bluuebunny/crossref_metadata_2025 huggingface dataset:
Apo2l/Tumor Necrosis Factor–Related Apoptosis-Inducing Ligand Prevents Breast Cancer–Induced Bone Destruction in a Mouse Model
Authors: Thai Le Minh , Labrinidis Agatha , Hay Shelley , Liapis Vasilios , Bouralexis Steve , Welldon Katie , Coventry Brendon J. , Findlay David M. , Evdokiou Andreas
Published: May 2006

Breast cancer is the most common carcinoma that metastasizes to bone. To examine the efficacy of recombinant soluble Apo2 ligand (Apo2L)/tumor necrosis factor–related apoptosis-inducing ligand (TRAIL) against breast cancer growth in bone, we established a mouse model in which MDA-MB-231 human breast cancer cells were transplanted directly into the marrow cavity of the tibiae of athymic nude mice producing osteolytic lesions in the area of injection. All vehicle-treated control animals developed large lesions that established in the marrow cavity, eroded the cortical bone, and invaded the surrounding soft tissue, as assessed by radiography, micro-computed tomography, and histology. In contrast, animals treated with recombinant soluble Apo2L/TRAIL showed significant conservation of the tibiae, with 85% reduction in osteolysis, 90% reduction in tumor burden, and no detectable soft tissue invasion. Tumor cells explanted from Apo2L/TRAIL–treated animals were significantly more resistant to the effects of Apo2L/TRAIL when compared with the cells explanted from the vehicle-treated control animals, suggesting that prolonged treatment with Apo2/TRAIL in vivo selects for a resistant phenotype. However, such resistance was readily reversed when Apo2L/TRAIL was used in combination with clinically relevant chemotherapeutic drugs, including taxol, etoposide, doxorubicin, cisplatin, or the histone deacetylase inhibitor suberoylanilide hydroxamic acid. These studies show for the first time that Apo2L/TRAIL can prevent breast cancer–induced bone destruction and highlight the potential of this ligand for the treatment of metastatic breast cancer in bone. (Cancer Res 2006; 66(10): 5363-70)
Tumor Cell–Derived and Macrophage-Derived Cathepsin B Promotes Progression and Lung Metastasis of Mammary Cancer
Authors: Vasiljeva Olga , Papazoglou Anna , Krüger Achim , Brodoefel Harald , Korovin Matvey , Deussing Jan , Augustin Nicole , Nielsen Boye S. , Almholt Kasper , Bogyo Matthew , Peters Christoph , Reinheckel Thomas
Published: May 2006

Proteolysis in close vicinity of tumor cells is a hallmark of cancer invasion and metastasis. We show here that mouse mammary tumor virus–polyoma middle T antigen (PyMT) transgenic mice deficient for the cysteine protease cathepsin B (CTSB) exhibited a significantly delayed onset and reduced growth rate of mammary cancers compared with wild-type PyMT mice. Lung metastasis volumes were significantly reduced in PyMT;ctsb+/−, an effect that was not further enhanced in PyMT;ctsb−/− mice. Furthermore, lung colonization studies of PyMT cells with different CTSB genotypes injected into congenic wild-type mice and in vitro Matrigel invasion assays confirmed a specific role for tumor-derived CTSB in invasion and metastasis. Interestingly, cell surface labeling of cysteine cathepsins by the active site probe DCG-04 detected up-regulation of cathepsin X on PyMT;ctsb−/− cells. Treatment of cells with a neutralizing anti-cathepsin X antibody significantly reduced Matrigel invasion of PyMT;ctsb−/− cells but did not affect invasion of PyMT;ctsb+/+ or PyMT;ctsb+/− cells, indicating a compensatory function of cathepsin X in CTSB-deficient tumor cells. Finally, an adoptive transfer model, in which ctsb+/+, ctsb+/−, and ctsb−/− recipient mice were challenged with PyMT;ctsb+/+ cells, was used to address the role of stroma-derived CTSB in lung metastasis formation. Notably, ctsb−/− mice showed reduced number and volume of lung colonies, and infiltrating macrophages showed a strongly up-regulated expression of CTSB within metastatic cell populations. These results indicate that both cancer cell–derived and stroma cell–derived (i.e., macrophages) CTSB plays an important role in tumor progression and metastasis. (Cancer Res 2006; 66(10): 5242-50)
Novel 5′ Untranslated Region Variants of BCRP mRNA Are Differentially Expressed in Drug-Selected Cancer Cells and in Normal Human Tissues: Implications for Drug Resistance, Tissue-Specific Expression, and Alternative Promoter Usage
Authors: Nakanishi Takeo , Bailey-Dell Kimberly J. , Hassel Bret A. , Shiozawa Ken , Sullivan Daniel M. , Turner Joel , Ross Douglas D.
Published: May 2006

To investigate transcriptional activation of the breast cancer resistance protein gene (BCRP/ABCG2), we examined the 5′ untranslated region of BCRP mRNA in cell lines with high BCRP transcriptional activity and in normal tissues. Human choriocarcinoma cells with high endogenous BCRP expression (JAR and BeWo) and human cancer cells (MCF-7 and Igrov1) and their BCRP-overexpressing, drug-selected, multidrug-resistant derivatives (MCF-7/AdrVp, Igrov1/MX3, and Igrov1/T8) were studied. Rapid amplification of 5′-cDNA ends-PCR (5′RACE-PCR) revealed at least three novel forms of the untranslated exon 1 (E1a, E1b, and E1c) that are spliced to a common exon 2, with differential expression of these splice variants in the drug-selected cell lines. Additionally, sequence analysis of the 5′RACE-PCR products revealed multiple transcriptional start sites for each variant, particularly in the drug-selected cells. The E1c isoform predominated in drug-selected MCF-7 cell lines and was translated more efficiently in MCF-7 cells than the E1a isoform. Varying patterns of expression of the exon 1 isoforms were observed in a variety of human tissues, suggesting that tissue-specific alternative promoters of BCRP exist. In summary, we find that BCRP overexpression in the drug-selected cells is accompanied by multiple transcriptional start sites and predominance of the more efficiently translated E1c isoform. The exon 1 variation we observe suggests that alternative promoters of the BCRP gene exist. (Cancer Res 2006; 66(10): 5007-11)
Genetic Predisposition to Fiber Carcinogenesis Causes a Mesothelioma Epidemic in Turkey
Authors: Dogan A. Umran , Baris Y. Izzettin , Dogan Meral , Emri Salih , Steele Ian , Elmishad Amira G. , Carbone Michele
Published: May 2006

