bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 4691: Overactivation of poly (ADP-ribose) polymerase (PARP) in localised non-small cell lung cancer (NSCLC) predicts dismal prognosis
Authors: Michels Judith , Goubar Aïcha , Adam Julien , Galluzzi Lorenzo , Olaussen Ken André , Robin Angélique , Girard Philippe , Kremer Isabelle , Castedo Maria , Soria Jean-Charles , Kroemer Guido
Published: May 2015

Recent studies underscore the general cytoprotective role of PARP1 and PAR in response to multiple extrinsic and intrinsic stress signals. Moreover, elevated levels of PARP have been correlated with increased tumor aggressiveness in breast cancer. Based on these premises, we decided to test whether PARP/PAR levels would be associated with prognosis in a cohort of localised NSCLC patients. Our cohort of patients underwent surgery from 1994 to 2002 and did not receive any chemotherapy. In these tumors, expression of PARP enzyme and the presence of its product, PAR, exhibited a significant, though not absolute, correlation, as determined by immunohistochemistry. The staining of PAR and PARP was almost exclusively nuclear, though highly variable in its intensity. Ninety-two NSCLC specimens were scored on a continuous scale of 0-300 and patients were stratified (separated by the median) into PAR low, PAR high, PARP low and PARP high groups. Tumor-infiltrating lymphocytes (which manifest high PARP and PAR levels) were used as an internal positive control of the staining procedure. Of note, among PARP low tumors, 32.5% were PAR high, indicating that low PARP protein levels do not preclude a high enzymatic activity. While high PAR levels had a significant negative impact on both disease-free (DFS) and overall survival (OS) (p=0.02 and 0.01, in univariate and 0.07 and 0.04 in multivariate analysis respectively), PARP expression did not correlate with either of these outcomes. We could validate PAR as a negative prognostic biomarker in a second cohort of 136 patients operated from 2002 to 2006. Altogether, these results identify high PAR levels as a biomarker of dismal prognosis in NSCLC.

Citation Format: Judith Michels, Aïcha Goubar, Julien Adam, Lorenzo Galluzzi, Ken André Olaussen, Angélique Robin, Philippe Girard, Isabelle Kremer, Maria Castedo, Jean-Charles Soria, Guido Kroemer. Overactivation of poly (ADP-ribose) polymerase (PARP) in localised non-small cell lung cancer (NSCLC) predicts dismal prognosis. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4691. doi:10.1158/1538-7445.AM2014-4691
Abstract 4721: Polymorphisms in cancer-related genes and survival in early stage non-small cell lung cancer
Authors: Lee Shin Yup , Choi Yi Young , Jeon Hyo-Sung , Choi Jin Eun , Kang Hyo-Gyoung , Yoo Seung Soo , Lee Eung Bae , Lee Won Kee , Lee Jaehee , Cha Seung Ick , Kim Chang H. , Son Ji Woong , Park Jae Yong
Published: May 2015

Background: This study was conducted to identify genetic polymorphisms associated with the prognosis of patients with early stage non-small cell lung cancer (NSCLC).

Materials and Methods: We genotyped 1,969 potentially functional single nucleotide polymorphisms (SNPs) of 1,151 genes using the Affymetrix custom-made GeneChip, which were related to the development and progression of cancer, in 166 NSCLC patients who underwent curative surgical resection. A replication study was performed on an independent cohort of 626 patients.

Results: Fifty six SNPs which were associated with both overall survival (OS) and disease-free survival (DFS) with log-rank P values lower than 0.05 in a discovery set were selected for validation. Among the 56 SNPs, five SNPs (guanine nucleotide binding protein, beta polypeptide 2-like 1 [GNB2L1] rs1279736C>A and rs3756585T>G, complement component 3 [C3] rs2287845T>C, p300/CBP-associated factor [PCAF] rs17006625A>G, and pericentriolar material 1 [PCM1] rs17691523C>G) were found to be significantly associated with survival outcomes in the same direction as the discovery set. In combined analysis, the rs1279736C>A and s3756585T>G were most significantly associated with OS and DFS in multivariate analysis (P for OS = 4x10-5 and 7x10-5, respectively; and P for DFS = 0.003, both; under a codominant model).

Conclusions: We identified five SNPs as markers for prognosis of patients with surgically resected NSCLC.

Citation Format: Shin Yup Lee, Yi Young Choi, Hyo-Sung Jeon, Jin Eun Choi, Hyo-Gyoung Kang, Seung Soo Yoo, Eung Bae Lee, Won Kee Lee, Jaehee Lee, Seung Ick Cha, Chang Ho Kim, Ji Woong Son, Jae Yong Park. Polymorphisms in cancer-related genes and survival in early stage non-small cell lung cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4721. doi:10.1158/1538-7445.AM2014-4721
Abstract 4776: PDK1-dependent activation of AGC kinases is an absolute requirement for AKT oncogenic activity
Authors: Orlacchio Arturo , Arciuch Valeria Antico , Cristofano Antonio Di
Published: May 2015

The PI3K signaling cascade is frequently activated in human cancer, and AKT is commonly considered its major transforming conduit. Thus, PI3K and AKT represent relevant targets for therapeutic purposes. However, the many essential of roles played by this pathway in normal cells poses the problem of reaching therapeutic efficacy without harming healthy tissues. In principle, it would be ideal to target only molecules directly involved in the transformation process, thus reducing the toxicity associated with wide-range inhibitors.

