bluuebunny/crossref_metadata_2025 huggingface dataset:
Impaired Skin and Mammary Gland Development and Increased γ-Irradiation–Induced Tumorigenesis in Mice Carrying a Mutation of S1152-ATM Phosphorylation Site in Brca1
Authors: Kim Sang Soo , Cao Liu , Baek Hye Jung , Lim Sung-Chul , Li Cuiling , Wang Rui-Hong , Xu Xiaoling , Cho Kwan Ho , Deng Chu-Xia
Published: December 2009

The tumor suppressor BRCA1 interacts with many proteins and undergoes multiple modifications on DNA damage. ATM, a key molecule of the DNA damage response, phosphorylates S1189 of BRCA1 after γ-irradiation. S1189 of BRCA1 is known as a unique ATM phosphorylation site in BRCA1 exon 11. To study the functions of ATM-dependent phosphorylation of BRCA1-S1189, we generated a mouse model carrying a mutation of S1152A (S1152 in mouse Brca1 corresponds to S1189 in human BRCA1) by gene targeting. Brca1S1152A/S1152A mice were born at the expected ratio, unlike that seen in previous studies of Brca1-null mice. However, 36% of Brca1S1152A/S1152A mice exhibited aging-like phenotypes including growth retardation, skin abnormalities, and delay of the mammary gland morphogenesis, with an increase in apoptosis. Mutant mice were hypersensitive to high doses of γ-irradiation, displaying shortened life span and reduction in intestinal villus size, associated with increased apoptosis. Aging-unaffected 18-month-old Brca1S1152A/S1152A female mice also showed mammary gland abnormalities with increased levels of cyclin D1 and phospho-ER-α, such as Brca1-Δ11 mutation. On low-dose γ-irradiation, they suffered a marked increase in tumor formation with an abnormal coat pattern. Furthermore, Brca1S1152A/S1152A embryonic fibroblasts failed to accumulate p53 on γ-irradiation with delayed phosphorylation of p53-S23. These observations indicate that ATM-mediated phosphorylation of S1189 is required for BRCA1 functions in the modulation of DNA damage response and in the suppression of tumor formation by regulating p53 and apoptosis. [Cancer Res 2009;69(24):9291–300]
ZBRK1 Acts as a Metastatic Suppressor by Directly Regulating MMP9 in Cervical Cancer
Authors: Lin Li-Fang , Chuang Chih-Hung , Li Chien-Feng , Liao Ching-Chun , Cheng Chun-Pei , Cheng Tian-Lu , Shen Meng-Ru , Tseng Joseph T. , Chang Wen-Chang , Lee Wen-Hwa , Wang Ju-Ming
Published: December 2009

The BRCA1-interacted transcriptional repressor ZBRK1 has been associated with antiangiogenesis, but direct evidence of a tumor suppressor role has been lacking. In this study, we provide evidence of such a role in cervical carcinoma. ZBRK1 levels in cervical tumor cells were significantly lower than in normal cervical epithelial cells. In HeLa cervical cancer cells, enforced expression inhibited malignant growth, invasion, and metastasis in a variety of in vitro and in vivo assays. Expression of the metalloproteinase MMP9, which is known to be an important driver of invasion and metastasis, was found to be inversely correlated with ZBRK1 in tumor tissues and a target for repression in tumor cells. Our findings suggest that ZBRK1 acts to inhibit metastasis of cervical carcinoma, perhaps by modulating MMP9 expression. Cancer Res; 70(1); 192–201
Mutant Metabolic Enzymes Are at the Origin of Gliomas
Authors: Yan Hai , Bigner Darell D. , Velculescu Victor , Parsons D. Williams
Published: December 2009

Mutations of the isocitrate dehydrogenase (IDH) metabolic enzymes IDH1 and IDH2 have been found to be frequent and early genetic alterations in astrocytomas and oligodendrogliomas. All mutations identified to date affect a single amino acid located within the isocitrate binding site (R132 of IDH1 and the analogous R172 residue of IDH2). IDH1 and IDH2 mutations define a specific subtype of gliomas and may have significant utility for the diagnosis, prognosis, and treatment of patients with these tumors. [Cancer Res 2009;69(24):9157–9]
Antigen Presentation by Dendritic Cells in Tumors Is Disrupted by Altered Metabolism that Involves Pyruvate Kinase M2 and Its Interaction with SOCS3
Authors: Zhang Zhuohan , Liu Qiaofei , Che Yongzhe , Yuan Xin , Dai Lingyun , Zeng Bin , Jiao Guohui , Zhang Yin , Wu Xue , Yu Yinyan , Zhang Yuan , Yang Rongcun
Published: December 2009

Dendritic cell (DC) function is negatively affected by tumors and tumor-derived factors, but little is known about the underlying mechanisms. Here, we show that intracellular SOCS3 in DCs binds to pyruvate kinase type M2 (M2-PK), which plays a critical role in ATP production through glycolysis. The interaction of SOCS3 with M2-PK reduced ATP production and impaired DC-based immunotherapy against tumors. Thus, SOCS3, which has been shown to be upregulated by tumor-derived factors, interacts with M2-PK to decrease ATP production, causing DC dysfunction. These dysfunctional DCs have a reduced ability to present antigens. Alteration of DC metabolism mediated by SOCS3 represents a novel mechanism for DC dysfunction in the tumor microenvironment. Cancer Res; 70(1); 89–98
The Aryl Hydrocarbon Receptor Functions as a Tumor Suppressor of Liver Carcinogenesis
Authors: Fan Yunxia , Boivin Gregory P. , Knudsen Erik S. , Nebert Daniel W. , Xia Ying , Puga Alvaro
Published: December 2009

