bluuebunny/crossref_metadata_2025 huggingface dataset:
Melanoma Computer-Aided Diagnosis
Authors: Burroni Marco , Corona Rosamaria , Dell’Eva Giordana , Sera Francesco , Bono Riccardo , Puddu Pietro , Perotti Roberto , Nobile Franco , Andreassi Lucio , Rubegni Pietro
Published: September 2005

Background: Differential diagnosis of melanoma from melanocytic nevi is often not straightforward. Thus, a growing interest has developed in the last decade in the automated analysis of digitized images obtained by epiluminescence microscopy techniques to assist clinicians in differentiating early melanoma from benign skin lesions.

Purpose: The aim of this study was to evaluate diagnostic accuracy provided by different statistical classifiers on a large set of pigmented skin lesions grabbed by four digital analyzers located in two different dermatological units.

Experimental Design: Images of 391melanomas and 449 melanocytic nevi were included in the study. A linear classifier was built by using the method of receiver operating characteristic curves to identify a threshold value for a fixed sensitivity of 95%. A K-nearest-neighbor classifier, a nonparametric method of pattern recognition, was constructed using all available image features and trained for a sensitivity of 98% on a large exemplar set of lesions.

Results: On independent test sets of lesions, the linear classifier and the K-nearest-neighbor classifier produced a mean sensitivity of 95% and 98% and a mean specificity of 78% and of 79%, respectively.

Conclusions: In conclusion, our study suggests that computer-aided differentiation of melanoma from benign pigmented lesions obtained with DB-Mips is feasible and, above all, reliable. In fact, the same instrumentations used in different units provided similar diagnostic accuracy. Whether this would improve early diagnosis of melanoma and/or reducing unnecessary surgery needs to be demonstrated by a randomized clinical trial.
Antiangiogenic Therapy by Local Intracerebral Microinfusion Improves Treatment Efficiency and Survival in an Orthotopic Human Glioblastoma Model
Authors: Schmidt Nils Ole , Ziu Mateo , Carrabba Giorgio , Giussani Carlo , Bello Lorenzo , Sun Yanping , Schmidt Karl , Albert Mitchel , Black Peter Mcl. , Carroll Rona S.
Published: September 2005

Targeting active angiogenesis, which is a major hallmark of malignant gliomas, is a potential therapeutic approach. For effective inhibition of tumor-induced neovascularization, antiangiogenic compounds have to be delivered in sufficient quantities over a sustained period of time. The short biological half-life of many antiangiogenic inhibitors and the impaired intratumoral blood flow create logistical difficulties that make it necessary to optimize drug delivery for the treatment of malignant gliomas. In this study, we compared the effects of endostatin delivered by daily systemic administration or local intracerebral microinfusion on established intracranial U87 human glioblastoma xenografts in nude mice. Noninvasive magnetic resonance imaging methods were used to assess treatment effects and additional histopathological analysis of tumor volume, microvessel density, proliferation, and apoptosis rate were performed. Three weeks of local intracerebral microinfusion of endostatin (2 mg/kg/day) led to 74% (P < 0.05) reduction of tumor volumes with decreased microvessel densities (33.5%, P < 0.005) and a 3-fold increased tumor cell apoptosis (P < 0.002). Systemic administration of a 10-fold higher amount of endostatin (20 mg/kg/day) did not result in a reduction of tumor volume nor in an increase of tumor cell apoptosis despite a significant decrease of microvessel densities (26.9%, P < 0.005). Magnetic resonance imaging was used to successfully demonstrate treatment effects. The local microinfusion of human endostatin significantly increased survival when administered at 2 mg/kg/day and was prolonged further when the dose was increased to 12 mg/kg/day. Our results indicate that the local intracerebral microinfusion of antiangiogenic compounds is an effective way to overcome the logistical problems of inhibiting glioma-induced angiogenesis.
Genetic Pathways and New Progression Markers for Prostate Cancer Suggested by Microsatellite Allelotyping
Authors: von Knobloch Rolf , Konrad Lutz , Barth Peter J. , Brandt Heidrun , Wille Sebastian , Heidenreich Axel , Moll Roland , Hofmann Rainer
Published: September 2005

Purpose: At diagnosis, the biological behavior of prostate cancer is uncertain, making the choice of an adequate therapy option difficult. Performing microsatellite allelotyping on a large series of consecutive prostate cancers procured during radical prostatectomy at our institution, we sought to identify molecular markers associated with disease progression.

Experimental Design: A total of 156 consecutive fresh tumor samples was prospectively collected and macroscopically dissected from the whole prostatectomy specimen immediately after operation. Histologically 100 samples contained >75% tumor cells and were therefore enrolled in the microsatellite allelotyping, using a total of 24 polymorphic markers for the chromosomal regions 5p, 5q, 7q, 8p, 9p, 9q, 13q, 17p, 17q, and 18q. Fresh paired normal and tumor DNA was investigated in fluorescent microsatellite analysis with automated laser product detection.

Results: The incidence of tumor–DNA alterations [loss of heterozygosity or allelic imbalance (AI)] was highest for chromosomal regions 13q and 8p with 72 and 71%, respectively, followed by chromosomes 7q, 18q, 5q, and 17p with 57, 53, 41, and 39%, respectively. Alterations at chromosomes 8p, 9p, 13q, and 17p were significantly (P < 0.05) associated with advanced tumor stage, whereas AI at 8p and 17p was also associated with high Gleason score (P < 0.05). AI at 5q and 9p was associated with regional lymph node metastasis (P < 0.05). The combination of AI at 8p and 13q was strongly associated with advanced tumor stage (P < 0.0001).