PDK1 plays a key role in the PI3K cascade, directly activating AKT. In addition, PDK1 possesses a substrate docking site named “PIF pocket” that is required to phosphorylate and activate members of the AGC kinase family, including S6K, PKC, SGK, and RSK.

Mice in which the PI3K pathway is constitutively activated in the thyroid epithelium through loss of Pten are born with thyroid hyperplasia that progresses to invasive and metastatic follicular carcinoma, a process that is accelerated by the simultaneous loss of p27 or p53, and by Ras or Braf activation.

Using in vivo as well as ex vivo and in vitro genetic and pharmacological approaches, we now show that although Akt activation is necessary, it is not sufficient to transform thyroid epithelial cells. Concomitant activation of Pdk1-dependent pathways is absolutely required to develop neoplastic lesions in vivo, and to induce cell proliferation ex vivo. Pten mutants develop adenomas and carcinomas by one year of age. Strikingly, complete rescue of this phenotype is observed in compound mutants in which, in addition to thyroid-specific Pten loss, the PIF-pocket of Pdk1 has been genetically disrupted, maintaining constitutive activation of Akt and mTor, but not of PIF-pocket dependent AGC kinases.

We also show that the transcription factor STAT3 represents a key mediator of this essential Pdk1-dependent pathway: STAT3 phosphorylation is increased in Pten mutants, and abolished in compound mutants. Furthermore, genetic and pharmacological inhibition of STAT3 drastically impairs cell proliferation in vitro and rescues the hyperplastic phenotype of Pten mutant mice in vivo.

Thus, we have identified an essential and druggable signaling cascade that critically cooperates with AKT activation to transform thyroid epithelial cells.

Citation Format: Arturo Orlacchio, Valeria Antico Arciuch, Antonio Di Cristofano. PDK1-dependent activation of AGC kinases is an absolute requirement for AKT oncogenic activity. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4776. doi:10.1158/1538-7445.AM2014-4776
Abstract 4807: Zoledronic acid overcomes the resistance to the anti-angiogenic therapy and normalizes tumor vessels by switching from a M2- to a M1-like macrophages phenotype in a mouse model of spontaneous cervical cancer
Authors: Capano Stefania , Maione Federica , Casanovas Oriol , Bussolino Federico , Giraudo Enrico
Published: May 2015

Recent studies described a resistance to the anti-angiogenic therapy both in pre-clinical and clinical settings. Several mechanisms that contribute to this resistance has been so far proposed and, among these, the recruitment of bone marrow-derived cells to the tumors, seems to be critical.

We have previously showed that an amino-bisphosphonate, Zoledronic acid (ZA), in a mouse model of spontaneous cervical carcinogenesis (HPV16/E2) by targeting MMP-9+ tumor-associated macrophages (TAM), strongly inhibited cancer progression and angiogenesis. Stemming from these data we sought to investigate whether ZA by acting on TAM, was able to overcome the resistance to anti-angiogenic treatments.

We treated tumor-bearing HPV16/E2 mice with ZA alone or combined with the small molecule tyrosine kinase inhibitor Sunitinib or with an anti-VEGFR-2 antibody, DC101, to assess the ability of ZA to block metastasis dissemination. Notably ZA synergized with Sunitinib and DC101 to inhibit primary tumor growth. Interestingly, while these compounds increased the incidence and the number of liver and lung metastasis, ZA alone inhibited basal tumor metastasis in parallel to angiogenesis inhibition. ZA combined with Sunitinib or DC101 showed a greater effect in impairing liver and lung metastasis formation. Confocal analysis of the vasculature revealed that while Sunitinib- or DC101-treated cancers displayed poorly functional vessels, both ZA alone or combined with Sunitinib or DC101 efficiently induced a normalized vasculature highly covered by pericytes and better perfused. Remarkably, gene and protein expression analysis of FACS-sorted macrophages derived from tumors of the different treatment groups, showed that ZA alone or combined with Sunitinib or DC101 inhibited the expression of M2-markers such as MRC-1, Il-10, CCL22 and MMP-9 and simultaneously enhanced the levels of M1-markers such as Il12 and CXCL9 in these cells.

We conclude that ZA, by promoting a M1-like macrophages phenotype in HPV16/E2 cervical cancers and consequently inducing a normalized vasculature, efficiently overcomes the resistance to angiogenesis inhibition by blocking metastasis dissemination.

Citation Format: Stefania Capano, Federica Maione, Oriol Casanovas, Federico Bussolino, Enrico Giraudo. Zoledronic acid overcomes the resistance to the anti-angiogenic therapy and normalizes tumor vessels by switching from a M2- to a M1-like macrophages phenotype in a mouse model of spontaneous cervical cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4807. doi:10.1158/1538-7445.AM2014-4807
Abstract 4832: Isolation and molecular characterization of circulating melanoma cells
Authors: Luo Xi , Mitra Devarati , Sullivan Ryan J. , Wittner Ben S. , Kimura Anya M. , Pan Shiwei , Hoang Mai P. , Brannigan Brian W. , Lawrence Donald P. , Flaherty Keith T. , Sequist Lecia V. , Stott Shannon L. , Ting David T. , Ramaswamy Sridhar , Toner Mehmet , Fisher David E. , Maheswaran Shyamala , Haber Daniel A.
Published: May 2015