The aryl hydrocarbon receptor (AHR) is a ligand-activated transcription factor that mediates the biological and toxic effects of its xenobiotic ligands. Previous cell culture studies have shown that, in addition to controlling the xenobiotic detoxification response, AHR activation leads to G0-G1 arrest, diminished capacity for DNA replication, and inhibition of cell proliferation. In fact, recent work from our own and from other laboratories suggests that AHR may function as a tumor suppressor gene that becomes silenced during the process of tumor formation. To test this hypothesis and determine whether the mouse Ahr gene acts as a tumor suppressor gene in vivo, we have examined the role of Ahr ablation in liver tumorigenesis induced by the genotoxic chemical diethylnitrosamine (DEN), a hepatic carcinogen that is not an AHR ligand. In mice given a single i.p. injection of DEN, AHR antagonized liver tumor formation and growth by regulating cell proliferation, inflammatory cytokine expression, and DNA damage, parameters which were significantly elevated in the livers of control and, more so, of DEN-exposed Ahr−/− mice. Ahr−/− hepatocytes also showed significantly higher numbers of 4N cells, increased expression of proliferative markers, and repression of tumor suppressor genes. These data support the concept that in its basal state in the absence of a xenobiotic ligand, the Ahr gene functions as a tumor suppressor gene, and that its silencing may be associated with cancer progression. Cancer Res; 70(1); 212–220
A Gold(III) Porphyrin Complex with Antitumor Properties Targets the Wnt/β-catenin Pathway
Authors: Chow Kim Hei-Man , Sun Raymond Wai-Yin , Lam Janice B.B. , Li Carrie Ka-Lei , Xu Aimin , Ma Dik-Lung , Abagyan Ruben , Wang Yu , Che Chi-Ming
Published: December 2009

Gold(III) complexes have shown promise as antitumor agents, but their clinical usefulness has been limited by their poor stability under physiological conditions. A novel gold(III) porphyrin complex [5-hydroxyphenyl-10,15,20-triphenylporphyrinato gold(III) chloride (gold-2a)] with improved aqueous stability showed 100-fold to 3,000-fold higher cytotoxicity than platinum-based cisplatin and IC50 values in the nanomolar range in a panel of human breast cancer cell lines. Intraductal injections of gold-2a significantly suppressed mammary tumor growth in nude mice. These effects are attributed, in part, to attenuation of Wnt/β-catenin signaling through inhibition of class I histone deacetylase (HDAC) activity. These data, in combination with computer modeling, suggest that gold-2a may represent a promising class of anticancer HDAC inhibitor preferentially targeting tumor cells with aberrant Wnt/β-catenin signaling. Cancer Res; 70(1); 329–37
14-3-3η Amplifies Androgen Receptor Actions in Prostate Cancer
Authors: Titus Mark A. , Tan Jiann-an , Gregory Christopher W. , Ford O. Harris , Subramanian Romesh R. , Fu Haian , Wilson Elizabeth M. , Mohler James L. , French Frank S.
Published: December 2009

Purpose: Androgen receptor abundance and androgen receptor–regulated gene expression in castration-recurrent prostate cancer are indicative of androgen receptor activation in the absence of testicular androgen. Androgen receptor transactivation of target genes in castration-recurrent prostate cancer occurs in part through mitogen signaling that amplifies the actions of androgen receptor and its coregulators. Herein we report on the role of 14-3-3η in androgen receptor action.

Experimental Design and Results: Androgen receptor and 14-3-3η colocalized in COS cell nuclei with and without androgen, and 14-3-3η promoted androgen receptor nuclear localization in the absence of androgen. 14-3-3η interacted with androgen receptor in cell-free binding and coimmunoprecipitation assays. In the recurrent human prostate cancer cell line, CWR-R1, native endogenous androgen receptor transcriptional activation was stimulated by 14-3-3η at low dihydrotestosterone concentrations and was increased by epidermal growth factor. Moreover, the dihydrotestosterone- and epidermal growth factor–dependent increase in androgen receptor transactivation was inhibited by a dominant negative 14-3-3η. In the CWR22 prostate cancer xenograft model, 14-3-3η expression was increased by androgen, suggesting a feed-forward mechanism that potentiates both 14-3-3η and androgen receptor actions. 14-3-3η mRNA and protein decreased following castration of tumor-bearing mice and increased in tumors of castrate mice after treatment with testosterone. CWR22 tumors that recurred 5 months after castration contained 14-3-3η levels similar to the androgen-stimulated tumors removed before castration. In a human prostate tissue microarray of clinical specimens, 14-3-3η localized with androgen receptor in nuclei, and the similar amounts expressed in castration-recurrent prostate cancer, androgen-stimulated prostate cancer, and benign prostatic hyperplasia were consistent with androgen receptor activation in recurrent prostate cancer.

Conclusion: 14-3-3η enhances androgen- and mitogen-induced androgen receptor transcriptional activity in castration-recurrent prostate cancer. (Clin Cancer Res 2009;15(24):7571–81)
Interactions between MDM2 and TP53 Genetic Alterations, and Their Impact on Response to MDM2 Inhibitors and Other Chemotherapeutic Drugs in Cancer Cells
Authors: Liu Wanqing , He Lijun , Ramírez Jacqueline , Ratain Mark J.
Published: December 2009

Purpose: MDM2 is a key negative regulator of the p53 signaling pathway. We aimed to evaluate the inter-relationships between MDM2 SNP309, mRNA expression, amplification, and TP53 mutations, as well as their correlations with responsiveness to MDM2 inhibitors and other commonly used cytotoxic drugs tested in the NCI-60 cancer cell panel.

Experimental Design: SNP309 was genotyped in the NCI-60 cancer cell lines. MDM2 mRNA levels and gene copy number were measured using real-time PCR. We assessed the inter-relationship between MDM2 genetic alterations, TP53 mutations, and the cytotoxicity of two MDM2 inhibitors (RITA and Nutlin-3) as well as 111 other drugs with known mechanisms of action.

