bluuebunny/crossref_metadata_2025 huggingface dataset:
Antitumoral Immune Response by Recruitment and Expansion of Dendritic Cells in Tumors Infected with Telomerase-Dependent Oncolytic Viruses
Authors: Ramakrishna Edukulla , Woller Norman , Mundt Bettina , Knocke Sarah , Gürlevik Engin , Saborowski Michael , Malek Nisar , Manns Michael P. , Wirth Thomas , Kühnel Florian , Kubicka Stefan
Published: February 2009

Virotherapy can potentially be used to induce tumor-specific immune responses and to overcome tumor-mediated tolerance mechanisms because apoptotic tumor cells are exposed together with viral danger signals during oncolysis. However, insufficient numbers of dendritic cells (DC) present at the site of oncolysis can limit a tumor-specific immune response and the resulting therapeutic benefit. We investigated MHC class I peptide–specific immune responses against model antigens ovalbumin (OVA) and hemagglutinin (HA) in mouse tumor models that support efficient replication of the oncolytic adenovirus hTert-Ad. Virotherapy resulted in peptide-specific cytotoxic T-cell responses against intracellular tumor antigens. Triggering of DC and T-cell infiltration to the oncolytic tumors by macrophage inflammatory protein 1α (MIP-1α, CCL3) and Fms-like tyrosine kinase-3 ligand (Flt3L) enhanced both antitumoral and antiviral immune responses. Although immune-mediated clearance of the virus can restrict therapeutic efficacy of virotherapy, MIP-1α/FLT3L–augmented hTert-Ad virotherapy inhibited local tumor growth more effectively than virotherapy alone. In agreement with the hypothesis that immune-mediated mechanisms account for improved outcome in MIP-1α/FLT3L virotherapy, we observed systemic antitumoral effects by MIP-1α/FLT3L virotherapy on uninfected lung metastasis in immunocompetent mice but not in nude mice. Furthermore, MIP-1α/FLT3L virotherapy of primary tumors was strongly synergistic with tumor DC vaccination in inhibition of established lung metastasis. Combined viroimmunotherapy resulted in long-term survival of 50% of treated animals. In summary, improvement of cross-presentation of tumor antigens by triggering of DC and T-cell infiltration during virotherapy enhances antitumoral immune response that facilitates an effective viroimmunotherapy of primary tumors and established metastases. [Cancer Res 2009;69(4):1448–58]
Epidermal Growth Factor Receptor Signaling Synergizes with Hedgehog/GLI in Oncogenic Transformation via Activation of the MEK/ERK/JUN Pathway
Authors: Schnidar Harald , Eberl Markus , Klingler Stefan , Mangelberger Doris , Kasper Maria , Hauser-Kronberger Cornelia , Regl Gerhard , Kroismayr Renate , Moriggl Richard , Sibilia Maria , Aberger Fritz
Published: February 2009

Persistent activation of the Hedgehog (HH)/GLI signaling pathway has been implicated in the development of a number of human cancers. The GLI zinc finger transcription factors act at the end of the HH signaling cascade to control gene expression, and recent studies have shown that the activity of GLI proteins can be additionally modified by integration of distinct signals, such as the MEK/extracellular signal-regulated kinase (ERK) and phosphinositide-3 kinase (PI3K)/AKT pathway. However, little is known about the identity of the upstream activators of these HH/GLI interacting signaling pathways in cancer. Here, we provide evidence that integration of the HH/GLI and epidermal growth factor receptor (EGFR) pathway synergistically induces oncogenic transformation, which depends on EGFR-mediated activation of the RAS/RAF/MEK/ERK but not of the PI3K/AKT pathway. EGFR/MEK/ERK signaling induces JUN/activator protein 1 activation, which is essential for oncogenic transformation, in combination with the GLI activator forms GLI1 and GLI2. Furthermore, pharmacologic inhibition of EGFR and HH/GLI efficiently reduces growth of basal cell carcinoma (BCC) cell lines derived from mice with activated HH/GLI signaling. The results identify the synergistic integration of GLI activator function and EGFR signaling as a critical step in oncogenic transformation and provide a molecular basis for therapeutic opportunities relying on combined inhibition of the HH/GLI and EGFR/MEK/ERK/JUN pathway in BCC. [Cancer Res 2009;69(4):1284–92]
TMPRSS2-ERG Gene Fusion Is Not Associated with Outcome in Patients Treated by Prostatectomy
Authors: Gopalan Anuradha , Leversha Margaret A. , Satagopan Jaya M. , Zhou Qin , Al-Ahmadie Hikmat A. , Fine Samson W. , Eastham James A. , Scardino Peter T. , Scher Howard I. , Tickoo Satish K. , Reuter Victor E. , Gerald William L.
Published: February 2009

A significant number of prostate cancers have been shown to have recurrent chromosomal rearrangements resulting in the fusion of the androgen-regulated TMPRSS2 promoter to a member of the ETS transcription factor family, most commonly ERG. This results in ERG overexpression, which may have a direct causal role in prostate tumorigenesis or progression. However, the clinical significance of the rearrangement is unclear, and in particular, relationship to outcome has been inconsistent in recent reports. We analyzed TMPRSS2-ERG gene rearrangement status by fluorescence in situ hybridization in 521 cases of clinically localized surgically treated prostate cancer with 95 months of median follow-up and also in 40 unmatched metastases. Forty-two percent of primary tumors and 40% of metastases had rearrangements. Eleven percent had copy number increase (CNI) of the TMPRRS2-ERG region. Rearrangement alone was associated with lower grade, but not with stage, biochemical recurrence, metastases, or death. CNI with and without rearrangement was associated with high grade and advanced stage. Further, a subgroup of cancers with CNI and rearrangement by deletion, with two or more copies of the deleted locus, tended to be more clinically aggressive. DNA index assessment revealed that the majority of tumors with CNI of TMPRSS2-ERG had generalized aneuploidy/tetraploidy in contrast to tumors without TMPRSS2-ERG CNI, which were predominantly diploid. We therefore conclude that translocation of TMPRSS2-ERG is not associated with outcome, and the aggressive clinical features associated with CNI of chromosome 21 reflect generalized aneuploidy and are not due to CNI specifically of rearranged TMPRSS2-ERG. [Cancer Res 2009;69(4):1400–6]
Wilms' Tumor 1 Gene Expression in Hepatocellular Carcinoma Promotes Cell Dedifferentiation and Resistance to Chemotherapy
Authors: Perugorria Maria J. , Castillo Josefa , Latasa M. Ujue , Goñi Saioa , Segura Victor , Sangro Bruno , Prieto Jesús , Avila Matías A. , Berasain Carmen
Published: February 2009