Malignant mesothelioma in the western world is often associated with asbestos exposure. It is a relatively rare cancer that causes ∼2,500 deaths yearly in the United States and 1,000 deaths yearly in the United Kingdom. In contrast, among people born in the Cappadocian (Turkey) villages of Tuzkoy, Karain, and “Old” Sarihidir, ∼50% of deaths are caused by malignant mesothelioma. This epidemic has been attributed to erionite exposure, a type of fibrous zeolite mineral commonly found in this area of Turkey. In these three villages, malignant mesothelioma occurs in certain houses but not in others. The hypothesis was that a unique and more carcinogenic erionite was present in certain houses and caused malignant mesothelioma. We determined the X-ray diffraction pattern and the crystal structure of erionite from malignant mesothelioma villages and compared the results with the erionite samples from nearby non–malignant mesothelioma villages and from the United States. We found the same type of erionite in Cappadocian villages, with or without a malignant mesothelioma epidemic, in households with high or no incidence of malignant mesothelioma and in the United States. Pedigree studies of the three malignant mesothelioma villages showed that malignant mesothelioma was prevalent in certain families but not in others. When high-risk malignant mesothelioma family members married into families with no history of it, malignant mesothelioma appeared in the descendants. Genetically predisposed family members born and raised outside the malignant mesothelioma villages did not seem to develop malignant mesothelioma. In summary, pedigree and mineralogical studies indicate that the malignant mesothelioma epidemic is caused by erionite exposure in genetically predisposed individuals. This is the first time that genetics is shown to influence mineral fiber carcinogenesis. (Cancer Res 2006; 66(10): 5063-68)
The c-Myc Oncogene Directly Induces the H19 Noncoding RNA by Allele-Specific Binding to Potentiate Tumorigenesis
Authors: Barsyte-Lovejoy Dalia , Lau Suzanne K. , Boutros Paul C. , Khosravi Fereshteh , Jurisica Igor , Andrulis Irene L. , Tsao Ming S. , Penn Linda Z.
Published: May 2006

The product of the MYC oncogene is widely deregulated in cancer and functions as a regulator of gene transcription. Despite an extensive profile of regulated genes, the transcriptional targets of c-Myc essential for transformation remain unclear. In this study, we show that c-Myc significantly induces the expression of the H19 noncoding RNA in diverse cell types, including breast epithelial, glioblastoma, and fibroblast cells. c-Myc binds to evolutionarily conserved E-boxes near the imprinting control region to facilitate histone acetylation and transcriptional initiation of the H19 promoter. In addition, c-Myc down-regulates the expression of insulin-like growth factor 2 (IGF2), the reciprocally imprinted gene at the H19/IGF2 locus. We show that c-Myc regulates these two genes independently and does not affect H19 imprinting. Indeed, allele-specific chromatin immunoprecipitation and expression analyses indicate that c-Myc binds and drives the expression of only the maternal H19 allele. The role of H19 in transformation is addressed using a knockdown approach and shows that down-regulation of H19 significantly decreases breast and lung cancer cell clonogenicity and anchorage-independent growth. In addition, c-Myc and H19 expression shows strong association in primary breast and lung carcinomas. This work indicates that c-Myc induction of the H19 gene product holds an important role in transformation. (Cancer Res 2006; 66(10): 5330-7)
Balance between Polyoma Enhancing Activator 3 and Activator Protein 1 Regulates Helicobacter pylori–Stimulated Matrix Metalloproteinase 1 Expression
Authors: Wu Jeng Yih , Lu Hong , Sun Yubo , Graham David Y. , Cheung Herman S. , Yamaoka Yoshio
Published: May 2006

Helicobacter pylori infection and elevated expression of tissue matrix metalloproteinase 1 (MMP-1) are both associated with gastric cancer. We investigated the regulation of MMP-1 expression during H. pylori infection. Real-time reverse transcription-PCR was used to examine mucosal MMP-1 mRNA levels in 55 patients with gastric cancers and 61 control patients. Increased MMP-1 mRNA levels in the gastric mucosa and epithelial cells were observed in H. pylori infections in which both the cag pathogenicity island (PAI) and outer inflammatory protein A (OipA) were expressed. The combined induction of c-fos, c-jun, and polyoma enhancing activator-3 (pea-3) by H. pylori caused maximal increase in MMP-1 expression. Activation of the MMP-1 promoter by H. pylori involved occupation of the activator protein 1 (AP-1) sites at −72 and −181 and, surprisingly, vacancy of the −88 PEA-3 site. Electrophoretic mobility shift, supershift, and chromatin immunoprecipitation assays showed increased binding of c-Fos and c-Jun to the −72 and −181 AP-1 sites during H. pylori infection. Importantly, during wild-type H. pylori infection, we detected increased PEA-3 binding to the −72AP-1 site and decreased PEA-3 binding to the −88 PEA-3 site. However, during infection with the cag PAI and oipA mutants, PEA-3 binding to the −88 site was detected. MMP-1 and pea-3 activities are increased in gastric cancers. Maximal activation of MMP-1 transcription requires the cag PAI and OipA, which regulate AP-1 and PEA-3 binding. Thus, cag PAI and OipA provide a possible link between bacterial virulence factors and important host factors related to disease pathogenesis. (Cancer Res 2006; 66(10): 5111-20)
Carbogen and Nicotinamide Increase Blood Flow and 5-Fluorouracil Delivery but not 5-Fluorouracil Retention in Colorectal Cancer Metastases in Patients
Authors: Gupta Nishi , Saleem Azeem , Kötz Barbara , Osman Safiye , Aboagye Eric O. , Phillips Robert , Vernon Clare , Wasan Harpreet , Jones Terry , Hoskin Peter J. , Price Patricia M.
Published: May 2006

