bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 5150: Drosophila models of Ret fusions in papillary thyroid carcinoma
Authors: Levinson Sarah , Cagan Ross
Published: August 2015

Ret fusion proteins, including PTC1 (CCDC6-RET) and PTC3 (NcoA4-RET), drive a subset of Papillary Thyroid Carcinomas (PTC). There is currently no treatment for refractory, metastatic PTC, which results in 1500 deaths in the US each year. A challenge in identifying targeted therapies for Ret fusion driven cancers has been the lack of predictive models. We created transgenic, over-expression Drosophila models of PTC1 and PTC3, and found that they cause cancer phenotypes such as delamination, cell migration, and EMT. We conducted a genetic screen of the Drosophila kinome (252 alleles) and a drug screen of FDA approved cancer therapeutics (62 compounds) against flies expressing either PTC1 or PTC3. We found that PTC1 and PTC3, despite containing identical Ret kinase domains, have a different signaling output and are sensitive to different kinase inhibitors. Of the 19 kinases that were identified as hits from the PTC3 kinome screen, only 5 overlap with PTC1 hits. PTC3 is most sensitive to Ponatinib, where as PTC1 is most sensitive to Cabozantinib. These findings suggest that patients may greatly benefit from targeted treatment directed against the specific Ret fusion that they harbor.

Citation Format: Sarah Levinson, Ross Cagan. Drosophila models of Ret fusions in papillary thyroid carcinoma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5150. doi:10.1158/1538-7445.AM2015-5150
Abstract 5166: THE WNT SIGNALING PATHWAY IN THE OVARIAN CARCINOMA
Authors: chehover michal , Tropé Claes , Reich Reuven , Davidson Ben
Published: August 2015

Ovarian carcinoma is the most lethal gynecological cancer and currently ranks as the fifth in causing cancer-related deaths among women. This is attributed to frequent presentation at late stage, when the tumor has metastasized, as well as to development of chemotherapy resistance along tumor progression. Patients with advanced-stage ovarian carcinoma have widespread intraperitoneal metastases, including the formation of malignant serous effusions within the peritoneal cavity. Unlike the majority of solid tumors, particularly at the primary site, cancer cells in effusions are not amenable to surgical removal, and failure in their eradication is one of the main causes of treatment failure.

Three WNT signaling pathways have been characterized: the canonical WNT pathway, the non-canonical planar cell polarity pathway, and the non-canonical WNT/calcium pathway. All three WNT signaling pathways are activated by the binding of a WNT-protein ligand to a Frizzled family receptor, which passes the biological signal inside the cell. Several lines of research indicate on the involvement of these pathways also in ovarian carcinomas. However, the specific pathway or their regulation in the process of tumor progression in this disease has not been elucidated, so far.

The aim of the current study is to identify the acting components of these pathways during tumor progression namely, which receptors and which ligands are activated at the different stages of ovarian carcinoma. We have analyzed the expression 7 frizzle genes (fzd1, 2, 4, 5, 6, 7, 8, 10), 4 WNT genes (wnt 2,3,4,5a,7) and 2 co-receptors LRP (5,6) on 222 samples (143 effusions, 44 primary, and 35 metastatic lesions) using real-time PCR. All the tested genes were found to be expressed at all sites. FRZ5 (p = 0.002), FRZ6 (p<0.001), Wnt2 (p = 0.029), Wnt3 (p = 0.034) and Wnt6 (p = 0.022) were lower in effusion-derived cells compared to solids lesions. Further, Wnt2 expression was higher in pre-chemo (p = 0.037) samples compared to post-chemo ones. FRZ6 expression was higher in FIGO stage IV compared to stage III of the disease (p = 0.041), and FRZ4 expression was higher in cases with lower residual disease volume (p = 0.002). Wnt5a was higher in patients with better (complete) response (p = 0.019). FRZ6 expression was associated with poor overall survival (p = 0.045) and progression-free survival (p = 0.009). FRZ10 expression was associated with better overall survival (p = 0.005) and progression-free survival (p = 0.005).

Citation Format: michal chehover, Claes Tropé, Reuven Reich, Ben Davidson. THE WNT SIGNALING PATHWAY IN THE OVARIAN CARCINOMA. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5166. doi:10.1158/1538-7445.AM2015-5166
Abstract 5172: Developing a lung metastasis gene signature using a lung tropism model in melanoma
Authors: Wen Yu , Shan Maung Naing Lin , Li Jiadong , Goydos James
Published: August 2015

