bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of Familial Non-BRCA1/2Breast Tumors by Loss of Heterozygosity and Immunophenotyping
Authors: Oldenburg Rogier A. , Kroeze-Jansema Karin , Meijers-Heijboer Hanne , van Asperen Cristi J. , Hoogerbrugge Nicoline , van Leeuwen Inge , Vasen Hans F.A. , Cleton-Jansen Anne-Marie , Kraan Jaennelle , Houwing-Duistermaat Jeanine J. , Morreau Hans , Cornelisse Cees J. , Devilee Peter 
Published: March 2006

AbstractPurpose: Since the identification of BRCA1 and BRCA2, there has been no major breast cancer susceptibility gene discovered by linkage analysis in breast cancer families. This has been attributed to the heterogeneous genetic basis for the families under study. Recent studies have indicated that breast tumors arising in women carrying a BRCA1 mutation have distinct histopathologic, immunophenotypic, and genetic features. To a lesser extent, this is also true for breast tumors from BRCA2 carriers. This indicates that it might be possible to decrease the genetic heterogeneity among families in which BRCA1 and BRCA2 have been excluded with high certainty (BRCAx families) if distinct subgroups of BRCAx-related breast tumors could be identified.Experimental Design: Loss of heterozygosity (LOH) analysis with at least one marker per chromosomal arm (65 markers) was used to characterize 100 breast tumors derived from 92 patients from 42 selected BRCAx families. In addition, the immunophenotype of 10 markers was compared with that of 31 BRCA1- and 21 BRCA2-related breast tumors.Results and Conclusions: The BRCAx-related tumors were characterized by more frequent LOH at 22q relative to sporadic breast cancer (P &lt; 0.02), and differed significantly from BRCA1- and BRCA2-related tumors in their positivity for Bcl2. However, cluster analyses of the combined data (LOH and immunohistochemistry) did not result in subgroups that would allow meaningful subclassification of the families. On chromosomes 2, 3, 6, 12, 13, 21, and 22, we found markers at which LOH occurred significantly more frequent among the tumors from patients belonging to a single family than expected on the basis of overall LOH frequencies. Nonetheless, linkage analysis with markers for the corresponding regions on chromosomes 12, 21, and 22 did not reveal significant logarithm of the odds.
Defective Antitumor Function of Monocyte-Derived Macrophages from Epithelial Ovarian Cancer Patients
Authors: Gordon Ilyssa O. , Freedman Ralph S. 
Published: March 2006

AbstractPurpose: Monocytes/macrophages (MO/MA) are an important but heterogeneous population of immune inflammatory cells that have diverse effector functions. We examined and compared these differences in peripheral blood and ascites of epithelial ovarian cancer patients with peripheral blood of normal donors.Experimental Design: Comparisons were made of cell surface subsets, cytokine production, and FcR-dependent cytotoxicity of CD14+ MO/MA and the CD14brightCD16−HLA-DR+ MO/MA subset in normal donor peripheral blood and peripheral blood and ascites from epithelial ovarian cancer patients. Studies were done on monocyte-derived macrophages cultured with macrophage colony-stimulating factor and activated with lipopolysaccharide or a combination of lipopolysaccharide plus recombinant IFN-γ.Results: We determined that MO/MA or its subset from epithelial ovarian cancer patients had altered morphology and significantly less antibody-dependent cell-mediated cytotoxicity and phagocytic activity than did MO/MA from normal donors. Our findings also showed that monocyte-derived macrophages from both epithelial ovarian cancer patients and normal donors produce macrophage colony-stimulating factor–stimulated cytokines, including interleukin-8, tumor necrosis factor-α, and interleukin-6.Conclusions: These findings highlight for the first time the defective antibody-dependent cell-mediated cytotoxicity and phagocyte functions of epithelial ovarian cancer–associated MO/MA, which could have implications for immunobiotherapeutic strategies.
Prognostic Significance of Basal-Like Phenotype and Fascin Expression in Node-Negative Invasive Breast Carcinomas
Authors: Rodríguez-Pinilla Socorro María , Sarrió David , Honrado Emiliano , Hardisson David , Calero Francisco , Benitez Javier , Palacios José 
Published: March 2006