Melanoma is a highly invasive malignancy frequently presenting with blood-borne metastases, in which recent breakthroughs in targeted and immunological therapies highlight the need for both early detection of invasion and monitoring of drug responses. We adapted a microfluidic device to capture circulating tumor cells (CTCs) in patients with melanoma and in a mouse model. In eight patients followed longitudinally, CTC numbers were correlated with response and progression on B-RAF/MEK, CDK4/6 and PDL1 inhibitors. Consistent with this trend, in a mouse model of tamoxifen-inducible B-RAF/PTEN-driven melanoma, CTCs declined within four days of treatment with a B-RAF inhibitor. In this model, CTCs are shed very early in tumorigenesis, and a four week course of B-RAF inhibition after resection of the primary tumor is sufficient to prevent the subsequent development of cutaneous metastases. Whereas primary and metastatic mouse melanomas are highly similar, RNA sequencing of CTCs identifies significant differences in expression, generating a signature that is correlated with invasiveness and motility in human melanoma.

Citation Format: Xi Luo, Devarati Mitra, Ryan J. Sullivan, Ben S. Wittner, Anya M. Kimura, Shiwei Pan, Mai P. Hoang, Brian W. Brannigan, Donald P. Lawrence, Keith T. Flaherty, Lecia V. Sequist, Shannon L. Stott, David T. Ting, Sridhar Ramaswamy, Mehmet Toner, David E. Fisher, Shyamala Maheswaran, Daniel A. Haber. Isolation and molecular characterization of circulating melanoma cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4832. doi:10.1158/1538-7445.AM2014-4832
Abstract 4887: Omentin: A novel adipokine in the omental microenvironment associated with ovarian cancer progression
Authors: Yeung Chi Lam Au , Co Ngai Na , Onstad Michaela , Yeung Tsz-Lun , Leung Cecilia S. , Schmandt Rosemarie , Lu Karen H. , Mok Samuel C.
Published: May 2015

Advanced stage serous ovarian cancer metastasizes preferentially to the omentum, which is a well-vascularized fold of peritoneal tissue and is a major site of intra-abdominal fat accumulation, suggesting that the omental microenvironment is a favorable niche for ovarian cancer cells. The 5-year survival drops to below 50% for the cancer cases that spread beyond the pelvis to the omentum. It has also become apparent that obesity contributes to a poor clinical outcome. The mechanisms by which omental adipose tissue promotes tumor growth and disease progression are not entirely clear.

Using transcriptome profiling analysis on the microdissected adipose tissue from patients with benign gynecologic diseases and from patients with advanced high-grade serous ovarian cancer (HGSOC), we identified a gene signature for ovarian cancer associated omental adipose tissue, suggesting that alteration of these genes in the ovarian cancer associated omental adipose tissue may generate a permissive microenvironment to support ovarian cancer growth. Among genes that are significantly up- or down-regulated in ovarian cancer associated adipose tissue compared with the normal adipose tissue, we seek to focus on evaluating the role of omentin (Intestinal Lactoferrin Receptor ITLN1) in ovarian cancer progression since it is a novel adipokine that is predominantly expressed and secreted by visceral adipose tissue and is barely detectable in subcutaneous fats. Our data showed for the first time that omentin was expressed predominantly by the mesothelial cells covering the visceral adipose tissue but not by other cell types in the omental adipose tissue. Interestingly, we showed that circulating omentin level is significantly lower in patients with HGSOC compared with those in the BMI matched healthy individuals. In addition, using monolayer culture models, we demonstrated that omentin suppressed ovarian cancer motility and invasion potential directly and ovarian cancer growth only in the presence of adipocytes. We also showed that omentin can increase insulin-dependent glucose up-take in adipocytes and omentin expression can be down-regulated by co-culturing with ovarian cancer cells and in the presence of TNF-α.

The study provides the first evidence that ovarian cancer cells modify the visceral adipose tissue through down-regulation of omentin to facilitate their growth in the omental microenvironment.

Citation Format: Chi Lam Au Yeung, Ngai Na Co, Michaela Onstad, Tsz-Lun Yeung, Cecilia S. Leung, Rosemarie Schmandt, Karen H. Lu, Samuel C. Mok. Omentin: A novel adipokine in the omental microenvironment associated with ovarian cancer progression. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4887. doi:10.1158/1538-7445.AM2014-4887
Abstract 4911: NSCLC cells demonstrate differential mode of cell death in response to the combined treatment of radiation and a DNA-PKcs inhibitor
Authors: Lan Yu , Shang Zengfu , Hsu Feng-Ming , Tumati Vasu , Chen Benjamin P. , Saha Debabrata
Published: May 2015

Introduction: Lung cancers demonstrate the highest number of p53 mutations of any cancer with 70% of small cell lung cancers and 33% of adenocarcinomas containing a mutation. Loss of p53 function has been correlated with therapeutic resistance and poor clinical outcomes. Therefore, developing therapeutic strategies that specifically target p53 loss-of-function mutants is of the utmost importance. The purpose of this investigation is to explore whether p53 status has impact on the radio-sensitizing effect of a DNA-PKcs inhibitor (NU7441).

