bluuebunny/crossref_metadata_2025 huggingface dataset:
A Potential Synergistic Anticancer Effect of Paclitaxel and Amifostine on Endometrial Cancer
Authors: Dai Donghai , Holmes Anna M. , Nguyen Tan , Davies Suzy , Theele Daniel P. , Verschraegen Claire , Leslie Kimberly K.
Published: October 2005

Although paclitaxel is one of the most effective chemotherapeutic agents, its usefulness is still limited in advanced and recurrent endometrial cancer. Amifostine protection of normal tissues against the side effects of chemotherapeutic agents has been clinically proven in cancer patients; however, its application in endometrial cancer has not been fully evaluated. We have investigated the use of paclitaxel and amifostine in controlling the growth of poorly differentiated endometrial cancer cells, Hec50co, in vitro and in vivo. Our studies show that amifostine had direct anticancer effects on endometrial cancer cells in vitro by arresting the cell cycle at the G1 phase and inducing apoptosis. Amifostine also inhibited s.c. tumor growth in athymic mice. Paclitaxel IC50 value was reduced from 14 to 2 nmol/L with pretreatment of a single dose of 178 μmol/L of amifostine for 72 hours. Amifostine also synergized with paclitaxel in the arrest of the cell cycle at the G2-M phase and in the induction of apoptosis. This two-drug regimen inhibited s.c. tumor growth as well as improved mouse survival significantly more than paclitaxel alone. Amifostine also significantly improved paclitaxel-induced cytotoxic effects on peripheral blood profiles. Our studies show that amifostine has direct anticancer effects on endometrial cancer. Our data have also shown a potential anticancer synergy between amifostine and paclitaxel in vitro and in vivo, whereas amifostine maintained a protective role in peripheral blood profiles. The dual specificity of amifostine action should be further investigated.
Continuous MLL-ENL Expression Is Necessary to Establish a “Hox Code” and Maintain Immortalization of Hematopoietic Progenitor Cells
Authors: Horton Sarah J. , Grier David G. , McGonigle Glenda J. , Thompson Alexander , Morrow Michelle , De Silva Inusha , Moulding Dale A. , Kioussis Dimitris , Lappin Terence R.J. , Brady Hugh J.M. , Williams Owen
Published: October 2005

The t[(11;19)(p22;q23)] translocation, which gives rise to the MLL-ENL fusion protein, is commonly found in infant acute leukemias of both the myeloid and lymphoid lineage. To investigate the molecular mechanism of immortalization by MLL-ENL we established a Tet-regulatable system of MLL-ENL expression in primary hematopoietic progenitor cells. Immortalized myeloid cell lines were generated, which are dependent on continued MLL-ENL expression for their survival and proliferation. These cells either terminally differentiate or die when MLL-ENL expression is turned off with doxycycline. The expression profile of all 39 murine Hox genes was analyzed in these cells by real-time quantitative PCR. This analysis showed that loss of MLL-ENL was accompanied by a reduction in the expression of multiple Hoxa genes. By comparing these changes with Hox gene expression in cells induced to differentiate with granulocyte colony-stimulating factor, we show for the first time that reduced Hox gene expression is specific to loss of MLL-ENL and is not a consequence of differentiation. Our data also suggest that the Hox cofactor Meis-2 can substitute for Meis-1 function. Thus, MLL-ENL is required to initiate and maintain immortalization of myeloid progenitors and may contribute to leukemogenesis by aberrantly sustaining the expression of a “Hox code” consisting of Hoxa4 to Hoxa11.
Association between Large-scale Genomic Homozygosity without Chromosomal Loss and Nonseminomatous Germ Cell Tumor Development
Authors: Lu Yong-Jie , Yang Jinshu , Noel Elodie , Skoulakis Spyros , Chaplin Tracy , Raghavan Manoj , Purkis Trisha , Mcintyre Alan , Kudahetti Sakunthala C. , Naase Mahmoud , Berney Dan , Shipley Janet , Oliver R. Timothy D. , Young Bryan D.
Published: October 2005

The genotype of a tumor determines its biology and clinical behavior. The genetic alterations associated with the unique embryonal morphology of nonseminomatous subtypes of testicular germ cell tumors remain to be established. Using single nucleotide polymorphism microarray analysis, we found in all of the 15 nonseminomas analyzed, large-scale chromosomal homozygosities, most of which were not associated with relative chromosome loss. This unusual genotype, distinguishing nonseminoma from seminomas and other human tumors, may be associated with the special embryonal development morphologic transition of this malignancy. Based on these genetic data, we hypothesized a new potential origin of nonseminomas through sperm fusion. Nonrandom involvement of certain chromosomes also suggests that genes on these chromosome regions may play an important role in nonseminoma development.
Action of the Src Family Kinase Inhibitor, Dasatinib (BMS-354825), on Human Prostate Cancer Cells
Authors: Nam Sangkil , Kim Donghwa , Cheng Jin Q. , Zhang Shumin , Lee Ji-Hyun , Buettner Ralf , Mirosevich Janni , Lee Francis Y. , Jove Richard
Published: October 2005