Conclusions: With the obtained results, we are able to postulate three distinct pathways in prostate carcinogenesis, and we identified microsatellite markers of prognostic value.
Vaccination of Small Cell Lung Cancer Patients with Polysialic Acid orN-Propionylated Polysialic Acid Conjugated to Keyhole Limpet Hemocyanin
Authors: Krug Lee M. , Ragupathi Govind , Ng Kenneth K. , Hood Chandra , Jennings Harold J. , Guo Zhongwu , Kris Mark G. , Miller Vincent , Pizzo Barbara , Tyson Leslie , Baez Valerie , Livingston Philip O.
Published: September 2005

Purpose: Long chain polysialic acid (polySA) is a side chain on embryonal neural cell adhesion molecules that, in the adult, is largely restricted to small cell lung cancer (SCLC). Long chains of polySA are also expressed on group B meningococcus. In this clinical trial, we aimed to elicit an immune response against polysialic acid to target clinically inapparent residual disease in patients with SCLC who had successfully completed initial therapy.

Experimental Design: Patients were vaccinated with either 30 μg unmodified polySA or N-propionylated-polySA (NP-polySA), conjugated to keyhole limpet hemocyanin (KLH) and mixed with 100 μg of immunological adjuvant QS-21 at weeks 1, 2, 3, 4, 8, and 16.

Results: Of the 5 evaluable patients vaccinated with unmodified polySA, only 1 mounted an IgM antibody response to polySA. On the other hand, all 6 of the patients vaccinated with NP-polySA produced IgM antibodies to NP-polySA and these cross-reacted with unmodified polySA in all but 1 case. IgG antibodies to NP-polySA were observed in 5 of the patients, but these did not cross-react with polySA. The presence of IgM antibodies reactive with SCLC cell lines was confirmed in this group by flow cytometry. Complement-dependent lysis of tumor cells could not be demonstrated. However, postimmunization sera induced significant bactericidal activity against group B meningococcus when combined with rabbit complement.

Conclusions: Vaccination with NP-polySA-KLH, but not polySA-KLH, resulted in a consistent high titer antibody response. We are now conducting a de-escalation dosing study with NP-polySA-KLH to better assess the immunogenicity, toxicities, and optimal dose of this vaccine. We plan to incorporate this vaccine as a component of a polyvalent vaccine with GM2, fucosylated GM1, and Globo H to target SCLC.
Distribution and Clinical Significance of Heparan Sulfate Proteoglycans in Ovarian Cancer
Authors: Davies E. June , Blackhall Fiona H. , Shanks Jonathan H. , David Guido , McGown Alan T. , Swindell Ric , Slade Richard J. , Martin-Hirsch Pierre , Gallagher John T. , Jayson Gordon C.
Published: September 2005

Purpose: Heparan sulfate proteoglycans have been implicated in cancer cell growth, invasion, metastasis, and angiogenesis. This study was designed to compare their expression in normal ovary and ovarian tumors and then to examine their prognostic significance in ovarian cancer.

Experimental Design: The expression of syndecan-1, -2, -3, and -4, glypican-1, and perlecan was assessed by immunohistochemistry in 147 biopsies that included normal ovary and benign, borderline, and malignant ovarian tumors. Clinical data, including tumor stage, performance status, treatment, and survival, were collected. Univariate and multivariate analyses were performed to evaluate prognostic significance.

Results: The expression patterns of syndecan-1 and perlecan were altered in ovarian tumors compared with normal ovary. Syndecan-1 was not detected in normal ovary but was present in the epithelial and stromal cells of benign and borderline tumors and in ovarian adenocarcinomas. Perlecan expression was decreased in basement membranes that were disrupted by cancer cells but maintained in the basement membranes of blood vessels. Syndecan-2, -3, and -4, and glypican-1 were expressed in normal ovary and benign and malignant ovarian tumors. Stromal expression of syndecan-1 and glypican-1 were poor prognostic factors for survival in univariate analysis.

Conclusion: We report for the first time distinct patterns of expression of cell surface and extracellular matrix heparan sulfate proteoglycans in normal ovary compared with ovarian tumors. These data reinforce the role of the tumor stroma in ovarian adenocarcinoma and suggest that stromal induction of syndecan-1 contributes to the pathogenesis of this malignancy.
Pharmacokinetics of O6-benzylguanine in Pediatric Patients with Central Nervous System Tumors
Authors: Neville Kathleen , Blaney Susan , Bernstein Mark , Thompson Patrick , Adams Denise , Aleksic Alexander , Berg Stacey
Published: September 2005

Purpose: To report the results of the first pharmacokinetic study in pediatric patients of O6-benzylguanine (O6BG), which irreversibly inactivates the DNA repair protein alkylguanine-alkyltransferase, thus enhancing the cytotoxicity of nitrosoureas.

Experimental Design: As part of a Pediatric Oncology Group Phase I study, 120 mg/m2 of O6BG was administered i.v. over 1 h, before 1,3-bis(2-chloroethyl)-1-nitrosourea administration in children with recurrent or refractory brain tumors. Serial blood samples for plasma pharmacokinetic studies were obtained. Concentrations of O6BG and its active metabolite O6-benzyl-8-oxoguanine (8-oxo-O6BG) were measured by high-performance liquid chromatography. A pharmacokinetic model and additional first-order elimination rate constants for each compound were developed.

Results: O6BG concentration versus time data were evaluated for 25 patients. The peak concentration of O6BG (mean ± SD) was 11 ± 4 μm, and the peak concentration of its active metabolite, 8-oxo-O6BG, was 35 ± 10 μm. O6BG was rapidly eliminated with a half-life of 85 ± 140 min, area under the curve of 795 ± 320 μm · min and clearance of 760 ± 400 ml/min/m2. The area under the curve of 8-oxo-O6BG when extrapolated to infinity was 22,700 ± 11,800 μm · min. The clearance and terminal half-life of 8-oxo-O6BG were 30 ± 15 ml/min/m2 and 360 ± 220 min, respectively.

