bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 4771: Regulatory role of an orphan nuclear receptor LRH-1 in castration-resistant growth of prostate cancer cells.
Authors: Xiao Lijia , Yu Shan , Hsiao Wendy W.L. , Chan Franky Leung
Published: August 2014

The advanced development of castration-resistant prostate cancer (CRPC) in patients upon androgen-deprivation therapy is generally believed to be mostly mediated by reactivation of androgen receptor (AR) signaling or its bypass with mechanisms involved, including clonal selection of androgen-independent or stem cell-like cell populations, AR hypersensitivity due to AR overexpression, and ligand promiscuity or independence by AR mutations, intratumoral conversion of adrenal androgens to high affinity AR ligands. Besides, the de novo steroid synthesis from cholesterol in CRPC has also been proposed. In this study, we found that the nuclear receptor liver receptor homolog-1 (LRH-1) might contribute to the CRPC growth or de novo steroid synthesis in prostate cancer cells through its positive regulation on expression of several critical enzymes in steroidogenesis, including CYP17A1, HSD3B1, HSD3B2 and StAR. Functional analyses showed that overexpression of LRH-1 could induce higher resistance to antiandrogen bicalutamide and steroid-depleted culture condition in AR-positive androgen-sensitive (LNCaP) but not in AR-negative androgen-insensitive (DU145) prostate cancer cells. In vivo tumorigenicity study showed that LNCaP-LRH-1 cells grew more aggressively in castrated or intact SCID mice, contrary to LNCaP-vector control cells that did not grow in castrated mice. Importantly, liquid chromatography-tandem mass spectrometry showed that intratumoral androgen concentrations (testosterone and DHT) were significantly higher in tumors formed by LNCaP-LRH-1 cells than those by LNCaP-vector control cells. Treatment of LNCaP-LRH-1 cells with a CYP17A1 inhibitor abiraterone could restore their sensitivity to bicalutamide and steroid-depleted culture condition. Gene knockdown of endogenous LRH-1 in AR-positive VCaP prostate cancer cells could not only suppress the mRNA expression of steroidogenic enzymes but also enhance their sensitivity to antiandrogen. Together, our results indicated that LRH-1 might play a regulatory role in advanced castration-resistant growth of prostate cancer via positive control on de novo steroid synthesis in prostate cancer cells.

(This work was supported by a Direct Grant for Research 2011/2012 and a RGC-GRF grant 2009/2010)

Citation Format: Lijia Xiao, Shan Yu, Wendy W.L. Hsiao, Franky Leung Chan. Regulatory role of an orphan nuclear receptor LRH-1 in castration-resistant growth of prostate cancer cells. [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 4771. doi:10.1158/1538-7445.AM2013-4771
Abstract 4915: Estrogen receptor β is expressed within breast cancer cells with stem cell like capacity and confers endocrine sensitivity.
Authors: Ma Ran , Govindasamy Karthik Muralidharan , Rosin Gustaf , Gustafsson John , Katchy Anne , Lindström Linda , Hilliges Camilla , Viberg Lisa , Blomqvist Lennart , Frisell Jan , Williams Cecilia , Fredriksson Irma , Bergh Jonas , Hartman Johan
Published: August 2014

Breast cancer stem-cells (BCSCs) are tumor-initiating cells expressing classical embryonal genes such as NANOG, SOX2 and NOTCH1, with a capacity to differentiate and form the heterogenous tumor mass in breast cancer. BCSCs are defined by their potential to grow as mammospheres in vitro together with their distinct cell-surface antigenic profile CD44+/CD24-/EpCAMlow as well as ALDH1-expression. It has been suggested that BCSCs are responsible for therapeutical resistance and metastasis.

About 70-80% of diagnosed breast cancers express ERα, which is demonstrated to have a central role in breast cancer progression and considered as a marker for endocrine sensitivity. However, in our research, BCSCs are confirmed to be ERα negative and supposed to be responding to estrogens only through paracrine signaling via stromal cells. We show that BCSCs purified from fresh surgically resected breast cancers express the second estrogen receptor; ERβ. It is also present in normal mammary stem cells (MSCs) isolated from breast reduction specimens. Surprisingly, stimulation of ERβ with a specific agonist expands the population of BCSCs but not MSCs . Knockdown of ERβ causes reduction in the number of mammospheres significantly along with decreased ALDH1 expression. We also find that treatment with tamoxifen is not sufficient to inhibit BCSCs proliferation although a specific ERβ antagonist reduces tumor growth in xenograft experiments as well as inhibits proliferation of primary cancer stem cells. In conclusion, we suggest endogenous ERβ is proliferative in cancer stem cells in vivo and in vitro, thus can be targeted by specific ligands, in turn opening up for a new direction in endocrine stem-cell specific therapy for breast cancer.

