bluuebunny/crossref_metadata_2025 huggingface dataset:
Loss of
WWOX
Expression in Gastric Carcinoma
Authors: Aqeilan Rami I. , Kuroki Tamotsu , Pekarsky Yuri , Albagha Omar , Trapasso Francesco , Baffa Raffaele , Huebner Kay , Edmonds Pamela , Croce Carlo M.
Published: September 2005

Purpose: WW domain-containing oxidoreductase (WWOX) is a tumor suppressor gene that maps to the common fragile site FRA16D on chromosome 16q23.3–24.1. To investigate the role of the WWOX gene in the development of gastric carcinoma, we examined a large series of primary adenocarcinomas and nine gastric cancer cell lines for the expression of Wwox.

Experimental Design: Loss of heterozygosity, reverse-transcription-PCR, and immunohistochemistry were used to assess the role of WWOX in stomach cancer. A total of 81 primary gastric adenocarcinoma were analyzed.

Results: Loss of heterozygosity was observed in 31% of the cases and loss of Wwox protein expression was found in 65% of gastric adenocarcinoma primary specimens and 33% of gastric cancer cell lines. In addition, we found a high correlation between Wwox and Fhit protein expression.

Conclusions: Our results indicate that alterations of the WWOX gene may be involved quite frequently in gastric tumorigenesis. Our data could be used in future studies to develop diagnostic and targeted therapy of stomach cancer.
Association between Expression of Transcription Factor Sp1 and Increased Vascular Endothelial Growth Factor Expression, Advanced Stage, and Poor Survival in Patients with Resected Gastric Cancer
Authors: Yao James C. , Wang Liwei , Wei Daoyan , Gong Weida , Hassan Manal , Wu Tsung-Teh , Mansfield Paul , Ajani Jaffer , Xie Keping
Published: September 2005

The biological and clinical behaviors of cancer are affected by multiple molecular pathways that are under the control of transcription factors. Improved understanding of how transcription factors affect cancer biology may lead to improved ability to predict clinical outcome and discovery of novel therapeutic strategies. We evaluated the relationship between Sp1 and vascular endothelial growth factor (VEGF) expression, as well as their effect on survival in 86 cases of resected human gastric cancer. The degree of VEGF expression correlated highly with Sp1 expression (P < 0.01). Patients with high Sp1 expression were 98 times more likely to have high VEGF expression compared with those with negative Sp1 expression. Clinically, negative or weak Sp1 expression was associated with early stage (IA) in gastric cancer. Strong Sp1 expression was more frequently observed among patients with stage IB–IV disease (P = 0.035). Similarly, whereas strong Sp1 expression was uncommonly observed among patients with N0 or N1 disease (19 and 16%), N2/N3 gastric cancer was associated with strong Sp1 expression (48%; P = 0.034). Strong Sp1 expression was also associated with inferior survival. The median survival duration in patients who had a tumor with a negative, weak, and strong Sp1 expression was 44, 38, and 8 months (P = 0.0075), respectively, whereas patients with strong VEGF expression had a shorter survival duration; the difference was not statistically significant. When Sp1 and VEGF expression, stage, completeness of resection, histology, and patient age were entered in a Cox proportional hazards model, strong Sp1 expression (P = 0.021) and an advanced disease stage (P < 0.001) were independently prognostic of poor survival. Given the importance of Sp1 in the expression of VEGF, our data suggest that dysregulated Sp1 expression and activation play important roles in VEGF overexpression and, thus, gastric cancer development and progression.
CXCR4 and CXCL12 (SDF-1) in Prostate Cancer
Authors: Vaday Gayle G. , Hua Shao-Bing , Peehl Donna M. , Pauling Michelle H. , Lin Yu-Huei , Zhu Li , Lawrence Diana M. , Foda Hussein D. , Zucker Stanley
Published: September 2005

Purpose: Metastasis is a major cause of morbidity in prostate cancer (PCa). Several studies have shown that the chemokine receptor CXCR4 and its ligand, CXCL12 (stromal cell-derived factor-1), regulate tumor cell metastasis to specific organs. Recently, it was demonstrated that CXCL12 enhances PCa cell adhesion, migration, and invasion, implicating CXCR4 in PCa metastasis. In this study, we examined the inhibitory effects of anti-CXCR4 antibodies on CXCL12-mediated PCa cell activities.

Experimental Design: We developed fully human single chain Fv antibodies (scFv), Ab124 and Ab125, against CXCR4 using the yeast two-hybrid system. We performed immunofluorescent staining, flow cytometry, and ELISA-binding assays to measure scFv binding to PCa cells. We also examined the effects of scFv on CXCL12-mediated calcium mobilization, cell migration, and invasion.

Results: Our results confirmed that PCa cell lines express cell-surface CXCR4. Real-time quantitative reverse transcription-PCR and immunohistochemical staining also verified that CXCR4 is expressed in primary cultures of prostate epithelial cells from adenocarcinomas and in human prostate tissues. Ab124 and Ab125 demonstrated specific binding to PCa cell lines by flow cytometry and in binding assays. Preincubation with scFv resulted in significant reduction of CXCL12-induced calcium mobilization in PC-3 and LNCaP cells. Ab124 and Ab125 also inhibited PCa cell migration toward CXCL12, as well as invasion through extracellular matrix gels.