The Wilms' tumor 1 gene (WT1) encodes a transcription factor involved in cell growth and development. As we previously reported, WT1 expression is hardly detectable in normal hepatic tissue but is induced in liver cirrhosis. Although WT1 has been found to be overexpressed in a number of malignancies, the role of WT1 in hepatocarcinogenesis has not been clarified. We found that WT1 is expressed in several human hepatocellular carcinoma (HCC) cell lines, including PLC/PRF/5 and HepG2, and in HCC tumor tissue in 42% of patients. WT1 small interfering RNAs did not affect proliferation rate of HCC cells but abrogated their resistance to anoikis. Transcriptome analysis of PLC/PRF/5 cells after WT1 knockdown showed up-regulation of 251 genes and down-regulation of 321. Ninety percent of the former corresponded to metabolic genes, mostly those characterizing the mature hepatocyte phenotype. On the contrary, genes that decreased upon WT1 inhibition were mainly related to defense against apoptosis, cell cycle, and tumor progression. In agreement with these findings, WT1 expression increased the resistance of liver tumor cells to doxorubicin, a compound used to treat HCC. Interestingly, doxorubicin strongly enhanced WT1 expression in both HCC cells and normal human hepatocytes. Among different chemotherapeutics, induction of WT1 transcription was restricted to topoisomerase 2 inhibitors. When WT1 expression was prohibited, doxorubicin caused a marked increase in caspase-3 activation. In conclusion, WT1 is expressed in a substantial proportion of HCC contributing to tumor progression and resistance to chemotherapy, suggesting that WT1 may be an important target for HCC treatment. [Cancer Res 2009;69(4):1358–67]
Altered Proliferation and Differentiation Properties of Primary Mammary Epithelial Cells from BRCA1 Mutation Carriers
Authors: Burga Laura N. , Tung Nadine M. , Troyan Susan L. , Bostina Mihnea , Konstantinopoulos Panagiotis A. , Fountzilas Helena , Spentzos Dimitrios , Miron Alexander , Yassin Yosuf A. , Lee Bernard T. , Wulf Gerburg M.
Published: February 2009

Female BRCA1 mutation carriers have a nearly 80% probability of developing breast cancer during their life-time. We hypothesized that the breast epithelium at risk in BRCA1 mutation carriers harbors mammary epithelial cells (MEC) with altered proliferation and differentiation properties. Using a three-dimensional culture technique to grow MECs ex vivo, we found that the ability to form colonies, an indication of clonality, was restricted to the aldehyde dehydrogenase 1–positive fraction in MECs but not in HCC1937 BRCA1-mutant cancer cells. Primary MECs from BRCA1 mutation carriers (n = 9) had a 28% greater ability for clonal growth compared with normal controls (n = 6; P = 0.006), and their colonies were significantly larger. Colonies in controls and BRCA1 mutation carriers stained positive for BRCA1 by immunohistochemistry, and 79% of the examined single colonies from BRCA1 carriers retained heterozygosity for BRCA1 (ROH). Colonies from BRCA1 mutation carriers frequently showed high epidermal growth factor receptor (EGFR) expression (71% EGFR positive versus 44% in controls) and were negative for estrogen receptor (ERα; 32% ER negative, 44% mixed, 24% ER positive versus 90% ER positive in controls). Expression of CK14 and p63 were not significantly different. Microarray studies revealed that colonies from BRCA1-mutant PMECs anticipate expression profiles found in BRCA1-related tumors, and that the EGFR pathway is up-regulated. We conclude that BRCA1 haploinsufficiency leads to an increased ability for clonal growth and proliferation in the PMECs of BRCA1 mutation carriers, possibly as a result of EGFR pathway activation. These altered growth and differentiation properties may render BRCA1-mutant PMECs vulnerable to transformation and predispose to the development of ER-negative, EGFR-positive breast cancers. [Cancer Res 2009;69(4):1273–8]
Telomere Attrition in Cancer Cells and Telomere Length in Tumor Stroma Cells Predict Chromosome Instability in Esophageal Squamous Cell Carcinoma: A Genome-Wide Analysis
Authors: Zheng Yun-Ling , Hu Nan , Sun Qing , Wang Chaoyu , Taylor Philip R.
Published: February 2009