Src family kinases (SFK) are currently being investigated as targets for treatment strategies in various cancers. The novel SFK/Abl inhibitor, dasatinib (BMS-354825), is a promising therapeutic agent with oral bioavailability. Dasatinib has been shown to inhibit growth of Bcr-Abl–dependent chronic myeloid leukemia xenografts in nude mice. Dasatinib also has been shown to have activity against cultured human prostate and breast cancer cells. However, the molecular mechanism by which dasatinib acts on epithelial tumor cells remains unknown. In this study, we show that dasatinib blocks the kinase activities of the SFKs, Lyn, and Src, in human prostate cancer cells at low nanomolar concentrations. Moreover, focal adhesion kinase and Crk-associated substrate (p130CAS) signaling downstream of SFKs are also inhibited at similar concentrations of dasatinib. Consistent with inhibition of these signaling pathways, dasatinib suppresses cell adhesion, migration, and invasion of prostate cancer cells at low nanomolar concentrations. Therefore, dasatinib has potential as a therapeutic agent for metastatic prostate cancers harboring activated SFK and focal adhesion kinase signaling.
Ionizing Radiation Activates Late Herpes Simplex Virus 1 Promoters via the p38 Pathway in Tumors Treated with Oncolytic Viruses
Authors: Mezhir James J. , Advani Sunil J. , Smith Kerrington D. , Darga Thomas E. , Poon Alice P.W. , Schmidt Hank , Posner Mitchell C. , Roizman Bernard , Weichselbaum Ralph R.
Published: October 2005

Ionizing radiation potentiates the oncolytic activity of attenuated herpes simplex viruses in tumors exposed to irradiation at specific time intervals by inducing higher virus yields. Cell culture studies have shown that an attenuated virus lacking the viral γ134.5 genes underproduces late proteins whose synthesis depends on sustained synthesis of viral DNA. Here we report that ionizing radiation enhances gene expression from late viral promoters in transduced cells in the absence of other viral gene products. Consistent with this result, we show that in tumors infected with the attenuated virus, ionizing radiation increases 13.6-fold above baseline the gene expression from a late viral promoter as early as 2 hours after virus infection, an interval too short to account for viral DNA synthesis. The radiation-dependent up-regulation of late viral genes is mediated by the p38 pathway, inasmuch as the enhancement is abolished by p38 inhibitors or a p38 dominant-negative construct. The p38 pathway is not essential for wild-type virus gene expression. The results suggest that ionizing radiation up-regulates late promoters active in the course of viral DNA synthesis and provide a rationale for use of radiation to up-regulate cytotoxic genes introduced into tumor cells by viral vectors for cytoreductive therapy.
GlutathioneS-Transferase π1 Promotes Tumorigenicity in HCT116 Human Colon Cancer Cells
Authors: Dang Duyen T. , Chen Fang , Kohli Manu , Rago Carlo , Cummins Jordan M. , Dang Long H.
Published: October 2005

GSTP1 is a member of the glutathione S-transferase enzyme superfamily, which catalyzes the conjugation of electrophiles with glutathione in the process of detoxification. GSTP1 is widely overexpressed in colorectal cancer, from aberrant crypt foci to advanced carcinomas. Increased expression of GSTP1 is associated with multidrug resistance and a worse clinical prognosis. However, GSTP1-null mice have an increased risk of tumor formation. Thus, the biological function of GSTP1 in colorectal cancer biology remains speculative. In an effort to gain further insights into the role of GSTP1 in tumorigenesis, we disrupted the GSTP1 gene in HCT116 human colorectal cancer cells using targeted homologous recombination. We find that loss of GSTP1 resulted in impaired clonogenic survival and proliferation. Specifically, under growth-limiting conditions, (a) GSTP1 protected HCT116 cells from oxidative stress and associated apoptosis and (b) promoted mitogen-activated protein kinase-extracellular signal-regulated kinase kinase/extracellular signal-regulated kinase–mediated G1-S cell cycle progression. In vivo, GSTP1 was critical for engraftment and growth of HCT116 tumor xenografts. These studies directly show that GSTP1 promotes clonogenic survival and proliferation in HCT116 human colon cancer cells.
The Scatter Factor/Hepatocyte Growth Factor: c-Met Pathway in Human Embryonal Central Nervous System Tumor Malignancy
Authors: Li Yunqing , Lal Bachchu , Kwon Sherwin , Fan Xing , Saldanha Usha , Reznik Thomas E. , Kuchner Eric B. , Eberhart Charles , Laterra John , Abounader Roger
Published: October 2005

Embryonal central nervous system (CNS) tumors, which comprise medulloblastoma, are the most common malignant brain tumors in children. The role of the growth factor scatter factor/hepatocyte growth factor (SF/HGF) and its tyrosine kinase receptor c-Met in these tumors has been until now completely unknown. In the present study, we show that human embryonal CNS tumor cell lines and surgical tumor specimens express SF/HGF and c-Met. Furthermore, c-Met mRNA expression levels statistically significantly correlate with poor clinical outcome. Treatment of medulloblastoma cells with SF/HGF activates c-Met and downstream signal transduction as evidenced by c-Met, mitogen-activated protein kinase, and Akt phosphorylation. SF/HGF induces tumor cell proliferation, anchorage-independent growth, and cell cycle progression beyond the G1-S checkpoint. Using dominant-negative Cdk2 and a degradation stable p27 mutant, we show that cell cycle progression induced by SF/HGF requires Cdk2 function and p27 inhibition. SF/HGF also protects medulloblastoma cells against apoptosis induced by chemotherapy. This cytoprotective effect is associated with reduction of proapoptotic cleaved poly(ADP-ribose) polymerase and cleaved caspase-3 proteins and requires phosphoinositide 3-kinase activity. SF/HGF gene transfer to medulloblastoma cells strongly enhances the in vivo growth of s.c. and intracranial tumor xenografts. SF/HGF-overexpressing medulloblastoma xenografts exhibit increased invasion and morphologic changes that resemble human large cell anaplastic medulloblastoma. This first characterization establishes SF/HGF:c-Met as a new pathway of malignancy with multifunctional effects in human embryonal CNS tumors.
Nox4 Is Critical for Hypoxia-Inducible Factor 2-α Transcriptional Activity in von Hippel-Lindau–Deficient Renal Cell Carcinoma
Authors: Maranchie Jodi K. , Zhan Ye
Published: October 2005

