bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 3735: Increased efficacy with use of combination therapy of API 31510 and gemcitabine in the treatment of pancreatic cancer
Authors: Narain Niven R. , Sarangarajan Rangaprasad , Ouro-Djobo Rakib , Bourdelais Justin J. , Grund Eric , Vishnudas Vivek , Mauro Lucia M. , Lens Assuan , Yunis Adel , Agarwal Shuili , Song Paul Y. , McCook John P. , Jimenez Joaquin J.
Published: August 2012

Pancreatic Carcinoma is one of the deadliest types of cancers and certainly one that is most clinically difficult to manage given that most diagnoses occur in late-stage disease. Gemcitabine is among the few FDA approved drugs used alone and in combination with other antineoplastic agents for pancreatic cancer. API 31510, a novel intravenous formulation of Ubidecarone, induced superior cell death kinetics in pancreatic carcinoma cell line, MiaPaca alone or in combination with gemcitabine. In addition, the study employed an in vivo model of pancreatic cancer to assess the translation of the cell-based data of combination gemcitabine and API 31510. Animals were randomized into 4 groups of 30 rats each; group 1 received no treatment, group 2 received gemcitabine (150 mg/kg weekly for 3 weeks with one week rest), group 3 were injected with API 31510 (50 mg/kg daily), and group 4 received a combination of daily API 31510 (50kg/mg) and gemcitabine at the aforementioned regimen. The untreated group exhibited steep death rates, whereas in API 31510, gemcitabine alone and the combination of API 31510 resulted in prolongation of life. API 31510 alone had significantly greater impact than gemcitabine alone. Animals treated with gemcitabine + API 31510 exhibited prolonged survival and elicited long-term remission that was statistically significant compared to other groups. In addition, palpable tumors were decreased in the groups treated with API 31510, and to a greater degree, in those treated with gemcitabine in combination with API 31510. It is noteworthy that tumor histology demonstrated a hallmark disruption in tumor vasculature with use if API 31510. Taken together, these findings suggest that API 31510 offers a new approach to treatment and management of pancreatic cancer alone and combination with established chemotherapy regimens that include gemcitabine.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3735. doi:1538-7445.AM2012-3735
Abstract 3736: The mTOR inhibitor, RAD001, displays higher cytotoxicity in leukemias with hyperactivated PI3K/AKT/mTOR pathway
Authors: Cani Alice , Simioni Carolina , Capitani Silvano , Martelli Alberto M. , Neri Luca M.
Published: August 2012

Acute myelogenous leukemia (AML) is a disease resulting from the clonal expansion and accumulation of hematopoietic stem cells arrested at various stages of development. B-cell Acute lymphoblastic leukemia (B-ALL) is a form of leukemia characterized by lymphoblast abnormal increase. B-ALL is the most common form of cancer in childhood with a peak of incidence at 2-5 years of age, and another peak in the elderly. The overall cure rate in children is about 80%, and about 38% to 60% of adults have long-term disease-free survival. Although the prognosis of AML and ALL has improved in the last decades, the outcome of relapsed and chemoresistant AML and ALL is still poor, especially in adults, with only a 35-40% survival at 5 years. Therefore, major efforts are being made to develop rationally targeted therapies against alterated signaling cascades that sustain AML and ALL cell proliferation, survival, and drug-resistance. A signaling pathway that is frequently upregulated in AML and ALL is the PI3K/Akt/mTOR network. To explore whether this pathway could represent a potential pharmacological target in AML and ALL, we evaluated the effects of the mTOR inhibitor, RAD001, on the HL60 AML cell line and on the SEM B-ALL cell line.RAD001decreased viability in AML and ALL cell lines, as demonstrated by MTT experiments. The values of IC50 at 24 and 48 hours in HL60 cell line was 8μM, while in SEM cell line, that displays an hyperactivation of the PI3K/Akt/mTOR pathway, the IC50 range was from 4,7 to 6,8 μM, thus showing an higher sensitivity of this cell line to this targeted therapy. As documented by Western Blotting, RAD001 showed a concentration-dependent induction of apoptosis with a relevant increment of PARP, Caspase 3, 8 and 9 cleavage in both cell lines. The ALL cell line SEM, with hyperactivated PI3K/Akt/mTOR pathway, displayed a much higher Caspase and PARP cleavage dependent apoptosis.PI3K/Akt/mTOR downstream targets were also partially dephosphorylated by RAD001, in particular GSK3β and 4E-BP1. RAD001 induced no significant changes in Akt dephosphorylation in HL60 and SEM cell lines, and this is in agreement with several reports showing no relevant changes in the phosphorylation of Akt. The cells always expressed unchanged total Akt. This indicates that PI3K/Akt/mTOR inhibition could be an attractive target to develop innovative therapeutic strategies directed towards AML and ALL leukemia cells.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3736. doi:1538-7445.AM2012-3736
Abstract 374: Development of tumor-targeted near infrared dyes for fluorescence guided surgery
Authors: Kelderhouse Lindsay E. , Chelvam Venkatesh , Wayua Charity , Sakkarapalayam Mahalingam M. , Poh Scott , Kularatne Sumith A. , Low Philip S.
Published: August 2012