A patient with metastatic melanoma has a 5-year survival rate of only 15%. As with most cancers, approximately 90% of fatalities are caused by metastatic spread of tumor cells to vital organs like the liver, lung, brain, bone, etc. Lung is one of the leading metastatic sites of melanoma at initial presentation, yet the mechanisms that lead to melanoma lung metastases are not well understood. For our study we have developed an in vivo ‘spontaneous lung-metastasis model’ using two human melanoma cell lines, UACC903 and C8161, with different genetic backgrounds. Parental melanoma cells were injected subcutaneously into nude mice. After the tumors reached the maximum allowable size of 1.5 cm, survival surgery was performed to remove the subcutaneous tumors and the animals were observed for an additional 4 weeks or until the animals appeared ill. The animals were sacrificed and lung metastases were surgically removed and re-cultured. The two new cell lines were designated as UACC903-LM and C8161-LM. This process was repeated using these new cell lines to obtain a second round of lung metastasizing lines we designated as UACC903-LMM and C8161-LMM. Using the parental and metastasizing cell lines we have been able to identify a lung metastasis gene signature using PCR array analysis, validated by PCR and Western Blot. This lung metastasis gene signature was further supported by the identification of increased expression of the same set of genes in lung metastasis as compared to primary tumors from patients with melanoma. We have also observed increased migration in metastasizing cell lines as compared to the parental lines using a trans-well migration assay with fetal bovine serum as chemo-attractant. CXCR-4 was one of gene products up-regulated in the metastasizing cell lines and the FDA-approved CXCR-4 antagonist, AMD-3100, inhibited trans-well migration of the metastasizing cell lines far more than parental cell lines. Our ongoing studies are examining the potential of inhibiting CXCR-4, and other gene products from our metastasis gene signature, as a therapeutic option in patients with advanced melanoma.

Funding: NIH RO1-563057

Note: This abstract was not presented at the meeting.

Citation Format: Yu Wen, Maung Naing Lin Shan, Jiadong Li, James Goydos. Developing a lung metastasis gene signature using a lung tropism model in melanoma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5172. doi:10.1158/1538-7445.AM2015-5172
Abstract 5179: An endothelial-mesenchymal transition of brain endothelial cells is required for metastatic extravasation
Authors: Krizbai Istvan A. , Gasparics Akos , Nagyoszi Peter , Fazakas Csilla , Wilhelm Imola , Bencs Rita , Rosivall Laszlo , Sebe Attila
Published: August 2015

Endothelial-mesenchymal transition (EndMT) is an embryonic program necessary for organ development. Despite being normally dormant in adult organisms, this mechanism can be reactivated during several pathological conditions, such as cancer and fibrosis. EndMT is characterized by the downregulation of the endothelial program, activation of the mesenchymal-fibrogenic program, and finally the activation of the myogenic program. Cancer progression towards metastasis follows a defined sequence of events described as the metastatic cascade. For extravasation and transendothelial migration metastatic cells interact first with endothelial cells. Yet the role of endothelial cells during the process of metastasis formation and extravasation is still unclear, and the interaction between metastatic and endothelial cells during transendothelial migration is poorly understood. Since tumor cells are well known to express TGF-β, and the compact endothelial layer undergoes a series of changes during metastatic extravasation (cell contact disruption, cytoskeletal reorganization, contractility), we hypothesized that an EndMT may be necessary for metastatic extravasation.

We show that primary rat brain endothelial cells (BECs) undergo EndMT upon TGF-β1 treatment, characterized by the loss of tight and adherent junction proteins, the expression of fibronectin, β1-integrin, calponin and α-smooth muscle actin (SMA), and an increase in N-cadherin levels. B16/F10 activated conditioned medium (ACM) induced claudin-5 downregulation, fibronectin and SMA expression in BECs. Inhibition of TGF-β signaling during B16/F10 ACM stimulation using SB-431542 maintained claudin-5 levels and mitigated fibronectin and SMA expression. SB-431542 prevented SMA upregulation upon stimulation of BECs with A2058, MCF-7 and MDA-MB231 ACM. Moreover, B16/F10 ACM caused a reduction in transdendothelial electrical resistance and enhanced the number of melanoma cells adhering to the endothelial layer, both in a TGF- β dependent manner. Finally, pretreatment with TGF-β1 or B16/F10 ACM enhanced transendothelial migration of B16/F10 cells.

Our results indicate that an EndMT may be necessary for metastatic transendothelial migration, and may play a relevant role during the complex phenomenon known as metastatic extravasation.

Citation Format: Istvan A. Krizbai, Akos Gasparics, Peter Nagyoszi, Csilla Fazakas, Imola Wilhelm, Rita Bencs, Laszlo Rosivall, Attila Sebe. An endothelial-mesenchymal transition of brain endothelial cells is required for metastatic extravasation. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5179. doi:10.1158/1538-7445.AM2015-5179
Abstract 5183: Identification and characterization of wild type kinases driving prostate cancer metastasis
Authors: Faltermeier Claire , Drake Justin , Clark Peter , Smith Bryan , Mathis Colleen , Zong Yang , Volpe Carmen , Witte Owen
Published: August 2015

Despite numerous oncogenic alterations implicated in metastatic prostate cancer, mutations or DNA amplifications of kinases are rare. We previously demonstrated that 1) expression of wild type (wt) Src in combination with the androgen receptor synergizes to produce aggressive prostate adenocarcinoma, 2) tyrosine phosphorylation increases with prostate cancer stage, and 3) the phosphoproteomic profile of metastatic prostate cancer is different from localized disease. However, the question still remains as to whether wt kinases can drive prostate cancer metastasis and should be regarded as therapeutic targets. To identify wt kinases driving prostate cancer metastasis, we performed phospho-tyrosine, threonine and serine peptide enrichment and quantitative mass spectrometry on metastatic prostate cancer tissues obtained at rapid autopsy. Analysis of this phosphoproteomic dataset combined with bioinformatic analyses of genomic datasets identified ∼140 kinases differentially expressed or activated in prostate cancer metastases. To determine which of these kinases function to promote prostate cancer metastasis, we developed an in vitro and in vivo metastasis screen. Out of 140 kinases, 20 kinases promote resistance to anoikis in vitro and metastatic colonization in vivo. Positive kinases include Src, Lyn, and EGFR which have been previously reported to be important in prostate cancer metastasis and thus provide strength to the validity of our screen. In addition we identified kinases with uncharacterized roles in prostate cancer metastasis and of particular interest, several of these kinases promote bone metastasis. We expect our findings will improve our understanding of the mechanistic role of kinase activation in prostate cancer and identify promising new therapeutic targets for metastatic disease.