Results: In the overall NCI-60 cell panel, MDM2 mRNA levels were not associated with SNP309 but with increased gene copy number. However, SNP309 strongly determined the MDM2 mRNA expression in cancer cells with wild-type TP53. Cancer cells with wild-type TP53 also had significantly higher MDM2 copies. In the overall panel, MDM2 copy number was independently correlated with increased sensitivity to commonly used alkylating agents and topoisomerase I and II inhibitors. SNP309 was significantly associated with increased sensitivity to alkylating agents and topoisomerase I inhibitors in the cells with wild-type TP53. In addition, TP53 mutations were the only factor significantly associated with cellular resistance to the MDM2 inhibitor RITA.

Conclusions: Our results suggest that MDM2 copy number and SNP309 may predict for response to alkylating agents and topoisomerase inhibitors. These markers should be tested further, particularly in combination with other putative predictive biomarkers. (Clin Cancer Res 2009;15(24):7602–7)
Predictive Potential of Angiogenic Growth Factors and Circulating Endothelial Cells in Breast Cancer Patients Receiving Metronomic Chemotherapy Plus Bevacizumab
Authors: Calleri Angelica , Bono Anna , Bagnardi Vincenzo , Quarna Jessica , Mancuso Patrizia , Rabascio Cristina , Dellapasqua Silvia , Campagnoli Elisabetta , Shaked Yuval , Goldhirsch Aron , Colleoni Marco , Bertolini Francesco
Published: December 2009

Purpose: The association of chemotherapy and antiangiogenic drugs has shown efficacy in clinical oncology. However, there is a need for biomarkers that allow selection of patients who are likely to benefit from such treatment and are useful for indicating best drug combination and schedule.

Experimental Design: We investigated the predictive potential of six angiogenic molecules/transcripts and nine subpopulations of circulating endothelial cells (CEC) and progenitors (CEP) in 46 patients with advanced breast cancer treated with metronomic cyclophosphamide and capecitabine plus bevacizumab.

Results: Median time to progression was 281 days. Baseline CECs higher than the first quartile were associated with an increased time to progression (P = 0.021). At progression, CECs were markedly reduced (P = 0.0002). In the cohort of 15 long-term responders, who progressed later than 1 year after beginning of therapy, circulating vascular endothelial growth factor (VEGF)-A levels measured after 2 months of therapy were significantly reduced, and there were significant trends toward lower levels of PDGF-BB, CEPs, and CECs. At the time of progression, angiogenic growth factors VEGF-A and basic fibroblast growth factor were significantly increased.

Conclusions: Baseline CECs (likely reflecting an active vascular turnover) predicted a prolonged clinical benefit. At the time of relapse, a pattern of decreased CECs and increased angiogenic growth factors suggested a switch toward a different type of cancer vascularization. VEGF-A and basic fibroblast growth factor levels after 2 months of therapy were also useful to identify patients whose disease was likely to progress. These biomarkers are likely to be useful for treatment selection and might be incorporated in design of future studies. (Clin Cancer Res 2009;15(24):7652–7)
Smoking-Related Gene Expression in Laser Capture–Microdissected Human Lung
Authors: Tan Xiang-Lin , Wang Tao , Xiong Shengli , Kumar Shalini V. , Han Weiguo , Spivack Simon D.
Published: December 2009

Purpose: Interindividual differences in quantitative expression could underlie a propensity for lung cancer. To determine precise individual gene expression signatures on a lung compartment–specific basis, we investigated the expression of carcinogen metabolism genes encoding cytochromes P450 (CYP) 1B1, 2A13, GSTP1, and a tumor suppressor gene p16 in laser capture–microdissected samples of human alveolar compartment (AC) and bronchial epithelial compartment (BEC) lung tissue from 62 smokers and nonsmokers.

Experimental Design: Tobacco exposure was determined by plasma nicotine, cotinine, and smoking history. Precise mRNA expression was determined using our RNA-specific qRT-PCR strategy, and correlated with detailed demographic and clinical characteristics.

Results: Several correlations of mRNA expression included (a) CYP1B1 in AC (positively with plasma nicotine level, P = 0.008; plasma cotinine level, P = 0.001), (b) GSTP1 in AC (positively with plasma cotinine level, P = 0.003), and (c) GSTP1 in BEC (negatively with smoke dose, P = 0.043; occupational risk, P = 0.019). CYP2A13 was rarely expressed in AC and not expressed in BEC. p16 expression was not correlated with any measured factor. For each gene, subjects showed expression that was individually concordant between these compartments. No clear association of mRNA expression with lung cancer risk was observed in this pilot analysis.

Conclusions: The association between lung mRNA expression and tobacco exposure implies that gene-tobacco interaction is a measurable quantitative trait, albeit with wide interindividual variation. Gene expression tends to be concordant for alveolar and bronchial compartments for these genes in an individual, controlling for proximate tobacco exposure. (Clin Cancer Res 2009;15(24):7562–70)
Characterizing the Clinical Relevance of an Embryonic Stem Cell Phenotype in Lung Adenocarcinoma
Authors: Stevenson Marvaretta , Mostertz William , Acharya Chaitanya , Kim William , Walters Kelli , Barry William , Higgins Kristin , Tuchman Sascha A. , Crawford Jeffrey , Vlahovic Gordana , Ready Neal , Onaitis Mark , Potti Anil
Published: December 2009

Purpose: Cancer cells possess traits reminiscent of those ascribed to normal stem cells. It is unclear whether these phenotypic similarities are the result of a common biological phenotype, such as regulatory pathways.

Experimental Design: Lung cancer cell lines with corresponding gene expression data and genes associated with an embryonic stem cell identity were used to develop a signature of embryonic stemness (ES) activity specific to lung adenocarcinoma. Biological characteristics were elucidated as a function of cancer biology/oncogenic pathway dysregulation. The ES signature was applied to three independent early-stage (I-IIIa) lung adenocarcinoma data sets with clinically annotated gene expression data. The relationship between the ES phenotype and cisplatin (current standard of care) sensitivity was evaluated.