Previous studies showed that chromosomal instability was common in esophageal squamous cell carcinoma (ESCC); however, the mechanisms underlying this instability are unknown. Individuals with deficiencies in telomere maintenance are susceptible to enhanced telomere loss during cell proliferation; such deficiencies could result in telomere dysfunction and genomic instability. We investigated the association between genome-wide chromosomal changes in cancer cells and telomere length/attrition in cancer/stroma cells in 47 ESCC patients. Genome-wide detection of loss of heterozygosity was performed using the Affymetrix GeneChip single nucleotide polymorphism arrays. Telomere length was assessed separately for cancer cells, carcinoma-associated fibroblasts (CAF), infiltrative lymphocytes, and adjacent normal epithelial cells by quantitative fluorescent in situ hybridization using paraffin-embedded sections. Telomere length differed significantly among cell types, such that length in infiltrative lymphocytes > CAFs > cancer cells. Shortened telomeres were observed in cancer cells in 44 of 47 (94%) of the tumors examined. Telomere length in CAFs was significantly associated with chromosomal instability on 4q and 13q and lymphocyte telomere length was significantly associated with instability on chromosomal arms 15q. Although telomere length in cancer cells was not associated with chromosome arm instability, telomere attrition in cancer cells, defined as the telomere length in CAFs minus the telomere length in cancer cells, was significantly associated with chromosomal instability on 13q and 15q. This study provides evidence that telomere shortening is a common genetic alteration in ESCC and that chromosome arm instability is related to both telomere attrition in cancer cells and telomere length in tumor stroma cells. [Cancer Res 2009;69(4):1604–14]
Marked Activity of Irinotecan and Rapamycin Combination toward Colon Cancer Cells In vivo and In vitro Is Mediated through Cooperative Modulation of the Mammalian Target of Rapamycin/Hypoxia-Inducible Factor-1α Axis
Authors: Pencreach Erwan , Guérin Eric , Nicolet Céline , Lelong-Rebel Isabelle , Voegeli Anne-Claire , Oudet Pierre , Larsen Annette K. , Gaub Marie-Pierre , Guenot Dominique
Published: February 2009

Purpose: Despite recent progress, colon cancer is often resistant to combination chemotherapy, highlighting the need for development of novel therapeutic approaches. An attractive target is hypoxia-inducible factor-1α (HIF-1α), a key transcription factor with a pivotal role in tumor cell metabolism. One potential class of therapeutic agents targeting HIF-1α are mammalian target of rapamycin inhibitors such as rapamycin. A second class are topoisomerase I inhibitors, such as irinotecan, which are able to inhibit the accumulation of HIF-1α. We here investigated whether combination of rapamycin and irinotecan was active in human colon cancer models.

Experimental Design: Human metastatic tumors were xenografted in nude mice and treated with low doses of irinotecan alone, rapamycin alone, or combination of both drugs. The cellular effects of irinotecan and rapamycin were further characterized for HT-29 and HCT-116 colon cancer cells in vitro.

Results: In contrast to single-agent therapy, xenografted tumors treated with combination of irinotecan and rapamycin showed potent inhibition of the mammalian target of rapamycin/HIF-1α axis, which was accompanied by a dramatic reduction in tumor volume. In vitro experiments showed that exposure to low concentrations of the two drugs resulted in massive HT-29 cell death under hypoxic, but not normoxic, conditions, in full agreement with a cytotoxic effect mediated through HIF-1α rather than through induction of genotoxic lesions. HCT-116 cells were less sensitive to the combined treatment due to constitutive activation of phosphatidylinositol 3-kinase/Akt and Ras/mitogen-activated protein kinase pathways.

Conclusion: These results identify HIF-1α as a promising target and provide a rationale for clinical trials of low-dose irinotecan and rapamycin combination toward metastatic colon cancer.
Longitudinal Analysis and Prognostic Effect of Cancer-Testis Antigen Expression in Multiple Myeloma
Authors: Atanackovic Djordje , Luetkens Tim , Hildebrandt York , Arfsten Julia , Bartels Katrin , Horn Christiane , Stahl Tanja , Cao Yanran , Zander Axel R. , Bokemeyer Carsten , Kröger Nicolaus
Published: February 2009

Purpose: Reliable data on the persistence of tumor expression of cancer-testis (CT) antigens over time and consequent analyses of the effect of CT antigen expression on the clinical course of malignancies are crucial for their evaluation as diagnostic markers and immunotherapeutic targets.

Experimental Design: Applying conventional reverse transcription-PCR, real-time PCR, and Western blot, we did the first longitudinal study of CT antigen expression in multiple myeloma analyzing 330 bone marrow samples from 129 patients for the expression of four CT antigens (MAGE-C1/CT7, MAGE-C2/CT10, MAGE-A3, and SSX-2).

Results: CT antigens were frequently and surprisingly persistently expressed, indicating that down-regulation of these immunogenic targets does not represent a common tumor escape mechanism in myeloma. We observed strong correlations of CT antigen expression levels with the clinical course of myeloma patients as indicated by the number of bone marrow–residing plasma cells and peripheral paraprotein levels, suggesting a role for CT antigens as independent tumor markers. Investigating the prognostic value of CT antigen expression in myeloma patients after allogeneic stem cell transplantation, we found that expression of genes, such as MAGE-C1, represents an important indicator of early relapse and dramatically reduced survival.

Conclusions: Our findings suggest that CT antigens might promote the progression of multiple myeloma and especially MAGE-C1/CT7, which seems to play the role of a “gatekeeper” gene for other CT antigens, might characterize a more malignant phenotype. Importantly, our study also strongly supports the usefulness of CT antigens as diagnostic and prognostic markers as well as therapeutic targets in myeloma.
Phase I and Pharmacokinetic Study of Pegylated Liposomal CKD-602 in Patients with Advanced Malignancies
Authors: Zamboni William C. , Ramalingam Suresh , Friedland David M. , Edwards Robert P. , Stoller Ronald G. , Strychor Sandra , Maruca Lauren , Zamboni Beth A. , Belani Chandra P. , Ramanathan Ramesh K.
Published: February 2009

Purpose: S-CKD602 is a pegylated liposomal formulation of CKD602, a semisynthetic camptothecin analogue. Pegylated (STEALTH) liposomes can achieve extended drug exposure in plasma and tumor. Based on promising preclinical data, the first phase I study of S-CKD602 was done in patients with refractory solid tumors.

