bluuebunny/crossref_metadata_2025 huggingface dataset:
An intronic single base exchange leads to a brown adipose tissue-specific loss of Ucp3 expression and an altered body mass trajectory
Authors: Fromme Tobias , Hoffmann Christoph , Nau Kerstin , Rozman Jan , Reichwald Kathrin , Utting Michael , Platzer Matthias , Klingenspor Martin
Published: April 2009

Uncoupling protein 3 (Ucp3) is a transport protein of the inner mitochondrial membrane and presumably is implicated in the maintenance or tolerance of high lipid oxidation rates. Ucp3 is predominantly expressed in skeletal muscle and brown adipose tissue and is regulated by a transcription factor complex involving peroxisome proliferator-activated receptor-α, MyoD, and COUP transcription factor II. By analysis of a mutant Djungarian hamster model lacking Ucp3 transcription specifically in brown adipose tissue, we identified a putative transcription factor-binding site that confers tissue specificity. A naturally occurring intronic point mutation disrupting this site leads to brown adipose tissue-specific loss of Ucp3 expression and an altered body weight trajectory. Our findings provide insight into tissue-specific Ucp3 regulation and, for the first time, unambiguously demonstrate that changes in Ucp3 expression can interfere with body weight regulation.
Genetic locus on rat chromosome 20 regulates diet-induced adipocyte hypertrophy: a microarray gene expression study
Authors: Bourdon Céline , Hojna Silvie , Jordan Melissa , Bérubé Julie , Křen Vladimír , Pravenec Michal , Liu Peter , Arab Sara , Pausová Zdenka
Published: April 2009

Obesity is a leading cause of diabetes mellitus and hypertension. Molecular signals produced by adipose tissue may contribute to the pathogenesis of these two disorders. We showed previously that a specific segment of rat chromosome 20 (RNO20) contains a gene(s) regulating the degree of obesity, glucose intolerance, and hypertension in response to a chronic high-fat diet (HFD). Here we examined microarray gene expression profiles and cellular morphology of adipose tissues and whole body energy expenditure in this model. Adult male spontaneously hypertensive rats (SHR) and a congenic strain (SHR.1N) that differs from SHR by the above-mentioned segment of RNO20 were fed for 12 wk with HFD or a normal diet. At the end of this period, whole body energy expenditure was measured with indirect calorimetry. In response to HFD, body weight, fat pad weights, adipocyte size, and serum leptin levels increased significantly more in SHR.1N than SHR. Microarray gene expression profiles [Affymetrix, 15,923 genes and expressed sequence tags (ESTs)] showed that multiple genes of molecular pathways involved in lipogenesis were downregulated to a similar level in both strains, whereas genes involved in fatty acid oxidation and energy dissipation were upregulated less in SHR.1N than SHR. This was associated with lower whole body energy expenditure in SHR.1N than SHR at the end of the 12-wk HFD. Our results suggest that a gene(s) within the RNO20 segment regulate(s) HFD-induced increases in adiposity, and that this effect may be mediated, at least in part, by the impact of that gene(s) on fat burning and energy expenditure.
Evaluation and Management of Patients with Noncardiac Chest Pain
Authors: Shekhar C. , Whorwell P. J.
Published: April 2009

Up to a third of patients undergoing coronary angiography for angina-like chest pain are found to have normal coronary arteries and a substantial proportion of these individuals continue to consult and even attend emergency departments. Initially, these patients are usually seen by cardiologists but with accumulating evidence that the pain might have a gastrointestinal origin, it may be more appropriate for them to be cared for by the gastroenterologist once a cardiological cause has been excluded. This review covers the assessment and management of this challenging condition, which includes a combination of education, reassurance, and pharmacotherapy. For the more refractory cases, behavioral treatments, such as cognitive behavioral therapy or hypnotherapy, may have to be considered.
Simulation of Inhomogeneous Columns of Beads under Vertical Vibration
Authors: Carneiro Marcus V. , Barroso Joaquim J. , Macau Elbert E. N.
Published: April 2009

We present results from computational experiments of one‐dimensional inhomogeneous granular
column. With characteristic properties lying between those of liquids and solids, this class of material
consists of assemblies of solid particles which interact via mechanical forces (contact and friction)
and are maintained together by a gravitational field. The system is composed of a vertical column
of spherical beads driven by a sinusoidally vibrating plate. Results for 10 bead experiments show
the fluidization and condensation phenomena, both dependent on the amplitude and frequency of
the driving plate. Some scaling properties arising from the dynamics of the beads are also shown.
What Horses and Humans See: A Comparative Review
Authors: Murphy Jack , Hall Carol , Arkins Sean
Published: April 2009

Adaptations of the mammalian eye have tailored each to its own particular ecological niche. On the one hand, it would appear that the horse is best served by a system that can keep “half an eye” on everything, while the human benefits from focussing on more specific aspects of the visual array. By adapting a range of techniques, originally used to assess human visual ability, it has been possible to compare the human visual experience with that of the horse. In general, the results of the majority of these comparative studies indicate that the visual capabilities of the horse are broadly inferior to the human equivalents in acuity, accommodation, and colour vision. However, both the horse and human abilities to judge distance and depth perception may be quite comparable while equine vision is certainly superior to that of human's under scotopic conditions. Individual variation in visual ability, which is routinely taken for granted in humans, is also likely to occur in the horse. Such variation would undoubtedly affect equine performance, particularly in terms of expectation of athletic competitive outcomes in modern equitation. In addition to such considerations as conformation and athletic ability, a detailed assessment of the visual ability might contribute to a more accurate prediction of future performance characteristics in the horse. Although further investigation is required in order to appreciate fully both the capabilities and limitations of the equine visual system, the information currently available should now be considered and applied more rigorously both in the design of the equine environment and in the implementation of contemporary equine training methods. This need is the greatest in areas of equestrian sport where the outcomes of either or both equine and human visual judgements can be critical, the cost of failure often high and occasionally results in fatal consequences for both parties of the horse-human dyad.
Kit Inhibitor APcK110 Induces Apoptosis and Inhibits Proliferation of Acute Myeloid Leukemia Cells
Authors: Faderl Stefan , Pal Ashutosh , Bornmann William , Albitar Maher , Maxwell David , Van Quin , Peng Zhenghong , Harris David , Liu Zhiming , Hazan-Halevy Inbal , Kantarjian Hagop M. , Estrov Zeev
Published: April 2009