Citation Format: Ran Ma, Karthik Muralidharan Govindasamy, Gustaf Rosin, John Gustafsson, Anne Katchy, Linda Lindström, Camilla Hilliges, Lisa Viberg, Lennart Blomqvist, Jan Frisell, Cecilia Williams, Irma Fredriksson, Jonas Bergh, Johan Hartman. Estrogen receptor β is expressed within breast cancer cells with stem cell like capacity and confers endocrine sensitivity. [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 4915. doi:10.1158/1538-7445.AM2013-4915
Abstract 4935: PDZ–domain binding kinase promotes invasion in prostate cancer cells through up–regulation of matrix metalloproteinases–2 and –9.
Authors: Brown-Clay Joshua D. , Shenoy Deepika N. , Banerjee Partha P.
Published: August 2014

Members of the protein kinase superfamily of enzymes modulate many of the facets of the tumor phenotype, such as survival, proliferation, invasion and metastasis. Genetic, epigenetic or regulatory alterations can result in aberrant kinase behavior; the targeted inhibition of which has been a growing focus in anti-cancer drug development. PDZ-domain binding kinase (PBK) is an under-studied, dual-specificity serine/threonine kinase that has been shown to play a key role in cell division and regulation of multiple signaling pathways. It is expressed physiologically in spermatogenic germ and proliferating neural precursor cells, as well as aberrantly in a variety of cancer types. However, the role of PBK in prostate cancer has not been clearly defined. We have found that PBK expression varies greatly across a panel of human prostate cancer cell lines. Interestingly, the level of expression of PBK in prostate cancer cells directly correlates with their invasive ability. Since matrix metalloproteinases (MMP) -2 and -9 are key invasive effectors in a variety of cancers, we investigated their protein levels in relation to that of PBK. Expression of exogenous PBK in low PBK-expressing prostate cancer cell lines (LNCaP and VCaP) significantly upregulated levels of both the propeptide and active forms of MMP-2 and MMP-9; conversely, knockdown of PBK expression in a high PBK-expressing prostate cancer cell line (PC3M) significantly down-regulated both forms of these two MMPs. To determine if a change in PBK levels produces a significant phenotypic effect, we measured the effect of PBK overexpression or knockdown on the prostate cancer cell lines’ invasive ability, as measured in a modified Boyden chamber invasion assay. Overexpression of PBK increased prostate cancer cell invasion approximately ten fold, while PBK knockdown reduced PC3M invasive ability more than three fold. Moreover, immunohistochemical analysis revealed that PBK is present in the majority of human prostate cancer samples tested but not at all in the benign or normal human prostate tissue. These data indicate a novel function of PBK where its presence plays a role in invasion of human prostate cancer cells through up-regulation of MMP-2 and MMP-9. Therefore, the role of PBK in promoting cell invasion, combined with its general lack of expression in normal cells, nominates PBK as a potentially important therapeutic target for prostate cancer.

Citation Format: Joshua D. Brown-Clay, Deepika N. Shenoy, Partha P. Banerjee. PDZ–domain binding kinase promotes invasion in prostate cancer cells through up–regulation of matrix metalloproteinases–2 and –9. [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 4935. doi:10.1158/1538-7445.AM2013-4935
Abstract 4943: Peroxisome Proliferator-Activated Receptor γ inhibits cell nvasion, migration and epithelial-mesenchymal transition through up-regulating Galectin-9 in gastric cancer cells and in zebrafish xenograft model.
Authors: Cho Soo-Jeong , Kook Myeong-Cherl , Choi Il Ju
Published: August 2014

Background: PPARγ (peroxisome proliferator-activated receptor γ) is a member of the nuclear hormone receptor that is known to be anti-neoplastic. Little is known about clinical significance in gastric cancer (GC). We aimed to evaluate the mechanism related to tumor invasion, migration and epithelial-mesenchymal transition (EMT) in GC cells and in an animal model.