Conclusions: Ab124 and Ab125 inhibit CXCL12-mediated cellular activities by binding the receptor CXCR4. Recombinant scFv are an efficient mode of targeting tumor antigens. Considering the high incidence of PCa, the development of fully human scFv may be a useful therapeutic approach in the prevention and treatment of PCa metastasis.
A Phase I Trial of a Potent P-Glycoprotein Inhibitor, Zosuquidar Trihydrochloride (LY335979), Administered Intravenously in Combination with Doxorubicin in Patients with Advanced Malignancy
Authors: Sandler Alan , Gordon Michael , de Alwis Dinesh P. , Pouliquen Isabelle , Green Lisa , Marder Phil , Chaudhary Ajai , Fife Karen , Battiato Linda , Sweeney Christopher , Jordan Christopher , Burgess Michael , Slapak Christopher A.
Published: September 2005

Purpose: Our intention was to (a) to investigate the safety and tolerability of a potent P-glycoprotein modulator, zosuquidar trihydrochloride (LY335979), when administered i.v. alone or in combination with doxorubicin, (b) to determine the pharmacokinetics of zosuquidar and correlate exposure to inhibition of P-glycoprotein function in a surrogate assay, and (c) to compare the pharmacokinetics of doxorubicin in the presence and absence of zosuquidar.

Patients and Methods: Patients with advanced malignancies who provided written informed consent received zosuquidar and doxorubicin administered separately during the first cycle of therapy and then concurrently in subsequent cycles. Zosuquidar was given i.v. over 48 h in a cohort-dose escalation manner until the occurrence of dose-limiting toxicity or protocol specified maximum exposure. Doxorubicin doses of 45, 60, 75 mg/m2 were administered during the course of the trial.

Results: Dose escalation proceeded through 9 cohorts with a total of 40 patients. The maximal doses administered were 640 mg/m2 of zosuquidar and 75 mg/m2 of doxorubicin. No dose-limiting toxicity of zosuquidar was observed. Pharmacokinetic analysis revealed that, in the presence of zosuquidar at doses that exceeded 500 mg, there was a modest decrease in clearance (17–22%) and modest increase in area under the curve (15–25%) of doxorubicin. This change was associated with an enhanced leukopenia and thrombocytopenia but was without demonstrable clinical significance. The higher doses of zosuquidar were associated with maximal P-glycoprotein inhibition in natural killer cells.

Conclusion: Zosuquidar can be safely coadministered with doxorubicin using a 48 h i.v. dosing schedule.
The A3 Adenosine Receptor Is Highly Expressed in Tumor
versus
Normal Cells
Authors: Madi Lea , Ochaion Avivit , Rath-Wolfson Lea , Bar-Yehuda Sara , Erlanger Abigail , Ohana Gil , Harish Arie , Merimski Ofer , Barer Faina , Fishman Pnina
Published: September 2005

Purpose: A3 adenosine receptor (A3AR) activation was shown to inhibit the growth of various tumor cells via the down-regulation of nuclear factor κB and cyclin D1. To additionally elucidate whether A3AR is a specific target, a survey of its expression in tumor versus adjacent normal cells was conducted.

Experimental Design: A3AR mRNA expression in various tumor tissues was tested in paraffin-embedded slides using reverse transcription-PCR analysis. A comparison with A3AR expression in the relevant adjacent normal tissue or regional lymph node metastasis was performed. In addition, A3AR protein expression was studied in fresh tumors and was correlated with that of the adjacent normal tissue.

Results: Reverse transcription-PCR analysis of colon and breast carcinoma tissues showed higher A3AR expression in the tumor versus adjacent non-neoplastic tissue or normal tissue. Additional analysis revealed that the lymph node metastasis expressed even more A3AR mRNA than the primary tumor tissue. Protein analysis of A3AR expression in fresh tumors derived from colon (n = 40) or breast (n = 17) revealed that 61% and 78% had higher A3AR expression in the tumor versus normal adjacent tissue, respectively. The high A3AR expression level in the tumor tissues was associated with elevated nuclear factor κB and cyclin D1 levels. High A3AR mRNA expression was also demonstrated in other solid tumor types.

Conclusions: Primary and metastatic tumor tissues highly express A3AR indicating that high receptor expression is a characteristic of solid tumors. These findings and our previous data suggest A3AR as a potential target for tumor growth inhibition.
Reduced Expression of Metastasis Suppressor RhoGDI2 Is Associated with Decreased Survival for Patients with Bladder Cancer
Authors: Theodorescu Dan , Sapinoso L. M. , Conaway M. R. , Oxford G. , Hampton G. M. , Frierson H. F.
Published: September 2005

Purpose: RhoGDI2 was recently shown to be a metastasis suppressor gene in models of bladder cancer. We sought to further understand its importance in human cancer by determining the level of its expression and the distribution of its encoded protein in normal human tissues and cell lines and to evaluate whether its protein expression is a determinant of human bladder cancer progression.

Experimental Design: RhoGDI2 mRNA and protein expression was evaluated in cell lines and human tissues using Affymetrix and tissue microarrays, respectively. Tissue microarrays represented most human normal adult tissues and material from 51 patients that had undergone radical cystectomy for bladder cancer. In these 51 patients, the χ2 test was used to test for associations between RhoGDI2 and stage, grade of urothelial carcinoma, histological type, and disease-specific survival status. Cox proportional hazards regression analyses were used to estimate the effect of RhoGDI2 expression level on time to development of metastatic disease and disease-specific survival time, adjusting for grade, stage, and histological type.

Results: In normal tissues, there was strong RhoGDI2 protein expression in WBCs, endothelial cells, and transitional epithelium. RhoGDI2 mRNA expression was inversely related to the invasive and metastatic phenotype in human bladder cancer cell lines. In patients with bladder cancer, univariate analysis indicated that reduced tumor RhoGDI2 protein expression was associated with a lower actuarial 5-year disease-free and disease-specific survival (P = 0.01). In addition, patients with tumors that had low or absent RhoGDI2 had a shorter time to disease-specific death (P ≤ 0.01). When tumor grade, stage, histological type, and RhoGDI2 staining level were examined using multivariate analysis, RhoGDI2 expression was found to be an independent predictive factor for disease-specific death (P = 0.03).