Conclusions: There is rapid elimination of O6BG after i.v. administration over 1 h. In contrast, the terminal half-life for the active metabolite, 8-oxo-O6BG, is 4-fold longer. The pharmacokinetic parameters for O6BG and 8-oxo-O6BG are similar to those reported previously in adults.
Evidence-Based Use of Neoadjuvant Taxane in Operable and Inoperable Breast Cancer
Authors: Estévez Laura G. , Gradishar William J.
Published: September 2005

Neoadjuvant chemotherapy (NC) is standard therapy for patients with locally advanced breast cancer and is increasingly used for early-stage operable disease. The aim of NC is a pathological complete response (pCR) in the breast and axillary lymph nodes, which is the best predictor of improved outcome and prolonged survival. The taxanes docetaxel and paclitaxel are potent agents in breast cancer management, with promising single-agent activity and acceptable tolerability in the neoadjuvant setting. In this review of the taxanes as NC for operable and inoperable breast cancer, we include all fully published Phase II-III studies enrolling ≥30 patients. Current evidence suggests that the sequential administration of taxane- and anthracycline-based therapy may be superior to concomitant administration. Indeed, until the recent Phase III Aberdeen study (n = 162), it was uncertain whether NC could prolong survival. In this study, sequential docetaxel after anthracycline-based NC significantly enhanced the clinical response rate and pathological complete response, and yielded a significant 3-year survival advantage, versus anthracycline-based NC alone. Recently, the Phase III National Surgical Adjuvant Breast and Bowel Project (NSABP) trial B27 trial (n = 2411) showed that sequential docetaxel after doxorubicin-cyclophosphamide significantly increased both clinical and pathological response rates for operable breast cancer, with the benefit evident in both estrogen receptor-positive and estrogen receptor-negative patients. This apparent superiority of a sequential anthracycline-taxane regimen is limited to docetaxel, with no similar Phase III trials of paclitaxel versus a non-taxane-based comparator having been conducted to date. In conclusion, current evidence supports the inclusion of a taxane in NC schedules for patients with large and locally advanced breast cancer.
Reconstitution of Caspase-3 Confers Low Glucose-Enhanced Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand Cytotoxicity and Akt Cleavage
Authors: Lee Yong J. , Froelich Christopher J. , Fujita Naoya , Tsuruo Takashi , Kim Jin H.
Published: September 2005

Purpose and Experimental Design: We have previously observed that glucose deprivation enhances tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptotic death as well as caspase activation (caspase-3, -9, and -8) in human prostate adenocarcinoma DU-145 cells. In this study, we used caspase-3-deficient MCF-7 breast cancer cells to examine the possible role of caspase-3 in glucose deprivation-enhanced TRAIL cytotoxicity.

Results: Combined glucose deprivation and 200 ng/ml TRAIL treatment markedly induced cytotoxicity in caspase-3 cDNA transfected cells (MCF-7/casp-3) but not in control vector transfected cells (MCF-7/vector). We also observed that the level of Akt, an antiapoptotic protein, was reduced by treatment with TRAIL in MCF-7/casp-3 cells but not in MCF-7/vector cells. The reduction of Akt by TRAIL was promoted in the absence of glucose in MCF-7/casp-3 cells. However, pretreatment with 20 μm Z-LEHD-FMK, a caspase-9 inhibitor, protected MCF-7/casp-3 cells from the combinatorial treatment of TRAIL and glucose deprivation-induced cytotoxicity. This compound also prevented the reduction of Akt level during the combinatorial treatment. Moreover, this Akt reduction was not inhibited by treatment with MG-132, a proteosome inhibitor. Data from site-directed mutagenesis show that Akt was cleaved at amino acid 108, but not 119, during treatment with TRAIL and glucose deprivation.

Conclusions: Our results suggest that caspase-3 is involved in the reduction of Akt level, and its involvement is mediated through caspase-9 activation. The reduction of Akt level is also due to cleavage of Akt rather than degradation of Akt.
Breast Cancer Patients with Progesterone Receptor PR-A-Rich Tumors Have Poorer Disease-Free Survival Rates
Authors: Hopp Torsten A. , Weiss Heidi L. , Hilsenbeck Susan G. , Cui Yukun , Allred D. Craig , Horwitz Kathryn B. , Fuqua Suzanne A. W.
Published: September 2005

Purpose: No study has yet analyzed whether changes in relative expression levels of progesterone receptor (PR) isoforms A and B in human breast tumors have significance in predicting clinical outcome. Human PRs are ligand-activated nuclear transcription factors that mediate progesterone action. Their presence in breast tumors is used to predict functional estrogen receptors (ERs) and, therefore, also to predict the likelihood of response to endocrine therapies and disease prognosis. The two PR isoforms, PR-A and PR-B, possess different in vitro and in vivo activities, suggesting that in tumors, the ratio of their expression may control hormone responsiveness. In general, PR-B are strong transcriptional activators, whereas PR-A can act as dominant repressors of PR-B and ER. Thus their balance may affect tamoxifen response in breast cancers.

Experimental Design: To determine whether differential expression of the PR isoforms is associated with clinical outcome and hormonal responsiveness, PR-A and PR-B were measured by immunoblot analysis of cell lysates from 297 axillary node-positive breast tumors.

Results: Expression of the two isoforms correlated with each other, as well as with ER. Additional analyses revealed that patients with PR-positive tumors but high PR-A:PR-B ratios, which were often caused by high PR-A levels, were 2.76 times more likely to relapse than patients with lower ratios, indicating resistance to tamoxifen.

