bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 4228: Identification of distinct mammary cancer stem cells with differential requirements for the autophagy regulator FIP200
Authors: Yeo Syn K. , Wen Jian , Chen Song , Guan Jun-Lin
Published: August 2015

Cancer stem cells (CSCs) contribute to intratumoral heterogeneity and have been implicated in disease relapse and drug resistance. Added to this complexity is the idea that distinct CSC populations can coexist within a tumor and hence, the understanding of this diversity is imperative for effective therapeutic targeting. In this study, we show the co-existence of distinct breast CSC populations which can be identified by ALDH+ and CD29+CD61+ markers respectively using the MMTV-PyMT driven mouse model of breast cancer. While both of these populations exhibit enhanced tumor initiating potential in Nude mice relative to bulk tumor cells, the CD29+CD61+ population have increased invasive abilities and display higher expression of epithelial to mesenchymal (EMT) associated genes. As autophagy has been associated with the acquisition of breast CSC traits, we went on to address the requirement for autophagy in ALDH+ and CD29+CD61+ populations through the deletion of the autophagy regulator, FIP200 in MMTV-PyMT driven tumors. Interestingly, FIP200 deletion only reduces the percentage of CD29+CD61+ cells but does not affect the percentage of ALDH+ cells. However, the tumor initiating properties of both ALDH+ and CD29+CD61+ cells were impaired upon FIP200 deletion. The decrease in the number and CSC potential of CD29+CD61+ cells correlated with diminished TGF-beta signalling upon FIP200 deletion as indicated by decreased TGF-b2, TGF-b3 and phospho-SMAD2 levels. FIP200 deletion also reduced STAT3 activation and it remains to be addressed whether this is responsible for decreased CSC potential in ALDH+ cells. Altogether, our results demonstrate the presence of distinct CSCs in MMTV-PyMT tumors with potentially distinct requirements for divergent signaling pathways. Importantly, we also show that the autophagy regulator FIP200 plays a crucial role in governing the CSC properties of these distinct CSC populations and could represent a potential therapeutic target against breast CSCs.

Citation Format: Syn K. Yeo, Jian Wen, Song Chen, Jun-Lin Guan. Identification of distinct mammary cancer stem cells with differential requirements for the autophagy regulator FIP200. [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 4228. doi:10.1158/1538-7445.AM2015-4228
Abstract 4276: Engineering a trivalent lupus anti-DNA autoantibody fragment for cancer therapy
Authors: Patel Jaymin M. , Noble Phil W. , Chan Grace , Weisbart Richard H. , Hansen James E.
Published: August 2015

Discovery and design of agents that selectively kill malignant cells but spare normal tissue is critical to the development of effective cancer therapies. 3E10 is a lupus anti-DNA autoantibody that penetrates cell nuclei, binds DNA and inhibits DNA repair in a manner that does not kill normal cells but is synthetically lethal to cancer cells with defective homology-directed repair of DNA double-strand breaks due to BRCA2-deficiency. To develop a more potent version of 3E10 for further testing in cancer therapy, we have engineered a trivalent fragment of 3E10 with mutations that enhance nuclear penetration and DNA binding. cDNA encoding a tandem trivalent single chain variable fragment of 3E10 (3E10 tri-scFv) with the D31N enhancing mutation in CDR1 of the heavy chain variable regions was designed and cloned into the pPICZαA yeast expression vector. 3E10 tri-scFv was expressed in and purified from Pichia pastoris. Biochemical characterization of 3E10 tri-scFv by SDS-PAGE and Western blotting confirmed purification of the expected protein product, and cell-penetration assays demonstrated increased efficacy of nuclear uptake by 3E10 tri-scFv. Clonogenic survival assays with BRCA2-deficient cancer cells similarly indicated enhanced synthetic lethality mediated by 3E10 tri-scFv. These findings indicate 3E10 tri-scFv is a promising candidate for further development as a targeted therapy for DNA repair-deficient malignancies and demonstrate the potential utility in engineering multivalent derivatives of other promising lupus autoantibodies intended for development as targeted cancer therapies.

Citation Format: Jaymin M. Patel, Phil W. Noble, Grace Chan, Richard H. Weisbart, James E. Hansen. Engineering a trivalent lupus anti-DNA autoantibody fragment for cancer 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 4276. doi:10.1158/1538-7445.AM2015-4276
Abstract 4282: All-trans retinoic acid enhances the effector functions of the anti-CD38 antibody SAR650984
Authors: Bush Lucas , Harper David , Greco Rita , Song Zhili , Yang Guang , Adrian Francisco
Published: August 2015

SAR650984 is a humanized IgG1 monoclonal antibody selectively targeting CD38 that is in clinical development for the treatment of multiple myeloma (MM). SAR650984 eliminates MM cells through different mechanisms, including antibody dependent cytotoxicity and phagocytosis (ADCC and ADCP, respectively), complement dependent cytotoxicity (CDC), and direct induction of apoptosis. The aim of this study was to assess the cell killing activity of SAR650984 following genetic and chemical manipulation of CD38 expression in MM cells.

We established several MM cell lines engineered to overexpress CD38; median levels of CD38 were 537,000 receptors/cell, versus 29,000 receptors/cell in the parental cell lines. ADCC, ADCP, CDC, and apoptosis induced by SAR650984 treatment were all significantly increased in the CD38-overexpressing lines compared with the parental cell lines.