Methods: Clonogenic surviving fraction analysis, DNA double strand break repair kinetics, cell cycle analysis, immunofluorescence, immunoblot, apoptosis and autophagy assays were used to investigate the mechanism of radiosensitization of NU7441 in NSCLC cell lines (A549, H1299, and H460) with differential levels of p53 expression.

Results: NU7441 substantially inhibited the repair of IR-induced DNA double strand break (DSB) in all three cell lines. Clonogenic surviving fraction analysis reveals that NU7441 is a better radio-sensitizer in p53-deficient cells (H1299) when compared to p53-wild type cells (A549, H460). Combination of ionizing radiation (IR) and NU7441 leads to a more robust G2 arrest in A549 and H460 cells when compared to radiation treatment only. However, NU7441 and radiation preferentially induced mitotic arrest in H1299 consequently leading to a significant increase in mitotic catastrophe. Furthermore, NU7441 led to an increase in apoptosis rather than autophagy as the predominant cell death pathway in p53-deficient cells. Moreover, knockdown of p53 using siRNA sensitized A549 to NU7441+IR treatment.

Conclusion: Our study clearly shows that NU7441, a novel DNA-PKcs inhibitor, is a potent radio-sensitizer in p53-dificient lung cancer cells and highlights the promise of NU7441 in targeted cancer treatment.

Citation Format: Yu Lan, Zengfu Shang, Feng-Ming Hsu, Vasu Tumati, Benjamin P. Chen, Debabrata Saha. NSCLC cells demonstrate differential mode of cell death in response to the combined treatment of radiation and a DNA-PKcs inhibitor. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4911. doi:10.1158/1538-7445.AM2014-4911
Abstract 4914: AKT- and ERK signaling inhibition does not sensitize GBM cells to chemo-/radiation in vitro
Authors: Narayan Ravi , Dik Rogier , Berg Jaap van den , Stalpers Lukas J.A. , Baumert Brigitta G. , Slotman Ben J. , Sminia Peter
Published: May 2015

A common feature of Glioblastoma Multiforme (GBM) is an augmented RTK/RAS/PI3K pathway signaling. This pathway has been shown to be involved in DNA repair by both NHEJ and HR in various tumor types and is thought thereby to interfere with its chemo- and radioresistance. Targeting this pathway to sensitize GBM to chemo- and radiotherapy seems to be an attractive therapeutic approach.

Proliferation and clonogenic survival of U251, U87 and T98 GBM cells were assessed following exposure to, BKM120 (pan class I PI3K inhibitor), RAD001 (mTORC1 inhibitor), MK-2206 (AKT inhibitor) and/or MEK162 (ERK inhibitor) alone and in combination with either irradiation or Temozolomide (TMZ). Effectivity of each compound on its target pathway was assessed by westernblot. BEZ235 (PI3K/mTOR/DNA-PK inhibitor) was used as a positive control for radiosensitization.

Our data show BKM120 and MK-2206 to effectively inhibit AKT phosphorylation at 1 uM and leads to growth inhibition in all tested cell lines. However, these compounds are not toxic on clonogenic cell survival and do not sensitize the cells to TMZ or irradiation. Increasing the dose to 5 uM and 10 uM for BKM120 and MK-2206 respectively an antagonistic effect was found in the combination with TMZ and irradiation. Effectively inhibiting mTOR, the downstream effector of AKT, by 100 nM RAD001 also does not radiosensitize GBM cells.

Inhibiting the parallel ERK-pathway by 1 uM MEK162, dephosphorylates ERK1/2 and leads to a slight increase in AKT phosphorylation. Inhibiting both pathways with BKM120 and MEK162 resulted in a synergistic growth inhibition of U251 cells however no radiosensitizing effect was found in a clonogenic assay.

In conclusion, selective targeting of key components in the AKT- and/or ERK signaling pathway effectively inhibits proliferation of GBM cells yet does not sensitize them to either TMZ or radiotherapy, indicating that GBM does not depend on the RTK/RAS/PI3K pathway for its DNA-repair.

Citation Format: Ravi Narayan, Rogier Dik, Jaap van den Berg, Lukas J.A. Stalpers, Brigitta G. Baumert, Ben J. Slotman, Peter Sminia. AKT- and ERK signaling inhibition does not sensitize GBM cells to chemo-/radiation in vitro. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4914. doi:10.1158/1538-7445.AM2014-4914
Abstract 4919: Visible/NIR-activatable prodrug strategy for treating local tumors by the combination of photodynamic therapy and local chemotherapy
Authors: Rajaputra Pallavi , Bio Moses , Nkepang Gregory , You Youngjae
Published: May 2015

Photodynamic therapy (PDT) and neoadjuvant chemotherapy have been used for treating localized tumors. However, each has its shortcomings such as limited efficacy to larger tumors and systemic side effects. We proposed a novel prodrug strategy by combining PDT and localized chemotherapy, which overcomes the problems of PDT and chemotherapy. A prodrug is composed of a photosensitizer and an anticancer drug connected via singlet oxygen (SO)-cleavable linker. Thus, SO generated by the illumination (690 nm) of the prodrug will not only directly damage tumors but also release active drug to kill surviving cancer cells. In our recent paper, we demonstrated the concept of our visible/NIR-activatable prodrug expressing the combination effect of PDT and local chemotherapy. We prepared CMP-L-CA4 where CMP = core-modified porphyrin (photosensitizer), CA4 = combretastatin A-4 (anticancer drug), and L = aminoacrylate linker (SO-cleavable linker) and its pseudo-prodrug (CMP-NCL-CA4: NCL = non-cleavable linker). CMP-L-CA4 showed desirable characteristics such as > 80% drug release in test tubes in 10 min, 6 times reduction in IC50 by illumination, and bystander effect. On the other hand, CMP-NCL-CA4 showed smaller increase in IC50 by illumination and did not show the bystander effect. Consistent with the in vitro results, CMP-L-CA4 showed significantly better antitumor effect than CMP-NCL-CA4. Recently, we developed improved prodrugs using phthalocyanine (Pc) as a photosensitizer. In our presentation, we will show our newer biological data with the prodrugs supporting our novel prodrug strategy.