Citation Format: Claire Faltermeier, Justin Drake, Peter Clark, Bryan Smith, Colleen Mathis, Yang Zong, Carmen Volpe, Owen Witte. Identification and characterization of wild type kinases driving prostate cancer metastasis. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5183. doi:10.1158/1538-7445.AM2015-5183
Abstract 5189: Inhibitory effect of phytochemicals on oncostatin-M-induced tumor invasion and migration in human esophageal carcinoma
Authors: Naka Eijin , Takahashi Yuko , Matsubara Hisahiro , Kato Kazunori
Published: August 2015

An epithelial-to-mesenchymal transition (EMT) is one of important phenomenon in tumor metastasis. Oncostatin-M (OSM) belonging to the IL-6 family is a cytokine that participates in invasion and migration of various cancer cells. It is produced by macrophage and stimulates the JAK/STAT signal transduction pathway. In this study, we examined the effect of OSM on EMT of human esophageal carcinoma cells and found a way to inhibit cell metastasis. We first observed morphological changes of tumor cells from an epithelial-like phenotype to a more spindle-shaped, mesenchymal phenotype by OSM. Consistent with these findings, OSM also promoted cell motility using a wound scratch assay and matrigel invasion assay. Moreover, we observed that intracellular stat3 phosphorylation was promoted by the stimulation of OSM by Western blotting. To confirm the contribution of p-stat3, we used a selective JAK2/STAT3 inhibitor cucurbitacin I. As a result, cucurbitacin I strongly inhibited OSM-induced tumor cell invasion and migration. Then, we used two dietary phytochemical resveratrol (polyphenol in grapes) and sulforaphane (isothiocyanate in broccolis), both were reported as candidates of stat3 inhibitor. By the addition of resveratrol or sulforaphane, we found that these markedly inhibited OSM-induced stat3 phosphorylation, the expression of EMT-related genes (snail, slug and vimentin) and tumor cell migration. Overall, our findings provide new evidence that these phytochemicals suppress OSM-induced tumor invasion and migration through inhibiting stat3 phosphorylation and EMT pathway.

Citation Format: Eijin Naka, Yuko Takahashi, Hisahiro Matsubara, Kazunori Kato. Inhibitory effect of phytochemicals on oncostatin-M-induced tumor invasion and migration in human esophageal carcinoma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5189. doi:10.1158/1538-7445.AM2015-5189
Abstract 5190: CCR6-mediated molecular mechanisms involved in colon cancer
Authors: Kapur Neeraj , Mir Hina , Singh Rajesh , Singh Shailesh
Published: August 2015

Colon cancer is one of the leading causes of death due to cancer worldwide. Molecular mechanism of initiation and progression of this disease is yet to be defined. Chemokines and their corresponding receptors have been shown to play important role in progression of many cancers including colon. In this study we have demonstrated that CCR6 is highly expressed in colon cancer and is associated with key steps of metastasis. Cell migration, adhesion and invasion are the key features of cancer progression. This process initiates with the change of less motile epithelial phenotype to a more motile mesenchymal type, the phenomenon known as epithelial-mesenchymal transition (EMT). Interestingly, stimulation of colon cancer cell with CCL20, which is the only natural ligand for CCR6, showed significant decrease in E-cadherin. Furthermore, increased Vimentin, beta-Catenin, N-cadherin, alpha-Smooth Muscle Actin (αSMA) and Snail following CCL20 treatment implicates potential role of CCR6-CCL20 axis in transition to mesenchymal phenotype. Hence, strategies directed to this chemokine-receptor axis may improve therapeutic outcome of colon cancer.

Citation Format: Neeraj Kapur, Hina Mir, Rajesh Singh, Shailesh Singh. CCR6-mediated molecular mechanisms involved in colon cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5190. doi:10.1158/1538-7445.AM2015-5190
Abstract 5191: Missense mutants of p53 tumor suppressor contributes to drug-resistance and epithelial-mesenchymal transition in colon cancer cells
Authors: Hosain Salman B. , Liu Yong Y.
Published: August 2015

