bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 4323: ATP binding cassette transporters modulate both D-luciferin- and coelenterazine-based bioluminescence imaging
Authors: Huang Ruimin , Vider Jelena , Kochetkov Tatiana , Blasberg Ronald 
Published: February 2011

Abstract
Bioluminescence imaging (BLI) of luciferase reporters provides a relatively simple, cost-effective, and extremely sensitive means to image fundamental biological processes in cancer research, including tumor growth, angiogenesis and metastasis. Translocation of D-luciferin (the substrate for Click Beetle Red (cLuc) and Firefly (fLuc) luciferase), and coelenterazine (the substrate for Renilla (rLuc), and Gaussia (gLuc) luciferase), across the cellular membrane could affect BLI intensity in vivo. ATP-binding cassette (ABC) transporters are membrane-bound efflux pumps utilizing the energy from ATP hydrolysis. They are implicated in multidrug resistant phenotypes of tumor cells and may be cancer stem cell markers.
To investigate the effect of ABC transporters on luciferase-based BLI, we generated HEK-293 reporter cells with selective overexpression of different ABC transporters (ABCB1, ABCC1 and ABCG2) and different luciferases (cLuc, fLuc, rLuc and gLuc). In vitro studies showed that BLI signal intensity of intact cells compared to cell lysates decreased 89%, 77% and 75% when ABCG2 was overexpressed in HEK-293 cLuc, fLuc and rLuc reporter cells, respectively. No significant BLI change was observed in HEK-293 gLuc reporter cells with high expression of ABCG2. Overexpression of ABCB1 reduced BLI intensity only in HEK-293 rLuc reporter cells by 51%. ABCC1 overexpression did not affect BLI intensity in any of the HEK-293 reporter cells. These data indicate that ABCG2 affects BLI signal intensity generated from both D-luciferin and coelenterazine, and that ABCB1 affects coelenterazine (but not D-luciferin) signal intensity.
Selective ABC transporter inhibitors, Reversin 121 against ABCB1, MK-571 against ABCC1, and fumitremorgin C (FTC) against ABCG2, were applied in HEK-293 reporter cells with ABC transporter overexpression. Compared with vehicle treatment, FTC increased BLI intensity more than 2-fold in HEK-293 cLuc, fLuc and rLuc reporter cells; Reversin 121 elevated BLI intensity 2.1 fold only in HEK-293 rLuc reporter cells. BLI of xenografts derived from HEK-293 reporter cells with overexpression of ABC transporters confirmed the results of inhibitor treatment in vivo.
These findings demonstrate that ABC transporters can significantly modulate intracellular delivery of luciferase-based substrates, and that endogenous expression of ABC transporters can significantly affect BLI readout, both in vitro and in vivo. In this context, the BLI-based assay can provide a high throughout platform to screen the novel ABC transporter inhibitors for the improvement of antitumor therapy.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4323.
Abstract 4326: High-resolution imaging and antitumor effects of GFP(+) bone marrow-derived cells homing to syngeneic mouse colon tumors
Authors: Hart Lori S. , Finnberg Niklas , Dolloff Nathan G. , Rodgers Zachary B. , Dicker David T. , Thomas-Tikhonenko Andrei , El-Deiry Wafik S. 
