bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 2988: Regulation of mitosis and taxane response by Daxx
Authors: Giovinazzi Serena , Lindsay Cory , Morozov Viacheslav , Han Hyo , Ishov Alexander 
Published: June 2012

Abstract
Current theories suggest that mitotic proteins are essential for cellular response to taxanes (paclitaxel and docetaxel), a widely-used family of chemotherapeutic compounds. We found that absence or depletion of protein Daxx increases cellular resistance to paclitaxel _a common trait of patients diagnosed with breast cancer and other malignancies. Particularly, we observed that 1) paclitaxel induced cell death, in both human breast cancer and mouse cell lines, depends on the level of Daxx; 2) cells become paclitaxel-resistant upon experimental depletion of Daxx; 3) breast cancer specimens accumulate differential level of Daxx; 4) docetaxel response in breast cancer patients correlates with level of Daxx mRNA. We also found that Daxx is important for the proper progression of mitosis in human cells: duration of mitotic stages is altered in cells stably depleted of Daxx which also show increased stability of cyclin B1. Thus, protein Daxx, that was previously characterized as a transcription repressor and an apoptotic-related protein, may also have a novel function in mitosis progression as a prometaphase checkpoint release protein in control conditions and upon mitotic stress.
In order to understand the mechanism by which Daxx orchestrates mitosis progression and identify new potential targets responsible for taxane resistance, we adopted a functional proteomic approach to identify Daxx-associated mitotic complex. We optimized the protocol for Tag based affinity purification in a way to obtain Daxx expressed downstream of FLAG Tag in tandem with HA Tag (FH) and a Thrombin Cleavage Site (TCS). HEp2 cells transduced with pOZ-FH-TCS-Daxx and the empty pOZ-FH plasmid (control), synchronized by double thymidine block and next arrested in pro-metaphase with paclitaxel, were used to purify Daxx containing mitotic complex. Mitotic specific Daxx interacting proteins were identified by SDS-PAGE followed by mass spectrometry.
The functional characterization of newly identified Daxx mitotic partners will shed lights on the complex mechanism/phenomena of taxanes resistance and ultimately offer the molecular basis for successful treatment strategies of breast cancer patients.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2988. doi:10.1158/1538-7445.AM2011-2988
Abstract 2992: Mitotic role for Pten in accurate chromosome segregation
Authors: van Ree Janine H. , Jeganathan Karthik B. , Jin Fang , van Deursen Jan M. 
Published: June 2012

Abstract
During mitosis, sister chromatids are separated and equally divided over two daughter cells. If missegregation of whole chromosomes occurs, progeny cells with an abnormal number of chromosomes will arise. This is referred to as aneuploidy, a hallmark of most human cancers.
We found that inactivation of a single Pten allele in mouse splenocytes and mouse embryonic fibroblasts (MEFs) is sufficient to cause aneuploidy, suggesting a role for Pten in the chromosome segregation process. Upon further study by live cell imaging of haploinsufficient and null Pten MEFs, we indeed found many missegregation errors (59% and 79% respectively, compared to 15% in wildtype MEFs). These abnormalities were independent from the AKT pathway since overexpression of a myristoylated, constitutively active form of AKT in wildtype MEFs resembled a wildtype instead of a Pten heterozygous phenotype. In addition, overexpression of a catalytic mutant Pten (C124S) in Pten+/- MEFs corrected the missegregation errors. We therefore propose a novel tumor-suppressive function of Pten to prevent whole chromosome instability, independent of the increased cell proliferation and survival caused by the activation of AKT.
BubR1 is a regulator of kinetochore-microtubule attachment and a potent inhibitor of Cdc20, a key co-activator of the anaphase promoting complex/cyclosome (APC/C) that drives cells into anaphase by targeting the anaphase inhibitors cyclin B1 and securin for degradation by the 26S proteosome. We found that overexpression of BubR1 completely restores accurate chromosome segregation in Pten+/- MEFs, alluding to a specific role for Pten in mitosis. As a first step to test the hypothesis that Pten's mitotic role in preventing aneuploidization represents a key tumor suppressive function of this phosphatase, we bred a Flag-tagged BubR1 transgene into Pten+/- mice. We are currently in the process of studying the impact of the transgene on the development of prostatic intraepithelial neoplasia (PIN). Consistent with our hypothesis, preliminary analysis of two mice shows that BubR1 overexpression considerably decreases PIN lesion multiplicity. Data from the complete analysis of our double transgenic mouse cohort will be presented at the meeting.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2992. doi:10.1158/1538-7445.AM2011-2992
Abstract 2999: Role of heterogeneous nuclear ribonucleoprotein A/Bs in telomere maintenance
Authors: Wang Tzu-Chien V. , Huang Pei-Rong , Yeh Yuan-Ming , Hung Shu-Chen 
Published: June 2012