Kit is a membrane-bound tyrosine kinase and receptor for stem cell factor (SCF) with a crucial role in hematopoiesis. Mutations of KIT occur in almost half of patients with core-binding factor leukemias, in which they have been associated with worse outcome. Development of new compounds targeting Kit may therefore hold promise for therapy. We investigated the activity and mechanism of action of APcK110, a novel Kit inhibitor, in the mastocytosis cell line HMC1.2 (KITV560G and KITD816V), acute myeloid leukemia (AML) lines OCIM2 and OCI/AML3 (both wild-type), and primary samples from patients with AML. We show that (a) APcK110 inhibits proliferation of the mastocytosis cell line HMC1.2 and the SCF-responsive cell line OCI/AML3 in a dose-dependent manner; (b) APcK110 is a more potent inhibitor of OCI/AML3 proliferation than the clinically used Kit inhibitors imatinib and dasatinib and at least as potent as cytarabine; (c) APcK110 inhibits the phosphorylation of Kit, Stat3, Stat5, and Akt in a dose-dependent fashion, showing activity of APcK110 on Kit and its downstream signaling pathways; (d) APcK110 induces apoptosis by cleavage of caspase-3 and poly(ADP-ribose) polymerase; and (e) APcK110 inhibits proliferation of primary AML blasts in a clonogenic assay but does not affect proliferation of normal colony-forming cells. Although APcK110 activity may partly depend on cytokine responsiveness (e.g., SCF) and not exclusively KIT mutation status, it remains a potent inhibitor of AML and mastocytosis cell lines and primary AML samples. APcK110 and similar compounds should be evaluated in clinical trials of patients with AML. [Cancer Res 2009;69(9):3910–7]
Synergistic Activity of the Src Family Kinase Inhibitor Dasatinib and Oxaliplatin in Colon Carcinoma Cells Is Mediated by Oxidative Stress
Authors: Kopetz Scott , Lesslie Donald P. , Dallas Nikolas A. , Park Serk I. , Johnson Marjorie , Parikh Nila U. , Kim Michael P. , Abbruzzese James L. , Ellis Lee M. , Chandra Joya , Gallick Gary E.
Published: April 2009

Chemotherapeutic regimens for the treatment of colorectal cancer generally include oxaliplatin, although inherent and acquired resistance is common. One potential mediator of oxaliplatin sensitivity is the nonreceptor protein tyrosine kinase, Src, the activity of which correlates with disease stage and patient survival. Therefore, we investigated the effects of Src inhibition using the tyrosine kinase inhibitor dasatinib on oxaliplatin sensitivity. We show that oxaliplatin acutely activates Src and that combination treatment with dasatinib is synergistic in a cell-line dependent manner, with the level of Src activation correlating with extent of synergy in a panel of six cell lines. Intracellular reactive oxygen species (ROS) are generated after oxaliplatin treatment, and ROS potently activates Src. Pretreatment with antioxidants inhibits oxaliplatin-induced Src activation. In oxaliplatin-resistant cell lines, Src activity is constitutively increased. In a mouse model of colorectal liver metastases, treatment with oxaliplatin also results in chronic Src activation. The combination of dasatinib and oxaliplatin results in significantly smaller tumors compared with single-agent treatment, corresponding with reduced proliferation and angiogenesis. Therefore, we conclude that oxaliplatin activates Src through a ROS-dependent mechanism. Src inhibition increases oxaliplatin activity both in vitro and in vivo. These results suggest that Src inhibitors combined with oxaliplatin may have efficacy in metastatic colon cancer and may provide the first indication of a molecular phenotype that might be susceptible to such combinations. [Cancer Res 2009;69(9):3842–9]
Poly(ADP-Ribose) Polymerase-1 Inhibitor Treatment Regresses Autochthonous Brca2/p53-Mutant Mammary Tumors In vivo and Delays Tumor Relapse in Combination with Carboplatin
Authors: Hay Trevor , Matthews James R. , Pietzka Lucie , Lau Alan , Cranston Aaron , Nygren Anders O.H. , Douglas-Jones Anthony , Smith Graeme C.M. , Martin Niall M.B. , O’Connor Mark , Clarke Alan R.
Published: April 2009