Published: February 2011

Abstract
Bone marrow-derived cells (BMDCs) are believed to play a significant role in the growth and spread of certain tumors, namely cancers of the breast, brain, lung, and stomach. To date there are limited reports of bone marrow involvement in colon cancer pathogenesis, but such findings have the potential to generate novel treatments for patients with colon cancer. We have established two mouse models (Balb/c and C57/BL6 backgrounds) for imaging BMDCs from whole tumor to single-cell resolution, whereby the bone marrow of lethally irradiated host animals is reconstituted with EGFP-expressing bone marrow cells from matched donors. The bone marrow transplants (BMTs) yield mice with fluorescently labeled bone marrow and BMDCs can subsequently be monitored within a tumor through optical imaging, as well as ex vivo techniques. We have confirmed successful BM reconstitution at six or more weeks following transplantation. At least six weeks after transplantation, surviving Balb/c and C57/BL6 transplanted mice were injected with CT26 mouse colon cancer cells and p53-deficient Ras/Myc-transformed colonocytes, respectively. We have found up to 45% of cells dissociated from the tumors are GFP-positive and we are currently working to identify the various BM lineages represented within these populations. Interestingly, we have found that tumor growth is reduced in BMT animals compared with untransplanted host mice, as well as EGFP-expressing BM donor mice. We are currently working to determine whether an immune response associated with the BMT might account for these apparent anti-tumor effects. It will clearly be important to separate the molecular and cellular (T cells, NK cells, macrophages, etc) basis of the anti-tumor effect of the BMDCs from any pro-tumorigenic effect that could be subverted for therapeutic gain. Additionally, as an extension of our model we are performing orthotopic cecal wall injections in order to determine whether microenvironmental nuances alter BM homing to the colon versus subcutaneous space. It is expected that the identified BMDCs will aid in the development of novel cancer therapeutic and delivery strategies.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4326.
Abstract 4330: Effects of isofluran anesthesia on bioluminescence measurements: impact on pharmacological assessment of antitumor activity of chemical entities
Authors: Schnell Christian R. , Arnal Samuel , Becquet Mike , Barbé Stephanie , Garcia-Echeverria Carlos , Cozens Robert 
Published: February 2011

Abstract
Bioluminescence imaging (BLI) has been used for several years in oncology research to quantify tumor growth. In order to allow immobilization during data acquisition, animals are usually anesthetized by isoflurane gas inhalation. However, anesthesia leads to modifications of many physiological parameters, and particularly decreases in heart rate, blood pressure and blood flow, leading to decrease of substrate availability. Thus, it can be postulated that anesthesia will impair bioluminescence read outs. This may in turn profoundly affect interpretation of compound activity based on BLI. We have investigated the difference in BLI measurements performed in conscious and anesthetized animals using subcutaneous xenografts (HCT116 colorectal and U87MG glioblastoma) and orthotopic (U87MG cells injected directly in the brain) models. Moreover, functional tumor vessel mapping and hypoxia stage were obtained using casting technology and HypoxyProbeTM, respectively. Anti-tumor activity of 5-fluorouracil and temozolomide were assessed in the HCT116 xenograft and U87MG orthotopic models, respectively. Our results have clearly demonstrated that in all tested tumor models, tumor growth and efficacy of different compounds were not affected by the regular anesthesia procedure used for bi-weekly BLI assessments. We found a good correlation between caliper and BLI over a wide range of tumor size in conscious mice. When BLI was measured in anesthetized mice, signal intensity dropped significantly up to 70%, impairing the assessment of the antitumor efficacy of 5-FU. A clear correlation to functional tumor vessel density was evidenced. In the U87MG tumors cells implanted intracranialy, we could clearly follow tumor growth over time using BLI readouts. Isoflurane did not impair BLI measurements or the efficacy profile of temozolomide. In conclusion, we can say that BLI measurements in conscious tumor bearing mice offers a better alternative for resolving pharmacologic queries without the confounding effects of anesthesia. Obviously, more extended studies over a wide range of tumor types will be needed to reinforce these conclusions. Moreover, a more quantitative approach to assess vessel density and distribution in the casts using micro-CT technologies would be pivotal.
Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4330.
