bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 4451: Targeted therapy of lung cancer using ScFvEGFR-Heparin-Cisplatin nanoparticles
Authors: Peng Xianghong , Wang Yiqing , Wang Yuxiang , Huang Donghai , Chen Zuo Georgia , Nie Shuming , Shin Dong M.
Published: June 2012

The clinical use of cis-diamminedichloridoplatinum(II) (cisplatin, CDDP) is restricted by severe side effects, including nephrotoxicity, peripheral neuropathy, and ototoxicity. Although the nanoparticles has been used for CDDP delivery in animal models and demonstrated to reduce the side effects and increase the antitumor effects of CDDP, most of studies used none-targeted nanoparticles for CDDP delivery via enhanced permeability and retention (EPR) effect. However, utilizing EPR effect for delivery of CDDP achieves only passive tumor targeting. We have developed novel nanoparticles by conjugating single-chain antibodies to epidermal growth factor receptor (ScFvEGFR) to modified heparin, and loaded CDDP into the targeted nanoparticles (EHDDP). Our results showed that the intracellular Pt was significantly higher in EHDDP treated cells (27.91± 2.45 ng Pt/105 cells) than that of free DDP (2.49± 0.39 ng Pt/105 cells) (P=0.004) and non-targeted nanopartcles HDDP(2.14± 0.20 ng Pt/105 cells) (P=0.003) at 4 hrs, while the internalization of Pt in free CDDP treated cells didn't show any significant difference as compared with that in HDDP (P=0.25). The Pt (166.05±21.17pg Pt/ug DNA) which was intercalated into DNA in EHDDP treated cells increased significantly as compared with that in CDDP(42.34±10.57pg Pt/ug DNA) (P=0.015) and HDDP(20.27±2.88 pg Pt/ug DNA) (P=0.008) treated cells. We found that the CDDP-loaded nanoparticles could significantly change the biodistribution of Pt in mice comparing with the free CDDP. Accumulation of Pt in subcutaneous tumor lesions in EHDDP group (13.45±2.15ng/mg dry tissue) was significant higher than that in HDDP (4.87±0.67ng/mg dry tissue) (P=0.026) and CDDP groups (1.48±0.52ng/mg dry tissue) (P=0.02) 24 hours after the intravenously injection (Pt, 2.5mg/kg) into nude mice bearing H292 tumors. The systemic delivery of EHDDP (2.5 mg/kg; 5 times treatment at 3 days intervals) to mice showed significant enhanced antitumor activity with no body weight loss or damages to kidney, liver, and spleen, while the mice that received free CDDP had significant weight loss and massive organ damages. Our results suggest that EHDDP nanoparticles have the potential to be used for targeted therapy of cancer which expresses EGFR with reduced side effects. (Supported by P50CA128613).

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4451. doi:10.1158/1538-7445.AM2011-4451
Abstract 4454: Cancer therapy using pulsed HIFU and a rose bengal derivative
Authors: Kim Yoo-Shin , Rubio Valentina , Xia Rongmin , Qi Jianjun , Shi Zheng-Zheng , Peterson Leif , Tung Ching-Hsuan , O'neill Brian E.
Published: June 2012

High intensity focused ultrasound (HIFU) has been combined with a Rose Bengal derivative (RB2) to provide a synergistic cytotoxicity requiring the presence of both ultrasonic cavitation and drug. Unlike most sono-sensitizers, RB2 is not a photo-sensitizer, meaning it has no side effects associated with ambient light. In vitro tests have shown that a short treatment (less than 30s) of pulsed HIFU at 1 MHz with power sufficient for cavitation destroys <90% of breast cancer cells in suspension with 15uM of the compound. Neither the pulsed HIFU nor the RB2 compound was found to have any significant impact on the viability of the cells when used alone. Introducing an antioxidant (N-acetylcysteine, NAC) reduced the effectiveness of the treatment, suggesting the possibility of an oxidative mechanism. In vivo tests using these same cells growing as a xenograft in mice were also done. Using similar treatment parameters in vivo necessitated the use of ultrasound contrast agents to initiate cavitation. When this was done, we were able to demonstrate rapid tumor regression for combination pulsed HIFU and RB2 treatments. RB2 was delivered in large doses of 25 mg/kg i.v. without any adverse side effects. In some animals, ablating a tumor with cavitation resulted the subsequent regression of both treated and control tumors. We believe it should be possible to develop this technology into an alternative safe and effective means of tumor ablation for breast cancer treatment.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4454. doi:10.1158/1538-7445.AM2011-4454
Abstract 4464: Ciclopirox Olamine alters PEAK-1-mediated cytoskeleton organization and invasion of metastatic cancer cells
Authors: Weems Jessica M. , Klemke Richard L.
Published: June 2012

