bluuebunny/crossref_metadata_2025 huggingface dataset:
Heparanase Is Involved in Angiogenesis in Esophageal Cancer through Induction of Cyclooxygenase-2
Authors: Okawa Takaomi , Naomoto Yoshio , Nobuhisa Tetsuji , Takaoka Munenori , Motoki Takayuki , Shirakawa Yasuhiro , Yamatsuji Tomoki , Inoue Hiroyasu , Ouchida Mamoru , Gunduz Mehmet , Nakajima Motowo , Tanaka Noriaki
Published: March 2006

Purpose: Both heparanase and cyclooxygenase-2 (COX-2) are thought to play critical roles for tumor malignancy, including angiogenesis, although it is unknown about their relationship with each other in cancer progression. We hypothesized that they may link to each other on tumor angiogenesis.

Experimental Design: The expressions of heparanase and COX-2 in 77 primary human esophageal cancer tissues were assessed by immunohistochemistry to do statistical analysis for the correlation between their clinicopathologic features, microvessel density, and survival of those clinical cases. Human esophageal cancer cells were transduced with heparanase cDNA and used for reverse transcription-PCR and Western blot to determine the expression of heparanase and COX-2. COX-2 promoter vector and its deletion/mutation constructs were also used along with transduction of heparanase cDNA for luciferase assay.

Results: Heparanase and COX-2 protein expression exhibited a similar pattern in esophageal tumor tissues, and their expression correlated with tumor malignancy and poor survival. Their expression also revealed a significant correlation with high intratumoral microvessel density. Up-regulation of COX-2 mRNA and protein was observed in esophageal cancer cells transfected with heparanase cDNA. COX-2 promoter was activated after heparanase cDNA was transduced and the deletion/mutation of three transcription factor (cyclic AMP response element, nuclear factor-κB, and nuclear factor-interleukin-6) binding elements in COX-2 promoter strongly suppressed its activity.

Conclusion: Our results suggest that heparanase may play a novel role for COX-2-mediated tumor angiogenesis.
Expression Profiling of Mucinous Tumors of the Ovary Identifies Genes of Clinicopathologic Importance
Authors: Wamunyokoli Fred W. , Bonome Tomas , Lee Ji-Young , Feltmate Colleen M. , Welch William R. , Radonovich Mike , Pise-Masison Cindy , Brady John , Hao Ke , Berkowitz Ross S. , Mok Samuel , Birrer Michael J.
Published: March 2006

Purpose: To elucidate the molecular mechanisms contributing to the unique clinicopathologic characteristics of mucinous ovarian carcinoma, global gene expression profiling of mucinous ovarian tumors was carried out.

Experimental Design: Gene expression profiling was completed for 25 microdissected mucinous tumors [6 cystadenomas, 10 low malignant potential (LMP) tumors, and 9 adenocarcinomas] using Affymetrix U133 Plus 2.0 oligonucleotide microarrays. Hierarchical clustering and binary tree prediction analysis were used to determine the relationships among mucinous specimens and a series of previously profiled microdissected serous tumors and normal ovarian surface epithelium. PathwayAssist software was used to identify putative signaling pathways involved in the development of mucinous LMP tumors and adenocarcinomas.

Results: Comparison of the gene profiles between mucinous tumors and normal ovarian epithelial cells identified 1,599, 2,916, and 1,765 differentially expressed in genes in the cystadenomas, LMP tumors, and adenocarcinomas, respectively. Hierarchical clustering showed that mucinous and serous LMP tumors are distinct. In addition, there was a close association of mucinous LMP tumors and adenocarcinomas with serous adenocarcinomas. Binary tree prediction revealed increased heterogeneity among mucinous tumors compared with their serous counterparts. Furthermore, the cystadenomas coexpressed a subset of genes that were differentially regulated in LMP and adenocarcinoma specimens compared with normal ovarian surface epithelium. PathwayAssist highlighted pathways with expression of genes involved in drug resistance in both LMP and adenocarcinoma samples. In addition, genes involved in cytoskeletal regulation were specifically up-regulated in the mucinous adenocarcinomas.

Conclusions: These data provide a useful basis for understanding the molecular events leading to the development and progression of mucinous ovarian cancer.
Differential Metastasis Inhibition by Clinically Relevant Levels of Heparins—Correlation with Selectin Inhibition, Not Antithrombotic Activity
Authors: Stevenson Jennifer L. , Choi Sharon H. , Varki Ajit
Published: March 2006

Purpose: Unfractionated heparin reduces metastasis in many murine models. Multiple mechanisms are proposed, particularly anticoagulation and/or inhibition of P-selectin and L-selectin. However, the doses used are not clinically tolerable and other heparins are now commonly used. We studied metastasis inhibition by clinically relevant levels of various heparins and investigated the structural basis for selectin inhibition differences.

Experimental Design: Five clinically approved heparins were evaluated for inhibition of P-selectin and L-selectin binding to carcinoma cells. Pharmacokinetic studies determined optimal dosing for clinically relevant anticoagulant levels in mice. Experimental metastasis assays using carcinoma and melanoma cells investigated effects of a single injection of various heparins. Heparins were compared for structural relationships to selectin inhibition.

Results: One (Tinzaparin) of three low molecular weight heparins showed increased selectin inhibitory activity, and the synthetic pentasaccharide, Fondaparinux, showed none when normalized to anticoagulant activity. Experimental metastasis models showed attenuation with unfractionated heparin and Tinzaparin, but not Fondaparinux, at clinically relevant anticoagulation levels. Tinzaparin has a small population of high molecular weight fragments not present in other low molecular weight heparins, enriched for selectin inhibitory activity.