Methods: We controlled the expression of PPARγ and galectin-9 using siRNAs and lenti-viral constructs in human GC cells, and determined the effects of PPARγ and galectin-9 on EMT using RT-PCR, and on cell migration using transfilter assay and zebrafish xenograft model. Direct binding and interaction between PPARγ and galectin-9 were evaluated using luciferase and ChiP assays.

Results: Over-expression of PPARγ was accompanied by increased galectin-9 mRNA. Enhanced expression of PPARγ either galectin-9 increased the expression of E-cadherin, decreased the expression of N-cadherin, fibronectin, snail, MMPs-1, and -9, and reduced cell invasion and migration. Silencing either PPARγ or galectin-9 decreased the expression of E-cadherin, increased the expression of N-cadherin, fibronectin, and snail, and also increased cell migration and invasion. ChiP assay showed PPARγ bound to the promoter region of galectin-9. Luciferase assay demonstrated that the galectin-9 promoter activity significantly increased in PPARγ over-expressing cells compared to empty vector-treated cells, but significantly decreased in PPARγ siRNA-treated cells compared to scRNA-treated cells. PPARγ agonist caused dose-dependent cell death in GC cells, and increased the subdiploid fraction of DNA. In the zebrafish xenograft model, the number of zebrafishes in which transplanted AGS cells were migrated to tail vein and the number of migrated cancer cells were much less in PPARγ-overexpressing GC cells than in empty vector transfected cells, respectively.

Conclusions: PPARγ inhibits cell invasion, migration, and EMT through up-regulation of galectin-9 in vitro and in vivo. PPARγ could be a potential therapeutic target of GC.

Citation Format: Soo-Jeong Cho, Myeong-Cherl Kook, Il Ju Choi. Peroxisome Proliferator-Activated Receptor γ inhibits cell nvasion, migration and epithelial-mesenchymal transition through up-regulating Galectin-9 in gastric cancer cells and in zebrafish xenograft model. [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 4943. doi:10.1158/1538-7445.AM2013-4943
Abstract 497: Engagement of activatory Fc γ receptors by immunoregulatory receptor-targeting antibodies mediates antitumor activity.
Authors: Bulliard Yannick , Jolicoeur Rose , Windman Maurice , Rue Sarah , Knee Deborah , Wilson Nick , Dranoff Glenn , Brogdon Jennifer
Published: August 2014

Inhibitory FcγRIIB receptors are required for the therapeutic effects of agonistic antibodies targeting several tumor necrosis factor receptor (TNFR) superfamily members, including CD40, DR5, and Fas. However, it remains unclear how general this requirement is and whether activating FcγRs may be required for antibodies targeting other immunoregulatory receptors. Here we have explored the involvement of FcγRs for the antitumor effects of antibodies targeted to costimulatory TNFRs expressed on T cells. Surprisingly, FcγRIIB was completely dispensable for antibody-mediated anti-tumor effects. In contrast, activating FcγRs were required for maximal in vivo activity. A similar dependence on activating FcγRs was observed for antibodies targeted to the T cell surface antigen CTLA-4. Important changes in the tumor microenvironment and draining lymph nodes correlated with the in vivo efficacy of these antibodies. Our findings uncover a previously unknown requirement for activating FcγRs in the anti-tumor effects of immunomodulatory antibodies and raise important questions about the role of receptor signaling for therapeutic activity. A greater understanding of this activatory FcγR-based mechanism may improve the design and activity of immune-modulatory antibodies in clinical development, and those already approved for the clinic.

Citation Format: Yannick Bulliard, Rose Jolicoeur, Maurice Windman, Sarah Rue, Deborah Knee, Nick Wilson, Glenn Dranoff, Jennifer Brogdon. Engagement of activatory Fc γ receptors by immunoregulatory receptor-targeting antibodies mediates 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 497. doi:10.1158/1538-7445.AM2013-497
Abstract 4982: Comparison of T cell responses to a melanoma-related antigen in elderly and young melanoma patients.
Authors: Chakraborty Nitya G. , Singh Prashant , Dadras Soheil S. , Mukherji Bijay , Hegde Upendra P.
Published: August 2014

It is widely believed that a hypo-and/or dysfunctional state in T cells in the elderly is a negative factor in immune defense against cancer. Accordingly, cancer patients are often excluded from immune-based clinical trials and therapies. The incidence of melanoma is rapidly rising in the elderly. To our knowledge, a critical assessment of the immune responsiveness by the elderly against a relevant melanoma associated antigen has not been carried out. Using the MART-127-35 (M27) epitope as a melanoma-associated target epitope and M27 specific T cell receptor (TCR)-engineered T cells from the elderly (over 70) and young (below 45) as common elements in the comparison, we examined the T cell responses in both cohorts to the M27 epitope and to the Influenza matrix peptide MP58-66 (Flu58) as a control, ex vivo. We also compared the expressions of a number of genes associated with immune response by real-time reverse transcription polymerase chain reaction (qPCR) in formalin fixed primary melanomas from both cohorts, in situ.