Citation Format: Pallavi Rajaputra, Moses Bio, Gregory Nkepang, Youngjae You. Visible/NIR-activatable prodrug strategy for treating local tumors by the combination of photodynamic therapy and local chemotherapy. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4919. doi:10.1158/1538-7445.AM2014-4919
Abstract 4940: Perivascular macrophages induce localized, transient blood vessel permeability and tumor cell intravasation
Authors: Harney Allison S. , Arwert Esther N. , Entenberg David , Wang Yarong , Jones Joan G. , Condeelis John S.
Published: May 2015

Metastasis is a multistep process involving tumor and stromal cells. The microanatomical site consisting of a perivascular macrophage interacting with a Mena over-expressing tumor cell has been named the “tumor microenvironment of metastasis” (TMEM). TMEM density predicts distant metastatic recurrence in breast cancer patients making the study of TMEM function essential. In spontaneous orthotopic mouse mammary tumors (MMTV-PyMT), as the tumor progresses to malignancy tumor cells have increased Mena expression and assemble TMEM. TMEM assembly is correlated with elevated levels of circulating tumor cells and lung metastases, indicating a functional role for TMEM in tumor cell dissemination. High-resolution multiphoton-based microscopy at single cell resolution has revealed transient blood vessel permeability events at TMEM, marked by the extravasation of otherwise impermeable serum markers such as Qdots and fluorescent 155 kDa dextran. In proximity to sites of permeability there is increased tumor cell and macrophage motility towards the blood vessel, and local intravasation of tumor cells. Blocking macrophage function results in decreased blood vessel permeability and decreased numbers of circulating tumor cells. TMEM-associated macrophages produce VEGF-A, and blocking VEGF-A reduces blood vessel permeability and circulating tumor cells. The observation that TMEM mediates tumor cell intravasation through localized blood vessel permeability in live animals demonstrates that TMEM is a key metastatic microenvironment in the primary tumor, explains the prognostic value of TMEM density in predicting distant metastatic recurrence in breast cancer patients and suggests a potentially valuable re-tasking of existing anti-angiogenesis drugs.

This research is supported by the Department of Defense [Breast Cancer Research Program)] under award number BC120227 (ASH).

Note: This abstract was not presented at the meeting.

Citation Format: Allison S. Harney, Esther N. Arwert, David Entenberg, Yarong Wang, Joan G. Jones, John S. Condeelis. Perivascular macrophages induce localized, transient blood vessel permeability and tumor cell intravasation. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4940. doi:10.1158/1538-7445.AM2014-4940
Abstract 4975: Identification of a novel interaction between EZH2 and p38 in triple negative breast cancer
Authors: Anwar Talha , Moore Heather , Gonzalez Maria E. , Kleer Celina
Published: May 2015

Background: Breast cancer accounts for more than 40,000 deaths yearly in the United States, the majority of which are due to metastatic disease. The histone methyltransferase EZH2 (Enhancer of Zeste Homolog 2) is a member of the polycomb repressive complex 2 (PRC2) responsible for transcriptional repression by trimethylation of histone H3 at lysine 27. EZH2 is an independent predictor of recurrence and mortality that is overexpressed in 55% of invasive breast carcinomas. We previously identified a novel link between EZH2 and the p38 mitogen-activated protein kinase, an important mediator of breast cancer progression and metastasis. EZH2 binds to p38, and overexpression of EZH2 leads to phosphorylation and activation of p38. Based on in vitro evidence and recent studies implicating EZH2 in the methylation of non-histone targets, we hypothesized that EZH2 may methylate p38 in breast cancer cells. We further hypothesized that this methylation event may be important for p38 activation or stability.

Methods: In order to test this hypothesis, we used stable shRNA knockdown of EZH2 in MDA-MB-231 and SUM149 breast cancer cell lines. We performed co-immunoprecipitation using p38 and pan-methyl lysine antibodies to assess changes in methylated p38 by immunoblot. We are currently performing LC MS/MS analysis to identify the specific residues that are methylated by PRC2 both in vitro and in vivo. Additionally, in order to localize this interaction, we performed co-immunoprecipitation experiments on fractionated MDA-MB-231 and SUM149 lysates.

Results: Stable knockdown of EZH2 resulted in reduced methylated p38 compared to vector controls, suggesting that EZH2 methylates p38 in vivo. We found that EZH2 and p38 interact in nuclear and, surprisingly, cytoplasmic fractions.

Conclusions. We provide evidence that in addition to being a nuclear protein, EZH2 can be found in the cytoplasm of TNBCs, where it is able to complex with p38. Taken together, our data suggest that p38 methylation may represent an additional mechanism by which EZH2 mediates breast cancer progression in TNBC.