Results: Pathway analysis identified specific regulatory networks [Ras (P = 0.0005), Myc (P = 0.0224), wound healing (P < 0.0001), chromosomal instability (P < 0.0001), and invasiveness (P < 0.0001)] associated with the ES phenotype. The prognostic relevance of the ES signature, as related to patient survival, was characterized in three cohorts [CALGB 9761 (n = 82; P = 0.0001), National Cancer Institute Director's Challenge Consortium (n = 442; P = 0.0002), and Duke (n = 45; P = 0.06)]. The ES signature was not prognostic in prostate, breast, or ovarian adenocarcinomas. Lung tumors (n = 569) and adenocarcinoma cell lines (n = 31) expressing the ES phenotype were more likely to be resistant to cisplatin (P < 0.0001 and P = 0.006, respectively).

Conclusions: Lung adenocarcinomas that share a common gene expression pattern with normal human embryonic stem cells were associated with decreased survival, increased biological complexity, and increased likelihood of resistance to cisplatin. This indicates the aggressiveness of these tumors. (Clin Cancer Res 2009;15(24):7553–61)
ABCC2, ABCC3, and ABCB1, but not CYP3A, Protect against Trabectedin-Mediated Hepatotoxicity
Authors: van Waterschoot Robert A.B. , Eman Rhandy M. , Wagenaar Els , van der Kruijssen Cornelia M.M. , Rosing Hilde , Beijnen Jos H. , Schinkel Alfred H.
Published: December 2009

Purpose: Trabectedin (Yondelis, ET-743) is a novel anticancer drug with potent activity against various tumors. However, dose-limiting hepatotoxicity was observed during clinical trials. Because recent reports have suggested that cytochrome P450 3A (CYP3A), as well as the drug transporters ABCB1, ABCC2, and ABCC3 might protect against trabectedin-mediated hepatotoxicity, we investigated the individual and combined roles of these detoxifying systems.

Experimental Design: Madin-Darby canine kidney cells expressing ABCC2 and ABCC3 were used to study in vitro trabectedin transport. We investigated the hepatotoxicity of trabectedin, and the plasma and liver levels of this drug and its metabolites in mice deficient for CYP3A, Abcb1a/1b, Abcc2, and/or Abcc3 after i.v. trabectedin administration.

Results: Trabectedin was transported by ABCC2 but only modestly by ABCC3. Contrary to our expectation, absence of CYP3A resulted in only a marginal increase in hepatotoxicity. Some hepatotoxicity was observed in Abcc2−/− mice, but very little in Abcb1a/1b−/− and Abcc3−/− mice. Strikingly, severe hepatotoxicity was found in Abcb1a/1b/Abcc2−/− and Abcc2/Abcc3−/− mice. However, hepatotoxicity was drastically decreased in Cyp3a/Abcb1a/1b/Abcc2−/− compared with Abcb1a/1b/Abcc2−/− mice. This suggests that the formation of CYP3A-specific metabolites is an important prerequisite for trabectedin-mediated hepatotoxicity. Further studies revealed that there is increased accumulation of metabolites of trabectedin, but not of trabectedin itself, in the livers of mice that lack Abcc2 but are CYP3A proficient.

Conclusions: Our data show that ABCB1, ABCC2, and ABCC3 have a profound and partially redundant function in protection from trabectedin-mediated hepatotoxicity, presumably by clearing the liver from hepatotoxic trabectedin metabolites that are primarily formed by CYP3A. (Clin Cancer Res 2009;15(24):7616–23)
Analysis of VHL Gene Alterations and their Relationship to Clinical Parameters in Sporadic Conventional Renal Cell Carcinoma
Authors: Young Alison C. , Craven Rachel A. , Cohen Dena , Taylor Claire , Booth Christopher , Harnden Patricia , Cairns David A. , Astuti Dewi , Gregory Walter , Maher Eamonn R. , Knowles Margaret A. , Joyce Adrian , Selby Peter J. , Banks Rosamonde E.
Published: December 2009

Purpose: This study aimed to carry out a comprehensive analysis of genetic and epigenetic changes of the von Hippel Lindau (VHL) gene in patients with conventional (clear cell) renal cell carcinoma and to determine their significance relative to clinicopathologic characteristics and outcome.

Experimental Design: The VHL status in 86 conventional renal cell carcinomas was determined by mutation detection, loss of heterozygosity (LOH), and promoter methylation analysis, extending our original cohort to a total of 177 patients. Data were analyzed to investigate potential relationships between VHL changes, clinical parameters, and outcome.

Results: LOH was found in 89.2%, mutation in 74.6%, and methylation in 31.3% of evaluable tumors; evidence of biallelic inactivation (LOH and mutation or methylation alone) was found in 86.0% whereas no involvement of VHL was found in only 3.4% of samples. Several associations were suggested, including those between LOH and grade, nodal status and necrosis, mutation and sex, and methylation and grade. Biallelic inactivation may be associated with better overall survival compared with patients with no VHL involvement, although small sample numbers in the latter group severely limit this analysis, which requires independent confirmation.

Conclusions: This study reports one of the highest proportions of conventional renal cell carcinoma with VHL changes, and suggests possible relationships between VHL status and clinical variables. The data suggest that VHL defects may define conventional renal cell carcinomas but the clinical significance of specific VHL alterations will only be clarified by the determination of their biological effect at the protein level rather than through genetic or epigenetic analysis alone. (Clin Cancer Res 2009;15(24):7582–92)
High Innate Production Capacity of Proinflammatory Cytokines Increases Risk for Death from Cancer: Results of the PROSPER Study
Authors: Trompet Stella , de Craen Anton J.M. , Mooijaart Simon , Stott David J. , Ford Ian , Sattar Naveed , Jukema Wouter , Westendorp Rudi G.J.
Published: December 2009

Purpose: Various lines of evidence suggest that proinflammatory factors may play a role in tumor growth and metastasis, the leading cause of cancer-related mortality. However, most evidence originates from animal models, only few human studies reported an association between proinflammatory cytokines and death from cancer. Here, we investigated the association between circulating levels and innate production capacity of proinflammatory cytokines and cancer incidence and mortality in the PROspective Study on Pravastatin in the Elderly at Risk (PROSPER).

