bluuebunny/crossref_metadata_2025_split huggingface dataset:
Immunohistochemical detection of tyrosine phosphatase SHP‐1 predicts outcome after radical prostatectomy for localized prostate cancer
Authors: Tassidis Helena , Brokken Leon J.S. , Jirström Karin , Ehrnström Roy , Pontén Fredrik , Ulmert David , Bjartell Anders , Härkönen Pirkko , Wingren Anette Gjörloff 
Published: September 2009

AbstractThe protein tyrosine kinase (PTK) receptors and cytosolic signaling proteins as well as the protein tyrosine phosphatases (PTPs) have important roles in regulation of growth of the benign and malignant prostate gland. Here, we studied expression of the protein tyrosine phosphatase SHP‐1 in prostate cancer cell lines and in human prostatic tissues. SHP‐1 is expressed at a high level in LNCaP prostate cancer cells compared with PC3 cells. Silencing of SHP‐1 expression with siRNA in LNCaP cells led to an increased rate of proliferation, whereas overexpression of SHP‐1 by means of transient and stable transfection in PC3 cells led to a decrease in proliferation. Corresponding changes were observed in cyclin D1 expression. We further demonstrate that LNCaP and PC3 cells respond differently to IL‐6 stimulation. SHP‐1 overexpression in PC3 cells reversed IL‐6 stimulation of proliferation, whereas in SHP‐1‐silenced LNCaP cells, IL‐6 inhibition of proliferation was not affected. In addition, IL‐6 treatment led to higher levels of phosphorylated STAT3 in SHP‐1‐silenced LNCaP cells than in control cells. Next, SHP‐1 expression in human prostate cancer was analyzed by immunohistochemical staining of tissue microarrays comprising tumor specimens from 100 prostate cancer patients. We found an inverse correlation between the tumor level of SHP‐1 expression and time to biochemical recurrence and clinical progression among prostate cancer patients. In conclusion, our results suggest that a decreased level of SHP‐1 expression in prostate cancer cells is associated with a high proliferation rate and an increased risk of recurrence or clinical progression after radical prostatectomy for localized prostate cancer.
Evidence for tissue factor phosphorylation and its correlation with protease‐activated receptor expression and the prognosis of primary breast cancer
Authors: Rydén Lisa , Grabau Dorthe , Schaffner Florence , Jönsson Per‐Ebbe , Ruf Wolfram , Belting Mattias 
Published: September 2009

AbstractTissue factor (TF)‐mediated protease‐activated receptor (PAR)‐2 signaling is associated with a promigratory, invasive and proangiogenic phenotype in experimental models of breast cancer and has been mechanistically coupled to phosphorylation of the TF cytoplasmic domain (pTF). However, the clinical relevance of these findings is unknown. Here, we provide the first in vivo evidence of TF phosphorylation in experimental as well as clinical breast cancer tumors. pTF was demonstrated in MDA‐MB‐231 xenografts and in tumors from the MMTV‐PyMT transgene model of spontaneous murine breast adenocarcinoma. Tumors from PAR‐2–deficient transgenic mice were negative for pTF, thus linking pTF to PAR‐2 signaling. The clinical correlation between TF, pTF, PAR‐1, PAR‐2 and vascular endothelial growth factor (VEGF)‐A was determined by immunohistochemistry on tumors from a cohort of 172 consecutive primary breast cancer patients, with a median follow‐up time of 50 months. In 160 evaluable patient tumors, pTF was associated with TF (p = 0.01) and cancer cell expression of PAR‐1 (p = 0.001), PAR‐2 (p = 0.014) and VEGF‐A (p = 0.003) using χ2 test. PAR‐2 and VEGF‐A were coexpressed (p = 0.013) and associated with a more aggressive phenotype. Interestingly, all patients experiencing recurrences had tumors expressing pTF and PAR‐2, and pTF alone as well as coexpression of pTF and PAR‐2 were significantly correlated with shorter recurrence‐free survival (log rank test, p = 0.04 and p = 0.02, respectively). This study provides the first evidence to link PAR‐2 expression and TF phosphorylation to clinical data in human breast cancer. In conjunction with experimental tumor models, these data support an important role of TF‐PAR‐2 signaling in breast cancer recurrence.
Unifying roles for regulatory T cells and inflammation in cancer
Authors: Erdman Susan E. , Rao Varada P. , Olipitz Werner , Taylor Christie L. , Jackson Erin A. , Levkovich Tatiana , Lee Chung‐Wei , Horwitz Bruce H. , Fox James G. , Ge Zhongming , Poutahidis Theofilos 
Published: September 2009

