bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 1505: Radiogenomics defines key genomic network driving GBM invasion
Authors: Colen Rivka R. , Luedi Markus , Singh Sanjay K. , Hassan Islam , Gumin Joy , Sulman Erik P. , Lang Frederick F. , Zinn Pascal O.
Published: July 2016

PURPOSE

Clinical care and outcome in Glioblastoma (GBM) remains challenging due to the tumor's invasive grwoth. To establish personalized treatment options in GBM, discovery of genetic mechanisms essential for the tumor's invasion is needed. We have previously described radiogenomic approaches to diagnose gene networks non invasively by analyzing genomic data from TCGA. The purpose of the current reseach is to identify a genetic network that drives GBM invasion and can be targeted specifically.

METHOD AND MATERIALS

Using Kaplan-Meier statistics, the data of the two independent databases TCGA and REMBRANDT were used to validate the genetic netowork's impact on clinical outcome. The genes’ staus was assessed in a panel of human glioma stem cells (GSCs) and conventional proneural, classical and mesenchymal GBM cell lines using RT-PCR. Differentiation potential (Tuj1+ve, S100A+ve, and GFAP+ve), self-renewal (limiting dilution assays), invasion (Boyden chamber) and proliferation (BrdU) were assessed. Gain (lentiviral vectors) and loss (SMARTchoice Inducible shRNA) of function experiments were performed. Orthotopic xenograft models (nude mice) were used to characterize the genes impact in vivo. Potential FDA approved therapeutics were identified using connectivity map.

RESULTS

Texture analysis based on radiogenomics significantly predicted the genes responsible for invasion of GBM in a non-invasive manner. Invasion in both, in vitro and in vivo was significantly decreased upun downregulation of this gene network. Transcriptome micro-array analysis showed that an upregulation of the described genes results in class switching from proneural to mesenchymal sub-types. Cmap derived therapeutics could significantly inhibit the gene network's activitiy and hence invasion.

CONCLUSION

The describend genes could be essential drivers of molecular subtypes and invasion in GBM. The therapeutics defined with cmap offer a targetted therapy to adress these key features of GBM pathogenesis. Noninvasive radiogenomics-based identification of tumor subgroups and potential treatment approaches can significantly contribute to personalized therapy.

CLINICAL RELEVANCE/APPLICATION

The described gene network seems to be key for GBM pathogenesis. Noninvasive, radiogenomics-based subgroup identification and specific novel treatment approaches can significanty contribution to personalized GBM therapy.

Citation Format: Rivka R. Colen, Markus Luedi, Sanjay K. Singh, Islam Hassan, Joy Gumin, Erik P. Sulman, Frederick F. Lang, Pascal O. Zinn. Radiogenomics defines key genomic network driving GBM invasion. [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 1505.
Abstract 1510: Subtype-specific cancer driver gene detection improves sensitivity to detect drivers
Authors: Fu Yao , Chhibber Aparna , Bani-Asadi Narges , Lam. Hugo YK
Published: July 2016

Identifying cancer driver mutations is a crucial step toward understanding the underlying mechanisms of oncogenesis. However, driver gene detection is complicated, considering the inherent complexity and heterogeneity of cancer.The past decade has seen the large-scale application of next-generation sequencing technologies (NGS) in cancer genomics, and many methods have been published utilizing NGS to detect novel oncogenic drivers. However, the low concordance across methods raises the concern about false positives and negatives in those findings. In particular, proper modeling of the background mutation profile (known to be affected by multiple factors) is critical to improving precision and recall in driver detection. Though intra-sample heterogeneity in the background mutation profile is considered to some extent in multiple methods, most computational driver detection methods assume a homogeneous mutational landscape across cancer samples. With more and more subtypes being discovered in various cancers, the assumption is largely untenable.

In this study, we present a driver gene detection framework taking into account the heterogeneous mutational context in a cancer cohort. Our approach improves sensitivity to detect drivers by first pre-selecting a more uniform sample subset to apply driver detection algorithms. We combine this method with enhancements to an existing ensemble approach that combines methods with different assumptions about the characteristics of driver mutations (recurrence across samples, functional impact bias and positional clustering). We apply this combined approach to ∼750 breast invasive carcinoma samples from The Cancer Genome Atlas. In this dataset, genes identified by our approach show higher enrichment in known cancer driver genes compared to other methods, and the subtype-driven method identifies additional potential drivers that are missing in overall analysis.