The majority of cancer patients die from metastatic disease because there are no drugs available to prevent the spread of cancer and eradicate metastases in patients. The antimycotic drug ciclopirox olamine (CPX) is under investigation as a repositioned drug candidate which has anti-tumor and anti-angiogenesis activity in experimental models. Because CPX has been FDA tested and shows exceptionally low side effects in patients even at high doses, it has significant potential as both a therapeutic to prevent cancer recurrence after surgical resection and for the long term systemic treatment of cancer patients with overt metastatic disease. However, CPX has not yet been tested for its ability to inhibit metastatic cell function. In this study we examined the ability of CPX to inhibit metastatic cancer cell migration, invasion, and proliferation, and evaluated the signal transduction pathways that regulate these processes. Interestingly, CPX was observed to inhibit the expression of the tyrosine kinase, pseudopodium-enriched atypical kinase 1 (PEAK1), which is necessary for proper remodeling of the actin cytoskeleton and focal adhesion dynamics in metastatic cancer cells (PNAS, 107(24), 10920-5). Associated with the decrease in PEAK1 expression by CPX was decreased total cellular tyrosine phosphoprotein content, pseudopodium protrusion, cancer cell spreading, movement, and proliferation on extracellular matrix proteins. Collectively, our findings indicate that at therapeutic doses, CPX potently alters cytoskeletal signaling, cancer cell movement, and proliferation by modulating PEAK1 activity. These findings are important in light of the fact that PEAK1 amplification and cytoskeleton modulation have been linked to anchorage-independent cell growth, cell migration, and tumor progression in human gastrointestinal cancers. The exceptional safety record of CPX and our findings support the notion that CPX has significant potential as a repositioned therapeutic agent to combat cancer recurrence and spread in patients.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4464. doi:10.1158/1538-7445.AM2011-4464
Abstract 4467: Role of 12-lipoxygenase in regulation of ovarian cancer growth
Authors: Guo Austin M. , Al-Wahab Zaid , Liu Xiuli , Maddippadi Krishna Rao , Ali Rouba , Scicli A. Guillermo , Munkarah Adnan
Published: June 2012

Eicosanoid-related enzymes may be implicated in the pathogenesis of ovarian cancer. We found that high grade serous ovarian carcinoma had a significantly higher level of 12-LOX expression than normal ovarian epithelium. These data led us to hypothesize that the lipoxygenase pathway is important in the regulation of ovarian cancer growth. In the present study, we examined the role of 12-lipoxygenase (12-LOX), the main human 12-HETE generating enzyme, in the regulation of proliferation and survival in epithelial ovarian cancer in vitro and ovarian cancer development and angiogenesis in vivo. Down-regulation of the 12-LOX expression using 12-LOX siRNA also resulted in markedly reduction in the epithelial ovarian cancer (EOC) OVCAR-3 growth as we have previously observed with BMD-122, a selective 12-LOX inhibitor. In addition, BMD-122 significant inhibited the VEGF expression whereas purified 12-HETE increase VEGF expression in OVCAR-3 cells. Furthermore, we found that BMD-122 markedly decreases angiogenesis induced by OVCAR-3 in a Matrigel plug angiogenesis assay. Systemic administration of BMD-122 to nude mice bearing experimentally-induced ovarian cancer resulted in a 60 % decrease in tumor size. These data suggest that 12-LOX may be involved in regulation of ovarian cancer growth, survival and cancer-induced angiogenesis. Thus inhibition of 12-LOX could be useful as adjuvant therapy of ovarian cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4467. doi:10.1158/1538-7445.AM2011-4467
Abstract 4481: Topical application of the dual PDPK1/AKT inhibitor PHT-427 inhibits signaling and growth of human breast cancer cutaneous metastases in mice
Authors: Kirkpatrick D. Lynn , Johnson Jenny L.H. , Lemos Robert , Abdelemelek Mena , Ihle Nathan , Powis Garth
Published: June 2012

Despite advances in the treatment of breast cancer between 10 to 15% of patients develop cutaneous metastatic disease (CMD) most frequently on the face, neck and chest wall, usually in later stages of the disease as a harbinger of metastasis that will occur in other organs 1 to 3 years later. CMD is not life threatening but can significantly impact patients’ quality of life and is a cause of anxiety, pain, discomfort, and a portal for infection. CMD could also be a seed for metastases at other sites. Surgery or radiotherapy is used for single or localized CMD. Topical (epicutaneous) therapy with molecularly targeted agents provides an attractive modality for treatment of more widespread breast CMD. PHT-427 is a dual pleckstrin homology (PH) domain inhibitor of PDPK and AKT, two key enzymes of PI3K signaling that is frequently activated in breast cancer. We report here PHT-427's topical activity in CMD. MCF-7 human breast cancer (mutant PIK3CA) 106 cells in 20 μI were injected intradermaly in the flank of estradiol pelleted female nu/nu mice. When tumors reached 40-200 mm3 groups of 5 mice were treated twice a day with 0.1 ml vehicle or vehicle with 50 mg/ml PH-427, applied to a 1 cm patch of skin over the tumor. Mice were housed individually with collars to prevent them ingesting applied drug. After 10 days mice were euthanized 4 hr after the last application and blood, tumor and overlying skin were removed for analyses. Topical PHT-427 gave 89 % inhibition of tumor growth (p = 0.017, 3/5 no measurable tumor). There was no change in body weight and no apparent skin toxicity. Western blotting showed that PHT-427 inhibited p-AKT Thr308/Ser473 in skin and tumor, and decreased total AKT in skin but not tumor. p-PDPK1 Ser241 was inhibited in tumor but not skin, as was the downstream target pPKC Thr410 and pMAPK Thr202/Tyr204. Measurement of PHT-427 by HPL-MS showed very high levels in the skin at the site of application, levels of ∼50 μg/g in tumor and 5.5 μg/ml in plasma. In vitro levels of PHT-427 of 5 μg/ml are required for killing of sensitive cell lines. Thus, topical application of PHT-427 can deliver active drug levels to skin and tumor, inhibiting PDPK1 and AKT, and significantly inhibiting tumor growth without adverse effects on normal skin. Topical PHT-427 could have use in skin conditions driven by PDPK/AKT such as prevention of sun damage and skin cancer, and in the personalized therapy of breast CMD.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4481. doi:10.1158/1538-7445.AM2011-4481
Abstract 4485: Preclinical characterization of PWT33597, a dual inhibitor of PI3-kinase alpha and mTOR
Authors: Matthews David J. , O'Farrell Marie , James Joyce , Giddens Anna C. , Rewcastle Gordon W. , Denny William A.
Published: June 2012