Germ-line heterozygosity of the BRCA2 gene in women predisposes to breast and ovarian cancers. Successful therapies targeted specifically at these neoplasms have thus far remained elusive. Recent studies in mice have shown that inhibition of poly(ADP-ribose) polymerase-1 (PARP-1) targets cells lacking Brca2 and xenografts derived from BRCA2-deficient ES cells or Chinese hamster ovary cells. We set out to develop a more relevant preclinical model that will inform and accelerate translation into the clinic. As such, we conditionally deleted Brca2 and p53 within murine mammary epithelium and treated the resulting tumors in situ with a highly potent PARP-1 inhibitor (AZD2281) alone or in combination with carboplatin. Daily exposure to AZD2281 for 28 days caused significant regression or growth inhibition in 46 of 52 tumors. This response was shown to be specific to tumors lacking both Brca2and p53. AZD2281/carboplatin combination therapy for 28 days showed no advantage over carboplatin monotherapy. However, if PARP inhibitor treatment was continued, this significantly increased the time to tumor relapse and death in these mice. This preclinical study is the first to show in vivo hypersensitivity of spontaneously arising Brca2-deficient mammary tumors to PARP-1 inhibition monotherapy or combination therapy. As such, our data add substantial weight to the argument for the use of PARP inhibitors as therapeutic agents against human breast cancers in which BRCA2 is mutated. Moreover, the specificity that we have shown further suggests that PARP inhibitors will be generally effective against tumors caused by dysregulation of components of the homologous recombination pathway. [Cancer Res 2009;69(9):3850–55]
Prevention of Spontaneous Tumor Development in aretTransgenic Mouse Model by Ret Peptide Vaccination with Indoleamine 2,3-Dioxygenase Inhibitor 1-Methyl Tryptophan
Authors: Zeng Jun , Cai Shaohui , Yi Yanmei , He Yuwen , Wang Zhen , Jiang Guangmin , Li Xiaokun , Du Jun
Published: April 2009

The present study investigated an immunotherapeutic strategy for rearranged during transfection proto-oncogene (ret)–associated carcinomas in a transgenic MT/ret 304/B6 mouse model in which spontaneous tumors develop due to overexpression of the ret gene. A Ret peptide vaccine comprising an extracellular fragment of Ret protein and Th1-polarized immunoregulator CpG oligonucleotide (1826) induced strong and specific cellular and humoral immune responses in wild-type C57BL/6 mice, showing that the Ret peptide has a strong immunogenic potential as part of an antitumor vaccine. In MT/ret 304/B6 mice, however, the vaccine was only modestly effective as an inducer of the humoral immune response, and it failed to elicit a T-cell response. An immunohistochemical analysis revealed marked indoleamine 2,3-dioxygenase expression after immunization with Ret peptide vaccine in the lymph nodes and spleens of MT/ret 304/B6 mice. The systemic administration of the potent inhibitor of indoleamine 2,3-dioxygenase 1-methyl tryptophan (1MT) along with Ret vaccine produced a significant increase in tumor-specific cytotoxic activity. A delay in spontaneous tumor development was also observed in the MT/ret 304/B6 mice to which the Ret vaccine and 1MT were administered. These results indicate that an improved Ret vaccine composed of Ret peptide plus CpG oligonucleotide plus 1MT is a potential therapeutic strategy for treatment of ret-associated carcinomas. [Cancer Res 2009;69(9):3963–70]
Species-Specific In vivo Engraftment of the Human BL Melanoma Cell Line Results in an Invasive Dedifferentiated Phenotype Not Present in Xenografts
Authors: Cedervall Jessica , Jamil Seema , Prasmickaite Lina , Cheng YenFu , Eskandarpour Malihe , Hansson Johan , Mælandsmo Gunhild M. , Ringborg Ulrik , Gulyas Miklos , Zhen He Suo , Kanter Lena , Ährlund-Richter Lars
Published: April 2009

For clinically relevant studies on melanoma progression and invasiveness, in vivo experimental systems with a human cellular microenvironment would be advantageous. We have compared tumor formation from a human cutaneous malignant melanoma cell line (BL), after injection as conventional xenografts in the mouse, or when injected into a predominantly species-specific environment of human embryonic stem cell–derived teratoma induced in the mouse (the hEST model). The resulting melanoma histology was generally analogous, both systems showing delimited densely packed areas with pleomorphic cells of malignant appearance. A specificity of the integration process into the human embryonic teratoma tissues was indicated by the melanoma exclusively being found in areas compatible with condensed mesenchyme, similar to neural crest development. Here, also enhanced neovascularization was seen within the human mesenchymal tissues facing the BL melanoma growth. Furthermore, in the hEST model an additional melanoma cell phenotype occurred, located at the border of, or infiltrating into, the surrounding human loose mesenchymal fibrous stroma. This BL population had a desmoplastic spindle-like appearance, with markers indicative of dedifferentiation and migration. The appearance of this apparently more aggressive phenotype, as well as the induction of human angiogenesis, shows specific interactions with the human embryonic microenvironment in the hEST model. In conclusion, these data provide exciting options for using the hEST model in molecular in vivo studies on differentiation, invasiveness, and malignancy of human melanoma, while analyzing species-specific reactions in vivo. [Cancer Res 2009;69(9):3746–54]
Caspase-8 Association with the Focal Adhesion Complex Promotes Tumor Cell Migration and Metastasis
Authors: Barbero Simone , Mielgo Ainhoa , Torres Vicente , Teitz Tal , Shields David J. , Mikolon David , Bogyo Matthew , Barilà Daniela , Lahti Jill M. , Schlaepfer David , Stupack Dwayne G.
Published: April 2009

Caspase-8 is a proapoptotic protease that suppresses neuroblastoma metastasis by inducing programmed cell death. Paradoxically, caspase-8 can also promote cell migration among nonapoptotic cells; here, we show that caspase-8 can promote metastasis when apoptosis is compromised. Migration is enhanced by caspase-8 recruitment to the cellular migration machinery following integrin ligation. Caspase-8 catalytic activity is not required for caspase-8–enhanced cell migration; rather, caspase-8 interacts with a multiprotein complex that can include focal adhesion kinase and calpain 2 (CPN2), enhancing cleavage of focal adhesion substrates and cell migration. Caspase-8 association with CPN2/calpastatin disrupts calpastatin-mediated inhibition of CPN2. In vivo, knockdown of either caspase-8 or CPN2 disrupts metastasis among apoptosis-resistant tumors. This unexpected molecular collaboration provides an explanation for the continued or elevated expression of caspase-8 observed in many tumors. [Cancer Res 2009;69(9):3755–63]
B-MYB Is Required for Recovery from the DNA Damage–Induced G2 Checkpoint in p53 Mutant Cells
Authors: Mannefeld Mirijam , Klassen Elena , Gaubatz Stefan
Published: April 2009