Surgical resection of malignant disease is currently one of the most common and effective cancer treatments. Unfortunately, quantitative tumor resection is limited by a surgeon's ability to distinguish diseased tissue from adjacent healthy tissue. Fluorescence guided surgery has emerged as a tool to aid surgeons in the identification and removal of malignant tissue. While non-targeted fluorescent dyes injected near the primary tumor mass have been shown to passively accumulate in tumors and lymph nodes, the resulting tumor to background ratios are often poor and boundaries between malignant and normal tissue difficult to define. To circumvent these problems, our lab has developed high affinity tumor-specific ligands that can bind to either the prostate specific membrane antigen (PSMA) or the folate receptor (FR); i.e. cell surface molecules that are over-expressed on a number of cancers. In this study, we link these tumor targeting ligands to near infrared (NIR) dyes and explore their use in fluorescence guided surgery. In vitro, all FR and PSMA targeted NIR dyes were found to have binding affinities in the low nanomolar range. Binding was quantitatively blocked with 100-fold excess of free ligand. Upon injection into mice with metastatic disease, the targeted NIR dyes allowed clear distinction of tumor tissue from adjacent healthy tissue. Surgical resection could be conducted until all fluorescent tissue was removed. All resected fluorescent lesions were later confirmed by histology to be malignant. Of the NIR dyes tested, the 800 nm dyes were found to have the greatest fluorescence intensity through porcine tissue, indicating their superior ability to reveal buried tumor nodules. Collectively, these tumor-specific NIR dyes demonstrate significant potential for use in fluorescent guided surgery by aiding in the complete resection of diseased tissue.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 374. doi:1538-7445.AM2012-374
Abstract 3744: Antitumor activity of CUDC-907, a dual PI3K and HDAC inhibitor, in hematological cancer models
Authors: Rudi Bao , Wang Dagong , Qu Hui , Yin Ling , Zifcak Brian , DellaRocca Steven , Xu Guang-Xin , Borek Mylissa , Samson Maria , Atoyan Ruzanna , Poli Anne , Wang Jing , Zhai Hai-Xaio , Lai Cheng-Jung , Pepicelli Carmen , Cai Xiong , Qian Changgeng
Published: August 2012

Recent evidence indicates that both PI3K-Akt-mTOR signaling pathway and HDAC are validated targets in hematological cancers. In order to overcome primary resistance and prevent secondary resistance resulting from compensatory/feedback mechanisms in cancer cells, CUDC-907 was designed to inhibit all isoforms of Class I PI3K and Class I and II HDAC, based on previous observations that synergistic effects can be achieved by inhibition of both HDAC and PI3K in cancer cells. In cell proliferation assays, this compound displays potent anti-proliferation activity in hematological cancer cell lines including non-Hodgkin's lymphoma (NHL), and multiple myeloma (MM). Mechanistically, CUDC-907 is able to simultaneously suppress PI3K-Akt-mTOR as well as other essential signaling pathways due to epigenetic modifications via HDAC inhibition. CUDC-907 is orally bio-available in dogs, has a long half-life in murine tumors, induces apoptosis and inhibits cancer cell proliferation in xenograft tumors. In efficacy studies in NHL and MM models, CUDC-907 is more efficacious than either a single-agent PI3K or HDAC inhibitor reference compound or a combination of the two agents given at maximally tolerated doses (MTD). Furthermore, CUDC-907 is more efficacious than the PI3Kα-selective inhibitor CAL-101 when dosed at MTD doses. These observations are related to our findings that, all isoforms of PI3K are expressed in most hematological cancer models. Therefore, the efficacy of isoform selective PI3K inhibitors may be limited only to those cancers driven by a specific PI3K subtype. In addition, a synergistic antitumor effect can be achieved in efficacy studies when CUDC-907 is combined with standard of care agents in both NHL and MM models. In conclusion, through broad network disruption, CUDC-907 may offer a greater therapeutic benefit than isoform-specific PI3K inhibitors as a novel anti-cancer treatment of hematological malignancies.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3744. doi:1538-7445.AM2012-3744
Abstract 3757: CR8, a novel CDK inhibitor, enhances vandetanib activity in a human medullary thyroid carcinoma model
Authors: Broutin Sophie , Hervé-Bazin Morgane , Commo Frédéric , Oumata Nassima , Meijer Laurent , Dupuy Corinne , Schlumberger Martin , Bidart Jean-Michel
Published: August 2012