Purpose: To examine whether carbogen and nicotinamide increases 5-fluorouracil (5-FU) delivery to colorectal cancer metastases.

Experimental Design: Six patients were scanned using positron emission tomography. Two scans were done to coincide with the start of separate chemotherapy cycles. At the second positron emission tomography session, 60 mg/kg nicotinamide was given orally 2 to 3 hours before 10-minute carbogen inhalation. In the middle of carbogen treatment, [15O]H2O (to measure regional tissue perfusion) and then [18F]5-FU (to measure 5-FU tissue pharmacokinetics) were administered.

Results: Regions of interest were drawn in 12 liver metastases, 6 spleens, 6 livers, and 12 kidneys. Nicotinamide and carbogen administration increased mean blood pO2 from 93 mm Hg (95% confidence interval, 79-198) to 278 mm Hg (95% confidence interval, 241-316; P = 0.031). Regional perfusion (mLblood/min/mLtissue) increased in metastases (mean change = 52%, range −32% to +261%, P = 0.024), but decreased in kidney (mean change = −42%, range −82% to −11%, P = 0.0005) and liver (mean change = −34%, range −43% to −26%, P = 0.031). 5-FU uptake at 3.75 minutes (m2/mL) increased in tumor (mean change = 40%, range −39% to +196%, P = 0.06) and decreased in kidney (mean change = −25%, range −71% to 12%, P = 0.043). 5-FU delivery measured as K1 increased in tumor (mean change = 74%, range −23% to +293%, P = 0.0039). No differences were seen in [18F]5-FU tumor exposure (net area under curve) and retention.

Conclusion: Nicotinamide and carbogen administration can increase 5-FU delivery to colorectal cancer liver metastases. Despite an increase in perfusion and 5-FU delivery, the effects were not directly related and did not increase 5-FU retention or tissue exposure.
RNA Interference Suppression of MUC1 Reduces the Growth Rate and Metastatic Phenotype of Human Pancreatic Cancer Cells
Authors: Tsutsumida Hideaki , Swanson Benjamin J. , Singh Pankaj K. , Caffrey Thomas C. , Kitajima Shinichi , Goto Masamichi , Yonezawa Suguru , Hollingsworth Michael A.
Published: May 2006

MUC1 is a highly glycosylated, type I transmembrane protein expressed by normal ductal epithelial cells of the pancreas, breast, lung, and gastrointestinal tract, and overexpressed in many cases of adenocarcinoma. We down-regulated MUC1 expression by RNA interference and investigated the effects on malignant and metastatic potential of a human pancreatic cancer cell line, S2-013. MUC1-suppressed clones, S2-013.MTII.C1 and S2-013.MTII.C2, were established by targeting a sequence 3,151 bp from the initiation codon and characterized in vitro for proliferation, invasion, and adhesion. We evaluated the effects of MUC1 suppression in vivo on tumor growth and metastatic properties following implantation into the cecum or pancreas of athymic mice. MUC1-suppressed clones showed significantly decreased proliferation in vitro and in vivo. Global gene expression was evaluated by oligonucleotide microarray analysis. Surprisingly, genes predicted to increase doubling times (cyclin B1 and cyclin D3) were overexpressed in MUC1-suppressed clones. There were alterations in expression of several genes that may affect the malignant properties of pancreatic cancer. Adhesion of MUC1-suppressed cells in vitro to type IV collagen and fibronectin was slightly increased, and adhesion was slightly decreased to type I collagen and laminin. Results of implantation to cecum and pancreas showed significant reduction of metastasis to lymph nodes, lung, or peritoneal sites compared with S2-013.gfp-neo control cells. These results support the hypothesis that MUC1 contributes significantly to growth and metastasis, and that down-regulation of MUC1 protein expression decreases the metastatic potential of pancreatic adenocarcinoma.
Glucocorticoids Suppress Tumor Angiogenesis and In vivo Growth of Prostate Cancer Cells
Authors: Yano Akihiro , Fujii Yasuhisa , Iwai Aki , Kageyama Yukio , Kihara Kazunori
Published: May 2006

Purpose: Glucocorticoids, such as prednisone, hydrocortisone, and dexamethasone, are known to produce some clinical benefit for patients with hormone-refractory prostate cancer (HRPC). However, the underlying mechanisms by which glucocorticoids affect HRPC growth are not well established as yet. Here, we hypothesize that the therapeutic effect of glucocorticoids on HRPC can be attributed to a direct inhibition of angiogenesis through the glucocorticoid receptor by down-regulating two major angiogenic factors, vascular endothelial growth factor (VEGF) and interleukin-8 (IL-8).

Experimental Design: The effects of dexamethasone on VEGF and IL-8 expression and cell proliferation were examined using DU145, which expresses glucocorticoid receptor. The effects of dexamethasone on DU145 xenografts were determined by analyzing VEGF and IL-8 gene expression, microvessel density, and tumor volume.

