriole subdistal appendages. Depletion of p150glued resulted in a phenotype reminiscent of SEPT7-deficient cells, and overexpression of p150glued reversed the defective phenotypes. Thus, SEPT7 is a centrosomal protein that maintains proper cell proliferation and microtubule array formation via maintaining the abundance of p150glued .

Clustering of Metabolic Risk Components and Associated Lifestyle Factors: A Nationwide Adolescent Study in Taiwan.

Clustering of metabolic syndrome (MetS) risk components in childhood has been linked to a higher risk of diabetes and cardiovascular diseases in adulthood. By using data from the 2010⁻2011 Nutrition and Health Survey in Taiwan, this study investigated epidemic patterns and correlates for the clustering of MetS risk components. A total of 1920 adolescents aged 12⁻18 years were included in this study. The MetS diagnostic criteria defined by the Taiwan Pediatric Association (TPA) and International Diabetes Federation (IDF) for adolescents and the criteria defined by the Joint Interim Statement for adults (JIS-Adult) were used to evaluate MetS and its abnormal components. The prevalence of TPA-, IDF-, and JIS-Adult-defined MetS was 4.1%, 3.0%, and 4.0%, with 22.1%, 19.3%, and 17.7%⁻18.1% of adolescents having high fasting glucose, low high-density lipoprotein cholesterol, and central obesity, respectively. A 0.4-to-0.5-fold decreased risk of having ≥2 MetS abnormal components was detected among adolescents who consumed ≥1 serving/week of dairy products and fresh fruits. Boys who consumed ≥7 drinks/week of soda and girls who consumed ≥7 drinks/week of tea had a 4.6- and 5.2-fold risk of MetS, respectively. In conclusion, our findings revealed significant dimensions of adolescent MetS, including detecting population-specific prevalent patterns for MetS risk components and their clustering, and emphasized on health promotion activities that reduce sugar-sweetened beverage intake.

Novel effect of Y-24180, a presumed specific platelet-activating factor receptor antagonist, on Ca2+ levels and growth of human osteosarcoma cells.

In human osteosarcoma MG63 cells, the effect of Y-24180, a presumed specific platelet-activating factor (PAF) receptor antagonist, on intracellular Ca(2+) concentration ([Ca(2+)](i)) and proliferation was measured by using fura-2 and tetrazolium as fluorescent dyes, respectively. Y-24180 (1-5 microM) caused a rapid and sustained [Ca(2+)](i) rise in a concentration-dependent manner. The [Ca(2+)](i) rise was inhibited by 35% by dihydropyridines or removal of extracellular Ca(2+), but was not altered by verapamil and diltiazem. In Ca(2+)-free medium, thapsigargin, an inhibitor of the endoplasmic reticulum Ca(2+)-ATPase, caused a monophasic [Ca(2+)](i) rise, after which 5 microM Y-24180 failed to increase [Ca(2+)](i); conversely, depletion of Ca(2+) stores with 5 microM Y-24180 abolished thapsigargin-induced [Ca(2+)](i) rise. U73122, an inhibitor of phoispholipase C, inhibited histamine-induced, but not 5 microM Y-24180-induced [Ca(2+)](i) rise. Overnight treatment with 0.1-5 microM Y-24180 inhibited cell proliferation in a concentration-dependent manner. Together, these findings suggest that Y-24180 acts as a potent and cytotoxic Ca(2+) mobilizer in human osteosarcoma cells, by inducing both extracellular Ca(2+) influx and intracellular Ca(2+) release. Alterations in cytosolic Ca(2+) regulation may lead to interferences of various cellular functions; thus, attention should be exercised in using Y-24180 as a selective PAF receptor antagonist.

Novel effect of Y-24180, a presumed specific platelet activation factor receptor antagonist, on Ca2+ levels and growth of human prostate cancer cells.