While we detected a compromised CD8+ T cell response to Flu58 in the elderly, T cells from both cohorts proliferated and synthesized Th1 type cytokines in comparable levels when stimulated by the M27 epitope. qPCR analyses of primary melanomas from elderly patients showed lower levels of Fox-P3 expression but revealed comparable levels of expression of IL-2, IFNγ, TNF α, IL-4, IL-10, IDO, and TGFβ. These findings indicate that elderly patients are quite capable of responding to tumor antigens and need not be excluded from immune-based therapies or clinical trials.

Citation Format: Nitya G. Chakraborty, Prashant Singh, Soheil S. Dadras, Bijay Mukherji, Upendra P. Hegde. Comparison of T cell responses to a melanoma-related antigen in elderly and young melanoma 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 4982. doi:10.1158/1538-7445.AM2013-4982
Abstract 4992: A novel role of soluble E-selectin as a chemoatractant to human leukocytes through the PI3kinase signaling pathway in breast cancer.
Authors: Blache Celine A. , Hasan Nafis , Park Jeehna , Suh Stephen , Gorenstein David G. , Rui Hallgeir , Tanaka Takemi
Published: August 2014

Solid tumors are multicellular complexes where the tumor stroma that is comprised of endothelial cells, pericytes, fibroblasts and immune cells, all of which orchestrate to assist in cancer cell growth, angiogenesis and invasion. The tissue infiltration of immune cells is mediated by a multistep adhesion cascade and involves the selectin family of calcium-dependent cell surface glycoproteins Among this family, E-selectin (CD62E, ELAM-1 or LECAM-2) is exclusively expressed on the surface of endothelial cells in a highly inducible manner in response to inflammatory cytokines, and consequently an elevated E-selectin expression has been reported in many types of diseases including cancer. Endothelial E-selectin (eE-sel) assists in the initial adhesion of circulatory leukocytes to the surface of vascular endothelium by interacting with its ligands (sLeX, sLeA and CD44). The external domain of E-selectin can be cleaved off and shed into the circulation as soluble E-selectin (sE-sel). sE-sel is present in the serum of cancer patients and is associated with occurrence of metastases and poor survival in breast and colorectal cancers. However, the biological relevance of sE-sel is not clearly understood. In this study, we aim to identify the biological role of sE-sel in breast cancer growth. We have demonstrated that sE-sel enhances the adhesion and tissue migration of leukocytes into breast tumor both in vitro through the activation of PI3 kinase and its downstream signaling cascade. We have also demonstrated that 7 times more peripheral blood mononuclear cells (PBMC) migrate into breast tumor when pre-incubated with sE-sel as compared to untreated condition. Therefore, we conclude that sE-sel serves as a chemoattractant that enhances the tissue migration of leukocytes, which lead to the development of solid tumor stroma that enhances the growth of breast tumor and invasion.

Citation Format: Celine A. Blache, Nafis Hasan, Jeehna Park, Stephen Suh, David G. Gorenstein, Hallgeir Rui, Takemi Tanaka. A novel role of soluble E-selectin as a chemoatractant to human leukocytes through the PI3kinase signaling pathway in breast cancer. [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 4992. doi:10.1158/1538-7445.AM2013-4992
Abstract 50: Anchored multiplex PCR for detection of gene rearrangements and mutations using next-generation sequencing.
Authors: Zheng Zongli , Zhelyazkova Boryana , Panditi Divya , Robinson Hayley , Engelman Jeffrey A. , Iafrate John A. , Le Long
Published: August 2014