AbstractPurpose: Basal-like phenotype tumors are frequently found among BRCA1 germ-line mutated breast carcinomas. They are biologically aggressive and have a tendency towards visceral metastasis when untreated. Nevertheless, it has been suggested that they respond to chemotherapy better than other types of tumors. Fascin expression has been associated with lung metastasis in breast cancer. The aim of this study was to determine whether basal-like phenotype and fascin were related in both sporadic and familial tumors and with prognosis in node-negative sporadic breast cancers.Experimental design: 230 nonfamilial and 28 hereditary node-negative invasive breast carcinomas were immunohistochemically analyzed using tissue microarrays. Tumors that were estrogen receptor/HER2 negative and cytokeratin 5/6 and/or epidermal growth factor receptor positive were considered to have a basal-like phenotype.Results: A basal-like phenotype was found in 11.9% of sporadic cancers. Among patients not receiving adjuvant chemotherapy, a basal-like phenotype was associated with poor prognosis (P = 0.001, log-rank test) whereas no such association was found in patients receiving it. Tumors with a basal-like phenotype showed local recurrence (17.4%) or visceral metastasis (13%) but not bone metastasis (P = 0.001). Fascin expression was observed in 25.1% of sporadic invasive breast carcinomas and was associated with the basal-like phenotype, but not with prognosis or recurrence pattern. Fascin was expressed in 83.3% and 16.7% BRCA1- and BRCA2-associated carcinomas, respectively (P = 0.048).Conclusions: Basal-like tumors had a tendency towards visceral metastasis and their prognosis was dependent on the use of postoperative chemotherapy. Although fascin expression was associated with the basal-like phenotype, it was not associated with their metastatic behavior. Fascin expression is frequent in BRCA1-associated tumors.
ErbB Receptor Signaling and Therapeutic Resistance to Aromatase Inhibitors
Authors: Shin Incheol , Miller Todd , Arteaga Carlos L. 
Published: March 2006

Abstract
We have investigated the effect of HER-2 overexpression on resistance to the aromatase inhibitor letrozole in MCF-7 breast cancer cells stably expressing cellular aromatase (MCF-7/CA). MCF-7/CA cells overexpressing HER-2 showed a &gt;2-fold increase in estrogen receptor (ER)–mediated transcriptional reporter activity upon treatment with androstenedione compared with vector-only control MCF-7/CA cells. Cotreatment with letrozole did not abrogate androstenedione-induced transcription and cell proliferation in HER-2-overexpressing cells. Chromatin immunoprecipitation assays using cross-linked protein-DNA from MCF-7/CA/HER-2 cells indicated ligand-independent association of the ERα coactivators AIB-1 and CBP to the promoter region of the estrogen-responsive pS2 gene. Upon treatment with androstenedione, there were increased associations of AIB1 and CBP with the pS2 promoter in the HER-2-overexpressing compared with control MCF-7/CA cells. These results suggest that ligand-independent recruitment of coactivator complexes to estrogen-responsive promoters as a result of HER-2 overexpression may play a role in the development of letrozole resistance.
Targeted Modulation of MGMT: Clinical Implications
Authors: Liu Lili , Gerson Stanton L. 
Published: March 2006

Abstract
O6-Methylguanine DNA methyltransferase (MGMT) has been studied for &gt;20 years as a gene that is associated with the mutagenicity and cytotoxicity induced by either methylating carcinogens or alkylating (methylating and chloroethylating) therapeutic agents. Pioneering studies of alkylating agents identified alkylated guanine at the O6 position, the substrate of MGMT, as a potentially promutagenic and lethal toxic DNA lesion. MGMT plays a prominent role in DNA adduct repair that limits the mutagenic and cytotoxic effect of alkylating agents. Because of its role in cancer etiology and chemotherapy resistance, MGMT is of particular interest. In this article, the clinical effect of MGMT expression and targeted modulation of MGMT will be summarized.
Blood Pharmacokinetics of Various Monoclonal Antibodies Labeled with a New Trifunctional Chelating Reagent for Simultaneous Conjugation with 1,4,7,10-Tetraazacyclododecane-N,N′,N″,N‴-Tetraacetic Acid and Biotin before Radiolabeling
Authors: Wang Zhongmin , Mårtensson Linda , Nilsson Rune , Bendahl Pär-Ola , Lindgren Lars , Ohlsson Tomas , Sjögren Hans-Olov , Strand Sven-Erik , Tennvall Jan 
Published: March 2006