In human prostate cancer PC3 cells, the effect of Y-24180, a presumed specific platelet activation factor (PAF) receptor antagonist, on intracellular Ca2+ concentration ([Ca2+]i) was measured by using fura-2 as a Ca2+-sensitive fluorescent probe. Y-24180 (1-10 microM) caused a rapid and sustained [Ca2+]i rise in a concentration-dependent manner. The [Ca2+]i rise was prevented by 40% by removal of extracellular Ca2+, but was not changed by dihydropyridines, verapamil and diltiazem. In Ca2+-free medium, thapsigargin, an inhibitor of the endoplasmic reticulum Ca2+-ATPase, caused a monophasic [Ca2+]i rise, after which the increasing effect of 10 microM Y-24180 on [Ca2+]i was reduced by 67%; conversely, depletion of Ca2+ stores with 10 microM Y-24180 abolished thapsigargin-induced [Ca2+]i rise. U73122, an inhibitor of phospholipase C, inhibited ATP-, but not Y-24180-induced [Ca2+]i rise. Activation of protein kinase C with phorbol-12-myristate-13-acetate (PMA) enhanced Y-24180-induced [Ca2+]i rise by 70%. Overnight treatment with 0.1-10 microM Y-24180 inhibited cell proliferation in a concentration-dependent manner. Collectively, these results suggest that Y-24180 acts as a potent and cytotoxic Ca2+ mobilizer in prostate cancer cells, by stimulating both extracellular Ca2+ influx and intracellular Ca2+ release. Since alterations in Ca2+ movement may interfere with many cellular signalling processes unrelated to modulation of PAF receptors, caution must be applied in using this reagent as a selective PAF receptor antagonist.

Effect of Y-24180 on Ca2+ movement and proliferation in renal tubular cells.

In canine renal tubular cells, the effect of Y-24180, a presumed specific platelet activating factor (PAF) receptor antagonist, on intracellular Ca(2+) concentration ([Ca(2+)](i)) was measured by using fura-2 as a Ca(2+)-sensitive fluorescent probe. Y-24180 (0.1-10 microM) caused a rapid and sustained [Ca(2+)](i) rise in a concentration-dependent manner. The [Ca(2+)](i) rise was prevented by 30% by removal of extracellular Ca(2+), but was not changed by dihydropyridines, verapamil and diltiazem. Y-24180-induced Ca(2+) influx was confirmed by Mn(2+)-influx induced quench of fura-2 fluorescence. In Ca(2+)-free medium, thapsigargin, an inhibitor of the endoplasmic reticulum Ca(2+)-ATPase, caused a monophasic [Ca(2+)](i) rise, after which the increasing effect of 5 microM Y-24180 on [Ca(2+)](i) was abolished; conversely, depletion of Ca(2+) stores with 5 microM Y-24180 abolished thapsigargin-induced [Ca(2+)](i) rise. U73122, an inhibitor of phoispholipase C, inhibited ATP-, but not Y-24180-induced [Ca(2+)](i) rise. Overnight treatment with Y-24180 did not alter cell proliferation rate. Collectively, these results suggest that Y-24180 acts as a potent, but not cytotoxic, Ca(2+) mobilizer in renal tubular cells, by stimulating both extracellular Ca(2+) influx and intracellular Ca(2+) release. Since alterations in Ca(2+) movement may interfere many cellular signaling processes unrelated to modulation of PAF receptors, caution must be applied in using this chemical as a selective PAF receptor antagonist.

Reducing dust using the electrocautery pencil with suction combined with the infusion catheter in mastectomy.

The dust from the vaporized tissue released during a mastectomy presents a hazard to the patients and the operating room personnel. More dust has been noted using the conventional electrocautery pencil in dissecting breast tissue than with the metal knife used in the past. It is very important to reduce the hazardous dust released during mastectomy. For this study 80 patients undergoing mastectomy for breast cancer from March to June 2001 were divided into two groups: 1) those whose dissections were performed with a combination of an electrocautery pencil and suction with an intravenous infusion catheter (40 cases) and 2) those whose dissections were performed with the conventional method in which the electrocautery pencil was handled by the surgeon and the metal suction tube was used separately by an assistant (40 cases). During mastectomy the personal air sampler was affixed to the operator's neck to collect the dust from the vaporized tissue. The concentrations of the total dust were significantly lower in the combined electrocautery-suction method (mean 5.56 +/- 3.26 microg/m3) than in the conventional method (mean 34.81 +/- 4.83 microg/m3) during mastectomy (P < 0.05). Although the operating time and blood loss were less in the combined method than in the conventional method this difference was not statistically significant (P > 0.05). The combined method of using the electrocautery pencil for dissecting breast tissue along with the intravenous infusion catheter reduced the concentrations of the total dust from the vaporized tissue plume. Furthermore this method reduces the hazards of dust to the surgeons and operating room personnel. Additionally the cost of this combined method is lower than that of the conventional method.