Inactivation of the von Hippel-Lindau tumor suppressor (VHL) is an early event in >60% of sporadic clear cell renal cell carcinoma (RCC). Loss of VHL E3 ubiquitin ligase function results in accumulation of the α-subunit of the hypoxia-inducible heterodimeric transcription factor (HIF-α) and transcription of an array of genes including vascular endothelial growth factor, transforming growth factor-α, and erythropoietin. Studies have shown that HIF-α can be alternatively activated by reactive oxygen species. Nox4 is an NADP(H) oxidase that generates signaling levels of superoxide and is found in greatest abundance in the distal renal tubules. To determine if Nox4 contributes to HIF activity in RCC, we examined the impact of Nox4 expression on HIF-α expression and transactivation. We report here that small inhibitory RNA (siRNA) knockdown of Nox4 in 786-0 human renal tumor cells expressing empty vector (PRC) or wild-type VHL (WT) results in 50% decrease in intracellular reactive oxygen species as measured by a fluorescent 2′,7′-dichlorofluorescin diacetate assay, and >85% reduction in HIF2-α mRNA and protein levels by quantitative reverse transcription-PCR and Western blot analysis. Furthermore, expression of the HIF target genes, vascular endothelial growth factor, transforming growth factor-α, and Glut-1 was abrogated by 93%, 74%, and 99%, respectively, after stable transfection with Nox4 siRNA relative to nontargeting siRNA, as determined by quantitative reverse transcription-PCR. Thus, renal Nox4 expression is essential for full HIF2-α expression and activity in 786-0 renal tumor cells, even in the absence of functional VHL. We propose the use of Nox4 as a target in the treatment of clear cell RCC.
Recent Advances in Understanding the Antineoplastic Mechanisms of Farnesyltransferase Inhibitors
Authors: Pan Jingxuan , Yeung Sai-Ching Jim
Published: October 2005

Farnesyltransferase (FTase) inhibitors (FTI) have broad antineoplastic actions targeting both cancer cells and mesenchymal cells involved in tumor angiogenesis. The small GTPases H-Ras, Rheb, and RhoB and the centromere proteins CENP-E and CENP-F are relevant targets of farnesylation inhibition; however, their relative importance in the antineoplastic effect of FTIs may vary in different cell types at different stages of the cell cycle and at different stages in oncogenesis. Three recent studies argue that Ras-independent and perhaps even FTase-independent properties are important to the antineoplastic action of this class of drugs. In mice, genetic ablation of FTase does not abolish the oncogenic activity of Ras, limiting the original conception of FTIs as an effective means to target Ras in cancer cells. FTase may not be the sole molecular target of these agents, and one study has suggested that FTIs act by targeting geranylgeranyl transferase II. Lastly, we have obtained evidence that induction of reactive oxygen species and reactive oxygen species–mediated DNA damage by FTIs may be critical for their antineoplastic action as a class. Together, these findings may alter thinking about how to apply FTIs in the clinic.
Targeting Myelomonocytic Cells to Revert Inflammation-Dependent Cancer Promotion
Authors: Colombo Mario P. , Mantovani Alberto
Published: October 2005

Tumor development and progression are strongly linked to inflammation and the presence of tumor-associated macrophages (TAMs). In murine tumors, antitumor activity can be achieved by targeting TAM recruitment, survival, activation, polarization, effector signaling, or extracellular matrix interactions. Thus, it may be possible to increase the efficacy of conventional cancer therapeutic strategies by targeting TAMs.
Autocrine Expression of Platelet-Derived Growth Factor B in B Cell Chronic Lymphocytic Leukemia
Authors: Ho Ching-Liang , Hsu Lai-Fa , Phyliky Robert L. , Li Chin-Yang
Published: October 2005

Platelet-derived growth factor (PDGF) regulates clonal proliferation of malignant pre-B cell lines, but little is known about its role in normal B lymphocyte differentiation and malignant transformation. To understand the expression of PDGF-A, PDGF-B and the β-receptor (PDGF-Rβ) in B cell lymphoproliferative disorders, we used an immunohistochemical method to stain formalin-fixed, paraffin-embedded tissues in 5 patients with reactive lymphoid hyperplasia, 15 with non-Hodgkin’s lymphoma and 23 with B cell chronic lymphocytic leukemia (B-CLL). Abundant PDGF-A, rather than PDGF-B, was expressed in normal B cell differentiation. There was no difference in the expression of PDGF-A and PDGF-B between patients with reactive lymphoid hyperplasia and patients with malignant lymphoproliferative disorders. Among the patients with B-CLL, the expression of PDGF-B was much stronger than the expression of PDGF-A, and 18 of the patients had coexpression of PDGF-B and PDGF-Rβ. A larger proportion of patients with B-CLL than with non-Hodgkin’s lymphoma had expression of PDGF-B and PDGF-Rβ. In conclusion, PDGF-A expression in all stages of B lymphocyte differentiation suggests that it is important in B cell differentiation and proliferation. Expression of PDGF-B and PDGF-Rβ suggests that autocrine signaling of PDGF may be important in malignant transformation of B-CLL. However, further studies are necessary to confirm these conclusions.
Automated Analyzer Evaluation of Reticulocytes in Bone Marrow and Peripheral Blood of Hematologic Disorders
Authors: Hirose Asao , Yamane Takahisa , Shibata Hisako , Kamitani Tomio , Hino Masayuki
Published: October 2005