Abstract 4335: Imaging of cancer stem cells with radiolabeled Hedgehog
Authors: Tworowska Izabela , Li Jessica , Mourtada Firas , Woodward Wendy , Sims-Mourtada Jennifer 
Published: February 2011

Abstract
Recent studies have shown that the majority of early disseminated cancer cells detected in the bone marrow of breast cancer patients have a putative breast cancer “stem cell-like” phenotype. Moreover, activation of stem cell pathways in cancer cells has also been associated with resistance to radiation and chemotherapy. Early detection of these micrometastatic “stem cell-like” cancer cells could allow for earlier commencement of aggressive treatment to minimize relapse and disease spread and to improve therapeutic outcome. However, there is currently no stem cell targeted method to detect this population in vivo. New imaging agents are needed for real-time, non-invasive detection of stem cell pathway activation in micrometastatic disease in breast cancer. The stem cell pathway Hedgehog (HH) is known to regulate cell cycle entry and proliferation of embryonic neural and mammary progenitor cells as well as self-renewal of malignant mammary stem cells. Furthermore, the hedgehog receptor PTCH is overexpressed on cancer stem cells compared to normal mammary stem cells. Therefore, we sought to radiolabel the natural hedgehog ligand, sonic (SHH) with the positron emitter Gallium 68 (68Ga) for detection of cancer stem cells by positron emission tomography (PET). Recombinant SHH ligand was conjugated to the bifunctional chelator DOTA. DOTA-SHH was obtained with a total yield of 45%-60% as assessed by HPLC. DOTA-SHH was further characterized using MALDI-MS, ESI-MS with purity &gt; 90%. The conjugate was radiolabeled with 68Ga, with radiochemical purity of &gt;98% and specific activity of 4.3E+05 MBq/gram (theoretical specific activity = 9.18E+09 MBq/gram) as assessed by ITLC and radioHPLC. 68Ga-DOTA-SHH maintains high receptor binding in breast cancer cells and cellular uptake was correlated with PTCH receptor expression levels. Addition of 100-fold excess cold SHH reduced cellular uptake by approximately 90%. PTCH receptor expression is increased in MCF-7 stem cell-enriching culture conditions (mammospheres) and cellular uptake of 68Ga-DOTA-SHH was approximately 12-fold higher in mammosphere MCF-7 cultures compared to the total cell population. These findings demonstrate that chemical modification and radiolabeling of SHH ligand is feasible. Our studies suggest that 68Ga-DOTA-SHH has potential for molecular imaging of breast cancer by PET. Additionally, our studies suggest that 68Ga-DOTA-SHH can potentially identify aggressive tumors that may be rich in cancer stem cells.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4335.
Abstract 4336: Fluorescence laparoscopy for high-resolution pancreatic tumor imaging in an orthotopic mouse model
Authors: Cao Hop S. Tran , Kaushal Sharmeela , Lee Claudia Y. , Snyder Cynthia S. , Thompson Kari J. , Horgan Santiago , Talamini Mark A. , Hoffman Robert M. , Bouvet Michael 
Published: February 2011

Abstract
We report here the development of fluorescence laparoscopy to image green fluorescent protein (GFP)-expressing pancreatic tumors in an orthotopic mouse model.
An orthotopic mouse model of human pancreatic cancer was established by injecting GFP-expressing MiaPaca-2 human pancreatic cancer cells into the pancreas of 6-week old female athymic mice. On post-operative day 14, the animals underwent a diagnostic laparoscopy using both white and fluorescent light. The fluorescence laparoscope was constructed by modifying a standard laparoscopic system in the following manner: a 480-nm short pass excitation filter was placed between the light cable and the laparoscope, and a 2-mm thick emission filter that allows leakage of 1% of the background light was placed between the laparoscope and the camera. The camera and recording system were replaced with a MultiCam 310C (UVP, Upland, CA) that allows variable exposure time and gain setting in the controlling software. The exposure time was set to 110 msec and the gain to 97. A 3-mm 0-degree laparoscope was used in the mice. The mouse's abdomen was gently insufflated to 2 mm Hg via a 22-gauge angiocatheter that was secured via a suture. After fluorescence laparoscopy, the animals were sacrificed, and the identified tumors were collected and processed for histology. The experiments were performed in triplicate.
Fluorescence laparoscopy allowed facile and rapid identification of the bright fluorescent tumors in the pancreatic body. By employing the specific parameters above mentioned, a clear background was visible along with the fluorescent tumor under the fluorescent light mode. This could proffer an advantage in allowing exact localization of the lesions, eliminating the need to flip back and forth between white and fluorescent lighting, under which the background is usually so darkened that it is difficult to maintain spatial orientation.