Novel action of lignans isolated from Hernandia nymphaeifolia on Ca(2+) signaling in renal tubular cells.

The effect of five lignans, epi-aschantin, epi-magnolin, epi-yangambin, deoxypodophyllotoxin and yatein, isolated from Hernandia nymphaeifolia on Ca(2+) signaling in Madin-Darby canine kidney cells was examined using fura-2 as a Ca(2+) indicator. These lignans at concentrations between 10 and 100 microM increased [Ca(2+)](i) in a concentration-dependent manner. Removal of extracellular Ca(2+) abolished the Ca(2+) signals evoked by 50 microM of the lignans. La(3+)(50 microM) abolished the Ca(2+) signals induced by 100 microM of epi-aschantin, epi-magnolin and epi-yangambin, and 20 microM deoxypodophyllotoxin, but inhibited by 60% 50 microM yatein-induced responses. All five lignans (50-100 microM) inhibited by 42-65% thapsigargin-induced capacitative Ca(2+) entry, and inhibited by 23-61% thapsigargin-induced intracellular Ca(2+) release. Epi-yangambin (100 microM), epi-magnolin (100 microM), and epi-aschantin (100 microM) inhibited by 8-38% 10 microM ATP-induced Ca(2+) release. Trypan blue exclusion revealed that incubation with deoxypodophyllotoxin or yatein (but not the other lignans) decreased cell viability in a concentration-dependent manner. Together, the results suggest that, in renal tubular cells, these lignans exert multiple actions on Ca(2+) signaling. They caused Ca(2+) influx but reduced thapsigargin-induced capacitative Ca(2+) entry and also thapsigargin- and ATP-induced Ca(2+) release. Additionally, deoxypodophyllotoxin and yatein may be cytotoxic.

Effect of lignans isolated from Hernandia nymphaeifolia on estrogenic compounds-induced calcium mobilization in human neutrophils.

The effect of five lignans isolated from Hernandia nymphaeifolia on estrogenic compounds (17beta-estradiol, tamoxifen and clomiphene)-induced Ca(2+) mobilization in human neutrophils was investigated. The five lignans were epi-yangambin, epi-magnolin, epi-aschantin, deoxypodophyllotoxin and yatein. In Ca(2+)-containing medium, the lignans (50-100 microM) inhibited 10 microM 17beta-estradiol- and 5 microM tamoxifen-induced increases in intracellular free Ca(2+) levels ([Ca(2+)](i)) without changing 25 microM clomiphene-induced [Ca(2+)](i) increase. 17beta-estradiol and tamoxifen increased [Ca(2+)](i) by causing Ca(2+) influx and Ca(2+) release because their responses were partly reduced by removing extracellular Ca(2+). In contrast, clomiphene solely induced Ca(2+) release. The effect of the lignans on these two Ca(2+) movement pathways underlying 17beta-estradiol- and tamoxifen-induced [Ca(2+)](i) increases was explored. All the lignans (50-100 microM) inhibited 10 microM 17beta-estradiol-and 5 microM tamoxifen-induced Ca(2+) release, and 17beta-estradiol-induced Ca(2+) influx. However, only 100 microM epi-aschantin was able to reduce tamoxifen-induced Ca(2+) influx while the other lignans had no effect. Collectively, this study shows that the lignans altered estrogenic compounds-induced Ca(2+) signaling in human neutrophils in a multiple manner.