Citation Format: Yao Fu, Aparna Chhibber, Narges Bani-Asadi, Hugo YK Lam. Subtype-specific cancer driver gene detection improves sensitivity to detect drivers. [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 1510.
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

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

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<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<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

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

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

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

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<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

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

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

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 (<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.
Abstract 1594: Contribution of Stromal Lymphocytes to Lung Cancer Metastasis: Role in Epithelial Mesenchymal Transition
Authors: Salazar Ylia , Huber Magdalena , Schmall Anja , Seeger Werner , Pullamsetti SoniSavai , Savai Rajkumar , Huber Magdalena , Schmall Anja , Seeger Werner , Pullamsetti. SoniSavai
Published: July 2016

The tumor microenvironment and its immune components play a critical role in cancer development, progression, and control. In this study we aim to investigate the role of tumor infiltrating lymphocyte subpopulations in lung cancer progression.

Conditioned media (CM) from co-cultures of human lymphocytes with adenocarcinoma cells (A549) induced the loss of the epithelial markers (E-Cadherin and ZO2 and an increase of mesenchymal markers (vimentin, N-cadherin on mRNA and protein level. In addition, the cells demonstrated a spindled shape-like morphological changes and an increased migratory property. In order to explore the molecular mechanism that led to lymphocyte-induced EMT and migration, we performed a cytokine array from the co-culture CM and found elevated levels of IL-8, IL-16, CCL2 and G-CSF. Furthermore, we observed that lymphocyte-induced EMT was mediated via a TGFβ-independent pathway that involves phosphorylation of ERK1/2.

Notably, this EMT phenotype induction by lymphocytes was independent of the pre-activation of lymphocytes with PMA. Furthermore, in order to identify the specific CD4+ T cell subpopulations (Th0, Th1, Th9 and Th17) responsible for the EMT effect, we generated specific subpopulations from mouse spleen T cells. Interestingly, we observed that Th9 and Th17 subpopulation CM led to EMT and increased migratory phenotype in mouse lung cancer cell lines. Additionally, we identified the T lymphocyte secretory cytokine, IL9, as responsible for the Th9 induced EMT and migratory phenotype of lung cancer cells.

This study reveals that specific T lymphocyte subpopulations, i.e. Th9 and Th17 induce EMT in lung cancer cells, suggesting T cell regulated mechanisms of metastasis.

Citation Format: Ylia Salazar, Magdalena Huber, Anja Schmall, Werner Seeger, SoniSavai Pullamsetti, Rajkumar Savai, Magdalena Huber, Anja Schmall, Werner Seeger, SoniSavai Pullamsetti. Contribution of Stromal Lymphocytes to Lung Cancer Metastasis: Role in Epithelial Mesenchymal Transition. [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 1594.
Abstract 1597: Claudin-1 expression promote TNF-a-induced epithelial-mesenchymal transition and growth in colorectal adenocarcinoma cells
Authors: Bhat Ajaz Ahmad , Ahmad Rizwan , Singh Amar B. , Dhawan Punita
Published: July 2016

Epithelial-mesenchymal transition (EMT) is an important mechanism in colorectal cancer progression and malignancy. Importantly, inflammatory mediators are critical constituents of the local tumor environment and an intimate link between colon cancer progression and inflammation in now validated. Notably, we and others have previously reported key role of the deregulated claudin-1, a tight junction protein, in colon carcinogenesis including colitis-associated colon cancer (CAC). Of interest, the increase in claudin-1 expression in CAC was found to be associated with the inflammatory epithelium. We have further demonstrated that inflammation induced by DSS (Dextran Sodium Sulfate) administration promotes colon cancer in APCmin/Claudin-1 transgenic mice. However, what role claudin-1 plays in inflammation-induced colon cancer remains unclear. In current study, we tested the causal significance of claudin-1 expression in inflammation-associated colon cancer using colon cancer cells subjected to TNF-αα, a pro-inflammatory cytokine, treatment. HT29 colon adenocarcinoma cells cultured in the presence of TNF-α (10ng/ml), demonstrated a sharp decrease in E-cadherin expression and an increase in Vimentin expression versus control cells suggesting TNF-αα treatment induced EMT. Also, significant increase in cell proliferation and wound healing was observed in TNF-α treated cells at 24 and 48 hours of TNF-αα treatment (versus control cells). Interestingly, TNF-αα treatment also upregulated (and delocalized) claudin-1 expression in a time-dependent manner. An increase in the phosphorylation of Erk1/2 and Src, signaling associated with colon cancer survival and transformation, in TNF-αα treated cells further correlated with our published observations that claudin-1 expression promotes these signaling pathways in colon cancer cells. In support, shRNA-mediated inhibition of claudin-1 expression in HT-29 cells largely abrogated the effects of TNF-αα treatment including proliferation, p-erk and p-Src expression. Also, TNF-αα induced EMT was largely suppressed in the absence of claudin-1 expression. Taken together, our data confirm the previously described key role of claudin-1 in regulating tumorigenic abilities of colon cancer cells and further highlights a key role of claudin-1 in inflammation-induced colorectal cancer growth and progression. We predict claudin-1 expression can serve as a biomarker to predict CAC progression and malignancy.