Experimental Design: S-CKD602 was administered i.v. every 3 weeks. Modified Fibonacci escalation was used (three to six patients/cohort), and dose levels ranged from 0.1 to 2.5 mg/m2. Serial plasma samples were obtained over 2 weeks and total (lactone + hydroxyl acid) concentrations of encapsulated, released, and sum total (encapsulated + released) CKD602 measured by liquid chromatography-tandem mass spectrometry.

Results: Forty-five patients (21 males) were treated. Median age, 62 years (range, 33-79 years) and Eastern Cooperative Oncology Group status, 0 to 1 (43 patients) and 2 (2 patients). Dose-limiting toxicities of grade 3 mucositis occurred in one of six patients at 0.3 mg/m2, grade 3 and 4 bone marrow suppression in two of three patients at 2.5 mg/m2, and grade 3 febrile neutropenia and anemia in one of six patients at 2.1 mg/m2. The maximum tolerated dose was 2.1 mg/m2. Partial responses occurred in two patients with refractory ovarian cancer (1.7 and 2.1 mg/m2). High interpatient variability occurred in the pharmacokinetic disposition of encapsulated and released CKD602.

Conclusions: S-CKD602 represents a promising new liposomal camptothecin analogue with manageable toxicity and promising antitumor activity. Phase II studies of S-CKD602 at 2.1 mg/m2 i.v. once every 3 weeks are planned. Prolonged plasma exposure over 1 to 2 weeks is consistent with STEALTH liposomes and provides extended exposure compared with single doses of nonliposomal camptothecins.
Monoclonal antibody 16D10 to the COOH-terminal domain of the feto-acinar pancreatic protein targets pancreatic neoplastic tissues
Authors: Benkoël Liliane , Bernard Jean-Paul , Payan-Defais Marie-José , Crescence Lydie , Franceschi Cécile , Delmas Mireille , Ouaissi Mehdi , Sastre Bernard , Sahel José , Benoliel Anne-Marie , Bongrand Pierre , Silvy Françoise , Gauthier Laurent , Romagné François , Lombardo Dominique , Mas Eric
Published: February 2009

We have shown that the 16D10 antigen located on the mucin-like COOH-terminal domain of the feto-acinar pancreatic protein (FAPP) is expressed at the surface of human pancreatic tumor cell lines such as SOJ-6 cell line. Furthermore, an in vivo study indicates that targeting this cell-membrane glycopeptide by the use of the monoclonal antibody (mAb) 16D10 inhibits the growth of SOJ-6 xenografts in nude mice. To validate the potential use of the mAb16D10 in immune therapy, this study examined the expression of 16D10 antigens at the surface of human pancreatic adenocarcinomas versus control tissues. We examined the reactivity of mAb16D10 and mAb8H8 with pancreatic ductal adenocarcinomas (PDAC) compared with controls by using immunohistochemistry and confocal laser scanning microscopy. mAb8H8 does react with control or nontumoral human pancreatic tissues. mAb16D10 has a strong and specific reactivity with PDAC and does not react with other cancers of epithelia or normal tissues tested. Notable, mAb16D10 mostly recognizes membrane of tumoral cells. Furthermore, mAb8H8 and mAb16D10 recognized a protein of 110 to 120 kDa in homogenates of nontumoral and tumoral human pancreatic tissues, respectively. This size correlates with that of FAPP or with that of the normal counterpart of FAPP, the so-called bile salt-dependent lipase. The results suggest that mAb16D10 presents a unique specificity against PDAC; consequently, it could be effective in immune therapy of this cancer. Furthermore, mAb16D10 and mAb8H8 pair might be useful for diagnosis purpose in discriminating tumoral from nontumoral human pancreatic tissues. [Mol Cancer Ther 2009;8(2):282–91]
Interactions between PTEN and the c-Met pathway in glioblastoma and implications for therapy
Authors: Li Yunqing , Guessous Fadila , DiPierro Charles , Zhang Ying , Mudrick Tucker , Fuller Lauren , Johnson Elizabeth , Marcinkiewicz Lukasz , Engelhardt Matthew , Kefas Benjamin , Schiff David , Kim Jin , Abounader Roger
Published: February 2009

The tyrosine kinase receptor c-Met and its ligand hepatocyte growth factor (HGF) are frequently overexpressed and the tumor suppressor PTEN is often mutated in glioblastoma. Because PTEN can interact with c-Met-dependent signaling, we studied the effects of PTEN on c-Met-induced malignancy and associated molecular events and assessed the potential therapeutic value of combining PTEN restoration approaches with HGF/c-Met inhibition. We studied the effects of c-Met activation on cell proliferation, cell cycle progression, cell migration, cell invasion, and associated molecular events in the settings of restored or inhibited PTEN expression in glioblastoma cells. We also assessed the experimental therapeutic effects of combining anti-HGF/c-Met approaches with PTEN restoration or mTOR inhibition. PTEN significantly inhibited HGF-induced proliferation, cell cycle progression, migration, and invasion of glioblastoma cells. PTEN attenuated HGF-induced changes of signal transduction proteins Akt, GSK-3, JNK, and mTOR as well as cell cycle regulatory proteins p27, cyclin E, and E2F-1. Combining PTEN restoration to PTEN-null glioblastoma cells with c-Met and HGF inhibition additively inhibited tumor cell proliferation and cell cycle progression. Similarly, combining a monoclonal anti-HGF antibody (L2G7) with the mTOR inhibitor rapamycin had additive inhibitory effects on glioblastoma cell proliferation. Systemic in vivo delivery of L2G7 and PTEN restoration as well as systemic in vivo deliveries of L2G7 and rapamycin additively inhibited intracranial glioma xenograft growth. These preclinical studies show for the first time that PTEN loss amplifies c-Met-induced glioblastoma malignancy and suggest that combining anti-HGF/c-Met approaches with PTEN restoration or mTOR inhibition is worth testing in a clinical setting. [Mol Cancer Ther 2009;8(2):376–85]
CNOB/ChrR6, a new prodrug enzyme cancer chemotherapy
Authors: Thorne Steve H. , Barak Yoram , Liang Wenchuan , Bachmann Michael H. , Rao Jianghong , Contag Christopher H. , Matin A.
Published: February 2009