Based on these data, we hypothesized that pre-treatment of MM cells with all-trans retinoic acid (ATRA) would enhance the activity of SAR650984, since ATRA can induce up-regulation of CD38 expression. Treatment of the MM cell lines JJN-3, ARH-77, U266, Karpas-620, SKMM-2, RPMI-8226, NCI-H929, KMS-12PE and MOLP-8 with ATRA resulted in a dose-dependent 1.4- to 6.7-fold up-regulation of cell surface expressed CD38. Pretreatment of MM cells with ATRA for 48 hours resulted in enhanced SAR650984-mediated ADCC and ADCP compared to non-pretreated cells. The enhancement of ADCC and ADCP activity by ATRA pretreatment was recorded in all the cell lines tested.

In conclusion, these in vitro data are supportive of further evaluation of the combination of SAR650984 and ATRA for the treatment of MM.

Citation Format: Lucas Bush, David Harper, Rita Greco, Zhili Song, Guang Yang, Francisco Adrian. All-trans retinoic acid enhances the effector functions of the anti-CD38 antibody SAR650984. [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 4282. doi:10.1158/1538-7445.AM2015-4282
Abstract 430: MCP-1/CCL2 and IL-8 regulate proteolytic activity of triple negative inflammatory breast cancer via cathepsin B, ERK1/2, JAK1 and Src signaling pathways
Authors: Ibrahim Sherif A. , Elghonaimy Eslam A. , El-Shinawi Mohamed , El-Halawany Medhat , Nouh Mohamed A. , El-Mamlouk Tahani , Sloane Bonnie F. , Mohamed Mona Mostafa
Published: August 2015

Background

Inflammatory breast cancer (IBC) is the most aggressive form of breast cancer. Recently, we have shown that macrophages isolated from the tumor microenvironment of IBC patients secrete monocyte chemoattractant protein-1/CC-chemokine ligand 2 (MCP-1/CCL2) and IL-8 that augment dissemination and metastasis of IB carcinoma cells. However, the precise molecular mechanism by which these cytokines exert their effect is still unclear.

Methods

In the present study, the triple negative breast cancer (TNBC) cell lines Sum149 (IBC) and HCC70 (non-IBC) cells were employed to analyze the effect of IL-8 and MCP-1/CCL2 on the proteolytic activity using live cell imaging assay, expression of cathepsin B and the activation status of STAT3, AKT, JAK1 and Src. In addition, we enrolled TNBC patients sub-grouped into IBC (n = 15), non-IBC (n = 19) patients.

Results

Our results revealed that upon stimulation with MCP-1/CCL2 and IL-8, Sum149 cells and HCC70 exhibited an increase in DQ-collagen degradation-mediated proteolytic activity. Mechanistically, MCP-1/CCL2 and IL-8 increase collagen degradation via enhanced expression of cathepsin B single chain mature enzyme (31 kDa) and the heavy chain of double chain mature enzyme (25/26 kDa). Moreover, MCP-1/CCL2 and IL-8 enhance activation of STAT3, ERK1/2 and AKT in both Sum149 and HCC70 cells. Interestingly, we detected over-expression of cathepsin B in the carcinoma tissues of TNBC-IBC patients compared to non-IBC patients. Over expression of cathepsin B found to be associated with activation of Src and ERK1/2, in IBC as compared to non-IBC tissues.

Conclusions

Our data indicate that MCP-1/CCL2 and IL-8 stimulate proteolytic activity, cathepsin B expression and Src-ERK1/2 pathway in IBC tissues versus non-IBC. Targeting MCP-1/CCL2 and IL-8 in triple negative IBC patients represents a promising therapeutic strategy.

Citation Format: Sherif A. Ibrahim, Eslam A. Elghonaimy, Mohamed El-Shinawi, Medhat El-Halawany, Mohamed A. Nouh, Tahani El-Mamlouk, Bonnie F. Sloane, Mona Mostafa Mohamed. MCP-1/CCL2 and IL-8 regulate proteolytic activity of triple negative inflammatory breast cancer via cathepsin B, ERK1/2, JAK1 and Src signaling pathways. [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 430. doi:10.1158/1538-7445.AM2015-430
Abstract 4301: Endothelial angiopoietin-2 expression correlates with tumor angiogenesis and response to sunitinib in metastatic renal cell carcinoma
Authors: Lampinen Anita , Rautiola Juhana , Mirtti Tuomas , Ristimäki Ari , Joensuu Heikki , Bono Petri , Saharinen Pipsa
Published: August 2015

Background: Angiopoietin-2 (Ang2) is an endothelial cell derived growth factor, which promotes tumor angiogenesis, tumor growth and metastasis. Ang2 is a promising target for anti-angiogenic therapies, but its potential as a biomarker for anti-angiogenic therapies remains unknown. The purpose of this study was to evaluate expression of the Ang2-Tie2 signalling pathway components in metastatic RCC (mRCC) patients treated with sunitinib, a modern multitarget TKI.

Materials and methods: We evaluated Ang2, CD31 and Ki67 expression in tumors of 136 patients with metastatic RCC (mRCC) treated with first-line sunitinib from formalin-fixed paraffin-embedded tumor samples using immunohistochemistry.