Phosphoinositide-3-kinase (PI3K) is an important mediator of tumor cell growth, survival and proliferation. In particular, PI3K alpha is important for signaling downstream of receptor tyrosine kinases and is also frequently amplified or mutationally activated in tumors, suggesting that selective inhibitors of this isoform may have therapeutic utility in the treatment of cancer. Downstream of PI3K, the mTOR kinase also plays a critical role in cellular growth and metabolism, and inhibitors of mTOR have demonstrated clinical benefit in several tumor types. We report here the discovery and characterization of PWT33597, a dual inhibitor of PI3K alpha and mTOR. PWT33597 inhibits PI3K alpha and mTOR in biochemical assays with IC50 values of 19 and 14 nM respectively, and is approximately 10-fold selective with respect to PI3K gamma and PI3K delta. Profiling of PWT33597 against 442 protein kinases (Ambit Kinomescan) revealed little or no cross-reactivity with either serine/threonine or tyrosine kinases, and there was little cross-reactivity with an additional panel of 64 pharmacologically relevant targets. In NCI-H460 and HCT116 tumor cells with mutationally activated PI3K alpha, PWT33597 inhibits phosphorylation of PI3K and mTOR pathway proteins with cellular IC50 values similar to its biochemical IC50 values. PWT33597 has good pharmacokinetic properties in multiple preclinical species, is not extensively metabolized in vivo and shows little potential for interaction with cytochrome P450 enzymes. Following a single oral dose in vivo, PWT33597 shows durable inhibition of PI3K and mTOR pathway signaling in xenograft tumors. High compound distribution into tumors and potent anti-tumor activity has been observed in multiple tumor xenograft models with activated PI3K/mTOR pathways. Also, administration of PWT33597 in mice is associated with transient increases in plasma insulin, consistent with an effect on PI3K/AKT signaling. A robust PK/PD relationship has been defined, which will guide interpretation of the planned phase I clinical study. IND-enabling studies with PWT33597 are currently in progress.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4485. doi:10.1158/1538-7445.AM2011-4485
Abstract 4495: Treatment effects of the novel mTOR kinase inhibitor AZD8055 in prostate cancer cell models
Authors: Dai Yao , Siemann Dietmar
Published: June 2012

The mTOR pathway is frequently hyperactivated in prostate cancer due to PTEN loss of function, hence rendering prostate cancer cells sensitive to mTOR inhibitors. Although the classic allosteric mTOR inhibitor rapamycin has shown considerable preclinical efficacy, clinical results suggest that rapamycin alone is insufficient to inhibit tumor growth in prostate cancer patients. AZD8055 is an ATP-competitive mTOR kinase inhibitor that efficiently blocks activation of both mTOR complex (mTORC) 1 and 2. In this study we evaluated the effects of AZD8055 in prostate cancer cell models. Cell proliferation after drug treatment was determined by MTT assay and cell cycle was analyzed using propidium iodide staining followed by flow cytometry. Protein expression was detected by Western blot. In both PC-3 (PTEN null) and DU145 (PTEN wildtype) cells, AZD8055 suppressed cell proliferation at the nanomolar level in a dose dependent manner. At the same concentration (100 nM), AZD8055 induced greater G1 phase arrest than rapamycin and the expression of proteins related to G1 progression (cyclin D1, c-Myc) was significantly decreased by AZD8055 while only slightly reduced by rapamycin. Mechanistically, although both drugs blocked phosphorylation of mTORC1 downstream targets S6K and S6, only AZD8055 inhibited phosphorylation of 4E-BP1, another mTORC1 downstream molecule, and Akt, a typical target of mTORC2. Importantly, cells that were able to survive and proliferate under rapamycin (100 nM) selective pressure remained responsive to AZD8055, even at the lowest dose (10 nM). Furthermore in a PC-3 cell line established to be highly resistant to rapamycin (PC-3RR), AZD8055 could still potently decrease cell proliferation, with an IC50 of 0.5 nM. Taken together, these findings indicate that a) AZD8055 is superior to rapamycin in growth inhibition of prostate cancer cells irrespective of PTEN status, b) AZD8055 is able to deactivate rapamycin-insensitive complexes involved in the mTOR signaling, and c) AZD8055 treatment can overcome rapamycin treatment-associated resistance. In summary, the novel mTOR kinase inhibitor AZD8055 may have significant therapeutic potential in prostate cancer treatment.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4495. doi:10.1158/1538-7445.AM2011-4495
Abstract 4522: Identification of small molecule agonists/activators of BMP-2, 4, 7 signaling
Authors: Vrijens Karen , Lin Wenwei , Cui Jimmy , Shelat Anang , Taylor Michael , Guy Kip R. , Chen Taosheng , Roussel Martine F.
Published: June 2012