We report the discovery of a new prodrug, 6-chloro-9-nitro-5-oxo-5H-benzo(a)phenoxazine (CNOB). This prodrug is efficiently activated by ChrR6, the highly active prodrug activating bacterial enzyme we have previously developed. The CNOB/ChrR6 therapy was effective in killing several cancer cell lines in vitro. It also efficiently treated tumors in mice with up to 40% complete remission. 9-Amino-6-chloro-5H-benzo(a)phenoxazine-5-one (MCHB) was the only product of CNOB reduction by ChrR6. MCHB binds DNA; at nonlethal concentration, it causes cell accumulation in the S phase, and at lethal dose, it induces cell surface Annexin V and caspase-3 and caspase-9 activities. Further, MCHB colocalizes with mitochondria and disrupts their electrochemical potential. Thus, killing by CNOB involves MCHB, which likely induces apoptosis through the mitochondrial pathway. An attractive feature of the CNOB/ChrR6 regimen is that its toxic product, MCHB, is fluorescent. This feature proved helpful in in vitro studies because simple fluorescence measurements provided information on the kinetics of CNOB activation within the cells, MCHB killing mechanism, its generally efficient bystander effect in cells and cell spheroids, and its biodistribution. The emission wavelength of MCHB also permitted its visualization in live animals, allowing noninvasive qualitative imaging of MCHB in mice and the tumor microenvironment. This feature may simplify exploration of barriers to the penetration of MCHB in tumors and their amelioration. [Mol Cancer Ther 2009;8(2):333–41]
Dihydrofolate reductase amplification and sensitization to methotrexate of methotrexate-resistant colon cancer cells
Authors: Morales Cristina , García Maria J. , Ribas Maria , Miró Rosa , Muñoz Mar , Caldas Carlos , Peinado Miguel A.
Published: February 2009

Gene amplification is one of the most frequent manifestations of genomic instability in human tumors and plays an important role in tumor progression and acquisition of drug resistance. To better understand the factors involved in acquired resistance to cytotoxic drugs via gene amplification, we have analyzed the structure and dynamics of dihydrofolate reductase (DHFR) gene amplification in HT29 cells treated with methotrexate (MTX). Analysis of the DHFR gene amplification process shows that the amplicon exhibits a complex structure that is consistently reproduced in independent treatments. The cytogenetic manifestation of the amplification in advanced stages of the treatment may be in the form of double minutes or as a homogeneously stained region. To get insights into the mechanisms of resistance, we have also investigated the sensitization to MTX of MTX-resistant cells after drug withdrawal and reexposure to MTX. Passive loss of the DHFR amplicon by withdrawal of the drug results in MTX-sensitive cells exhibiting a substantial reduction of their capacity or even an incapacity to generate resistance when submitted to a second cycle of MTX treatment. On a second round of drug administration, the resistant cells generate a different amplicon structure, suggesting that the formation of the amplicon as in the first cycle of treatment is not feasible. These results indicate that DHFR gene amplification is a “wear and tear” process in HT29 cells and that MTX-resistant cells may become responsive to a second round of treatment if left untreated during a sufficient period of time. [Mol Cancer Ther 2009;8(2):424–32]
Mechanisms involved in synergistic anticancer effects of anti-4-1BB and cyclophosphamide therapy
Authors: Kim Young H. , Choi Beom K. , Oh Ho S. , Kang Woo J. , Mittler Robert S. , Kwon Byoung S.
Published: February 2009

Chemotherapy can precondition for immunotherapy by creating an environment for homeostatic lymphoproliferation and eliminating some of the suppressive immune networks. We found that combination therapy with anti-4-1BB and cyclophosphamide (CTX) produced synergistic anticancer effects in the poorly immunogenic B16 melanoma model in mice. The antitumor effect of the combination therapy depended mainly on CD8+ T cells, the 4-1BB–dependent expansion and differentiation of which into IFN-γ–producing CD11c+CD8+ T cells was enhanced by CTX. Anti-4-1BB induced a rapid repopulation of T and B cells from CTX-mediated lymphopenia. Anti-4-1BB protected naïve T cells from CTX and promoted proliferation of memory/effector and memory T cells. The combination treatment produced ∼60- and 2.2-fold more CTLs per tumor-associated antigen compared with CTX or anti-4-1BB alone, respectively. This indicates that anti-4-1BB promoted a preferential expansion of tumor-specific CD8+ T cells among the repopulated lymphocytes following CTX-mediated lymphopenia. CTX treatment enhanced 4-1BB expression on CD4 and CD8 T cells, and CTX alone or in combination with anti-4-1BB effectively suppressed peripheral regulatory T cells. Our results indicate that anti-4-1BB and CTX can be practical partners in cancer therapy because CTX creates an environment in which anti-4-1BB actively promotes the differentiation and expansion of tumor-specific CTLs. [Mol Cancer Ther 2009;8(2):469–78
Whole-Cell Bioprocessing of Human Fetal Cells for Tissue Engineering of Skin
Authors: Applegate L.A. , Scaletta C. , Hirt-Burri N. , Raffoul W. , Pioletti D.
Published: February 2009