Results: Dexamethasone significantly down-regulated VEGF and IL-8 gene expression by 50% (P < 0.001) and 89% (P < 0.001), respectively, and decreased VEGF and IL-8 protein production by 55% (P < 0.001) and 74% (P < 0.001), respectively, under normoxic condition. Similarly, hydrocortisone down-regulated VEGF and IL-8 gene expression. The effects of dexamethasone were completely reversed by the glucocorticoid receptor antagonist RU486. Even under hypoxia-like conditions, dexamethasone inhibited VEGF and IL-8 expression. In DU145 xenografts, dexamethasone significantly decreased tumor volume and microvessel density and down-regulated VEGF and IL-8 gene expression, whereas dexamethasone did not affect the in vitro proliferation of the cells.

Conclusion: Glucocorticoids suppressed androgen-independent prostate cancer growth possibly due to the inhibition of tumor-associated angiogenesis by decreasing VEGF and IL-8 production directly through glucocorticoid receptor in vivo.
Phase II Clinical Trial Results Involving Treatment with Low-Dose Daily Oral Cyclophosphamide, Weekly Vinblastine, and Rofecoxib in Patients with Advanced Solid Tumors
Authors: Young Scott D. , Whissell Mark , Noble Jonathan C.S. , Cano Pablo O. , Lopez Pedro G. , Germond Colin J.
Published: May 2006

Purpose: Preclinical studies indicate that conventional chemotherapeutic agents given continuously at low doses (metronomic chemotherapy) may provide an improved therapeutic index. Cyclophosphamide and vinblastine have been best studied in experimental models, where tumor growth inhibition is achieved, at least in part, through antiangiogenic mechanisms.

Experimental Design: Fifty patients with advanced solid tumors were enrolled in this phase II trial, 43 of whom had received at least one prior chemotherapy regimen. Patients were required to have Eastern Cooperative Oncology Group performance status of ≤2, a life expectancy of >3 months, and at least one measurable lesion. All patients received oral cyclophosphamide (50 mg) and rofecoxib (25 mg) daily in addition to weekly injections of vinblastine (3 mg/m2). Half of the patients also received minocycline (100 mg) orally twice daily with the intent of further inhibiting tumor angiogenesis. The primary end point of the study was clinical benefit, defined as the percentage of patients experiencing an objective response or exhibiting stable disease for at least 6 months.

Results: For the 47 eligible patients, there were two (4%) complete responses and four (9%) partial responses, for an overall objective response rate of 13%. An additional eight patients achieved disease stabilization (stable disease ≥6 months) (17%). The primary end point of clinical benefit was therefore 30%, (95% confidence interval, 16-44%). The median progression-free survival for all patients was 103 days and 289 days for patients experiencing clinical benefit. The incidence of patients experiencing grade 3/4 toxicities were as follows: neutropenia (10/2), anemia (2/0), and thrombocytopenia (1/0). No patients developed grade 3 or 4 nausea, vomiting, mucositis, or alopecia.

Conclusions: This low-dose regimen consisting of daily oral cyclophosphamide and weekly vinblastine injections given concurrently with rofecoxib is associated with minimal toxicity and provides significant clinical benefit to patients with advanced solid tumors. These results are particularly encouraging given the nature of the study population and indicate that this approach merits further investigation in specific disease site studies.
Phase I Trial of the Trifunctional Anti-HER2 × Anti-CD3 Antibody Ertumaxomab in Metastatic Breast Cancer
Authors: Kiewe Philipp , Hasmüller Stephan , Kahlert Steffen , Heinrigs Maja , Rack Brigitte , Marmé Alexander , Korfel Agnieszka , Jäger Michael , Lindhofer Horst , Sommer Harald , Thiel Eckhard , Untch Michael
Published: May 2006

Purpose: Ertumaxomab is an intact bispecific antibody targeting HER2/neu and CD3 with selective binding to activatory Fcγ type I/III receptors, resulting in the formation of a tri-cell complex between tumor cells, T cells, and accessory cells. Patients with metastatic breast cancer were enrolled into a multicenter phase I dose-escalating trial.

Experimental Design: Three ascending doses of ertumaxomab (10-200 μg) were administered i.v. on day 1, 7 ± 1, and 13 ± 1. Safety and tolerability were the primary objectives. Secondary objectives were antitumor activity and different immunologic variables.

Results: Fifteen out of 17 enrolled patients completed the study. One hundred micrograms was identified as the maximal tolerable single dose. Most drug-related adverse events were mild and transient including fever (94%), rigors (47%), headache (35%), nausea (29%), vomiting (29%). Grades 3 and 4 (Common Toxicity Criteria) were lymphocytopenia (76%) and elevation of liver enzymes (47%). One patient (200 μg dose) developed severe hypotension and respiratory distress syndrome, another patient (150 μg dose) developed a systemic inflammatory response syndrome and acute renal failure. Aggravation of congestive heart failure was seen in one patient with preexisting ventricular dysfunction after administration of the third dose (200 μg). All adverse events were fully reversible. Antitumor response was seen in 5 out of 15 evaluable patients (one with a complete response, two with partial responses, two with stable disease) at dose levels of ≥100 μg. Measurements of cytokines (interleukin-6, interleukin-2, tumor necrosis factor-α, and IFN-γ) suggest a strong T helper cell type 1–associated immune response. The induction of human anti-mouse/anti-rat antibodies was detected in 5 out of 16 (31%) patients.

Discussion: Treatment with triple infusions of ertumaxomab yields a strong immunologic response. Doses up to 100 μg can be safely infused with close monitoring of patients. The observed clinical responses are encouraging and indicate antitumor efficacy.
Effects of Helicobacter pylori Eradication on Methylation Status of E-Cadherin Gene in Noncancerous Stomach
Authors: Leung Wai K. , Man Ellen P.S. , Yu Jun , Go Minnie Y.Y. , To Ka-fai , Yamaoka Yoshio , Cheng Victoria Y.Y. , Ng Enders K.W. , Sung Joseph J.Y.
Published: May 2006

Purpose: Promoter hypermethylation of E-cadherin plays an important role on gastric cancer development. Whereas E-cadherin methylation was frequently detected in the stomach of Helicobacter pylori–infected individuals, we tested whether eradication of H. pylori alters the methylation status of the noncancerous gastric epithelium.