Experimental Design: Circulating levels of interleukin 6 (IL-6) and C-reactive protein were measured in all 5,804 participants of the PROSPER study. The innate production capacity of IL-6, IL-1β, and tumor necrosis factor α (TNF-α) were measured in a random sample of 403 subjects.

Results: We showed that high circulating inflammatory markers were associated with an increased risk for cancer incidence and death from cancer during follow-up (all P < 0.05). Moreover, high innate proinflammatory cytokine production capacity is associated with an increased risk for death from cancer (all P < 0.04) but not with higher cancer incidence during follow-up (all P > 0.6).

Conclusions: High innate production capacity of proinflammatory cytokines is associated with an increased risk for death from cancer, probably because of increased tumor growth and metastasis. Because there was no association between innate production capacity and cancer incidence, the association between circulating levels and cancer incidence at least partially reflects reversed causality. (Clin Cancer Res 2009;15(24):7744–8)
Inhibition of Functional Hyaluronan-CD44 Interactions in CD133-positive Primary Human Ovarian Carcinoma Cells by Small Hyaluronan Oligosaccharides
Authors: Slomiany Mark G. , Dai Lu , Tolliver Lauren B. , Grass G. Daniel , Zeng Yiping , Toole Bryan P.
Published: December 2009

Purpose: CD44 is one of the most common markers used for identification of highly tumorigenic subpopulations of human carcinoma cells, but little is known about the function of CD44 or its major ligand, hyaluronan, in these cells. The purpose of this study was to investigate the involvement of hyaluronan and its interaction with CD44 in the properties of a tumorigenic subpopulation of primary ovarian carcinoma cells.

Experimental Design: A tumorigenic subpopulation was identified in ascites fluids from ovarian carcinoma patients by expression of high CD133 levels. Treatment with small hyaluronan oligosaccharides, which dissociate constitutive hyaluronan polymer-CD44 interactions, was used to test the importance of hyaluronan-CD44 interaction in assembly of multidrug and monocarboxylate transporters and receptor tyrosine kinases in the plasma membrane of cells with high CD133 levels, and in the tumorigenic capacity of the CD133-high subpopulation.

Results: Although total CD44 levels were similar in cells with high or low CD133 expression, CD44 was present in close association with transporters, receptor tyrosine kinases, and emmprin (CD147) in the plasma membrane of cells with high CD133 levels. Treatment with small hyaluronan oligosaccharides reduced association of the transporters and receptor tyrosine kinases with CD44 in the plasma membrane, diminished drug transporter activity, and inhibited i.p. tumorigenesis in these cells.

Conclusions: We conclude that hyaluronan-CD44 interaction plays an important role in the properties of highly tumorigenic cells by stabilizing oncogenic complexes in their plasma membrane, and that treatment with hyaluronan-CD44 antagonists provides a logical therapeutic approach for abrogating the properties of these cells. (Clin Cancer Res 2009;15(24):7593–601)
Tumor necrosis factor–related apoptosis-inducing ligand (TRAIL) and paclitaxel have cooperative in vivo effects against glioblastoma multiforme cells
Authors: Dorsey Jay F. , Mintz Akiva , Tian Xiaobing , Dowling Melissa L. , Plastaras John P. , Dicker David T. , Kao Gary D. , El-Deiry Wafik S.
Published: December 2009

Tumor necrosis factor–related apoptosis-inducing ligand (TRAIL) in conjunction with microtubule-targeting agents may be a promising novel anticancer treatment strategy. In vitro studies have suggested that relatively low concentrations of TRAIL enhance the lethality of paclitaxel (Taxol) against human cancer cells. The increased efficacy may be due to the triggering of caspase activation, resulting in mitotic checkpoint abrogation and catastrophe. We show here that wild-type p53 protects cells from caspase-dependent death induced by this therapeutic combination in vitro. We have now also developed an imaging-based model system to test the in vivo efficacy of combined TRAIL and Taxol, in which tumor growth and treatment response can be monitored noninvasively and in real-time. We further utilize bioluminescence, F18-fluorodeoxyglucose-positron emission tomography, and microscale computed tomography imaging to confirm the effects of combined treatment on tumors. These studies together provide the first in vivo confirmation that combined TRAIL plus paclitaxel results in better tumor control compared with either TRAIL or paclitaxel alone, and with no discernable increased normal tissue toxicity in the mouse. Interestingly, the in vivo antitumor response elicited by combined treatment was not affected by the p53 status of the tumor cells. These preclinical observations together suggest the therapeutic potential of combining TRAIL plus paclitaxel in cancer treatment, and support further preclinical and future clinical testing. [Mol Cancer Ther 2009;8(12):3285–95]
Inhibition of Y-box binding protein-1 slows the growth of glioblastoma multiforme and sensitizes to temozolomide independent O6-methylguanine-DNA methyltransferase
Authors: Gao Yuanyuan , Fotovati Abbas , Lee Cathy , Wang Michelle , Cote Gilbert , Guns Emma , Toyota Brian , Faury Damien , Jabado Nada , Dunn Sandra E.
Published: December 2009