The mutants of p53 tumor suppressor that have been detected in approximately 50% of tumors exhibit oncogenic function and promote tumor progression. Restoration of tumor suppression by introduction of wild-type p53 effectively eliminate cancers in preclinical studies; however, more than 80% of p53 mutations are missense mutants, those can form heterotetramers and diminish the therapeutic effect of p53 transgene. It is still unclear how missense mutants promote tumor progression, particularly in whether or not these mutants contribute to induced cancer stem cells during chemotherapy. We report herewith that R273 missense mutant contributes to drug-induced stem cell-like behavior in colorectal cancer cells. Heterozygous SW48 TP53 (R273H/+) cells presented the same sensitivity to doxorubicin and paclitaxel as its parental SW48 colon cancer cells. However, after exposure to lower concentrations of doxorubicin (10 nM) or paclitaxel (4 nM) for eight weeks, SW48 TP53 not only were resistant to anticancer drugs, but also displayed an epithelial-mesenchymal transition (EMT). With the overexpressed E-cadherin and down-expressed vimentin, SW48 TP53 cells that were exposed to doxorubicin displayed significantly EMT morphological changes and increased wound healing, compared to SW 48 cells. Interestingly, inhibition of ceramide glycosylation with PDMP to increase endogenous ceramide restored wild-type p53 expression in heterozygous SW48 TP53 cells exposed to doxorubicin and further sensitized these cells to anticancer drugs and reversed EMT. These findings indicate that a heterozygous missense p53 mutant promotes EMT and drug resistance of colon cancer cells in chemotherapy, and restoration of p53 expression with suppression ceramide glycosylation can improve therapeutic efficacy.

Citation Format: Salman B. Hosain, Yong Y. Liu. Missense mutants of p53 tumor suppressor contributes to drug-resistance and epithelial-mesenchymal transition in colon cancer cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5191. doi:10.1158/1538-7445.AM2015-5191
Abstract 5193: Ataxia telangiectasia mutated relates to epithelial-mesenchymal transition in colorectal cancer
Authors: Takahashi Hidena , Tsuruta Masashi , Hasegawa Hirotoshi , Okabayashi Koji , Seishima Ryo , Matsui Shimpei , Yamada Toru , Kondo Takayuki , Shimada Takehiro , Matsuda Mutsuhito , Yahagi Masashi , Yoshikawa Yusuke , Asada Yusuke , Sugiura Kiyoaki , Suzuki Yoshiyuki , Tajima Yuki , Nakadai Junpei , Kitagawa Yuko
Published: August 2015

Background: The Ataxia telangiectasia mutated (ATM) is a serine/threonine protein kinase that is recruited and activated by DNA double-strand breaks. Recently, ATM was reported to correlate with breast cancer metastasis by regulating phosphorylated Snail which was known as a marker of epithelial-mesenchymal transition (EMT), however, it remains unclear in colorectal cancer (CRC). In this study we attempted to clarify the impact of ATM on the mechanism of EMT in CRC.

Methods: Potential ATM levels were evaluated in human CRC cells (HT29 and SW480) by qPCR and western blot analysis. Cells were induced EMT by treated with TGF-b, were confirmed by the change of EMT markers (i.e. N-cadherin, E-cadherin, Snail and twist). Next, ATM levels were down-regulated by siRNA and the impact on EMT were evaluated by EMT markers. Invasive potential was evaluated by scratch assay.

Results: HT29 showed significantly higher levels of ATM comparing to SW480 (p = 0.042). N-cadherin (p = 0.065), Snail (p = 0.034) and twist (p = 0.052) were highly observed in HT-29, while similar level of E-cadherin in SW480 (p = 0.692). Scratch assay revealed that approximately 4 times high migration was observed in HT29. TGF-b induced EMT such as elevation of N-cadherin and Snail (E-cadherin was not affected), leading to promotion of cell migration in SW480. ATM was successfully 48.4% down-regulated (p = 0.001) in SW480, which resulted in reducing cell migration (p = 0.033).

Conclusions: ATM might be a critical regulator of EMT in colorectal cancer invasion.

Citation Format: Hidena Takahashi, Masashi Tsuruta, Hirotoshi Hasegawa, Koji Okabayashi, Ryo Seishima, Shimpei Matsui, Toru Yamada, Takayuki Kondo, Takehiro Shimada, Mutsuhito Matsuda, Masashi Yahagi, Yusuke Yoshikawa, Yusuke Asada, Kiyoaki Sugiura, Yoshiyuki Suzuki, Yuki Tajima, Junpei Nakadai, Yuko Kitagawa. Ataxia telangiectasia mutated relates to epithelial-mesenchymal transition in colorectal cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5193. doi:10.1158/1538-7445.AM2015-5193
Abstract 5197: Claudin-1 enhances tumor proliferation and metastasis by regulating cell anoikisin gastric cancer
Authors: Li Jiangfang , Huang Jie , Liu Bingya , Zhu Zhenggang
Published: August 2015

Claudin-1 (CLDN1) is overexpressed in gastric cancer and correlated with tumor invasion, metastasis and poor outcome. Here, we both down and up regulated CLDN1 expression in gastric cancer cells to elucidate its role in gastric carcinogenesis and tumor progression. As results, we found that deficiency of CLDN1 inhibited cells migration, invasion, and colony formation in vitro and tumorigenicity, metastasis in vivo. Furthermore, CLDN1 expression promoted cell aggregation and increased anoikis resistance. Down or up regulated CLDN1 were accompanied with variations of membrane β-catenin expression and activities of Akt and Src signals. When β-catenin was up-regulated in CLDN1-KD cell, cell aggregation and anoikis resistance were restored, and Akt and Src signal pathways were re-activated. Taken together, these findings suggested that CLDN1 may function as an oncogene in gastric cancer and its malignant potential may attribute to the regulation of cell anoikis through mediating membrane β-catenin regulated cell-cell adhesion and survival signals of Akt and Src.