Citation Format: Ajaz Ahmad Bhat, Rizwan Ahmad, Amar B. Singh, Punita Dhawan. Claudin-1 expression promote TNF-a-induced epithelial-mesenchymal transition and growth in colorectal adenocarcinoma 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 1597.
Abstract 1608: Resistin promotes cancer progression through induction of mesenchymal phenotypes and stem cell-like properties in breast cancer
Authors: Yuan Shyng-Shiou F. , Wang Chie-Hong
Published: July 2016

Growing evidence indicates that resistin plays a role in insulin resistance, obesity, inflammation, coronary artery disease, atherosclerosis and malignancies. In this study, we have explored the effects and mechanisms of resistin in promoting breast cancer progression. High serum resistin levels were positively correlated with tumor stage, tumor size and lymph node metastasis in breast cancer patients. Resistin treatment modulated the expression of epithelial-mesenchymal transition (EMT) regulators and enhanced the migratory, invasive and anti-anoikis activities in breast cancer cells. Additionally, resistin treatment promoted the formation of mammospheres and the expression of pluripotency factors (sox2, nanog and oct4). STAT3 specific inhibitor, stattic, was able to abolish the resistin mediated enhancements of cell motilities and stem cell-like properties. Using in vivo model, we found that resistin markedly enhance metastasis and tumor growth. Taken together, our data clearly demonstrated that resistin promotes cancer progression through induction of EMT and stemness by activating TLR4/STAT3 signaling in breast cancer.

Citation Format: Shyng-Shiou F. Yuan, Chie-Hong Wang. Resistin promotes cancer progression through induction of mesenchymal phenotypes and stem cell-like properties in 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 1608.
Abstract 1614: Identification of FBXL4 as a bone metastasis-associated gene in prostate cancer
Authors: Stankiewicz Elzbieta , Mao Xueying , Mangham D Chas , Xu Lei , Fisher Gabrielle , North Bernard , Moller Henrik , Scardino Peter , Cuzick Jack , Berney Dan , Lu Yong-Jie
Published: July 2016

Prostate cancer (PCa) is the most common cancer among men in Western developed countries. While the majority of PCa diagnosed by PSA screening are indolent, advanced and metastatic disease has a significant mortality and morbidity. Bone metastases are extremely common in PCa and identification of bone metastasis associated genes may provide insights into PCa progression and assist in finding new drug targets. However, the genetic study of bone metastases is very limited due to the difficulty of sampling. By analyzing PCa bone metastases using high density microarrays, we found a common genomic copy number loss at 6q16.1-16.2, containing the FBXL4 gene, which was confirmed in a separate and larger series of bone metastatic samples by fluorescence in situ hybridization (FISH). Loss of FBXL4 was also detected in primary PCa, although at a significantly lower frequency than in bone metastases, and it was highly associated with prognostic factors including high Gleason score, clinical stage, PSA and extent of disease, as well as poor patient survival in conservatively-managed localized PCa, suggesting that loss of FBXL4 contributes to PCa progression. We also demonstrated that FBXL4 deletion is detectable in circulating tumor cells, making it a potential disease prognostic or progression monitoring biomarker by ‘liquid biopsy’. Consistent with loss of FBXL4 being associated with aggressive tumors, we demonstrated in vitro that FBXL4 plays a role in regulating the migration and invasion of PCa cells. Therefore, FBXL4 is a potential novel PCa suppressor gene, which may prevent cancer progression and bone metastasis through controlling cell invasion.