Abstract
Heterogeneous nuclear ribonucleoproteins (hnRNPs) constitute a large family of proteins that associate with nascent pre-mRNAs, packaging them into hnRNP particles. In addition to their action as RNA-binding proteins, several members of the hnRNP family are thought to play roles in telomere maintenance because they are known to bind to telomeric DNA and to TERRA RNA, which is now identified as an integral component of telomeric heterochromatin. Using affinity purification and proteomic approach, we have previously shown that the members of hnRNP A/B family are the most abundant proteins in the nuclear extracts that bound specifically to G-strand telomeric DNA. To address if members of hnRNP A/B family are essential components of a functional telomere (i.e., does hnRNP A/Bs play a structural role) and to determine the functional overlap among members of hnRNP A/Bs in telomere length regulation, we initiated to investigate the biological effects of single, double, or triple knock-down of hnRNP A1, A2/B1 or A3. Preliminary results obtained from transient depletion of single hnRNP A1, A2 or A3 by RNA interference (RNAi) indicated that depletion of hnRNP A2 or A3 significantly reduced cell growth and colony formation. The percentage of cells in the sub-G1 phase was increased following the knockdown of hnRNP A2 or A3. In addition, the expression of S-phase kinase-associated protein-2 (skp2) was decreased in the transient knock-down cells. Surprisingly, however, studies of stable clones derived from single knock-down experiments indicated that knock-down of hnRNP A2, but not A1 or A3, produced a profound effect on cellular growth. This effect does not appear to result from reduced viability and/or apoptosis. We noted that an increased expression of hnRNP A1 was always observed in the stable clones depleted of hnRNP A3. Similarly, increased expression of A3 was observed in the cells depleted of hnRNP A1, suggesting that hnRNP A1 and A3 may have functional redundancy in vivo. Works are in progress to determine whether the anti-proliferation effects of depleting hnRNP A/B may result from telomere dysfunction, and to investigate the functional overlap between hnRNP A/Bs using double knock-down approach.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2999. doi:10.1158/1538-7445.AM2011-2999
Abstract 3013: Study of three-dimensional cell culturing influence on DNA methylation profile
Authors: López-Serra Paula , Martín-Subero Ignacio , Esteller Manel 
Published: June 2012

Abstract
In this study, we purpose the analysis of the DNA methylation profile of four different human breast cell lines, two non transformed and two tumoral, taking into account the influence of the environment in cell culturing.
The extracellular matrix was initially thought to serve as nothing more than a physical support for the cells. However, nowadays is very well known that the extracellular matrix is a key component in cell biology, regulating cell biology and tissue homeostasis. This suggests that there is a bidirectional crosstalk between the cells and the surrounding extracellular matrix.
Cell culturing is a commonly used technique in all areas of biology research. Usually, adherent cells are spreading in two-dimensional plates where they growth attached to the plastic surface in two directions. Mammary epithelial cells that are cultured on this conventional way fail to form acinar-like structures and loss tissue specific protein expression. Many of the microenvironment influences can be restored in cell culturing models by using three-dimensional cultures in extracellular matrix gels. 3D culturing of epithelial cells can help to reconstruct the acinar morphology seen in vivo and restore some mammary-specific function, like milk proteins production.
DNA methylation plays a significant role in the epigenetic regulation of chromatin structure and gene expression. In this work, we tried to analyze the DNA methylation profile of four different human breast cell lines growth in 2 and 3 dimensions to assess the influence of DNA methylation in the two models. HMEC (finite lifespan human mammary epithelial cell line), MCF10A (spontaneously immortalized, but not transform, human breast epithelial cell line), MCF7 (human breast adenocarcinoma cell line, metastasic) and MDA-MB-231 (human breast adenocarcinoma cell line, metastasic) were growth in plates with and without MatrigelTM basement Membrane Matrix Growth Factor Reduced (BD). 3D culturing was done by spreading the cells in the matrix surface and allowing them to form the characteristic acini of the mammary gland. Morphological differences are evident between the 2 and 3D culture models, being much more accurate the 3D model from a phenotypic point of view. DNA mehtylation status was done by illumina's Infinium Microarrays, comparing the methylation profile of each cell line growth in 2 and 3D. We determined in this way which genes are differentially methylated in 2 and 3 dimensions.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3013. doi:10.1158/1538-7445.AM2011-3013
Abstract 3014: Quantitative accuracy of Illumina HumanMethylation27 Infinium BeadChip data assessed by pyrosequencing
Authors: Huang Zhiqing , Yamaguchi Ken , Berchuck Andrew , Murphy Susan K. 
Published: June 2012