Conclusions: This study suggests that knowledge of the PR-A:PR-B ratio may identify a subgroup of ER-positive/PR-positive patients with node-positive breast cancer that benefit poorly from endocrine therapy.
Loss of RhoB Expression in Human Lung Cancer Progression
Authors: Mazieres Julien , Antonia Teresita , Daste Ghislaine , Muro-Cacho Carlos , Berchery Delphine , Tillement Vanessa , Pradines Anne , Sebti Said , Favre Gilles
Published: September 2005

Purpose: RhoB is a low molecular weight GTPase belonging to the Ras protein superfamily. Whereas most Rho proteins have been shown to have a positive role in proliferation and malignant transformation, the specific role of RhoB appears more divergent. We reported previously that RhoB inhibits cell proliferation in various human cancer cells. Here, we studied the specific role played by RhoB in human lung cancer.

Experimental Design: We analyzed the expression of RhoB protein by immunostaining in human lung tissues ranging from normal to invasive carcinoma from different histological types in two large independent studies of, respectively, 94 and 45 samples. We then studied the cellular effect of RhoB overexpression in a model of lung cancer (A549, adenocarcinoma) and tumorigenicity in nude mice.

Results: We showed in both studies that RhoB protein was expressed in normal lung and decreased dramatically through lung cancer progression (P < 0.01). Interestingly, RhoB expression was lost in 96% of invasive tumors and reduced by 86% in poorly differentiated tumors compared with the nonneoplastic epithelium. Moreover, the loss of expression of RhoB correlated significantly with tumor stage and proliferative index, whereas no correlation was found between RhoB and p53 or Bcl-2 expression. We then showed that ectopic expression of RhoB in lung cancer cell line A549 suppressed cell proliferation, anchorage-independent growth, and xenograft tumor growth in nude mice.

Conclusions: RhoB loss of expression occurs very frequently in lung carcinogenesis, reinforcing its putative tumor suppressive activity, and raising the value of its potential use in cancer therapy.
The Role of α-Folate Receptor-Mediated Transport in the Antitumor Activity of Antifolate Drugs
Authors: Theti Davinder S. , Jackman Ann L.
Published: September 2005

Purpose: Raltitrexed, pemetrexed, lometrexol, and ZD9331 are antifolate drugs transported into cells via the ubiquitously expressed reduced-folate carrier. They display also high affinity for the α-folate receptor (α-FR), a low capacity folate transporter that is highly overexpressed in some epithelial tumors. The role of α-FR in the activity of the antifolates has been evaluated in two α-FR-overexpressing cell lines grown in a physiological concentration of folate (20 nm R,S-Leucovorin).

Experimental Design and Results: A431-FBP cells (transfected with the α-FR) were 3–5-fold more sensitive to the antifolates than A431 cells. KB cells (constitutive α-FR overexpression) were less sensitive to the drugs when coexposed to 1 μm folic acid to competitively inhibit binding to the α-FR. Raltitrexed, pemetrexed, and lometrexol are polyglutamated in cells leading to drug retention, e.g., the raltitrexed 4- and 24-h IC50s in A431 cells were ∼0.6 and 0.008 μm, respectively, compared with 0.003 μm for 72-h continuous exposure. A431-FBP cells were ∼3-fold more sensitive to raltitrexed and pemetrexed at all exposure times. ZD9331 is not polyglutamated, and the 4- and 24-h IC50s in A431 cells were >100 and ∼100 μm, respectively, reducing to 2 and 0.1 μm, respectively, in A431-FBP cells. The ZD9331 4- and 24-h IC50s in KB cells were 20 and 1 μm, respectively, and reversible by coaddition of 1 μm folic acid. An in situ thymidylate synthase assay demonstrated continued thymidylate synthase inhibition after ZD9331-treated A431-FBP and KB, but not A431, cells were placed in drug-free medium for 16 h. A model is proposed in which the antifolates accumulate in the α-FR/endosomal apparatus, leading to slow release into the cytoplasm. In particular, this leads to cellular retention of the nonpolyglutamatable ZD9331.

Conclusions: Antifolate drugs, particularly ZD9331, have the potential for increased efficacy in tumors that highly overexpress the α-FR.
NADPH Alkenal/One Oxidoreductase Activity Determines Sensitivity of Cancer Cells to the Chemotherapeutic Alkylating Agent Irofulven
Authors: Dick Ryan A. , Yu Xiang , Kensler Thomas W.
Published: September 2005

Illudins S and M are extremely cytotoxic products of the fungus Omphalotus illudens. They were evaluated as possible anticancer chemotherapeutic agents but displayed unfavorable therapeutic indices. Irofulven (6-hydroxymethylacylfulvene), a less toxic, synthetic derivative of illudin S, has proven very effective in many preclinical and clinical studies. It has been postulated that metabolism via hydrogenation of the 8,9-double bonds of these molecules would unmask the electrophilic, and thus, the toxic nature of their cyclopropyl moieties. Illudins S and M were found to be rapidly metabolized by NADPH-dependent alkenal/one oxidoreductase (AOR) with maximal rates of 115.9 and 44.1 μmol min−1 mg−1, and Kms of 308 and 109 μm, respectively. Irofulven was reduced at a much slower rate: Vmax 275 nmol min−1 mg−1 and Km 145 μm. Human 293 cells transfected with an AOR overexpression vector were 100-fold more sensitive than control cells to irofulven, but displayed little differential sensitivity to illudin M. Addition of glutathione to the α,β-unsaturated ketone moiety of illudin M, but not irofulven, occurred readily at physiological concentrations. Electrophilic intermediates of irofulven and illudin M that were activated by AOR were trapped with glutathione and identified by high performance liquid chromatography with tandem mass spectrometry. Samples of the 60 human tumor cell line panel used by the National Cancer Institute to evaluate potential chemotherapeutic compounds were assayed for AOR activity, which correlated positively with previously determined growth inhibitory measures for irofulven, but not illudin M or S. Collectively, these data indicate that bioactivation of irofulven by AOR plays a predominant role in its chemotherapeutic activity.
Polymorphisms of the
CYP1B1
Gene as Risk Factors for Human Renal Cell Cancer
Authors: Sasaki Masahiro , Tanaka Yuichiro , Okino Steven T. , Nomoto Mitsuharu , Yonezawa Suguru , Nakagawa Masayuki , Fujimoto Seiichiro , Sakuragi Noriaki , Dahiya Rajvir
Published: September 2005