Conclusions: Heparin can attenuate metastasis at clinically relevant doses, likely by inhibiting selectins. Equivalent anticoagulation alone with Fondaparinux is ineffective. Clinically approved heparins have differing abilities to inhibit selectins, likely explained by size distribution. It should be possible to size fractionate heparins and inhibit selectins at concentrations that do not have a large effect on coagulation. Caution is also raised about the current preference for smaller heparins. Despite equivalent anticoagulation, hitherto unsuspected benefits of selectin inhibition in various clinical circumstances may be unwittingly discarded.
Schedule-Dependent Drug Effects of Oral 5-Iodo-2-Pyrimidinone-2′-Deoxyribose as an In vivo Radiosensitizer in U251 Human Glioblastoma Xenografts
Authors: Seo Yuji , Yan Tao , Schupp Jane E. , Radivoyevitch Tomas , Kinsella Timothy J.
Published: March 2006

Purpose: 5-Iodo-2-pyrimidinone-2′-deoxyribose (IPdR) is an oral prodrug of 5-iodo-2′-deoxyuridine (IUdR), an in vitro/in vivo radiosensitizer. IPdR can be rapidly converted to IUdR by a hepatic aldehyde oxidase. Previously, we found that the enzymatic conversion of IPdR to IUdR could be transiently reduced using a once daily (q.d.) treatment schedule and this may affect IPdR-mediated tumor radiosensitization. The purpose of this study is to measure the effect of different drug dosing schedules on tumor radiosensitization and therapeutic index in human glioblastoma xenografts.

Experimental Design: Three different IPdR treatment schedules (thrice a day, t.i.d.; every other day, q.o.d.; every 3rd day, q.3.d.), compared with a q.d. schedule, were analyzed using athymic nude mice with human glioblastoma (U251) s.c. xenografts. Plasma pharmacokinetics, IUdR-DNA incorporation in tumor and normal proliferating tissues, tumor growth delay following irradiation, and body weight loss were used as end points.

Results: The t.i.d. schedule with the same total daily doses as the q.d. schedule (250, 500, or 1,000 mg/kg/d) improved the efficiency of IPdR conversion to IUdR. As a result, the percentage of IUdR-DNA incorporation was higher using the t.i.d. schedule in the tumor xenografts as well as in normal small intestine and bone marrow. Using a fixed dose (500 mg/kg) per administration, the q.o.d. and q.3.d. schedules also showed greater IPdR conversion than the q.d. schedule, related to a greater recovery of hepatic aldehyde oxidase activity prior to the next drug dosing. In the tumor regrowth assay, all IPdR treatment schedules showed significant increases of regrowth delays compared with the control without IPdR (q.o.d., 29.4 days; q.d., 29.7 days; t.i.d., 34.7 days; radiotherapy alone, 15.7 days). The t.i.d. schedule also showed a significantly enhanced tumor growth delay compared with the q.d. schedule. Additionally, the q.o.d. schedule resulted in a significant reduction in systemic toxicity.

Conclusions: The t.i.d. and q.o.d. dosing schedules improved the efficiency of enzymatic activation of IPdR to IUdR during treatment and changed the extent of tumor radiosensitization and/or systemic toxicity compared with a q.d. dosing schedule. These dosing schedules will be considered for future clinical trials of IPdR-mediated human tumor radiosensitization.
Genome-Wide Screening of Genomic Alterations and Their Clinicopathologic Implications in Non–Small Cell Lung Cancers
Authors: Kim Tae-Min , Yim Seon-Hee , Lee Jung-Sook , Kwon Mi-Seon , Ryu Jae-Wook , Kang Hyun-Mi , Fiegler Heike , Carter Nigel P. , Chung Yeun-Jun
Published: March 2006

Purpose: Although many genomic alterations have been observed in lung cancer, their clinicopathologic significance has not been thoroughly investigated. This study screened the genomic aberrations across the whole genome of non–small cell lung cancer cells with high-resolution and investigated their clinicopathologic implications.

Experimental Design: One-megabase resolution array comparative genomic hybridization was applied to 29 squamous cell carcinomas and 21 adenocarcinomas of the lung. Tumor and normal tissues were microdissected and the extracted DNA was used directly for hybridization without genomic amplification. The recurrent genomic alterations were analyzed for their association with the clinicopathologic features of lung cancer.

Results: Overall, 36 amplicons, 3 homozygous deletions, and 17 minimally altered regions common to many lung cancers were identified. Among them, genomic changes on 13q21, 1p32, Xq, and Yp were found to be significantly associated with clinical features such as age, stage, and disease recurrence. Kaplan-Meier survival analysis revealed that genomic changes on 10p, 16q, 9p, 13q, 6p21, and 19q13 were associated with poor survival. Multivariate analysis showed that alterations on 6p21, 7p, 9q, and 9p remained as independent predictors of poor outcome. In addition, significant correlations were observed for three pairs of minimally altered regions (19q13 and 6p21, 19p13 and 19q13, and 8p12 and 8q11), which indicated their possible collaborative roles.

Conclusions: These results show that our approach is robust for high-resolution mapping of genomic alterations. The novel genomic alterations identified in this study, along with their clinicopathologic implications, would be useful to elucidate the molecular mechanisms of lung cancer and to identify reliable biomarkers for clinical application.
Patupilone Induced Vascular Disruption in Orthotopic Rodent Tumor Models Detected by Magnetic Resonance Imaging and Interstitial Fluid Pressure
Authors: Ferretti Stephane , Allegrini Peter R. , O'Reilly Terence , Schnell Christian , Stumm Michael , Wartmann Markus , Wood Jeanette , McSheehy Paul M.J.
Published: March 2006

Purpose: Evaluation of vascular disruptive activity in orthotopic models as potential surrogate biomarkers of tumor response to the microtubule-stabilizing agent patupilone.