Introduction: CR8 (ManRos Therapeutics) is a novel inhibitor of cyclin-dependent kinases (CDKs) that selectively targets CDK1/2/3/5/7/9. CDK inhibitors have already shown potent antitumoral activity. Recently, vandetanib (Astra Zeneca), a tyrosine-kinase inhibitor, was approved in the U.S. for the treatment of adult patients with metastatic Medullary Thyroid Carcinoma (MTC). The absence of complete tumor responses justifies the development of new therapeutic options. The aim of this study was to investigate the preclinical activity of CR8 alone and in combination with vandetanib in a MTC model. Materials and Methods: The human MTC TT cell line, bearing a RETC634W activating mutation, was cultured in the absence or the presence of CR8 (10-10 000 nM) and/or vandetanib over 6 days. Cell proliferation was assessed by WST-1 assay. Activation of RET, PP1α and oncogenic pathways (PI3K/AKT, MEK/p44-42) was analyzed by western-immunoblotting. Calcitonin secretion in cell culture media was measured by ELISA. Results: Both CR8 and vandetanib when used alone strongly inhibit TT cell proliferation at day 3 of treatment. Addition of CR8 (10 nM) enhances the antiproliferative activity of low vandetanib concentrations. As expected, vandetanib alone inhibits RET, MAPK and AKT phosphorylation and CR8 inhibits PP1α. Interestingly, CR8 alone induces activation of RET, MAPK and AKT phosphorylation, and the addition of vandetanib (>100 nM) inhibits RET signalling pathways. At day 3 of treatment, vandetanib (>100 nM) and CR8 (100 nM) reduced and induced calcitonin secretion, respectively. Conclusion: CR8 displays an antiproliferative effect on TT cells and enhances the antiproliferative activity of vandetanib. CR8 acts by inhibiting PP1α and, surprisingly, induces an activation of RET and stimulates calcitonin production. These results suggest that the combination of vandetanib with CDKs inhibitors such as CR8 may be of value to improve therapeutic response.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3757. doi:1538-7445.AM2012-3757
Abstract 3768: Evaluating the effects of bortezomib (Velcade®) on the pharmacokinetics (PK) of pegylated liposomal doxorubicin (Doxil®, PLD)
Authors: La-Beck Ninh M. , Walko Christine M. , Scoggins Lakia , Dees E. Claire , Orlowski Robert Z. , Wu Huali , Amantea Michael , Fardin Mahsa , Zamboni William
Published: August 2012

Background: PLD is a pegylated liposomal formulation of doxorubicin approved for the treatment of ovarian cancer, Kaposi's sarcoma, and multiple myeloma. We have reported that age, gender, and monocyte count may affect the clearance (CL) of PLD. In multiple myeloma, PLD is used with bortezomib, a proteosome inhibitor which can affect monocyte count. The purpose of this cross study comparison was to assess the effects of bortezomib on the CL of PLD. Methods: This was a cross trial comparison of patients with solid tumors who received PLD alone and PLD + bortezomib. The PLD alone group (n = 34) received PLD at 10 to 60 mg/m2 IV every 28 days. The PLD + bortezomib group (n = 25) received bortezomib at 0.90 to 1.50 mg/m2 IV on days 1, 4, 8, and 11, and PLD at 30 mg/m2 IV on day 4, every 21 days. PK studies of PLD were performed for cycle 1, after administration of PLD alone and PLD + bortezomib. Serial blood samples were obtained from 0 to 96 h and from 7 to 28 days after administration of PLD. Plasma samples were processed to measure sum total (encapsulated + released) doxorubicin via HPLC and the clearance (CL) was calculated with WinNonlin using noncompartmental methods. Results: In patients < 60 years old, the mean (± standard deviation) PLD CL after administration of PLD alone and in combination with bortezomib was 63.4 (± 46.1) and 23.3 (± 7.6) mL/h, respectively (P=0.017). In patients >= 60 years old, the PLD CL after administration of PLD alone and in combination with bortezomib was 39.1 (± 18.5) and 38.0 (± 15.5) mL/h, respectively (P>0.05). In male patients, the PLD CL after administration of PLD alone and in combination with bortezomib was 65.4 (± 33.4) and 38.4 (± 9.7) mL/h respectively (p>0.05). In female patients, the PLD CL after administration of PLD alone and in combination with bortezomib was 40.1 (± 33.4) and 24.6 (± 11.2) mL/h respectively (P>0.05). Conclusion: This cross study comparison suggests that bortezomib decreases PLD CL in younger patients and in male patients. Although the underlying mechanism for this effect on PLD CL is not known, it may be related to bortezomib inhibition of mononuclear phagocyte activity in certain patient populations, which is responsible for the CL of PLD. There is a need to further investigate this in a prospective drug interaction study.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3768. doi:1538-7445.AM2012-3768
Abstract 3773: Absolute bioavailability of BRAF inhibitor GSK2118436: Use of a microtracer study in patients with cancer
Authors: Denton Cathrine L. , Carson Stanley W. , Young Graeme C. , Richards-Peterson Lauren E. , Botbyl Jeffrey , Morrison Royce A. , Blackman Samuel C. , Ouellet Daniele
Published: August 2012