Medulloblastoma (MB) is the most common malignant pediatric brain tumor. MB is a cancer of the cerebellum that occurs in children between the ages of 3 and 7. Human MBs have been classified into four subgroups, two of which harbor mutations in pathways that regulate normal development of the brain: Sonic Hedgehog/Patched (Shh/Ptch) (25%) and Wnt (15%). Our laboratory found that the bone morphogenetic proteins (BMP-2, 4, 7) antagonize Shh signaling by inducing the irreversible differentiation of MB cells into neurons leaving normal post-mitotic neurons intact. We designed a cell-based luciferase assay in which a human carcinoma cell line, C33A, expressed a multimerized BMP-responsive element from the Id1 promoter linked to luciferase. We then screened 3,488 compounds with known bioactivity and 31,441 compounds from the St. Jude diversity library for small molecule agonists of the BMP-2, 4, 7 signaling cascade. To date, 14 candidate compounds induced luciferase activity in a dose-dependent manner. Secondary screens showed that these small molecules induce P-Smad1/5/8 and Id2 expression in a dose-dependent manner in C33A cells by western blotting analysis, and alkaline phosphatase (ALP) activity which is a quantitative measure for the differentiation of C2C12 mouse myoblasts into osteoblasts. One of the compounds ventralized zebrafish embryos. Ongoing efforts are focused on understanding the mechanism of activation of BMP-4 signaling by these small molecule agonists.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4522. doi:10.1158/1538-7445.AM2011-4522
Abstract 4527: Pharmacodynamic and pathway analysis of three presumed inhibitors of poly (ADP-ribose) polymerase: ABT-888, AZD2281, and BSI201
Authors: Ji Jiuping , Lee Maxwell P. , Kadota Mitsutaka , Zhang Yiping , Parchment Ralph E. , Tomaszewski Joseph E. , Doroshow James H.
Published: June 2012

Poly (ADP-ribose) (PAR) polymerases (PARP1 and PARP2) are activated in response to DNA single-strand breaks and are pivotal to the base excision repair pathway for homologous recombination-defective cells or for the chemotherapy-damaged genome. ABT-888, AZD2281, and BSI201 are three presumed PARP inhibitors currently being evaluated in phase 1-3 clinical trials; each has demonstrated therapeutic activity either as a single agent for patients with BRCA-deficient malignancies or in combination with DNA-damaging chemotherapeutic agents. To compare the pharmacodynamics of these agents, we employed the BRCA1-defective breast cancer cell line MX-1 as a model. By monitoring γH2AX foci formation with a validated slide-based immunofluorescence assay, we found that γH2AX foci increased in a dose- and time-dependent fashion during treatment with each of the three drugs. However, utilizing our validated quantitative chemiluminescence ELISA for PAR (Clin. Cancer Res. 14: 6877, 2008), we unexpectedly found that PARP1/2 inhibition was dose and time dependent only for tumor cells treated with ABT-888 or AZD2281, but not BSI201. This observation was confirmed using ex vivo treatment of PBMCs from human whole blood. To investigate the mechanism of action of these drugs further, we used next-generation sequencing to identify genes that were induced or suppressed by exposure to these drugs. We found that a 4-hour exposure of MX-1 cells to a clinically achievable concentration of either ABT-888 or BSI201 produced expression changes in dramatically different sets of genes. Gene ontology and pathway analyses indicated that BSI201 specifically suppressed genes in the telomere pathway, suggesting PARP5/6 as potential targets and a different mechanism of γH2AX foci formation, whereas ABT-888 induced genes in the chromosome organization network, consistent with PARP1/2 as primary targets. These experiments strongly suggest that the major therapeutic mechanism of action of BSI201, unlike ABT-888 and AZD2281, is not mediated by inhibition of PARP1 or PARP2. Funded, in part, by NCI Contract No. HHSN261200800001E.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4527. doi:10.1158/1538-7445.AM2011-4527
Abstract 4561: Preclinical characterization of MT112/BAY 2010112, a novel PSMA/CD3-bispecific BiTE antibody for the treatment of prostate cancer
Authors: Lutterbuese Ralf , Friedrich Matthias , Kischel Roman , Rau Doris , Hoffmann Patrick , Ebert Evelyn , Zopf Dieter , Finnern Ricarda , Mueller Peter , Baeuerle Patrick A. , Wolf Andreas , Rattel Benno , Raum Tobias , Kufer Peter
Published: June 2012

Prostate-specific membrane antigen (PSMA) has been frequently selected as target antigen for antibody-based therapy of prostate cancer. Here, we recombinantly constructed a PSMA/CD3-bispecific BiTE antibody, called MT112/BAY 2010112. The BiTE antibody was produced in Chinese hamster ovary cells as a secreted protein of 55 kDa, showing high serum and thermal stability. MT112/BAY 2010112, purified as homogenous monomeric protein, bound at low nanomolar concentrations to defined epitopes on PSMA and CD3 antigens of human and macaque origin, respectively. In cell culture studies bispecific binding of MT112/BAY 2010112 selectively redirected human T cells against several PSMA-positive human prostate cancer cell lines as well as PSMA cDNA-transfected cell lines and potently induced specific target cell lysis with EC50 values ranging from 1 to 50 pM using non-stimulated human peripheral blood mononuclear cells as effector cells. EC50 values correlated with the number of PSMA molecules on the cell surface ranging from 37,000-500,000 molecules per cell among the cell lines analyzed.