Purpose: CYP1B1 activates various environmental carcinogens in human tissues, including renal tissues. We hypothesize that certain polymorphisms of the CYP1B1 gene are risk factors for renal cell cancer. The rationale for this hypothesis is that chemical procarcinogenic compounds require metabolic activation by oxidative enzymes such as CYP1B1 to be transformed into potentially carcinogenic forms. To test this hypothesis, we investigated the genotypic distributions of six different loci on the CYP1B1 gene and their association with renal cell cancer.

Experimental Design: DNA from 211 cases of human renal cell cancer and 200 healthy controls was analyzed by sequence-specific PCR and direct DNA sequencing to determine the genotypic frequencies of six different polymorphic loci on the CYP1B1 gene.

Results: The results of this study demonstrate that the frequencies of genotype 119T/T and genotype 432G/G were significantly higher in renal cell cancer patients compared with healthy normal controls. The relative risks were calculated as 3.01 and 2.17 for genotypes 119T/T and 432G/G, respectively, in renal cell carcinoma patients. These genotypic distributions were also significantly different between male and female patients. The relative risks of genotype 119T/T were calculated as 3.95 in males and 1.92 in females, and the relative risks of genotype 432G/G were calculated as 2.81 in males and 1.35 in females.

Conclusions: The present study demonstrates for the first time that the polymorphisms at codons 119 and 432 may be risk factors for renal cancer, especially in the male population.
Pretargeted α Emitting Radioimmunotherapy Using 213Bi 1,4,7,10-Tetraazacyclododecane-N,N′,N″,N‴-Tetraacetic Acid-Biotin
Authors: Yao Zhengsheng , Zhang Meili , Garmestani Kayhan , Axworthy Donald B. , Mallett Robert W. , Fritzberg Alan R. , Theodore Lou J. , Plascjak Paul S. , Eckelman William C. , Waldmann Thomas A. , Pastan Ira , Paik Chang H. , Brechbiel Martin W. , Carrasquillo Jorge A.
Published: September 2005

Purpose: The use of an α emitter for radioimmunotherapy has potential advantages compared with β emitters. When administered systemically optimal targeting of intact antibodies requires >24 h, therefore limiting the use of short-lived α emitters. This study investigated the biodistribution of bismuth-labeled biotin in A431 tumor-bearing mice pretargeted with antibody B3-streptavidin (B3-SA) and examined the therapeutic efficacy of the α emitter, 213Bi-labeled biotin.

Experimental Design: Biotinidase-resistant 7,10-tetraazacyclododecane-N,N′,N″,N‴-tetraacetic acid (DOTA)-biotin was radiolabeled with 205,206Bi or 213Bi. Treatment of tumor-bearing mice began by administration of B3-SA (400 μg) to target the tumor sites for 24 h. Then, an agent containing biotin and galactose groups was used to clear the conjugate from the circulation. Four h later, bismuth-radiolabeled DOTA-biotin was given, and biodistribution or therapy was evaluated. Dose escalation treatment from 3.7–74 MBq was performed, and the effects on tumors of different sizes were investigated. Tumor growth, complete blood cell counts, toxicity, and survival were monitored.

Results: Radiolabeled biotin cleared rapidly. Rapid tumor uptake resulted in much higher tumor:nontumor targeting ratios than achieved with the directly labeled monoclonal antibody. Dose escalation revealed that 74 MBq caused acute death of mice, whereas 0.37–37 MBq doses inhibited tumor growth and prolonged survival significantly. Evidence of mild hematological toxicity was noted. At therapeutically effective doses renal toxicity was observed.

Conclusions: 213Bi-DOTA-biotin, directed by the Pretarget method to tumor-targeted B3-SA, showed a therapeutic effect, although the therapeutic index was low. The source of the toxicity was most likely related to the renal toxicity.
Cyclooxygenase-2 Activation Mediates the Proangiogenic Effect of Nitric Oxide in Colorectal Cancer
Authors: Cianchi Fabio , Cortesini Camillo , Fantappiè Ornella , Messerini Luca , Sardi Iacopo , Lasagna Nadia , Perna Federico , Fabbroni Valentina , Di Felice Annamaria , Perigli Giuliano , Mazzanti Roberto , Masini Emanuela
Published: September 2005

Purpose: Up-regulation of both inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) enzymes has been reported in colorectal cancer. We aimed at evaluating the possible interaction between the nitric oxide and COX-2 pathways, and its effect on promoting tumor angiogenesis.

Experimental Design: Expression of iNOS, COX-2, vascular endothelial growth factor (VEGF), and CD31 was analyzed in tumor samples and corresponding normal mucosa obtained from 46 surgical specimens. We also evaluated iNOS activity, prostaglandin E2 (PGE2), cyclic GMP and cyclic AMP production in the same specimens. Nitrite/nitrate levels, and PGE2 and VEGF production were assessed in HCT116 and HT29 colon cancer cell lines after induction and selective inhibition of the two enzyme pathways.