In summary, the use of fluorescence laparoscopy permits the facile, clear, and rapid identification and localization of tumors that are labeled with fluorescent proteins or other fluorophores. Fluorescence laparoscopy may thus play a useful role in the diagnosis and staging of pancreatic and other aggressive gastrointestinal cancers.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4336.
Abstract 4338: The follicle-stimulating hormone receptor: A new tumor vascular endothelial target for imaging and therapy in animal models
Authors: Radu Aurelian , Siraj Ahsan , Vacherot Francis , Thomas Regi , Fujii Dennis K. , Nunn Adrian D. , Ghinea Nicolae 
Published: February 2011

Abstract
The follicle stimulating hormone receptor (FSHR) is a cell surface receptor expressed in the adult human organism only in the ovary and testis by granulosa and Sertoli cells, respectively, and to a lower extent by the endothelial cells (ECs) of gonadal blood vessels. Here we report that FSHR is also expressed by the vascular ECs of some types of tumors in mice and it is accessible to ligands delivered intravenously. We analyzed by immunohistochemistry tumors generated in nude mice by injecting human cell lines and also tumors that occur in transgenic mice that express oncogenes. Consistent FSHR expression by the ECs has been found in mouse tumors generated by the human prostate cell line LNCaP, and in tumors that appear in the polyoma virus middle T oncogene mouse model of breast carcinogenesis. The most robust expression of FSHR by ECs was found in the xenograft tumors generated by injecting the cell line A431 derived from a human epidermoid carcinoma. In a few other tumor types the expression of FSHR by the tumor vascular ECs was less frequent or absent. We investigated also by immunohistochemistry in mouse models the relation between expression by ECs of FSHR and VEGFR2/KDR, a well established marker of angiogenesis. The possibility of using FSHR expressed by tumor ECs for targeted imaging and therapy was explored in mice that carried xenograft LNCaP tumors. We coupled anti-FSHR extracellular domain antibodies to gold particles and perfused the mice with the complexes for 20 minutes. The vasculature was subsequently washed by perfusion and the tissues have been fixed and processed for electron microscopy. Numerous FSHR-gold particles bound to the surface of the tumor endothelium were visible, while there were no particles attached to the ECs in the normal tissues (prostate and lung). The reported data are relevant in the context of our recent finding that FSHR is expressed by ECs in a wide range of human tumors (manuscript submitted). The mentioned animal models can be used to evaluate the potential of FSHR for targeted tumor imaging and therapy based on FSHR ligands delivered intravenously. The mouse models could be also useful for investigating the mechanism of induction of FSHR expression in the tumor ECs and its potential role in tumor growth.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4338.
Abstract 4349: The chromosome 17q oncogene LASP1 promotes metastatic dissemination of medulloblastoma
Authors: Remke Marc , Traenka Christopher , Korshunov Andrey , Bender Sebastian , Witt Hendrik , Northcott Paul A. , Scheurlen Wolfram , Reifenberger Guido , Taylor Michael D. , Kulozik Andreas E. , Lichter Peter , Butt Elke , Pfister Stefan 
Published: February 2011

Abstract
Medulloblastoma is the most common malignant brain tumor and one of the leading causes of cancer-related mortality in children. Treatment failure mainly occurs in children harboring tumors with microscopic or macroscopic metastases at the time of diagnosis, which typically show gain of 17q (often based on an isochromosome 17q), a common cytogenetic hallmark of intermediate and high-risk medulloblastoma.