Results: Ang2 was exclusively expressed in the endothelial cells of tumor blood vessels. Using a cutoff of ≥50 Ang2+ vessels/microscopic field, 38% of the samples had high Ang2 expression. High Ang2 expression correlated with high CD31+ vessel density (p = 0.002). 91% of patients with high Ang2 expression had partial response (PR) or stable disease (SD) as best response to sunitinib as compared with 76% of those with low Ang2 expression (P = 0.033). High CD31+ vessel density correlated with a high clinical benefit rate (P = 0.015), and with low levels of Ki-67+ tumor cells (P = 0.018). Combined high expression of both Ang2 and CD31 predicted even better clinical benefit rate with 100% of the patients with high Ang2 and CD31 expression (n = 25) achieving PR/SD as compared with 77% among the rest of the patients (n = 101; P = 0.007). Only one patient (8%, n = 12) with papillary RCC, but 49 (41%) patients with clear cell RCC had high Ang2 expression (P = 0.03).

Conclusions: In this first study to investigate Ang2 expression and outcome in mRCC patients treated with sunitinib, high Ang2 expression in the tumor vasculature was predictive for sunitinib efficacy.

Citation Format: Anita Lampinen, Juhana Rautiola, Tuomas Mirtti, Ari Ristimäki, Heikki Joensuu, Petri Bono, Pipsa Saharinen. Endothelial angiopoietin-2 expression correlates with tumor angiogenesis and response to sunitinib in metastatic renal cell 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 4301. doi:10.1158/1538-7445.AM2015-4301
Abstract 4304: MMP-9 as a marker of response to treatment with B-Raf inhibitors in cutaneous melanoma
Authors: Candido Saverio , Malaponte Grazia , Salemi Rossella , Pezzino Franca Maria , Scalisi Aurora , McCubrey James A. , Libra Massimo
Published: August 2015

Malignant melanoma is an aggressive tumor of the skin with a poor prognosis for patients with advanced disease. In melanoma, both the Ras/Raf/MEK/ERK (MAPK) and the PI3K/AKT (AKT) signaling pathways are constitutively activated through multiple mechanisms. Although, at present it has been demonstrated that the treatment with B-Raf enzyme inhibitors improve survival of melanoma patients, still these patients may relapse or become resistant to treatment. Therefore, there is a need to identify novel factors involved in melanoma development and/or progression.

Matrix metalloproteinases (MMP) have been regarded as critical molecules in promoting tumor cell metastasis. Prognostic and diagnostic significance of MMP-9 overexpression has been shown in several cancer types. However, their role in melanoma was not fully investigated. Thus, we hypothesized that MMP-9 overexpression in melanoma may be involved in transformation and act as a prognostic biomarker.

On this light, MMP-9 circulating levels, and MMP-9 gelatinase activity were measured by ELISA and zymography in a total of 148 melanoma samples with and without BRAFV600E mutation compared to healthy controls. The results showed that highest circulating levels of MMP-9 and MMP-9 activity were associated with advanced stages of disease. We have also demonstrated that higher levels of MMP-9 were detected among melanoma samples harboring BRAFV600E mutation compared to those BRAFWT.

We further investigated if MMP-9 may be associated with acquired resistance to B-Raf inhibitors, such as Dabrafenib. Functional in vitro experiments were performed using commercial available melanoma cell lines. The results showed that MMP-9 was down-regulated in melanoma cells after treatment with Dabrafenib. While, higher MMP-9 expression levels were observed in the resistant clones compared to those detected in the parental cells. Intriguingly, similar trend was observed for pERK expression.

Overall, these data indicate that MMP-9 may play a role for the evaluation of response to treatment with B-Raf inhibitors in melanoma patients.

Note: This abstract was not presented at the meeting.

Citation Format: Saverio Candido, Grazia Malaponte, Rossella Salemi, Franca Maria Pezzino, Aurora Scalisi, James A. McCubrey, Massimo Libra. MMP-9 as a marker of response to treatment with B-Raf inhibitors in cutaneous 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 4304. doi:10.1158/1538-7445.AM2015-4304
Abstract 4307: In vitro drug sensitivity and genetic profile analysis from primary culture obtained from brain cancer
Authors: Kipper Franciele C. , Mendonça Louise C. , Becker Rafael , Confortin Gláucia , Ledur Pítia F. , Marc André , Paglioli-Neto Eliseu , Viola Fabiana , Morrone Fernanda B. , Lenz Guido
Published: August 2015

The Cancer Genome Atlas effort subtyped gliomas in four molecular groups based on gene expression, mutation and deletion and retrospectively linked these subtypes to chemotherapy response. But up to now there is no protocol to use this or other methods to predict chemotherapy response in the clinic for gliomas. Patients are normally treated with ratiotherapy and temozolomide (TMZ) in a protocol of 5 days of treatment and 23 days of recovery. The goal of this study is to analyze gene expression and drug sensitivity in a relevant time frame to prospectively contribute to therapeutic decisions. For this, we prepared 19 cell cultures from 19 biopsies of brain tumors and treated them with a range of chemotherapy agents (TMZ, carmustine, lomustine, cisplatin, etoposide, paclitaxel, irinotecan, procarbazin, mebendazol, vincristin and vinblastin) at plasmatic concentration. Cells were counted for at least 12 days after treatment or tested for viability after 7 or 14 days and more that 60% reduction was considered a positive response. From eleven cell cultures tested with viability assay, only one responded to temozolomide (the first line chemotherapy for this tumor) after a single administration. The strongest effect was obtained using anti-microtubule agents. Cell counting after 12 days of treatment confirmed the resistance to TMZ and the sensitivity to antimicrotubule drugs, particularly paclitaxel. Combination of procarbazin, lomustine and vincristine (PCV), previously used to treat glioblastoma patients, killed very effectively cells of only 1 patient. The cell cultures from three of five patients display EGFR over-expression and four of five presented p53 and p21 expression. At this time, we are not able to correlate gene expression, subtyping and drug sensitivity. From these data we conclude that brain tumors can be routinely grown and tested for drug sensitivity in a time frame that more closely mimics the treatment of patients.