Results: A significant correlation was found between iNOS and COX-2 immunohistochemical expression. PGE2 production significantly correlated with iNOS activity and cGMP levels. A significant correlation was also found among PGE2 production, microvessel density, and VEGF expression. Coinduction of both iNOS and COX-2 activities occurred after lipopolysaccharide (LPS) and epidermal growth factor (EGF) treatment in HCT116 and HT29 cells. Inhibition of iNOS by 1400W significantly reduced both LPS- and EGF-induced PGE2 production. Treatment with LPS, EGF, and arachidonic acid significantly increased VEGF production in the iNOS-negative/COX-2-positive HT29 cells. This effect was completely reversed by treatment with the selective COX-2 inhibitor celecoxib.

Conclusions: Our data showed a prominent role of nitric oxide in stimulating COX-2 activity in colorectal cancer. This interaction is likely to produce a cooperative effect in promoting angiogenesis through PGE2-mediated increase in VEGF production.
Treatment of HER-2/
neu
Overexpressing Breast Cancer Xenograft Models with Trastuzumab (Herceptin) and Gefitinib (ZD1839): Drug Combination Effects on Tumor Growth, HER-2/
neu
and Epidermal Growth Factor Receptor Expression, and Viable Hypoxic Cell Fraction
Authors: Warburton Corinna , Dragowska Wieslawa H. , Gelmon Karen , Chia Stephen , Yan Hong , Masin Dana , Denyssevych Tetyana , Wallis Anne E. , Bally Marcel B.
Published: September 2005

Purpose: The purpose of this research was to assess the effects of single agent and combination treatment with trastuzumab and gefitinib on tumor growth and tumor microenvironment in two HER-2/neu overexpressing breast xenograft models, MDA-MB-435/LCC6HER-2 (LCC6HER-2; estrogen receptor negative) and MCF-7HER-2 (estrogen receptor positive).

Experimental Design: LCC6HER-2 and MCF-7HER-2 cells, both in tissue culture and xenografts grown in SCID-Rag 2M mice, were treated with trastuzumab and gefitinib, alone or in combination. The rate of tumor growth was determined. In addition, tumor HER-2/neu and epidermal growth factor receptor expression, cell viability, cell cycle distribution, and proportion of viable hypoxic cells were determined by flow cytometric analyses of single tumor cell suspensions.

Results: Both tumor models were very sensitive to trastuzumab and moderately sensitive to gefitinib in vivo. The combination resulted in therapeutic effects, as judged by inhibition of tumor growth, which was greater (albeit not statistically significant) than that observed with trastuzumab administered as a single agent. Trastuzumab was effective in down-regulating HER-2/neu, and gefitinib mediated a reduction in epidermal growth factor receptor expression on tumor cells. In LCC6HER-2 tumors, trastuzumab significantly reduced tumor cell viability, which was not improved by the addition of gefitinib. Gefitinib dramatically reduced the proportion of viable hypoxic cells in LCC6HER-2 and MCF-7HER-2 tumors. This effect was abrogated by the addition of trastuzumab.

Conclusions: Although in vivo efficacy studies in two HER-2/neu overexpressing breast xenograft models showed that the combination of trastuzumab and gefitinib was effective, analyses of various cellular parameters failed to reveal beneficial effects and argue that this drug combination may not be favorable.
HER2 Expression in Salivary Gland Carcinomas
Authors: Glisson Bonnie , Colevas A. Dimitrios , Haddad Robert , Krane Jeoffrey , El-Naggar Adel , Kies Merrill , Costello Rosemary , Summey Carmen , Arquette Matthew , Langer Corey , Amrein Philip C. , Posner Marshall
Published: September 2005

Purpose: Previous evaluation of HER2 overexpression in salivary gland cancers indicated an incidence varying between 7 and 56%, with no clear difference among three histologically different subtypes. As part of a Phase II trial of trastuzumab for treatment of incurable salivary gland cancer, we screened 137 tumors for HER2 expression.

Experimental Design: Unstained sections of paraffin-embedded tumor samples were stained with p185/HER2 receptor antibody. Tumors with moderate (2+) to strong (3+) complete membrane staining in at least 10% of the tumor cells were scored as positive for overexpression.

Results: The overall frequency of overexpression for HER2 was 17% (23 of 137), whereas it was only 8% in the three most common histological subtypes screened. Overexpression was distinctly rare in the most common subtype screened, adenoid cystic carcinoma (4%, 3 of 70). Overexpression was very common in salivary duct cancers; 10 (83%) of 12 were positive for HER2. This observation is consistent with the typical high-grade histological features and aggressive behavior of this subtype as well as with its histogenetic similarity to breast cancer. Analysis based on histogenesis (intercalated duct versus excretory duct) indicated a higher frequency of overexpression in the latter (55%) than in the former (7%).

Conclusions: Our overall results suggest that trastuzumab will not have a major role in treatment of salivary gland cancers of intercalated duct origin. Further systematic evaluation of trastuzumab in subtypes of excretory duct origin could be supported.
N-Cadherin Is Regulated by Activin A and Associated with Tumor Aggressiveness in Esophageal Carcinoma
Authors: Yoshinaga Keiji , Inoue Hiroshi , Utsunomiya Tohru , Sonoda Hideto , Masuda Takaaki , Mimori Koshi , Tanaka Yoichi , Mori Masaki
Published: September 2005

Purpose: Activin A is a member of the transforming growth factor β superfamily and plays an important role in the differentiation of embryonic stem cells. We have reported previously that the expression of activin A is associated with lymph node metastasis in esophageal cancer, and our purpose in the current work is to clarify the molecular mechanism of the aggressive behavior of tumors that have high activin A expression.