Experimental Design: Mice bearing metastatic B16/BL6 melanoma and rats bearing mammary BN472 tumors received vehicle or efficacious patupilone doses (4 and 0.8-1.5 mg/kg i.v., respectively). Tumor vascularity assessment by dynamic contrast-enhanced or dynamic susceptibility contrast magnetic resonance imaging and interstitial fluid pressure (IFP) occurred at baseline, 2 days (mice and rats), and 6 days (rats) after treatment and were compared with histologic measurements and correlated with tumor response.

Results: In B16/BL6 metastases, patupilone (4 mg/kg) induced a 21 ± 5% decrease (P < 0.001) in tumor blood volume and a 32 ± 15% decrease (P = 0.02) in IFP after 2 days and reduced tumor growth and vessel density (>42%) after 2 weeks (P ≤ 0.014). Patupilone dose-dependently inhibited BN472 tumor growth (day 6) and reduced IFP on days 2 and 6 (−21% to −70%), and the percentage change in IFP correlated (P < 0.01) with the change in tumor volume. In both models, histology and vascular casts confirmed decreases in tumor blood volume. One patupilone (0.8 mg/kg) administration decreased (P < 0.01) tumor IFP (54 ± 4%), tumor blood volume (50 ± 6%), and vessel diameter (40 ± 11%) by day 6 but not the apparent diffusion coefficient, whereas histology showed that apoptosis was increased 2.4-fold and necrosis was unchanged. Apoptosis correlated negatively (P < 0.001) with IFP, tumor blood volume, and tumor volume, whereas tumor blood volume and IFP were correlated positively (P = 0.0005).

Conclusions: Vascular disruptive effects of patupilone were detected in situ using dynamic contrast-enhanced or dynamic susceptibility contrast magnetic resonance imaging and IFP. Changes in IFP preceded and correlated with tumor response, suggesting that IFP may be a surrogate biomarker for patupilone efficacy.
Mcl-1, Vascular Endothelial Growth Factor-R2, and 14-3-3σ Expression Might Predict Primary Response against Radiotherapy and Chemotherapy in Patients with Locally Advanced Squamous Cell Carcinomas of the Head and Neck
Authors: Erovic Boban M. , Pelzmann Martina , Grasl Matthäus Ch. , Pammer Johannes , Kornek Gabriela , Brannath Werner , Selzer Edgar , Thurnher Dietmar
Published: March 2006

Purpose: This study was done to explore whether the expression of a selected set of proteins could predict primary response to radiotherapy or concomitant radiotherapy and chemotherapy in patients with advanced head and neck cancer.

Experimental Design: Forty-three pretreatment tumor biopsies were taken during diagnostic panendoscopy and examined for Mcl-1, vascular endothelial growth factor (VEGF)-R2, CD9, and 14-3-3σ expression by immunohistochemistry. Forty-three patients underwent primary radiotherapy, of which, 29 patients received concomitant chemotherapy (low dose daily cisplatin, mitomycin C bolus). The primary end-point was locoregional tumor control 6 months after completion of radiotherapy. Mcl-1, VEGF-R2, CD9, and 14-3-3σ expression were correlated with patients' primary response to radiotherapy and chemotherapy and with established clinicopathologic variables.

Results: Thirty complete and 13 partial responses were observed in our patient group. High expression levels of Mcl-1 (P = 0.021), VEGF-R2 (P = 0.032), and 14-3-3σ (P = 0.013), but not of CD9, in tumor biopsies was correlated with complete response. Overexpression of at least two of the three aforementioned proteins in pretreatment biopsies predicted—with a likelihood of 80%—whether a patient would achieve complete response to radiotherapy and chemotherapy. However, if only one of these proteins is overexpressed, there is a likelihood of 84.6% that this patient would not completely respond to therapy.

Conclusion: Determining the expression levels of Mcl-1, VEGF-R2, and 14-3-3σ may be helpful in predicting the early clinical response in head and neck tumor patients receiving primary radiotherapy and chemotherapy and may further allow a pretherapeutic selection of patients.
Curcumin Suppresses the Paclitaxel-Induced Nuclear Factor-κB Pathway in Breast Cancer Cells and Inhibits Lung Metastasis of Human Breast Cancer in Nude Mice
Authors: Aggarwal Bharat B. , Shishodia Shishir , Takada Yasunari , Banerjee Sanjeev , Newman Robert A. , Bueso-Ramos Carlos E. , Price Janet E.
Published: March 2006

Currently, there is no effective therapy for metastatic breast cancer after surgery, radiation, and chemotherapy have been used against the primary tumor. Because curcumin suppresses nuclear factor-κB (NF-κB) activation and most chemotherapeutic agents activate NF-κB that mediates cell survival, proliferation, invasion, and metastasis, we hypothesized that curcumin would potentiate the effect of chemotherapy in advanced breast cancer and inhibit lung metastasis. We tested this hypothesis using paclitaxel (Taxol)-resistant breast cancer cells and a human breast cancer xenograft model. As examined by electrophoretic mobility gel shift assay, paclitaxel activated NF-κB in breast cancer cells and curcumin inhibited it; this inhibition was mediated through inhibition of IκBα kinase activation and IκBα phosphorylation and degradation. Curcumin also suppressed the paclitaxel-induced expression of antiapoptotic (XIAP, IAP-1, IAP-2, Bcl-2, and Bcl-xL), proliferative (cyclooxygenase 2, c-Myc, and cyclin D1), and metastatic proteins (vascular endothelial growth factor, matrix metalloproteinase-9, and intercellular adhesion molecule-1). It also enhanced apoptosis. In a human breast cancer xenograft model, dietary administration of curcumin significantly decreased the incidence of breast cancer metastasis to the lung and suppressed the expression of NF-κB, cyclooxygenase 2, and matrix metalloproteinase-9. Overall, our results indicate that curcumin, which is a pharmacologically safe compound, has a therapeutic potential in preventing breast cancer metastasis possibly through suppression of NF-κB and NF-κB–regulated gene products.
BMS-345541 Targets Inhibitor of κB Kinase and Induces Apoptosis in Melanoma: Involvement of Nuclear Factor κB and Mitochondria Pathways
Authors: Yang Jinming , Amiri Katayoun I. , Burke James R. , Schmid Johannes A. , Richmond Ann
Published: March 2006