Note: This abstract was not presented at the meeting.

Citation Format: Jiangfang Li, Jie Huang, Bingya Liu, Zhenggang Zhu. Claudin-1 enhances tumor proliferation and metastasis by regulating cell anoikisin gastric cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5197. doi:10.1158/1538-7445.AM2015-5197
Abstract 520: MIEN1 drives breast cancer invasion by regulating cytoskeletal dynamics
Authors: Kpetemey Marilyne , Vishwanatha Jamboor
Published: August 2015

Introduction: The emergence of metastases remains the primary cause of cancer mortality and morbidity. Active migration of tumour cells is a prerequisite for tumor-cell invasion and metastasis. We identified Migration and Invasion Enhancer 1(MIEN1) as a novel promoter of cell migration/invasion.

Previously known as C35, C17orf37, RDX12 and MGC14832, MIEN1 is a novel gene located in the chromosomal region 17q12-21. While absent or low in normal tissues, MIEN1 is abundantly expressed in multiple cancers including breast carcinomas. A membrane-bound signaling adaptor, MIEN1 localizes to the leading edge of migrating cells and promotes migration and invasion by increasing filopodium formation. While MIEN1 is shown to promote motility through filopodia formation, little is known on the mechanisms by which MIEN1 influence the actin cytoskeleton. Exploring underlying mechanisms, we show that MIEN1 associates with the actin cytokeleton during motility and directly influence actin polymerization.

Methods: We performed immunofluorescence, migration and invasion assays using breast cancer cell lines, MDA-MB 231 and MCF10CA1a to investigate the mechanisms by which MIEN1 potentiates cell motility.

Results: Ablation of MIEN1 inhibited cell migration, cell adhesion and altered the phosphorylation status of motility markers. Immunofluorescence staining with FITC- conjugated-phalladoin confirmed that alteration of MIEN1 expression leads to reconfiguration of the actin cytoskeleton in breast cancer cells. Furthermore we found that MIEN1 associates with cytoskeletal proteins involved in motility processes.

Conclusion: Our results show that MIEN1 is a critical regulator of cell migration and invasion. The importance of MIEN1 in tumor cell dissemination is well established; understanding the molecular mechanisms aiding the processes involved will enable the design of novel and effective treatments for metastatic tumors.

Citation Format: Marilyne Kpetemey, Jamboor Vishwanatha. MIEN1 drives breast cancer invasion by regulating cytoskeletal dynamics. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 520. doi:10.1158/1538-7445.AM2015-520
Abstract 5201: Antimetastatic effect of a Dializable Leucocyte Extract in a murine model of prostate cancer
Authors: Hernandez-Esquivel Miguel A. , Perez-Tapia Sonia M. , Pestell Richard G. , Velasco-Velazquez Marco A.
Published: August 2015

Prostate cancer remains the most common non-dermatological cancer in the United States and the second leading cause of cancer death amongst men. The majority of men with progressive prostate cancer develop metastases, being the skeleton the most prevalent metastatic site. Dialyzable leukocyte extracts (DLEs) are heterogeneous mixtures of low-molecular-weight (<10 kDa) peptides that improve clinical responses in various diseases. Our group has shown that DLEs change cytokine serum concentrations in patients and reduce experimental metastasis in a melanoma model. In this work we analyzed the in vitro effects of a human DLE produced under good manufacturing procedures and facilities [1] and evaluated its possible antimetastatic effect in vivo.

We employed PC-3 cells and murine Src-transformed Prostate Epithelial Cells (PEC-Src) to assess the direct effects of DLE in prostate cancer cells. Both cell lines were exposed in vitro to the DLE (1 pg/mL- 1 μg/mL) in proliferating (+FBS) or non-proliferating (-FBS) conditions, and cell number was estimated by MTS assays. The effects on cell motility and cell invasion were evaluated by wound healing assays and invasion from collagen-embedded spheroids, respectively. Since DLEs are immunomodulators, we used an experimental metastasis model that consistently produces bone and brain metastasis in inmunocompetent mice [2]. PEC-Src expressing Luciferase2-RFP were intracardiacally injected to FVB mice and metastatic growth in DLE-treated (1, 5, or 25 μg/kg p.o.) animals was quantified weekly by bioluminescence imaging.

In vitro exposure to a wide range of DLE concentrations did not alter proliferation or survival in PC-3 or PEC-Src cells, indicating that the evaluated DLE does not has direct antineoplastic effect. Similarly, treatments did not alter prostate cancer cell motility or invasion. In contrast, DLE (1 μg/kg) reduced metastatic tumor burden in brain and bones in inmunocompetent mice. The absence of direct effect on prostate cancer cells suggests that DLE-treatment may be changing cellular or soluble facilitators in the metastatic microenvironments. Supported by PAPIIT-UNAM IN219613.

