bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 1530: Dissecting breast cancer dormant CTC phenotypes
Authors: Vishnoi Monika , Peddibhotla Sirisha , Yin Wei , Xue Zhong , Scamardo Antonio T. , George Goldy C. , Hong David S. , Marchetti Dario 
Published: July 2016

Abstract
Tumor relapse is a clinically relevant problem in breast cancer where patients are asymptomatic because disseminated cells appear to become dormant for periods longer than 20 years and are undetectable by current clinical tools. Uncovering phenotypes of circulating tumor cells (CTCs) - the “seeds” of intractable metastasis-offers the promise to dissect CTC heterogeneity in relation to metastatic competence, to predict biomarker assessment, and to significantly improve monitoring and treatment of cancer. However, little is known about CTC biology and how CTCs differ in their capacity to circulate while maintaining a metastatic potential. We hypothesized that EpCAM-negative breast cancer CTC subsets exist, and avoid organ arrest with extreme efficiency by the concomitant presence of quiescence and stem cell properties. We collected peripheral blood of clinically diagnosed breast cancer patients with or without brain metastasis, and performed multiparametric flow cytometry to isolate EpCAM-negative CTC subsets with stem-cell properties (CD44+/CD24-), along with combinatorial expression of two neoplastic markers: urokinase plasminogen activator receptor (uPAR) and integrin beta1 (int β1). EpCAM-negative CTCs were further interrogated at a single-cell level employing DEPArray platform. Second, we were able to culture FACS-sorted CTC subsets, selected for six cell-surface expression markers (CD45-/EpCAM-negative/CD44+/CD24-/uPAR+/-/int β1+/-), as long-term in-vitro 3D CTC tumorspheres. Third, CTC subsets were interrogated for biomarker profiling and biological characteristics. We identified adhesive, proliferative and invasive properties of 3D CTC tumorspheres which were distinct per uPAR/int β1 combinatorial expression. Lastly, we performed next-generation whole-genome sequencing and mutation analyses to discover unique genomic signatures of uPAR/int β1 CTC subsets and verified as putative CTCs originally disseminated from primary breast tumor. Additional investigations are being pursued assessing the molecular and genomic characterization of uPAR/int β1 CTC subsets comprehensively. Clinical relevance of this research includes that this may enhance abilities to prospectively identify patients who may be at high-risk of developing breast cancer brain metastasis.
Citation Format: Monika Vishnoi, Sirisha Peddibhotla, Wei Yin, Zhong Xue, Antonio T. Scamardo, Goldy C. George, David S. Hong, Dario Marchetti. Dissecting breast cancer dormant CTC phenotypes. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1530.
Abstract 1537: The biological role of BAT-1 in prostate cancer
Authors: Garcia-Vargas Aileen M. , Juan-Rivera Maylein C. , Sánchez-Cordero Milaris M. , Sánchez-Vázquez Maria , Rohena Krizia , Martínez-Ferrer Magaly 
Published: July 2016

Abstract
Prostate cancer is the most common cancer in men in the United States and is the second cause of cancer death in men. In Puerto Rico, prostate cancer is the most common type of cancer and the leading cause of cancer death in men. The current available biomarkers are unable to predict malignant outcomes such as recurrence. Thus, there is a critical demand for the development of innovative diagnostic and prognostic tools for the management of prostate cancer. In the current study, we evaluated the biological role of BAT-1 in prostate cancer. Preliminary data from patients who had prostate cancer recurrence identified that HLA-B associated transcript 1 (BAT-1) was down-regulated in patients with prostate cancer recurrence when compared with non-recurrent patients. We down-regulated BAT-1 in PC3 and 22RV1 prostate cancer cell lines using small interfering RNA (siRNA). In vitro assays were performed to measure de-differentiation, proliferation, apoptosis, migration and invasion. Flow cytometry analysis using the cell Viability/Annexin V cell staining kit showed that down-regulation of BAT-1 significantly increased the proliferation of PC3 cells (P&lt;0.05) but decreased apoptosis. Down-regulation of BAT-1 showed no significant change in the expression of vimentin, desmin, and alpha-smooth muscle actin (α-SMA). Wound healing and Boyden assays showed that cells treated with BAT-1 siRNA significantly increased migration and motility at 12h and 24h of PC3 cells when compared to control (P&lt;0.05). Our results showed that BAT-1 down-regulation increased migration and cell motility. Cells also tend to proliferate more, but have reduced apoptosis. These results were expected due to its down-regulation in recurrent prostate cancer patient samples, suggesting that BAT-1 down-regulation promotes aggressiveness in prostate cancer recurrence. A possible mechanism of action for BAT1 is the modulation of cell proliferation and migration.
Citation Format: Aileen M. Garcia-Vargas, Maylein C. Juan-Rivera, Milaris M. Sánchez-Cordero, Maria Sánchez-Vázquez, Krizia Rohena, Magaly Martínez-Ferrer. The biological role of BAT-1 in prostate cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1537.
Abstract 154: Defective calcium signaling pathway highlights the mutational landscapes of liver metastasis from colorectal and breast cancer
Authors: Song Fangfang , Li Xiangchun , Liu Yuexin , Zheng Hong , Li Haixin , Wang Jun , Zhang Wei , Chen Kexin 
Published: July 2016

