bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 5055: Efficacy of cabazitaxel in mouse models of pediatric brain tumors.
Authors: Olson James M. , Girard Emily , Ditzler Sally , Richards Andrew , Lee Doonhoon , Vrignaud Patricia
Published: August 2014

Successful treatment of pediatric brain tumors is limited by significant long-term toxicities associated with surgery and radiation therapy on the developing central nervous system There is an unmet need for chemotherapy with improved efficacy in difficult to treat tumors, such as supratentorial primitive neuroectodermal tumors (sPNET) and atypical teratoid/rhabdoid tumors (ATRT), as well as diagnoses that currently have good long-term survival, such as medulloblastoma. Overcoming the blood brain barrier is a large hurdle in effectively treating brain tumors, particularly when there is a need, as with very young patients, to avoid radiation therapy. Cabazitaxel is a promising taxane derivative shown to effectively kill tumor cells in pre-clinical in vitro and in vivo experiments. Similar to docetaxel, cabazitaxel has favorable drug properties and a manageable safety profile in patients with advanced solid tumors, with the advantage of being able to cross the blood brain barrier. Additionally, cabazitaxel has shown efficacy in docetaxel resistant tumors. The experiments presented here, tested the relative efficacy of cabazitaxel and docetaxel in mouse models of pediatric brain tumors. A spontaneous mouse model of medulloblastoma driven by Smo activation was evaluated by magnetic resonance imaging for tumor growth and blood brain barrier integrity before and after treatment with cabazitaxel or docetaxel. Efficacy of cabazitaxel and docetaxel against patient-derived pediatric brain tumors was tested in flank and orthotopic xenograft models of medulloblastoma, sPNET, ATRT, and ependymoma. We observed regression in some flank xenograft tumors after treatment with cabazitaxel or docetaxel, with evidence of superior action of cabazitaxel. These data support further testing of cabazitaxel as a therapy to treat human pediatric brain tumors.

This work has been funded by Sanofi Inc.

Citation Format: James M. Olson, Emily Girard, Sally Ditzler, Andrew Richards, Doonhoon Lee, Patricia Vrignaud. Efficacy of cabazitaxel in mouse models of pediatric brain tumors. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5055. doi:10.1158/1538-7445.AM2013-5055
Abstract 5061: Roles for matrix metalloproteinase-3 (MMP-3) in the prostate tumor-bone microenvironment.
Authors: Frieling Jeremy S. , Atomi Pamen Lizzie , Cook Leah M. , Yang Shengyu , Lynch Conor C.
Published: August 2014

Prostate cancer commonly metastasizes to bone, resulting in lesions hallmarked by a mixture of osteolysis and osteogenesis. The “vicious cycle” is the paradigm describing tumor-bone interaction, and MMPs have been implicated in regulating the bioavailability and activity of growth factors that control the cycle. We have found that MMP-3, also known as stromelysin-1 and typically generated by host/stromal cells, is differentially expressed in the prostate tumor-bone microenvironment. Based on our initial observations, we hypothesize that host derived MMP-3 expression contributes to prostate tumor growth in bone.

Using an in vivo intratibial model of prostate to bone metastases (PaIII), we found that that tumor growth and tumor induced bone remodeling were significantly mitigated (p<0.05) in MMP-3 null animals compared to wild type controls. Using a candidate approach to examine potential mechanisms, we focused on parathyroid hormone related protein (PTHrP), a powerful regulator of osteoblast behavior in the vicious cycle. We identified that MMP-3 processes mature PTHrP1-36 to yield PTHrP1-16, PTHrP17-26, and PTHrP27-36 fragments in vitro. The fragments did not impact osteoblast proliferation (MTT assay) or differentiation (Alizarin red staining), however, we observed a significant increase in migration of osteoblasts and osteoblast precursors in response to 10nM PTHrP1-16. The stimulation of migration by PTHrP1-16 was significantly greater than that induced by mature PTHrP1-36. Further analysis via confocal microscopy revealed a reduction in actin stress fibers as well as variations in lamellipodia and vinculin organization of osteoblasts treated with PTHrP1-16. In addition, western blots show a reduction of myosin light chain phosphorylation suggesting that PTHrP1-16 may mediate osteoblast migration by modulating Rho-associated protein kinase (ROCK) activity.

Our data demonstrate that host MMP-3 contributes to prostate tumor growth and tumor induced changes in bone remodeling in vivo. Further, we have identified that mature PTHrP1-36 is subject to cleavage by MMP-3 resulting in PTHrP1-16, PTHrP17-26, and PTHrP27-36 fragments of which PTHrP1-16 significantly stimulates migration of osteoblasts and osteoblast precursors. Collectively, these data indicate that specific inhibition of MMP-3 and/or targeting MMP generated neo-epitopes would be efficacious for the treatment of prostate to bone metastases.