The R-3000 reticulocyte analyzer uses flow cytometry with an argon laser as its light source. This analyzer stains residual RNA with auramine O to provide a reticulocyte maturation differential. Using the R-3000, we analyzed 119 samples of bone marrow (BM) and peripheral blood (PB) from 111 patients with hematologic disorders. Parameters were reticulocytes, immature reticulocyte fraction (IRF) percentage in BM and PB, BM/PB reticulocyte ratio, and BM/PB IRF ratio. Reticulocytes and IRF percentage in BM were significantly higher than in PB (p < 0.01). There was also a good correlation between reticulocyte percentages in BM and in PB (r = 0.81). Patients were classified into a normal group (without anemia) and an anemia group. Furthermore, the anemia group was classified into three groups: group 1: cases with hematopoietic dysfunction; group 2: cases in bone marrow recovery phase after chemotherapy and hematopoietic stem cell transplantation, and hematologic disorders with bone marrow accelerative phase, and group 3: cases with ineffective hematopoiesis (myelodysplastic syndrome). The mean reticulocyte percentage of the normal group was 2.3 ± 1.1%, which was close to the normal value in BM. The BM/PB reticulocyte ratio of group 3 was statistically higher than that of groups 1 and 2. This indicates that group 3 had ineffective erythropoiesis and that the BM/PB ratio is a useful indicator for the diagnosis of myelodysplastic syndrome.
Safety and Effectiveness of 100 mg/kg/day Deferiprone in Patients with Thalassemia Major: A Two-Year Study
Authors: Taher Ali , Sheikh-Taha Marwan , Sharara Ala , Inati Adlette , Koussa Suzane , Ellis Gareth , Dhillon A.P. , Hoffbrand A.V.
Published: October 2005

Deferiprone at a dose of 75 mg/kg/day is not sufficiently effective to maintain iron stores at a level which has been considered safe in all patients with iron overload. Our main aim was to determine the safety of long-term therapy with high-dose (100 mg/kg/day) deferiprone. A secondary aim was to determine the efficacy of this high dose. Twelve thalassemia major patients received deferiprone at a dose of100 mg/kg/day over 2 years. Transient aspartate aminotransferase increase (8 patients), gastrointestinal discomfort (3 patients) and arthralgia (2 patients) were the most commonly reported side effects. None of the patients discontinued therapy. The mean serum ferritin level fell from 3,901 ± 3,618 to 1,790 ± 2,205 µg/l after 2 years (p < 0.05). Five of the 12 patients continued to receive deferiprone for an additional 3 years. No new side effects were encountered. The mean serum ferritin level in this subgroup was initially 2,510 ± 332 µg/l and dropped to 1,511 ± 664 µg/l after 5 years (p < 0.05). Liver iron levels at the end of the 2-year study ranged from 1.0 to 30.9 mg/g dry weight, 3 of the patients having levels above 15 mg/g.
Tyrosine Kinase Inhibitor STI571 (Imatinib) Cooperates with Wild-Type p53 on K562 Cell Line to Enhance Its Proapoptotic Effects
Authors: Brusa Gianluca , Mancini Manuela , Campanini Fabio , Calabrò Alberto , Zuffa Elisa , Barbieri Enza , Santucci Maria Alessandra
Published: October 2005

In order to ascertain whether p53 has a role in chronic myeloid leukemia hematopoietic progenitor response to the innovative tyrosine kinase inhibitor STI571 (Imatinib), we overexpressed a wild type (wt) p53 construct in the K562 cell line, generated from a human blast crisis and lacking endogenous p53. Wt p53 overexpression was associated with a significant reduction of bcr-abl expression levels resulting, at least in part, from post-transcriptional events affecting the stability of p210 bcr-abl fusion protein. Moreover, we demonstrated that p53 overexpression enhances the commitment to the apoptotic death fate of K562 following its in vitro exposure to 1 µM STI571. Multiple mechanisms are involved in p53 impact on K562 survival: Most importantly, we found that a greater reduction of bcr-abl transcription by STI571 was associated with the overexpression of wt p53. Further studies are required to elucidate the mechanisms involved in the transcriptional repression of bcr-abl by STI571 and p53 and in their synergic effects on the clonal hematopoiesis of chronic myeloid leukemia.
Shape of the Lateral Mandibular Outline in Lemuridae: A Quantitative Analysis of Variability Using Elliptical Fourier Analysis
Authors: Raveloson Herimalala , Le Minor Jean-Marie , Rumpler Yves , Schmittbuhl Matthieu
Published: October 2005

While several morphometric analyses in lemurids have focused on the craniofacial complex, the characterization of their mandibular morphology has received less attention. The mandibular outline, in lateral perspective, was quantified using elliptical Fourier analysis, in an osteological sample encompassing 189 lemurid mandibles (66 Eulemur, 51 Hapalemur, 22 Lemur and 50 Varecia), and compared using multivariate statistical techniques. The taxonomic value of this outline in Lemuridae was demonstrated by the existence of significant separations between the four genera studied. In particular, the mandibular morphology of Hapalemur was markedly different from that in the group Eulemur-Lemur-Varecia. Excluding Hapalemur from analysis, the distinctions between Eulemur, Lemur and Varecia were enhanced suggesting the existence of more subtle intergeneric differences in mandibular morphology. Variation in mandibular form was greatest in Hapalemur and smallest in Eulemur and Varecia (as demonstrated by the mean values of interindividual distances); variation was higher in Lemur than in Eulemur and Varecia, but not higher than in Hapalemur. This morphological diversity may be related to functional adaptation in response to particular dietary habits. The patterns of intergeneric and intrageneric shape variations of the mandible in Lemuridae presented here provide a valuable resource for the analysis of variation among living and fossil lemurids.
Anatomy of the Hand and Arm in Daubentonia madagascariensis :A Functional and Phylogenetic Outlook
Authors: Soligo Christophe
Published: October 2005