Conclusions: These results suggest that RhoGDI2 is an independent predictor of prognosis for patients with bladder cancer and provide clinical evidence in support of its involvement in cancer metastasis.
The Membrane-Anchored Matrix Metalloproteinase (MMP) Regulator RECK in Combination with MMP-9 Serves as an Informative Prognostic Indicator for Colorectal Cancer
Authors: Takeuchi Taku , Hisanaga Michiyoshi , Nagao Mitsuo , Ikeda Naoya , Fujii Hisao , Koyama Fumikazu , Mukogawa Tomohide , Matsumoto Hiroshi , Kondo Shunya , Takahashi Chiaki , Noda Makoto , Nakajima Yoshiyuki
Published: September 2005

Purpose: RECK, a membrane-anchored regulator of matrix metalloproteinases (MMPs), is widely expressed in healthy tissue, whereas it is expressed at lower levels in many tumor-derived cell lines. Studies in mice and cultured cells have shown that restoration of RECK expression inhibits tumor invasion, metastasis, and angiogenesis. However, the clinical relevance of these findings remains to be fully documented. Here we examined the expression of RECK and one of its targets, MMP-9, in colorectal cancer tissue.

Experimental Design: The RECK and MMP-9 expression levels in colorectal cancer samples from 53 patients were determined by immunohistochemical techniques. The expression level of each protein was scored, and the patients were divided into two groups based on these scores. In 33 cases, we performed gelatin zymography to estimate the degree of MMP-2 and MMP-9 activation. Microvessel density and vascular endothelial growth factor (VEGF) expression were also evaluated histologically.

Results: RECK protein was detected in 30 of 53 (56.6%) specimens. Importantly, patients with tumors expressing relatively high levels of RECK (high-RECK group) had a significantly lower risk of recurrence than did patients with tumors expressing relatively low levels of RECK (low-RECK group; P = 0.011). Moreover, RECK-dominant (RECK score ≥ MMP-9 score) patients showed a significantly lower incidence of recurrence than did MMP-9-dominant patients (P = 0.0003). Multivariate analysis revealed that the RECK/MMP-9 balance was an independent prognostic factor (P = 0.0122). The expression of VEGF and microvessel density were inversely correlated with the level of RECK expression.

Conclusions: RECK/MMP-9-balance is an informative prognostic indicator for colorectal cancer. Our data also suggest that RECK suppresses tumor angiogenesis, probably by limiting the availability of VEGF in tumor tissues.
Simultaneous Expression of Furin and Vascular Endothelial Growth Factor in Human Oral Tongue Squamous Cell Carcinoma Progression
Authors: de Cicco Ricardo López , Watson James C. , Bassi Daniel E. , Litwin Samuel , Klein-Szanto Andrés J.
Published: September 2005

Purpose: Squamous cell carcinoma (SCC) of the tongue is a common malignancy of the oral cavity. Furin convertase activates several precursor matrix metalloproteinases involved in the degradation of the extracellular matrix. The pattern of expression of furin and vascular endothelial growth factor-C (VEGF-C), two key molecules in neoplasm development, was examined during the progression from normal epithelium to invasive SCC.

Experimental Design: We evaluated furin and VEGF-C expression and microvessel density (MVD) by immunohistochemistry in human tongue sections harboring normal epithelium, dysplastic epithelium, and/or SCC. Sections from 46 glossectomy specimens were assessed for furin expression. A selected group of 15 cases, each containing normal epithelium, precursor lesions, and invasive SCC, were further studied for furin and VEGF-C expression and MVD quantification. We also evaluated the pattern of furin expression and VEGF-C processing by Western blot analysis in three SCC cell lines with different degrees of aggressiveness.

Results: Furin and VEGF-C expression was notably higher in most precursor lesions and SCCs than in normal epithelia. Approximately 60% (n = 26) and 100% (n = 15) of the normal epithelia showed low-intensity staining for furin and VEGF-C, respectively. Intense staining for furin and VEGF-C was detected in ∼80% (n = 34) and 100% (n = 15) of the SCCs, respectively. A significant correlation was seen between the expression of these two markers (Spearman’s test, P < 0.00002). We found a statistically significant increase in MVD when either dysplasia (432 ± 19.06; P < 0.05) or SCC (546 ± 17.24) was compared with normal epithelium (315 ± 17.27; P < 0.0001). SCC71, the most aggressive cell line analyzed, was the one with the highest furin expression. This cell line totally processed the VEGF-C proform, whereas the less aggressive line SCC9, exhibiting the least furin expression, did not. SCC15, of intermediate aggressiveness and furin expression, showed intermediate pro-VEGF-C processing.

Conclusions: These findings suggest that furin is a useful marker of tumor progression and is responsible for VEGF-C processing. This in turn would enhance angiogenesis, leading to increased MVD associated with preinvasive and invasive neoplasia.
Simultaneously Targeting Epidermal Growth Factor Receptor Tyrosine Kinase and Cyclooxygenase-2, an Efficient Approach to Inhibition of Squamous Cell Carcinoma of the Head and Neck
Authors: Chen Zhuo (Georgia) , Zhang Xin , Li Mengfeng , Wang Zhiqiang , Wieand H. Samuel , Grandis Jennifer R. , Shin Dong M.
Published: September 2005

Purpose: Epidermal growth factor receptor (EGFR) and cyclooxygenase-2 (Cox-2) contribute to development of squamous cell carcinoma of the head and neck (SCCHN). Simultaneously blocking both EGFR and Cox-2–mediated pathways may be an efficient means of inhibiting cancer cell growth in SCCHN.