Citation Format: Talha Anwar, Heather Moore, Maria E. Gonzalez, Celina Kleer. Identification of a novel interaction between EZH2 and p38 in triple negative breast cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4975. doi:10.1158/1538-7445.AM2014-4975
Abstract 503: Antioxidants markedly accelerate tumor growth and reduce survival in mice with KRAS- and BRAF-induced lung cancer by disrupting the ROS-p53 axis
Authors: Sayin Volkan I. , Ibrahim Mohamed X. , Larsson Erik , Nilsson Jonas A. , Lindahl Per , Bergö Martin O.
Published: May 2015

Antioxidants are widely used to protect cells from damage induced by reactive oxygen species (ROS). The concept that antioxidants can help fight cancer is deeply rooted in the general population, promoted by the food supplement industry, and supported by some scientific studies. However, clinical trials have reported inconsistent results. Here, we show that supplementing the diet with the antioxidants N-acetylcysteine (NAC) or vitamin E markedly increases tumor progression and reduces survival by 50-60% in mouse models of B-RAF- and K-RAS-induced lung cancer. RNA sequencing revealed that NAC and vitamin E, which are structurally unrelated, produce highly coordinated changes in tumor transcriptome profiles, dominated by reduced expression of endogenous antioxidant genes. NAC and vitamin E increase tumor cell proliferation by reducing ROS, DNA damage, and p53 expression in mouse and human lung tumor cells. Inactivation of p53 increases tumor growth to a similar degree as antioxidants and abolishes the antioxidant effect. Thus, antioxidants accelerate tumor growth by disrupting the ROS-p53 axis. Because somatic mutations in p53 occur late in tumor progression, antioxidants may accelerate the growth of early tumors or precancerous lesions in high-risk populations such as smokers and patients with chronic obstructive pulmonary disease who receive NAC to relieve mucus production.

Citation Format: Volkan I. Sayin, Mohamed X. Ibrahim, Erik Larsson, Jonas A. Nilsson, Per Lindahl, Martin O. Bergö. Antioxidants markedly accelerate tumor growth and reduce survival in mice with KRAS- and BRAF-induced lung cancer by disrupting the ROS-p53 axis. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 503. doi:10.1158/1538-7445.AM2014-503
Abstract 5091: Aneuploidy is in stomatin overexpressed cells
Authors: Lee Jui-Hao , Lin Chi-Hung
Published: May 2015

A 31.5 kDa membrane associated protein which is highly abundant in the lipid rafts is stomatin. Human gene expression profile from UCSC Genome Bioinformatics databank indicates that stomatin is major in the peripheral blood, adipose tissue, muscle, and bone marrow. In the beginning, stomatin was thought to be involved in the disease OHSt (overhydrated hereditary stomatocytosis), and therefore named stomatin. However, later studies did not reveal mechanistic role of stomatin in mediating OHSt by evaluating stomatin gene deleted mice; the function of stomatin is therefore remained unclear. In this study, we found that overexpression of stomatin was able to induce the multinucleated cell formation. Our data also demonstrated that stomatin made in the cytoplasm could be transported outside of the cell and released to the culture medium. While adding the culture medium or condition medium to the cells, which did not contain exogenous stomatin, these cells were also triggered to undergo formation of multinucleated cells. Additionally, the stomatin induced multinucleated cells presented aneuploidy and abnormal centrosome number. Possible mechanisms underlying functions of stomatin that induce multinucleated cells are investigated.

Note: This abstract was not presented at the meeting.

Citation Format: Jui-Hao Lee, Chi-Hung Lin. Aneuploidy is in stomatin overexpressed cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5091. doi:10.1158/1538-7445.AM2014-5091
Abstract 5097: Co-targeting of convergent, switchable nucleotide biosynthetic pathways induces synthetic lethality in leukemia
Authors: Radu Caius G. , Nathanson David A. , Czernin Johannes
Published: May 2015

Pharmacological targeting of metabolic processes in cancer must overcome redundancy in biosynthetic pathways. Deoxycytidine triphosphate (dCTP) can be produced by the de novo pathway (DNP) via ribonucleotide reductase, and/or by the nucleoside salvage pathway (NSP) via deoxycytidine kinase (dCK). The NSP's role in supporting tumor DNA replication is unknown. Here we show that survival of acute lymphoblastic leukemia cells upon inhibition of DNP-dependent dCTP production requires a functional NSP. Thus, DNP inhibition triggers a compensatory switch to NSP-mediated dCTP production. This metabolic switch can be imaged by positron emission tomography, thereby providing a non-invasive method for monitoring pharmacological targeting of the DNP. Blocking both DNP dCTP production using thymidine and the switch to NSP using a new dCK inhibitor induces replication stress overload and synthetic lethality in leukemia cells, without significant host toxicity. This co-targeting therapy may be broadly applicable against other malignancies characterized by high levels of replication stress.