AbstractActivities of CD4+ regulatory (TREG) cells restore immune homeostasis during chronic inflammatory disorders. Roles for TREG cells in inflammation‐associated cancers, however, are paradoxical. It is widely believed that TREG function in cancer mainly to suppress protective anticancer responses. However, we demonstrate here that TREG cells also function to reduce cancer risk throughout the body by efficiently downregulating inflammation arising from the gastrointestinal (GI) tract. Building on a “hygiene hypothesis” model in which GI infections lead to changes in TREG that reduce immune‐mediated diseases, here we show that gut bacteria‐triggered TREG may function to inhibit cancer even in extraintestinal sites. Ability of bacteria‐stimulated TREG to suppress cancer depends on interleukin (IL)‐10, which serves to maintain immune homeostasis within bowel and support a protective antiinflammatory TREG phenotype. However, under proinflammatory conditions, TREG may fail to provide antiinflammatory protection and instead contribute to a T helper (Th)‐17‐driven procarcinogenic process; a cancer state that is reversible by downregulation of inflammation. Consequently, hygienic individuals with a weakened IL‐10 and TREG‐mediated inhibitory loop are highly susceptible to the carcinogenic consequences of elevated IL‐6 and IL‐17 and show more frequent inflammation‐associated cancers. Taken together, these data unify seemingly divergent disease processes such as autoimmunity and cancer and help explain the paradox of TREG and inflammation in cancer. Enhancing protective TREG functions may promote healthful longevity and significantly reduce risk of cancer.
Regulation of REDD1 by insulin‐like growth factor‐I in skeletal muscle and myotubes
Authors: Frost Robert A. , Huber Danuta , Pruznak Anne , Lang Charles H. 
Published: September 2009

AbstractInsulin‐like growth factor‐I (IGF‐I) is a major anabolic hormone for skeletal muscle and a potent stimulus for protein synthesis and translation initiation. Recent studies suggest that translation can be inhibited by over expression of the mammalian target of rapamycin (mTOR) repressor REDD1. The purpose of the present study was to determine whether IGF‐I alters the expression of REDD1 and whether this is associated with a concomitant change in protein synthesis in vitro. Subcutaneous injection of IGF‐I or intravenous delivery of insulin for 3–4 h increased REDD1 mRNA in skeletal muscle 7–10‐fold. A threefold increase in REDD1 was observed when C2C12 myotubes were treated with IGF‐I. REDD1 protein continued to be expressed for up to 24 h after addition of IGF‐I to cells. Withdrawal of IGF‐I from myotubes lead to a rapid loss of REDD1 protein content. IGF‐I‐induced REDD1 mRNA and protein expression were prevented by inhibitors of transcription and translation. IGF‐I had an additive effect with dexamethasone (Dex) on REDD1 protein content in myotubes. The PI3K inhibitor LY294002 blocked IGF‐I but not Dex induced REDD1. IGF‐I also stimulated REDD1 promoter activity. Although REDD1 protein was elevated 5–6 h after addition of IGF‐I to myotubes, protein synthesis measured during this 1 h window was paradoxically greater in myotubes expressing more REDD1. In contrast to the IGF‐I induced increase in REDD1 mRNA, REDD2 mRNA was decreased by IGF‐I. We conclude that IGF‐I stimulates REDD1 expression in skeletal muscle and myotubes but under these conditions the REDD1 response is not sufficient to repress protein synthesis. J. Cell. Biochem. 108: 1192–1202, 2009. © 2009 Wiley‐Liss, Inc.
Altered protein‐expressing profile in hPNAS4‐induced apoptosis in A549 human lung adenocarcinoma cells
Authors: Gou Lan‐Tu , Tong Ai‐Ping , Yan Fei , Yuan Zhu , He Fei , Wang Wei , Zhou Yan , Chen Li‐Juan , Tang Ming‐Hai , Yang Jin‐Liang 
Published: September 2009