[1] Medina-Rivero E, et al. J Pharma Biomed Anal 88: 289-294, 2014

[2] Sicoli D, et al. Cancer Res 74: 7103-14, 2014

Citation Format: Miguel A. Hernandez-Esquivel, Sonia M. Perez-Tapia, Richard G. Pestell, Marco A. Velasco-Velazquez. Antimetastatic effect of a Dializable Leucocyte Extract in a murine model of prostate cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5201. doi:10.1158/1538-7445.AM2015-5201
Abstract 5209: Non-tumoral autotaxin stored into platelet α-granules promotes breast cancer cell metastasis
Authors: Leblanc Raphael , Lee Sue-Chin , Norman Dereck , Ribeiro Johnny , Tigyi Gabor , Peyruchaud Olivier
Published: August 2015

Autotaxin (ATX) through its lysophospholipase D activity controls physiological levels of lysophosphatidic acid (LPA) in blood. ATX is overexpressed in multiple types of cancers and we have shown previously that together with LPA generated during platelet activation promotes skeletal metastasis of breast cancer. However, the mechanisms that regulate the pathophysiological significances of the interactions between circulating LPA, ATX, and platelets remain undefined in cancer. Here we show that ATX is stored in α-granules of resting human platelets and released upon tumor cell-induced platelet aggregation, leading to the production of LPA. For this study, we used two human breast cancer cell lines (MDA-MB-231, MDA-B02) that do not express ATX. Our in vitro and in vivo experiments demonstrate that non-tumoral ATX controls the early stage of bone colonization by tumor cells and to a less extent osteolytic bone metastasis progression. Moreover, expression of a dominant negative integrin αvβ3-Δ744 or treatment with the anti human αvβ&;3 monoclonal antibody LM609 completely abolished binding of ATX to tumor cells, demonstrating the requirement of a fully active integrin αvβ3 in this process. The present results establish a new mechanism for platelet contribution to LPA-dependent metastasis of breast cancer cells and demonstrate the therapeutic potential of disrupting the binding of non-tumor-derived ATX with the tumor cells for the prevention of metastasis.

Citation Format: Raphael Leblanc, Sue-Chin Lee, Dereck Norman, Johnny Ribeiro, Gabor Tigyi, Olivier Peyruchaud. Non-tumoral autotaxin stored into platelet α-granules promotes breast cancer cell metastasis. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5209. doi:10.1158/1538-7445.AM2015-5209
Abstract 5213: RUNX2 modulates the angiogenic potential of human neuroblastoma cells
Authors: Gnanamony Manu , Mohanam Indra , Mohanam Sanjeeva
Published: August 2015

Neuroblastoma is the most common extracranial pediatric solid tumor with an undifferentiated status and characterized by heterogeneous clinical courses ranging from spontaneous regression to a very aggressive malignant progression. The RUNX gene family comprises RUNX1, RUNX2, and RUNX3 transcription factors and plays pivotal roles in development, differentiation and tumorigenesis. Hypoxia is known to be a significant physiological stress in the tumor microenvironment and is associated with tumor malignant phenotype. In this study, we examined the effects of hypoxia on the Runx2 expression in human neuroblastoma cells and the role of RUNX2 on angiogenic potential of neuroblastoma cells. Runx2 has two isoforms, Runx2-I and Runx2-II. Isoform I is controlled by the P2 proximal promoter whereas isoform II is transcribed from the P1 distal promoter. Increased expression of mRNAs of isoform I and II as well as intact isoform of RUNX2 was observed in NB1691 cells exposed to hypoxia. Furthermore, hypoxia enhanced the activity of a luciferase reporter containing Runx2 P1 promoter in NB1691 cells. Hypoxic exposure caused an increase in protein levels of RUNX2 as well as survivin, a RUNX2 downstream target gene in NB1691 cells. Hypoxia also stabilized RUNX2 protein levels in NB1691 cells without altering the stability of RUNX2 mRNA. Hypoxia enhanced angiogenic potential of NB1691 cells. Knockdown of Runx2 significantly decreased VEGF mRNA and protein in NB1691 cells exposed to hypoxia. A decrease in angiogenesis was observed in chorioallantoic membrane assay performed using conditioned medium collected from RUNX2 siRNA treated hypoxic NB1691 cells compared with control. Further, transcript levels were measured by PCR array of human angiogenesis pathway and the analysis showed down regulation of EDN1, FIGF, TEK and VEGF A mRNAs in hypoxic NB1691 cells treated with RUNX2 siRNA. In conclusion, our study suggests that hypoxia upregulates RUNX2 expression in NB1691 cells and knockdown of RUNX2 decreases the angiogenic potential of hypoxic NB1691 cells.

Citation Format: Manu Gnanamony, Indra Mohanam, Sanjeeva Mohanam. RUNX2 modulates the angiogenic potential of human neuroblastoma cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5213. doi:10.1158/1538-7445.AM2015-5213
Abstract 5215: Loss of Rpl22 promotes tumor progression through regulation of angiogenesis
Authors: Rao Shuyun , Stadanlick Jason E. , Cai Kathy Q. , Wiest David L.
Published: August 2015