Citation Format: Caius G. Radu, David A. Nathanson, Johannes Czernin. Co-targeting of convergent, switchable nucleotide biosynthetic pathways induces synthetic lethality in leukemia. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5097. doi:10.1158/1538-7445.AM2014-5097
Abstract 512: Cell-based analysis of oxidative stress, lipid peroxidation and lipid peroxidation-derived protein modifications using fluorescence microscopy
Authors: Mandavilli Bhaskar S. , Aggeler Robert
Published: May 2015

Oxidative stress plays an important role in the progression of several diseases including inflammation, atherosclerosis, aging and age-related degenerative disorders. Reactive oxygen species damage membrane bound lipids resulting in lipid peroxidation-derived protein modifications. Cell-based measurements of oxidative stress, lipid peroxidation and protein carbonylation by traditional fluorescence microscopy provide a powerful platform to quantitate oxidative stress and lipid peroxidation. Here, we used three different approaches to measure oxidative stress and lipid peroxidation in cells by fluorescence microscopy. 1) Two new fluorogenic probes, CellROX™ Orange and CellROX ™ Green Reagents to measure oxidative stress in cells, 2) Image-iT® Lipid Peroxidation Kit for a ratiometric determination of lipid peroxidation in live cells 3) Click-iT® Lipid Peroxidation Imaging Kit, a click chemistry-based approach which utilizes incorporation of an alkyne-modified unsaturated fatty acid analog, linoleamide, into the cellular membranes. The resulting oxidation products, like 9, 12-dioxo-10(E) dodecenoic acid (DODE) can readily modify proteins and these modifications were readily detected in fixed cells by the copper-catalyzed click reaction using fluorescent azides. Using these approaches, we measured oxidative stress and lipid peroxidation caused by several oxidants in cells. Increases in oxidative stress, lipid peroxidation, and protein modifications were assessed by high content imaging and analysis as well as traditional fluorescence microscopy. In the models tested, at least 2-3 fold increases were observed compared to controls was and responses were successfully inhibited by antioxidants. The three strategies described here provide powerful new tools for the assessment of oxidative stress in cells and convey distinct advantages over existing cell-based methods.

Citation Format: Bhaskar S. Mandavilli, Robert Aggeler. Cell-based analysis of oxidative stress, lipid peroxidation and lipid peroxidation-derived protein modifications using fluorescence microscopy. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 512. doi:10.1158/1538-7445.AM2014-512
Abstract 5159: The histone methyltransferase SUV39H2 is a novel target of anticancer therapy
Authors: Sone Kembun , Nakamura Yusuke , Hamamoto Ryuji
Published: May 2015

Besides genetic disorders, dysregulation of epigenetic machinery has been proved to play a crucial role in human carcinogenesis, and the histone methylation/demethylation process has been considered as one of key regulators for this event. In this study, we demonstrate that one of the HMTs, suppressor of variegation 3-9 homolog 2 (SUV39H2), plays pivotal roles in human carcinogenesis. Quantitative real-time PCR revealed that SUV39H2 is aberrantly overexpressed in lung cancer, bladder cancer and multiple myeloma compared with their corresponding normal tissues, and immunohistochemical analysis revealed its positive staining in 251 out of 392 lung cancer cases and 16 of 29 bladder cancer cases, while no significant staining was observed in various normal tissues we examined. cDNA microarray analysis using a number of clinical tissues also confirms overexpression of SUV39H2 in various types of cancer. SUV39H2-specific small interfering RNAs significantly knocked down its expression, and caused the G1 arrest as well as suppression of cancer cell growth. Since SUV39H2 expression was undetectable in the normal tissues, SUV39H2 is considered to be an ideal target for development of tumor-specific therapeutics.

Citation Format: Kembun Sone, Yusuke Nakamura, Ryuji Hamamoto. The histone methyltransferase SUV39H2 is a novel target of anticancer therapy. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5159. doi:10.1158/1538-7445.AM2014-5159
Abstract 5161: The development of therapeutic inhibitors of the KDM5 histone demethylases
Authors: Hudlebusch Heidi R. , Heinemann Bo , Nielsen Jesper M. , Kleine-Kohlbrecher Daniela , Hauge Camilla , Boesen Thomas , Labelle Marc , Gerlach Lars-Ole , Staller Peter , Birk Peter
Published: May 2015

Histone methyl marks contribute to the regulation of chromatin architecture and of DNA-based processes such as replication, repair and gene transcription. There is increasing evidence for alterations in histone methylation patterns in cancer and other human diseases. Importantly, aberrant methylation can contribute to deregulated gene expression and thereby to excessive proliferation, survival and metastasis of cancer cells.

Histone methyl transferases and demethylases establish a dynamic equilibrium of histone modifications, and the expression and activity of several members of these enzyme families are deregulated in human cancer. The jumonji C-domain histone H3K4me3/2 demethylase KDM5B/PLU1/JARID1B as well as its close relative KDM5A/JARID1A are potential oncogenes. Both proteins are overexpressed in human tumors and the gene encoding KDM5B is e.g. amplified in invasive breast cancer cells. Results obtained with RNA interference and targeted deletions in mice have provided additional support for a critical role of KDM5 demethylases in cancer cells.

EpiTherapeutics is developing novel cancer drugs targeting the enzymatic activity of histone demethylases. Here we present our recent progress in obtaining selective, potent, and cell-permeable inhibitors of the KDM5 demethylases. Biochemical and cellular activities, pharmacological data, and in vivo antitumor activity will be discussed.