The anti-tumor activity of MT112/BAY 2010112 was assessed in several SCID mouse models bearing subcutaneous xenografts derived from the human prostate cancer cell lines LNCaP, PC3 and 22Rv1. The BiTE antibody completely inhibited growth of tumors at doses as low as 0.005 mg/kg administered daily intravenously when human T cells and tumor cells were co-inoculated. Transient regression of tumors were observed in a model where human T cells were adoptively transferred into the peritoneal space of mice with subcutaneously established tumors.

These data suggest that the PSMA/CD3-bispecific antibody MT112/BAY 2010112 has high therapeutic potential for treatment of prostate cancer. Its cross-reactivity with human and macaque PSMA and CD3 antigens will greatly facilitate assessment of pharmacology, pharmacokinetics and safety during further pre-clinical development.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4561. doi:10.1158/1538-7445.AM2011-4561
Abstract 4571: 515H7, a novel anti-CXCR4 antibody: In vitro efficacy on CXCR4-associated signaling pathways and in vivo anti-tumor activity
Authors: Corvaia Nathalie , Berger Sven , Wurch Thierry , Boute Nicolas , Broussas Matthieu , Beau-Larvor Charlotte , Akla Barbara , Robert Alain , Haeuw Jean-François , Goetsch Liliane , Bailly Christian , Klinguer-Hamour Christine
Published: June 2012

Chemokines are small, secreted peptides that control the migration of leukocytes along a chemical gradient of ligand, especially during immune and inflammatory reactions. They are divided into two major subfamilies, CC and CXC, based on the position of their NH2-terminal cysteine residues, and bind to G protein coupled receptors, whose two major sub families are designated CCR and CXCR. More than 50 human chemokines and 18 chemokine receptors have been discovered so far. Chemokine receptor CXCR4/[Stromal cell-derived factor (SDF)-1] axis plays a central role in various physiological and pathological processes, including cancer. CXCR4 is over-expressed in a large number of tumors: colon, breast, prostate, lung, ovary, pancreas. CXCR4/SDF-1 axis is directly implicated in migration, invasion leading to metastases, cell proliferation and angiogenesis. Moreover, CXCR4 overexpression correlated with poor prognosis in many types of cancer.

A novel monoclonal antibody (Mab 515H7) was raised against the human CXCR4. It displayed efficacious antagonist properties for all major pathways associated with SDF-1-induced CXCR4 signaling in vitro. It was able to efficiently bind CXCR4 on both transfected cells and human tumor cell lines. It was found to strongly inhibit SDF-1 binding, Gα protein activation and beta-arrestin2 recruitment. It also blocked second messenger release (calcium, cAMP) and constrained by itself the formation of CXCR4 homodimers. It also inhibits SDF-1-induced cell migration in vitro. 515H7 Mab antitumor activities were also investigated in vivo using several human tumor models.

We demonstrated that 515H7 Mab was able to significantly inhibit growth of xenograft tumors in mice. In addition to its effect on tumor growth, 515H7 Mab was also able to significantly improve mice survival in the lethal U937 model.

The herewith data demonstrate that Mab 515H7 behaves as a potent and efficacious antagonist of all major CXCR4-controlled signaling pathways and suggest that targeting CXCR4 is a promising way for the treatment of tumors.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4571. doi:10.1158/1538-7445.AM2011-4571
Abstract 4577: A tetravalent bispecific TandAb for treating Hodgkin's lymphoma
Authors: Little Melvyn
Published: June 2012

Affimed has developed a tetravalent bispecific antibody (TandAb) for treating Hodgkin's lymphoma. It has a molecular weight of 105kDa and targets CD30 on Reed-Sternberg/Hodgkin cells and the FcγIIIA receptor (CD16A) on NK cells and macrophages. The anti CD16A antibody moiety does not bind the B isoform, which is present in relatively large numbers on granulocytes. Furthermore, in contrast to other therapeutic antibodies such as Rituximab, it binds with equal affinity to the various alleles of the receptor and should thus work equally well for all patients.

The anti CD30 x anti CD16A TandAb has been granted Orphan Drug Status by both the FDA and EMEA. To provide toxicological and clinical material, a robust CMC production process was established with a good yield. The purified TandAb successfully completed an extensive toxicology programme in cynomolgus monkeys. No adverse clinical events occurred and no measurable amounts of antibodies to the drug product were found. The Tandab can probably be stored for a long time in its present lyophilised formulation, since no loss of activity has been observed on storage at 40degC for one year. A clinical Phase 1 trial started on October 5th. So far the treatment has been well tolerated with no adverse events.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4577. doi:10.1158/1538-7445.AM2011-4577
Abstract 4596: Phenethyl isothiocyanate inhibits growth of MIAPaca2 human pancreatic cancer xenograft in vivo in association with apoptosis induction
Authors: Stan Silvia D. , Singh Shivendra V. , Whitcomb David C. , Brand Randall E.
Published: June 2012