AbstractHuman PNAS4 (hPNAS4) is a recently identified pro‐apoptosis gene, which is able to induce apoptosis in A549 human lung adenocarcinoma cells following its overexpression. In this work, we investigated the changes of protein profile in hPNAS4‐induced apoptosis in A549 cells through proteomic strategy consisting of two‐dimensional electrophoresis (2‐DE) coupled with MALDI‐Q‐TOF mass spectrometry. A total of 20 different proteins with more than 3.0‐fold change in expression, including 5 up‐regulated and 15 down‐regulated proteins were successfully identified by database search. The mRNA transcription levels of the different proteins were further examined by RT‐PCT. Functional analyses showed these different proteins are involved in diverse biological processes including metabolism, proteolysis, signal transduction, apoptosis, and redox regulation. Two essential apoptosis‐associated protein, annexin A1 and prothymosin alpha, were confirmed by Western blot and showed consistent changes with proteomic detection. Our data provide molecular evidence and possible associated pathway in hPNAS4‐induced apoptosis through proteomic strategy, which should be contributed to further investigation on biological function of hPNAS4. J. Cell. Biochem. 108: 1211–1219, 2009. © 2009 Wiley‐Liss, Inc.
Geometry and force control of cell function
Authors: Freytes Donald O. , Wan Leo Q. , Vunjak‐Novakovic Gordana 
Published: September 2009

AbstractTissue engineering is becoming increasingly ambitious in its efforts to create functional human tissues, and to provide stem cell scientists with culture systems of high biological fidelity. Novel engineering designs are being guided by biological principles, in an attempt to recapitulate more faithfully the complexities of native cellular milieu. Three‐dimensional (3D) scaffolds are being designed to mimic native‐like cell environments and thereby elicit native‐like cell responses. Also, the traditional focus on molecular regulatory factors is shifting towards the combined application of molecular and physical factors. Finally, methods are becoming available for the coordinated presentation of molecular and physical factors in the form of controllable spatial and temporal gradients. Taken together, these recent developments enable the interrogation of cellular behavior within dynamic culture settings designed to mimic some aspects of native tissue development, disease, or regeneration. We discuss here these advanced cell culture environments, with emphasis on the derivation of design principles from the development (the biomimetic paradigm) and the geometry‐force control of cell function (the biophysical regulation paradigm). J. Cell. Biochem. 108: 1047–1058, 2009. © 2009 Wiley‐Liss, Inc.
RNAi‐mediated silencing of insulin receptor substrate‐4 enhances actinomycin D‐ and tumor necrosis factor‐α‐induced cell death in hepatocarcinoma cancer cell lines
Authors: Cuevas Eva P. , Escribano Oscar , Monserrat Jorge , Martínez‐Botas Javier , Sánchez María G. , Chiloeches Antonio , Hernández‐Breijo Borja , Sánchez‐Alonso Verónica , Román Irene D. , Fernández‐Moreno Ma Dolores , Guijarro Luis G. 
Published: September 2009

AbstractInsulin receptor substrate‐4 (IRS‐4) transmits signals from the insulin‐like growth factor receptor (IGF‐IR) and the insulin receptor (IR) to the PI3K/AKT and the ERK1/2 pathways. IRS‐4 expression increases dramatically after partial hepatectomy and plays an important role in HepG2 hepatoblastoma cell line proliferation/differentiation. In human hepatocarcinoma, IRS‐4 overexpression has been associated with tumor development. Herein, we describe the mechanism whereby IRS‐4 depletion induced by RNA interference (siRNA) sensitizes HepG2 cells to treatment with actinomycin D (Act D) and combined treatment with Act D plus tumor necrosis factor‐α (TNF‐α). Similar results have been obtained in HuH 7 and Chang cell lines. Act D therapy drove the cells to a mitochondrial‐dependent apoptotic program involving cytochrome c release, caspase 3 activation, PARP fragmentation and DNA laddering. TNF‐α amplifies the effect of Act D on HepG2 cell apoptosis increasing c‐jun N‐terminal kinase (JNK) activity, IκB‐α proteolysis and glutathione depletion. IRS‐4 depleted cells that were treated with Act D showed an increase in cytochrome c release and procaspase 3 and PARP proteolysis with respect to control cells. The mechanism involved in IRS‐4 action is independent of Akt, IκB kinase and JNK. IRS‐4 down regulation, however, decreased γ‐glutamylcysteine synthetase content and cell glutathione level in the presence of Act D plus TNF‐α. These results suggest that IRS‐4 protects HepG2 cells from oxidative stress induced by drug treatment. J. Cell. Biochem. 108: 1292–1301, 2009. © 2009 Wiley‐Liss, Inc.
Role of the low‐density lipoprotein receptor‐related protein‐1 in regulation of chondrocyte differentiation
Authors: Kawata Kazumi , Kubota Satoshi , Eguchi Takanori , Moritani Norifumi H. , Shimo Tsuyoshi , Kondo Seiji , Nishida Takashi , Minagi Shogo , Takigawa Masaharu 
Published: September 2009