Experimental Design: A combination of EGFR-selective tyrosine kinase inhibitors (TKIs) AG1478 or ZD1839 (Iressa or gefitinib) with a Cox-2 inhibitor (Cox-2I) celecoxib (Celebrex) was studied for its effects on cell growth, cell cycle progression, and apoptosis in SCCHN cell lines by cell growth assay, clonogenic assay, flow cytometric analysis, and terminal deoxynucleotidyl transferase-mediated nick end labeling assay. A potential effect of EGFR TKIs and Cox-2I on angiogenesis was examined by endothelial capillary tube formation assay. Primary and secondary targets of EGFR TKIs and Cox-2I were also examined using immunoblotting and immunoprecipitation after the combined treatment.

Results: The combination of AG1478 or ZD1839 with celecoxib either additively or synergistically inhibited growth of the five SCCHN cell lines examined, significantly induced G1 arrest and apoptosis, and suppressed capillary formation of endothelium. Furthermore, the combination showed strong reductions of p-EGFR, p-extracellular signal-regulated kinase 1/2, and p-Akt in SCCHN cells as compared with the single agents. Both AG1478 and ZD1839 inhibited expression of Cox-2 protein, whereas celecoxib mainly blocked the production of prostaglandin E2.

Conclusions: These results suggest that cell growth inhibition induced by a combination of EGFR TKIs and Cox-2I is mediated through simultaneously blocking EGFR and Cox-2 pathways. This combination holds a great potential for the treatment and/or prevention of SCCHN.
Phase 1 Study of TLK286 (Telcyta) Administered Weekly in Advanced Malignancies
Authors: Rosen Lee S. , Laxa Bernadette , Boulos Leny , Wiggins Laura , Keck James G. , Jameson Anneliese J. , Parra Richard , Patel Kiran , Brown Gail L.
Published: September 2005

Purpose: To determine the dose-limiting toxicities, maximum tolerated dose, and pharmacokinetics of TLK286, a novel cancer prodrug, administered weekly.

Patients and Methods: Patients with advanced malignancies were treated with TLK286 administered weekly by i.v. infusion over 30 min in escalating doses 60–960 mg/m2. A treatment cycle was defined as 3 weekly treatments. Patients underwent tumor assessments on day 43, and those patients receiving clinical benefit continued on treatment until disease progression or unacceptable toxicity. Safety was assessed by the WHO criteria.

Results: Thirty-seven patients received 111 cycles of TLK286 at eight dose levels (median, 3 cycles; range, 1–16 cycles). In this study, TLK286 given weekly at 960 mg/m2 was well tolerated without dose-limiting toxicities. TLK286-related toxicities included grade 1–2 nausea and vomiting, fatigue and anemia. Nine of 31 evaluable patients continued therapy beyond day 43 and received a median of 5 cycles (range of 3–16 cycles) and experienced durable stable disease or minor tumor regression. Pharmacokinetic characteristics of TLK286 are described by an optimized two-compartment model. Mild to moderate renal or hepatic organ dysfunction did not impact the elimination of TLK286.

Conclusions: TLK286 administered weekly at doses up to 960 mg/m2 were well tolerated. The safety and antitumor activity observed in a broad range of cancer types supports Phase 2 disease-specific investigations of TLK286 given weekly at 960 mg/m2.
Treatment of Intracerebral Neoplasia and Neoplastic Meningitis with Regional Delivery of Oncolytic Recombinant Poliovirus
Authors: Ochiai Hidenobu , Moore Stephanie A. , Archer Gary E. , Okamura Tatsunori , Chewning Tracy A. , Marks Jeffrey R. , Sampson John H. , Gromeier Matthias
Published: September 2005

Purpose: Spread to the central nervous system (CNS) and the leptomeninges is a frequent complication of systemic cancers that is associated with serious morbidity and high mortality. We have evaluated a novel therapeutic approach against CNS complications of breast cancer based on the human neuropathogen poliovirus (PV).

Experimental Design: Susceptibility to PV infection and ensuing rapid cell lysis is mediated by the cellular receptor of PV, CD155. We evaluated CD155 expression in several human breast tumor tissue specimens and cultured breast cancer cell lines. In addition, we tested an oncolytic PV recombinant for efficacy in xenotransplantation models of neoplastic meningitis and cerebral metastasis secondary to breast cancer.

Results: We observed that breast cancer tissues and cell lines derived thereof express CD155 at levels mediating exquisite sensitivity toward PV-induced oncolysis in the latter. An association with the immunoglobulin superfamily molecule CD155 renders breast cancer a likely target for oncolytic PV recombinants. This assumption was confirmed in xenotransplantation models for neoplastic meningitis or solitary cerebral metastasis, where local virus treatment dramatically improved survival.

Conclusions: Our findings suggest oncolytic PV recombinants as a viable treatment option for CNS complications of breast cancer.
DNA Methylation Profiles of Lymphoid and Hematopoietic Malignancies
Authors: Takahashi Takao , Shivapurkar Narayan , Reddy Jyotsna , Shigematsu Hisayuki , Miyajima Kuniharu , Suzuki Makoto , Toyooka Shinichi , Zöchbauer-Müller Sabine , Drach Johannes , Parikh Gunjan , Zheng Yingye , Feng Ziding , Kroft Steven H. , Timmons Charles , McKenna Robert W. , Gazdar Adi F.
Published: September 2005

Purpose: Aberrant methylation of the 5′ gene promoter regions is an epigenetic phenomenon that is the major mechanism for silencing of tumor suppressor genes in many cancer types. The aims of our study were (a) to compare the methylation profiles of the major forms of hematological malignancies and (b) to determine the methylation profile of monoclonal gammopathy of undetermined significance (MGUS) and compare it with that of multiple myeloma (MM).