Background. Absolute bioavailability (BA) studies in oncology are logistically and technically challenging. Use of an intravenous (IV) microtracer offers an attractive alternative to conventional cross-over design studies. This method involves concomitant administration of a non-labeled oral therapeutic dose with a radiolabeled IV microtracer dose. Advantages include: 1) fewer subjects required as comparisons are within-subject and within-period, yielding reduced variability; 2) easier development of IV formulation for drugs with low solubility (microtracer doses are ≤ 100 μg); 3) radioactivity doses are low and do not require special handling (usually ≤ 270 nCi of 14C) and 4) negligible toxicity, as the contribution of the microtracer dose to overall exposure is typically < 0.5% of the oral dose. The approach required development of an ultra-sensitive assay using accelerator mass spectrometry (AMS) to determine pharmacokinetic (PK) parameters from IV dosing. The purpose of this study was to determine absolute BA for the BRAF inhibitor GSK2118436 in cancer patients. Methods. Patients with BRAF-mutant solid tumors were enrolled in an open-label, non-randomized study. Patients received a single oral dose of GSK2118436 (150 mg capsule) followed by a 15-min microtracer infusion (50 μg [14C] GSK2118436), started 1.75 h after the oral dose to coincide with oral Tmax. Plasma samples were collected at timed intervals up to 72 h post-oral dose. Total radioactivity and [14C] GSK2118436 were measured by AMS. Non-labeled GSK2118436 was measured by LC-MS/MS. PK parameters were calculated using standard non-compartmental methods. Results. Preliminary PK parameters were determined in 4 subjects (Table). Absolute BA, expressed as least squares mean (90% CI), was 84.2% (72.3-98.1). Conclusions. The absolute BA of oral GSK2118436 was high. This innovative IV microtracer study was an efficient and accurate way to determine absolute BA of GSK2118436 in patients with advanced cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3773. doi:1538-7445.AM2012-3773
Abstract 3784: AME-133v, a humanized, Fc-engineered anti-CD20 monoclonal antibody, demonstrates greater B cell depletion than Rituxan in vitro
Authors: Wayne Jennifer L. , Campbell Mary-Ann , Marulappa Shashi , Jain Vinay
Published: August 2012

Purpose The efficacy of AME-133v in depleting B lymphocytes was compared in vitro to that of Rituxan, and the effect of FcαRIII genotype was assessed. Methods Blood samples from 37 healthy donors were collected and genotyped for FcαRIII polymorphism. Varying concentrations of AME-133v or Rituxan were applied to samples and CD19+ peripheral circulating B lymphocytes were measured using fluorescence-activated cell sorting (FACS). B cell depletion was listed as a percentage of baseline level. Results In an in vitro whole blood assay, AME-133v was more effective in depleting B lymphocytes from baseline levels than Rituxan, particularly at increasing concentrations (Table 1). Significant differences were found between treatments averaged over doses, between doses averaged over treatments, and between treatments depending on dose, all with p<0.0001. AME-133v's superior effect in depleting B cells is independent of dose (p<0.001), but caused greater B cell depletion at lower concentrations of antibody. In both AME-133v and Rituxan treatments, VF and FF patients demonstrated less B cell depletion, corroborating previous data citing decreased response to Rituxan among F-carriers and indicating improved pharmacodynamics of AME-133v. Conclusion AME-133v is engineered for a 6-fold more potent effector function in antibody-dependent cell-mediated cytotoxicity (ADCC) compared to Rituxan, which is elucidated through improved B cell depletion, across doses. Depletion in AME-133v-treated patients was also greater across all genotypes, suggesting superior pharmacodynamics of AME-133v in the low-responding F-carrier population. These findings indicate relevant biological activity of the antibody and suggest that AME-133v may provide additional clinical benefit for low-affinity FcαRIII patients. A randomized trial is being planned to compare clinical efficacy of AME-133v vs. Rituxan, targeting low-affinity FcαRIII patients.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3784. doi:1538-7445.AM2012-3784
Abstract 3809: Effects of honokiol on UACC-62 and SKMEL-2 melanoma cell lines
Authors: Guillermo Ruth F. , Stevens Jonathan M. , Kaushik Radhey S. , Young Alan , Zeman David , Dwivedi Chandradhar
Published: August 2012

Honokiol is a plant lignan extracted from the magnolia bark tree, previous studies from our laboratory showed its chemopreventive effects in a UVB-induced skin cancer model, as well as pro-apoptotic effects in A431 squamous cancer cell line. Studies from other groups have reported antineoplastic effects in different cancer models as well. In this study, the antineoplastic effects of honokiol were evaluated in vivo and in vitro against UACC-62 cell line that harbors mutated BRAF, CDK4i, PTEN and against SKMEL-2 cell line that presents NRAF, and TP53 mutated genes. For the in vivo studies, nude male mice were injected subcutaneously with 5x106 UACC-62 or SKMEL-2 cells. The next day animals were randomized into control and treatment groups, each group containing 20 animals. The control group received 250 αl of sesame oil intraperitoneally (IP), the treatment groups received honokiol dissolved in sesame oil; 1.25 mg (IP) in the UACC-62 group and 50 mg/kg (IP) in the SKMEL-2 injected mice. Animals were treated three times a week, for 5-7 weeks. Tumors’ incidence, multiplicity and volume were recorded every three days, mice's weights and external signs of toxicity were also closely monitored. Tumor tissues were collected for histopathology, Western blots, and PCR arrays. For the in vitro studies, both cell lines were evaluated for cell viability, proliferation, apoptosis by TUNEL assay, cell cycle arrest by propidium iodide staining, and Western blots for proteins expressions. Honokiol treatment significantly reduced (p<0.05) tumor volumes in both xenograft experiments. No evident signs of toxicity were observed in the honokiol treated animals. In both cell lines, honokiol significantly decreased (p<0.05) cell viability and proliferation, honokiol caused cell cycle arrest in Go/G1 phase in UACC-62 cell line, while it caused accumulation of cells in the G2/M phase in SKMEL-2 cell line; honokiol significantly increased the DNA fragmentation in both cell lines. Honokiol strongly decreased the expressions of cyclin D1, cyclin D2 and cyclin B1 while increasing the cleavage of caspase 3, caspase 8, caspase 9 and PARP in both cell lines. In UACC-62 honokiol decreased the expressions of CDK2, CDK4, cyclin E, cdc2p34 and p21. In SKMEL-2, honokiol decreased the expression of CDK4, PCNA and increased the expression of p21. These findings suggest that honokiol is a good candidate for further studies as a treatment for malignant melanoma. This work is supported by a Translational Cancer Center Research Grant, funded as 2010 Research Initiative Center by the State of South Dakota.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3809. doi:1538-7445.AM2012-3809
Abstract 3817: Nitric oxide-donating aspirin induces G2/M phase cell cycle arrest in human cancer cells by regulating phase transition proteins
Authors: Gao Li , Williams Jennie L.
Published: August 2012