Citation Format: Jeremy S. Frieling, Lizzie Atomi Pamen, Leah M. Cook, Shengyu Yang, Conor C. Lynch. Roles for matrix metalloproteinase-3 (MMP-3) in the prostate tumor-bone microenvironment. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5061. doi:10.1158/1538-7445.AM2013-5061
Abstract 5063: Matrilysin cleavage of perlecan produces bioactive fragments acting as a molecular switch to alter prostate cancer cell behavior.
Authors: Grindel Brian J.
Published: August 2014

Perlecan/HSPG2[PLN], a large heparan sulfate (HS) proteoglycan, is expressed in the basement membrane (BM) underlying epithelial and endothelial cells. During prostate cancer (PCa) cell invasion, a variety of proteolytic enzymes are expressed that digest BM components including PLN. After proteolysis, fragments of PLN can be released into circulation. A sandwich ELISA with antibodies generated across PLN detected fragments of PLN from IG-repeat domain IV in PCa patient serum. An enzyme upregulated in invasive PCa cells, matrilysin/matrix metalloproteinase-7 (MMP-7), was examined as a candidate for PLN proteolysis both in silico and in vitro. Purified PLN showed high sensitivity to MMP-7 digestion even when fully decorated with HS or when embedded with other BM proteins. MMP-7 fragments of PLN were detected as limit peptides by western blot. While not predicted in silico, MMP-7 cleaved every subpart of recombinantly generated PLN domain IV. The resultant MMP-7 generated PLN Dm IV fragments were identified by mass spectrometry (LC-MS/MS and MALDI) and Edman degradation N-terminal sequencing. Other PCa relevant enzymes had limited ability to cleave PLN including prostate specific antigen, hepsin and fibroblast activation protein. To determine if PLN digestion affects metastatic PCa cells, C4-2B cells were seeded on plates coated with different forms of PLN. Cells on intact PLN formed large clusters of poorly adherent cells, while those on PLN digested with MMP-7 or heparitinase to remove the HS chains attached and spread within 30 minutes. Immunohistochemistry of PCa patient tissue indicates MMP-7 and PLN are in direct contact at interfaces in the stroma. We conclude that enzymatic processing of PLN in the BM and stroma as occurs in the tumor microenvironment can alter PCa cell behavior and favor cell dispersion and invasiveness.

Citation Format: Brian J. Grindel. Matrilysin cleavage of perlecan produces bioactive fragments acting as a molecular switch to alter prostate cancer cell behavior. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5063. doi:10.1158/1538-7445.AM2013-5063
Abstract 5071: KGP94, a small-molecule cathepsin L inhibitor with antitumor activity.
Authors: Wittenborn Thomas , Trawick Mary Lynn , Pinney Kevin G. , Chaplin David J. , Siemann Dietmar W. , Horsman Michael R.
Published: August 2014

Purpose: Cathepsins are a class of proteolytic enzymes recognized to play an important role in tumour progression, invasion and angiogenesis. The present study evaluated the anti-tumour activity of the small-molecule cathepsin L inhibitor KGP94 in a murine breast tumour model.

Materials and Methods: Male CDF1 mice were inoculated on the right rear foot with a C3H mammary carcinoma. A solution of KGP94 was prepared each day by dissolving in a mixture of 10% Tween 80 and 90% HEPES-buffer. It was intraperitoneally injected at 0.01ml/g mouse bodyweight. Various doses (5-20mg/kg) were administered between 5-20 days, starting either from the day of tumour implant or when tumours had reached a volume of 200mm3. Tumour response was assessed by determining the tumour growth time, which was either the time in days to reach a volume of 500mm3 (TGT500) for animals treated from the day of tumour implant, or 1000mm3 (TGT1000) for animals treated when tumours were at a volume of 200mm3. Results are listed as Mean (± Standard Error). One-way ANOVA with a posthoc Student-Newman-Keuls comparison of group means was performed, and a P<0.05 was considered significant.

Results: The TGT500 for control animals was 18.3 days (± 0.4). Treating tumours with 10mg/kg for 5 days significantly increased the TGT500 to 21.9 days (± 0.7). When the time of treatment with this dose was increased to 10 or 20 days, no additional growth inhibition was observed. Varying the drug dose for this 5 days treatment period showed that the TGT500 with 5mg/kg and 20mg/kg were 23.5 days (± 1.9) and 23.4 days (± 1.1), respectively. For experiments in which treatments were started when tumours had already reached 200mm3 an effect on TGT1000 was only observed with the highest drug dose at 20mg/kg; the respective TGT1000 being 5.9 days (± 0.2) for controls and 8.3 days (± 0.7) for KGP94.

Conclusion: This synthetic, small-molecule cathepsin L inhibitor significantly delayed tumour growth, but the effect was primarily on the early phase following tumour inoculation. Such an effect suggests that KGP94 may have a role to play in inhibiting metastatic development rather than influencing the growth of established tumours.

Supported by The Danish Cancer Society, The Danish Council for Independent Research: Medical Sciences, and OXiGENE Inc.

Citation Format: Thomas Wittenborn, Mary Lynn Trawick, Kevin G. Pinney, David J. Chaplin, Dietmar W. Siemann, Michael R. Horsman. KGP94, a small-molecule cathepsin L inhibitor with antitumor activity. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5071. doi:10.1158/1538-7445.AM2013-5071
Abstract 5075: Targeting TSP1 and inhibiting angiogenesis in UV-induced skin cancer by apigenin.
Authors: Tong Xin , Bridgeman Bryan B. , Mirzoeva Salida , Crawford Susan E. , Volpert Olga V. , Pelling Jill C.
Published: August 2014