Experimental Design: We compared the aberrant promoter methylation profile of 14 known or suspected tumor suppressor genes in leukemias (n = 48), lymphomas (n = 42), and MMs (n = 40). We also examined the methylation profile of MGUS (n = 20), a premalignant plasma cell dyscrasia. The genes studied represent five of the six “hallmarks of cancer.”

Results: Peripheral blood lymphocytes (n = 14) from healthy volunteers were negative for methylation of all genes, and methylation percentages in 41 nonmalignant tissues (peripheral blood mononuclear cells, bone marrows, and lymph nodes) from hematological patients were low (0–9%) for all 14 genes, confirming that methylation was tumor specific. Ten of the genes were methylated at frequencies of 29–68% in one or more tumor types, and the methylation indices (an indicator of overall methylation) varied from 0.25 to 0.34. With two exceptions, the methylation patterns of leukemias and lymphomas were similar. However, the pattern of MMs varied from the other tumor types for six genes. In general, the methylation pattern of MGUS was similar to that of MM, although the methylation frequencies were lower (the methylation index of MGUS was 0.15, and that of MM was 0.3). However, the methylation frequencies of six genes were significantly higher in MGUS than in control tissues. The relatively high frequencies of methylation in MGUS are consistent with it being a premalignant condition.

Conclusions: The three major forms of lymphoid/hematopoietic malignancies show overlapping but individual patterns of methylation.
Combined Histopathological and Molecular Cytogenetic Stratification of Medulloblastoma Patients
Authors: Lamont Jayne M. , McManamy Charles S. , Pearson Andrew D. , Clifford Steven C. , Ellison David W.
Published: September 2005

This study examined the utility of stratifying children with medulloblastomas by a combination of refined histopathological classification and molecular cytogenetic evaluation.

Detailed histopathological classification of tumors from a cohort of patients (n = 87) composed mainly of children entered into the International Society of Pediatric Oncology (SIOP)/United Kingdom Children’s Cancer Study Group PNET3 trial (n = 65), included identification of the large cell/anaplastic phenotype. Fluorescence in situ hybridization was used to detect chromosome 17 abnormalities, losses of 9q22 and 10q24, and amplification of the MYCC and MYCN oncogenes.

The large cell/anaplastic phenotype, which was present in 20% of medulloblastomas, emerged as an independent prognostic indicator. Loss of 17p13.3 (38% of medulloblastomas) was found across all of the histopathological variants, whereas MYCC/MYCN amplification (6%/8% of medulloblastomas) was significantly associated with the large cell/anaplastic phenotype. Both of these genetic abnormalities emerged as prognostic indicators. Loss of 9q22 was associated with the nodular/desmoplastic medulloblastoma variant, whereas loss of 10q24 was found in all of the variants. Together with metastatic tumor at presentation, the large cell/anaplastic phenotype, 17p13.3 loss, or high-frequency MYC amplification defined a high-risk group of children whose outcome was significantly (P = 0.0002) poorer than a low-risk group without these tumor characteristics.

Combined evaluation of novel histopathological features and molecular cytogenetic abnormalities promises to allow stratification of patients with medulloblastoma, such that those likely to be cured will be spared the side effects of maximal therapy, which can be targeted at those with aggressive disease.
The Acquisition of
hMLH1
Methylation in Plasma DNA after Chemotherapy Predicts Poor Survival for Ovarian Cancer Patients
Authors: Gifford Gillian , Paul Jim , Vasey Paul A. , Kaye Stanley B. , Brown Robert ,   on behalf of the Scottish Gynaecological Clinical Trials Group
Published: September 2005

Aberrant epigenetic regulation, such as CpG island methylation and associated transcriptional silencing of genes, has been implicated in a variety of human diseases, including cancer. Methylation of genes involved in apoptosis, including the DNA mismatch repair (MMR) gene hMLH1, can occur in tumor models of resistance to chemotherapeutic drugs. However, the relevance for acquired resistance to chemotherapy of patients’ tumors remains unsubstantiated. Plasma DNA from cancer patients, including those with ovarian cancer, often contains identical DNA changes as the tumor and provides a means to monitor CpG island methylation changes. We have examined plasma DNA of patients with epithelial ovarian cancer enrolled in the SCOTROC1 Phase III clinical trial for methylation of the hMLH1 CpG island before carboplatin/taxoid chemotherapy and at relapse. Methylation of hMLH1 is increased at relapse, and 25% (34 of 138) of relapse samples have hMLH1 methylation that is not detected in matched prechemotherapy plasma samples. Furthermore, hMLH1 methylation is significantly associated with increased microsatellite instability in plasma DNA at relapse, providing an independent measure of function of the MMR pathway. Acquisition of hMLH1 methylation in plasma DNA at relapse predicts poor overall survival of patients, independent from time to progression and age (hazard ratio, 1.99; 95% confidence interval, 1.20–3.30; P = 0.007). These data support the clinical relevance of acquired hMLH1 methylation and concomitant loss of DNA MMR after chemotherapy of ovarian cancer patients. DNA methylation changes in plasma provide the potential to define patterns of methylation during therapy and identify those patient populations who would be suitable for novel epigenetic therapies.
A Phase I and Pharmacokinetic Study of VNP40101M, a Novel Sulfonylhydrazine Alkylating Agent, in Patients with Refractory Leukemia
Authors: Giles Francis , Thomas Deborah , Garcia-Manero Guillermo , Faderl Stefan , Cortes Jorge , Verstovsek Srdan , Ferrajoli Alessandra , Jeha Sima , Beran Miloslav , Koller Charles , Andreeff Michael , Cahill Ann , Clairmont Caroline , Sznol Mario , Kantarjian Hagop
Published: September 2005

Purpose: VNP40101M is a novel sulfonylhydrazine alkylating agent with broad antitumor activity in animal models. As alkylating agents are important antileukemia drugs, a Phase I and pharmacokinetic study of VNP40101M was conducted in patients with refractory or relapsed leukemias or poor-risk myelodysplastic syndromes (MDS).