Ethical protocol number UFRGS: 420.856; PUCRS: 429.849 Financial support: FAPERGS, CNPq e CAPES.

Citation Format: Franciele C. Kipper, Louise C. Mendonça, Rafael Becker, Gláucia Confortin, Pítia F. Ledur, André Marc, Eliseu Paglioli-Neto, Fabiana Viola, Fernanda B. Morrone, Guido Lenz. In vitro drug sensitivity and genetic profile analysis from primary culture obtained from brain 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 4307. doi:10.1158/1538-7445.AM2015-4307
Abstract 4327: Nek6 and Hif-1α cooperate with the cytoskeletal gateway of drug resistance to drive outcome in serous ovarian cancer
Authors: De Donato Marta , Fanelli Mara , Mariani Marisa , Raspaglio Giuseppina , Pandya Deep , He Shiquan , Fiedler Paul , Petrillo Marco , Scambia Giovanni , Ferlini Cristiano
Published: August 2015

Hypoxia selects the most aggressive and drug-resistant clones in solid malignancies. One of the pivotal transcription factors induced by hypoxia is Hif-1α. However, in serous ovarian cancer (SEOC), Hif-1α expression is not a prognostic biomarker. This study aims to assess the hypothesis that the serine-threonine kinase Nek6 functions as a downstream effector cooperating with Hif-1α in driving ovarian cancer aggressiveness.

Nek6 was overexpressed and Hif-1α was silenced in A2780 cells. Nek6 was also stably silenced in Hey cells. The dependence of Nek6 expression on Hif-1α was assayed as a function of hypoxic growth conditions. Nek6 interaction with the cytoskeletal gateway of drug resistance was investigated with far western blot. The co-expression of NEK6, HIF1A, TUBB3 and GBP1 transcripts was quantified with qPCR in two cohorts of SEOC patients (346 locally treated patients and 344 from the TCGA dataset).

Nek6 expression is induced by hypoxia in a Hif-1α dependent fashion. Nek6 directly interacts with GBP-1, thus being a component of the cytoskeletal gateway of drug resistance. Nek6 overexpression increases and silencing decreases the anchorage-independent growth of cultured cells. In SEOC patients, NEK6 expression is significantly correlated with HIF1A. Co-expression of NEK6, HIF1A, TUBB3 and GBP1 transcripts identifies a subset of SEOC patients characterized by poor outcome and drug resistance.

This study demonstrates the functional relevance of Nek6 in the context of the adaptive response to hypoxia in SEOC. This finding may help identify a sub-population of patients at high risk of relapse to standard first-line chemotherapy.

Citation Format: Marta De Donato, Mara Fanelli, Marisa Mariani, Giuseppina Raspaglio, Deep Pandya, Shiquan He, Paul Fiedler, Marco Petrillo, Giovanni Scambia, Cristiano Ferlini. Nek6 and Hif-1α cooperate with the cytoskeletal gateway of drug resistance to drive outcome in serous 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 4327. doi:10.1158/1538-7445.AM2015-4327
Abstract 4334: Elevated lactic acid is a negative prognostic factor in metastatic lung cancer
Authors: Vlachostergios Panagiotis J. , Parikh Nirav , Oikonomou Katerina , Gibilaro Eugene , Apergis George
Published: August 2015

Introduction: Hyperlactatemia with or without type B lactic acidosis is a rare complication of malignancy, previously observed most often in hematological malignancies. Underlying pathophysiology involves reduced lactic acid metabolism from metastatic liver dysfunction as well as overproduction of lactic acid from aberrant glycolytic metabolism of tumors. Clinical data to evaluate the potential value of arterial or venous lactic acid (LA) level assessment as a predictor of overall survival (OS) or/and response to treatment are lacking. The aim of this study was to assess the prognostic value of LA in patients with metastatic lung cancer.

Methods: Patients diagnosed with stage IV non-small cell lung cancer (NSCLC) or extensive stage small cell lung cancer (SCLC) from 2012 to present, were included in this single center, retrospective study. Patients with sepsis or acute exacerbation of heart failure were excluded from the study. Arterial and venous LA level, bicarbonate, anion gap, urine ketones, serum LDH were recorded for each patient and their associations with demographic and clinical data and OS were analyzed with the Chi-square test, Kaplan-Meier's actuarial method (log-tank test) and Cox proportional hazard model.

Results: 85 patients (43 males, mean age 73.1, range 45-96 years) were studied. The maximal levels of arterial or venous LA were significantly associated with presence of ≥2 metastatic sites (p = 0.001), ICU admission or transfer (p = 0.016), intubation (p = 0.029), elevated serum anion gap (p<0.001) and LDH levels (p<0.001). No significant associations emerged between LA level and gender, age, smoking status, histology, tumor size or grade, previous lung resection, location of metastases, COPD, previous metformin use, ketonuria, and previous or ongoing palliative chemotherapy. Hyperlactatemia (p<0.001), histologic subtype (p = 0.019), ICU admission or transfer (p = 0.014), intubation (p = 0.026), number of metastatic sites (p = 0.01), AG (p<0.01) and LDH (p<0.001) were univariately associated with OS. LDH was the only independent prognostic factor [OR = 0.162 (95% CI: 0038-0.687), p = 0.014].