Purpose: Constitutive activation of inhibitor of κB kinase (IKK) confers melanoma resistance to apoptosis and chemotherapy. Whether IKK is able to serve as a therapeutic target in melanoma is unknown. We explored the possibility of exploiting IKK as a therapeutic target in melanoma by using BMS-345541, a novel compound with a highly selective IKKβ inhibitory activity, to trigger melanoma cell apoptosis.

Experimental Design: Three human melanoma cell lines (SK-MEL-5, Hs 294T, and A375), all of which have high constitutive IKK activities, served as in vitro and in vivo melanoma models for treatment with BMS-345541. Two known antitumor drugs (temozolomide and bortezomib) were used as parallel controls for evaluation of the therapeutic efficiency and toxicity of BMS-345541. The effects of BMS-345541 on nuclear factor κB (NF-κB) signaling and on the apoptosis machinery were investigated.

Results: Inhibition of constitutive IKK activity by BMS-345541 resulted in the reduction of NF-κB activity, CXCL1 chemokine secretion by cultured melanoma cells and melanoma cell survival in vitro and in vivo. The effect of BMS-345541 on tumor cell growth was through mitochondria-mediated apoptosis, based on the release of apoptosis-inducing factor, dissipation of mitochondrial membrane potential, and reduced ratio of B cell lymphoma gene-2 (Bcl-2)/Bcl-associated X protein (Bax) in mitochondria. The BMS-345541 execution of apoptosis was apoptosis-inducing factor–dependent, but largely caspase-independent.

Conclusion: BMS-345541 down-regulation of IKK activity results in mitochondria-mediated apoptosis of tumor cells because the programmed cell death machinery in melanoma cells is highly regulated by NF-κB signaling. Therefore, IKK may serve as a potential target for melanoma therapy.
Evaluation of the Antitumor Efficacy, Pharmacokinetics, and Pharmacodynamics of the Histone Deacetylase Inhibitor Depsipeptide in Childhood Cancer Models In vivo
Authors: Graham Claire , Tucker Chandra , Creech Jeremy , Favours Edward , Billups Catherine A. , Liu Tiebin , Fouladi Maryam , Freeman Burgess B. , Stewart Clinton F. , Houghton Peter J.
Published: March 2006

Purpose: Histone acetyltransferases and histone deacetylases (HDAC) control the acetylation state of histones and other proteins regulating transcription and protein function. Several structurally diverse HDAC inhibitors have been developed as cancer therapeutic agents and in vitro have been shown to cause differentiation, cell cycle arrest, or apoptosis. Here, we have evaluated depsipeptide, a natural tetrapeptide HDAC inhibitor, against a panel of pediatric solid tumor models in vivo and evaluated pharmacokinetic and pharmacodynamic variables with tumor sensitivity.

Experimental Design: Depsipeptide was administered at the maximum tolerated dose (4.4 mg/kg administered every 7 days × 3 i.v. repeated q21d for a total of two cycles) to scid mice bearing 39 independently derived childhood tumors (9 brain tumors, 11 kidney cancers, 9 rhabdomyosarcomas, 3 neuroblastomas, and 7 osteosarcomas). Pharmacokinetic variables were determined, as were changes in histone and p53 acetylation, induction of p53 and p53 genotype, and alterations in Akt phosphorylation.

Results: Of 39 tumors evaluated, three showed objective tumor regressions [two brain tumors (primitive neuroectodermal tumor and atypical teratoid malignant rhabdoid tumor) and one Wilms' tumor]. Depsipeptide inhibited growth of many tumor lines but achieved stable disease (<25% increase in volume during treatment cycle 1) in only two tumor models (anaplastic astrocytoma, two rhabdomyosarcomas, and a Wilms' tumor). Pharmacokinetic analysis showed that the population estimated AUC0-24 was 1,123 ng h/mL, similar to the exposure following 13 mg/m2 in ongoing phase I trials. Pharmacodynamic changes in histone acetylation (H2A, H2B, H3, and H4) in three depsipeptide-sensitive and three intrinsically resistant tumors followed a similar pattern; maximal increases in histone acetylation occurred at 8 hours and were elevated for up to 96 hours. In two sensitive tumor lines, IRS56 and BT27 (both wild-type p53) p53 increased in treated tumors being maximal at 8 hours and associated with induction of p21cip1, whereas p53 was stable in tumors with mutant p53. Sensitivity to depsipeptide did not correlate with p53 genotype, p53 acetylation, cleaved poly(ADP-ribose) polymerase, or phosphorylation of Akt (Ser473).

Conclusions: Our results show that depsipeptide inhibits its target in vivo causing increased histone acetylation; however, this does not correlate with drug sensitivity. The relatively low objective response rate [3 of 39 (8%) tumor lines showing greater than or equal to partial response and 4 (10%) stable disease] administered at dose levels that give clinically relevant drug exposures suggests that as a single agent depsipeptide may have limited clinical utility against pediatric solid tumors in a first-line setting.
The Use of Genetic Markers to Determine Risk for Prostate Cancer at Prostate Biopsy
Authors: Nam Robert K. , Zhang William W. , Jewett Michael A.S. , Trachtenberg John , Klotz Laurence H. , Emami Marjan , Sugar Linda , Sweet Joan , Toi Ants , Narod Steven A.
Published: March 2006

Purpose: We examined a panel of 13 polymorphisms in 13 different genes to determine whether specific genotypes can help predict prostate cancer at the time of biopsy among men prescreened with prostate-specific antigen and digital rectal exam.