In response to DNA damage, several signaling pathways that arrest the cell cycle in G1 and G2 are activated. The down-regulation of mitotic genes contributes to the stable maintenance of the G2 arrest. The human LINC or DREAM complex, together with the B-MYB transcription factor, plays an essential role in the expression of G2-M genes. Here, we show that DNA damage results in the p53-dependent binding of p130 and E2F4 to LINC and the dissociation of B-MYB from LINC. We find that B-MYB fails to dissociate from LINC in p53 mutant cells, that this contributes to increased G2-M gene expression in response to DNA damage in these cells, and, importantly, that B-MYB is required for recovery from the G2 DNA damage checkpoint in p53-negative cells. Reanalysis of microarray expression data sets revealed that high levels of B-MYB correlate with a p53 mutant status and an advanced tumor stage in primary human breast cancer. Taken together, these data suggest that B-MYB/LINC plays an important role in the DNA damage response downstream of p53. [Cancer Res 2009;69(9):4073–80]
Catecholamines Regulate Tumor Angiogenesis
Authors: Chakroborty Debanjan , Sarkar Chandrani , Basu Biswarup , Dasgupta Partha Sarathi , Basu Sujit
Published: April 2009

Among the regulators of angiogenesis, catecholamine neurotransmitters are of recent interest because of their opposite roles in the regulation of tumor neovascularization. Norepinephrine and epinephrine by acting through specific adrenoceptors increase the synthesis of proangiogenic factors, and thereby, promote tumor growth. In contrast, dopamine acting via its specific D2 receptors inhibits tumor growth by suppressing the actions of vascular permeability factor/vascular endothelial growth factor-A on both tumor endothelial and bone marrow-derived endothelial progenitor cells. These reports identify novel endogenous regulators of tumor angiogenesis and also indicate a new and an inexpensive class of antiangiogenic drugs for the treatment of cancer. [Cancer Res 2009;69(9):3727–30]
Wnt/β-Catenin Signaling Regulates Cytokine-Induced Human Inducible Nitric Oxide Synthase Expression by Inhibiting Nuclear Factor-κB Activation in Cancer Cells
Authors: Du Qiang , Zhang Xinglu , Cardinal Jon , Cao Zongxian , Guo Zhong , Shao Lifang , Geller David A.
Published: April 2009

The human inducible nitric oxide synthase (hiNOS) gene is regulated by nuclear factor κB (NF-κB) and has recently been shown to be a target of the Wnt/β-catenin pathway. In this study, we tested the hypothesis that Wnt/β-catenin signaling might regulate cytokine- or tumor necrosis factor α (TNFα)–induced hiNOS expression through interaction with NF-κB. A cytokine mixture of TNFα + interleukin (IL)-1β + IFNγ induced a 2- to 3-fold increase in hiNOS promoter activity in HCT116 and DLD1 colon cells, but produced a 2-fold decrease in SW480 colon cancer cells. A similar differential activity was seen in liver cancer cells (HepG2, Huh7, and Hep3B). Overexpression of β-catenin produced a dose-dependent decrease in NF-κB reporter activity and decreased cytokine mixture–induced hiNOS promoter activity. Gel shift for TNFα-induced hiNOS NF-κB activation showed decreased p50 binding and decreased NF-κB reporter activity in the β-catenin–mutant HAβ18 cells. Conversely, enhanced p50 binding and increased NF-κB reporter activity were seen in HAβ85 cells, which lack β-catenin signaling. Coimmunoprecipitation confirmed that β-catenin complexed with both p65 and p50 NF-κB proteins. NF-κB–dependent Traf1 protein expression also inversely correlated with the level of β-catenin. Furthermore, SW480 cells stably transformed with wild-type adenomatous polyposis coli showed decreased β-catenin protein and increased TNFα-induced p65 NF-κB binding as well as iNOS and Traf1 expression. Finally, β-catenin inversely correlated with iNOS and Fas expression in vivo in hepatocellular carcinoma tumor samples. Our in vitro and in vivo data show that β-catenin signaling inversely correlates with cytokine-induced hiNOS and other NF-κB–dependent gene expression. These findings underscore the complex role of Wnt/β-catenin, NF-κB, and iNOS signaling in the pathophysiology of inflammation-associated carcinogenesis. [Cancer Res 2009;69(9):3764–71]
When the Sphingosine Kinase 1/Sphingosine 1-Phosphate Pathway Meets Hypoxia Signaling: New Targets for Cancer Therapy
Authors: Ader Isabelle , Malavaud Bernard , Cuvillier Olivier
Published: April 2009

The reduction in the normal level of tissue oxygen tension or hypoxia is a characteristic of solid tumors that triggers the activation of signaling pathways promoting neovascularization, metastasis, increased tumor growth, and resistance to treatments. The activation of the transcription factor hypoxia-inducible factor 1α (HIF-1α) has been identified as the master mechanism of adaptation to hypoxia. In a recent study, we identified the sphingosine kinase 1/sphingosine 1-phosphate (SphK1/S1P) pathway, which elicits various cellular processes including cell proliferation, cell survival, or angiogenesis, as a new modulator of HIF-1α activity under hypoxic conditions. Here, we consider how the SphK1/S1P signaling pathway could represent a very important target for therapeutic intervention in cancer. [Cancer Res 2009;69(9):3723–6]
Mutations in the Hepatitis C Virus core Gene Are Associated with Advanced Liver Disease and Hepatocellular Carcinoma
Authors: Fishman Sarah L. , Factor Stephanie H. , Balestrieri Cinzia , Fan Xiaofeng , DiBisceglie Adrian M. , Desai Suresh M. , Benson Gary , Branch Andrea D.
Published: April 2009

Purpose: Hepatitis C virus (HCV) infection can promote the development of hepatocellular carcinoma (HCC). Published data implicate the HCV core gene in oncogenesis. We tested the hypothesis that core gene sequences from HCC patients differ from those of patients without cirrhosis/HCC.