Conclusion: Our results suggest that elevated LA is a predictor of poor OS in metastatic lung cancer patients, irrespective of chemotherapy. Here lie implications for targeting tumor-derived LA production via manipulation of glycolytic enzymes or lactate transporters, with use of LA as a surrogate marker of response.

Citation Format: Panagiotis J. Vlachostergios, Nirav Parikh, Katerina Oikonomou, Eugene Gibilaro, George Apergis. Elevated lactic acid is a negative prognostic factor in metastatic lung 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 4334. doi:10.1158/1538-7445.AM2015-4334
Abstract 435: Adipocyte-derived monocyte chemotactic protein-1 (MCP-1) promotes prostate cancer progression through matrix metalloproteinase (MMP-2) mediated extracellular matrix degradation
Authors: Ito Yusuke , Ishiguro Hitoshi , Kobayashi Naohito , Hasumi Hisashi , Watanabe Masatoshi , Yao Masahiro , Uemura Hiroji
Published: August 2015

Background: Obesity is known to be associated with prostate cancer development and progression, but the detailed mechanism is not clear. Monocyte chemotactic protein-1 (MCP-1) is secreted from cancer cells, stromal cells and adipocytes, and it is involved in prostate cancer progression. Here we investigated the biological role of MCP-1 secreted from adipocytes for prostate cancer cells.

Methods: Human pre-adipocytes (HPAds) were cultured and differentiated to mature adipocytes. Conditioned medium (CM) from HPAd cells was obtained using phenol red-free RPMI1640 medium. We performed a cytokine membrane array analysis to detect cytokines in the CM. To characterize the physiological function of MCP-1 in the CM, we performed an MTT-assay, a wound-healing and invasion assay with anti-MCP-1 antibody using three prostate cancer cell lines: DU145, LNCaP, and PC-3. Matrix metalloproteinase (MMP)-2 and MMP-9 activities were evaluated by gelatin zymography. A qPCR and Western blotting were used to examine the mRNA and protein expression levels of MMP-2.

Results: The cytokine membrane array of the CM showed a strong signal of MCP-1compared to the control medium, and we thus focused our attention on MCP-1 in the CM. The CM up-regulated the cancer cell proliferation, and the neutralization by anti-MCP-1 antibody inhibited the proliferative effect of the prostate cancer cell lines. The CM greatly increased the invasive activity in the prostate cancer cell lines, and anti-MCP-1 antibody decreased the invasiveness. Gelatin zymography revealed that the CM markedly enhanced the enzymatic activity of MMP-2, and anti-MCP-1 antibody down-regulated its effect. MMP-2 mRNA expression was undetected and the MMP-2 protein level was unchanged between the control medium and CM in DU145 cells.

Conclusions: MCP-1 from adipocytes enhances the growth and invasion activity of prostate cancer cells. The inhibition of MCP-1 derived from adipocytes might be an effective treatment for prostate cancer.

Citation Format: Yusuke Ito, Hitoshi Ishiguro, Naohito Kobayashi, Hisashi Hasumi, Masatoshi Watanabe, Masahiro Yao, Hiroji Uemura. Adipocyte-derived monocyte chemotactic protein-1 (MCP-1) promotes prostate cancer progression through matrix metalloproteinase (MMP-2) mediated extracellular matrix degradation. [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 435. doi:10.1158/1538-7445.AM2015-435
Abstract 4365: Targeting the SF3B1 spliceosome protein: Development of a reporter for HTS screen and pharmacodynamic profiling of small molecule drug leads
Authors: Shi Yihui , Lagisetti Chandraiah Lagisetti , Joyner Amanda S. , Sambucetti Lidia C. , Webb Thomas R.
Published: August 2015

The spliceosome is an important emerging target for cancer therapy that has only recently been uncovered that represents an exciting new opportunity for therapeutic intervention in cancer. Two naturally occurring bacterial products show striking selective toxicity to tumors and have recently been found to act by targeting the SF3b subunit of the spliceosome, thus modulating pre-mRNA splicing in tumor cells. However, these natural products, and analogs derived from them, are synthetically quite complex. We have designed and optimized a class of novel synthetic small molecules, called sudemycins, which also modulate alternative splicing and have substantial antitumor activity. Previous work in our lab has shown that our lead compound, sudemycin D6 has significant in vivo antitumor activity. We now report the development of a high-throughput cell-based luciferase reporter system that has multiple applications in facilitating splicing modulatory drug discovery and development.

Citation Format: Yihui Shi, Chandraiah Lagisetti Lagisetti, Amanda S. Joyner, Lidia C. Sambucetti, Thomas R. Webb. Targeting the SF3B1 spliceosome protein: Development of a reporter for HTS screen and pharmacodynamic profiling of small molecule drug leads. [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 4365. doi:10.1158/1538-7445.AM2015-4365
Abstract 4379: MPT0B292 enhances acetylation of α-tubulin through up-regulation of acetyltransferase gene, MEC-17 and exhibits potent anti-tumor, anti-angiogenesis and anti-metastatic effects in vitro and in vivo
Authors: Chang Jang-Yang , Cheng Yun-Ching
Published: August 2015

In recent years, epigenetic therapeutics is a new generation of chemotherapeutics for cancer. Microtubule-targeted agents constitute a type of anticancer drugs largely used in the clinics. Cells generate distinct microtubule subtypes through expression of different iso-types and through post-translational modifications, including acetylation, detyrosination, polyglutamination and polyglycylation. The acetylation of α-tubulin K-40 is controlled by the balance between acetyltransferase and de-acetylase expression. MEC-17, one of α-tubulin acetyltransferases, plays an important role in the regulation of acetylation of α-tubulin. Through screening of compounds that is able to selectively acetylate α-tubulin, MPT0B292 was identified.