The aye-aye (Daubentonia madagascariensis) is easily the most enigmatic of living primates. It sports a unique combination of derived characters, including continuously growing incisors, functional claws, the largest hand of any primate and a highly modified middle finger. The specialised middle finger is no longer used in locomotion and serves as a probe-like instrument for investigating, locating and extracting xylophagous (wood-boring) larvae as well as other food items. Its phalanges can be moved both at great speed and independently of each other. The present study reports on dissections of the forelimbs of two individuals of D. madagascariensis and one specimen each of Lemur catta and Cercopithecus cephus. Derived characters of the forelimb musculature in Daubentonia are interpreted within the context of its distinct locomotor and foraging adaptations. The primary adaptations underlying speed and mobility in the third manual digit of Daubentonia are found in the intrinsic hand musculature and notably in the arrangement of the dorsal aponeurosis. Implications for the interpretation of suggested convergences between the aye-aye, the diprotodont marsupial Dactylopsila palpator and the early Tertiary apatemyid genus Heterohyus are discussed.
Effect of Atorvastatin on in vitro Expression of Resistin in Adipocytes and Monocytes/Macrophages and Effect of Atorvastatin Treatment on Serum Resistin Levels in Patients with Type 2 Diabetes
Authors: Ichida Yukiko , Hasegawa Goji , Fukui Michiaki , Obayashi Hiroshi , Ohta Mitsuhiro , Fujinami Aya , Ohta Kiyoe , Nakano Koji , Yoshikawa Toshikazu , Nakamura Naoto
Published: October 2005

Resistin is a novel cysteine-rich protein that plays a role in the development of insulin resistance and atherosclerosis. HMG-CoA reductase inhibitors (statins) possess anti-inflammatory properties that are independent of their lipid-lowering action. The aims of this study were to investigate the effect of atorvastatin on expression of resistin in vitro and to determine the effect of 6 months of treatment with atorvastatin on serum levels of resistin in patients with type 2 diabetes. 3T3-L1 adipocytes and human monocytes/macrophages and preadipocytes were incubated with 1 and 10 µmol/l atorvastatin for 24 and 48 h, followed by measurement of resistin mRNA by the quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR). Serum resistin concentration in the patients with type 2 diabetes was measured at baseline and after 6 months of atorvastatin treatment (10 mg/day). qRT-PCR analysis revealed that atorvastatin decreased resistin mRNA expression in a dose- and time-dependent manner. Serum resistin concentration tended to decrease after 6 months of atorvastatin treatment, although this decrease did not reach statistical significance. In conclusion, the findings of our in vitro study contribute to the growing volume of evidence on the anti-inflammatory and anti-atherosclerotic effects of statins, and led us to suggest that statins may control inflammatory responses by inhibiting expression of resistin mRNA. It is necessary to confirm the findings of our in vitro study by an appropriately designed large-scale clinical study.
Topotecan in Platinum-Resistant Epithelial Ovarian Cancer
Authors: Karabulut Bulent , Sezgin Canfeza , Terek Mustafa Cosan , Uslu Ruchan , Sanli Ulus A. , Akman Levent , Ozsaran Aydin , Dikmen Yilmaz , Goker Erdem
Published: October 2005

Background: Topotecan has been emerged as a new promising anticancer drug for patients with ovarian cancer. Methods: In this study, patients who were treated with topotecan were reviewed retrospectively. A total of 26 patients was included the study. All patients had received platinum-based regimens previously. Topotecan was administered a dose of 1.5 mg/m2 intravenously 30 min daily for 5 days and repeated every 21 days. Results: The response rates were 30% by CA-125 level and 29% in clinic evaluation. Median duration of response was 8 (3–15) months, median progression-free interval was 12 (4–30) months and median overall survival was 15 (4–36) months. Grade 3–4 neutropenia occurred in 58% of the patients (38% of the courses) and trombocytopenia in 29% of the patients (12% of the courses). Nonhematological toxicities were mild. There was no drug-related death. Conclusion: Topotecan is considered as a reasonable option for treatment of patients with platinum refractory recurrent ovarian cancer.
Antineoplastic Strategy: Irreversible Tumor Blood Flow Stasis Induced by the Combretastatin A-4 Derivative AVE8062 (AC7700)
Authors: Hori Katsuyoshi
Published: October 2005

Despite extensive research efforts, effective therapies for refractive cancers have not yet been established, and development of successful treatment strategies remains the most important task in the field of oncology. We recently showed that AVE8062 (formerly AC7700), a derivative of combretastatin A-4, achieved irreversible stasis of tumor blood flow (TBF), thereby causing necrosis of tumor tissue by halting the supply of nutrients. Such effects were unrelated to cancer type. In this review, we summarize our experiments on antivascular and antitumor effects by AVE8062. We maintain that such starvation tactics against solid tumors constitute a new therapeutic strategy for all solid tumors, including refractory cancers.
Treatment of Patients with Pyogenic Liver Abscess
Authors: Cerwenka H. , Bacher H. , Werkgartner G. , El-Shabrawi A. , Kornprat P. , Bernhardt G.A. , Mischinger H.J.
Published: October 2005