Non-melanoma skin cancer (NMSC) is a major health problem in the United States, with over two million new cases diagnosed yearly. Among many genetic and environmental factors contributed to NMSC, ultraviolet B (UVB) radiation is the major carcinogen. As with all solid tumors, angiogenesis is a necessary prerequisite for the progression and metastasis of NMSC. Thrombospondin-1 (TSP1) is the first endogenous inhibitor of angiogenesis to be identified, and its expression is markedly downregulated in epidermis following UVB irradiation and throughout distinct steps of skin carcinogenesis. Apigenin (4’, 5, 7-trihydroxyflavone), a nonmutagenic plant flavonoid, inhibits UV-induced NMSC in mice. However, the molecular mechanisms of apigenin's chemopreventive function remain elusive. For the first time, we found that apigenin restores normal TSP1 levels in UVB-irradiated skin keratinocytes in vitro and in vivo. The regulation of TSP1 expression in UVB/apigenin-treated keratinocytes occurs post-transcriptionally and is mediated by RNA-binding protein Human antigen R (HuR). Importantly, HuR has recently been demonstrated to play an important role in translation of TSP1 mRNA, and we showed that apigenin promotes cytoplasmic localization of HuR, where polyribosomal translation of TSP1 occurs. In addition, knockdown of HuR by siRNA abrogates the ability of apigenin to maintain normal TSP1 levels in UVB-irradiated keratinocytes. Furthermore, apigenin inhibits microvascular density (MVD) in superficial dermis that occurs in response to UVB irradiation. Taken together, our results demonstrate that apigenin promotes TSP1 expression in UVB-irradiated epidermis via HuR leading to inhibition of angiogenesis. Identifying TSP1 as a key target of apigenin and demonstrating its important role in chemoprevention by apigenin will provide a compelling rationale to use apigenin for maintaining the expression of protective TSP1 in the skin as a novel strategy for NMSC prevention and treatment.

Citation Format: Xin Tong, Bryan B. Bridgeman, Salida Mirzoeva, Susan E. Crawford, Olga V. Volpert, Jill C. Pelling. Targeting TSP1 and inhibiting angiogenesis in UV-induced skin cancer by apigenin. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5075. doi:10.1158/1538-7445.AM2013-5075
Abstract 5077: Anti-angiogenesis and anti-cancer activities of ZK002, a C-type lectin-like protein isolated from snake venom.
Authors: Yu Shan , Dai Xiangrong , Tai William C.S. , Choi Roy C.Y. , Liang Chaofan , Li Benjamin X.y. , Tsim Karl W.K. , Hsiao Wendy W.L.
Published: August 2014

Snake venoms contain various biologically active proteins including C-type lectins and -like proteins (CTLs), phospholipases, proteinases and metalloproteinases, that could target diverse cellular processes. Among these active components, CTLs have demonstrated antithrombotic effects through their platelet agglutination and coagulation activities. In our study, we have detected anti-angiogenesis activity from the venom of Deinagkistrodon acutus snake. The partial purified fraction of snake venom with anti-angiogenesis activity was isolated through a stepwise separation in anion-exchange and cation-exchange chromatography. At the same time, the monoclonal antibody was generated and used for further protein purification by affinity chromatography. This highly purified protein was named as ZK002. By MALDI-TOF mass spectrometry determination, the mass of ZK002 is about 30KD. By LC-MS/MS analysis, protein sequence of highly purified ZK002 was determined and compared with the Deinagkistrodon acutus snake protein database. ZK002 is a heterodimer of CTLs consisting of alpha and beta peptide chains. Using In vitro chicken embryo chorioallantoic membrane assay and human umbilical vein endothelial cell (HUVEC) tube formation assay, it showed that ZK002 exhibited an anti-angiogenesis effect. Moreover, ZK002 also demonstrated an anti-cancer effect as shown in the ApcMin/+ mouse model for colorectal cancer. Administration of ZK002 significantly suppressed the total number and the size of tumors and showed no observable adverse effect. To further elucidate the anti-angiogenesis functions of ZK002, we deduced the coding DNA sequences from the peptide sequences of the alpha- and beta-chains, then subcloned individual gene sequence into yeast and mammalian expression vectors. Results showed that the recombinant vectors express secreted peptides with the expected molecular weight. Transient transfection of the alpha- and beta-recombinant vectors individually or in combination inhibit tube formation in HUVEC cells, suggesting that both alpha- and beta-chains possess anti-angiogenesis activity. The success of cloning and expression of recombinant ZK002 would greatly facilitate the future development of ZK002 as anti-angiogenesis and anti-cancer drugs.

(This work is supported by the Innovation and Technology Fund (UIM208) of Hong Kong Government)

Citation Format: Shan Yu, Xiangrong Dai, William C.S. Tai, Roy C.Y. Choi, Chaofan Liang, Benjamin X.y. Li, Karl W.K. Tsim, Wendy W.L. Hsiao. Anti-angiogenesis and anti-cancer activities of ZK002, a C-type lectin-like protein isolated from snake venom. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5077. doi:10.1158/1538-7445.AM2013-5077
Abstract 5079: Endoglin requirement for BMP9 signaling in endothelial cells reveals new mechanism of action for selective anti-Endoglin antibodies.
Authors: Nolan-Stevaux Olivier P. , Zhong Wendy , Wickramasinghe Dineli , Ruefli-Brasse Astrid
Published: August 2014