NO-aspirin (NO-ASA), consisting of aspirin, a non-steroidal anti-inflammatory drug (NSAID), and a nitric oxide (NO)-releasing group, is reportedly safer than aspirin and effective in colon cancer chemoprevention. NO-ASA reduced the growth of several cancer cell lines much more potently than aspirin, with IC50 values at 24-h as follows: (a) colon (HT-29, SW480, HCT-15, and LoVo) 174 to 257 µM; (b) pancreas (BxPC-3), 175 µM; (c) skin (A431), 133 µM; (d) cervix (Hela), 240 µM; and (e) breast (MCF-7), 268 µM. In all instances, the IC50 values for the parent compound were >1,000 µM. To assess NO-ASA's mechanism of action, we studied in vitro its effect on colonocyte kinetics. In all cell lines examined, the growth inhibitory effect of NO-ASA was accompanied by cell cycle arrest in the G2/M phase transition. This inhibition directly correlated to altered expression of G2/M transition related proteins. Specifically, NO-ASA had a time- and concentration-dependent effect on the expression of cyclin D1. Here we propose that NO-ASA-mediated G2/M arrest is probably caused by ROS generation. This conclusion is based on (a) treatment with NO-ASA generates ROS in SW480 and (b) the G2/M arrest induced by NO-ASA is abolished on pretreatment with the antioxidant NAC. Thus, NO-ASA's superior effectiveness compared to traditional aspirin is due in part to its ability to induce G2/M phase cell cycle arrest in human cancer cells.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3817. doi:1538-7445.AM2012-3817
Abstract 3836: Enhancement of doxorubicin cytotoxicity in breast cancer by NIM811, A non-immunosuppressive cyclosporine A analog
Authors: Zeng Xianke , Zheng Jiamao , Feeney Y'vonne , Harrington Katie , Clevenger Charles
Published: August 2012

Cyclophilin A (CypA) is a member of the immunophilin family of peptidyl prolyl isomerases (PPI) that catalyze the cis-trans interconversion of proline imide bonds of peptides. In this role, cyclophilins have been found to function as signaling switches, regulating the activity of receptors, kinases and transcription factors. The PPI activity of CypA is inhibited by the immunosuppressive drug cyclosporine A (CsA), and in turn the CypA-CsA complex inhibits calcineurin-mediated NFAT activation. Our laboratory has demonstrated that CypA is necessary for the prolactin (PRL)-induced activation of Jak2/Stat5 signaling and gene expression (Cancer Res 68:7769, 2008). In addition, we have also shown that CsA inhibits the in vitro and in vivo growth and progression of both ER+ and ER- breast cancer cell lines. Here, we show that the non-immunosuppressive CsA analog NIM811 blocked PRL-stimulated activation of the Jak2/Stat5, PI3K/AKT and MAPK pathways in T47D cells. NIM811 also inhibited ER+, ER-, and Her2+ breast cancer cell proliferation, survival, motility and anchorage independent growth in a dose-dependent manner. NIM811 inhibited PRL induced gene expression, such as CISH and Cyclin D1. NIM811 also blocked the PRL-induced association between Stat5 and cMyb, and at higher doses, triggered PARP cleavage and activate Caspase 3. Furthermore, NIM811 increased the effects of doxorubicin in inhibiting monolayer cell growth and soft agar colony growth in vitro. In vivo, NIM811 alone significantly induced the primary tumor central necrosis and inhibited lymph node metastasis; combining NIM811 with a low dose of doxorubicin significantly inhibited MDA-MB-231 breast cancer xenograft tumor growth and distant organ metastasis. In summary, these results indicate that non-immunosuppressive cyclophilin inhibitor NIM811 has significant potential as both a single agent or in combination with cytotoxic agents for breast cancer therapy.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3836. doi:1538-7445.AM2012-3836
Abstract 3991: Protein phosphatase 2A (PP2A) downregulation is associated with androgen-independent and aggressive phenotypes in prostate cancer
Authors: Bhardwaj Arun , Srivastava Sanjeev K. , Singh Seema , Arora Sumit , Honkanen Richard E. , Grizzle William E. , Reed Eddie , Singh Ajay P.
Published: August 2012