Experimental Design: We examined 2,088 consecutive men who were referred for prostate biopsy from 1997 to 2003. Thirteen genes were examined, including TNF308, GSTT1, KLK2, endostatin, MCRA, MCRV, tyrosinase, MSR1, CHK2, RNasel, HOGG1-326, HOGG1-11657, and HRAS1. Odds ratio for detection of prostate cancer were adjusted for age, race, prostate-specific antigen, digital rectal exam, family history of prostate cancer, and urinary symptoms.

Results: Of the 2,088 men, 996 (47.7%) had cancer detected. Four genes (TNF308, GSTT1, KLK2, and HOGG1-326) were significantly associated with prostate cancer. The adjusted odds ratios (OR) for prostate cancer for patients with the AA genotype of the TNF308 gene was 1.92 [95% confidence interval (95% CI), 1.0-1.5, P = 0.05], compared with those with the GG genotype, and for patients with the TT genotype of the KLK2 gene, the OR was 1.5 (95% confidence interval, 1.0-2.2, P = 0.04), compared with the CC genotype. The OR for patients with a homozygous deletion of the GSTT1 gene was 0.81 (95% CI, 0.6-1.0, P = 0.06) compared with those with the deletion, and the OR for patients with the GG genotype of the HOGG1-326 gene was 0.68 (95% CI, 0.5-1.0, P = 0.05) compared with the CC genotype. Patients who had all four alleles that were positively associated with prostate cancer had an OR of 9.33 (95% CI, 2.4-35.8, P = 0.0005) for prostate cancer compared with patients with alleles that were negatively associated with prostate cancer.

Conclusions: Of the 13 polymorphisms, two were found to be positively associated with prostate cancer (TNF308 and KLK2) and two were negatively associated with prostate cancer (GSTT1 and HOGG1-326). Future studies are required to confirm these results.
Histone Deacetylase Inhibitor–Mediated Radiosensitization of Human Cancer Cells: Class Differences and the Potential Influence of p53
Authors: Kim In Ah , Shin Jin Hee , Kim Il Han , Kim Jin Ho , Kim Jae Sung , Wu Hong Gyun , Chie Eui Kyu , Ha Sung Whan , Park Charn Il , Kao Gary D.
Published: March 2006

Histone deacetylase inhibitors (HDI) are emerging as potentially useful components of the anticancer armamentarium and as useful tools to dissect mechanistic pathways. HDIs that globally inhibit histone deacetylases (HDAC) have radiosensitizing effects, but the relative contribution of specific HDAC classes remains unclear. Newly characterized HDIs are now available that preferentially inhibit specific HDAC classes, including SK7041 (inhibits class I HDACs) and splitomicin (inhibits class III HDACs). We investigated in human cancer cells the relative radiosensitizations that result from blocking specific HDAC classes. We found that trichostatin A (TSA; inhibitor of both class I and II HDACs) was the most effective radiosensitizer, followed by the class I inhibitor SK7041, whereas splitomicin (inhibitor of class III) had least effect. Interestingly, radiosensitization by TSA in cell lines expressing p53 was more pronounced than in isogenic lines lacking p53. Radiosensitization of cells expressing p53 by TSA was reduced by pifithrin-α, a small-molecule inhibitor of p53. In contrast, the radiosensitization by TSA of cells expressing low levels of p53 was enhanced by transfection of wild-type p53–expressing vector or pretreatment with leptomycin B, an inhibitor of nuclear export that increased intracellular levels of p53. These effects on radiosensitization were respectively muted or not seen in cells treated with SK7041 or splitomicin. To our knowledge, this may be among the first systematic investigations of the comparative anticancer effects of inhibiting specific classes of HDACs, with results suggesting differences in the degrees of radiosensitization, which in some cell lines may be influenced by p53 expression.
Phase I/II Study of 19-nor-1α-25-Dihydroxyvitamin D2 (Paricalcitol) in Advanced, Androgen-Insensitive Prostate Cancer
Authors: Schwartz Gary G. , Hall M. Craig , Stindt Diana , Patton Suzanne , Lovato James , Torti Frank M.
Published: March 2006

Purpose: We assessed the safety and efficacy of the vitamin D analogue, 19-nor-1α-25-dihydroxyvitamin D2 (paricalcitol), in patients with androgen-independent prostate cancer.

Experimental Design: Patients received paricalcitol i.v. three times per week on an escalating dose of 5 to 25 μg (3-15 μg/m2). The primary end point was prostate-specific antigen (PSA) response. Secondary end points were characterization of toxicity in this population, changes in serum parathyroid hormone (PTH), and survival.

Results: A total of 18 patients were enrolled. No patient showed a sustained 50% drop in serum PSA, despite several large declines in PSA (e.g., 1,300 ng/mL). Paricalcitol was well tolerated. One instance of significant hypercalcemia, a serum calcium of 14.3 mg/dL, was observed at the highest dose (25 μg). At entry into the study, seven (41%) of the patients had elevated serum levels of PTH, which were significantly reduced by paricalcitol. Higher levels of serum PTH at study entry were significantly and negatively associated with survival (P < 0.01).