Abstract
Background
Imaging-based early detections of colorectal cancer (CRC) and breast cancer (BC) have significantly improved clinical outcome of these two common cancers. However, when metastasis to distant organs (e.g. liver) occurs, few therapeutic options are currently available. Recent advances in the next-generation sequencing technologies have revolutionized our possibilities to precisely profile all the genetic changes involved in the evolutionary process of individual cancers. To gain insight into genetic and molecular underpinning of metastasis, we performed whole exome sequencing of paired primary and metastases samples from seven CRC/BC patients. Candidate gene mutations were orthogonally validated by targeted sequencing on 28 paired samples including an additional 21 matched primary and metastatic tumors.
Results
We found that the mutational spectra of metastases were highly heterogeneous. A pairwise comparison between primary and metastatic samples indicated many point mutations were exclusively enriched either in primary tumor or metastases or were present in a sharing pattern between them, showing a lesion-specific genetic difference. Besides the known and novel mutations in APC, TP53, KRAS genes, we discovered 64 significantly mutated genes that were associated with liver metastases from CRC or BC, 9 of which were metastasis specific. Notably, genetic aberrations in calcium signaling pathway genes (GPR98, SYT6, TACR3, CYSLTR1, RYR3, and CACNA1A) were somatically mutated in liver metastases in 29% of CRC and BC cases, indicating that calcium-dependent signaling plays a key role in distant metastasis.
Conclusions
These results begin to define the genetic basis underlying liver metastasis from CRC/BC and identify potential therapeutic targets.
Citation Format: Fangfang Song, Xiangchun Li, Yuexin Liu, Hong Zheng, Haixin Li, Jun Wang, Wei Zhang, Kexin Chen. Defective calcium signaling pathway highlights the mutational landscapes of liver metastasis from colorectal and breast cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 154.
Abstract 1541: Heterogeneous response to platinum in metastatic ovarian cancer detectable by biodynamic imaging
Authors: Merrill Daniel , Sun Hao , Matei Daniela , Yakubov Bakhtiyor , Turek John , Nolte David 
Published: July 2016

Abstract
The mechanisms by which tumors develop multi-drug resistance are not well understood. Biodynamic imaging (BDI) is a label-free assay that detects phenotypic response of ex vivo tissue to chemotherapeutic drugs. In the current study, we used BDI to measure the response of primary and metastatic ovarian tumors to cisplatin. Xenografts from two human ovarian cancer cell lines, A2780 and SKOV3, were grown orthotopically in the ovaries of nude mice and allowed to metastasize in the peritoneal space. Primary and metastatic tumors were harvested and tested for response to 25 μM cisplatin by using BDI. Sensitivity was assessed through selected response biomarkers. Metastatic tumors of the platinum-sensitive A2780 cell line showed 20% decrease in sensitivity to cisplatin compared with the response of the primary tumors, while the less sensitive SKOV3 tumors exhibited a 6% decrease in response of metastatic vs. primary tumors. In parallel, RNA sequencing profiled primary ovarian and metastatic implants. Differential gene expression was detected in primary tumors vs. metastatic sites. Genes upregulated in metastases include TIMP3, WNT2, OSR1, elastin (SKOV3 tumor model) and MMP1, MMP3, MMP10, MET, EGFR, PDGF-C (A2780 tumor model). The study demonstrates the ability of BDI to detect differences in drug sensitivity between primary and metastatic tumors and provides support for the association of metastasis and chemoresistance in ovarian cancer. Supported by NIH R01 EB016582.
Citation Format: Daniel Merrill, Hao Sun, Daniela Matei, Bakhtiyor Yakubov, John Turek, David Nolte. Heterogeneous response to platinum in metastatic ovarian cancer detectable by biodynamic imaging. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1541.
Abstract 1569: IL6 mediated inflammatory loop reprograms normal to highly metastatic cancer stem cells at pre-HCC liver in β2SP+/- mice
Authors: Mitra Abhisek , Xia Xueqing , Mishra Lopa , Li Shulin 
Published: July 2016