Experimental Design: We have compared the gene expression profiles of human esophageal carcinoma cell lines that were stably transfected with activin βA, which is a subunit of activin A, with those of control human esophageal carcinoma cell lines, using a cDNA microarray.

Results: We found that the expression level of neuronal cadherin (N-cadherin) was higher in the transfectants than in the control cells. N-cadherin was located on the cell surface of the transfectants, irrespective of the expression of epithelial cadherin (E-cadherin), and the expression of N-cadherin mRNA was significantly associated with that of activin βA mRNA in clinical samples of esophageal carcinoma (n = 51; r = 0.855). A clinicopathologic analysis suggested that expression of N-cadherin mRNA was associated with the depth of tumor wall invasion, and a group of patients with high expression of N-cadherin mRNA showed a significantly poorer prognosis than a group of patients with low N-cadherin expression (P = 0.046).

Conclusions: These results indicate that activin A might mediate the expression of N-cadherin and that this may be associated with depth of invasion and poor prognosis.
A Novel Human Cancer Vaccine Elicits Cellular Responses to the Tumor-Associated Antigen, Human Chorionic Gonadotropin β
Authors: He Li-Zhen , Ramakrishna Venky , Connolly John E. , Wang Xi-Tao , Smith Patricia A. , Jones Charles L. , Valkova-Valchanova Maria , Arunakumari Alahari , Treml John F. , Goldstein Joel , Wallace Paul K. , Keler Tibor , Endres Michael J.
Published: September 2005

Purpose: The oncofetal antigen, human chorionic gonadotropin β subunit (hCGβ), is expressed by a number of carcinomas and is a prognostic indicator in renal, colorectal, bladder, and pancreatic cancers. We describe the development of a novel antibody-based dendritic cell (DC)-targeted cancer vaccine capable of eliciting cellular immune responses directed against hCGβ.

Experimental Design: The tumor-associated antigen hCGβ was coupled genetically to a human anti-DC antibody (B11). The resulting fusion protein (B11-hCGβ) was evaluated for its ability to promote tumor antigen-specific cellular immune responses in a human in vitro model. Monocyte-derived human DCs from normal donors were exposed to purified B11-hCGβ, activated with CD40 ligand, mixed with autologous lymphocytes, and tested for their ability to promote hCGβ-specific proliferative and cytotoxic T-lymphocyte responses.

Results: B11-hCGβ was found to be a soluble, well-defined, and readily purified product that specifically recognized the human mannose receptor via the B11 antibody portion of the fusion protein. B11-hCGβ functionally promoted the uptake and processing of tumor antigen by DCs, which led to the generation of tumor-specific HLA class I and class II-restricted T-cell responses, including CTLs capable of killing human cancer cell lines expressing hCGβ.

Conclusions: Although other hCG vaccines have been shown to be capable of eliciting antibody responses to hCGβ, this is the first time that cellular immune responses to hCGβ have been induced by a vaccine in a human system. This DC-targeted hCGβ vaccine holds promise for the management of a number of cancers and merits additional clinical development.
A Cox-2 Promoter-Based Replication-Selective Adenoviral Vector to Target the Cox-2-Expressing Human Bladder Cancer Cells
Authors: Shirakawa Toshiro , Hamada Katsuyuki , Zhang Zhujun , Okada Hiroshi , Tagawa Masatoshi , Kamidono Sadao , Kawabata Masato , Gotoh Akinobu
Published: September 2005

Purpose: Cyclooxygenase-2 (Cox-2), an enzyme that catalyzes the synthesis of prostaglandins, is overexpressed in a variety of premalignant and malignant conditions, including urinary bladder cancer. In the present study, we examined the feasibility of using Cox-2 promoter-based replication-selective adenovirus for targeting bladder cancer cells that express Cox-2 transcriptional activity.

Experimental Design: A series of human cancer cell lines, including three bladder cancer cell lines (KK47, T24, and 5637), were evaluated for their Cox-2 and CAR (the Coxsackievirus and adenovirus receptor) mRNA expression levels by quantitative real-time PCR. AdE3-cox2–327, a replication-selective adenovirus in which the expression of E1a is controlled by the Cox-2 promoter, was generated, and its tissue-specific activity was tested in vitro and in vivo.

Results: Three bladder cancer cell lines express higher levels of Cox-2 mRNA than does the human prostate cancer cell line PC3, the primary cultured human benign prostatic fibroblast, PF cells, and the human colon cancer cell line Colo320. Relatively higher expression of CAR mRNA was detected in the KK47, 5637, respectively, and Colo320 than in the T24, PC-3, and PF cells. In vitro assays revealed significant growth suppression of both Cox-2- and CAR-expressing bladder cancer cells KK47 and 5637 in comparison with the other cells that lack Cox-2 expression and/or CAR expression.

Conclusions: The present study demonstrated both specificity and efficacy of AdE3-cox2–327, a selectively replicated adenovirus, toward the Cox-2-expressing bladder cancer cells in vitro and in vivo. We also found that CAR expression in the target cancer cells is an important factor for the efficacy of selectively replicated adenovirus-based gene therapy.
Mutational Analysis of
BRAF
in Fine Needle Aspiration Biopsies of the Thyroid: A Potential Application for the Preoperative Assessment of Thyroid Nodules
Authors: Cohen Yoram , Rosenbaum Eli , Clark Douglas P. , Zeiger Martha A. , Umbricht Christopher B. , Tufano Ralph P. , Sidransky David , Westra William H.
Published: September 2005

Background: Fine needle aspiration (FNA) is routinely used in the preoperative evaluation of thyroid nodules, but subsequent patient management is often complicated by the inability to decisively recognize malignancy on cytologic grounds alone. Activating mutations of the BRAF oncogene commonly occur in papillary thyroid carcinomas (PTCs) but not in other types of benign and malignant thyroid lesions. Mutational analysis of FNAs could enhance selection of thyroid nodules for surgical removal.