Abstract
Purpose: Knowledge of the blood pharmacokinetics of monoclonal antibodies is crucial in deciding the optimal time for starting the administration of a “clearing agent” or using a “clearing device.” The primary purpose was to investigate whether the pharmacokinetics of various antibodies labeled with the same chelator and 111In differed significantly after i.v. injection in immunocompetent rats. A new trifunctional chelator called “1033” containing a biotin and a radiometal chelation moiety is introduced, making it possible to use only one conjugation procedure for the antibody.
Experimental Design: Sixty-five non–tumor-bearing rats were included and divided into four groups (I-IV). The blood pharmacokinetics was investigated for rituximab, BR96, and trastuzumab labeled with 1033 and 111In (I-III). The whole-body activity and activity uptake in muscle, liver, and kidney, which might explain differences in the early pharmacokinetics in blood, were also measured. hMN14 labeled with another chelator [1,4,7,10-tetraazacyclododecane-N,N′,N″,N‴-tetraacetic acid (DOTA)], but with the same radionuclide (111In-biotin-DOTA-hMN14), was studied (IV). The blood pharmacokinetics from another 15 tumor-bearing rats was compared with those of non–tumor-bearing rats (III) by injection of 111In-1033-BR96.
Results: No statistical difference was detected between the groups regarding the blood pharmacokinetics of rituximab, BR96, or trastuzumab. The pharmacokinetics and biodistribution of 111In-biotin-DOTA-hMN14 exhibited a clear difference compared with others. There were no significant differences in the blood pharmacokinetics of 111In-1033-BR96 between tumor-bearing rats and non–tumor-bearing rats.
Conclusions: Different antibodies labeled with the trifunctional chelator 1033 and 111In did not exhibit different blood pharmacokinetics, which means that the pharmacokinetics could be predicted irrespective of the IgG1 antibody chosen. A small tumor burden did not change the pharmacokinetics of the radioimmunoconjugates.
Improving the Delivery of Radionuclides for Imaging and Therapy of Cancer Using Pretargeting Methods
Authors: Sharkey Robert M. , Karacay Habibe , Cardillo Thomas M. , Chang Chien-Hsing , McBride William J. , Rossi Edmund A. , Horak Ivan D. , Goldenberg David M. 
Published: March 2006

Abstract
The article reviews the background and current status of pretargeting for cancer imaging and therapy with radionuclides. Pretargeting procedures were introduced ∼20 years ago as an alternative to directly radiolabeled antibodies. Because they were multistep processes, they were met with resistance but have since progressed to simple and improved procedures that could become the next generation of imaging and therapy with radionuclides. The separation of the radiolabeled compound from the antibody-targeting agent affords pretargeting procedures considerable flexibility in the radiolabeling process, providing opportunities for molecular imaging using γ- or positron-emitting radionuclides and a variety of β- and α-emitting radionuclides of therapeutic applications. Pretargeting methods improve tumor/nontumor ratios, exceeding that achieved with directly radiolabeled Fab′ fragments, particularly within just a few hours of the radionuclide injection. In addition, tumor uptake exceeds that of a Fab′ fragment by as much as 10-fold, giving pretargeting a greatly enhanced sensitivity for imaging. Advances in molecular biology have led to the development of novel binding proteins that have further improved radionuclide delivery in these systems. Studies in a variety of hematologic and solid tumor models have shown advantages of pretargeting compared with directly radiolabeled IgG for therapy, and there are several clinical studies under way that are also showing promising results. Thus, the next generation of targeting agents will likely employ pretargeting approaches to optimize radionuclide delivery for a wide range of applications.
Enhancement of the Therapeutic Index: From Nonmyeloablative and Myeloablative toward Pretargeted Radioimmunotherapy for Metastatic Prostate Cancer
Authors: DeNardo Sally J. , Richman Carol M. , Albrecht Huguette , Burke Patricia A. , Natarajan Arut , Yuan Aina , Gregg Jeff P. , O'Donnell R.T. , DeNardo Gerald L. 
Published: March 2006