Experimental Design: VNP40101M was given as a single i.v. infusion over 15–70 min on day 1. Courses were repeated every 4 weeks according to antileukemic activity. The starting dose of 220 mg/m2 was escalated by ∼33% in cohorts of 3–6 patients until a maximum-tolerated dose was established. One additional cohort was treated with the maximum-tolerated dose divided over days 1 and 8.

Results: Thirty-eight patients, including 28 with acute myeloid leukemia and 5 with MDS, received 52 courses of treatment. Nondose-limiting, reversible infusion-related toxicities were the most frequent adverse event, occurring in 24 (63%) patients on the first course. Dose escalation was terminated at 708 mg/m2 for prolonged myelosuppression in 1 of 7 patients, and 600 mg/m2 was selected as the recommended Phase II dose, with no significant extramedullary toxicity at this dose level. Two patients, 1 with MDS treated with 300 mg/m2 and 1 with acute myeloid leukemia treated with 600 mg/m2, achieved complete remission.

Conclusions: VNP40101M had significant antileukemic activity and minimal extramedullary toxicity in patients with relapsed or refractory disease.
Intravenous RNA Interference Gene Therapy Targeting the Human Epidermal Growth Factor Receptor Prolongs Survival in Intracranial Brain Cancer
Authors: Zhang Yun , Zhang Yu-feng , Bryant Joshua , Charles Andrew , Boado Ruben J. , Pardridge William M.
Published: September 2005

Purpose: The human epidermal growth factor receptor (EGFR) plays an oncogenic role in solid cancer, including brain cancer. The present study was designed to prolong survival in mice with intracranial human brain cancer with the weekly i.v. injection of nonviral gene therapy causing RNA interference (RNAi) of EGFR gene expression.

Experimental Design: Human U87 gliomas were implanted in the brain of adult scid mice, and weekly i.v. gene therapy was started at day 5 after implantation of 500,000 cells. An expression plasmid encoding a short hairpin RNA directed at nucleotides 2529–2557 within the human EGFR mRNA was encapsulated in pegylated immunoliposomes. The pegylated immunoliposome was targeted to brain cancer with 2 receptor-specific monoclonal antibodies (MAb), the murine 83–14 MAb to the human insulin receptor and the rat 8D3 MAb to the mouse transferrin receptor.

Results: In cultured glioma cells, the delivery of the RNAi expression plasmid resulted in a 95% suppression of EGFR function, based on measurement of thymidine incorporation or intracellular calcium signaling. Weekly i.v. RNAi gene therapy caused reduced tumor expression of immunoreactive EGFR and an 88% increase in survival time of mice with advanced intracranial brain cancer.

Conclusions: Weekly i.v. nonviral RNAi gene therapy directed against the human EGFR is a new therapeutic approach to silencing oncogenic genes in solid cancers. This is enabled with a nonviral gene transfer technology that delivers liposome-encapsulated plasmid DNA across cellular barriers with receptor-specific targeting ligands.
Effects of Gefitinib on Serum Epidermal Growth Factor Receptor and HER2 in Patients with Advanced Non-Small Cell Lung Cancer
Authors: Gregorc Vanesa , Ceresoli Giovanni Luca , Floriani Irene , Spreafico Anna , Bencardino Katia Bruna , Ludovini Vienna , Pistola Lorenza , Mihaylova Zhasmina , Tofanetti Francesca Romana , Ferraldeschi Massimiliano , Torri Valter , Cappuzzo Federico , Crinò Lucio , Tonato Maurizio , Villa Eugenio
Published: September 2005

Purpose: The aim of this study was to assess serum extracellular binding domains of epidermal growth factor receptor (EGFR) and HER2 as surrogate markers of Gefitinib (Iressa, ZD1839, AstraZeneca, London, United Kingdom) activity in patients with non-small cell lung cancer.

Experimental Design: Serum EGFR and HER2 levels were monitored in blood samples taken within 1 week of starting Gefitinib at day 28 and at every computed tomography scan evaluation. EGFR and HER-2 were assayed in duplicate using commercial sandwich enzyme-linked immunosorbent assay kits (Oncogene Science Bayer Corporation, Cambridge, UK). A logistic regression analysis was performed to evaluate: (1) the relationship between best overall tumor response and basal EGFR and HER2 levels, and (2) the association between best overall tumor response and the differences of EGFR and HER2 levels obtained at the best overall tumor response and at baseline.

Results: Forty-six pretreated patients were evaluated, including F/M:11/35, Eastern Cooperative Oncology Group performance status 0–1/2:39/7, IIIB/IV:11/35, and adenocarcinoma/nonadenocarcinoma 29/17. Five partial responses (11%) and 14 stable disease responses (30%) were observed. Median pretreatment EGFR and HER2 were 83.3 ng/ml and 13.7 ng/ml. For baseline EGFR and HER2, the odds ratio of progression was 0.95 [95% confidence interval (CI), 0.91–0.98; P = 0.01] and 0.87 (95% CI, 0.74–1.03; P = 0.11), respectively. The difference between the best overall tumor response and basal EGFR value was predictive for response with a 6% increase in the odds of progression for an increase of 1 ng/ml (odds ratio, 1.06; 95% CI, 1.01–1.11; P = 0.009) and for progression-free survival with a hazard ratio of 1.03 (95% CI, 1.01–1.04; P = 0.003).