Conclusion: No objective responses were seen in the primary end point. However, elevated serum levels of PTH, a common feature of advanced prostate cancer, were reduced by paricalcitol. Because elevated PTH is associated with increased cardiovascular and skeletal morbidity, including an increased risk for pathologic fracture, further evaluation of paricalcitol in the reduction of skeletal morbidity in advanced prostate cancer is warranted.
Immunogenotype Changes Prevail in Relapses of Young Children with TEL-AML1-Positive Acute Lymphoblastic Leukemia and Derive Mainly from Clonal Selection
Authors: Panzer-Grümayer E. Renate , Cazzaniga Giovanni , van der Velden Vincent H.J. , del Giudice Laura , Peham Martina , Mann Georg , Eckert Conny , Schrauder Andre , Germano Giuseppe , Harbott Jochen , Basso Giuseppe , Biondi Andrea , van Dongen Jacques J.M. , Gadner Helmut , Haas Oskar A.
Published: March 2006

Purpose: Variations of the immunogenotype and TEL deletions in children with TEL-AML1+ acute lymphoblastic leukemia support the hypothesis that relapses derive from a persistent TEL-AML1+ preleukemic/leukemic clone rather than a resistant leukemia. We aimed at elucidating the relationship between the immunogenotype patterns at diagnosis and relapse as well as their clinical and biological relevance.

Patients and Methods: Immunoglobulin and T-cell receptor gene rearrangements were analyzed in 41 children with a TEL-AML1+ acute lymphoblastic leukemia and an early (up to 30 months after diagnosis; n = 12) or late (at 30 months or later; n = 29) disease recurrence by a standardized PCR approach.

Results: In 68% of the patients (group I), we identified differences in the immunogenotype patterns, whereas no changes were observed in the remaining 32% (group II). The divergence resulted more often from clonal selection than clonal evolution and consisted predominantly of losses (0-6, median 5) and/or gains (0-4, median 1) of rearrangements. The frequency and number of clonal immunoglobulin/T-cell receptor rearrangements in group I was higher at diagnosis (2-13, median 5) than at relapse (2-7, median 4), whereas it was the lowest in group II (1-5, median 3). Although group I children were younger at diagnosis, there was no correlation between particular immunogenotype patterns and remission duration.

Conclusion: These findings imply that the clonal heterogeneity in younger children most likely reflects an ongoing high recombinatorial activity in the preleukemic/leukemic cells, whereas the more uniform repertoire observed in older children mirrors end-stage rearrangement patterns of selected cell clones that evolved during the prolonged latency period.
Phase II Trial of Gefitinib 250 mg Daily in Patients with Recurrent and/or Metastatic Squamous Cell Carcinoma of the Head and Neck
Authors: Cohen Ezra E.W. , Kane Madeleine A. , List Marcy A. , Brockstein Bruce E. , Mehrotra Bhoomi , Huo Dezheng , Mauer Ann M. , Pierce Carolyn , Dekker Allison , Vokes Everett E.
Published: March 2006

Purpose: An objective response rate of 11% was reported in patients with recurrent and/or metastatic squamous cell carcinoma of the head and neck (SCCHN) treated with 500 mg daily gefitinib although the recommended dose in lung cancer is 250 mg. This study evaluated the efficacy and toxicity of 250 mg daily gefitinib in patients with recurrent and/or metastatic SCCHN.

Experimental Design: Phase II trial with objective response rate as the primary end point. Measurements of quality of life and levels of serum vascular endothelial growth factor and transforming growth factor-α were assessed before and during therapy.

Results: In 70 patients, 1 (1.4%) partial response was observed. Median progression-free survival and overall survival were 1.8 and 5.5 months, respectively. Quality of life scores improved transiently during the first weeks of therapy before returning to baseline. Median vascular endothelial growth factor and transforming growth factor-α levels were above the normal range but were not predictive of outcome. Four patients experienced grade 3 drug-related adverse events. Rash of any grade was observed in 64% of subjects. Correlation between disease control (partial response + stable disease), progression-free survival, and overall survival and grade of cutaneous toxicity was observed (P = 0.001, 0.001, and 0.008 respectively).

Conclusions: Gefitinib monotherapy at 250 mg in recurrent and/or metastatic SCCHN seems to have less activity than was previously observed for 500 mg daily. A dose-response relationship may exist for this agent in SCCHN and grade of cutaneous toxicity attributable to gefitinib is a clinical predictor of better outcome.
Predictors of Prostate Cancer Tissue Acquisition by an Undirected Core Bone Marrow Biopsy in Metastatic Castration-Resistant Prostate Cancer—A Cancer and Leukemia Group B Study
Authors: Ross Robert W. , Halabi Susan , Ou San-San , Rajeshkumar Barur R. , Woda Bruce A. , Vogelzang Nicholas J. , Small Eric J. , Taplin Mary-Ellen , Kantoff Philip W.
Published: March 2006

Purpose: Analyzing metastatic prostate cancer tissue is of considerable importance in evaluating new targeted agents, yet acquiring such tissue presents a challenge due to the predominance of bone metastases. We assessed factors predicting a successful tumor harvest from bone marrow biopsies (BMBx) in castration-resistant metastatic prostate cancer patients.

Material and Methods: Data from Cancer and Leukemia Group B study 9663 were reviewed. Bone marrow biopsies were obtained from 184 patients who underwent an office-based, unguided bone marrow biopsy of the posterior iliac crest.

Results: Forty-seven of the 184 patients (25.5%) had a positive bone marrow biopsy. When considered in a multivariate logistic regression analysis, lower hemoglobin levels, higher alkaline phosphatase, and higher lactate dehydrogenase levels were associated with a higher likelihood of a positive BMBx. The median survival time was 11 months (95% confidence interval, 8.0-14) among patients with a positive BMBx compared with 23 months (95% confidence interval, 19-27) with a negative BMBx. The median time to progression and time to prostate-specific antigen progression-free survival were also significantly decreased among positive BMBx patients. No patients with a positive BMBx survived beyond 3 years, whereas 11 of the 137 patients with a negative BMBx survived beyond 5 years.