Citation Format: Elzbieta Stankiewicz, Xueying Mao, D Chas Mangham, Lei Xu, Gabrielle Fisher, Bernard North, Henrik Moller, Peter Scardino, Jack Cuzick, Dan Berney, Yong-Jie Lu. Identification of FBXL4 as a bone metastasis-associated gene 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 1614.
Abstract 1615: Metastasis suppression by KP54 and non-KP54 kisspeptins
Authors: Hampton Kelsey R. , Pounds Keke M. , Trembath Andrew P. , Welch Danny R.
Published: July 2016

The KISS1 metastasis suppressor blocks metastasis by inhibiting colonization at secondary sites. In order to suppress metastasis, KISS1 must be secreted and cleaved by furin into kisspeptins. Kisspeptin-54 (KP54, K67 to F121) binds a G-protein coupled receptor, KISS1R, and the mechanism of metastasis suppression has been assumed to be through KP54 binding with KISS1R. However, since KISS1 is cleaved extracellularly, and since none of the cells tested express KISS1R, an alternate hypothesis is required - another kisspeptin is responsible for suppressing metastasis. To test this hypothesis, we engineered all ten of the possible kisspeptins based upon predicted dibasic cleavage sites (M1-Q145; M1-R56; M1-R67; M1-R124; R56-R66; R67-F121; R56-F121; R56-Q145; R67-Q145; R124-Q145). The (KISS1 Manufactured Peptides, or KMP) each contained the same secretion signal as nascent KISS1 and were designated KMP1 to KMP10 respectively. Each KMP was expressed individually in B16-F10 melanoma cells. Following intravenous injection, experimental lung metastases were quantified. While KP54 expression suppressed metastasis, other KMP lacking the KISS1R binding motif also suppressed metastasis as or more effectively (p<0.05). In vitro, cell lines expressing suppressor KMP inhibited motility, increased mitochondrial biomass, and elevated levels of oxidative phosphorylation (phenotypes previously correlated with KISS1 function). In particular, KMP2 (M1 - R56) completely suppressed metastasis. Collectively, these data demonstrate that the mechanism of action for metastasis suppression by KISS1 does not necessarily require activation of KISS1R, and also suggests the existence of additional receptors.

Support: CA134981, Natl Fndn Cancer Res, Komen SAC11037, KS Bioscience Auth, P30-CA168524, Steiner Family Fund for Metastasis Research.

Citation Format: Kelsey R. Hampton, Keke M. Pounds, Andrew P. Trembath, Danny R. Welch. Metastasis suppression by KP54 and non-KP54 kisspeptins. [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 1615.
Abstract 1625: CUB domain-containing protein 1 (CDCP1) promotes metastatic phenotype in pancreatic ductal adenocarcinoma
Authors: Kim Sunnie , Emerling Brooke , Hopkins Benjamin , Loughran Ryan , Naranjos Salva , Cantley Lewis
Published: July 2016

CUB domain-containing protein 1 (CDCP1) is a transmembrane glycoprotein that is overexpressed and highly tyrosine phosphorylated in multiple cancer types including pancreatic ductal adenocarcinoma (PDAC), a highly lethal disease. CDCP1 has been implicated in the promotion of metastases, namely cancer cell migration, invasion, and resistance to anoikis. In addition, prior studies in other cancer cell lines have shown that hypoxia inducible factors (HIF-1α and HIF-2α), which are key regulators of metastasis, induce both expression of CDCP1 and phosphorylation at tyrosine 734. The role of CDCP1 and the mechanisms that regulate CDCP1 still need further elucidation in PDAC.

In this study, we demonstrated that CDCP1 is highly expressed and tyrosine phosphorylated in PDAC cell lines MiaPaCa2, PaTu89902, and Panc-1 cell lines compared to the non-tumorigenic pancreatic ductal cell line HPNE. shRNA knockdown of CDCP1 showed a reduction in the phosphorylation of Src and PKC-delta. To determine whether HIF regulates CDCP1 in PDAC, we used PDAC cell lines that stably express shRNAs targeting HIF-1α and HIF-2α. Hypoxia induced an increase in CDCP1 expression in a HIF-1α-dependent fashion. Additionally, CDCP1 knockdown in PaTu8902, a highly metastatic PDAC line, impaired cancer cell invasion by transwell invasion assay but did not show resistance to anoikis by soft agar assay. To validate our data in vivo, we performed intra-pancreatic injection of shCDCP1 PaTu8902 cells and scramble control transfected with GFP/luciferase into nude mice. Live imaging demonstrated that 2 weeks after initial injection resulted in decreased tumor establishment in mice injected with the shCDCP1 cell line compared to control. We propose that CDCP1 expression and tyrosine phosphorylation in PDAC is mediated by hypoxia inducible factors and that CDCP1 confers invasive properties in vitro and may play a role in initial tumor establishment in vivo. Based on these results, CDCP1 is a promising novel target for PDAC.