Citation Format: Heidi R. Hudlebusch, Bo Heinemann, Jesper M. Nielsen, Daniela Kleine-Kohlbrecher, Camilla Hauge, Thomas Boesen, Marc Labelle, Lars-Ole Gerlach, Peter Staller, Peter Birk. The development of therapeutic inhibitors of the KDM5 histone demethylases. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5161. doi:10.1158/1538-7445.AM2014-5161
Abstract 5175: Re-analysis of breast invasive carcinoma (BRCA) TCGA copy number data improves tumor profiles
Authors: Culot Louis J. , O'Hara Andrea , Keshavan Raja , Che Zhiwei , Shams Soheil
Published: May 2015

Using the copy number and SNP- probes available in the TCGA level 1 data, reprocessed tumor profiles were more consistent with a control set in terms of median number of copy number events, sample ploidy, and breakpoint genes than the published “level 3” TCGA data. Probe-level data were analyzed using Nexus Copy Number SNP-FASST2 (a multi-state HMM algorithm that uses both SNP and copy number probes in making state assignments), with systematic correction applied to correct for GC biases. Additionally we performed manual baseline adjustment to correct for sample ploidy based on whole-genome B-alelle frequency data for each sample. The median number of copy number events in the TCGA data set was reduced from 377 (in the level 3 set) to 193, with a corresponding reduction in variance, and in line with our control samples (median CN changes of 173 and 142). After manual inspection, more than 15% of the TCGA BRCA samples available at level 3 were found to have incorrect baseline ploidy assignments. The resultant reanalyzed data set, along with associated clinical annotations for each sample, is available through Nexus DB repository to the general scientific community and should provide greater utility for further research.

Citation Format: Louis J. Culot, Andrea O'Hara, Raja Keshavan, Zhiwei Che, Soheil Shams. Re-analysis of breast invasive carcinoma (BRCA) TCGA copy number data improves tumor profiles. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5175. doi:10.1158/1538-7445.AM2014-5175
Abstract 5189: RNA editing in rhoq promotes invasion potential in colorectal cancer
Authors: Kim Hwang-Phill , Han Sae-Won , Lee Kyung-Hun , Park Kyu Joo , Seo Jeong-Sun , Kim Jong-Il , Kim Tae-You
Published: May 2015

RNA editing can increase RNA sequence variation without alteration of DNA sequence. By comparing whole genome and transcriptome sequence data of a rectal cancer, we have found a novel tumor specific RNA editing in RHOQ. The A-to-I editing results in substitution of sparagine with serine at residue 136. We observed higher level of the RHOQ RNA editing in tumor compared with normal tissue in colorectal cancer. The degree of RNA editing was associated with RhoQ activity in colorectal cancer cell lines. RhoQ N136S amino acid substitution increased RhoQ activity, actin cytoskeletal reorganization, and invasion potential. KRAS mutation further increased the invasion potential of RhoQ N136S in vitro. Among colorectal cancer patients, recurrence was more frequently observed in patients with tumors having edited RHOQ and mutant KRAS. Collectively, we show that RNA editing is another mechanism of sequence alteration contributing to colorectal cancer progression.

Citation Format: Hwang-Phill Kim, Sae-Won Han, Kyung-Hun Lee, Kyu Joo Park, Jeong-Sun Seo, Jong-Il Kim, Tae-You Kim. RNA editing in rhoq promotes invasion potential in colorectal cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5189. doi:10.1158/1538-7445.AM2014-5189
Abstract 5208: MiR-22 is frequently down-regulated in medulloblastomas, and inhibits cell proliferation via the novel target PAPST1
Authors: Xu Qing-Fu , Pang Jesse Chung-sean , Yang Hui , Lv Sheng-Qing , Ohgaki Hiroko
Published: May 2015

Medulloblastoma (WHO grade IV) is the most frequent malignant CNS tumor in children. MicroRNAs (miRNAs, miRs) are small non-coding RNAs that target protein-coding mRNAs that play roles in a variety of cellular processes through regulating multiple target genes. In the present study, we analyzed miR-22 expression and its effect on cell proliferation and apoptosis in medulloblastomas. Quantitative RT-PCR revealed significantly lower expression of miR-22 in 19/25 (76%) medulloblastomas, D341, DAOY and ONS-76 medulloblastoma cells and primary cultured medulloblastomas cells, compared to normal cerebellum. Forced expression of miR-22 by lentiviral vector transfection reduced cell proliferation and induced apoptosis in DAOY and ONS-76 cells. DAOY cells with miR-22 overexpression in nude mice yielded tumors smaller than those originated from control DAOY cells. Microarray analysis in DAOY cells with forced miR-22 expression showed significant changes in expression profiles; PAPST1 being the most significantly (10-fold) down-regulated gene. Quantitative RT-PCR revealed PAPST1 up-regulation in 18/25 (72%) medulloblastomas. Furthermore, the results of luciferase reporter assay in ONS-76 cells suggested that miR-22 directly targets the PAPST1 gene. Thus, frequently down-regulated miR-22 expression is associated with cell proliferation in medulloblastomas, at least in part via PAPST1, which is a novel target of miR-22.

Citation Format: Qing-Fu Xu, Jesse Chung-sean Pang, Hui Yang, Sheng-Qing Lv, Hiroko Ohgaki. MiR-22 is frequently down-regulated in medulloblastomas, and inhibits cell proliferation via the novel target PAPST1. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5208. doi:10.1158/1538-7445.AM2014-5208