Abstract
Hepatocellular carcinoma (HCC), the second-leading cause of cancer-related death world-wide, displays overexpression of the pro-inflammatory cytokine interleukin6 (IL6) and inhibition of transforming growth factor β (TGF-β) in its early phase. We aimed to identify the dynamics of liver immune cells under inflammatory conditions and to characterize early-phase tumor-initiating cells to comprehend aberrant molecular pathway(s) in HCC progression in a TGF-β disrupted murine model (β2SP+/-).
Methods: Chronic inflammation was induced in wild-type (WT) and β2SP+/- mice by hydrodynamic injection of IL6 (pIL6) encoding Sleeping Beauty transposons twice per month for 3 months. Liver stem cells were isolated by using CD133 antibody at the end of third month and cultured with suitable supplements.
Results: Culturing of stem cells enriched from WT and β2SP+/- mice treated with pIL6 showed that the stem cells derived from β2SP+/- mice were highly tumorigenic and metastatic in immune-deficient mice. Staining of these cells with EMT markers Twist and Slug were found in the nucleus. Immunophenotyping suggested that pIL6 treatment induced significant expansion and pro-inflammatory phenotypes of liver NKT and suppressed MDSCs in the β2SP+/- mice compared with WT to generate tumorigenic stem cells. By using numerous pharmacological inhibitors to identify aberrant molecular signaling event(s), we discovered constitutively activated nuclear factor κB (NF-κB) in these cancer stem cells (CSCs). Upon stable knockdown of NF-κB in the CSCs, both EMT phenotype and metastatic ability decreased significantly both in vitro and in vivo. Furthermore, screening of putative kinase(s) that could phosphorylate NF-κB identified that TGF-β activated kinase-1 (TAK-1) directly phosphorylated NF-κB. Staining of HCC tissue specimens showed that CD133+ liver stem cells expressed constitutively activated NF-κB.
Conclusions: Collectively, our data suggest that IL6, highly expressed in 40% HCC patients, can be considered an initiation driver to develop metastatic CSCs by constitutively activated TAK1-NFκB pathway at pre-HCC stage.
Citation Format: Abhisek Mitra, Xueqing Xia, Lopa Mishra, Shulin Li. IL6 mediated inflammatory loop reprograms normal to highly metastatic cancer stem cells at pre-HCC liver in β2SP+/- mice. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1569.
Abstract 1570: Defective collagen production by mammary epithelia leads to increased breast cancer metastasis: a novel role of vacuolar ATPase
Authors: Katara Gajendra K. , Kulshrestha Arpita , Pamarthy Sahithi , Mao Liqun , Beaman Kenneth D. 
Published: July 2016