Conclusion: Modifications of EGFR serum values during treatment seem to reflect Gefitinib activity.
Relationship between Non-Small Cell Lung Cancer Fluorodeoxyglucose Uptake at Positron Emission Tomography and Surgical Stage with Relevance to Patient Prognosis
Authors: Vesselle Hubert , Turcotte Eric , Wiens Linda , Schmidt Rodney , Takasugi Julie E. , Lalani Tasneem , Vallières Eric , Wood Douglas E.
Published: September 2005

Purpose: Because the tumor stage is the most significant prognostic factor for non-small cell lung cancer (NSCLC) and given that NSCLC [18F]fluorodeoxyglucose (18F-FDG) uptake appears to have prognostic significance, we examined the relationship between NSCLC 18F-FDG uptake and surgical stage.

Experimental Design: One hundred seventy-eight patients with a proven diagnosis of NSCLC were enrolled, then imaged with 18F-FDG positron emission tomography and their disease thoroughly staged. Primary tumor size at computed tomography and 18F-FDG uptake were compared to overall tumor stage and to T, N, and M stage descriptors. Tumor uptake was quantitated by maximum pixel-standardized uptake value (maxSUV) and then partial volume corrected for lesion size using recovery coefficients.

Results: A significant difference in tumor size was associated with tumors of different TNM stage, T status, N status, or M status. Similarly, the primary tumor maxSUV was significantly associated with TNM stage, T status, and M status. However, we observed no significant difference in the partial-volume-corrected tumor maxSUV for different stages; different T, N, or M descriptors; tumors without evidence of spread (N0M0) versus tumors with nodal spread (N1,2,3M0); or tumors without spread (N0M0) versus all others.

Conclusions: We found an association between tumor stage and 18F-FDG maxSUV, but this relationship disappeared after correction of tumor uptake for lesion size. Therefore, if partial-volume-corrected 18F-FDG uptake is prognostic of NSCLC outcome, it is not on the basis of a relationship with tumor stage but through a different mechanism.
Mesothelin
Authors: Hassan Raffit , Bera Tapan , Pastan Ira
Published: September 2005

Mesothelin is a differentiation antigen present on normal mesothelial cells and overexpressed in several human tumors, including mesothelioma and ovarian and pancreatic adenocarcinoma. The mesothelin gene encodes a precursor protein that is processed to yield the 40-kDa protein, mesothelin, attached to the cell membrane by a glycosylphosphatidyl inositol linkage and a 31-kDa shed fragment named megakaryocyte-potentiating factor. The biological function of mesothelin is not known. Mesothelin is a promising candidate for tumor-specific therapy, given its limited expression in normal tissues and high expression in several cancers. SS1(dsFv)PE38 is a recombinant anti-mesothelin immunotoxin that is undergoing clinical evaluation in patients with mesothelin-expressing tumors. There is evidence that mesothelin is an immunogenic protein and could be exploited as a therapeutic cancer vaccine. A soluble mesothelin variant has been identified and could be a useful tumor marker for malignant mesotheliomas.
Transcriptional Blocks Limit Adenoviral Replication in Primary Ovarian Tumor
Authors: Preuss Meredith A. , Lam John T. , Wang Minghui , Leath Charles A. , Kataram Manjula , Mahasreshti Parameshwar J. , Alvarez Ronald D. , Curiel David T.
Published: September 2005

Purpose: Despite the success of conditionally replicating adenoviruses in tumor models, clinical success has been limited when they are used as a single modality agent. Overcoming the disparity in efficacy between in vivo animal models and human use is a key hurdle for better conditionally replicating adenovirus therapy in humans. We endeavored to identify biological blocks to adenoviral infection and replication in tumor cells.

Experimental Design: We hypothesized that the differences in adenoviral replication between ovarian cancer cell lines and patient tumor samples are the result of a block in viral RNA transcription. To test this hypothesis, established ovarian cancer cell lines and purified patient ovarian cancer cells were infected with wild-type adenovirus. RNA for early adenoviral genes E1A and E1B as well as the late transcripts for fiber and hexon were measured using real-time PCR.

Results: Established ovarian cancer cell lines treated with wild-type virus had a lower E1A:E1B ratio than the patient samples. Additionally, the levels of fiber and hexon relative to E1A were also decreased in the patient samples compared with the established cell lines. These findings were consistent with an early- to late-phase block in the adenovirus replication cycle.

Conclusions: These data suggest that the biology of abortive infection in the patient samples may be linked to a defect in the production of early and late viral transcripts. Identification of factors leading to abortive infection will be crucial to understanding the low viral replication in patient samples.
Sequencing of Endocrine Therapy in Postmenopausal Women with Advanced Breast Cancer
Authors: Ingle James N.
Published: September 2005