Methods: Ninety-five excised PTCs along with 49 corresponding FNAs were evaluated for BRAF mutations by a newly developed assay that uses a novel primer extension method (MutectorR assay) and by direct sequencing. An additional 42 FNAs from thyroid nodules that were excised based on a suspicion of malignancy were also evaluated.

Results: BRAF mutations were identified in 36 of the 95 (38%) excised PTCs. By histological subtype, BRAF mutations were more common in conventional PTCs than in the follicular variant (67% versus 12%; P < 0.0001; χ2). Analysis of the preoperative FNAs accurately reflected BRAF status of the resected PTC in 46 of the 49 paired samples (94% concordance). In FNA samples grouped according to the preoperative cytologic findings (malignant, n = 25; benign, n = 11; and indeterminate, n = 55), a BRAF mutation confirmed the diagnosis of PTC in 72% of carcinomas within the malignant group, and it established the diagnosis of PTC in 16% of carcinomas within the indeterminate group. BRAF mutations were not detected in FNAs from 32 benign thyroid lesions. Direct sequencing and the MutectorR assay yielded completely concordant results.

Conclusions: BRAF mutations are common in conventional PTCs, and they are specific for PTC. A BRAF mutation can be reliably detected in cells aspirated from a thyroid nodule suggesting a role for this marker in the preoperative evaluation of thyroid nodules.
Arsenic Trioxide-Induced Death of Neuroblastoma Cells Involves Activation of Bax and Does Not Require p53
Authors: Karlsson Jenny , Øra Ingrid , Pörn-Ares Isabella , Påhlman Sven
Published: September 2005

Purpose: On the basis of clinical studies showing that arsenic trioxide (As2O3), via an apoptotic mechanism, and with minimal toxicity induces complete remission in patients with refractory acute promyelocytic leukemia and that multidrug-resistant and p53-mutated neuroblastoma cells are sensitive to As2O3 both in vitro and in vivo, we searched for molecular mechanisms involved in the As2O3-induced neuroblastoma cell death.

Experimental Design: We have studied the effect of As2O3 on the expression and cellular localization of proteins involved in drug-induced death in two neuroblastoma cell lines with intact p53 and two with mutated p53, the latter two displaying multidrug resistance.

Results: As2O3 provoked Bax expression in all tested neuroblastoma cell lines, including SK-N-BE(2) cells with mutated p53 and LA-N-1 cells, which have a deleted p53. In all cell lines exposed to As2O3, p21 Bax was proteolytically cleaved in a calpain-dependent way into the more proapoptotic p18 Bax, which was detected exclusively in a mitochondria-enriched subcellular fraction. As2O3 also caused an increase of cytoplasmic cytochrome c, translocation of antiapoptosis-inducing factor to the nuclei, and a slight activation of caspase 3. However, inhibition of caspase 3 did not prevent cell death, whereas inhibition of Bax cleavage was associated with a decreased As2O3-induced cell death.

Conclusions: We show that multidrug-resistant neuroblastoma cells die after exposure to As2O3, independent of functional p53, suggesting activation of a cytotoxic pathway different from that induced by conventional chemotherapeutic agents. We further propose that proteolytic activation of Bax is an important event in As2O3-induced cell death.
Casein Kinase II Alpha Subunit and C1-Inhibitor Are Independent Predictors of Outcome in Patients with Squamous Cell Carcinoma of the Lung
Authors: O-charoenrat Pornchai , Rusch Valerie , Talbot Simon G. , Sarkaria Inderpal , Viale Agnes , Socci Nicholas , Ngai Ivan , Rao Pulivarthi , Singh Bhuvanesh
Published: September 2005

Purpose: Gene expression profiling has been shown to be a valuable tool for prognostication and identification of cancer-associated genes in human malignancies. We aimed to identify potential prognostic marker(s) in non-small cell lung cancers using global gene expression profiles.

Experimental Design: Twenty-one previously untreated patients with non-small cell lung cancer were analyzed using the Affymetrix GeneChip high-density oligonucleotide array and comparative genomic hybridization. Identified candidate genes were validated in an independent cohort of 45 patients using quantitative real-time reverse transcription-PCR and Western blot analyses. Follow-up data for these patients was collected and used to assess outcome correlations.

Results: Hierarchical clustering analysis yielded three distinct subgroups based on gene expression profiling. Cluster I consisted of 4 patients with adenocarcinoma and 1 with squamous cell carcinoma (squamous cell carcinoma); clusters II and III consisted of 6 and 10 patients with squamous cell carcinoma, respectively. Outcome analysis was performed on the cluster groups containing solely squamous cell carcinoma, revealing significant differences in disease-specific survival rates. Moreover, patients having a combination of advanced Tumor-Node-Metastasis stage and assigned to the poor prognosis cluster group (cluster II) had significantly poorer outcomes. Comparative genomic hybridization analysis showed recurrent chromosomal losses at 1p, 3p, 17, 19, and 22 and gains/amplifications at 3q, 5p, and 8q, which did not vary significantly between the cluster groups. We internally and externally validated a subset of 11 cluster II (poor prognosis)-specific genes having corresponding chromosomal aberrations identified by comparative genomic hybridization as prognostic markers in an independent cohort of patients with lung squamous cell carcinoma identifying CSNK2A1 and C1-Inh as independent predictors of outcome.

Conclusion: CSNK2A1 and C1-Inh are independent predictors of survival in lung squamous cell carcinoma patients and may be useful as prognostic markers.