Endoglin (ENG), a co-receptor for several TGFβ-family cytokines, is expressed in activated endothelial cells alongside ALK1, the ACVRL1 gene product. ENG and ACVRL1 are both required for angiogenesis and mutations in either gene are associated with Hereditary Hemorrhagic Telangectasia, a rare genetic vascular disorder. ENG and ALK1 function in the same genetic pathway but the relative contribution of TGFβ and BMP9 to SMAD1/5/8 activation and the requirement of ENG as a co-mediator of SMAD phosphorylation in endothelial cells remain debated. Here, we show that BMP9 and TGFβ1 induce distinct SMAD phosphorylation responses in primary human endothelial cells and that, unlike BMP9, TGFβ1 only induces SMAD1/5/8 phosphorylation in a subset of immortalized mouse endothelial cell lines, but not in primary human endothelial cells. We also demonstrate, using siRNA depletion of ENG and novel neutralizing anti-ENG antibodies, that ENG is required for BMP9/pSMAD1 signaling in all human and mouse endothelial cells tested. Finally, anti-ENG antibodies that interfere with BMP9/pSMAD1 signaling, but not with TGFβ1/pSMAD3 signaling, including the TRC105 clinical candidate, also decrease in vitro HUVEC endothelial tube formation and inhibit BMP9 binding to recombinant ENG in vitro. Our data demonstrate that BMP9 signaling inhibition is a key and previously unreported mechanism of action of TRC105, an anti-angiogenic anti-ENG antibody currently evaluated in clinical trials.

Citation Format: Olivier P. Nolan-Stevaux, Wendy Zhong, Dineli Wickramasinghe, Astrid Ruefli-Brasse. Endoglin requirement for BMP9 signaling in endothelial cells reveals new mechanism of action for selective anti-Endoglin antibodies. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5079. doi:10.1158/1538-7445.AM2013-5079
Abstract 5084: Overcoming the resistance to anti-angiogenic therapy: Itraconazole blocks blood vessel maturation and synergizes with anti-VEGF therapy.
Authors: Fu Chenglai , Gerber Stephanie , Castillo Richmond , van der Zwan Anita , Kachhap Sushant , Hammers Hans
Published: August 2014

Background: Anti-angiogenic drugs, such as sunitinib, have been used as a first line therapy for renal cell carcinoma and some other cancers. However, the development of resistance to angiogenesis inhibitors targeting the VEGF pathway is common and impedes the efficacy of cancer treatments. Previously, we found it that blood vessel maturation is a common feature of tumors resistant to sunitinib. Thus, we hypothesized that novel approaches of inhibiting pericyte coverage of the tumor vasculature could be a successful approach to sensitize resistant tumors to sunitinib. Approach: An in vitro angiogenesis model was developed for screening the pericyte recruitment inhibitors. Itraconazole, an anti-fungal drug, was found to block the association of pericyte with newly-formed blood vessel endothelial cells. A sunitinib resistance animal model of Myc-Cap prostate cancer xenograft was used for studying the in vivo effect of treatment. Animals were dosed with itraconazole, sunitinib or the combination when tumors were well established. Result: through the in vitro angiogenesis model, the association of pericyte with endothelial cells was significantly reduced by itraconazole treatment. Its mechanism of action involved inhibition of focal adhesion kinase activity, a protein that plays a central role in cell spreading, differentiation, migration and cell death. Moreover, itraconazole treatment showed reduced pericyte coverage of tumor vasculature in vivo, and synergized with sunitinib treatments. Conclusion: These findings indicated that itraconazole is effective in inhibiting the pericyte coverage of the tumor vasculature and broaden the efficacy of sunitinib. Our results support further preclinical and clinical evaluation of itraconazole combination therapies in cancer treatment.

Citation Format: Chenglai Fu, Stephanie Gerber, Richmond Castillo, Anita van der Zwan, Sushant Kachhap, Hans Hammers. Overcoming the resistance to anti-angiogenic therapy: Itraconazole blocks blood vessel maturation and synergizes with anti-VEGF therapy. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5084. doi:10.1158/1538-7445.AM2013-5084
Abstract 5085: Less tumor engraftment after anti-VEGF therapy in pediatric low grade astrocytoma.
Authors: Sie Mariska , Sikkema Arend H. , Scherpen Frank J.G. , ter Elst Arja , Kampen Kim R. , Hoving Eelco W. , den Dunnen Wilfred F.a. , de Bont Eveline S.j.m.
Published: August 2014

Introduction. Low grade astrocytomas are the most frequent brain tumors in children. Although children can benefit from treatments including neurosurgery, chemotherapy and radiotherapy, still children die due to tumor progression. Furthermore, morbidity can be serious. So new therapeutic strategies are warranted for these patients. Previously, we showed that angiogenesis is a characteristic of pediatric low grade astrocytoma (Sie et al, NAN 2010). Therefore, vascular endothelial growth factor (VEGF), the most critical angiogenic factor, may be a potential therapeutic target. The present study aimed to analyze the effect of VEGF inhibition in vitro and in vivo in pediatric low grade astrocytoma.

Materials and methods. Three different pediatric low grade astrocytoma cell lines were used: Res-186 (WHO grade I astrocytoma), Res-259 and UW-467 (WHO grade II astrocytoma). Effects in vitro of the anti-VEGF monoclonal antibodies, bevacizumab (0 - 50 ug/ml, Avastin®, anti human VEGF) and B20-4.1.1 (0 - 200 ug/ml, anti human and mouse VEGF) were studied using a WST-1 cell viability assay and a cell proliferation assay with BRDU. Res-259 cells were orthotopically implanted in NOD-scid IL2Rgnull mice. After 6 weeks of treatment intraperitoneal twice weekly with bevacizumab (15 mg/kg), B20-4.1.1 (5 mg/kg) or phosphate buffered saline as control group, mice were euthanized and tumor engraftment was studied in brain slides using Aperio's imagescope viewer.