Background: Pyogenic liver abscess (PLA) remains a serious disease with a mortality of 6–14%. Methods: Clinical data of 76 patients with PLA were analyzed. Treatment options comprised antibiotics, percutaneous puncture/drainage, endoscopic papillotomy/stenting and/or surgery as indicated. Results: Fifty-eight patients (76%) had single and 18 patients multiple PLA (right lobe: 65%; both lobes: 22%). The most frequent etiologies were: biliary (38%), hematogenous and posttraumatic (11%). Factors associated with the need for surgery included gallbladder empyema, biliary fistulas, malignancy, perforation, multicentricity, vascular complications and foreign bodies (e.g. infected ventriculo-peritoneal shunt, toothpick). Conclusions: Microbiological testing provides important information for treatment monitoring and modification. Complementary assessment of risk factors for a complicated course is crucial for timely identification of patients requiring additional treatment.
Inhibition of Inducible Nitric Oxide Synthase Alters Thy-1 Glomeruonephritis in Rats
Authors: Satriano Joseph , Lortie Mark J. , Ishizuka Shunji , Valdivielso José M. , Friedman Beth , Munger Karen A.
Published: October 2005

Background/Aims: Inducible nitric oxide (NO) synthase (iNOS) generated NO increases in the early phase of Thy-1 glomerulonephritis concurrently with mesangiolysis and reduction in glomerular filtration rate (GFR). Activation of ornithine decarboxylase (ODC), the rate-limiting enzyme of polyamine biosynthesis, is upregulated to allow mesangial cell proliferation which constitutes the repair phase in this model. Antiproliferative high-output NO generation inhibits proproliferative ODC activity, thereby temporally separating the early ‘bactericidal’ phase from the later ‘growth’ repair phase. Methods: Renal function, ODC protein expression, arginine, ornithine, and polyamines by high-performance liquid chromatography, and histological changes were assessed in rats after induction of Thy-1 nephritis with and without NOS inhibition. Results: Thy-1 significantly reduced the GFR relative to untreated controls. Treatment with a nonspecific NOS inhibitor, but not a selective iNOS inhibitor, further decreased the GFR at day 1. This implys a protective role for constitutive NOS in the early phase of this inflammatory model. Selective iNOS inhibition abrogated increased plasma NO2/NO3 levels in Thy-1 glomerulonephritis, but did not significantly reduce mesangiolysis. However, inhibition of iNOS did result in significantly more nuclei/glomerulus during the proliferative phase, increasing the hypercellularity component of this disease model. This correlates with increased levels of polyamines, ornithine, and arginine beyond those observed with Thy-1 administration alone. Conclusions: These studies provide evidence that NO generation from different NOS isoforms can be protective in the temporal course of Thy-1 glomerulonephritis. The finding that iNOS attenuates hypercellularity in the repair phase of this inflammatory model adds cautionary insight in the therapeutic use of selective iNOS inhibition in vivo.
Osteoporosis due to Glucocorticoid Use in Children with Chronic Illness
Authors: Ward Leanne M.
Published: October 2005

Osteoporosis is increasingly recognized as a complication of chronic childhood illnesses, particularly when glucocorticoids (GCs) are necessary for treatment. Elucidation of the mechanisms leading to bone fragility in these settings requires disentanglement of the relative contributions of myriad risk factors, including disease activity, muscle weakness, immobilization, delayed growth and puberty, compromised nutrition, and osteotoxic medications. Over the years, bone mass and density evaluations by dual energy X-ray absorptiometry (DXA) have become popular for assessing bone health in children; however, such measurements are difficult to interpret because of the confounding effect of bone size and the lack of DXA-based densitometric criteria for defining osteoporosis in childhood. Recently, a new diagnostic approach for evaluation of densitometric data in children has been suggested, driven by Frost’s mechanostat theory. A diagnostic algorithm based on the mechanostat theory of bone-muscle development is proposed for the characterization of bone disease in children with chronic illness. In addition to DXA-based assessments, techniques such as peripheral quantitative computerized tomography and ilial histomorphometry, for which there are pediatric reference data, are gaining ground in the characterization of skeletal changes due to chronic illness. Although these diagnostic techniques expand our understanding of osteoporosis in children, they do not replace clinical assessment. Concrete clinical evidence for GC-induced bone fragility can be seen in spinal changes due to vertebral compression, with spinal morphometry emerging as an essential, but frequently overlooked, tool in the evaluation of children’s bone health. Presently, osteoporosis treatment in the chronic illness setting remains experimental and should be restricted to clinical studies. Following an understanding of the natural history of GC-induced osteoporosis in children, randomized, placebo-controlled prevention and intervention trials will be the next step toward the development of clinical practice guidelines.
Prognostic Significance of Blood Brain Barrier Permeability in Acute Hemorrhagic Stroke
Authors: Lampl Yair , Shmuilovich Olga , Lockman Judith , Sadeh Menahem , Lorberboym Mordechai
Published: October 2005

Background: Blood brain barrier (BBB) disruption is accompanied by edema in the surrounding areas of the intracerebral hemorrhage (ICH). The aim of the study was to clarify the correlation between BBB breakdown and outcome in ICH. Patients: Twenty-seven patients with primary ICH were included in the study. Each patient underwent CT and DTPA-SPECT, and the National Institutes of Health (NIH) and modified Rankin score were performed as well. Results: DTPA-SPECT had a significant correlation with the modified Rankin score after 3 months (p = 0.008) and 6 months (p = 0.01). The CT scan was directly correlated with the NIH score on days 1, 7 and 30 (p = 0.01, p = 0.01 and p = 0.04, respectively). No correlation was found between DTPA-SPECT and CT scan data. Conclusions: The degree of BBB breakdown, as imaged by the DTPA-SPECT technique, was directly correlated with the late functional outcome. The CT scan has an inverse correlation with the NIH score. These findings may have broad clinical implications.
Somite as a Morphological Reference for Staging and Axial Levels of Developing Structures in Mouse Embryos
Authors: Chan Angel On Kei , Dong Ming , Wang Liang , Chan Wood Yee
Published: October 2005