Discussion: Using common laboratory values, a specific patient cohort can be defined from whom the yield of a nonguided BMBx would be high enough to justify this approach. For studies that require broader entry criteria, a more directed approach with image guidance is recommended.
Subcellular Localization and Protein Levels of Cyclin-Dependent Kinase Inhibitor p27 Independently Predict for Survival in Epithelial Ovarian Cancer
Authors: Psyrri Amanda , Bamias Aris , Yu Ziwei , Weinberger Paul M. , Kassar Mohamad , Markakis Sophia , Kowalski Diane , Efstathiou Eleni , Camp Robert L. , Rimm David L. , Dimopoulos Meletios A.
Published: March 2006

Purpose: p27 protein is regarded as a valuable prognostic biomarker in cancer with a potential use as a molecular target. However, different methods of immunohistochemical assessment have yielded conflicting results. Here, we sought to determine the prognostic value of p27 in ovarian cancer using a novel method of compartmentalized in situ protein analysis.

Experimental Design: A tissue array composed of 150 advanced stage ovarian cancers uniformly treated, with surgical debulking followed by platinum-paclitaxel combination chemotherapy, was constructed. For evaluation of p27 protein expression, we used an immunofluorescence-based method of automated in situ quantitative measurement of protein analysis [automated quantitative analysis (AQUA)].

Results: The mean follow-up time of the patients was 34.3 months. Patients with low Fédération Internationale des Gynaecologistes et Obstetristes stage were more likely to have low nuclear p27 expression (P = 0.008). Low nuclear p27 expression was associated with improved 3-year overall survival (66% versus 20%, P = 0.0047) and disease-free survival (27% versus 12%, P = 0.022). In multivariable analysis, adjusting for well-characterized prognostic variables, low nuclear p27 expression level was the most significant prognostic factor for both disease-free and overall survival.

Conclusions: Our results indicate that quantitative assessment of nuclear p27 expression level by automated in situ quantitative analysis is a strong predictor for outcome in ovarian cancer.
Specialized DNA Arrays for the Differentiation of Pancreatic Tumors
Authors: Buchholz Malte , Kestler Hans A. , Bauer Andrea , Böck Wolfgang , Rau Bettina , Leder Gerhard , Kratzer Wolfgang , Bommer Martin , Scarpa Aldo , Schilling Martin K. , Adler Guido , Hoheisel Jörg D. , Gress Thomas M.
Published: March 2006

Purpose: Malignant tumors of the pancreas are frequently indistinguishable from inflammatory tumors arising in the context of a chronic pancreatitis with the use of conventional imaging techniques. Thus, cytologic analysis of cells obtained by abdominal ultrasound, computed tomography, or endoscopic ultrasound–guided fine needle aspiration biopsy is required for diagnosis. However, the reliability of cytologic analyses of pancreatic fine needle aspirates remains unsatisfactory, with a diagnostic accuracy of ≤80%. The purpose of the current study was therefore to develop a novel diagnostic approach based on expression profiling of biopsy material using a specialized diagnostic cDNA array.

Experimental Design: Previous gene expression profiling studies were reevaluated to design a 558-feature diagnostic array. Minimal amounts of residual material from pancreatic cytology samples as well as surgically resected tumor and control tissue specimens were analyzed using the diagnostic array and a newly developed statistical classification system.

Results and Conclusions: Our diagnostic approach resulted in 95% accurate differentiation between ductal adenocarcinomas and nonmalignant tumors of the pancreas. The diagnostic array, in conjunction with conventional diagnostic procedures, is thus suitable to significantly improve the reliability of pancreatic cancer diagnostics and can be expected to become a valuable new tool in the routine workup of suspect masses in the pancreas.
Perturbation of the Tumor Necrosis Factor–Related Apoptosis-Inducing Ligand Cascade in Ovarian Cancer: Overexpression of FLIPL and Deregulation of the Functional Receptors DR4 and DR5
Authors: Horak Peter , Pils Dietmar , Kaider Alexandra , Pinter Alexander , Elandt Katarzyna , Sax Cornelia , Zielinski Christoph C. , Horvat Reinhard , Zeillinger Robert , Reinthaller Alexander , Krainer Michael
Published: March 2006

Purpose: Epithelial ovarian cancer is the most common cause of mortality from gynecologic malignancies. Due to advanced stage at diagnosis, most patients need systemic treatment in addition to surgery. Tumor necrosis factor (TNF)–related apoptosis-inducing ligand (TRAIL) is a member of the TNF family with a promising toxicity profile and synergistic activity with chemotherapeutic agents.

Experimental Design: We used an arrayed panel of epithelial ovarian cancer tissue to assess the protein expression of TRAIL and the clinically most relevant members of its pathway death receptors 4 and 5 (DR4 and DR5) and the long form of FLICE inhibitory protein (FLIPL).

Results: We could show that a majority (66.2%) of the tumor tissues displayed either reduced DR4/DR5 expression (20.6%), increased FLIPL expression (39.7%), or both (5.9%) as determined by immunohistochemistry. Furthermore, higher TRAIL expression in the surrounding connective tissue but not in the tumor cells is significantly (P < 0.05) linked with favorable overall survival in advanced-stage patients.

Conclusions: Mechanisms to escape the immune surveillance mediated by TRAIL are developed by ovarian cancer cells in a high percentage. TRAIL expression in the ovarian cancer microenvironment has an effect on overall survival. These findings enhance our understanding of ovarian cancer pathology and might be helpful in guiding TRAIL-based therapy in future.
The Accumulation of Specific Amplifications Characterizes Two Different Genomic Pathways of Evolution of Familial Breast Tumors
Authors: Melchor Lorenzo , Álvarez Sara , Honrado Emiliano , Palacios José , Barroso Alicia , Díez Orland , Osorio Ana , Benítez Javier
Published: March 2006

Purpose and Methods: High-level DNA amplifications are recurrently found in breast cancer, and some of them are associated with poor patient prognosis. To determine their frequency and co-occurrence in familial breast cancer, we have analyzed 80 tumors previously characterized for BRCA1 and BRCA2 germ-line mutations (26 BRCA1, 18 BRCA2, and 36 non-BRCA1/2) using high-resolution comparative genomic hybridization.