Experimental Design: Endoscopic biopsies were taken from the antrum and corpus of H. pylori–infected subjects without gastric cancer. Presence of methylated E-cadherin sequences in the gastric specimens was detected by methylation-specific PCR. Bisulfite DNA sequencing was done to determine the topographical distribution and changes in methylation profiles with H. pylori eradication.

Results: Among the 28 H. pylori–infected subjects (median age, 44.5 years), 15 (53.6%) had E-cadherin methylation detected in stomach at baseline. Discordant methylation patterns between the antrum and corpus were noted in six patients. One year after successful H. pylori eradication, there was a significant reduction in the methylation density of the promoter region and exon 1 of the E-cadherin gene as detected by bisulfite DNA sequencing (P < 0.001).

Conclusion: Promoter methylation in E-cadherin was frequently detected in the stomach of H. pylori–infected individuals. Eradication of H. pylori might possibly reduce the methylation density in E-cadherin gene and the chance of subsequent neoplastic transformation.
Detection and Functional Analysis of CD8+ T Cells Specific for PRAME: a Target for T-Cell Therapy
Authors: Griffioen Marieke , Kessler Jan H. , Borghi Martina , van Soest Ronald A. , van der Minne Caroline E. , Nouta Jan , van der Burg Sjoerd H. , Medema Jan Paul , Schrier Peter I. , Falkenburg J.H. Frederik , Osanto Susanne , Melief Cornelis J.M.
Published: May 2006

Purpose: Preferentially expressed antigen on melanomas (PRAME) is an interesting antigen for T-cell therapy because it is frequently expressed in melanomas (95%) and other tumor types. Moreover, due to its role in oncogenic transformation, PRAME-negative tumor cells are not expected to easily arise and escape from T-cell immunity. The purpose of this study is to investigate the usefulness of PRAME as target for anticancer T-cell therapies.

Experimental Design: HLA-A*0201-subtyped healthy individuals and advanced melanoma patients were screened for CD8+ T cells directed against previously identified HLA-A*0201-binding PRAME peptides by IFN-γ enzyme-linked immunosorbent spot assays and tetramer staining. PRAME-specific T-cell clones were isolated and tested for recognition of melanoma and acute lymphoid leukemia (ALL) cell lines. PRAME mRNA expression was determined by quantitative real-time reverse transcription-PCR.

Results: In 30% to 40% of healthy individuals and patients, PRA100-108-specific CD8+ T cells were detected both after in vitro stimulation and directly ex vivo after isolation by magnetic microbeads. Although CD45RA− memory PRA100-108-specific T cells were found in some individuals, the majority of PRA100-108-tetramer+ T cells expressed CD45RA, suggesting a naive phenotype. PRA100-108-tetramer+ T-cell clones were shown to recognize and lyse HLA-A*0201+ and PRAME+ melanoma but not ALL cell lines. Quantitative real-time reverse transcription-PCR showed significantly lower PRAME mRNA levels in ALL than in melanoma cell lines, suggesting that PRAME expression in ALL is below the recognition threshold of our PRA100-108-tetramer+ T cells.

Conclusion: These data support the usefulness of PRAME and in particular the PRA100-108 epitope as target for T-cell therapy of PRAME-overexpressing cancers.
Fenretinide Activity in Retinoid-Resistant Oral Leukoplakia
Authors: Lippman Scott M. , Lee J. Jack , Martin Jack W. , El-Naggar Adel K. , Xu Xiaochun , Shin Dong M. , Thomas Margaret , Mao Li , Fritsche Herbert A. , Zhou Xian , Papadimitrakopoulou Vassiliki , Khuri Fadlo R. , Tran Hai , Clayman Gary L. , Hittelman Walter N. , Hong Waun Ki , Lotan Reuben
Published: May 2006

Purpose: To test the hypothesis that the retinamide N-(4-hydroxyphenyl)retinamide (fenretinide) would be clinically active potentially via receptor-independent apoptosis and receptor-dependent effects in natural retinoid-resistant oral leukoplakia patients—the first test of this hypothesis in any in vivo setting.

Experimental Design: A phase II trial of fenretinide (200 mg/d for 3 months) in oral leukoplakia patients who had not responded (de novo resistance) or who had responded and then relapsed (acquired resistance) to previous treatment with natural retinoids. We analyzed apoptosis via the terminal deoxynucleotidyl transferase–mediated nick end labeling in situ DNA fragmentation assay.

Results: We accrued 35 evaluable patients with retinoid-resistant oral leukoplakia, 12 (34.3%) had partial responses to fenretinide (95% confidence interval, 19.2-52.4%), and response was associated with acquired resistance to natural retinoids (P = 0.015, Fisher's exact test). Nine responders progressed within 9 months of stopping fenretinide. Toxicity was minimal and compliance was excellent. Mean apoptosis values (SE) increased from 0.35% (0.25%) at baseline to 1.18% (0.64%) at 3 months (P = 0.001, sign test); this increase did not correlate with clinical response. The increases in 3-month mean serum concentrations of fenretinide (0.23 μmol/L) and N-(4-methoxyphenyl)retinamide (0.57 μmol/L) correlated with decreased retinol concentrations [Spearman correlation coefficient of −0.57 (P = 0.001) and −0.43 (P = 0.01), respectively].