Pancreatic cancer is the fourth leading cause of cancer-related deaths in the U.S. with a 5-year survival rate of less than 5%. Low survival rate for patients with pancreatic cancer points towards an increased need for novel chemoprevention, early detection, and therapeutic strategies for this disease. This study was undertaken to determine the efficacy of phenethyl isothiocyanate (PEITC), a naturally occurring isothiocyanate found in cruciferous vegetables, against pancreatic cancer cells in vitro and in vivo. Exposure of human pancreatic cancer cells (MIAPaca2, PL-45, and BxPC3) to PEITC resulted in growth inhibition, which was accompanied by apoptotic cell death regardless of the K-ras status. Apoptotic cell death by PEITC treatment was characterized by an increase in cytoplasmic histone-associated DNA fragmentation and enrichment of sub-diploid fraction. PEITC-induced apoptosis correlated with induction of pro-apoptotic protein Bak, down-regulation of anti-apoptotic proteins Bcl-2 and Bcl-xL, and cleavage of caspase-3 and PARP. Oral administration of 12 µmol PEITC/mouse (five times per week) significantly retarded the growth of MIAPaca2 xenografts in male nude mice without causing weight loss or any other signs of toxicity. PEITC administration significantly reduced proliferation as determined by PCNA and Ki-67 stainings and increased apoptosis in tumors as shown by TUNEL assay. In conclusion, the present study demonstrates, for the first time, that PEITC administration retards the growth of human pancreatic cancer xenografts by inducing apoptotic cell death. The present study provides pre-clinical evidence for development of PEITC as a chemopreventive agent for pancreatic cancer. This investigation was supported in part by the Wayne Fusaro Pancreatic Cancer Research Fund (DCW), the Shirley Hobbs Martin Memorial Fund (REB), and the NCI grants CA101753 and CA113363 (SVS).

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4596. doi:10.1158/1538-7445.AM2011-4596
Abstract 4617: Bioactive phytochemicals in wheat bran for colon cancer prevention
Authors: Sang Shengmin , Zhu Yingdong
Published: June 2012

Colorectal cancer is a leading cause of cancer deaths in the United States. Many studies have found that dietary cereal fibers protect against colon cancer, however, not all cereal fibers are equally effective. Wheat bran is the only cereal bran that shows consistent protection against colon cancer in laboratory animal models, and corn and oat bran may enhance colon tumorigenesis. We and others have reported that phytochemicals in wheat bran instead of fiber are the major active components for colon cancer prevention. However, the active components are still unknown. Using human colon cancer cells (HCT-116 and HT-29) as the guiding assay, we further purified the active components from wheat bran using column chromatography. In this study, we identified fraction containing 5-n-alkylresorcinols (ARs) had the strongest inhibitory effect on the proliferation of human HCT-116 and HT-29 colon cancer cells. Further purification led to the identification of 5-n-heptadecylresorcinol (C17:0) and 5-n-nonadecylresorcinol (C19:0) as the major active components, whereas 5-n-heneicosenylresorcinol (C21:0) and 5-n-tricosylresorcinol (C23:0) had no inhibitory effects, indicating that the length of the side chain of ARs significantly affects their activities. The effects of other components in wheat bran, such as sphingolipids, will also be discussed. In summary, we identified all the major components in wheat bran and our study indicates that 5-n-alkylresorcinols are the major active colon cancer preventive agents in wheat bran and the length of the alkyl chain significantly affects 5-n-alkylresorcinols’ cancer preventive activities. 5-n-Alkylresorcinols are phenolic lipids present in high amounts in wheat bran and are not found in oat and corn bran. Our finding will help us to further understand why wheat bran inhibits and oat and corn bran (which do not contain ARs) have no effect or enhance colon carcinogenesis.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4617. doi:10.1158/1538-7445.AM2011-4617
Abstract 4709: miR-337-3p and its targets STAT3 and RAP1A modulate paclitaxel sensitivity in non-small cell lung cancers (NSCLCs)
Authors: Du Liqin , Subauste Maria C. , Baker Michael , DeSevo Christopher , Borkowski Robert , Zhong Shihua , Schageman Jeoffrey J. , Greer Rachel , Yang Chin-Rang , Girard Luc , Gazdar Adi F. , Wistuba Ignacio I. , Minna John D. , Pertsemlidis Alexander
Published: June 2012

We are addressing the questions of whether microRNAs (miRNAs) play a functional role in modulating drug sensitivity of lung cancer cells, and whether miRNA expression levels can be manipulated to increase drug sensitivity in lung cancer treatment. Using a combination of in silico and in vitro approaches, we identified miR-337-3p as a modulator of paclitaxel sensitivity in NSCLC cell lines where over-expression of miR-337-3p sensitizes NSCLC NCI-H1155 cells to paclitaxel (>2 fold) and docetaxel (>10 fold) by enhancing taxane-induced mitotic arrest. Of several possible targets of miR-337-3p we found that Stat3 and Rap1A are the direct targets responsible for mediating miR-337-3p sensitization to paclitaxel. In studies of multiple NSCLC lines we found that miR-337-3p can, in general, sensitize NSCLC lines to paclitaxel, and that Stat3 expression is significantly correlated with paclitaxel resistance in NSCLC lines, suggesting that tumor Stat3 expression is an intrinsic determinant and biomarker for paclitaxel response. We conclude we have discovered a novel pathway modulating NSCLC paclitaxel sensitivity, which involves the down-regulation of Stat3 and Rap1A expression by miR-337-3p. These findings have prompted: our ongoing studies of patient samples annotated for miR-337-3p, Stat3, and Rap1A expression and response to taxane therapy; preclinical testing of a miR-337-3p mimic as an adjuvant to taxanes for NSCLC therapy; and further tests of this pathway to provide both new therapeutic targets and biomarkers predictive of response for NSCLC taxane based therapy.