Results. In vitro cell growth was not changed as measured by WST-1 and BRDU incorporation. In vivo results showed less tumor engraftment in bevacizumab (n = 10) and B20-4.1.1 (n = 9) treated mice compared with the control group (n = 10) (resp. 70%, 44%, 100%). In the bevacizumab and B20-4.1.1 treated mice tumor mass was lower as compared with controls (resp. P = 0.062, P = 0.001).

Conclusion(s). This study showed less tumor engraftment after anti-VEGF therapy in a newly developed pediatric low grade astrocytoma mouse model. In these tumors anti-VEGF seems to work especially on tumor microenvironment. Suggesting that anti-VEGF could have a potential role in the therapeutic strategy for children with low grade astrocytoma, thoughtfulness on possible tumor escape mechanisms that may arise will be crucial.

[W.F.A. den Dunnen and E.S.J.M. de Bont shared senior authorship.]

Citation Format: Mariska Sie, Arend H. Sikkema, Frank J.G. Scherpen, Arja ter Elst, Kim R. Kampen, Eelco W. Hoving, Wilfred F.a. den Dunnen, Eveline S.j.m. de Bont. Less tumor engraftment after anti-VEGF therapy in pediatric low grade astrocytoma. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5085. doi:10.1158/1538-7445.AM2013-5085
Abstract 5086: The side effects of sorafenib in treating hepatocellular carcinoma.
Authors: Sun Hui-Chuan , Zhang Wei , Zhu Xiao-Dong , Lu Lu , Zhang Qiang-Bo , Tang Zhao-You
Published: August 2014

Sorafenib, a tyrosine kinase inhibitor of VEGFR and B-Raf, is a standard treatment for advanced hepatocellular carcinoma (HCC). However, there are several clinical observations showing discontinuous sorafenib treatment associated with more metastasis or rapid relapse. We tested effect of sorafenib on tumor growth and metastasis in different dosing and schedules in liver cancer allograft or xenograft models. The results showed a lower dose sorafenib treatment will induce more intrahepatic or lung metastasis while the primary tumor growth is still inhibited in HCC with a higher expression of HTATIP2 but not in HCC with a lower expression of HTATIP2. Further studies showed sorafenib decreased HTATIP2 expression only in HCC with a higher expression of HTATIP2. The clinical data also supported the patients with lower HTATIP2 expression in tumor benefit from sorafenib treatment while patients with a higher HTATIP2 expression in tumor did not. We also observed the effect of sorafenib on host (mouse) immunity after we found pre-treatment by sorafenib before implantation of tumor resulted in more lung metastasis. We found interleukin 12 (IL12) was significantly inhibited by sorafenib, which is responsible for more lung metastasis. In conclusion, our study showed the side effect of sorafenib may promote tumor progression if sorafenib treatment is stopped or not given in a full dose. These findings may help to improve the efficacy of sorafenib by overcoming its side effects.

Citation Format: Hui-Chuan Sun, Wei Zhang, Xiao-Dong Zhu, Lu Lu, Qiang-Bo Zhang, Zhao-You Tang. The side effects of sorafenib in treating hepatocellular carcinoma. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5086. doi:10.1158/1538-7445.AM2013-5086

Note: This abstract was not presented at the AACR Annual Meeting 2013 because the presenter was unable to attend.
Abstract 5098: A mouse DLL4 cross-reactive variant of MEDI0639 disrupts functional vessel formation and inhibits tumor growth in preclinical models.
Authors: Cho Song H. , Jenkins David W. , Strout Patrick , Korade Martin , Zhong Haihong , Leow Ching Ching , Breen Shannon , Chesebrough Jon , Holoweckyj Nicholas , Inigo Ivan , Gololobov Gennady , Tsui Ping , Cook Kimberly , Damschroder Melissa , Czapiga Meggan , Brohawn Philip , Huang Jiaqi , Ricketts Sally-Ann , Maynard Juliana , Kamal Adeela
Published: August 2014

Delta-like ligand 4 (DLL4) is a membrane bound ligand for Notch receptors essential for functional vessel formation during development and angiogenesis. We have shown previously that MEDI0639, a human anti-DLL4 antibody, has potent in vitro and in vivo activity in blocking DLL4-Notch interaction. However, because MEDI0639 has low binding affinity to mouse DLL4, to enable in vivo pharmacology studies using xenograft tumor models in mice, MEDI0639 was engineered to bind more strongly to mouse DLL4. The resulting affinity-optimized variant antibody (anti-mDLL4 mAb) bound with high affinity to both human and mouse DLL4 and maintained binding specificity to DLL4. In a number of human cancer xenograft models in nude mice, the MEDI0639 variant antibody markedly inhibited the growth of tumors. qRT-PCR analysis using the Fluidigm platform showed decreases in mouse genes downstream of the Notch signaling pathway at efficacious doses, indicating on-target antibody effect on tumor vasculature. In addition, IHC and imaging analysis of xenograft tumors from the anti-DLL4 mAb dosed animals showed a dose-dependent increase in microvessel density and decrease in tumor perfusion compared to the control groups. In summary, we describe here the generation of mouse and human DLL4 cross-reactive antibody and the utilization of this antibody in demonstrating a positive correlation between the anticipated mechanism of action of DLL4 blockade on vasculature and inhibition of tumor growth.