Experimental Design: Full-length HCV sequences from HCC patients and controls were obtained from the investigators and GenBank and compared with each other. A logistic regression model was developed to predict the HCC risk of individual point mutations and other sequence features. Mutations in partial sequences (bases 36-288) from HCC patients and controls were also analyzed. The first base of the AUG start codon was designated position 1.

Results: A logistic regression model developed through analysis of full-length core gene sequences identified seven polymorphisms significantly associated with increased HCC risk (36G/C, 209A, 271U/C, 309A/C, 435A/C, 481A, and 546A/C) and an interaction term (for 209A-271U/C) that had an odds ratio <1.0. Three of these polymorphisms could be analyzed in the partial sequences. Two of them, 36G/C and 209A, were again associated with increased HCC risk, but 271U/C was not. The odds ratio of 209A-271U/C was not significant.

Conclusions: HCV core genes from patients with and without HCC differ at several positions. Of interest, 209A has been associated with IFN resistance and HCC in previous studies. Our findings suggest that HCV core gene sequence data might provide useful information about HCC risk. Prospective investigation is needed to establish the temporal relationship between appearance of the viral mutations and development of HCC.
Phase I Study of MG98, an Oligonucleotide Antisense Inhibitor of Human DNA Methyltransferase 1, Given as a 7-Day Infusion in Patients with Advanced Solid Tumors
Authors: Plummer Ruth , Vidal Laura , Griffin Melanie , Lesley Mark , de Bono Johann , Coulthard Sally , Sludden Julieann , Siu Lillian L. , Chen Eric X. , Oza Amit M. , Reid Gregory K. , McLeod A. Robert , Besterman Jeffrey M. , Lee Chooi , Judson Ian , Calvert Hilary , Boddy Alan V.
Published: April 2009

Purpose: To assess the safety and tolerability, pharmacokinetics, and early evidence of antitumor activity of escalating doses of MG98, an antisense oligonucleotide to DNA methyltransferase 1 (DNMT1), which has been shown to reduce CpG island methylation and allow reexpression of tumor suppressor genes in vitro.

Experimental Design: In this phase I, open-label study, patients with advanced solid malignancies were treated with escalating doses of MG98 administered as a continuous i.v. infusion over 7 days repeated every 14 days. Cohorts of three patients, which could be expanded to six patients, were studied. The maximum tolerated dose was defined as the highest dose at which no more than 33% of subjects experienced dose-limiting toxicity. Pharmacokinetic and pharmacodynamic parameters of MG98 were also characterized.

Results: Thirty-three patients were treated at doses of 100 to 250 mg/m2/d MG98. MG98 was well tolerated with mild fatigue and myalgia, dose-limiting toxicity was asymptomatic transaminitis, and the maximum tolerated dose was 200 mg/m2/d. One patient achieved a partial response and another prolonged disease stabilization. Plasma half-life of MG98 was short (2 hours), drug concentrations reaching a dose-dependent steady state during infusion with a volume of distribution equivalent to plasma volume. Suppression of DNMT1 expression was observed in 26 of 32 patients studied.

Conclusions: MG98 was well tolerated with early evidence of clinical activity. Proof of mechanism was observed and measurement of DNMT1 expression in peripheral blood mononuclear cells may be useful in future phase II development.
Rectal Mucosal Microvascular Blood Supply Increase Is Associated with Colonic Neoplasia
Authors: Gomes Andrew J. , Roy Hemant K. , Turzhitsky Vladimir , Kim Young , Rogers Jeremy D. , Ruderman Sarah , Stoyneva Valentina , Goldberg Michael J. , Bianchi Laura K. , Yen Eugene , Kromine Alexey , Jameel Mohammed , Backman Vadim
Published: April 2009

Purpose: Endoscopic examination has proven effective in both detecting and preventing colorectal cancer; however, only about a quarter of eligible patients undergo screening. Even if the compliance rate increased, limited endoscopic capacity and cost would be prohibitive. There is a need for an accurate method to target colonoscopy to those most at risk of harboring colonic neoplasia. Exploiting field carcinogenesis seems to be a promising avenue. Our group recently reported that an early increase in blood supply (EIBS) is a reliable marker of field carcinogenesis in experimental models. We now investigate whether in situ detection of EIBS in the rectum can predict neoplasia elsewhere in the colon.

Experimental Design: We developed a novel polarization-gated spectroscopy fiber-optic probe that allows depth-selective interrogation of microvascular blood content. Using the probe, we examined the blood content in vivo from the rectal mucosa of 216 patients undergoing screening colonoscopy.

Results: Microvascular blood content was increased by ∼50% in the endoscopically normal rectal mucosa of patients harboring advanced adenomas when compared with neoplasia-free patients irrespective of lesion location. Demographic factors and nonneoplastic lesions did not confound this observation. Logistic regression using mucosal oxyhemoglobin concentration and patient age resulted in a sensitivity of 83%, a specificity of 82%, and an area under the receiver operating characteristic curve of 0.88 for the detection of advanced adenomas.