To pinpoint the oncogene(s) targeted by 17q gain, mRNA expression profiling was carried out in primary tumors with and without this indicative aberration and identified LIM and SH3 protein 1 (LASP1) as one of the most up-regulated genes on chromosome 17q in tumors with 17q gain. LASP1 (earlier named MLN50) was initially identified from a cDNA library of nodal breast cancer metastases and is highly expressed in more than 50% of metastatic human breast cancer, ovarian cancer, and hepatocellular carcinoma. In our study in medulloblastoma, a strong association of LASP1 mRNA abundance with 17q gain and metastatic disease at diagnosis was confirmed by quantitative real-time PCR in an independent cohort of 101 primary tumor samples. Protein expression was analyzed by immunohistochemistry in a large cohort of patients (n=207). High LASP1 protein expression was found to be strongly correlated with 17q gain, metastatic dissemination, and inferior overall and progression-free survival confirming our results on transcript level. Furthermore, multivariate analyses revealed LASP1 protein expression as an independent novel prognostic marker for overall survival and tumor progression in medulloblastoma. In vitro experiments in three established medulloblastoma cell lines demonstrate a strong reduction of cell migration and decreased proliferation upon LASP1 knockdown via siRNA, further indicating a functional role for LASP1 in the progression and metastatic dissemination of medulloblastoma.
In conclusion, we have identified LASP1 as an important player in the metastatic dissemination of medulloblastoma which additionally has a high potential to serve as a molecular biomarker for outcome prediction in future prospective studies. Furthermore, LASP1 comprises a promising novel candidate molecule for future targeted therapy approaches in high-risk medulloblastoma.
Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4349.
Abstract 435: Reduction of the invasive phenotype of SNAI overexpressing human breast cancer cells by peptide aptamer-mediated inhibition of SNAI protein functions
Authors: Bailey Charvann K. , Mittal Mukul K. , Misra Smita , Chaudhuri Gautam 
Published: February 2011

Abstract
Two members of the SNAI superfamily of zinc-finger transcriptional repressors: SNAI1 (also known as SNAIL) and SNAI2 (also known as SLUG) are implicated in the induction of aggressiveness and metastatic phenotypes in human breast cancer cells. SNAI1 and SNAI2 are very similar in their amino acid sequences at the C-terminal zinc-finger domains, but the N-terminal repressor domain is somewhat different. SNAI2 has two essential sub-domains, SNAG and SLUG domains, required for its repressor activity. The SNAG domain is also important in SNAI1. We have developed a recombinant protein containing thioredoxin, a tri-repeat of SNAG and SLUG domains of SNAI2 and a membrane translocation motif (MTM; AAVLLPVLLAAP) for the protein to be targeted to the nucleus. We expressed and purified this protein from E. coli using the His-patch thiofusion expression system (Invitrogen). When delivered to MDA-MB-231 and BT549 cells, this aptamer inhibited the functions of the SNAI proteins. The effect of SNAI protein knockdown by the peptide aptamer on the transformed phenotypes of these cells was evaluated by investigating the following parameters: (i) Measurement of doubling time and saturation density by plating cells and performing daily counts. (ii) Evaluation of cellular proliferation by measuring incorporation of 5′-bromodeoxyuridine into logarithmically growing cells. (iii) Determination of anchorage-independent growth in soft agar assays and analysis of the number and size of colonies formed. (iv) Evaluation of the cellular migration in scratch assays and in modified Boyden Chamber/transwell migration assays (directional migration). (v) Measurement of cellular invasion in vitro by using Matrigel-coated chambers. (vi) Assessment of the sensitivity to anoikis by plating cells on poly-HEMA coated plates and determination of cells undergoing apoptosis with propidium iodine staining or annexin labeling and flow cytometric analysis. (vii) Performing 3D culture assays to analyze invasiveness, proliferation or matrix degradation. All these data indicated reduction of the invasive phenotypes of the SNAI protein over expressing highly aggressive and metastatic human breast cancer cells by the peptide aptamer. Wrapsome-mediated targeted delivery of this aptamer alone or with other drugs may be used to reduce the progression of breast cancer. Supported by the DOD-CDMRP IDEA Grant# W81XWH-06-1-0466 and the Susan G. Komen Breast Cancer Foundation grant# BCTR0707627 to GC.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 435.