Conclusions: Low-dose fenretinide was clinically active and produced a small increase in apoptosis in retinoid-resistant oral leukoplakia.
Immunogenic HLA-B*0702-Restricted Epitopes Derived from Human Telomerase Reverse Transcriptase That Elicit Antitumor Cytotoxic T-Cell Responses
Authors: Adotévi Olivier , Mollier Karine , Neuveut Christine , Cardinaud Sylvain , Boulanger Emmanuelle , Mignen Blandine , Fridman Wolf-Hervé , Zanetti Maurizio , Charneau Pierre , Tartour Eric , Lemonnier François , Langlade-Demoyen Pierre
Published: May 2006

Purpose: The human telomerase reverse transcriptase (hTERT) is considered as a potential target for cancer immunotherapy because it is preferentially expressed in tumor cells. To increase the applicability of hTERT-based immunotherapy, we set out to identify CTL epitopes in hTERT restricted by HLA-B*0702 molecule, a common MHC class I allele.

Experimental Design: HLA-B*0702-restricted peptides from hTERT were selected by using a method of epitope prediction and tested for their immunogenicity in human (in vitro) and HLA-B*0702 transgenic mice (in vivo).

Results: All the six hTERT peptides that were predicted to bind to HLA-B*0702 molecule were found to induce primary human CTL responses in vitro. The peptide-specific CD8+ CTL lines were tested against various hTERT+ tumor cells. Although differences were observed according to the tumor origin, only three CTL lines specific for p277, p342, and p351 peptides exhibited cytotoxicity against tumor cells in a HLA-B*0702-restricted manner. In addition, this cytotoxicity was inhibited by the addition of peptide-loaded cold target cells and indicated that these epitopes are naturally processed and presented on the tumor cells. Further, in vivo studies using humanized HLA-B*0702 transgenic mice showed that all the candidate peptides were able to induce CTL responses after peptide immunization. Furthermore, vaccination with a plasmid DNA encoding full-length hTERT elicited peptide-specific CTL responses, indicating that these epitopes are efficiently processed in vivo.

Conclusions: Together with previously reported hTERT epitopes, the identification of new CTL epitopes presented by HLA-B*0702 increases the applicability of hTERT-based immunotherapy to treating cancer.
Evaluation of Toxicity following Electrically Mediated Interleukin-12 Gene Delivery in a B16 Mouse Melanoma Model
Authors: Heller Loree , Merkler Kathleen , Westover Jeffrey , Cruz Yolmari , Coppola Domenico , Benson Kaaron , Daud Adil , Heller Richard
Published: May 2006

Purpose: Interleukin-12 (IL-12) has potential as an immunotherapeutic agent for the treatment of cancer but is unfortunately associated with toxicity. Delivery of a plasmid encoding IL-12 with electroporation induces an antitumor effect in the B16 mouse melanoma model without serious side effects. To translate this observation to the clinic, an evaluation of toxicity was done in the mouse model.

Experimental Design: Weight change, tumor response, blood chemistry and hematology values, and serum IL-12 levels were evaluated. Multiple tissues were analyzed histopathologically.

Results: A pronounced reduction in tumor volume, including a large percentage of complete regressions, was observed after electrically mediated gene therapy. No significant increases in serum IL-12 levels were detected. Tumor-bearing mice showed an increased number of atypical hematology values when compared with normal naive controls. Statistically significant differences in chemistry and hematology values were observed sporadically in most of the standard chemistry and hematology categories in all groups. The only histopathologic abnormality specific to the animals receiving both plasmid and electroporation was inflammation associated with the kidney at the last time point.

Conclusions: In general, mice that received both plasmid and electroporation showed the least abnormal histopathologic findings and were found to be in the best health, reflecting the reduced burden of disease. No significant toxic effects due to the IL-12 gene therapy were observed.
Telomerase Template Antagonist GRN163L Disrupts Telomere Maintenance, Tumor Growth, and Metastasis of Breast Cancer
Authors: Hochreiter Amelia E. , Xiao Hongling , Goldblatt Erin M. , Gryaznov Sergei M. , Miller Kathy D. , Badve Sunil , Sledge George W. , Herbert Brittney-Shea
Published: May 2006

Purpose: Maintenance of telomeres by telomerase is critical for the continuing proliferation of most advanced cancer cells. Telomerase activity has been detected in the vast majority of cancer cells but not most normal cells, making the enzyme an attractive target for anticancer therapy. The aim of this study was to address the breast cancer translational potential of the novel telomerase inhibitor, GRN163L.

Experimental Design: In the present study, we investigated the effects of GRN163L treatment on a panel of breast cancer cells representing different tumor subtypes with varying genetic backgrounds, including ER+, ER−, HER2+, BRCA1 mutant breast tumor cells as well as doxorubicin-resistant cancer cells. To investigate the in vivo effects of GRN163L, we employed a breast cancer xenograft and metastasis model that simulates a clinical situation in which a patient arrives with a primary tumor that may be then treated or surgically removed.

Results: GRN163L effectively inhibited telomerase activity in a dose-dependent fashion in all breast cancer cell lines resulting in progressive telomere shortening. A mismatch control oligonucleotide showed no effect on telomerase activity and GRN163L did not significantly affect telomere shortening in normal human mammary epithelial cells or in endothelial cells. Breast cancer cells that exhibited telomerase inhibition also exhibited significant reduction in colony formation and tumorigenicity. Furthermore, GRN163L suppressed tumor growth and lung metastases (P = 0.017) of MDA-MB-231 cells in vivo after 4 weeks of treatment.