Conclusions: Increased microvascular blood supply in the normal rectal mucosa is associated with the presence of clinically significant neoplasia elsewhere in the colon, supporting the development of rectal EIBS as a colon cancer risk-stratification tool.
Utility of p16 Immunohistochemistry for the Identification of Lynch Syndrome
Authors: Payá Artemio , Alenda Cristina , Pérez-Carbonell Lucía , Rojas Estefanía , Soto José-Luis , Guillén Carmen , Castillejo Adela , Barberá Victor M. , Carrato Alfredo , Castells Antoni , Llor Xavier , Andreu Montserrat , Koh Jim , Enders Greg H. , Benlloch Susana , Jover Rodrigo
Published: April 2009

Purpose: Immunohistochemistry for mismatch repair proteins has shown utility in the identification of Lynch syndrome, but majority of tumors with loss of MLH1 expression are due to sporadic hypermethylation of the MLH1 promoter. These tumors can also show epigenetic silencing of other genes, such as p16. The aim of our study is to evaluate the utility of p16 immunohistochemistry in the prediction of MLH1 germline mutations.

Experimental Design: p16 immunohistochemistry was appropriately evaluated in 79 colorectal cancers with loss of MLH1 expression. Methylation of MLH1 and p16 were quantitatively studied using real-time PCR assay Methylight. BRAF V600E mutation in tumor tissue was also investigated. Genetic testing for germline mutation of MLH1 was made on 52 patients.

Results: Loss of p16 expression was seen in 21 of 79 samples (26.6%). There was found statistically significant association between p16 expression and p16 methylation (P < 0.001), MLH1 methylation (P < 0.001), and BRAF mutation (P < 0.005). All tumors with loss of p16 expression showed hypermethylation of p16 (21 of 21), 95.2% (20 of 21) showed MLH1 methylation, and 71.4% (15 of 21) were mutated for BRAF V600E. Mutational analysis showed pathogenic germline mutations in 8 of the patients, harboring 10 tumors. All 10 of these tumors showed normal staining of p16 in the immunochemical analysis.

Conclusions: p16 immunohistochemistry is a good surrogate marker for p16 and MLH1 epigenetic silencing due to hypermethylation, and is useful as screening tool in the selection of patients for genetic testing in Lynch syndrome.
Bortezomib induces schedule-dependent modulation of gemcitabine pharmacokinetics and pharmacodynamics in non-small cell lung cancer and blood mononuclear cells
Authors: Ceresa Cecilia , Giovannetti Elisa , Voortman Jens , Laan Adrie C. , Honeywell Richard , Giaccone Giuseppe , Peters Godefridus J.
Published: April 2009

Bortezomib combination with gemcitabine/cisplatin in patients with advanced tumors, predominantly non-small cell lung cancer (NSCLC), showed an unexpected transient drop in the deoxycytidine plasma levels, a marker for gemcitabine activity. This study investigates the pharmacokinetic/pharmacodynamic effect of bortezomib on gemcitabine in NSCLC and peripheral blood mononuclear cells (PBMC). Gemcitabine metabolites, including difluoro-dCTP (dFdCTP), were studied in PBMCs from bortezomib/gemcitabine/cisplatin-treated patients and from volunteers and NSCLC cells (H460 and SW1573) exposed to 4 h simultaneous or sequential treatments of gemcitabine (50 μmol/L, 4 h) and bortezomib (100 nmol/L, 2 h). Gemcitabine total phosphate levels measured by liquid chromatography-tandem mass spectrometry in PBMCs from bortezomib/gemcitabine/cisplatin-treated patients were strongly reduced after 90 min (−82.2%) up to 4 h post-gemcitabine infusion compared with gemcitabine/cisplatin-treated patients. Accordingly, bortezomib/gemcitabine combinations reduced dFdCTP in PBMCs treated ex vivo. Surprisingly, differential effects were observed in NSCLC cells. dFdCTP decreased after 4 h following gemcitabine removal in H460 but continued to increase for 24 h in SW1573. However, dFdCTP significantly increased (2-fold) in both cell lines in the bortezomib→gemcitabine exposure, coinciding with a major reduction in cell growth compared with single drugs, and the highest increase of deoxycytidine kinase expression, possibly mediated via E2F-1. Bortezomib affects differently gemcitabine pharmacokinetics/pharmacodynamics in PBMCs and NSCLC cells, suggesting that PBMCs are not adequate to evaluate the anticancer activity of bortezomib/gemcitabine combinations. The bortezomib→gemcitabine/cisplatin schedule appeared a safe and active combination for the treatment of advanced NSCLC and the bortezomib→gemcitabine was the most cytotoxic combination in NSCLC cells. The increase of deoxycytidine kinase and dFdCTP might contribute to this synergistic interaction and supports its further clinical investigation. [Mol Cancer Ther 2009;8(5):1026–36]
Electro-Acoustic Stimulation
Authors: McDermott Hugh , Sucher Catherine , Simpson Andrea
Published: April 2009

For simultaneous acoustic and electric stimulation to be perceived as complementary, it may be beneficial for hearing aids and cochlear implants (CI) to be adjusted to provide compatible pitch sensations. To this end, estimates of the pitch perceived for a set of acoustic and electric stimuli were obtained from 14 CI users who had usable low-frequency hearing, either in the non-implanted ear or in both ears. The subjects assigned numerical pitch estimates to each of 5 acoustic pure tones and 5 single-electrode electric pulse trains. On average, the acoustic frequency that corresponded in pitch to stimulation on the most apical electrode was approximately 480 Hz. This was about 1 octave lower than the frequency expected from Greenwood’s frequency-place function applied to estimates of the electrode insertion angle based on X-ray images. Furthermore, evidence was found suggesting that pitch decreased with increasing duration of CI use. Pitch estimates from 5 subjects who completed the experiment before experiencing any other sounds through their CI were generally close to the values expected from a recently published frequency map for the cochlear spiral ganglion. Taken together, these findings suggest that some perceptual adaptation may occur that would compensate in part for the apparent mismatch between the intracochlear position of the electrodes and the acoustic frequencies assigned to them in the sound processor.
How Much Residual Hearing Is ‘Useful’ for Music Perception with Cochlear Implants?
Authors: El Fata Fouad , James Chris J. , Laborde Marie-Laurence , Fraysse Bernard
Published: April 2009