Abstract
Purpose: New strategies that target selected molecular characteristics and result in an effective therapeutic index are needed for metastatic, hormone-refractory prostate cancer.
Experimental Design: A series of preclinical and clinical studies were designed to increase the therapeutic index of targeted radiation therapy for prostate cancer. 111In/90Y-monoclonal antibody (mAb), m170, which targets aberrant sugars on abnormal MUC1, was evaluated in androgen-independent prostate cancer patients to determine the maximum tolerated dose and efficacy of nonmyeloablative radioimmunotherapy and myeloablative combined modality radioimmunotherapy with paclitaxel. To enhance the tumor to liver therapeutic index, a cathepsin degradable mAb linkage (111In/90Y-peptide-m170) was used in the myeloablative combined modality radioimmunotherapy protocol. For tumor to marrow therapeutic index improvement in future studies, anti-MUC1 scFvs modules were developed for pretargeted radioimmunotherapy. Anti-MUC1 and anti-DOTA scFvs were conjugated to polyethylene glycol scaffolds tested on DU145 prostate cancer cells and prostate tissue arrays, along with mAbs against MUC1 epitopes.
Results: The nonmyeloablative maximum tolerated dose of 90Y-m170 was 0.74 GBq/m2 for patients with not more than 10% axial skeleton involvement. Metastatic prostate cancer was targeted in all 17 patients; mean radiation dose was 10.5 Gy/GBq and pain response occurred in 7 of 13 patients reporting pain. Myeloablative combined modality radioimmunotherapy with 0.4 GBq/m2 of 90Y-peptide-m170 and paclitaxel showed therapeutic effects in 4 of 6 patients and 30% less radiation to the liver per unit of activity. Neutropenia was dose limiting without marrow support and patient eligibility was a major limitation to dose escalation. Hypoglycosylated MUC1 epitopes were shown to be abundant in prostate cancer and to increase with disease grade. Anti-MUC1 scFvs binding to prostate cancer tissue and live cells were developed into di-scFv binding modules.
Conclusions: The therapeutic index enhancement for prostate radioimmunotherapy was achieved in clinical studies by the addition of cathepsin cleavable linkers to 90Y-conjugated mAbs and the use of paclitaxel. However, the need for marrow support in myeloablative combined modality radioimmunotherapy restricted eligible patients. Therefore, modular pretargeted radioimmunotherapy, aiming at improving the tumor to marrow therapeutic index, is being developed.
Radioimmunotherapy of Solid Tumors by Targeting Extra Domain B Fibronectin: Identification of the Best-Suited Radioimmunoconjugate
Authors: Berndorff Dietmar , Borkowski Sandra , Sieger Stephanie , Rother Axel , Friebe Matthias , Viti Francesca , Hilger Christoph S. , Cyr John E. , Dinkelborg Ludger M. 
Published: March 2006