Glioblastoma multiforme (GBM) is an aggressive type of brain tumor where <3% of newly diagnosed cases in the patients will survive >5 years. In adults, GBM is the most common type of brain tumor. It is rarer in children, where it constitutes ∼15% of all brain tumors diagnosed. These tumors are often invasive, making surgical resection difficult. Further, they can be refractory to current therapies such as temozolomide. The current dogma is that temozolomide resistance rests on the expression of O6-methylguanine-DNA methyltransferase (MGMT) because it cleaves methylated DNA adducts formed by the drug. Our laboratory recently reported that another drug resistance gene known as the Y-box binding protein-1 (YB-1) is highly expressed in primary GBM but not in normal brain tissues based on the evaluation of primary tumors. We therefore questioned whether GBM depend on YB-1 for growth and/or response to temozolomide. Herein, we report that YB-1 inhibition reduced tumor cell invasion and growth in monolayer as well as in soft agar. Moreover, blocking this protein ultimately delayed tumor onset in mice. Importantly, inhibiting YB-1 enhanced temozolomide sensitivity in a manner that was independent of MGMT in models of adult and pediatric GBM. In conclusion, inhibiting YB-1 may be a novel way to improve the treatment of GBM. [Mol Cancer Ther 2009;8(12):3276–84]
Natural product derivative Bis(4-fluorobenzyl)trisulfide inhibits tumor growth by modification of β-tubulin at Cys 12 and suppression of microtubule dynamics
Authors: Xu Wanhong , Xi Biao , Wu Jieying , An Haoyun , Zhu Jenny , Abassi Yama , Feinstein Stuart C. , Gaylord Michelle , Geng Baoqin , Yan Huifang , Fan Weimin , Sui Meihua , Wang Xiaobo , Xu Xiao
Published: December 2009

Bis(4-fluorobenzyl)trisulfide (BFBTS) is a synthetic molecule derived from a bioactive natural product, dibenzyltrisulfide, found in a subtropical shrub, Petiveria allieacea. BFBTS has potent anticancer activities to a broad spectrum of tumor cell lines with IC50 values from high nanomolar to low micromolar and showed equal anticancer potency between tumor cell lines overexpressing multidrug-resistant gene, MDR1 (MCF7/adr line and KBv200 line), and their parental MCF7 line and KB lines. BFBTS inhibited microtubule polymerization dynamics in MCF7 cells, at a low nanomolar concentration of 54 nmol/L, while disrupting microtubule filaments in cells at low micromolar concentration of 1 μmol/L. Tumor cells treated with BFBTS were arrested at G2-M phase, conceivably resulting from BFBTS-mediated antimicrotubule activities. Mass spectrometry studies revealed that BFBTS bound and modified β-tubulin at residue Cys12, forming β-tubulin-SS-fluorobenzyl. The binding site differs from known antimicrotubule agents, suggesting that BFBTS functions as a novel antimicrotubule agent. BFBTS at a dose of 25 mg/kg inhibited tumor growth with relative tumor growth rates of 19.91%, 18.5%, and 23.42% in A549 lung cancer, Bcap-37 breast cancer, and SKOV3 ovarian cancer xenografts, respectively. Notably, BFBTS was more potent against MDR1-overexpressing MCF7/adr breast cancer xenografts with a relative tumor growth rate of 12.3% than paclitaxel with a rate of 43.0%. BFBTS displays a novel antimicrotubule agent with potentials for cancer therapeutics. [Mol Cancer Ther 2009;8(12):3318–30]
Abcc2 (Mrp2), Abcc3 (Mrp3), and Abcg2 (Bcrp1) are the main determinants for rapid elimination of methotrexate and its toxic metabolite 7-hydroxymethotrexate in vivo
Authors: Vlaming Maria L. H. , van Esch Anita , Pala Zeliha , Wagenaar Els , van de Wetering Koen , van Tellingen Olaf , Schinkel Alfred H.
Published: December 2009

The multidrug transporters ABCC2, ABCC3, and ABCG2 can eliminate potentially toxic compounds from the body and have overlapping substrate specificities. To investigate the overlapping functions of Abcc2, Abcc3, and Abcg2 in vivo, we generated and characterized Abcc3;Abcg2−/− and Abcc2;Abcc3;Abcg2−/− mice. We subsequently analyzed the relative impact of these transport proteins on the pharmacokinetics of the anticancer drug methotrexate (MTX) and its main, toxic, metabolite 7-hydroxymethotrexate (7OH-MTX) after i.v. administration of MTX (50 mg/kg). Whereas in single and double knockout mice, the plasma and liver concentrations of MTX and 7OH-MTX decreased rapidly after MTX administration, in the Abcc2;Abcc3;Abcg2−/− mice, they remained very high. One hour after administration, 67% of the MTX dose was still present in livers of Abcc2;Abcc3;Abcg2−/− mice as MTX or 7OH-MTX versus 7% in wild-type, showing dramatic liver accumulation of these toxic compounds when Abcc2, Abcc3, and Abcg2 were all absent. Furthermore, the urinary and fecal excretion of the nephrotoxic metabolite 7OH-MTX were increased 27- and 7-fold, respectively, in Abcc2;Abcc3;Abcg2−/− mice. Thus, Abcc2, Abcc3, and Abcg2 together mediate the rapid elimination of MTX and 7OH-MTX after i.v. administration and can to a large extent compensate for each other's absence. This may explain why it is still comparatively safe to use a toxic drug such as MTX in the clinic, as the risk of highly increased toxicity due to dysfunctioning of ABCC2, ABCC3, or ABCG2 alone is limited. Nevertheless, cotreatment with possible inhibitors of ABCC2, ABCC3, and ABCG2 should be done with utmost caution when treating patients with methotrexate. [Mol Cancer Ther 2009;8(12):3350–9]
Antimitotic effect of the retinoid 4-oxo-fenretinide through inhibition of tubulin polymerization: a novel mechanism of retinoid growth–inhibitory activity
Authors: Appierto Valentina , Tiberio Paola , Cavadini Elena , Casalini Patrizia , Cappelletti Graziella , Formelli Franca
Published: December 2009