Aim: To compare performance on a song recognition task of bilaterally combined electric and acoustic hearing (bimodal stimulation) with electric or acoustic hearing alone. Methods:Subjects were 14 adults with cochlear implants (CI) who continued to use a hearing aid (HA) in one/both ears. Subjects were asked to identify excerpts from 15 popular songs, which were familiar to them, presented in a random order via a single loudspeaker. Presentation conditions were fixed in order: bimodal, CI alone and then HA alone. Musical excerpts were presented in each condition with and then without lyrics. Results:In a subgroup of subjects (n = 8) with better low-frequency residual hearing (thresholds <85 dB hearing level (HL)), mean scores for bimodal stimulation were significantly greater than for CI alone. In addition, mean ‘no lyrics’ scores for HA alone (59.7%) were significantly greater than for CI alone (38.8%). All of these subjects considered bimodal stimulation to be the most enjoyable way to listen to music. For the remaining subjects (n = 6) there was no benefit from using bimodal stimulation over CI alone, and the majority of these preferred to listen to music using CI alone. Conclusions:Bimodal stimulation provides better perception of popular music, particularly melody recognition, compared to CI alone when low-frequency residual hearing is better than 85 dB HL.
Hybrid 10 Clinical Trial
Authors: Gantz Bruce J. , Hansen Marlan R. , Turner Christopher W. , Oleson Jacob J. , Reiss Lina A. , Parkinson Aaron J.
Published: April 2009

Acoustic plus electric (electric-acoustic) speech processing has been successful in highlighting the important role of articulation information in consonant recognition in those adults that have profound high-frequency hearing loss at frequencies greater than 1500 Hz and less than 60% discrimination scores. Eighty-seven subjects were enrolled in an adult Hybrid multicenter Food and Drug Administration clinical trial. Immediate hearing preservation was accomplished in 85/87 subjects. Over time (3 months to 5 years), some hearing preservation was maintained in 91% of the group. Combined electric-acoustic processing enabled most of this group of volunteers to gain improved speech understanding, compared to their preoperative hearing, with bilateral hearing aids. Most have preservation of low-frequency acoustic hearing within 15 dB of their preoperative pure tone levels. Those with greater losses (>30 dB) also benefited from the combination of electric-acoustic speech processing. Postoperatively, in the electric-acoustic processing condition, loss of low-frequency hearing did not correlate with improvements in speech perception scores in quiet. Sixteen subjects were identified as poor performers in that they did not achieve a significant improvement through electric-acoustic processing. A multiple regression analysis determined that 91% of the variance in the poorly performing group can be explained by the preoperative speech recognition score and duration of deafness. Signal-to-noise ratios for speech understanding in noise improved more than 9 dB in some individuals in the electric-acoustic processing condition. The relation between speech understanding in noise thresholds and residual low-frequency acoustic hearing is significant (r = 0.62; p < 0.05). The data suggest that, in general, the advantages gained for speech recognition in noise by preserving residual hearing exist, unless the hearing loss approaches profound levels. Preservation of residual low-frequency hearing should be considered when expanding candidate selection criteria for standard cochlear implants. Duration of profound high-frequency hearing loss appears to be an important variable when determining selection criteria for the Hybrid implant.
Cytokine Changes and Tryptophan Metabolites in Medication-Naïve and Medication-Free Schizophrenic Patients
Authors: Kim Yong-Ku , Myint Aye-Mu , Verkerk Robert , Scharpe Simon , Steinbusch Harry , Leonard Brian
Published: April 2009

Cytokine imbalances especially between T helper type (Th) 1 and Th2 and tryptophan breakdown were reported to be involved in the pathophysiology of schizophrenia. The hyperactive inflammatory response system could induce enhanced tryptophan breakdown. This study aimed to investigate the relationship between cytokine changes, tryptophan breakdown parameter changes and clinical parameters in patients with schizophrenia in comparison with normal controls. In the plasma of schizophrenic patients, Th1-specific interferon-γ was significantly higher (F = 7.485, p = 0.007) and Th2-specific interleukin (IL)-4 was significantly lower (F = 126.327, p < 0.0001). The Th1-related cytokine IL-2 was lower (F = 5.409, p = 0.021) but tumor necrosis factor-α (TNF-α) and Th2-related IL-6 were higher (F = 95.004, p < 0.0001 and F = 408.176, p < 0.0001, respectively) in the plasma of schizophrenic patients. After 6 weeks of treatment, IL-6 and TNF-α were significantly reduced (t = –3.762, p < 0.0001 and z = –2.668, p = 0.008). At the time of admission, plasma tryptophan concentrations were lower (F = 6.339, p = 0.012) in schizophrenic patients and were negatively correlated with the total positive symptoms score (r2 = -0.343, p = 0.004). After 6 weeks of medication, both plasma tryptophan and kynurenine concentrations were increased (t = –2.937, p = 0.005 and t = –3.214, p = 0.002, respectively). The findings of this study indicate a hyperactive pro-inflammatory response inducing a change in tryptophan metabolism that might be related to the development of positive symptoms in schizophrenia.
Ligasure Vessel Sealing System versus Harmonic Scalpel for Sutureless Nonanatomical Pulmonary Resections in a Rabbit Model
Authors: Cakan A. , Yoldas B. , Samancilar O. , Ertugrul V. , Turhan K. , Cagirici U. , Askar F. , Veral A.
Published: April 2009