Citation Format: Sunnie Kim, Brooke Emerling, Benjamin Hopkins, Ryan Loughran, Salva Naranjos, Lewis Cantley. CUB domain-containing protein 1 (CDCP1) promotes metastatic phenotype in pancreatic ductal adenocarcinoma. [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 1625.
Abstract 1639: CDCP1 cleavage is necessary for homodimerization-induced migration of triple-negative breast cancer
Authors: Wright Heather , Arulmoli Janahan , Motazedi Maryam , Nelson Luke , Razorenova Olga
Published: July 2016

Triple negative breast cancer (TNBC) is a highly aggressive and metastatic form of breast cancer that lacks the estrogen, progesterone, and HER2 receptors and is resistant to targeted and hormone therapies. TNBCs express high levels of the transmembrane glycoprotein, CUB-domain containing protein 1 (CDCP1), which has been correlated with the aggressiveness and poor prognosis of multiple carcinomas. Full-length CDCP1 (flCDCP1) can be proteolytically cleaved, resulting in a cleaved membrane-bound isoform (cCDCP1). CDCP1 is phosphorylated by Src family kinases in its full-length and cleaved states, which is important for its pro-metastatic signaling. We observed that cCDCP1, compared to flCDCP1, induced a dramatic increase in phosphorylation of the migration-associated proteins: PKCδ, ERK1/2, and p38 MAPK in HEK 293T. In addition, only cCDCP1 induced migration of HEK 293T cells and rescued migration of the TNBC cell line, MDA-MB-231, expressing shRNA against CDCP1. Importantly, we found that only cCDCP1 is capable of dimerization, which can be blocked by expression of the extracellular portion of cCDCP1 (ECC), indicating that dimerization occurs through CDCP1's ectodomain. We found that ECC inhibited phosphorylation of PKCδ and migration of TNBC cells in 2D culture. Furthermore, ECC induced morphological changes, inhibited proliferation, and stimulated apoptosis of TNBC cells in 3D culture, indicating that the cCDCP1 dimer is an important contributor to TNBC aggressiveness. These studies have important implications for development of a therapeutic to block CDCP1 activity and TNBC metastasis.

Citation Format: Heather Wright, Janahan Arulmoli, Maryam Motazedi, Luke Nelson, Olga Razorenova. CDCP1 cleavage is necessary for homodimerization-induced migration of triple-negative 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 1639.
Abstract 1640: SORBS1-related multiprotein complex regulates metastasis of cancer
Authors: Cho Woo-Cheol , Ku Ja-Lok
Published: July 2016

Purpose: CAP (Cbl-associated protein), also known as Sorbin and SH3 domain-containing protein 1 is encoded by the SORBS1 gene. These proteins contain a conserved sorbin homology (SOHO) domain and three SH3 domains. CAP is an adaptor protein that has been associated with the actin cytoskeleton, signaling through receptor tyrosine kinases and cell adhesion. Although, CAP is proven to have many known functions, this protein is only reported in specific field of signaling pathway. Cell adhesion and actin dynamics which have been supposed to participate in CAP are crucial factors of cancer metastasis. The role of CAP has been described in the literature, although their specific roles remain to be clarified in cancer.

Methods and materials: Colorectal cancer cell lines were transduced by lentivirus containing shRNA plasmid (shSORBS1 plasmid). To elucidate function of SORBS1 as regulator of cancer metastasis, western blotting, cell migration assay and immunoprecipitation assays were performed.

Conclusion: According to the several reports of SORBS1 function, phosphorylation of ERK and mTOR was identified. Although ERK phosphorylation were not changed in normal condition, there were different aspects between control group and SORBS1 knockdown group with insulin treatment. Moreover, mTOR phosphorylation of SORBS1 knockdown group was less in the control group than in the normal condition.

Immunoprecipitation of SORBS1 was performed to search for the binding compounds. We chose the AHNAK protein as the convincing candidate protein related with SORBS1. Several studies reported that AHNAK protein is related to proliferation and EMT by binding of specific signaling molecules. Indeed, there were remarkable differences of invasiveness ability between control group and knockdown group.

Citation Format: Woo-Cheol Cho, Ja-Lok Ku. SORBS1-related multiprotein complex regulates metastasis of 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 1640.