Citation Format: Song H. Cho, David W. Jenkins, Patrick Strout, Martin Korade, Haihong Zhong, Ching Ching Leow, Shannon Breen, Jon Chesebrough, Nicholas Holoweckyj, Ivan Inigo, Gennady Gololobov, Ping Tsui, Kimberly Cook, Melissa Damschroder, Meggan Czapiga, Philip Brohawn, Jiaqi Huang, Sally-Ann Ricketts, Juliana Maynard, Adeela Kamal. A mouse DLL4 cross-reactive variant of MEDI0639 disrupts functional vessel formation and inhibits tumor growth in preclinical models. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5098. doi:10.1158/1538-7445.AM2013-5098
Abstract 5106: Circulating MACC1 transcripts are elevated in pancreatic cancer patient blood and correlate to locally advanced disease.
Authors: Stein Ulrike S. , Herrmann Pia , Fischer Christian , Schlag Peter M. , Detjen Katharina
Published: August 2014

Pancreatic cancer is a highly aggressive malignancy with a 5-year survival of < 5%. Late diagnosis, lack of prognostic markers and poor response to radiation and chemotherapies all contribute to the dismal prognosis. Surgery represents the sole curative treatment option. However, success is limited by invasive growth and metastatic spread, which frequently precede the onset of clinical symptoms and hence diagnosis.

Recently, we identified the novel gene metastasis-associated in colon cancer-1 (MACC1). MACC1 is a prognostic indicator for metastasis formation linked to metastasis-free survival of colorectal cancer patients. Circulating MACC1 transcripts in colorectal cancer patient plasma predict metastasis and survival. Correlations of MACC1 expression levels with tumor progression, recurrence and metastasis have meanwhile been reported for several cancers, e.g. gastric, lung and hepatocellular cancer. Here, we addressed the role of MACC1 in pancreatic cancer.

Immunohistochemical analysis of MACC1 in cryosections of human pancreatic cancer revealed strong reactivity of tumour duct epithelial cells, but not in the desmoplastic stroma. In contrast, weak immunoreactivity was present in non transformed pancreatic tissues, suggesting an induction of MACC1 in pancreatic malignancy. We furthermore analyzed blood levels of circulating MACC1 transcripts in pancreatic cancer patients. Circulating MACC1 transcript levels were elevated in pancreatic cancer patients, when compared to healthy volunteers. MACC1 transcript levels furthermore correlated to peripancreatic infiltration, but not to tumour size, tumor grading or angioinvasion.

Thus, MACC1 expression is induced in pancreatic cancer, which is reflected by increased circulating transcript levels in blood as well as high protein levels in the primary tumors. The correlation of MACC1 transcript levels with peripancreatic infiltration suggests a distinct function of MACC1 in pancreatic cancer cell biology, which translates into distinct clinical features of disease progression. Circulating MACC1 might therefore help to personalize treatment decisions in situations such as (neo-)adjuvant chemotherapy.

Citation Format: Ulrike S. Stein, Pia Herrmann, Christian Fischer, Peter M. Schlag, Katharina Detjen. Circulating MACC1 transcripts are elevated in pancreatic cancer patient blood and correlate to locally advanced disease. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5106. doi:10.1158/1538-7445.AM2013-5106
Abstract 5107: Phenotypic characterization of circulating tumor cells (CTCs) in triple negative breast cancer patients.
Authors: Kallergi Galatea , Markomanolaki Haris , Mavroudis Dimitrios , Georgoulias Vassilis , Agelaki Sofia
Published: August 2014

Triple negative (ER-negative, PR-negative, HER2-negative) considered as poor prognosis breast cancer patients without many therapeutic options. Circulating Tumor Cells (CTCs) have been proposed as a “real time liquid biopsy” in breast cancer patients. CTCs are associated with disease relapse and could serve as a target for molecular cancer therapies. The aim of the present study was the phenotypic characterization of CTCs in triple negative patients to explore new therapeutic strategies for these patients. We evaluated peripheral blood mononuclear cells (PBMC) cytospins from 29 triple negative patients, before the initiation of adjuvant (19 early) and front-line (10 metastatic) treatment. The expression of Cytokeratins (CK) (marker for CTCs), Estrogen Receptor (ER), Progesterone Receptor (PR), EGFR and HER2 in CTCs was assessed using double immunofluorescent experiments. Our results revealed that median expression per patient for ER, PR, EGFR and HER2 was 16.7%, 0%, 42.9% and 91.4%. The respective numbers for early versus (vs) metastatic patients were 29.7% vs 0% for ER, 27.1% vs 0% for PR, 70.8% vs 52.3% for EGFR and 50% vs 48.7% for HER2. In addition ER, PR, EGFR and HER2 were expressed in 33.1%, 28%, 67.7% and 45.1%, respectively, of the total examined CTCs. Triple staining experiments with the Ariol system could not revealed any no co-expression of CK/EGFR/ER in CTCs; however, there was only one patient with CTCs co-expressing CK/HER2/ER.

Consequently in order to identify whether chemotherapy could induce phenotypic changes of CTCs, 18 patients were analyzed after the completion of adjuvant treatment. ER, PR, EGFR and HER2 median expression per patients was identified in 0.2%, 15.2%, 66.7%, and 50% suggesting that adjuvant chemotherapy does not significantly influence the phenotype of CTCs in triple negative patients.The majority of CTCs in triple negative patients revealed expression of HER2 and EGFR implying that these receptors could be a potential target for the limitation of metastasis in these patients.