Background: The safety and efficacy of the ligasure vessel sealing system (LVSS) and harmonic scalpel (HS) in sutureless nonanatomical lung resections were evaluated. Methods: On twenty adult rabbit lungs, 1 × 1 cm wedge resections were performed under one-lung ventilation with both LVSS and HS. The air tightness and tissue damage caused by these different techniques were measured and compared. Results: No statistically significant differences were found when the air tightness for both devices was compared after resection (p = 0.37). Tissue damage was obtained for LVSS, and the difference was statistically significant (p < 0.001). Discussion: LVSS and HS can both be used for peripheral lung resections without any need of further intervention for securing the air tightness. LVSS was found safer by means of tissue damage when compared with HS in this experimental study.
The Central Vestibular Complex in Dolphins and Humans: Functional Implications of Deiters’ Nucleus
Authors: Kern A. , Seidel K. , Oelschläger H.H.A.
Published: April 2009

Toothed whales (Odontocetes; e.g., dolphins) are well-known for efficient underwater locomotion and for their acrobatic capabilities. Nevertheless, in relation to other mammals including the human and with respect to body size, their vestibular apparatus is reduced, particularly the semicircular canals. Concomitantly, the vestibular nerve and most of the vestibular nuclei are thin and small, respectively, in comparison with those in terrestrial mammals. In contrast, the lateral (Deiters’) vestibular nucleus is comparatively well developed in both coastal and pelagic dolphins. In the La Plata dolphin (Pontoporia blainvillei) and the Common dolphin (Delphinus delphis), all of the vestibular nuclei are present and their topographic relations are similar to those in humans. Quantitative analysis, however, revealed that in the dolphin most of the nuclei (superior, medial, descending nucleus) are minute both in absolute and relative terms. Here, the only exception is the lateral vestibular nucleus, which is of comparable size in humans and Pontoporia and decidedly more voluminous in Delphinus. While the small size of the majority of the dolphin’s vestibular nuclei correlates well with miniaturization of the semicircular canals, the size of Deiters’ nucleus seems to support its relative independence from the vestibular system and a close functional relationship with the cerebellum. In comparison with findings in humans and other terrestrial mammals, both of these aspects seem to be related to the physical conditions of aquatic life and locomotion in three dimensions.
Brain Size: A Global or Induced Cost of Learning?
Authors: Snell-Rood Emilie C. , Papaj Daniel R. , Gronenberg Wulfila
Published: April 2009

The role of brain size as a cost of learning remains enigmatic; the nature and timing of such costs is particularly uncertain. On one hand, comparative studies suggest that congenitally large brains promote better learning and memory. In that case, brain size exacts a global cost that accrues even if learning does not take place; on the other hand, some developmental studies suggest that brains grow with experience, indicating a cost that is induced when learning occurs. The issue of how costs are incurred is an important one, because global costs are expected to constrain the evolution of learning more than would induced costs. We tested whether brain size represented a global and/or an induced cost of learning in the cabbage white butterfly, Pieris rapae. We assayed the ability of full sibling families to learn to locate either green hosts, for which butterflies have an innate search bias, or red hosts, which are more difficult to learn to locate. Naïve butterflies were sacrificed at emergence and congenital brain volume estimated as a measure of global costs; experienced butterflies were sacrificed after learning and change in brain volume estimated as a measure of induced costs. Only for the mushroom body, a brain region involved in learning and memory in other insects, was volume at emergence related to learning or host-finding. Butterfly families that emerged with relatively larger mushroom bodies showed a greater tendency to improve their ability to find red hosts across the two days of host-search. The volume of most brain regions increased with time in a manner suggesting host experience itself was important: first, total number of landings during host-search was positively related to mushroom body calyx volume, and, second, experience with the red host was positively related to mushroom body lobe volume. At the family level, the relative volume of the mushroom body calyx and antennal lobes following learning was positively related to overall success in finding red hosts. Overall, our results suggest that within species, brain size might act as a small global cost of learning, but that environment-specific changes in brain size might reduce the overall costs of neural tissue in the evolution of learning.
Cisplatin plus Gemcitabine Chemotherapy in Taxane/Anthracycline-Resistant Metastatic Breast Cancer
Authors: Somali Isıl , Alacacioglu Ahmet , Tarhan Mustafa Oktay , Meydan Nezih , Erten Cigdem , Usalp Songul , Yilmaz Ugur
Published: April 2009

Background: The most commonly used chemotherapeutic regimens in the treatment of metastatic breast cancer (MBC) include anthracyclines and taxanes. In our study, we investigated the efficacy and tolerability of cisplatin plus gemcitabine combination chemotherapy regimen in patients with MBC, who exhibited disease progression after anthracycline- and taxane-based chemotherapy. Methods: Thirty-three patients with taxane/anthracycline-resistant MBC have been treated with gemcitabine 1,000 mg/m2 intravenously and cisplatin 30 mg/m2 intravenously on days 1 and 8 of a 3-week treatment cycle. Results: Thirty-one patients were assessable for response. One of the 31 patients (3.2%) showed complete response, while 7 patients (22.6%) showed partial response; the objective response rate was 25.8%. Stable and progressive disease was observed in 6 (19.4%) and 17 patients (54.8%), respectively. The median time to progression was 4 months (95% CI 2.15–5.85). The median survival time of all patients was 9.5 months (95% CI 7.86–11.14). Conclusion: Gemcitabine and cisplatin combination therapy is moderately active and safe in patients with MBC previously treated with anthracycline and taxanes.