Background: The embryonic staging system based on the number of days post coitum is not always adequate to describe the rapid changes that occur during early organogenesis, and appropriate morphological features that can be easily referred to are important in descriptive embryology. Aims: The present study aims to ascertain whether somites can be used to determine both the developmental stage of mouse embryos and the axial level of embryonic structures from 9.5 days post coitum onwards. Results: The somite number could be easily counted after cresyl violet staining from 9.5 to 12.5 days post coitum, and the first few somites started to de-epithelialize by 10.0 days post coitum. However, from 12.5 days post coitum onwards, somites became difficult to count because of the thick surface epithelium. Vital dye labelling followed by whole embryo culture demonstrated that somites, limb buds and various regions of the neural tube did not undergo any major positional shift in relation to each other. Conclusions: From 9.5 to 12.5 days post coitum, the ease of somite count and the minimal positional shift in somites, limb buds and the neural tube implicate that the somite can be a convenient morphological reference for both the embryonic stage and the axial level of developing structures including limb buds and different regions of the neural tube during this period.
Venous thromboembolism and fractured neck of femur
Authors: Hitos Kerry , Fletcher John
Published: October 2005

The post-operative incidence of venous thromboembolism (VTE) is high for patients undergoing hip fracture surgery. Proven prophylactic measures are available although underutilized due to concern on post-operative bleeding with use of anticoagulants. This study retrospectively reviewed the clinical incidence of VTE and utilisation of thromboprophylactic protocols over an eight year period. Demographic details, mechanism of injury, VTE risk factors, prophylactic modalities (mechanical and pharmacological), operation duration, mode of anaesthesia, hospital length of stay (LOS) and post-operative complications with particular attention to suspected deep vein thrombosis (DVT) and/or pulmonary embolism (PE) were analysed. Male to female ratio was 1: 2.7 with a median age of 78 years (IQR: 70–86 years) and 83 years (IQR: 77–87 years) respectively (p<0.001). Median hospital LOS was 8 days (IQR: 5–13 days) and differed with mechanism of injury. The in-hospital incidence of VTE was 1.6% (95% CI:1.1–2.5%) with a probably underestimated three month rate of 8.2% (95% CI:5.3–12.4%). Non fatal PE was 0.5% (95% CI: 0.2–1.0%) in-hospital and 2.6% (95% CI: 1.2–5.5%) at three months. Fatal PE was 0.5% (95% CI: 0.2–1.0%) with a three month incidence of 0.4% (95% CI: 0.1–2.4%). The in-hospitalVTE incidence was kept relatively low with use of prophylactic protocols with almost all patients receiving prophylaxis by the end of the study period. Given the five-fold out of hospital increase in incidence, consideration should be given to continue prophylaxis beyond hospital discharge in this high risk group of patients.
Local delivery of 17β-estradiol improves reendothelialization and decreases inflammation after coronary stenting in a porcine model
Authors: Chandrasekar Baskaran , Sirois Martin , Geoffroy Pascale , Lauzier Dominique , Nattel Stanley , Tanguay Jean-François
Published: October 2005

In the current study, we investigated the effect of local intravascular delivery of 17β-estradiol (17β-E) on subsequent instent neointimal hyperplasia. Twenty-seven stents were implanted in coronary arteries of juvenile swine. Coronary arteries were randomized to local treatment with 17β-E or no drug therapy (control-vehicle treated). Twenty-eight days posttreatment, angiographic images revealed an improved minimal lumen diameter (2.2 ± 0.2 vs. 1.3 ± 0.2 mm, P < 0.005) and a reduction of late lumen loss (1.7 ± 0.2 vs. 2.3 ± 0.1 mm, P < 0.01) in 17β-E-treated vessels compared to control-vehicle treated. Histological analyses showed a reduction of stenosis (51.49 ± 6.75 vs.70.86 ± 6.24%, P < 0.05), mean neointimal thickness (0.51 ± 0.07 vs.0.83 ± 0.14 mm, P < 0.05) and inflammation score (1.29 ± 0.28 vs. 2.85 ± 0.40, P < 0.05) in 17β-E-treated arteries compared to control-vehicle treated arteries. Immunohistochemistry analyses revealed a reduction of proliferating smooth muscle cells and increased in-stent reendothelialization in 17β-E-treated arteries. Finally, we observed a correlation between neointimal hyperplasia and inflammation score, which in turn, was inversely related to reendothelialization. Locally delivered, 17β-E is inhibiting the inflammatory response and smooth muscle cells proliferation and improving vascular reendothelialization which together are contributing to reduce instent restenosis in a porcine coronary injury model. Together, these data demonstrate the potential clinical application of 17β-estradiol to improve vascular healing and prevent in-stent restenosis.
Differential gene expression in activated monocyte-derived macrophages following binding of factor VIIa to tissue factor
Authors: Muth Heidrun , Kreis Ingo , Zimmermann Rene , Tillmanns Harald , Hölschermann Hans
Published: October 2005