Results: Twenty-one regions were identified as recurrently amplified, such as 8q21-23 (26.25%), 17q22-25 (13.75%), 13q21-31 (12.50%), and 8q24 (11.25%), many of which were altered in each familial breast cancer group. These amplifications defined an amplifier phenotype that is correlated with a higher genomic instability. Based on these amplifications, two different genomic pathways have been established in association with 8q21-23 and/or 17q22-25 and with 13q21-31 amplification. These pathways are associated with specific genomic regions of amplification, carry specific immunohistochemical characteristics coincident with high and low aggressiveness, and have a trend to be associated with BRCA1 and BRCA2/X, respectively.

Conclusion: In summary, our data suggest the existence of two different patterns of evolution, probably common to familial and sporadic breast tumors.
Transient Improvement in Cognitive Function and Synaptic Plasticity in Rats Following Cancer Chemotherapy
Authors: Lee Garrick D. , Longo Dan L. , Wang Yue , Rifkind Joseph M. , Abdul-Raman Lilanie , Mamczarz Jacek A. , Duffy Kara B. , Spangler Edward L. , Taub Dennis D. , Mattson Mark P. , Ingram Donald K.
Published: March 2006

Background: Cancer chemotherapy has been associated with cognitive impairment. Several issues complicate such findings including the patients' health, use of multiple chemotherapeutic agents, and proper assessment of cognition. To control these factors, we conducted cognitive studies in female rats receiving cyclophosphamide or 5-fluorouracil (5FU).

Methods: Young (7 months) female Fischer-344 rats received five injections of cyclophosphamide (100 mg/kg), 5FU (150 mg/kg), or saline i.p. every 4 weeks for a total of 18 weeks. Aged (18 months) female Fischer-344 rats were treated with cyclophosphamide (80 mg/kg i.p.) for 16 weeks. After 8 to 10 weeks of recovery, rats were tested in two maze learning tasks, the Morris water maze and the Stone 14-unit T-maze. Neuronal synaptic function was assessed by examining long-term potentiation (LTP) in hippocampal slices obtained from young cyclophosphamide-treated rats.

Results: Despite the toxic effects induced by chemotherapy, cyclophosphamide- and 5FU-treated rats showed significantly better maze performance compared with controls. Following 29 to 42 weeks of recovery from chemotherapy, no significant effects were observed on maze performance. In aged rats, cyclophosphamide treatment for 14 weeks also produced toxicity, but no impairment in Stone maze learning after 16 weeks of recovery. When assessed during cyclophosphamide treatment, evidence of impaired LTP emerged; however, with 8 weeks of recovery following five cyclophosphamide treatments, we observed enhanced LTP.

Conclusion: Despite toxicity accompanying chemotherapy, no evidence of impaired cognitive performance emerged after recovery. Indeed, following 7 to 9 weeks of recovery, we noted evidence of improved learning and LTP.
Effect of Milk Thistle (Silybum marianum) on the Pharmacokinetics of Irinotecan
Authors: van Erp Nielka P.H. , Baker Sharyn D. , Zhao Ming , Rudek Michelle A. , Guchelaar Henk-Jan , Nortier Johan W.R. , Sparreboom Alex , Gelderblom Hans
Published: March 2006

Purpose: Milk thistle (Silybum marianum) is one of the most commonly used herbal therapies, and its principal constituent silybin significantly inhibits cytochrome P450 isoform 3A4 (CYP3A4) and UDP glucuronosyltransferase isoform 1A1 (UGT1A1) in vitro. Here, we investigated whether milk thistle affects the pharmacokinetics of irinotecan, a substrate for CYP3A4 and UGT1A1, in humans.

Experimental Design: Six cancer patients were treated with irinotecan (dose, 125 mg/m2) given as a 90-minute infusion once every week. Four days before the second dose, patients received 200 mg milk thistle, thrice a day, for 14 consecutive days. Pharmacokinetic studies of irinotecan and its metabolites 7-ethyl-10-hydroxycamptothecin (SN-38), 7-ethyl-10-[3,4,5-trihydroxy-pyran-2-carboxylic acid]-camptothecin (SN-38-glucuronide), and 7-ethyl-10-[4-N-(5-aminopentanoic acid)-1-piperidino]-carbonyloxycamptothecin were done during the first three irinotecan administrations.

Results: Short-term (4 days) or more prolonged intake of milk thistle (12 days) had no significant effect on irinotecan clearance (mean, 31.2 versus 25.4 versus 25.6 L/h; P = 0.16). The area under the curve ratio of SN-38 and irinotecan was slightly decreased by milk thistle (2.58% versus 2.23% versus 2.17%; P = 0.047), whereas the relative extent of glucuronidation of SN-38 was similar (10.8 versus 13.5 versus 13.1; P = 0.64). Likewise, the area under the curve ratio of 7-ethyl-10-[4-N-(5-aminopentanoic acid)-1-piperidino]-carbonyloxycamptothecin and irinotecan was unaffected by milk thistle (0.332 versus 0.285 versus 0.337; P = 0.53). The maximum plasma concentrations of silybin ranged between 0.0249 and 0.257 μmol/L.

Conclusions: Silybin concentrations after intake of milk thistle are too low to significantly affect the function of CYP3A4 and UGT1A1 in vivo, indicating that milk thistle is unlikely to alter the disposition of anticancer drugs metabolized by these enzymes.