This research was supported by NIH R01 CA129632 from the National Cancer Institute and by P50 CA70907 from the UT Southwestern/MD Anderson Cancer Center Lung Specialized Program of Research Excellence.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4709. doi:10.1158/1538-7445.AM2011-4709
Abstract 4746: Type I NKT cells mediate anti-tumor immunity through a TNF-α- and NOS-dependent pathway when stimulated with β-ManCer
Authors: O'Konek Jessica J. , Illarinov Petr , Khursigara Deborah Stewart , Ambrosino Elena , Izhak Liat , Castillo Bernard F. , Raju Ravinder , Khalili Maryam , Kim Hee-Yong , Howell Amy , Besra Gurdyal S. , Porcelli Steven A. , Berzofsky Jay A. , Terabe Masaki
Published: June 2012

CD1d-restricted type I NKT cells have been shown to play a critical role in the induction of tumor immunity by producing IFN-γ, which activates effector arms such as NK cells and CD8+ T cells. It has been considered that IFN-γ is necessary for type I NKT cell-induced tumor immunity. In this study, we show that type I NKT cells can induce strong tumor immunity through an IFN-γ-independent pathway when activated with a new type of agonistic antigen, β-mannosylceramide (β-ManCer). The protection induced by β-ManCer treatment was completely abrogated in type I NKT cell deficient Jα18 KO mice. With the observations that in vitro activation of type I NKT cells by β-ManCer was blocked by anti-CD1d blocking monoclonal antibody and that β-ManCer-loaded CD1d dimers bind to type I NKT cells and stimulate type I NKT cell hybridomas in an APC-free system, we concluded that recognition of CD1d presented β-ManCer by a TCR of type I NKT cells is necessary for the protection. Surprisingly β-ManCer-induced protection was not abrogated in IFN-γ deficient mice, which is in contrast with the protection induced by a prototypic agonist α-galactosylceramide (α-GalCer). Instead, β-ManCer-induced protection was dependent on nitric oxide synthase (NOS) and TNF-α since blockade of either completely abrogated the protection while the blockade did not affect protection induced by α-GalCer. The conclusion that NKT cells activated with β-ManCer utilize a different pathway from that used by the cells activated with α-GalCer to enhance tumor immunity was confirmed with the observation that the combination of both antigens synergistically enhanced tumor immunity when suboptimal doses of each were used. These data demonstrate that NKT cells mediate tumor immunity through a TNF-α- and NOS-dependent pathway when stimulated with β-ManCer and that β-ManCer represents a new class of type I NKT cell agonist. Since we observed that human type I NKT cells also can be activated by β-ManCer, β-ManCer may provide a new intervention against cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4746. doi:10.1158/1538-7445.AM2011-4746
Abstract 4758: Inhibition of checkpoint kinase 1 (Chk1) as a potential therapeutic for pediatric neuroblastoma
Authors: Russell Mike R. , Cole Kristina A. , Maris John M.
Published: June 2012

Neuroblastoma is a cancer derived from cells of the sympathetic nervous system that manifests with significant clinical heterogeneity. Although children diagnosed with low-risk neuroblastoma are very likely to be cured, high-risk patients are frequently resistant to even the most intensive of multi-modal regimens, and at least half of these children suffer relapse that is almost always fatal. To address the unmet need for novel therapeutic targets, our lab conducted an unbiased siRNA screen and determined that the loss of cell cycle checkpoint kinase 1 (Chk1) produced the most robust cytotoxic effect across multiple neuroblastoma cell lines. We subsequently confirmed that many neuroblastoma cell lines express constitutively phosphorylated Chk1 – a discovery that is supported by identical findings in tumors obtained from high-risk patients. Here we present evidence that the combination of a small molecule inhibitor of Chk1 with either irinotecan (SN-38) or cisplatin was synergistic or additive in vitro in cell lines sensitive to single agent Chk1 inhibition. Inhibition of Chk1 signaling as potential therapy in neuroblastoma is further supported by complimentary experiments in which we found that induction of shRNA specific for Chk1 results in marked cytotoxicity. To further understand the chemosensitizing aspect of Chk1 inhibition in neuroblastoma cells, we assayed the ATR/Chk1 pathway for potential biomarkers predictive of response. Candidate signaling partners in this pathway were isolated based upon either pharmacological inhibition or shRNA-induced silencing of Chk1, followed by hybridization to antibody microarrays. This technique has allowed for identification of Chk1-related signaling proteins involved in the DNA damage response pathway. Lastly, we have assessed the efficacy of Chk1 inhibition in an in vivo xenograft mouse model of pediatric neuroblastoma. We found that daily administration of a small molecule Chk1 inhibitor, currently undergoing Phase I clinical testing, was able to significantly impede the growth of NB1643 neuroblastoma xenografts (p=0.001). Efforts are currently underway in our laboratory to investigate a potentially synergistic effect in vivo through co-administration of this inhibitor with irinotecan or cisplatin. Taken together, these results provide a strong rationale for further studies to assess the use of Chk1 inhibition as either a single-agent or combinatorial therapy in pediatric neuroblastoma.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4758. doi:10.1158/1538-7445.AM2011-4758
Abstract 4809: Epigenomic profiling of oral cancer
Authors: Yoshiba Sayaka
Published: June 2012

Despite combined surgery and radiation therapy, long-term survival for oral cancer has not improved over the past several decades. This is primary due to poor clinical prognosis of patients with the lymph nodes metastasis. Therefore, deeper understanding of the molecular basis of highly malignant property and patient stratification along with these characters are needed.