Factor VIIa/tissue factor (FVIIa/TF) interaction has been reported to induce intracellular signalling in cells constitutively expressing TF, independently of downstream activation of the coagulation cascade. It is unknown, however, whether binding of FVII to its cofactor TF alters the gene expression profile in cells which inducible express TF under inflammatory conditions. To address this issue, gene expression patterns in cultured LPSstimulated monocyte-derived macrophages with or without exposure to FVIIa were compared by cDNA macro-array analysis. Of the 1176 genes examined on the array, a small set of six genes (IL-6, IL-8, TNF-a, GRO-beta alpha-thymosin, cathepsin H) were consistently up-regulated and one gene suppressed (alpha-antitrypsin) in response to FVIIa in activated monocyte-derived macrophages. Among the seven genes identified by array analysis, five genes were finally confirmed by real-time RT-PCR. Interestingly, all of these genes differentially regulated in response to FVIIa (GRO-beta, IL-6, IL-8, TNF-α and alpha-antitrypsin) are critical in inflammation. The changes in gene expression were reflected by corresponding changes in the protein concentrations of IL-6 and IL-8 as demonstrated by ELISA. Active site-inhibited FVIIa had no effect on gene expression indicating that FVIIa-induced gene alteration is dependent on the proteolytic activity of FVIIa. The FVIIa-induced alterations in gene expression were found to be TF-dependent but independent of downstream coagulation proteins like thrombin and FXa. In summary, this study demonstrates that binding of FVIIa to its cofactor TF enhances restricted pro-inflammatory genes in activated monocyte-derived macrophages. By up-regulation of chemokines critical for leukocyte recruitment, FVIIa/TF interaction on activated monocyte- derived macrophages could be relevant to prepare monocytes/ macrophages for extravasation and may represent a novel amplification loop of leukocyte recruitment.
Expressed isolated integrin β1 subunit cytodomain induces endothelial cell death secondary to detachment
Authors: Alghisi Gian , Bamat Jeannine , Ponsonnet Lionel , Bieler Grégory , Bonnard Claude , Hasmim Meriem , Vassalli Giuseppe , Paroz Cécile , Oguey Delphine , Rüegg Curzio
Published: October 2005

Expression of isolated β integrin cytoplasmic domains in cultured endothelial cells was reported to induce cell detachment and death. To test whether cell death was the cause or the consequence of cell detachment, we expressed isolated integrin β1 cytoplasmic and transmembrane domains (CH1) in cultured human umbilical vein endothelial cells (HUVEC), and monitored detachment, viability, caspase activation and signaling. CH1 expression induced dose-dependent cell detachment. At 24 h over 90% of CH1-expressing HUVEC were detached but largely viable (>85%). No evidence of pro-caspase-8, –3, and PARP cleavage or suppression of phosphorylation of ERK, PKB and Iκ-B was observed. The caspase inhibitor z-VAD did not prevent cell detachment. At 48 h, however, CH1-expressing cells were over 50% dead. As a comparison trypsin-mediated detachment resulted in a time-dependent cell death, paralleled by caspase-3 activation and suppression of ERK, PKB and Iκ-B phosphoyrylation at 24 h or later after detachment. HUVEC stimulation with agents that strengthen integrin-mediated adhesion (i.e.PMA, the Src inhibitor PP2 and COMP-Ang1) did not prevent CH1-induced detachment. Expression of CH1 in rat carotid artery endothelial cells in vivo caused endothelial cell detachment and increased nuclear DNA fragmentation among detached cells. A construct lacking the integrin cytoplasmic domain (CH2) had no effect on adhesion and cell viability in vitro and in vivo. These results demonstrate that isolated β1 cytoplasmic domain expression induces caspase-independent detachment of viable endothelial cells and that death is secondary to detachment (i.e. anoikis). They also reveal an essential role for integrins in the adhesion and survival of quiescent endothelial cells in vivo.
Shiga toxin 2 and lipopolysaccharide cause monocytic THP-1 cells to release factors which activate platelet function
Authors: Guessous Fadila , Polanowska-Grabowska Renata , Keepers Tiffany , Obrig Tom , Gear Adrian , Marcinkiewicz Marek
Published: October 2005

Platelet and monocyte activation may contribute to hemolytic anemia, thrombocytopenia and renal failure associated with the hemolytic uremic syndrome (HUS) caused by Escherichia coli O157:H7. Since Shiga toxins (Stxs) and lipopolysaccharide (LPS) from this bacterium are implicated in the pathogenesis of HUS, we examined whether stimulation of THP-1 human monocytic cells by Shiga toxin 2 (Stx2) and LPS can lead to the activation of platelet function. We now show that Stx2 caused THP-1 cells to release the chemokines IL-8, MDC, and RANTES and that the presence of LPS further stimulated this release. IL-8 was produced in greatest amount and was an effective co-agonist for inducing platelet aggregation. Primary human monocytes also released large amounts of IL-8 in response to LPS and Stx2. Factors released by THP-1 cells exposed to Stx2 and LPS activated platelet function as evidenced by increased aggregation, serotonin secretion, P-selectin exposure and by the formation of stable platelet-monocyte aggregates. Our data therefore show that monocytes exposed to E. coli-derived Stx2 and LPS release factors which activate platelet function.
Understanding platelets
Authors: Dittrich Marcus , Birschmann Ingvild , Stuhlfelder Christiane , Sickmann Albert , Herterich Sabine , Nieswandt Bernhard , Walter Ulrich , Dandekar Thomas
Published: October 2005

New large-scale analysis techniques such as bioinformatics, mass spectrometry and SAGE data analysis will allow a new framework for understanding platelets. This review analyses some important options and tasks for these tools and examines an outline of the new, refined picture of the platelet outlined by these new techniques. Looking at the platelet-specific building blocks of genome, (active) transcriptome and proteome (notably secretome and phospho-proteome), we summarize current bioinformatical and biochemical approaches, tasks as well as their limitations. Understanding the surprisingly complex platelet regarding compartmentalization, key cascades, and pathways including clinical implications will remain an exciting and hopefully fruitful challenge for the future.