AbstractThe low‐density lipoprotein receptor‐related protein 1 (LRP1) is known as an endocytic and signal transmission receptor. We formerly reported the gene expression and the localization of LRP1 in cartilage tissue and chondrocytes, but its roles in the differentiation of chondrocytes remained to be investigated. Here, in order to address this issue, we employed RNAi strategy to knockdown lrp1 in chondrocytic cells and obtained findings indicating a critical role therein. As a result of lrp1 knockdown, aggrecan and col2a1 mRNA levels were decreased. However, that of col10a1 or mmp13 mRNA was rather increased. Under this condition, we performed a promoter assay for Axin2, which is known to be induced by activation of the WNT/β‐catenin (βcat) signaling pathway. Thereby, we found that Axin2 promoter activity was enhanced in the lrp1 knockdown cells. Furthermore, when the WNT/β–catenin pathway was activated in chondrocytic cells by WNT3a or SB216763, which inhibits the phosphorylation of GSK3β, the mRNA levels of aggrecan and col2a1 were decreased, whereas that of mmp13 was increased. Additionally, the level of phosphorylated protein kinase C (PKC) ζ was also decreased in the lrp1 knockdown cells. When the phosphorylation of PKCζ was selectively inhibited, aggrecan and col2a1 mRNA levels decreased, whereas the mmp13 mRNA level increased. These data demonstrate that LRP1 exerts remarkable effects to retain the mature phenotype of chondrocytes as a critical mediator of cell signaling. Our findings also indicate that the onset of hypertrophy during endochondral ossification appears to be particularly dependent on the WNT and PKC signaling initiated by LRP1. J. Cell. Physiol. 222:138–148, 2010. © 2009 Wiley‐Liss, Inc.
Melanocytes in development and cancer
Authors: Uong Audrey , Zon Leonard I. 
Published: September 2009

AbstractMelanocytes are pigment‐producing cells in the skin of humans and other vertebrates. A number of genes involved in melanocyte development and vertebrate pigmentation have been characterized, largely through studies of a diversity of pigment mutations in a variety of species. Embryonic development of the melanocyte initiates with cell fate specification in the neural crest, which is then followed by cell migration and niche localization. Many genes involved in melanocyte development have also been implicated in the development of melanoma, an aggressive and fatal form of skin cancer that originates in the melanocyte. Although early stage melanomas that have not spread to the lymph nodes can be excised with little risk of recurrence, patients diagnosed with metastatic melanoma have a high mortality rate due to the resistance of most tumors to radiotherapy and chemotherapy. Transformed melanocytes that develop into melanomas proliferate abnormally and often begin to grow radially in the skin. Vertical growth can then follow this radial growth, leading to an invasion through the basement membrane into the underlying dermis and subsequent metastasis. It is still unclear, however, how a normal melanocyte becomes a melanoma cell, and how melanoma utilizes the properties of the normal melanocyte and its progenitors in its progression. The goal of this mini‐review is to highlight the role of melanocyte developmental pathways in melanoma, and to discuss recent studies and tools being used to illuminate this connection. J. Cell. Physiol. 222:38–41, 2010. © 2009 Wiley‐Liss, Inc.
Low oxygen reduces the modulation to an oxidative phenotype in monolayer‐expanded chondrocytes
Authors: Heywood Hannah K. , Lee David A. 
Published: September 2009

AbstractAutologous chondrocyte implantation requires a phase of in vitro cell expansion, achieved by monolayer culture under atmospheric oxygen levels. Chondrocytes reside under low oxygen conditions in situ and exhibit a glycolytic metabolism. However, oxidative phosphorylation rises progressively during culture, with concomitant reactive oxygen species production. We determine if the high oxygen environment in vitro provides the transformation stimulus. Articular chondrocytes were cultured in monolayer for up to 14 days under 2%, 5%, or 20% oxygen. Expansion under 2% and 5% oxygen reduced the rate at which the cells developed an oxidative phenotype compared to 20% oxygen. However, at 40 ± 4 fmol cell−1 h−1 the oxygen consumption by chondrocytes expanded under 2% oxygen for 14 days was still 14 times the value observed for freshly isolated cells. Seventy‐five to 78% of the increased oxygen consumption was accounted for by oxidative phosphorylation (oligomycin sensitive). Expansion under low oxygen also reduced cellular proliferation and 8‐hydroxyguanosine release, a marker of oxidative DNA damage. However, these parameters remained elevated compared to freshly isolated cells. Thus, expansion under physiological oxygen levels reduces, but does not abolish, the induction of an oxidative energy metabolism. We conclude that simply transferring chondrocytes to low oxygen is not sufficient to either maintain or re‐establish a normal energy metabolism. Furthermore, a hydrophobic polystyrene culture surface which promotes rounded cell morphology had no effect on the development of an oxidative metabolism. Although the shift towards an oxidative energy metabolism is often accompanied by morphological changes, this study does not support the hypothesis that it is driven by them. J. Cell. Physiol. 222:248–253, 2010. © 2009 Wiley‐Liss, Inc.
Huperzine a improves chronic inflammation and cognitive decline in rats with cerebral hypoperfusion
Authors: Wang Juan , Zhang Hai Yan , Tang Xi Can 
Published: September 2009