Although, recent genome-wide analyses of DNA methylation have revealed a large number of aberrantly methylated genes in many cancers, and allowed us to identify the molecularly defined subgroups such as CpG island methylation phenotype (CIMP) in certain tumors, the methylation diversity of clinical oral cancers are still unknown. The purpose of this study is to characterize DNA methylation profiles of oral cancer tissues (six normal oral mucosal swab, three non-cancerous mucosal tissues, and fifty-nine oral cancer tisseus) and to identify the specific methylation pattern related to the clinical features. Genome-wide methylation analysis was performed using Infinium HumanMethylation27 BeadArray system, which can analyze methylation status of 27,000 CpG sites semi-quantitatively, using 500ng of genomic DNA.We found 2,762 aberrantly methylated CpG sites in oral cancers against normal mucosa. By unsupervised clustering analysis, oral cancer could be divided into two methylation epigenotypes that are significantyly correlated with high incidence of lymph node metastasis and poor differentiation. We obtained the highly predictive candidates of classifier genes and they were confirmed by MassARRAY analysis. In summary, we identified two methylation epigenotypes related with clinical outcome in oral cancer, and candidate classifier genes would be useful clues of patient stratification for intensive therapy to overcome the tumor recurrence.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4809. doi:10.1158/1538-7445.AM2011-4809
Abstract 487: Evidence for tumor initiating stem cells in lung cancer
Authors: Zhang Wen Cai , Yang He , Soh Boon Seng , Sun Li Li , Chin Tan Min , Lim Elaine Hsuen , Lim Bing
Published: June 2012

Despite advances in our knowledge of the genetics of cancer and some progress in cancer treatment over the last few decades, lung cancer remains the leading cause of cancer mortality worldwide. Therefore the identification of new therapeutic targets is necessary and important.

By applying xeno-transplantation of primary cells from lung cancer specimens into immune deficient mice, we have identified a subpopulation of cells that can form tumor in transplanted mice which histologically resemble the primary tumor. This subpopulation can be enriched 200 fold for tumor initiating cells (TICs) by sorting primary tumor cells with a specific cell surface marker. The TIC population can give rise to unique epithelial colonies when seeded on feeders. Primary tumor cells when cultured serum free with EGF and FGF give rise to tumor-spheres that contain TICs at greater than 2% frequency. Microarray analysis of TICs from primary tumor samples, xenografts and tumor spheres are analyzed to derive “gene signature” of lung TICs. Several oncogenes and genes in metabolic pathways are overexpressed. Amongst them, LIN28B appears amongst the top list. Knockdown of LIN28B results in reduced tumor growth and, conversely, overexpression of LIN28B leads to transformation of NIH/3T3 and increases clonogenicity of normal lung fibroblasts.

The isolation of lung TICs should facilitate further investigation of the cellular origin and carcinogenesis of lung cancers.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 487. doi:10.1158/1538-7445.AM2011-487
Abstract 4904: Mechanisms of cytotoxicity of bifunctional epoxide cross-linking agents
Authors: Ng Christopher , Silvestri Vanesa L. , Lingar Morgan T. , Millard Julie T.
Published: June 2012

The discovery that bifunctional alkylating agents have antitumor activity led to the development of cancer chemotherapy over 50 years ago. While these compounds form a variety of cellular lesions, DNA interstrand cross-links are believed to be the most lethal, impeding both replication and expression of the genetic material. We are characterizing the mechanisms by which diepoxybutane (DEB) and the structurally related compound epichlorohydrin (ECH) exert their cytotoxic effects in cultured cells. Our first goal is to determine the relationship between interstrand cross-linking and cytotoxicity. We are assaying cross-linking ability in cultured cells using Hoechst 33258 to determine the amount of duplex DNA following alkaline denaturation. Only cross-linked DNA reanneals rapidly and interacts with the dye, which is highly fluorescent when bound to duplex DNA. Preliminary results in chicken 6C2 and human HL60 cells suggest a correlation between cross-linking and LD50 values for these compounds. Our second goal is to characterize the pathways by which these compounds induce apoptosis. Reverse-transcriptase real-time PCR analysis of HL-60 cells treated with DEB and ECH under conditions determined to induce apoptosis suggests up-regulation of several key genes involved in the mitochondrial apoptotic pathway, including BAK1, BAX, DIABLO, PUMA and APAF1. Finally, we are identifying the covalent structure of the ECH-cross-linked lesion via electrospray LC/MS. Characterization of the DNA modifications induced by these agents is an important step in understanding how these compounds exert their cytotoxic effects.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4904. doi:10.1158/1538-7445.AM2011-4904