Abstract
Purpose: The expression of extra domain B (ED-B) fibronectin is always associated with angiogenic processes and can be exclusively observed in tissues undergoing growth and/or extensive remodeling. Due to this selective expression, ED-B fibronectin is an interesting target for radioimmunotherapy of malignant diseases. The aim of this study was to identify the most appropriate ED-B-targeting radioimmunoconjugate for the therapy of solid tumors.
Experimental Design: Three ED-B fibronectin-binding human antibody formats of L19 were investigated: dimeric single-chain Fv (∼50 kDa), “small immunoprotein” (SIP, ∼80 kDa), and immunoglobulin G1 (IgG1, ∼150 kDa). These L19 derivatives were either labeled with I-125 or with In-111 (using MX-diethylenetriaminepentaacetic acid, MX-DTPA). Pharmacokinetics and tumor accumulation of the radiolabeled immunoconjugates were investigated in F9 (murine teratocarcinoma) tumor-bearing mice. Subsequently, dosimetry for the corresponding therapeutic isotopes I-13-1 and Y-90 was done. After testing the myelotoxicity of I-131-L19-SIP and I-131-L19-IgG1 in non-tumor-bearing mice, the therapeutic efficacy of these iodinated antibody formats was finally investigated in F9 tumor-bearing mice.
Results: The most favorable therapeutic index was found for I-131-L19-SIP followed by I-131-L19-IgG1. The therapeutic index of all In-111-labeled derivatives was significantly inferior. Considering the bone marrow as the dose-limiting organ, it was calculated that activities of 74 MBq I-131-L19-SIP and 25 MBq I-131-L19-IgG1 could be injected per mouse without causing severe myelotoxicity. The best therapeutic efficacy was observed using I-131-L19-SIP, resulting in significant tumor growth delay and prolonged survival after a single injection.
Conclusion: Compared with other L19-based radioimmunoconjugates, I-131-L19-SIP is characterized by superior antitumor efficacy and toxicity profile in the F9 teratocarcinoma animal model. These results indicate that ED-B fibronectin-targeted radioimmunotherapy using I-131-L19-SIP has potential to be applied to treatment of solid cancers.
Mechanisms of Cell Sensitization to α Radioimmunotherapy by Doxorubicin or Paclitaxel in Multiple Myeloma Cell Lines
Authors: Supiot Stephane , Gouard Sebastien , Charrier Josiane , Apostolidis Christos , Chatal Jean-Francois , Barbet Jacques , Davodeau François , Cherel Michel 
Published: March 2006

AbstractPurpose: The purpose of this study was to analyze different mechanisms (cell cycle synchronization, DNA damage, and apoptosis) that might underlie potential synergy between chemotherapy (paclitaxel or doxorubicin) and radioimmunotherapy with α radionuclides.Experimental Design: Three multiple myeloma cell lines (LP1, RMI 8226, and U266) were treated with 213Bi-radiolabeled B-B4, a monoclonal antibody that recognizes syndecan-1 (CD138) 24 hours after paclitaxel (1 nmol/L) or doxorubicin (10 nmol/L) treatment. Cell survival was assessed using a clonogenic survival assay. Cell cycle modifications were assessed by propidium iodide staining and DNA strand breaks by the comet assay. Level of apoptosis was determined by Apo 2.7 staining.Results: Radiation enhancement ratio showed that paclitaxel and doxorubicin were synergistic with α radioimmunotherapy. After a 24-hour incubation, paclitaxel and doxorubicin arrested all cell lines in the G2-M phase of the cell cycle. Doxorubicin combined with α radioimmunotherapy increased tail DNA in the RPMI 8226 cell line but not the LP1 or U266 cell lines compared with doxorubicin alone or α radioimmunotherapy alone. Neither doxorubicin nor paclitaxel combined with α radioimmunotherapy increased the level of apoptosis induced by either drug alone or α radioimmunotherapy alone.Conclusion: Both cell cycle arrest in the G2-M phase and an increase in DNA double-strand breaks could lead to radiosensitization of cells by doxorubicin or paclitaxel, but apoptosis would not be involved in radiosensitization mechanisms.
Role of p21waf1/cip1 in effects of oxaliplatin in colorectal cancer cells
Authors: Hata Taishi , Yamamoto Hirofumi , Ngan Chew Yee , Koi Minoru , Takagi Akimitsu , Damdinsuren Bazarragchaa , Yasui Masayoshi , Fujie Yujiro , Matsuzaki Takeshi , Hemmi Hiromichi , Xu Xundi , Kitani Kotaro , Seki Yosuke , Takemasa Ichiro , Ikeda Masataka , Sekimoto Mitsugu , Matsuura Nariaki , Monden Morito 
Published: March 2006