Our results show that MPT0B292 up-regulate MEC-17 gene and protein expression, which subsequently lead to enhancing α-tubulin acetylation. MPT0B292 exhibits potent anti-proliferative activities toward various human cancer cells with IC50 ranged from 75 to 200 nM. In addition, HUVEC and WI-38 cells were much less susceptibility to the anti-proliferative effect of MPT0B292 with IC50 4 and12 μM, respectively. In FACS analysis of cell cycle, MPT0B292 induces G2/M phase arrest with concomitantly losses from G0/G1 and S phases in a concentration-dependent manner. Furthermore, MPT0B292 induces ROS generation in a concentration-dependent manner by FACS analysis, which leads to damaging mitochondria and triggering cell apoptosis. The effects MPT0B292-induced ROS and cell apoptosis could be significantly rescued by pretreatment with N-acetylcysteine, Diphenyleneiodonium (DPI) and rotenone. Moreover, the amount of ROS induced by MPT0B292 was significantly reduced by knockdown of MEC-17 with siRNA and resulted in rescuing cell viability. In addition, MPT0B292 inhibits cell motility by an increase in cellular focal adhesion area. Moreover, MPT0B292 shows potent activity against the growth of xenograft tumor of lung cancer cell, A549, without significantly compromising the mice body weight. MPT0B292 also decreases lung metastasis in orthotopical breast cancer model. These data indicate MPT0B292 is a promising anticancer compound with unique action of mechanism that has potential for future development.

Citation Format: Jang-Yang Chang, Yun-Ching Cheng. MPT0B292 enhances acetylation of α-tubulin through up-regulation of acetyltransferase gene, MEC-17 and exhibits potent anti-tumor, anti-angiogenesis and anti-metastatic effects in vitro and in vivo. [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 4379. doi:10.1158/1538-7445.AM2015-4379
Abstract 4387: Anti-tumor activity of TNF-gold nanodrugs tagged with tumor vasculature-homing peptides containing the NGR or isoDGR motives
Authors: Curnis Flavio , Gasparri AnnaMaria , Sacchi Angelina , Fiocchi Martina , Corti Angelo
Published: August 2015

Colloidal gold (Au) is a well-tolerated nanomaterial currently exploited for several applications in the field of nanomedicine. In particular, gold nanoparticles loaded with tumor necrosis factor-alpha (TNF), a cytokine endowed with anti tumor activity, have a therapeutic index higher than that of TNF. For this reason TNF-gold nanoparticles are currently tested in cancer patients.

We have addressed the hypothesis that TNF-gold nanoparticles tagged with tumor vasculature homing peptides have improved therapeutic properties.

To this aim we have tagged TNF-gold nanoparticles with albumin-peptide conjugates containing the NGR (Asn-Gly-Arg) or isoDGR (isoAsp-Gly-Arg) motives, i.e. with ligands of CD13 and integrin alphavbeta3, respectively, expressed by the tumor neovasculature.

The therapeutic properties of the resulting nanodrugs (called NGR-HSA/Au/TNF and isoDGR-HSA/Au/TNF) were then investigated in fibrosarcoma- or lymphoma-bearing mice and compared with those a nanodrug lacking the targeting peptide (called HSA/Au/TNF). The results showed that intravenous administration of extremely low doses of NGR-HSA/Au/TNF or isoDGR-HSA/Au/TNF (equivalent to 5 pg of bioactive TNF/mouse) were sufficient to induce anti-tumor effects, whereas similar doses of HSA/Au/TNF were minimally active. Low-dose NGR-HSA/Au/TNF and isoDGR-HSA/Au/TNF, but not HSA/Au/TNF, could also exert synergistic anti-tumor effects with melphalan, a chemotherapeutic drug. These findings support the concept that tagging TNF-gold nanoparticles with tumor vasculature homing peptides have an improved antitumor activity, likely because of an active targeting mechanism.

Citation Format: Flavio Curnis, AnnaMaria Gasparri, Angelina Sacchi, Martina Fiocchi, Angelo Corti. Anti-tumor activity of TNF-gold nanodrugs tagged with tumor vasculature-homing peptides containing the NGR or isoDGR motives. [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 4387. doi:10.1158/1538-7445.AM2015-4387
Abstract 4389: Liposomes containing piperazine compounds inhibit tumor growth in a patient-derived xenograft model of glioblastoma multiforme
Authors: Swindell Elden P. , Ugolkov Andrey , Freguia Christian , Dubrovskyi Oleksii , Hankins Patrick L. , Yang Jeong , Raizer Jeffrey J. , Chandler James P. , James Charles David , Mazar Andrew P. , O'Halloran Thomas V.
Published: August 2015