First line of therapy for advanced prostate cancer (PCa) is androgen-deprivation through surgical or chemical castration; however, in majority of cases, tumors relapse in an androgen-independent (AI) form. Once the PCa has recurred in AI form, it progresses to a highly aggressive disease with frequent metastasis and poses an increased risk of morbidity and death. Previously, we demonstrated that PPP2CA, which encodes for alpha-isoform of the protein phosphatase 2A (PP2A) catalytic subunit, is downregulated in prostate cancer. Furthermore, we showed that PP2A activity is inversely associated with AI growth of PCa cells through a novel mechanism, whereby loss of PP2A-mediated checkpoints leads to the activation of Akt and ERK and partially sustains androgen receptor (AR) signaling under steroid-deprived condition. Since AI phenotype of PCa is associated with enhanced metastatic potential, we have investigated, in this study, a role of PPP2CA in the aggressive behavior of the PCa cells. For this, we overexpressed PPP2CA in AI (C4-2 and PC-3) PCa cells, while silenced its expression in AD (LNCaP) PCa cells. We observed that overexpression of PPP2CA in C4-2 and PC-3 cells not only decreased their AI growth and clonogenic ability, but also led to reduced motility and invasion and enhanced cell-cell interaction. Conversely, we observed increased cell motility and invasion and decreased cell-cell interaction upon PPP2CA silencing in LNCaP cells. Immunoblot analyses demonstrated gain of epithelial and loss of mesenchymal markers in PPP2CA-overexpressing PCa cells or vice versa indicating a role of PP2A in opposing epithelial to mesenchymal transition (EMT). Altogether, these studies provide evidence for a functional role of PPP2CA in aggressive behavior of AI PCa cells.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3991. doi:1538-7445.AM2012-3991
Abstract 3997: TUSC3 (N33) affects protein N-glycosylation and proliferation of prostate cancer cells
Authors: Horak Peter , Tomasich Erwin , Anees Mariam , Marhold Maximilian , Gerschpacher Marion , Pils Dietmar , Krainer Michael
Published: August 2012

Prostate cancer is the most prevalent cancer in males in developed countries. Molecular aberrations in the pathogenesis of this disease are numerous, though losses on the short arm of chromosome 8 are highly prevalent. In our previous studies, hypermethylation and diminished TUSC3 expression turned out to be significantly associated with poor progression free and overall survival in ovarian cancer. Additionally, expression profiling of TUSC3 negative cancer cell lines revealed deregulation of genes involved in ‘cell structure and motility’ and ‘development processes’, further supporting our hypothesis of TUSC3 as a tumor suppressor. In silico prediction of TUSC3 shows a high homology of TUSC3 to the Ost3p subunit of the oligosaccharyltransferase (OST) complex in yeast, hinting to its role in protein glycosylation. In this project, we characterized TUSC3 (N33), a putative tumor suppressor gene on 8p, in prostate cancer. To study the prognostic role of TUSC3 in prostate cancer we used a comprehensive prostate cancer tissue microarray, comprised of samples from 143 prostate cancer patients. Serum DNA methylation was studied in an additional cohort of 67 prostate cancer patients. Statistical analysis demonstrated low or missing TUSC3 protein expression in 56.6% of prostate cancer patients based on immunohistochemical staining. Methylation of the TUSC3 promoter was observed in 38.8% of prostate cancer patients’ serum DNA, confirming our previous findings of TUSC3 promoter hypermethylation as a possible epigenetic regulatory mechanism. In our prostate cancer cohorts, however, neither expression nor hypermethylation of TUSC3 had a significant effect on overall survival, possibly due to the relatively short follow-up period. Next, we studied the function of TUSC3 in N-glycosylation and in particular its influence on carcinogenesis using a cell culture model. We downregulated TUSC3 expression in prostate cancer cell lines DU145 and PC3 using shRNA mediated knockdown and analyzed them for their proliferative and carcinogenic properties in vitro. We could show that loss of TUSC3 expression confers growth advantage of prostate cancer cell lines, in particular under conditions of serum starvation. We also observed increased migratory properties of prostate cancer cell lines upon TUSC3 knockdown. Further, influence of TUSC3 downregulation on several putative targets of N-linked glycosylation has been analyzed in vitro. In our study, we characterized TUSC3 expression and/or methylation in prostate cancer patients and obtained a first mechanistic insight into its function in N-glycosylation and carcinogenesis.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3997. doi:1538-7445.AM2012-3997
Abstract 4002: Functional investigation and identification of dephosphorylation targets of tumor-suppressive protein tyrosine phosphatase, PTPRG
Authors: Cheung Arthur KL , Lung Hong Lok , Ko Josephine MY , Ip Joseph CY , Zabarovsky Eugene , Stanbridge Eric J. , Lung Maria L.
Published: August 2012

Background and aims: PTPRG was identified as a candidate tumor suppressor gene. It belongs to a family of membrane-bound receptor tyrosine phosphatases. However, the function and the dephosphorylation targets of PTPRG still remain to be elucidated. The aim of this current study was to identify the downstream dephosphorylation targets of PTPRG. Methods: A tetracycline-inducible system was used to obtain PTPRG-expressing clones. The dephosphorylation targets were identified by an antibody array. The anti-angiogenesis function of PTPRG was investigated by HUVEC tube formation assay. Results: The c-jun phosphorylation level was found to be down-regulated after re-expression of PTPRG. Re-expression of PTPRG can inhibit tube formation in the HUVEC tube formation assay by down-regulating the AP1 downstream target, VEGF, secretion. Conclusions: Re-expression of PTPRG can reduce the phosphorylation of c-jun and, thus, inhibit angiogenesis by down-regulating the important angiogenesis regulator, VEGF. The results suggest the importance of PTPRG in regulating tumor formation. It is a good candidate tumor suppressor gene, which warrants further study. Acknowledgements: This work was supported by the Research Grants Council and the University Grants Council of the Hong Kong Special Administrative Region, People's Republic of China (AoE/M-06/08, to M.L.L.) and the University of Hong Kong Small Project Fund (Grant 200907176081, to A.K.L.C.).