Abstract
Clinical studies have shown that oxaliplatin, a novel platinum derivative, is a potent chemotherapeutic agent for colorectal cancer when combined with 5-fluorouracil and leucovorin. Although the toxic activity is based on covalent adducts between platinum and DNA, its actual biological behavior is mostly unknown. In an effort to explore the mechanism of tumor susceptibility to oxaliplatin, we examined the cytotoxic effects of oxaliplatin in colorectal cancer cell lines in reference to p53 gene status. Although p53 gene status did not clearly predict sensitivity to oxaliplatin, p53 wild-type cells including HCT116 were sensitive but HCT116 p53−/− were found to be resistant to oxaliplatin. Oxaliplatin caused strong p21waf1/cip1 induction and G0-G1 arrest in p53 wild-type cells, whereas cisplatin did not induce G0-G1 arrest. Assays using p53 wild but p21waf1/cip1 null HCT116 cells revealed that oxaliplatin did not show G0-G1 arrest and reduced growth-inhibitory effects, suggesting that p21waf1/cip1 may be a key element in oxaliplatin-treated p53 wild-type cells. Although HCT116 is DNA mismatch repair–deficient, a mismatch repair–proficient HCT116+ch3 cell line displayed similar responses with regard to p21waf1/cip1-mediated growth inhibition and G0-G1 arrest. In p53 mutant cells, on the other hand, oxaliplatin caused an abrupt transition from G1 to S phase and eventually resulted in G2-M arrest. This abrupt entry into S phase was associated with loss of the p21waf1/cip1 protein via proteasome-mediated degradation. These findings suggest that p21waf1/cip1 plays a role in oxaliplatin-mediated cell cycle and growth control in p53-dependent and -independent pathways.
Naloxone acts as an antagonist of estrogen receptor activity in MCF-7 cells
Authors: Farooqui Mariya , Geng Zhen H. , Stephenson Elliot J. , Zaveri Nurulain , Yee Douglas , Gupta Kalpna 
Published: March 2006

Abstract
Estrogen promotes the growth of breast cancer via estrogen receptors (ER). Earlier studies showed that the opioid receptor antagonist naloxone inhibits MCF-7 breast cancer growth in mice. We examined the cellular and molecular mechanism of naloxone antagonism of ERα activity in human MCF-7 cells. Naloxone (100 nmol/L) inhibited 17β-estradiol (E2)–induced (10 nmol/L) MCF-7 cell proliferation by 65% and mitogen-activated protein kinase/extracellular signal-regulated kinase phosphorylation. Naloxone blocked the E2-induced activation of ERα, with 85% inhibition after 5 minutes and 100% recovery after 60 minutes. This assay is based on quantitation of E2-activated nuclear ERα binding to the immobilized coactivator peptide. A significant decrease in E2-induced ERα transactivation was observed in the presence of naloxone in the estrogen response element-luciferase reporter assay (P &lt; 0.05, E2 versus E2 + naloxone). Naloxone also blocked E2-induced down-regulation of ERα mRNA at 30 minutes and 6 hours. Although naloxone inhibits ERα activity directly, it also induces a cross-talk between μ-opioid receptor (MOR) and ERα. Immunoprecipitates with anti-MOR antibody showed the presence of ERα in cells incubated with E2 in the presence of naloxone but not in cells incubated with E2 or naloxone alone. Higher amounts of ERα associated with MOR after 60 minutes compared with 10 minutes of incubation. Naloxone inhibited E2-bovine serum albumin-FITC binding to plasma membrane–associated ERα and also inhibited the direct binding of [3H]E2 to ERα. Thus, naloxone modulates ERα activity directly as well as indirectly via MOR. This study suggests that naloxone-like compounds can be developed as novel therapeutic molecules for breast cancer therapy. [Mol Cancer Ther 2006;5(3):611–20]