Current restrictions for human cell-based therapies have been related to technological limitations with regards to cellular proliferation capacity (simple culture conditions), maintenance of differentiated phenotype for primary human cell culture and transmission of communicable diseases. Cultured primary fetal cells from one organ donation could possibly meet the exigent and stringent technical aspects for development of therapeutic products. Master and working cell banks from one fetal organ donation (skin) can be developed in short periods of time and safety tests can be performed at all stages of cell banking. For therapeutic use, fetal cells can be used up to two thirds of their life-span in an out-scaling process and consistency for several biological properties includes protein concentration, gene expression and biological activity. As it is the intention that banked primary fetal cells can profit from the prospected treatment of hundreds of thousands of patients with only one organ donation, it is imperative to show consistency, tracability and safety of the process including donor tissue selection, cell banking, cell testing and growth of cells in out-scaling for the preparation of whole-cell tissue-engineering products.
In vitro Irritation Models and Immune Reactions
Authors: Gibbs S.
Published: February 2009

Irritant contact dermatitis is the result of an innate inflammatory response of the skin to direct injury. It is caused by a single, repeated or continued application of an irritant, with the source most often being a chemical. Therefore, European regulations require strict screening of all ingredients in consumer products. Until recently, identifying a potential irritant has completely relied on animal testing (for example, Draize test). Besides the ethical problems, both the 7th Amendment to the Cosmetics Directive and Registration, Evaluation and Authorization of Chemicals legislation have stimulated the development of alternative tests for the assessment of potential toxicological effects of substances. This review is aimed at describing current in vitro skin irritation models and the biomarkers used to assess the degree of irritancy of a potential irritant. Four models are described: keratinocyte and fibroblast cultures grown under submerged culture conditions, epidermal equivalents, skin equivalents and freshly isolated skin. Biomarkers such as IL-1α, IL-6, IL-8, PGE2, SKALP, HSP70 and kinases are described along with changes in metabolic activity (MTT assay) and cytosolic leakage (lactate dehydrogenase assay). Noticeable is the limited number of genomic and proteomic studies. Such studies have the potential to identify novel biomarkers and to elucidate the mechanism of irritant contact dermatitis.
Melanocytes: From Morphology to Application
Authors: Santiago-Walker A. , Li L. , Haass N.K. , Herlyn M.
Published: February 2009

Melanocytes in human skin are intricately regulated by keratinocytes and the surrounding stroma. The development of melanoma is thought to arise from disrupted melanocyte homeostasis. It is now known that microenvironment plays a major role in maintenance of cellular homeostasis and can contribute to tumor initiation and tumor progression. Historically, melanocyte studies have been performed in two-dimensional culture systems, and often with melanocytes cultured in the absence of keratinocytes. Here we present the biological basis for the use of organotypic, three-dimensional model systems in the study of melanoma, and highlight the features of the most utilized organotypic model sytems.
Die äussere Wendung bei Beckenendlage: Renaissance eines altbekannten Verfahrens?
Authors: Schmidt M. , Callies R. , Kuhn U. , Willruth A. , Kimmig R.
Published: February 2009

Fragestellung: Eine Beckenendlage liegt bei etwa 3–4% aller Schwangerschaften am Termin vor. Eine äussere Wendung bietet eine Möglichkeit, hohe Sectioraten wegen Beckenendlage zu reduzieren. Diese Untersuchung beleuchtet retrospektiv den Ausgang von 51 Versuchen einer äusseren Wendung an unserer Klinik. Methoden:Es wurden insgesamt 51 Versuche einer äusseren Wendung an der Universitätsfrauenklinik zwischen der 37. und 41. Schwangerschaftswoche (SSW) durchgeführt. Ergebnisse: In 32 von 51 Fällen (62,7%) gelang die äussere Wendung mit einer Rate an darauf folgenden vaginalen Geburten von 71,9%. In der 37. SSW ergibt sich die höchste Rate an erfolgreichen Wendungen (81,25%), von denen 76,9% auf vaginalem Wege entbunden werden konnten. Komplikationen waren selten, lediglich in 1 Fall musste eine Notsectio bei persistierender fetaler Bradykardie durchgeführt werden. Schlussfolgerung:Der Versuch der äusseren Wendung ist ein effektives und risikoarmes Verfahren, um eine risikoärmere vaginale Geburt aus Schädellage zu ermöglichen. Der günstigste Zeitpunkt hierfür ist die 37. SSW.
Encoding Emotions in Speech with the Size Code
Authors: Chuenwattanapranithi Suthathip , Xu Yi , Thipakorn Bundit , Maneewongvatana Songrit
Published: February 2009

Our current understanding of how emotions are expressed in speech is still very limited. Part of the difficulty has been the lack of understanding of the underlying mechanisms. Here we report the findings of a somewhat unconventional investigation of emotional speech. Instead of looking for direct acoustic correlates of multiple emotions, we tested a specific theory, the size code hypothesis of emotional speech, about two emotions – anger and happiness. According to the hypothesis, anger and happiness are conveyed in speech by exaggerating or understating the body size of the speaker. In two studies consisting of six experiments, we synthesized vowels with a three-dimensional articulatory synthesizer with parameter manipulations derived from the size code hypothesis, and asked Thai listeners to judge the body size and emotion of the speaker. Vowels synthesized with a longer vocal tract and lower F0 were mostly heard as from a larger person if the length and F0 differences were stationary, but from an angry person if the vocal tract was dynamically lengthened and F0 was dynamically lowered. The opposite was true for the perception of small body size and happiness. These results provide preliminary support for the size code hypothesis. They also point to potential benefits of theory-driven investigations in emotion research.
Effective Determination of Dry Weight by Intradialytic Bioimpedance Analysis in Hemodialysis
Authors: Chongthanakorn Kamonrat , Tiranathanagul Khajohn , Susantitaphong Paweena , Praditpornsilpa Kearkiat , Eiam-Ong Somchai
Published: February 2009