Conclusions: These results show in vivo effectiveness of GRN163L in breast cancer and support its promising clinical potential for breast cancer treatment.
Clinical and Immunologic Responses to Active Specific Cancer Vaccines in Human Colorectal Cancer
Authors: Nagorsen Dirk , Thiel Eckhard
Published: May 2006

Colorectal cancer is a common malignant disease, which, despite some progress, still requires improved therapeutic options. Several clinical studies have used active specific immunotherapy (i.e., vaccination) in colorectal cancer. However, the literature still lacks a comprehensive meta-analysis of this approach in advanced colorectal cancer. We did a systematic review with a meta-analysis of clinical studies to evaluate the objective clinical and immunologic response to active specific immunotherapy in patients with colorectal cancer. We conducted a search of Medline and the Web of Science, manually reviewed the literature, and consulted with experts. Criteria for including studies were colorectal cancer patients, active specific immunotherapy to induce a response directed against cancer or cancer antigens, an evaluable tumor burden (i.e., advanced or metastatic colorectal cancer), and precise classification of the patient, disease, and response. Response rates were assessed according to WHO criteria. Primary end points were the objective clinical response rate and the rate of immunologic responses. The secondary end point was the distribution of immune and clinical responses in relation to the route of vaccination and the type of vaccine. Thirty-two phase I/II studies reporting on 527 patients with advanced or metastatic colorectal cancer met all inclusion criteria. Pooled analysis showed an overall response rate (complete response + partial response) of 0.9% for advanced/metastatic colorectal cancer patients who underwent active specific immunization with a broad variety of substances (e.g., autologous tumor cells, peptide vaccine, dendritic cells, idiotypic antibody, and virus-based vaccine). Humoral immune responses were reported in 59%, and cellular ones were reported in 44% of the cases. Mixed or minor responses and disease stabilization are described in 1.9% and 8.3% of colorectal cancer patients, respectively. Pooled results of clinical trials reveal a very weak clinical response rate of <1% for active specific immunization procedures currently available for advanced colorectal cancer. Immune response induction is described in approximately half the patients.
Efficient Presentation of Naturally Processed HLA Class I Peptides by Artificial Antigen-Presenting Cells for the Generation of Effective Antitumor Responses
Authors: Hirano Naoto , Butler Marcus O. , Xia Zhinan , Berezovskaya Alla , Murray Andrew P. , Ansén Sascha , Nadler Lee M.
Published: May 2006

Appropriate presentation of tumor-associated antigens (TAA) by antigen-presenting cells (APC) is required for the development of clinically relevant antitumor T-cell responses. One common approach, which uses APC pulsed with synthetic peptides, can sometimes generate ineffective immune responses. This failure may, in part, be attributed to the formation of HLA/synthetic pulsed peptide complexes that possess different conformations compared with those of endogenously presented peptides. In addition, endogenous peptides may undergo post-translational modifications, which do not occur with synthetic peptides. Because our goal is to induce immunity that can recognize TAA that are endogenously presented by tumors, we designed an APC that would not only express the required immunoaccessory molecules but also naturally process and present target antigenic peptides. In this study, we generated an artificial APC (aAPC) that can endogenously present any chosen HLA-A*0201 (A2)–restricted peptide by processing a fusion protein that contains a unique “LTK” sequence linked to the antigenic peptide. Proteasome-dependent processing is so effective that the presented peptide can be directly eluted from the cell surface and identified by biochemical methods. Furthermore, we found that aAPC, engineered to endogenously present peptide derived from the melanoma antigen MART1, can be used to prime and expand antitumor CTL that target MART1-expressing tumor cells in a HLA-A2-restricted manner. Our engineered aAPC could serve as an “off-the-shelf” APC designed to constitutively express class I–restricted TAA peptides and could be used to generate effective T-cell responses to treat human disease.
Tumor-Targeting Properties of Novel Antibodies Specific to the Large Isoform of Tenascin-C
Authors: Brack Simon S. , Silacci Michela , Birchler Manfred , Neri Dario
Published: May 2006

Background: The targeted delivery of bioactive molecules with antibodies specific to tumor-associated antigens represents a promising strategy for improving the efficacy of tumor therapy. The large isoform of tenascin-C, an abundant glycoprotein of the tumor extracellular matrix, is strongly overexpressed in adult tissue undergoing tissue remodeling, including wound healing and neoplasia, and has been implicated in a variety of different cancers while being virtually undetectable in most normal adult tissues.

Experimental Design: We have used antibody phage technology to generate good-quality human recombinant antibodies (F16 and P12) specific to the alternatively spliced domains A1 and D of the large isoform of tenascin-C. The tumor-targeting properties of F16 and P12 were assessed by biodistribution studies in tumor xenografts using the antibodies in small immunoprotein (SIP) format.

Results: SIP(F16) selectively accumulated at the tumor site with 4.5%ID/g at 24 hours in the U87 glioblastoma model but was rapidly cleared from other organs (tumor-to-organ ratios, ∼10:1). The accumulation of SIP(P12) in the tumor was lower compared with SIP(F16) and persistent levels of radioactivity were observed in the intestine.

Conclusions: These data suggest that the F16 antibody, specific to domain A1 of tenascin-C, is a promising building block for the development of antibody-based pharmaceuticals in view of its excellent tumor-targeting performance and the strong expression of the antigen in a variety of primary and metastatic tumors.
Frequency and Spectrum of Cancers in the Peutz-Jeghers Syndrome
Authors: Hearle Nicholas , Schumacher Valérie , Menko Fred H. , Olschwang Sylviane , Boardman Lisa A. , Gille Johan J.P. , Keller Josbert J. , Westerman Anne Marie , Scott Rodney J. , Lim Wendy , Trimbath Jill D. , Giardiello Francis M. , Gruber Stephen B. , Offerhaus G. Johan A. , de Rooij Felix W.M. , Wilson J.H. Paul , Hansmann Anika , Möslein Gabriela , Royer-Pokora Brigitte , Vogel Tilman , Phillips Robin K.S. , Spigelman Allan D. , Houlston Richard S.
Published: May 2006

Background: Although an increased cancer risk in Peutz-Jeghers syndrome is established, data on the spectrum of tumors associated with the disease and the influence of germ-line STK11/LKB1 (serine/threonine kinase) mutation status are limited.