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4002. doi:1538-7445.AM2012-4002
Abstract 4005: Active SHP2 mutant induces lung hyperproliferative lesions and adenoma in transgenic mice
Authors: Schneeberger Valentina , Luetteke Noreen , Lopez Alex S. , Chen Liwei , Radisky Derek , Coppola Domenico , Wu Jie
Published: August 2012

SHP2 is a protein tyrosine phosphatase encoded by the PTPN11 gene. SHP2 is normally auto-inhibited by its regulatory N-SH2 domain. It is activated by several receptor tyrosine kinases and positively regulates the RAS/ERK and other signaling pathways by mechanisms that remain incompletely defined. Furthermore, gain-of-function activating SHP2 mutants have been found in human hematologic malignancies and solid tumors, including lung, colon, and prostate cancer. Previous studies have demonstrated the oncogenic activity of gain-of-function SHP2 mutants in the hematopoietic system. To investigate the biological functions of mutant SHP2 in vivo, we generated transgenic mice harboring a tetO-SHP2E76K transgene for tetracycline-inducible expression of the constitutively active SHP2E76K mutant. This allows us to examine the roles of the cancer-associated, Glu-76 mutant SHP2 in various tissues in bitransgenic mice. tetO-SHP2E76K mice were crossed with CCSP-rtTA or SPC-rtTA mice for inducible expression of SHP2E76K in the lung type II pneumocytes. Elevated levels of active Erk1/2 and Src were detected in the lungs of bitransgenic mice induced with doxycycline. Focal hyperplasia of bronchioloalveolar epithelial cells was observed within one month of doxycycline induction in bitransgenic mice, which progressed to more extensive atypical adenomous hyperplasia and adenoma after six months. These results suggest that Shp2 is a proto-oncogene of lung carcinoma.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4005. doi:1538-7445.AM2012-4005
Abstract 4030: Wnt antagonist SFRP4 acts as a tumor suppressor gene in gastric carcinomas
Authors: Kim Jin , Lee Hee Eun , Jee Chang Do , Kim Woo Ho
Published: August 2012

Secreted frizzled-related proteins (SFRPs) function as Wnt signaling antagonists and have important implications in carcinogenesis. SFRP4, a member of the SFRP family, have been found to be down-regulated by promoter hypermethylation in various cancers. However, functional significance of SFRP4 has not been investigated in gastric carcinoma. In this study, we examined aberrant DNA methylation and expression of SFRP4 in gastric cancer cell lines, and we found that SFRP4 was hypermethylated and down-regulated in 9 out of 10 (90%) gastric cancer cell lines. Bisulfite DNA sequencing confirmed the densely methylated SFRP4 promoter region and addition of the demethylating agent 5-aza-2α-deoxycytidine and/or histone deacetylase inhibitor trichostatin A restored the mRNA expression of SFRP4. Methylation-specific PCR (MSP) analysis showed that SFRP4 gene promoter is frequently methylated in gastric cancer tissues (75%) but not in adjacent normal gastric tissues. We then investigated whether methylation of SFRP4 is associated with age, sex, tumor stage, histology, and overall survival. No significant association was found between the methylation status of SFRP4 and these clinicopathological variables. However, promoter methylation of SFRP4 was found to be significantly correlated with poor survival in gastric carcinomas (p = 0.045). Restoration of SFRP4 function in non-expressing gastric cancer cells induced tumor suppressor-like features such as induces gastric cancer cell apoptosis, inhibits cell proliferation, colony formation, migration, and invasion. Conversely, knocking down SFRP4 by small interfering RNA in gastric cancer cell lines promotes cell proliferation and inhibits apoptosis. In addition, over-expression of SFRP4 repressed Wnt target genes and induced changes in the expression of numerous genes related to cell cycle, proliferation, invasion, metastasis, and apoptosis in gastric cancer cells. Our results suggest that promoter hypermethylation is one of the important mechanisms of SFRP4 gene silencing in gastric carcinogenesis and that SFRP4 methylation in gastric carcinoma is associated with a poor outcome in such patients.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4030. doi:1538-7445.AM2012-4030
Abstract 4097: Integrative analysis of epigenetic and transcriptional alterations in head and neck squamous cell carcinomas
Authors: Gaykalova Daria A. , Vatapalli Rajita , Wei Yingying , Hennessey Patrick , Khan Zubair , Westra William , Khan Tanbir , Zaboli David , Sidransky David , Ochs Michael , Califano Joseph A.
Published: August 2012