Glioblastoma multiforme (GBM) is fatal in nearly all instances, and responds poorly to current standards of care. GBMs exhibit resistance to chemotherapy which leads to tumor recurrence following initial surgical debulking. We have recently developed an 80 nm liposome containing a novel hydrophobic microtubule disrupting piperazine. This novel nanostructure, called IM-1 nanobin, contains 500-1000 piperazine drug molecules encapsulated in the hydrophobic inner leaflet of the lipid bilayer in each liposome. This nanoparticle inhibited the proliferation of GBM cells in vitro, although its cytotoxicity was reduced (3-5 fold) compared to free drug dissolved in DMSO. Results from FACS analysis showed that sub-micromolar concentrations of IM-1 caused G2/M phase cell cycle arrest and apoptosis of U87 GBM cells, as well as early passage GBM cells derived from a patient-derived xenograft (PDX). In collaboration with the Northwestern Brain Tumor Institute, we have established a panel of PDX. Since these tumors are not propagated in culture, they preserve the mixture of tumor cells and stroma critical for conducting meaningful therapy response experiments. IM-1 was evaluated in GBM PDX propagated in subcutaneous and intracranial compartments. In mice bearing subcutaneous PDX tumors, IM-1 treatment delayed the growth of the tumors compared to free drug alone; orthotopic GBM PDX studies are ongoing. Our results show that a novel liposome encapsulated piperazine, IM-1, is a promising new nanostructure for development as a therapeutic for treating patients with GBM.

Citation Format: Elden P. Swindell, Andrey Ugolkov, Christian Freguia, Oleksii Dubrovskyi, Patrick L. Hankins, Jeong Yang, Jeffrey J. Raizer, James P. Chandler, Charles David James, Andrew P. Mazar, Thomas V. O'Halloran. Liposomes containing piperazine compounds inhibit tumor growth in a patient-derived xenograft model of glioblastoma multiforme. [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 4389. doi:10.1158/1538-7445.AM2015-4389
Abstract 4394: Selective accumulation and specific tumor damage by folate receptor-targeted CA-4 prodrug as part of a combination of photodynamic therapy and site-specific chemotherapy
Authors: Gregory Nkepang , Bio Moses , Rajaptura Pallavi , Awuah Samuel G. , You Youngjae
Published: August 2015

A non-invasive or minimally invasive tumor ablation regimen is an attractive tool with which to control tumors. This approach is complementary to primary treatment options without causing systemic side effects or severe physical burdens from the treatment itself. Clinically approved photodynamic therapy (PDT) is one such regimen. In PDT, photosensitizers are activated by visible and near IR light to destroy tumors. However, the therapeutic efficacy of PDT is limited due to the spatial and temporal restrictions of the effector of PDT, singlet oxygen. We have been developing a new prodrug strategy that can overcome these limits by using a unique combination of PDT and site-specific chemotherapy. The prodrug is composed of photosensitizer and anticancer drug via a singlet oxygen-cleavable linker. Upon illumination, the prodrugs cause PDT damage and simultaneously release anticancer drugs only at the illuminated target area. In our previous publications, we reported 1) the design and synthesis of prodrugs of combretastatin A-4, 2) visible/ near IR light-controlled release of the drug from the prodrug, 3) bystander effects from the released anticancer drug, and 4) the superior antitumor effect of the prodrug compared to a simple combination of PDT and chemotherapy. Recently, a more advanced CA-4 prodrug was developed to achieve selective delivery to tumors via folate receptors (FRs) overexpressed in numerous cancer cell lines. The targeted prodrug showed FR-mediated uptake to FR-expressing cancer cells (colon 26 cells) in vitro and to FR-expressing tumors in vivo. Notably, the targeted CA-4 prodrug effectively ablated the tumors without causing collateral damage to the surrounding skin.

Citation Format: Nkepang Gregory, Moses Bio, Pallavi Rajaptura, Samuel G. Awuah, Youngjae You. Selective accumulation and specific tumor damage by folate receptor-targeted CA-4 prodrug as part of a combination of photodynamic therapy and site-specific chemotherapy. [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 4394. doi:10.1158/1538-7445.AM2015-4394
Abstract 440: Nicotinamide phosphoribosyltransferase (NAMPT): a new cytokine in tumor progression
Authors: Grolla Ambra , Torretta Simone , Amoruso Angela , Orsomando Giuseppe , Genazzani Armando
Published: August 2015

An important role has been shown for Nicotinamide phosphoribosyltransferase (NAMPT; also known as PBEF or visfatin) in cancer, inflammation and metabolic diseases. Alongside maintaining intracellular NAD levels constant by contributing to the salvage pathway of NAD production, it is now clear that NAMPT is also a pleiotropic player in cell signalling: (i) as a key regulator of NAD consuming-enzymes, including sirtuins and PARPs; and (ii) as an extracellular cytokine that binds to a yet unknown extracellular receptor. It has been shown that a regulated positive secretory process exists, although the exact mechanism of release is at present under investigation. A mounting amount of cell types have been shown to release eNAMPT, including adipocytes, hepatocytes, cardiomyocytes and activated immune cells.

In my work, I verified that eNAMPT is released by different types of tumour cells, specifically by melanoma, neuroblastoma and glioblastoma, mesotelioma, and prostate cancer cells in vitro. In particular, we analysed the mechanisms of its release and we found both classical and non-classical pathway involvement. eNAMPT release could be modulated by tumoural microenvironment conditions and once released by tumour cells, in our hands, eNAMPT has paracrine and autocrine effects: it activates MAPK and Akt pathways in melanoma cells and induces M1 polarization in human monocytes. Mainly, I demonstrated for the first time that eNAMPT levels in plasma of tumour-bearing mice are increased because part of this circulating protein derives directly from tumour itself. This parallels observations that eNAMPT is increased in cancer patients, and indeed this increase can be, at least, in part attributed to the tumour itself. All these data suggested that the tumour microenvironment might be enriched of this cytokine-like protein, which could have a role in tumour progression and severity.