Mutations in ribosomal proteins (RP) often cause bone marrow syndromes associated with increased risk for cancer development. We have shown that Rpl22 is a haploinsufficient tumor suppressor in T acute lymphoblastic leukemia (T-ALL). Indeed, loss of one Rpl22 allele accelerates T-cell lymphomagenesis in the murine Akt transgenic mouse model, by inducing the stem cell factor Lin28B in an NFκB-dependent manner. Moreover, mice lacking both Rpl22 alleles exhibited significantly increased thymic tumor size, which was associated with poor survival and markedly enhanced angiogenesis relative to Rpl22 heterozygous mice or wild type. The increased angiogenesis in the mediastinal mass was linked to upregulation of VEGFA and downregulation of S1P1. Loss of S1P1 is sufficient to block egress of lymphoma cells from thymus. Rpl22-deficient thymic lymphoma lines also exhibit enhanced growth upon adaptation to growth in vitro, and this is reversed by ectopic expression of Rpl22. Rpl22 expression also represses the expression of proteins that promote traversal of the cell cycle. Collectively, the increased tumor growth and angiogenesis, and the blockade of thymic egress contribute to the enlarged mediastinal masses observed in Rpl22-deficient mice. Rpl22-mutant T-ALL are a molecularly distinct subtype exhibiting increased aggression and treatment resistance. Accordingly, our identification of a number of signaling pathways controlled by Rpl22 may enable the development of novel strategies, such as targeting angiogenesis, in such cases of T-ALL.

Citation Format: Shuyun Rao, Jason E. Stadanlick, Kathy Q. Cai, David L. Wiest. Loss of Rpl22 promotes tumor progression through regulation of angiogenesis. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5215. doi:10.1158/1538-7445.AM2015-5215
Abstract 5216: Potential use of saliva and hair samples to identify genetic markers for anti-VEGF therapy
Authors: Xue Gloria R. , Xue Crystal R. , Shen Fei , Schneider Bryan P.
Published: August 2015

Anti-angiogenic therapy to block and disrupt tumor angiogenesis has been used in clinical treatment of various malignancies including: glioblastoma, colorectal, lung and kidney cancer. Currently, the most clinically effective anti-angiogenic agents are the humanized monoclonal antibody (bevacizumab) against vascular endothelia growth factor (VEGF) and the small molecule receptor-tyrosine-kinase inhibitors (RTKIs) of VEGF receptors. However, the therapeutic benefit varies substantially for many of these agents. Predictive biomarkers that are required for personalized treatment with these agents are currently not available. Recently the role of germline single-nucleotide polymorphisms (SNPs) has been investigated as potential biomarkers for anti-angiogenic treatments. The rationale is that these agents target the vasculature in host (vessels) rather than tumor tissue, which could mean that much of the variability is dictated by the host. Several studies reported the association of SNPs in VEGFA with differential outcomes from clinical trials with these agents. SNP genotyping assays in these studies used germline DNA extracted from blood. However, collection of peripheral blood is invasive. Saliva and hair that are known to contain genomic DNA can be used as noninvasive and convenient DNA sampling resources, but the limited quantity of DNA in the hair and the low quality of DNA in the saliva make genotyping assays non-reproducible.

We have sought to improve SNP genotype assays with DNA from saliva and hair by applying SNP target pre-amplification for genotyping five SNPs (rs699947, rs833061, rs1570360, rs201093, rs3025039) in VEGFA. The concordance of genotyping calls of individual SNP using DNA from blood, saliva and hair from the same volunteer was compared. Our preliminary results demonstrated that pre-amplification substantially improved genotyping calls with saliva DNA and hair DNA samples. The average genotyping call rate with saliva and hair samples was about 45% and 10%, respectively, without pre-amplification. The pre-amplification improved the call rate with saliva and hair samples to 100% and 94%, respectively. The current report may facilitate easier clinical sample collection for genetic tests for these SNPs.

Citation Format: Gloria R. Xue, Crystal R. Xue, Fei Shen, Bryan P. Schneider. Potential use of saliva and hair samples to identify genetic markers for anti-VEGF therapy. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5216. doi:10.1158/1538-7445.AM2015-5216
Abstract 5220: Inflamed and wound recovered tumor microenvironment contributions to lymphatic-mediated metastasis
Authors: Fink Darci Marie , Connor Alicia L. , Kelley Philip M. , Tempero Richard M. , Hollingsworth Michael A.
Published: August 2015

Despite the clinical importance of lymph node status in cancer staging, treatment decisions, and patient outcomes, little is known about the earliest events of lymphatic-mediated metastasis of tumor cells. Lymphatic vessels remodel dramatically in response to changes in the inflammatory status of a tissue. Inflammation induces lymphangiogenesis and the resolution of inflammation stimulates lymphatic vessel regression. This study addresses one of the fundamental questions in metastasis biology and places it in the context of a specific microenvironmental state: how does a tumor cell gain entrance to a lymphatic vessel to migrate to a regional lymph node and what is the contribution of inflammation to this process? We sought to better understand lymphatic-mediated metastasis of tumor cells during inflammatory lymphangiogenesis or the resolution of inflammation. We hypothesized that manipulating the inflammatory status of the tumor microenvironment would alter tumor cell and lymphatic endothelium biology to influence lymphatic-mediated metastasis. We have previously established a corneal model of sutured-induced inflammatory lymphangiogenesis and a complimentary experimental arm of inflammation resolution. We transitioned this platform into real-time live imaging studies by using this corneal model in our novel transgenic mouse model background that inducibly expresses fluorescent tdTomato protein in the lymphatic endothelium (LyveCreERT2tdT). CFSE-labeled syngeneic tumor cells were introduced systemically via tail vein injection or locally into a corneal micropocket. Two-color intravital fluorescent stereomicroscopy allowed us to simultaneously track the fate of CFSE+ tumor cells at single-cell resolution and the morphologic changes in the tdTomato+ corneal lymphatic vessels during inflammatory lymphangiogenesis and lymphatic vessel regression. One major finding was the low frequency of lymphatic-mediated metastasis during both inflammation and resolution. Ongoing work continues to explore the contributions of specific cytokines to tumor-lymphatic endothelium interactions and the unique properties of a wound-recovered tumor microenvironment.