Abstract
In cancer cells, vacuolar ATPase (V-ATPase), a multi-subunit enzyme, is expressed on the plasma as well as vesicular membranes and critically influences metastatic behavior. Recently, we have shown that by inhibiting a2 isoform of V-ATPase ‘a’ subunit (a2V) in cancer cells, in vivo tumor growth can be delayed through decreasing essential macrophage population in breast cancer. Here, we investigated whether the same tumor growth inhibition can be attain by deleting a2V in host tissue instead of cancer cell. For this purpose, we deleted a2V gene in the mouse mammary gland using MMTV-Cre lox system. Breast tumors were generated by inoculating E0771 mammary carcinoma in mammary fat pad of a2V knockout (KO) mice. We observed faster tumor growth in KO mice compared to wild type (WT). KO mice tumors showed more infiltration and metastasis of cancer cell as evident by the number of lung and liver lesions. KO mice did not display the characteristic solid tumor phenotype of breast cancer. Based on these observations, we evaluated expression and production of collagen protein which is an important component of the extra cellular matrix, in KO breast tissue. Trichrome staining showed less collagen protein in tumorous as well as in non-tumorous breast tissue of KO mice. Total collagen was measured by the hydroxyl proline assay and analysis showed that KO mice have significantly (P&lt;0.05) less amount of hydroxyl proline compared to WT mice. (16.77 ± 3.74 vs 43.67 ± 6.89). To validate our observation, we knock down a2V in HMEpC mammary epithelial cell line to measure the effect on collagen production. After a2V inhibition, the production of collagen in culture media was reduced. The data show that for an efficient tumor growth, a2V is required in both cancer cell and host tissue.
Citation Format: Gajendra K. Katara, Arpita Kulshrestha, Sahithi Pamarthy, Liqun Mao, Kenneth D. Beaman. Defective collagen production by mammary epithelia leads to increased breast cancer metastasis: a novel role of vacuolar ATPase. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1570.
Abstract 1571: PTEN is an important mediator of tumor and glia cell crosstalk in breast cancer brain metastasis
Authors: Wikman Harriet , Hohensee Ina , Chuang Han-Ning , Grottke Astrid , Werner Stefan , Schulte Alexander , Matschke Jakob , Glatzel Markus , Horn Stefan , Jücker Manfred , Pukrop Tobias , Pantel Klaus 
Published: July 2016

Abstract
With the improvement of therapeutic options for the treatment of breast cancer, the development of brain metastases has become a major limitation to life expectancy in many patients. Loss of Phosphatase and tensin homolog (PTEN) is correlated with occurrence of breast cancer brain metastases, but its functional role in metastases formation remains unclear. Here, we first assessed the clinical role of PTEN expression in brain metastases, by performing immunohistochemical analyses on a TMA consisting of 132 breast cancer brain metastases samples. Loss of PTEN protein expression was found in 48.6% of brain metastases, and significantly associated with the triple-negative breast cancer subtype (67.5%, p = 0.01). Loss of PTEN was furthermore significantly associated with shorter overall survival (p = 0.048). We then investigated the biological role of PTEN in breast cancer brain metastasis formation by overexpressing PTEN in the triple-negative brain metastatic breast cancer cell cline MDA-MB-231 BR. Overexpression of PTEN was shown to reduce the AKT pathway activation especially by reducing the Akt1 kinase activity. Coculture experiments with glia cells (astrocytes and microglia) showed that astrocytes can inhibit cell proliferation of the tumor cells in a PTEN dependent manner. Both astrocytes and microglia promote migration of MDA-MB-231 BR cells in a PTEN-dependent manner in vitro. Using an organotypic brain slice model as a representation of the brain tumor microenvironment, the PTEN-dependent invasion of tumor cells could be confirmed. Furthermore, PTEN overexpression reduced the astrocyte activation. Coculture experiments with glia cells showed PTEN-dependent, differential cytokine expression. We could identify an endocrine and paracrine regulation between tumor cells and astrocytes, where GM-CSF, CSF2RA, EGF and PTEN play an important role. In conclusion, loss of PTEN is associated with poor prognosis and is an important mediator of a “vicious circle” mediated by the cross talk between tumor cells and glia cells.
Citation Format: Harriet Wikman, Ina Hohensee, Han-Ning Chuang, Astrid Grottke, Stefan Werner, Alexander Schulte, Jakob Matschke, Markus Glatzel, Stefan Horn, Manfred Jücker, Tobias Pukrop, Klaus Pantel. PTEN is an important mediator of tumor and glia cell crosstalk in breast cancer brain metastasis. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1571.
Abstract 1572: Overexpression of Axl delays metastatic outgrowth of prostate cancer bone marrow disseminated tumor cells
Authors: Axelrod Haley D. , Valkenburg Kenneth C. , Pienta Kenneth J. 
Published: July 2016