We describe a rapid targeted RNA-seq library construction method for the detection of gene fusions in cancer using next generation sequencing. The method involves ligation of half-functional sequencing adaptors to double strand cDNA, followed by two successive PCR reactions using hemi-nested gene-specific 3’ primers with the 5’ adaptor primer, and generates libraries ready for bi-directional sequencing. RNA extracted from formalin-fixed paraffin-embedded biopsies can be used directly without the need to deplete ribosomal RNA, non-target mRNA or genomic DNA. Importantly, the assay can be performed without the need to know the 5’ partner in a gene fusion event. The method can also be applied to genomic DNA for detection of gene mutations, insertions, deletions and copy number changes. The method is very flexible and can allow multiplexing of over 500 targets. We have designed a lung cancer translocation panel which includes 18 amplicons for detections of gene rearrangements involving ALK, ROS1 and RET. For targeted genomic DNA-seq, we have designed a small 96-amplicon panel including tumor hotspots and entire coding sequences of key tumor suppressor genes TP53 and PTEN, and a 623-amplicon panel for 370 exons of 18 tumor suppressor genes. Unlike conventional PCR-based method, this method generates libraries with random sequencing start sites and allows for direct sequencing without having to spiking in controls (e.g. PhiX) on those platforms where high starting site complexity is required, such as the Illumina Miseq sequencer. The assays generally achieve high on-target specificity (>90%), and are very cost-effective. The targeted RNA-seq assay has detected various gene rearrangements in known FISH-positive cases with previously unknown 5’ partners using our archived samples. The small 96-amplicon genomic DNA assay showed 100% of targeted bases having >100-fold coverage and 99.9% having >500-fold coverage with minimal optimization. In our first attempt of targeting 370 exons (626 amplicons, target size 52.3 kilobases), this assay achieved 97% of targeted bases having >100-fold coverage and 93% having >500-fold using ¼ of a Miseq sequencing run.

Citation Format: Zongli Zheng, Boryana Zhelyazkova, Divya Panditi, Hayley Robinson, Jeffrey A. Engelman, John A. Iafrate, Long Le. Anchored multiplex PCR for detection of gene rearrangements and mutations using next-generation sequencing. [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 50. doi:10.1158/1538-7445.AM2013-50
Abstract 5009: Stem cells and their signals during skin tumor regression.
Authors: Zito Giovanni , Saotome Ichiko , Greco Valentina
Published: August 2014

Basic mechanisms of tissue development and regeneration are often hijacked during Cancer. A subset of skin squamous cell carcinoma is known to be able to spontaneously self-regress. These tumors are commonly referred as Keratoacanthoma and thought to arise from the skin hair follicle. Because skin hair follicles undergo continuous growth and regression, we hypothesized that the molecular mechanisms that regulate hair follicle regression drive Keratoacanthoma self-regression. In order to test this hypothesis we ask 1) what is the cellular origin of Keratoacanthoma, 2) and what signaling mechanisms are responsible for Keratoacanthoma self-regression.

First, in order to understand the cellular origin of Keratoacanthoma, we utilize a genetic lineage tracing approach in combination with a DMBA-based chemical carcinogenesis protocol that recapitulates human Keratoacanthoma growth and self-regression in mice. Given that the location and identity of hair follicle stem cells has been identified, we utilize a spatially restricted Tamoxifen inducible CreER mouse line that specifically label hair follicle stem cells and their descendants (K19CreER;GFPr). By these means, we found that GFP labeled cells are observed within Keratoacanthoma tumors, thus suggesting that hair follicle stem cells contribute to the development of the self-regressing Keratoacanthoma tumors. Second, in order to identify the molecular mechanisms that drive Keratoacanthoma self-regression, we use a parallel approach of both human and mouse transcriptional analysis of Keratoacanthoma during either growth or regression. By focusing on signaling pathways that regulate hair follicle regression, we found that Wnt signaling is switched off during Keratoacanthoma self regression in both human and mouse Keratoacanthomas by immunofluorescence and real time PCR approaches. We are currently testing 1) whether Wnt is sufficient and/or required for Keratoacanthoma regression behavior and 2) what is upstream of Wnt down-regulation during the regression phase by genetic and sequencing approaches.

The identification of the cells and signals that regulate Keratoacanthoma tumor growth and regression will provide key clues on the relevant cell populations and signaling that will likely be proper targets in other tumors beyond Keratoacanthomas, and allow for the design of treatment strategies that exploit stem cell regression pathways to switch off stem cell populations in cancerous tissues.