Citation Format: Galatea Kallergi, Haris Markomanolaki, Dimitrios Mavroudis, Vassilis Georgoulias, Sofia Agelaki. Phenotypic characterization of circulating tumor cells (CTCs) in triple negative breast cancer patients. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5107. doi:10.1158/1538-7445.AM2013-5107
Abstract 5110: Activation of Wnt/β-catenin, hedgehog and androgen receptor signaling pathways in solid pseudopapillary neoplasm of pancreas.
Authors: Park Minhee , Kim Minhyung , Hwang Daehee , Kim SangKyum , Park Eunsung , Paik Youngki , Park Jeonhan , Kim Hogeun
Published: August 2014

Solid pseudopapillary neoplasm (SPN), is an uncommon pancreatic tumor with distinct clinicopathologic features. Mutations in the exon 3 of β-catenin are characteristically identified in SPNs, however little is known about gene and microRNA expression characteristics. To investigate the molecular characteristics of SPNs, we analyzed mRNA and microRNA expression profiles of 14 SPNs and compared their expressions to that of 6 pancreatic ductal adenocarcinomas, 6 endocrine tumors of pancreas, and 5 non-neoplastic pancreas tissues. We demonstrated both mRNA and microRNA expression profiles completely distinguish SPNs to the other pancreatic tumors and non-neoplastic pancreas tissues. We found that Wnt/β-catenin, Hedgehog and androgen receptor signaling pathways are activated in SPNs by analyzing 1,686 genes that showed specific expression changes in SPN. We also found that 7 microRNAs were specifically down-regulated in SPNs, and miR-30a was most closely associated with the up-regulation of the genes belong to the three distinct activated pathways of SPN. We also demonstrated that genes involved in epithelial to mesenchymal transition (EMT) are up-regulated in SPNs than the other type of pancreatic tumors. SPN is characterized by increased expression of mesenchymal markers (N-cadherin, MMP9, Vercican, TIMP1) and decreased expression of epithelial markers (E-cadherin, Desmoplakin, Mucin1, Caveolin).

Considering that activated Wnt/β-catenin and Hedgehog pathways are related to the activation of the genes involved in EMT, these activated signaling pathways of SPNs can explain lack of epithelial cell differentiation, and the molecular mechanism of SPN tumorigenesis.

Citation Format: Minhee Park, Minhyung Kim, Daehee Hwang, SangKyum Kim, Eunsung Park, Youngki Paik, Jeonhan Park, Hogeun Kim. Activation of Wnt/β-catenin, hedgehog and androgen receptor signaling pathways in solid pseudopapillary neoplasm of pancreas. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5110. doi:10.1158/1538-7445.AM2013-5110
Abstract 5115: Inhibition of STAT-3 by piperlongumine induces anoikis in melanoma cells in vitro and blocks tumor formation potential in vivo.
Authors: Fofaria Neel M. , Srivastava Sanjay K.
Published: August 2014

The National Cancer Institute estimates that about 76,250 new cases of melanomas will be diagnosed in 2012 in the United States leading to at least 9810 related deaths. Metastasis of melanoma is the major challenge leading to the failure of its therapy. Hence, novel strategies to prevent metastasis are of prime importance. Anoikis is an anchorage independent cell death. Resistance to anoikis is one of the key features of a metastatic cell. In the current study, we show induction of anoikis by piperlongumine, a component of black pepper, by inhibition of STAT-3. Treatment of various melanoma cell lines in low attachment conditions with piperlongumine reduced the anoikis resistance in a concentration dependent manner. This decrease in anoikis resistance was associated with decrease in expression of STAT-3 and its phosphorylation at Y705. Significant down-regulation of Bcl-2 and Mcl-1, which are under the transcriptional regulation of STAT-3, was also observed by piperlongumine treatment indicating the role of STAT-3 in anoikis. Concentration dependent cleavage of poly (ADP-ribose) polymerase (PARP) was observed by piperlongumine treatment in melanoma cells. AG 490, an inhibitor of STAT-3 phosphorylation, alone induced anoikis in melanoma cells further indicating the role of STAT-3. IL-6 treatment not only increased the phophorylation of STAT-3 at Y05 but also abrogated the anoikis induced by piperlongumine. Silencing STAT-3 by shSTAT-3 sensitized the cells to piperlongumine treatment. On the other hand, over-expression of STAT-3 in SK-MEL28 and SK-MEL-2 cells conferred resistance to anoikis induced by piperlongumine. STAT-3 -/- SK-MEL-28 cells were highly sensitive to anoikis upon piperlongumine treatment. Finally, our in vivo studies established that melanoma cells treated with piperlongumine in suspension condition lost their potential to form tumors in mice. Taken together, our study suggests that the decrease in anoikis resistance induced by piperlongumine was mediated by STAT-3 inhibition. Notably, STAT-3 has been shown to be constitutively upregulated in melanoma rendering it resistant to chemotherapy and potential to metastasize. [Supported in part by R01 grant CA129038 (to S.K.S) awarded by the National Cancer Institute].