Objective: Head and Neck Squamous Cell Carcinoma (HNSCC) is the sixth most common cancer worldwide with a 50% patient survival rate 5 years post-diagnosis despite current therapeutic strategies. A direct comprehensive genome wide integrated analysis of epigenetic and transcriptional alteration in primary HNSCC has not been performed before. Such data would greatly enrich our knowledge about HNSCC biology and would be beneficial for the development of the individual targeted therapy. Experimental Design: 44 primary HNSCC and 25 normal mucosal samples were used in the Affymetrix GeneChip Human Exon 1.0 array and for the Illumina Infinium Human Methylation 27 array. To analyze the data we employed a novel screening approach based on Cancer Outlier Profile Analysis (COPA). With use of this approach we determined 81 significant differentially expressed and 37 significant differentially methylated genes with both oncogenic and tumor suppressing properties. Results: Out of total 118 candidate genes we picked 36 candidate tumor suppressing genes with strong correlation between hypermethylation and decrease of expression in tumor samples, such as BANK1, ADFP, MAPK4, ZNF71 and others. 20 genes out of total 36 were validated by bisulfite sequencing in a separate cohort of 32 primary HNSCC tumor and 16 normal mucosal tissues. Out of the total 20 genes, 13 demonstrated at least 40% difference in methylation, most notably for BANK1 81% of tumors were more methylated as compared to normals. 7 of these newly discovered genes out of the 36 belong to Zinc Finger Proteins (ZNF) group and they have never been reported as tumor suppressors in HNSCC before. Bisulfite sequencing and quantitative real time PCR (qRT-PCR) analysis of ZNFs revealed that they are strongly hypermethylated and underexpressed in HNSCC tumor samples. Conclusions: Our new screening approach allowed identification of 36 candidate tumor suppressor genes aberrantly methylated and transcriptionally suppressed in HNSCC. Validation of gene expression and methylation allowed the detection of ZNF genes whose downregulation may play a significant role in HNSCC tumor development.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4097. doi:1538-7445.AM2012-4097
Abstract 416: Radiation-induced reprograming of breast cancer cells
Authors: Lagadec Chann H. , Vlashi Erina , Dekmezian Carmen , Pajonk Frank
Published: August 2012

Breast cancers are thought to be organized hierarchically with a small number of breast cancer stem cells (BCSCs) able to re-grow a tumor while their progeny lack this ability. Recently, several groups reported enrichment for BCSCs when breast cancers were subjected to classical anticancer treatment. However, the underlying mechanisms leading to this enrichment are incompletely understood. Using non-BCSCs sorted from patient samples, we found that ionizing radiation reprogrammed differentiated breast cancer cells into induced BCSCs (iBCSCs). iBCSCs showed increased mammosphere formation, increased tumorigenicity and expressed the same stemness-related genes as BCSCs from non-irradiated samples. Reprogramming occurred in a polyploid subpopulation of cells, coincided with re-expression of the transcription factors Oct4, Sox-2, Nanog, and Klf4, and could be partially prevented by Notch inhibition. We conclude that radiation may induce a BCSC phenotype in differentiated breast cancer cells and that this mechanism contributes to increased BCSC numbers seen after classical anti-cancer treatment.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 416. doi:1538-7445.AM2012-416
Abstract 4202: Genetic re-programming of the AML cell line HL-60 during differentiation: Roles of the EGR/NAB and NR4A transcription factors
Authors: Roberts Michael , Briceno Nicole , Bugel Jamie , Campbell Catherine , Dickinson Mary , McCarthy Trevor , Oldach Phoebe , Stanley Natalie , Forrester Jeffrey
Published: August 2012

HL-60 cells represent an established line of human acute myeloid leukemia cells that can be induced to differentiate along several distinct myeloid lineages. Phorbol esters activate a signaling network, which includes the protein kinase C (PKC) pathway, causing the leukemia cells to differentiate into macrophage-like cells. As the leukemia genetic program is converted to the macrophage program, the cells exit the cell cycle, undergo morphological changes, become adherent, display other macrophage properties, and ultimately initiate apoptosis. This study provides a detailed DNA microarray analysis with qRT-PCR validation of the genetic network of the leukemia cell during first 24 hours post-induction of differentiation. We present data describing the global changes in gene expression at the RNA-level at 0.5, 1, 3, 6, 12, and 24 hours post-PMA treatment and information about specific genes with regard to their RNA and protein expression levels. Approximately 2,000 genes were identified that exhibit significant changes in mRNA levels from the leukemia expression program. A cluster analysis was performed to group these genes by their pattern of expression resulting in a collection of distinct expression profiles and associated functional profiles. These genes encode transcription factors, intracellular signal transducers, receptors, cytokines and a variety of other proteins. Of particular interest in understanding the genetic re-programming of the leukemic cells is the transcription factor expression profile. In addition to the established roles of the NF-kappa-B and AP-1 transcription factors in HL-60 cell differentiation, we present possible roles for the EGR/NAB and NR4A transcription factor families in both differentiation and initiation of apoptosis. A variety of biological analysis strategies using the expression data to define regulatory groupings that characterize the changing genetic network in these cells, including interaction networks and pathway activations have been carried out. Taken together, we seek to better understand the genetic program defining leukemia cells and the mechanisms by which oncogenic mutations can be overridden to achieve cell cycle arrest, differentiation and apoptosis.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4202. doi:1538-7445.AM2012-4202