Acknowledgements: New York Stem Cell Foundation (NYSCF) Postdoctoral Fellowship Grant (GZ) and ACS grant #121966-RSG-12-059-01-DDC (VG).

Citation Format: Giovanni Zito, Ichiko Saotome, Valentina Greco. Stem cells and their signals during skin tumor regression. [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 5009. doi:10.1158/1538-7445.AM2013-5009
Abstract 5065: Orally active nontoxic dual MMP2 and CAIX inhibitors as anticancer therapy.
Authors: Breuer Eli
Published: August 2014

Carbonic anhydrases IX and XII, (CAIX and CAXII) are critical to maintain a low pH in the tumor cell's microenvironment, and MMP-2 is critical for breaching the basement membrane that opens the way to the dissemination of metastases. The expression of carbonic anhydrase IX (CAIX), a marker for hypoxic tumors, is correlated with poor prognosis. In this presentation, we wish to report that carbamoylphosphonates (CPOs) have been identified as orally bioavailable dual inhibitors of matrix metalloproteinase-2 (MMP-2) on the one hand, and carbonic anhydrases (CAs) on the other hand, especially the IX and XII isoforms, well known as cancer promoting factors. We have also demonstrated that the ionized CPO acids are unable to cross the cell membrane and thus are limited to interact with enzymes present in the extracellular domains of as are both CA isozymes CAIX and CAXII and MMP-2. Finally, exposing cancer cells to CPOs in hypoxic conditions resulted in the dose dependent release of lactate dehydrogenase, confirming the direct interaction of the CPOs with the cancer related isozymes CAIX and XII and thereby promoting cellular damage. Thus, CPOs can be regarded as novel orally active nontoxic drug candidates for CAIX expressing tumor targeted chemotherapy acting by two synergistic mechanisms, namely, inhibiting CAs and MMPs simultaneously.

Citation Format: Eli Breuer. Orally active nontoxic dual MMP2 and CAIX inhibitors as anticancer 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 5065. doi:10.1158/1538-7445.AM2013-5065
Abstract 5069: Engineering TIMP-1 for selective MMP inhibition and future use as a protein therapeutic.
Authors: Mehner Christine , Batra Jyotica , Robinson Jessica , Radisky Derek C. , Radisky Evette S.
Published: August 2014

Matrix metalloproteinases (MMPs), a family of extracellular matrix degrading proteins, have been found to be upregulated in many human cancers and have been shown to contribute to cancer progression. There have been many aborted attempts to target MMPs therapeutically using small molecule inhibitors; the limited selectivity of most MMP inhibitors may be a major factor contributing to their poor effectiveness. As an alternative to small molecule MMP inhibitors, we are developing new methodology to create selective protein inhibitors of MMPs, based on the scaffold of the natural inhibitor TIMP-1, that may be used as protein therapeutics. Because TIMP-1 has a very short plasma half-life, we have developed methods for PEGylation that extend the plasma half-life to about 24h while preserving MMP inhibitory activity, rendering it more suitable for in vivo applications. We have also generated mutations in TIMP-1 that confer selective binding toward particular MMPs. The targets thus far pursued include MMP-9, MMP-3, and MMP-10, which represent therapeutic targets of interest in breast cancer and lung cancer. In the future, the methods developed here can be used to identify TIMP-1 variants selective toward additional MMPs, which may be of utility in the research and treatment of many human cancers.

Citation Format: Christine Mehner, Jyotica Batra, Jessica Robinson, Derek C. Radisky, Evette S. Radisky. Engineering TIMP-1 for selective MMP inhibition and future use as a protein therapeutic. [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 5069. doi:10.1158/1538-7445.AM2013-5069
Abstract 5095: Biochanin A, a natural isoflavone inhibits angiogenesis in glioma.
Authors: Jain Aditi , Lai James C.K. , Bhushan Alok
Published: August 2014