The retinoid 4-oxo-N-(4-hydroxyphenyl)retinamide (4-oxo-4-HPR), a metabolite of fenretinide (4-HPR) present in plasma of 4-HPR–treated patients, is very effective in inducing growth inhibition and apoptosis in several cancer cell lines. 4-Oxo-4-HPR and 4-HPR have different mechanisms of action because 4-oxo-4-HPR, unlike 4-HPR, causes marked cell accumulation in G2-M phase. Here, we investigated the molecular events involving 4-oxo-4-HPR–induced cell cycle perturbation in ovarian (A2780 and IGROV-1) and breast (T47D, estrogen receptor+ and BT-20, estrogen receptor-) cancer cells. 4-Oxo-4-HPR induced a delay of mitosis (with mitotic index increasing 5- to 6-fold in all cell lines) without progression beyond the anaphase, as shown by cyclin B1 expression. 4-Oxo-4-HPR induced multipolar spindle formation and phosphorylation of BUBR1, resulting in activation of the spindle checkpoint. Multipolar spindles were not due to impairment of pole-focusing process, loss of centrosome integrity, or modulation of the expression levels of molecules associated with spindle aberrations (Kif 1C, Kif 2A, Eg5, Tara, tankyrase-1, centractin, and TOGp). We show here that 4-oxo-4-HPR targets microtubules because, in treated cells, it interfered with the reassembly of cold-depolymerized spindle microtubules and decreased the polymerized tubulin fraction. In cell-free assays, 4-oxo-4-HPR inhibited tubulin polymerization (50% inhibition of microtubule assembly at 5.9 μmol/L), suggesting a direct molecular interaction with tubulin. In conclusion, by showing that 4-oxo-4-HPR causes mitotic arrest through antimicrotubule activities, we delineate a new molecular mechanism for a retinoid. [Mol Cancer Ther 2009;8(12):3360–8]
Tamoxifen Inhibits TRPV6 Activity via Estrogen Receptor–Independent Pathways in TRPV6-Expressing MCF-7 Breast Cancer Cells
Authors: Bolanz Katrin A. , Kovacs Gergely Gy. , Landowski Christopher P. , Hediger Matthias A.
Published: December 2009

The epithelial calcium channel TRPV6 is upregulated in breast carcinoma compared with normal mammary gland tissue. The selective estrogen receptor modulator tamoxifen is widely used in breast cancer therapy. Previously, we showed that tamoxifen inhibits calcium uptake in TRPV6-transfected Xenopus oocytes. In this study, we examined the effect of tamoxifen on TRPV6 function and intracellular calcium homeostasis in MCF-7 breast cancer cells transiently transfected with EYFP-C1-TRPV6. TRPV6 activity was measured with fluorescence microscopy using Fura-2. The basal calcium level was higher in transfected cells compared with nontransfected cells in calcium-containing solution but not in nominally calcium-free buffer. Basal influxes of calcium and barium were also increased. In transfected cells, 10 μmol/L tamoxifen reduced the basal intracellular calcium concentration to the basal calcium level of nontransfected cells. Tamoxifen decreased the transport rates of calcium and barium in transfected cells by 50%. This inhibitory effect was not blocked by the estrogen receptor antagonist, ICI 182,720. Similarly, a tamoxifen-induced inhibitory effect was also observed in MDA-MB-231 estrogen receptor–negative cells. The effect of tamoxifen was completely blocked by activation of protein kinase C. Inhibiting protein kinase C with calphostin C decreased TRPV6 activity but did not alter the effect of tamoxifen. These findings illustrate how tamoxifen might be effective in estrogen receptor–negative breast carcinomas and suggest that the therapeutic effect of tamoxifen and protein kinase C inhibitors used in breast cancer therapy might involve TRPV6-mediated calcium entry. This study highlights a possible role of TRPV6 as therapeutic target in breast cancer therapy. (Mol Cancer Res 2009;7(12):2000–10)
Emerging Roles of the EBF Family of Transcription Factors in Tumor Suppression
Authors: Liao Daiqing
Published: December 2009

Alterations in various developmental pathways are common themes in cancer. The early B-cell factors (EBF) are a family of four highly conserved DNA-binding transcription factors with an atypical zinc-finger and helix-loop-helix motif. They are involved in the differentiation and maturation of several cell lineages including B-progenitor lymphoblasts, neuronal precursors, and osteoblast progenitors. During B-cell development, EBF1 is required for the expression of Pax5, an essential factor for the production of antibody-secreting cells. Accumulating evidence indicates that genomic deletion of the EBF1 gene contributes to the pathogenesis, drug resistance, and relapse of B-progenitor acute lymphoblastic leukemia (ALL). Epigenetic silencing and genomic deletion of the EBF3 locus in chromosome 10q are very frequent in glioblastoma (GBM). Strikingly, the frequency of EBF3 loss in GBM is similar to that of the loss of Pten, a key suppressor of gliomagenesis. Cancer-specific somatic mutations were detected in EBF3 in GBM and in both EBF1 and EBF3 in pancreatic ductal adenocarcinoma. These missense mutations occur in the DNA-binding domain or the conserved IPT/TIG domain, suggesting that they might disrupt the functions of these two proteins. Functional studies revealed that EBF3 represses the expression of genes required for cell proliferation [e.g., cyclins and cyclin-dependent kinases (CDK)] and survival (e.g., Mcl-1 and Daxx) but activates those involved in cell cycle arrest (e.g., p21 and p27), leading to growth suppression and apoptosis. Therefore, EBFs represent new tumor suppressors whose inactivation blocks normal development and contributes to tumorigenesis of diverse types of human cancer. (Mol Cancer Res 2009;7(12):1893–901)
Conservative Management in Three Cases of Prenatally Recognized Splenic Cyst Using 2D, 3D, Multi-Slice and Doppler Ultrasonography
Authors: Dankovcik Robert , Urdzik Peter , Lazar Igor , Gresova Andrea , Radonak Jozef , Jirasek Jan E. , Kucera Eduard , Feyereisl Jaroslav , Dudas Marek
Published: December 2009

The aetiology, differential diagnosis and management strategies of the foetal spleen affected with a cystic lesion are discussed. In the current literature, there are very few reports that relate to antenatally diagnosed splenic cyst. Our study presents 3 case reports that were first suspected due to anisoechogenic structures detected during routine ultrasonographic examination at the 27th, 31st and 34th weeks of gestation. All 3 cases were further characterized by the lack of pathological power Doppler findings inside and around the lesions, and were morphologically refined by prenatal 3D ultrasound imaging. All findings were reconfirmed postnatally. No complications such as cyst expansion, subcapsular bleeding or acute abdomen have developed, and all 3 cystic lesions have regressed spontaneously after birth.
Treatment of Neurogenic Detrusor Overactivity with Botulinum Toxin A: The First Seven Years
Authors: Stoehrer Manfred , Wolff Andreas , Kramer Guus , Steiner Rainer , Löchner-Ernst Dieter , Leuth Dirk , Steude Ute , Ruebben Herbert
Published: December 2009