Citation Format: Darci Marie Fink, Alicia L. Connor, Philip M. Kelley, Richard M. Tempero, Michael A. Hollingsworth. Inflamed and wound recovered tumor microenvironment contributions to lymphatic-mediated metastasis. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5220. doi:10.1158/1538-7445.AM2015-5220
Abstract 5221: Mammary tumor aggressiveness is exacerbated by endothelial HoxA5 expression
Authors: Northcott Josette , Layman Hans , Boudreau Nancy
Published: August 2015

Despite evidence showing a positive correlation between angiogenesis and solid tumor progression, anti-angiogenic therapies have yielded limited, and often, tissue-specific responses. Whereas colorectal and renal cancers show improved responses, anti-angiogenic therapy has not proven effective at clinically managing breast tumor progression or prolonging patient survival. Moreover, anti-angiogenic treatment may promote the emergence of tumors with increased aggression and resistance to standard chemotherapies. Our laboratory has shown that sustained endothelial expression of the anti-angiogenic HoxA5 homeodomain transcription factor reduces angiogenesis and delays progression of squamous cell carcinoma in the KRT14-HPV16 mouse model of skin cancer. We subsequently investigated, whether constitutive endothelial expression of HoxA5 could also impede mammary tumor growth and metastasis. Surprisingly, we observed that endothelial HoxA5 expression increased both primary tumor growth and lung metastasis in the MMTV-PyMT mouse model of breast cancer. Primary tumors from PyMT/HoxA5+ mice exhibited an increased number of large vessels but were significantly more hypoxic, as compared to tumors from control mice. Orthotopic injection of isolated mammary tumor cells from PyMT/HoxA5+ mice into wild-type animals also resulted in larger tumors, as compared to tumor cells isolated from PyMT mice of the same age. Interestingly, although metastasis was increased in the PyMT/HoxA5+ transgenic mice, we did not detect differences in circulating tumor cells, suggesting that tumor cells from PyMT/HoxA5+ mice have increased tumor initiating potential. Thus, while anti-angiogenic HoxA5 expression in the endothelium delays skin tumor progression, more aggressive tumors arise in the mammary gland. We are currently evaluating the response of breast tumors in PyMT/HoxA5+ mice to standard cancer chemotherapeutics, as well as evaluating novel approaches to potentially target more aggressive tumors emerging from chronic hypoxic conditions.

Citation Format: Josette Northcott, Hans Layman, Nancy Boudreau. Mammary tumor aggressiveness is exacerbated by endothelial HoxA5 expression. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5221. doi:10.1158/1538-7445.AM2015-5221
Abstract 5224: Non-canonical activity of threonyl-tRNA synthetase promotes angiogenesis and invasion in a mouse model of ovarian cancer
Authors: Wo Peibin , Wellman Theresa , Howe Alan , Francklyn Christopher , Lounsbury Karen M.
Published: August 2015

Despite clear connections between the tumor microenvironment and ovarian cancer invasion, the underlying molecular mechanisms remain elusive. We have recently shown that the protein synthesis regulator threonyl-tRNA synthetase (TARS) has a unique extracellular angiogenic activity separate from its canonical function. Secreted TARS promotes endothelial cell migration and tube formation, and a selective TARS inhibitor, BC194, disrupts normal vessel development in zebra fish and chick embryo models. TARS expression also correlates with tumor stage and angiogenesis in human ovarian cancer. The objective of this study was to validate the biological and clinical relationship between TARS and ovarian tumor progression using a syngenic mouse model of epithelial ovarian cancer. Tumors were initiated by intraperitoneal injection of ID8 mouse ovarian cancer cells, and tumors formed at 4-6 weeks were scored for invasiveness and analyzed by immunostaining for TARS expression and microvascular density. To test the hypothesis that overexpression of TARS promotes invasion, cells were stably transfected with a TARS expression plasmid prior to injection. To test the hypothesis that TARS inhibition reduces tumor invasion, animals harboring ID8 tumors were treated with the high-affinity TARS inhibitor BC194. We found that TARS levels were elevated in ovarian tumors as compared with normal ovarian tissue. Overexpression of TARS in ID8 cells also resulted in enhanced invasiveness and microvascular density of the resulting tumors (p = 0.026). Preliminary results also indicated that inhibition of TARS by BC194 treatment reduced tumor angiogenesis and growth (p = 0.005) without observed toxicities in the animals. Overall, these results show that modifying TARS expression or activity can affect in vivo ovarian tumor angiogenesis and progression. These results encourage further study of TARS as a regulator of the tumor microenvironment and as a possible target for diagnosis and treatment of ovarian cancer.

Citation Format: Peibin Wo, Theresa Wellman, Alan Howe, Christopher Francklyn, Karen M. Lounsbury. Non-canonical activity of threonyl-tRNA synthetase promotes angiogenesis and invasion in a mouse model of ovarian cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5224. doi:10.1158/1538-7445.AM2015-5224