Experimental Design: We analyzed the incidence of cancer in 419 individuals with Peutz-Jeghers syndrome, and 297 had documented STK11/LKB1 mutations.

Results: Ninety-six cancers were found among individuals with Peutz-Jeghers syndrome. The risk for developing cancer at ages 20, 30, 40, 50, 60, and 70 years was 2%, 5%, 17%, 31%, 60%, and 85%, respectively. The most common cancers represented in this analysis were gastrointestinal in origin, gastroesophageal, small bowel, colorectal, and pancreatic, and the risk for these cancers at ages 30, 40, 50, and 60 years was 1%, 9%, 15%, and 33%, respectively. In women with Peutz-Jeghers syndrome, the risk of breast cancer was substantially increased, being 8% and 31% at ages 40 and 60 years, respectively. Kaplan-Meier analysis showed that cancer risks were similar in Peutz-Jeghers syndrome patients with identified STK11/LKB1 mutations and those with no detectable mutation (log-rank test of difference χ2 = 0.62; 1 df; P = 0.43). Furthermore, the type or site of STK11/LKB1 mutation did not significantly influence cancer risk.

Conclusions: The results from our study provide quantitative information on the spectrum of cancers and risks of specific cancer types associated with Peutz-Jeghers syndrome.
Long-Term Bosentan in Chronic Thromboembolic Pulmonary Hypertension
Authors: Seyfarth Hans-Jürgen , Hammerschmidt Stefan , Pankau Hans , Winkler Jörg , Wirtz Hubert
Published: May 2006

Background: There is no approved pharmacological treatment for patients with chronic thromboembolic pulmonary hypertension (CTEPH) who are not suitable for pulmonary endarterectomy (PEA). Objective: The study investigates the effect of the dual endothelin receptor antagonist bosentan on exercise tolerance (6-min walking distance, 6MWD) and right ventricular function (Tei index) in patients with CTEPH over 24 months. Methods: Twelve consecutive patients (5 males and 7 females) with CTEPH not eligible for PEA or following partial or complete failure of PEA were included in a non-randomized, open-label prospective study. All patients were WHO class III. They were included, if progressive pulmonary hypertension was diagnosed despite best supportive treatment. Bosentan was started at 62.5 mg b.i.d. and increased to the final dose of 125 mg b.i.d. Results: 6MWD and the Tei index were assessed every 6 months. We observed a significant increase in 6MWD from 319 ± 85.0 m at baseline to 391 ± 76.9 m at 6 months and a significant decrease in the Tei index from 0.39 ± 0.10 at baseline to 0.34 ± 0.08 at 6 months. This improvement was maintained over 24 months (6 MWD: 381 ± 101 m; Tei index: 0.31 ± 0.03). Six patients exhibited an improvement in WHO class at 6, 12 and 18 months, 5 demonstrated improvement at the 24-month follow-up. The remainder were stable throughout the study period. Conclusion: This is the first study demonstrating a long-term beneficial effect of bosentan on exercise tolerance (6MWD) and right heart function (Tei index) in CTEPH.
Characteristics of Multiple Primary Malignancies Associated with Lung Cancer by Gender
Authors: Haraguchi Shuji , Hioki Masafumi , Koizumi Kiyoshi , Hisayoshi Takao , Hirata Tomomi , Akiyama Hirohiko , Hirai Kyoji , Mikami Iwao , Kubokura Hirotoshi , Shimizu Kazuo
Published: May 2006

Background: There are gender differences in multiple primary malignancies associated with lung cancer (MPMLC) in terms of clinical characteristics. However, the importance of these differences in the management of patients has not been clarified. Objective: Differences in characteristics affected by gender were investigated in MPMLC to identify factors important for the proper management of the patients. Methods: Univariate and multivariate analyses were performed between 82 male and 34 female patients with MPMLC treated from August 1982 to March 2002. Results: In univariate analysis, the numbers of smokers or ex-smokers, smoking-related cancer and synchronous multiple primary malignancies were significantly increased in males with MPMLC (p < 0.0001, p < 0.05 and p < 0.05, respectively). In multivariate analysis, synchronous multiple primary malignancies and the number of smokers or ex-smokers were significantly different between male and female MPMLC. Gastric, lung and colon cancers were major constituents in male MPMLC, and 40.2% of all malignancies were smoking-related cancers. On the other hand, breast and uterine cancers were major constituents in female MPMLC, and only 20.6% of all MPMLC were smoking-related cancers. Conclusions: Male patients with MPMLC demonstrated significant smoking history and synchronous multiple primary malignancies, indicating the need for different approaches to properly manage and follow up male versus female MPMLC patients.
The Future of Bronchoscopy in Diagnosing, Staging and Treatment of Lung Cancer
Authors: Herth Felix J.F. , Eberhardt Ralf , Ernst Armin
Published: May 2006

Bronchoscopy is a central technique in diagnosing lung cancer, but also in different therapeutic approaches. A lot of techniques are available. The most common indication for bronchoscopy is for tissue sampling and determining the extent of lung cancer. Established diagnostic techniques are forceps biopsy, aspiration or brush cytology sampling, or needle aspiration. Laser therapy, electrocautery, cryotherapy and stenting are well-described techniques for the palliation of symptoms due to airway involvement in patients with advanced stages. Newer technologies, with an established role in clinical practice, are endobronchial ultrasound, autofluorescence bronchoscopy, and electromagnetic navigation. Other technologies, such as magnification, narrow-band imaging and confocal fluorescence microendoscopy, are in development for the use within the airways.