Abstract
The presence of detectable metastases in the bone marrow of prostate cancer patients represents lethal, incurable disease. These metastases that may emerge years or decades after prostatectomy are derived from small colonies of dormant tumor cells that disseminated from the primary tumor. Our group has previously shown that Gas6/Axl signaling is associated with disseminated tumor cell (DTC) dormancy in mouse models of prostate cancer metastasis. In this study we explored the functional significance of this association and tested the hypothesis that overexpression of Axl in prostate cancer cells would prolong their dormant phase in the bone marrow. Axl overexpression in the AR-positive Axl-negative human prostate cancer cell line C42B slowed proliferation in vitro. Select cells were completely dormant as detected by the lack of EdU incorporation over 40 hours, and this fraction was increased when co-cultured with bone-forming osteoblasts. To assess the functional effects of Axl on prostate cancer progression in vivo, we utilized a mouse model of prostate cancer metastasis in which subcutaneous tumors are established and surgically removed upon reaching 200mm3. At 10 weeks post-tumor removal, mice bearing C42B-Axl tumors did not have overt osteoblastic or osteolytic lesions in their femurs or tibiae, whereas mice bearing C42B-WT tumors had visible lesions by x-ray. Immunohistochemistry staining of mouse femurs and tibiae corroborated these findings. To confirm that the absence of metastases in mice with C42B-Axl tumors was not due to the inability of the cells to disseminate, we used immunofluorescence to detect human cells in the bone marrow of flushed femurs and tibiae. At 12 weeks post-tumor removal, fewer prostate cancer cells were detected in the bone marrow of mice with C42B-Axl tumors compared to those with C42B-WT tumors. Notably however, both groups had detectable prostate cancer cells in the bone marrow, indicating that the absence of C42B-Axl metastasis was not due to failure of primary tumor cells to disseminate. The presence of disseminated C42B-Axl cells in the bone marrow coupled with their failure to develop into clinical metastases at the time of C42B-WT metastatic outgrowth establishes a functional role for the association of Axl expression with DTC dormancy. Axl may be sufficient to induce and maintain dormancy, and ongoing experiments will address the requirement of Axl in this setting.
Citation Format: Haley D. Axelrod, Kenneth C. Valkenburg, Kenneth J. Pienta. Overexpression of Axl delays metastatic outgrowth of prostate cancer bone marrow disseminated tumor cells. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1572.
Abstract 1590: N-cadherin is a key marker for epithelial-to-mesenchymal transition in clinical prostate cancer
Authors: Kolijn Kimberley , Verhoef Esther I. , van Leenders. Geert J.L.H. 
Published: July 2016

Abstract
Purpose of the study: Epithelial-to-mesenchymal transition (EMT) is characterized by E cadherin downregulation and simultaneous upregulation of mesenchymal markers such as vimentin, fibronectin and N cadherin. Studies on EMT are generally performed in cell lines and mouse models, while the histopathological and phenotypical properties in clinical prostate cancer (PCa) are still unclear. Our objective was to analyze the expression of various EMT markers in clinical PCa samples.
Experimental procedures: We performed immunofluorescent double stainings with E cadherin and the mesenchymal markers N cadherin, vimentin or fibronectin, Zeb1, Twist1, and β catenin on fresh frozen radical prostatectomies.
Summary: Immunofluorescent double stainings with E cadherin and the mesenchymal markers N cadherin, vimentin or fibronectin demonstrate that E cadherin was consistently downregulated in N cadherin positive PCa cells, but not vimentin or fibronectin positive PCa cells. Moreover, co expression of mesenchymal markers was uncommon, as PCa cells did not co express N-cadherin with fibronectin and only rarely (&lt;1%) cells with vimentin. Membranous expression of β-catenin was unaltered in N cadherin positive PCa cells, while nuclear staining could not detected. Zeb1 was expressed in the nuclei of surrounding fibroblasts, but not in PCa cells. Twist1 was localized to the nucleus of some N-cadherin negative PCa cells, but not in N-cadherin positive cells.
Conclusions: We demonstrated that N cadherin was the most reliable marker for EMT in clinical PCa as compared to vimentin and fibronectin, and that these mesenchymal markers were generally not expressed within the same cell population. The expression of N-cadherin was not associated with Twist1, Zeb1 or β-catenin expression. Despite extensive knowledge of EMT in PCa cell lines, the molecular mechanisms involved in EMT in clinical PCa is still unknown.
Citation Format: Kimberley Kolijn, Esther I. Verhoef, Geert J.L.H. van Leenders. N-cadherin is a key marker for epithelial-to-mesenchymal transition in clinical prostate cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1590.