Citation Format: Ambra Grolla, Simone Torretta, Angela Amoruso, Giuseppe Orsomando, Armando Genazzani. Nicotinamide phosphoribosyltransferase (NAMPT): a new cytokine in tumor progression. [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 440. doi:10.1158/1538-7445.AM2015-440
Abstract 4414: RhoA activation in diffuse type gastric adenocarcinoma promotes cancer stem cell phenotypes including chemotherapy resistance
Authors: Yoon Changhwan , Cho Soo-Jeong , Aksoy Bulent A. , Park Do Joong , Yoon Sam S.
Published: August 2015

Introduction: The diffuse type of gastric adenocarcinoma (GA) was recently found to frequently harbor activating mutations in RHOA. RhoA is a member of the small GTPase-Ras-like proteins which are involved in cell signaling for cell migration and cell cycle.

Methods: RhoA activity and inhibition was examined in diffuse GA cell lines grown as spheroids (i.e. cancer stem cell conditions) and as monolayers in various in vitro assays. RhoA knockdown combined with chemotherapy was examined in a mouse xenograft model.

Results: RhoA activity was much higher in diffuse GA cell lines MKN-45 and SNU-668 compared to intestinal GA cell lines NCI-N87 and AGS. RhoA activity was further increased in diffuse GA cells when grown as spheroids rather than as monolayers. RhoA inhibition with shRNA or the RhoA inhibitor Rhosin decreased spheroid formation and deceased expression of the stem cell transcription factor, Sox2. Diffuse GA cells when grown as spheroids had significantly greater migration, invasion, and anchorage-independent growth, and these properties could all be blocked with RhoA shRNA or Rhosin. Diffuse GA spheroid cells (compared to monolayer cells) were resistant to 5-fluorouracil and cisplatin chemotherapy, and this chemotherapy resistance could be reversed with RhoA inhibition. In the MKN-45 xenograft model, cisplatin inhibited tumor growth by 50%, RhoA shRNA by 60%, and the combination by 83%. Clinical tumor samples of diffuse GA are currently being analyzed for RhoA expression and correlated with extent of disease and response to chemotherapy.

Conclusions: RhoA signaling is upregulated in diffuse GA cells grown as spheroids and promotes malignant transformation phenotypes such as migration and invasion. RhoA inhibition can reverse chemotherapy resistance in GC spheroid cells and in tumor xenografts, and thus the RhoA pathway is a promising new target of therapy for diffuse GA.

Citation Format: Changhwan Yoon, Soo-Jeong Cho, Bulent A. Aksoy, Do Joong Park, Sam S. Yoon. RhoA activation in diffuse type gastric adenocarcinoma promotes cancer stem cell phenotypes including chemotherapy resistance. [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 4414. doi:10.1158/1538-7445.AM2015-4414
Abstract 4443: PB-42: Design and characterization of a glutathione pro-drug selectively delivered to normal tissue and not tumor tissue
Authors: Thomas James P. , Geiger Peter G.
Published: August 2015

The vast majority of cancer treatment regimens involve cytotoxic chemotherapy or radiation with a narrow therapeutic index. More than ½ of all approved anticancer drugs are associated with generation of reactive oxygen species. We have developed a molecule that selectively increases glutathione in normal tissues while not protecting cancer cells. Our compound has a backbone of the glutathione (GSH) precursor γ-glutamyl cysteine, with each acid group protected by ethyl ester moieties. The PB-42 molecule then leverages the dramatic differences in endothelial alkaline phosphatase between normal and cancerous tissues, similar to amifostine. Selectivity is based on a phosphorothioate moiety that requires activation by alkaline phosphatase. We have developed a robust, scalable synthetic pathway for PB-42. Cultured cells incubated with PB-42 dramatically increase intracellular GSH and total nonprotein sulfhydral (NPSH) levels several fold over controls. This process is totally dependent on activation with alkaline phosphatase. Increased GSH and NPSH levels translate into dramatic resistance to the cytotoxic effects of common chemotherapeutic agents such as cisplatin or melphalan. GSH increases are not inhibited by prior incubation with the γ-glutamyl cysteine synthase inhibitor buthionine sulfoximine (BSO), demonstrating that PB-42 enters into the GSH synthetic pathway beyond the allosterically controlled step and is not simply providing intracellular cysteine. Cells initially depleted of endogenous GSH with BSO demonstrated dramatic increases in GSH after co-incubation with PB-42 and alkaline phosphatase. PB-42 was well tolerated in vivo and was able to abrogate cisplatin-induced nephrotoxicity. PB-42 could offer several advantages in selective protection against the toxic effects of chemotherapy and radiation therapy as compared to amifostine, in that it generates the natural sulfhydral GSH, that in addition to acting as a bulk thiol, also participates in a number of enzyme based protective systems.

Note: This abstract was not presented at the meeting.

Citation Format: James P. Thomas, Peter G. Geiger. PB-42: Design and characterization of a glutathione pro-drug selectively delivered to normal tissue and not tumor tissue. [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 4443. doi:10.1158/1538-7445.AM2015-4443