Introduction: This retrospective study describes the results of botulinum toxin A detrusor injections following a fixed protocol in 216 patients with untreatable neurogenic detrusor overactivity and incontinence. A comparison is made between the two preparations currently available, and the efficacy of multiple treatments is studied. Patients and Methods: Botox® 300 MU (mouse units) or Dysport® 750 MU were injected into the detrusor wall in 365 sessions in 216 patients. The average age of the 144 men and 72 women was 32.3 years. Patients were investigated before treatment and at 6 weeks and 6 months after treatment. Maximal detrusor pressure, detrusor compliance, reflex volume and cystometric capacity were recorded. Use of anticholinergics and patient satisfaction were ascertained from questionnaires. Appropriate statistics were applied. Results: All urodynamic parameters improved. The use of anticholinergics decreased substantially. No differences were noted between the two preparations. The incontinence situation improved markedly. The effect of the treatment was noted after about 2 weeks and lasted for about 9 months. Conclusions: Botulinum toxin A treatment in neurogenic detrusor overactivity patients is effective, long-lasting and repeatable. The treatment is minimally invasive and might be considered as an alternative to high-dosage anticholinergic medication.
Repeat Transobturator Tape after Failed Mid-Urethral Sling Procedure: Follow-Up with Questionnaire-Based Assessment
Authors: Van Baelen Anthony A.A. , Delaere Karl P.J.
Published: December 2009

Objective: To determine if repeat transobturator tape (TOT) is feasible after failed initial synthetic mid-urethral sling (MUS) for stress urinary incontinence, and to ascertain objective physician-determined outcome as well as subjective questionnaire-based outcome for this procedure. Patients and Methods: Between February 2005 and February 2008, a total of 21 patients underwent repeat TOT procedure after failed sling treatment. Initial sling procedures were all synthetic MUS, i.e. tension-free vaginal tape in 5 cases and TOT in 16 cases. Results: At a mean follow-up of 16 months, physician-determined cure was achieved in 55% of patients, improvement in 15% and failure in 30%. Outcome deduced from the International Consultation on Incontinence Questionnaire at a mean follow-up of 17 months showed 53% of patients to be cured and 5% of patients to be improved, but failure was noted in 42% of patients. Conclusions: Repeat TOT after failed synthetic MUS treatment is a feasible procedure with minor morbidity. Repeat TOT provides a reasonable physician-determined success rate, but a lower patient self-reported success rate can be deduced from questionnaires. The transobturator approach seems to show poorer outcomes than the retropubic approach in repeat sling surgery.
Outcome of Percutaneous Nephrolithotomy in Children Having Complex Stones
Authors: Gonen Murat , Turunc Tahsin , Ozturk Bulent , Aygun Cem , Ozkardes Hakan
Published: December 2009

Objectives: To review our experiences with percutaneous nephrolithotomy in children with complex renal calculi. Patients and Methods: We retrospectively analyzed the records of 31 children with complex renal calculi who were treated by percutaneous nephrolithotomy at 2 hospitals of our university between June 2003 and June 2008. The mean age of the patients was 10.4 years (range 22 months to 15 years). Three patients were aged ≤5 years. Stone clearance and complications were recorded. Results: The mean operating time (time from insertion of the ureteral catheter to placement of a nephrostomy tube) was 87.4 (range 50–180) min. In 2 patients the procedures were staged because of a large residual stone load. The extent of percutaneous tract dilation was undertaken taking patient age and the presence of hydronephrosis into consideration. Complete stone clearance with percutaneous nephrolithotomy was achieved in 21 (67.7%) of 31 patients. Adding extracorporeal lithotripsy increased total clearance to 24/31 (77.4%). The most common complication was bleeding that necessitated blood transfusion (7/31, 22.5%). Conclusion: Percutaneous nephrolithotomy is as safe and effective in children as it is in adults. The clearance rate can be increased with dual therapy. Tract dilation should be tailored according to patient age and the extent of hydronephrosis.
Diagnosis and Treatment of Adrenal Tumors: A Single-Center Experience with 238 Cases
Authors: Gomha Abdul-Monem , Osman Yasser , El-Mekresh Mohsen , Abou El-Ghar Mohamed , Eraky Ibrahim
Published: December 2009

Objective: It was the aim of this study to review and analyze clinical data on the diagnosis and management of patients with adrenal masses. Patients and Methods: Between 1976 and 2005, 238 patients admitted to our institute with adrenal masses were reviewed. Incidence, clinical features, imaging technique findings, surgical approaches, morbidity and mortality, as well as pathological diagnoses were reported. Results: The series comprised 134 males and 104 females (mean age 33.3 ± 20.3 years). Right-sided masses were more common (63.4%), with a mean size of 7.7 ± 4 cm. Pain was the most frequent presenting symptom (53.4%), while 62 (26%) had a functional tumor. Incidentaloma was diagnosed in 49 patients (20.6%). Both computed tomography and magnetic resonance imaging showed a high diagnostic yield (sensitivities of 98.9 and 100%, respectively). Open adrenalectomy was performed in 153 patients (64.3%), while a laparoscopic approach was employed in 53 patients (22.3%). The intraoperative complication rate was 14.7%, the postoperative complication rate 6.1% and perioperative mortality 1.7%. Most of the excised masses were pheochromocytomas (26.4%). Conclusions: Computed tomography is recommended as the first diagnostic modality to define and characterize adrenal masses. Laparoscopic adrenalectomy is currently replacing open surgery as the standard surgical management of adrenal masses.