AbstractChronic cerebral hypoperfusion has been suggested to contribute to the progression of dementia. Inflammation and white matter lesion (WML) are involved in the pathologic process. This study investigated whether huperzine A, a natural acetylcholinesterase (AChE) inhibitor, has beneficial effects on long‐lasting inflammation as well as cognitive impairment in a rat model of cerebral hypoperfusion and how it plays these roles. Chronic cerebral hypoperfusion was induced by occlusion of bilateral common carotid arteries (two‐vessel occlusion; 2VO). Huperzine A was initially given 150 min after 2VO and daily for 3, 7, 14, and 28 days. Learning and memory dysfunction as tested by Morris water maze performance was observed in 2VO‐operated rats and was significantly improved by huperzine A treatment. WML and activation staining of immune cells were evaluated by Klüver‐Barrera (KB) and immunohistochemistry, respectively. Myelin damage and increased immunostains were found in optic tract at all indicated days. Huperzine A treatment significantly ameliorated all these phenomena. Moreover, huperzine A also suppressed overexpression of the inflammatory factor tumor necrosis factor‐α (TNF‐α) and overphosphorylation of JNK and p38 mitogen‐activated protein kinases (MAPKs) in a cell model of chronic hypoxia. Preincubation with mecamylamine (MEC), a nicotinic acetylcholine receptor (nAChR) antagonist, for 30 min before hypoxia notably reversed the effects of huperzine A on TNF‐α production and MAPKs phosphorylation. In conclusion, delayed and chronic administration of huperzine A could protect against 2VO‐induced cognitive impairment, which might be related to its beneficial effects on WML, and the nAChR‐dependent cholinergic anti‐inflammation pathway plays an important role. © 2009 Wiley‐Liss, Inc.
3‐nitropropionic acid‐induced mitochondrial permeability transition: Comparative study of mitochondria from different tissues and brain regions
Authors: Mirandola Sandra R. , Melo Daniela R. , Saito Ângela , Castilho Roger F. 
Published: September 2009

AbstractThe adult rat striatum is particularly vulnerable to systemic administration of the succinate dehydrogenase inhibitor 3‐nitropropionic acid (3NP), which is known to induce degeneration of the caudate‐putamen, as occurs in Huntington's disease. The aim of the present study was to compare the susceptibility of isolated mitochondria from different rat brain regions (striatum, cortex, and cerebellum) as well as from the liver, kidney, and heart to mitochondrial permeability transition (MPT) induced by 3NP and Ca2+. In the presence of micromolar Ca2+ concentrations, 3NP induces MPT in a dose‐dependent manner, as estimated by mitochondrial swelling and a decrease in the transmembrane electrical potential. A 3NP concentration capable of promoting a 10% inhibition of ADP‐stimulated, succinate‐supported respiration was sufficient to stimulate Ca2+‐induced MPT. Brain and heart mitochondria were generally more sensitive to 3NP and Ca2+‐induced MPT than mitochondria from liver and kidney. In addition, a partial inhibition of mitochondrial respiration by 3NP resulted in more pronounced MPT in striatal mitochondria than in cortical or cerebellar organelles. A similar inhibition of succinate dehydrogenase activity was observed in rat tissue homogenates obtained from various brain regions as well as from liver, kidney, and heart 24 hr after a single i.p. 3NP dose. Mitochondria isolated from forebrains of 3NP‐treated rats were also more susceptible to Ca2+‐induced MPT than those of control rats. We propose that the increased susceptibility of the striatum to 3NP‐induced neurodegeneration may be partially explained by its susceptibility to MPT, together with the greater vulnerability of this brain region to glutamate receptor‐mediated Ca2+ influx. © 2009 Wiley‐Liss, Inc.