Citation Format: Neel M. Fofaria, Sanjay K. Srivastava. Inhibition of STAT-3 by piperlongumine induces anoikis in melanoma cells in vitro and blocks tumor formation potential in vivo. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5115. doi:10.1158/1538-7445.AM2013-5115
Abstract 512: p16INK4A down-regulation activates breast stromal adipocytes.
Authors: Alkhalaf Huda H. , Aboussekhra Abdelilah
Published: August 2014

Obesity, a disease linked to increased number of adipocytes in various tissues, is now recognized as a risk factor for the development of breast cancer. Importantly, obesity has been reported to be associated with the occurrence of larger, more advanced tumors and aggressive cancer pathological features, including lymph node metastasis, advanced tumor stage, and high grade. Cancer-associated adipocytes (CAAs), the most abundant cellular component of breast cancer-associated stroma, promote carcinogenesis through paracrine effects. However, the molecular basis of adipocytes implication in breast carcinogenesis remains elusive. To shed light on this important phenomenon, we established and characterized normal adipocytes from post-plastic surgery of breast tissues. We have shown that these cells express various adipocyte biomarkers, including Leptin, TNF-α and FABP4. Furthermore, we investigated the role of the tumor suppressor p16 INK4A protein in adipocytes activation. We have found that specific down-regulation of p16INK4A by shRNA increased the expression/secretion levels of various adipokines including leptin, activated breast adipocyte and enhanced their migration/invasion abilities. Consequently, media conditioned with these cells stimulated the proliferation and the migration/invasion of breast cancer cells and enhanced endothelial cell differentiation into capillary-like structures. In addition, we have also shown that media conditioned with breast cancer cells decrease the expression of p16INK4A and increase the expression of leptin in adipocytes.

These results provide the first indication that p16INK4A down-regulation in breast stromal adipocytes is an important step toward their activation.

Citation Format: Huda H. Alkhalaf, Abdelilah Aboussekhra. p16INK4A down-regulation activates breast stromal adipocytes. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 512. doi:10.1158/1538-7445.AM2013-512
Abstract 5123: In vitro culture for characterization of circulating GFP-expressing tumor cells in orthotopic lung cancer models .
Authors: Kološtová Katarína , Liberko Marián , Hroncová Eva , Hoffman Robert M. , Bobek Vladimír
Published: August 2014

In the present study circulating tumor cells (CTCs) were isolated from H460-RFP orthotopic human lung cancer model in mice. In vitro culture of CTCs has enabled us comparison of the chemosensitivity of tumor cells from primary H460 culture and of CTCs solated from blood grown in vitro. Cell line H460-RFP human lung cancer cells were grown to 70-80% confluence. Primary tumor were grown after subcutaneous injection of cultured cells. Fragments of tumor tissue (1 mm × 1 mm) were implanted into the lungs of nude mice. At 14 days, the mice were sacrificied and blood was taken by cardiac puncture for CTC-analysis. The blood (0.5 ml), obtained by cardiac puncture, was put into an EDTA tube (BD) and the CTC cells were enriched by immunomagnetic separation targeted to eptihelial antigens. The enriched fraction or whole blood was put into culture. Cell growth was then monitored by fluorescence microscopy. The isolation and culture of the fluorescent CTC will enable their further characterization.

Citation Format: Katarína Kološtová, Marián Liberko, Eva Hroncová, Robert M. Hoffman, Vladimír Bobek. In vitro culture for characterization of circulating GFP-expressing tumor cells in orthotopic lung cancer models . [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5123. doi:10.1158/1538-7445.AM2013-5123
Abstract 5129: AGR2 is a potential marker for metastatic human oral squamous cell carcinoma.
Authors: Chen Yi-Ting , Ho Chung-Liang , Chen Po-Ku , Chen Yuh-Ling , Chang Chung-Fa
Published: August 2014

Purpose: The mortality of oral cancer, which is a common subtype of human and neck squamous cell carcinomas (HNSCC), is increasing in Taiwan, Southeast Asia, and eastern countries during the last twenty years. Averagely, the 5-year survival rate of distant metastasis of oral carcinoma is less than 30-40%. Prevention of cancer metastasis to distant organs is one of practical approaches that may reduce the mortality of patients. This study aims to identify novel metastatic tumor markers for oral cancer.

Experimental Design and Results: A high metastatic sub-population, HSC-3-5 cells, was divided from human oral cancer HSC-3 by Transwell invasion assay. Our results indicated that HSC-3-5 cells exhibited higher metastatic capacities due to re-arrangement cytoskeleton and subsequently epithelial mesenchymal transition transformation in vitro. In addition, metastatic and tumorigenetic capacities of HSC-3-5 cells were characterized by spontaneous and experimental metastasis experiments in vivo. The microarray-based gene expression profiles of HSC-3/HSC-3-5 cells and their corresponded xenografts (orthotropic and heterotopic) were then performed. Anterior gradient 2 (AGR2), a pro-oncogenic signaling intermediate in various human cancers, was the most significantly up-regulated gene in HSC-3-5 cells compared with HSC-3. Furthermore, overexpression of AGR2 protein was verified in cells, xenograft animal models, and clinical patient tissues, and it encompassed positive relation with OSCC metastasis.

Conclusions: A high metastatic sub-population HSC-3-5 cell line derived from human oral cancer HSC-3 cells was divided. HSC-3-5 cells represented higher capacities not only in metastasis but also in tumorigenesis. According to microarray gene profiles and immunohistochemistry analysis, the expression of identified potential biomarker, AGR2, showed positive relationship with tumor metastasis during oral carcinogenesis.

Citation Format: Yi-Ting Chen, Chung-Liang Ho, Po-Ku Chen, Yuh-Ling Chen, Chung-Fa Chang. AGR2 is a potential marker for metastatic human oral squamous cell carcinoma. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5129. doi:10.1158/1538-7445.AM2013-5129