Background: The new dry weight (DW) assessment technique by intradialytic sequential bioimpedance analysis (BIA) was evaluated in this study. Methods: Intradialytic changes in the ratio of resistance at baseline per each time point (R₀/Rt) determined by a total body single-frequency BIA were recorded in 19 hemodialysis patients. The bioimpedance DW (BIADW) could be drawn from a time point at which R₀/Rt was constant. Results: After the first session where the previous DW was prescribed, the participants could be divided into 2 groups: the under BIADW and over BIADW groups. In the under BIADW group, the BIADW was achieved earlier than the previous DW. The intradialytic symptoms disappeared without changes in the home-monitored mean blood pressure and antihypertensive agents at 1-month follow-up. In the over BIADW group, the BIADW could be obtained in the following sessions and the prescribed DW could be gradually reduced. The home-monitored mean blood pressure was decreased and the numbers of antihypertensive drugs were reduced. Conclusion: Intradialytic single-frequency BIA assessment can be used as a tool to accurately determine the DW.
Correlation between Pulse Wave Velocity and Fluid Distribution in Hemodialysis Patients
Authors: Zheng Danxia , Cheng Li-Tao , Zhuang Zhen , Gu Yue , Tang Li-Jun , Wang Tao
Published: February 2009

Background: In this study, we focused on whether volume overload plays a role in the development of arterial stiffness. Methods: Seventy-three prevalent hemodialysis patients were enrolled in a cross-sectional study. Arterial stiffness was assessed by carotid-femoral pulse wave velocity (PWV), and volume overload was assessed by bioimpedance analysis. Results: Patients were divided into a high PWV group and a low PWV group based on the median of PWV. Age, systolic blood pressure, pulse pressure (PP), extracellular water/total body water ratio (ECW/TBW), diabetic status (all p < 0.01), and history of cardiac events (p < 0.05) were significantly higher in the high PWV group (n = 37) than in the low PWV group. In the correlation analysis, PWV was positively associated with PP, systolic blood pressure, ECW/TBW, age, history of cardiac events, and diabetes (all p < 0.01). Multiple regression analysis showed that PWV was independently related to PP and ECW/TBW (p < 0.01). Conclusion: Volume overload plays an important role in the development of arterial stiffness in hemodialysis patients.
Mycophenolate Mofetil in High-Risk Patients with Primary Glomerulonephritis: Results of a 1-Year Prospective Study
Authors: Dimkovic Nada , Jovanovic Dragan , Kovacevic Zoran , Rabrenovic Violeta , Nesic Vidosava , Savin Marina , Mitic Branka , Ratkovic Marina , Curic Slobodan , Mitic Igor , Pljesa Steva , Perunicic-Pekovic Gordana , Marinkovic Jelena , Popovic Jovan , Vujic Danica
Published: February 2009

Background/Aims: Glucocorticoids and classic immunosuppressive drugs can improve disease activity in primary glomerulonephritis (GN). However, these drugs have serious toxicity and patients frequently experience inadequate response or relapse, so there is a need for alternative agents. This multicenter uncontrolled study analyzed the efficacy and safety of mycophenolate mofetil (MMF) in high-risk patients with primary GN. Methods: A total of 51 patients with biopsy-proven membranous (n = 12), membranoproliferative (n = 15), mesangioproliferative (n = 10), focal segmental glomerulosclerosis (n = 13) and minimal change disease (n = 1) received MMF with low-dose corticosteroids for 1 year. The primary outcome included the number of patients with complete/partial remission. Results: Proteinuria significantly decreased, from its median value of 4.9 g/day (IQR 2.9–8.4) to 1.28 g/day (IQR 0.5–2.9), p < 0.001. The urine protein/creatinine ratio significantly improved, from a median of 3.72 (IQR 2.13–6.48) to 0.84 (IQR 0.42–2.01), p < 0.001. The mean area under the curve for proteinuria significantly decreased, from 4.99 ± 3.46 to 2.16 ± 2.46, between the first (visits 1–2) and last (vists 4–5) treatment periods (p < 0.001). The change was similar for every type of GN, without difference between groups. eGFR slightly increased (62.1 ± 31.8 to 65.3 ± 31.8 ml/min, p = n.s.) and ESR, total proteins, albumins, total- and HDL-cholesterol parameters improved significantly. Systolic, diastolic and mean blood pressure decreased (p < 0.02 for systolic blood pressure). The age of patients was the only independent predictor of complete or partial remission. Conclusion: MMF proved to be efficient in 70% of high-risk patients with primary GN, who reached either complete or partial remission without safety concern after 12 months of treatment. Favorable effects of MMF therapy have to be confirmed in the long term and particularly after discontinuation of the drug.
Chronic Kidney Disease in India: Challenges and Solutions
Authors: Agarwal S.K. , Srivastava R.K.
Published: February 2009