Abstract
Purpose. Aberrant DNA methylation can lead to changes in gene expression, and this alteration is highly relevant in the context of cancer. The ability to accurately assess DNA methylation status is therefore of great importance in health and disease. The Illumina HumanMethylation27 Infinium BeadChip allows for analysis of whole genome DNA methylation by interrogating the methylation status of 27,578 CpG sites from the promoter regions of 14,475 annotated genes. However, one potential limitation of this platform as specified by the manufacturer is the inability to detect a β value difference between specimens of &lt;0.2 (∼20% methylation). The present study assessed the quantitative nature of the Infinium platform through independent validation using a pyrosequencing approach.
Procedures. Genomic DNA from 46 ovarian cell lines and 4 cultured normal cells, including ovarian surface epithelium and endometriotic cells, was modified with sodium bisulfite using the EZ DNA methylation kit from Zymo Research. Bisulfite conversion efficiency was confirmed by pyrosequencing at two chromosomal loci. Comparisons between normal and cancer cells identified differentially methylated genes using criteria of p0.3. Ten candidate differentially methylated genes (C14orf105, HNF1 β, HNF1α, KIF12, MIA2, PAX8, SERPINA6, SGK2, SRC, and TM4SF4) were selected for validation. Pyrosequencing assays were designed to allow for direct comparison of the same CpG site(s). The relationship between pyrosequencing and Infinium data was evaluated using correlation analyses.
Results. Bisulfite conversion was &gt;97% at BRCA1 (chr17) and IGF2 (chr11). Hypermethylation of 1,162 genes (1,452 CpG sites) and hypomethylation of 63 genes (74 CpG sites) was found in ovarian cancer cell lines as compared with cultured normal cells. The β values for 10 genes from Infinium analysis and percent methylation by pyrosequencing of the same CpG site(s) were highly correlated (R&gt;0.98, p0.91, p&lt;0.001). There was a significant positive correlation between platforms when data for all ten genes were grouped into 0-20%, 21-40%, 41-60% 61-80% and 81-100% bins (R value range, 0.32-0.73; p&lt; 0.00002).
Conclusions. Ovarian cancer cell lines exhibit significantly increased methylation as compared with normal cultured cells using the HumanMethylation27 Infinium BeadChip assay. The strong correlations between the Infinium and pyrosequencing data at the same CpG sites suggest that the Infinium platform is quantitative, lending support for use of this technology for assessment of methylation differences among specimens analyzed.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3014. doi:10.1158/1538-7445.AM2011-3014
Abstract 3015: DNA methylation biomarkers for lung cancer diagnostics: Validation in bronchial washings
Authors: Liloglou Triantafillos , Nikolaidis George , Raji Olaide , Field John Kirpatrick 
Published: June 2012

Abstract
Epigenetic reprogramming is a characteristic of virtually of lung tumors. DNA methylation is unique for biomarker utilization in body fluids due to its chemical stability and the high frequency of abnormal hypermethylation in lung tumors. Despite the evidence from a wide range of studies in this field, very little is progressing to clinical exploitation, mainly due to the insufficient preclinical and clinical validation. In this study we have undertaken extensive preclinical validation of DNA methylation biomarkers in bronchial washings from 320 lung cancer cases and 320 age/sex matched controls organized in training (n=150 in each arm) and validation (n=170 in each arm) sets. Quantitative methylation specific PCR (qMSP) assays were developed and optimized through multiple sets of methylation standards. The hypermethylation detection threshold was set to 0.5% based on the reproducibility of signal detection.
Among the promoters tested p16, RASSF1, WT1, RARbeta, TERT and CYGB proved to be highly discriminating between cases and controls while CDH13, TMEFF2, p73 and DAPK did not demonstrate a significant difference. Using a criterion of at least two positives from the discriminating markers in the validation set, this panel of six markers demonstrated an overall 70.5% sensitivity and 97.7% specificity. It is of note that when combining methylation biomarker with cytology, the positive detection rate was 81.5%. Regarding tumor histology, the detection sensitivity (combining training and validation sets) was higher in small cell carcinomas (95.1%) and squamous carcinomas (65.2%) than in adenocarcinomas (51.6%).
Our results clearly demonstrate the clinical potential of DNA methylation in lung cancer diagnostics, although it is profound that this panel must be enriched by additional promoters. It also becomes apparent that combined multi-center studies of increased statistical power must be undertaken in order to promptly validate biomarker panels for clinical implementation.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3015. doi:10.1158/1538-7445.AM2011-3015
Abstract 304: Predictive factors of pathological complete response by neoadjuvant chemotherapy for operable breast cancer
Authors: Ishikawa Takashi , Shimizu Daisuke , Sasaki Takashi , Morita Satoshi , Tanabe Mikiko , Ota Ikuko , Kawachi Kae , Chishima Takashi , Ichikawa Yasushi , Endo Itaru 
Published: June 2012