The introduction of the nonsteroidal aromatase inhibitor (NS-AI) anastrozole as an alternative to tamoxifen for adjuvant therapy of women with resected hormone receptor-positive breast cancer has added a management category into which patients presenting with metastatic disease can be placed. There are now essentially three such categories: (a) tamoxifen sensitive (no prior AI); (b) tamoxifen resistant (no prior AI); and (c) NS-AI resistant (no prior tamoxifen). Well-conducted Phase III trials provide evidence for choosing first-line therapy for advanced disease in categories a and b. In tamoxifen-sensitive patients, one can choose either NS-AI, anastrozole, or letrozole. In tamoxifen-resistant patients, one can choose either of the NS-AIs, the steroidal AI exemestane, or the estrogen receptor down-regulator fulvestrant. The situation is quite different for patients in category c. There are no Phase III trials of agents in patients who have experienced disease progression on a NS-AI. Phase II data are available for exemestane and high-dose estrogens, and retrospective data are available for tamoxifen and fulvestrant. Additional clinical trials are needed to determine an optimal sequencing strategy.
Genomic Approaches to Understanding Mammary Tumor Progression in Transgenic Mice and Responses to Therapy
Authors: Green Jeffrey E. , Desai Kartiki , Ye Yumei , Kavanaugh Claudine , Calvo Alfonso , Huh Jung-Im
Published: September 2005

Scores of genetically engineered mice have been generated in the quest to understand mechanisms of breast cancer development and progression. More recently, there has been a growing trend for using such models for testing various therapeutic strategies and agents. The application of these mouse models for these purposes requires that they be characterized in ways that demonstrate they possess important similarities to human breast cancer. In particular, detailed comparisons of the features of the models to human breast cancer must include attention to the histological phenotypes, chromosomal and molecular alterations, and the predictive value of the models for preclinical testing. Whereas these models have become important tools for the study of breast cancer, the great majority of existing mouse mammary cancer models develop tumors that are estrogen receptor negative, with relatively few models demonstrating metastatic spread to the lungs, and none developing metastases to bone. This review focuses on recent studies using genomic approaches to further understand the oncogenic processes occurring in mouse models of mammary cancer and to compare these changes with those identified in human breast cancer. Gene expression profiling is being applied to help define pharmacological responses that occur in vivo. Detailed genomic analyses will provide important information for selecting models for specific experimental purposes, contribute to the understanding of oncogene-specific expression signatures and potential therapeutic targets, and further define mechanisms of chemoprevention and chemotherapy.
Regulatory Nodes That Integrate and Coordinate Signaling as Potential Targets for Breast Cancer Therapy
Authors: Cui Xiaojiang , Lee Adrian V.
Published: September 2005

Blockade of the estrogen receptor (ER) with antiestrogens and aromatase inhibitors is effective in the treatment of breast cancer. Why ER plays such a dominant role in breast cancer and represents such an excellent target remains to be defined. The ability of ER to respond to multiple inputs and to control expression of multiple downstream genes may be one of the reasons why ER is such a powerful target for breast cancer treatment. The recent modest performance of a number of targeted therapies in breast cancer has raised the question whether we will ever develop therapies that have such success as antiestrogens. Targeted therapies tend to inhibit a single pathway that is probably altered in only a subset of patients. Even within this subset, only a limited number of patients respond. The evidence that virtually all pathways can cross-talk and that they exhibit several layers of redundancy reveals a complexity of signaling networks that may defy the generation of targeted therapies with efficacy similar to antiestrogens. However, there are clearly regulatory nodes that can integrate multiple upstream inputs and elicit diverse downstream outputs. We provide evidence and rationales for integrins, insulin receptor substrates (IRSs), and cyclin D1 as potential therapeutic targets. These proteins, similar to ER, can integrate and coordinate multiple signals in breast cancer cells and thus mediate diverse aspects of breast cancer progression. New treatment targets will emerge in light of more global models of signal transduction that fully integrate all aspects of cell biology such as the role of the extracellular matrix and will hopefully result in the development of targeted therapies that show efficacy similar to antiestrogens.
Soluble CD40 Ligand Plasma Levels in Lung Cancer
Authors: Roselli Mario , Mineo Tommaso C. , Basili Stefania , Martini Francesca , Mariotti Sabrina , Aloe Simona , Del Monte Girolamo , Ambrogi Vincenzo , Spila Antonella , Palmirotta Raffaele , D’Alessandro Roberta , Davì Giovanni , Guadagni Fiorella , Ferroni Patrizia
Published: September 2005

Purpose: Tumor-induced platelet activation may cause the release of various cytokines, including CD40 ligand (CD40L). Activation of the CD40/CD40L pathway in human tumors may result in thrombin generation, which is known to be involved in angiogenesis. Thus, we investigated whether soluble (s)CD40L levels are increased in patients with lung cancer as a result of platelet and/or coagulation activation.

Experimental Design: Citrated plasma samples were obtained from 120 patients with different stages and histotypes of lung cancer and 60 age- and sex-matched control subjects. sCD40L, sP-selectin (marker of platelet activation), prothrombin fragment 1 + 2, and thrombin-antithrombin III complex levels (both markers of coagulative activation) were measured in all samples.

Results: Patients with lung cancer had median sCD40L levels higher than in control subjects (0.46 versus 0.13 ng/ml; P < 0.0001), although correlation with the stage of disease was not evident. Nonetheless, sCD40L levels were significantly higher in squamous cancer compared with adenocarcinoma (0.75 versus 0.27 ng/ml; P < 0.05). Moreover, median sCD40L levels were higher in stage IV compared with nonmetastatic squamous lung cancer (1.02 versus 0.61 ng/ml; P < 0.05). sCD40L levels significantly correlated with sP-selectin (P < 0.001), prothrombin fragment 1 + 2 (P < 0.001), or thrombin-antithrombin III complex (P < 0.05) in squamous lung cancer, but only sP-selectin (P = 0.011) was independently related to sCD40L.

Conclusions: These findings indicate that elevated sCD40L levels can be preferentially found in patients with advanced squamous cancer and provide evidence that increased levels of this cytokine are associated to the occurrence of in vivo platelet activation.