Malignant gliomas like glioblastoma multiforme are the most lethal form of adult brain tumor. Patients with this disease survive for only 12-15 months after diagnosis. Angiogenesis, a process of formation of new blood vessels is a pathological hallmark of glioblastoma and plays an important role in tumor growth and survival. Although angiogenesis holds promise as a drug target, recent studies have highlighted that glioblastoma acquires aggressive invasive characteristics when treated with anti-angiogenic monotherapy. Therefore, there is an urgent demand for therapies which effectively target angiogenesis and limit invasion in glioblastoma. Previously, our laboratory has found that biochanin A, a dietary isoflavone inhibits invasion in human glioblastoma cells. In this study, we determined the effects of biochanin A on brain tumor angiogenesis using rat brain tumor cells (C6) and endothelial (bEnd.3) cells. Our cell survival data indicate a dose dependent decrease in cell survival of both C6 and bEnd.3 cells treated with biochanin A (5μM-70μM) for 72 hours. Biochanin A also inhibited ERK and AKT pathway in these cells. Zymography invasion assay demonstrated a decrease in enzymatic activity of MMP's in biochanin A treated C6 and bEnd.3 cells. Apart from these signaling molecules, angiogenesis is also driven by hypoxia through upregulation of hypoxia inducible factor (HIF-1α) which releases vascular endothelial growth factor (VEGF), a key player of angiogenesis. We found that biochanin A at 35 μM inhibited protein expressions of both HIF-1α and VEGF in C6 cells treated with cobalt chloride, a chemical inducer of hypoxia. Biochanin A was also effective in inhibiting angiogenesis in an ex vivo chick chorioallantoic membrane model. These findings indicate that we may use biochanin A as a dual targeted agent that inhibits two processes, invasion and angiogenesis at similar concentrations. Thus, our study will allow the formulation of new and improved therapies for glioblastoma and ultimately enhance patient survival. (This study was supported by NIH INBRE grant #P20R16454, University Research Committee grant and Mountain States Tumor and Medical Research Institute grant).

Citation Format: Aditi Jain, James C.K. Lai, Alok Bhushan. Biochanin A, a natural isoflavone inhibits angiogenesis in glioma. [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 5095. doi:10.1158/1538-7445.AM2013-5095
Abstract 5102: Analysis of CTCs enriched from whole blood samples of Breast, Lung and Colorectal cancer patients with a flexible microspring array device.
Authors: Harouaka Ramdane , Zhou Ming-Da , Yeh Yin-Ting , Truica Cristina , Das Avisnata , Kaifi Jussuf , El-Deiry Wafik , Liu Xin , Belani Chandra , Baney Tara , Allerton Jeffrey , Zheng Si-Yang
Published: August 2014

The process by which metastatic cancers release cells that detach from a primary tumor, spread through the circulatory system and invade distant organs accounts for over 90% of cancer related deaths. A fundamental challenge with analysis of these circulating tumor cells (CTCs) in blood samples is the fact that they are so rare, with only a few tumors cells occurring among billions of blood cells. We have developed a flexible micro spring array (FMSA) that employs mechanical separation to effectively enrich CTCs in a nondestructive manner that does not compromise cell viability. The FMSA device geometric design and applied filtration pressures have been optimized to maximize capture efficiency, enrichment against leukocytes, and tumor cell viability. We have successfully enriched and detected varying numbers of CTCs (min=1, max=101) in 7.5mL whole blood samples obtained from Breast, Lung and Colorectal cancer patients. CTCs were analyzed qualitatively and quantitatively based on immunocytochemical determination of phenotype and cell morphological characteristics. Aggregate clusters of cells were observed in all assayed cancer types that comprised of multiple attached CTCs (min=2, max=20) and occasionally leukocytes as well.

Citation Format: Ramdane Harouaka, Ming-Da Zhou, Yin-Ting Yeh, Cristina Truica, Avisnata Das, Jussuf Kaifi, Wafik El-Deiry, Xin Liu, Chandra Belani, Tara Baney, Jeffrey Allerton, Si-Yang Zheng. Analysis of CTCs enriched from whole blood samples of Breast, Lung and Colorectal cancer patients with a flexible microspring array device. [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 5102. doi:10.1158/1538-7445.AM2013-5102
Abstract 5131: Modeling of EMT/MET transitions in breast cancer stem cells.
Authors: Sehl Mary E. , Shimada Miki , Lange Kenneth , Wicha Max S.
Published: August 2014

Background: Recent studies suggest that breast cancer stem-like cells (BCSCs) exist in two freely interconvertible states: an EMT- and an MET-like state, and that conversion between these two states is regulated by both intracellular and microenvironmental signaling (Liu et al. 2012, Korkaya et al. 2012). Using a mathematical model, we quantify rates of transition between the EMT and MET-like states. We further explore BCSC behavior in response to alterations in microenvironmental signaling and examine key regulators of BCSC population dynamics.