Abstract
Background: Nonanthracycline regimens with taxanes have become to be used more frequently than before. Thus, it has become important to consider sensitivities to these two drugs in individual patients.
Aim: To examine the association between the pathological response of each regimen and several pathological factors and whether individualized treatment based on HER2 may improve the overall pathological effects.
Patients and methods: 1) Retrospective study: 170 patients treated with standard regimens consisted of anthracycline and/or taxan prior to surgery. 2) Prospective study: 18 patients with HER2 overexpression received 4 cycles of anthracycline and cyclophosphamide (AC), while 45 pathients without HER2 expression received 4 cycles of docetaxel and cyclophosphamide (TC). For these 2 studies, the overall pCR rates were examined. The association of pCR with pathological factors including estrogen- and progesterone-receptor (ER and PgR), HER2, nuclear grade, Ki-67, P-53 and Topoisomerase IIα (TopoIIα) etc. were also examined.
Results: 1) The overall pCR rate was 24.2 % (41/170). Multivariate analysis with factors revealed that ER and nuclear grade were significantly associated with pCR. 2) The overall pCR rate was 36.5% (23/63), with pCR rates of 27.8% (5/18) and 40.0% (18/45) for the AC and TC regimens, respectively. TC regimen induced a pCR in most triple-negative cancer cases (15/19). Only low expression of ER maintained statistical significance as a predictor of pCR for the TC regimen.
Conclusions: Individualized HER2-based treatment improved the efficacy of neoadjuvant chemotherapy, probably because HER2 is, at least at present, the most promising predictor for the efficacy of anthracyclines. Further studies with predictive factors including TopoIIα by FISH are now under investigation.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 304. doi:10.1158/1538-7445.AM2011-304
Abstract 3053: Receptor tyrosine kinase AXL as a new target for prostate cancer therapy
Authors: Paccez Juliano D. , Vasquez Gabriela , Tamura Rodrigo E. , Duncan Kristal , Vasconcellos Jaira , Wiesner Theresa , Libermann Towia , Zerbini Luiz F. 
Published: June 2012

Abstract
Axl is a receptor tyrosine kinase of the family of TAM receptors (which includes TYRO3 and MER) and plays roles in different types of cancer. It is highly expressed in metastatic colon carcinoma, gastric, uterine endometrial and certain types of breast cancer, and sarcoma. As Axl is upregulated in several metastatic cell types it may play a role during invasion and metastasis. Tyrosine kinases (TKs) represent a major class of proto-oncogenes and are involved in tumor growth as well as progression and metastasis of cancer cells. TKs are being actively studied as targets for therapeutic intervention and several of this tyrosine kinase have shown efficacy in clinical trials. Prostate cancer has become the most common solid cancer in older men and is one of the most frequent causes of cancer deaths. Although androgen ablation therapy, surgery and radiation therapy are effective for the treatment of local prostate cancer, there is no effective treatment available for patients with the metastatic androgen-independent disease.
In this work we demonstrated the role of Axl in prostate cancer progression. Using real time PCR to access the level of several tyrosine kinase receptors expression in prostate cancer cell and human tissue, we have identified the tyrosine kinase receptor Axl as a potential target for prostate cancer therapy. Axl has consistent overexpression across prostate cancer cell lines and human prostate tumor tissue providing a model for testing the targeting of Axl. Preliminary data shows a significant increase of Axl expression was found in metastatic PCa cells and clinical samples (48% of adenocarcinomas of prostate when compared with normal prostate tissue). Interestingly, microarray analysis in addition to pathway analysis of PCa cells infected with lentivirus encoding siRNA against Axl revealed that some survival pathways are inhibited, but strikingly all members of the NF-κB pathway are down regulated. Furthermore, the blockage of Axl gene expression strongly inhibits proliferation, migration and invasion of PCa cells. Pilot studies in animal models demonstrate that inhibition of Axl reduces dramatically tumor formation. since our xenograft subcutaneous model in MF5 nude mice demonstrate that blockage of Axl reduces tumor formation by 49.5%.
Taken together these data demonstrated that Axl plays role for migration, invasion and tumor development and can be used as marker for invasive and metastatic tumors. Our data also indicates that Axl can be used as a target for drug therapies since its inhibition leads to induction of apoptosis and blocks cell proliferation.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3053. doi:10.1158/1538-7445.AM2011-3053