Chronic diseases have become a major cause of global morbidity and mortality even in developing countries. The burden of chronic kidney disease (CKD) in India cannot be assessed accurately. The approximate prevalence of CKD is 800 per million population (pmp), and the incidence of end-stage renal disease (ESRD) is 150–200 pmp. The most common cause of CKD in population-based studies is diabetic nephropathy. India currently has 820+ nephrologists, 710+ hemodialysis units with 2,500+ dialysis stations and 4,800+ patients on CAPD. There are 172+ transplant centers, two-thirds of which are in South India and mostly privately run. Nearly 3,500 transplants are done annually, the total number of cadaver donors being approximately 700 till now. Thus, taken together, nearly 18,000–20,000 patients (10% of new ESRD cases) in India get renal replacement therapy. The cost of single hemodialysis varies between USD 15 and 40 with an additional cost of erythropoietin being USD 150–200/month. The cost of CAPD using a ‘Y’ set with 3 exchanges/week is USD 400/month. The cost of the transplant procedure in a state-run hospital is USD 800–1,000, and the cost of immunosuppression using tacrolimus, steroid and mycophenolate is USD 350–400/month. Until recently, the government did not recognize CKD/ESRD as a significant problem in India. However, some illustrious activities in relation to CKD brought attention of the media and policymakers to this very common but till now deprived group of diseases. On the one side the government has initiated a process by which it is planning to establish stand-alone hemodialysis units in the country to increase the facilities at an affordable cost, and on the transplant side it had launched a National Organ Transplant Program to facilitate transplantation on a national scale. Hemodialysis program is halfway to being implemented. Thus, in India there is still a long way to go with respect to CKD. Until then, in a country like India, screening of high-risk individuals for CKD and the risk factors is the best bet.
Memantine Therapy of Behavioral Symptoms in Community-Dwelling Patients with Moderate to Severe Alzheimer’s Disease
Authors: Grossberg George T. , Pejović Vojislav , Miller Michael L. , Graham Stephen M.
Published: February 2009

Memantine is a moderate-affinity, uncompetitive antagonist of N-methyl-D-aspartate receptors, approved for the treatment of moderate to severe Alzheimer’s disease (AD). Available data suggest that, in addition to its benefits on cognition, function, and global status, memantine treatment may also help alleviate behavioral symptoms. This article provides an overview of the prevalence, assessment, and treatment of behavioral disturbances in AD, and summarizes current knowledge regarding the effects of memantine on the behavior of community-dwelling patients. We searched EMBASE and PubMed (January 1992 to October 2008) for reports on memantine trials that involved outpatients with moderate to severe AD. All previously unpublished data were obtained from Forest Laboratories, Inc. Behavioral outcomes were assessed in three completed, double-blind, placebo-controlled trials.Overall, patients who received memantine performed better on behavioral measures than those treated with placebo. Post-hoc analyses suggest that memantine treatment was associated with a reduced severity or emergence of specific symptoms, particularly agitation and aggression. Prospective, well-designed trials are warranted to evaluate the efficacy of memantine in patients with significant behavioral symptoms.
Percutaneous Fetoscopic Laser Decompression of Congenital High Airway Obstruction Syndrome (CHAOS) from Laryngeal Atresia via a Single Trocar – Current Technical Constraints and Potential Solutions for Future Interventions
Authors: Kohl Thomas , Van de Vondel Patricia , Stressig Rüdiger , Wartenberg Hans C. , Heep Axel , Keiner Sabine , Müller Andreas , Franz Axel , Fröhlich Susanne , Willinek Winfried , Gembruch Ulrich
Published: February 2009

Objective: To alleviate congenital high airway obstruction syndrome (CHAOS) from laryngeal atresia by percutaneous minimally-invasive fetoscopic tracheal decompression using laser. Methods: The procedure was performed via one trocar under general maternofetal anesthesia in a human fetus with CHAOS from laryngeal atresia at 21+6 weeks of gestation. Results: Normalization of the lung-heart size relationship was observed within days after the procedure. The fetus was delivered by ex utero intrapartum treatment (EXIT) in order to perform a tracheotomy at 31+1 weeks of gestation and survived hospital treatment to discharge. Conclusions: Percutaneous minimally-invasive fetoscopic decompression of the fetal trachea via a single trocar is feasible in human fetuses with CHAOS from laryngeal atresia.
A Lagged Warm Event–Like Response to Peaks in Solar Forcing in the Pacific Region
Authors: Meehl Gerald A. , Arblaster Julie M.
Published: February 2009

The forced response coincident with peaks in the 11-yr decadal solar oscillation (DSO) has been shown to resemble a cold event or La Niña–like pattern during December–February (DJF) in the Pacific region in observations and two global coupled climate models. Previous studies with filtered observational and model data have indicated that there could be a lagged warm event or El Niño–like response following the peaks in the DSO forcing by a few years. Here, observations and two climate model simulations are examined, and it is shown that dynamical coupled processes initiated by the response in the tropical Pacific to peaks in solar forcing produce wind-forced ocean Rossby waves near 5°N and 5°S. These reflect off the western boundary, producing downwelling equatorial Kelvin waves that contribute to transitioning the tropical Pacific to a warm event or El Niño–like pattern that lags the peaks in solar forcing by a few years.
New Altimetric Estimates of Mode-1 M2 Internal Tides in the Central North Pacific Ocean
Authors: Zhao Zhongxiang , Alford Matthew H.
Published: February 2009

New estimates of mode-1 M2 internal tide energy flux are computed from an extended Ocean Topography Experiment (TOPEX)/Poseidon (T/P) altimeter dataset that includes both the original and tandem tracks, improving spatial resolution over previous estimates from O(500 km) to O(250 km). Additionally, a new technique is developed that allows separate resolution of northward and southward components. Half-wavelength features previously seen in unseparated estimates are shown to be due to the superposition of northward and southward wave trains. The new technique and higher spatial resolution afford a new view of mode-1 M2 internal tides in the central North Pacific Ocean. As with all altimetric estimates, only the coherent or phase-locked signals are detectable owing to the long repeat period of the tracks. Emanating from specific generation sites consistent with predictions from numerical models, internal tidal beams 1) are as narrow as 200 km and 2) propagate a longer distance than previously observed. Two northward internal tidal beams radiating from the Hawaiian Ridge, previously obscured by coarse resolution and the southward Aleutian beam, are now seen to propagate more than 3500 km across the North Pacific Ocean to reach the Alaskan shelf. The internal tidal beams are much better resolved than in previous studies, resulting in better agreement with moored flux estimates.