Methods: We employ a continuous-time Markov chain model to quantify rates of transition between the EMT and MET-like state for BCSCs. Our data-based modeling approach employs parameter estimates derived from mouse xenograft experiments from the Wicha laboratory (Liu et al. 2012) to estimate the equilibrium EMT- and MET-like state distributions. We expand our model to simulate BCSC population counts and EMT and MET state transitions in response to alterations in the complex regulatory network involving IL-6, HER2, miRNA, NF-κB, and TGF-β signaling.

Results: We estimate the rate of BCSC transition from an EMT- to MET-like state to be 0.08 per cell per day, and the rate of transition from an MET- to EMT-like state to be 0.013 per cell per day. Simulation studies examining the effects of abrogating microenvironmental signals individually and in combinations revealed that slowing both self-renewal rate and the rate of transition from an MET- to EMT-like state is essential to eradicating the total BCSC population. The fastest decline in the BCSC population was observed when IL-6 is inhibited and the activation of NF-κB via HER2 signaling and IL-6 feedback was blocked.

Conclusions: Rates of transition between EMT- and MET-like states are estimated to occur frequently and these events are much more likely than dedifferentiation. Predictions from our mathematical model match experimental data (Korkaya et al. 2012) showing the efficacy of combined HER2 and IL-6 blockade in reducing the BCSC population.

Citation Format: Mary E. Sehl, Miki Shimada, Kenneth Lange, Max S. Wicha. Modeling of EMT/MET transitions in breast cancer stem cells. [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 5131. doi:10.1158/1538-7445.AM2013-5131
Abstract 5132: Interactively exploring patterns in TCGA data: a web-based compendium of ‘next-generation’ clustered heat maps.
Authors: Weinstein John N. , Kane David W. , Akbani Rehan , Dodda Deepti , Nguyen Lam , Ryan Michael C. , Wakefield Chris , Broom Bradley M.
Published: August 2014

Each of the 5 TCGA marker paper published in Nature to date has included at least one clustered heat map (CHM). We introduced CHMs in the early 1990’s for pharmacogenomic analysis (1) and later for integrated visualization of genomic, transcriptomic, proteomic, pharmacological, and functional data (1). As the ubiquitous first-order way of visualizing omic data, CHMs have appeared in many thousands of publications (3–9), including those from TCGA. We have elsewhere summarized their limitations (10).

One such limitation is that CHMs are generally static images. We therefore initiated the next-generation CHM (NG-CHM) project, using an image-tiling technology similar to that in Google Maps for navigation and extreme drill-down without loss of resolution. Once the CHM has been zoomed sufficiently, labels (e.g., gene, protein, or drug names) appear on the image's axes. Clicking on a label produces a menu of link-outs (e.g., to GeneCards, Google, PubMed). For gene vs. gene maps, each pixel can represent a color-coded Pearson correlation coefficient. Clicking on the pixel pulls up the corresponding data scattergram, bootstrap statistics, literature references, or pathway relationships. Strong usability features include floating windows, flexible search tools, cluster selection tools, customizable re-coloring of the CHM, and high-quality PDF's suitable for publication. NG-CHMs are a major resource for exploratory analysis and visualization in multiple projects of TCGA and other large-scale molecular profiling programs. Explore interactive versions for TCGA breast, colorectal, lung squamous, and glioblastoma data at http://bioinformatics.mdanderson.org/main/TCGA/NGCHM.

Supported in part by NCI Grant No. U24CA143883, by a gift from the Mary K. Chapman Foundation, and by a grant from the Michael and Susan Dell Foundation honoring Lorraine Dell.

Citation Format: John N. Weinstein, David W. Kane, Rehan Akbani, Deepti Dodda, Lam Nguyen, Michael C. Ryan, Chris Wakefield, Bradley M. Broom. Interactively exploring patterns in TCGA data: a web-based compendium of ‘next-generation’ clustered heat maps. [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 5132. doi:10.1158/1538-7445.AM2013-5132
Abstract 5156: Upstream activation of PTEN.
Authors: Naguib Adam , Bencze Gyula , Faehnle Christopher R. , Schalch Thomas , Lazar Zsolt , Ruse Cristian I. , Joshua-Tor Leemor , Pappin Darryl J. , Trotman Lloyd C.
Published: August 2014

The PTEN tumor suppressor is among the most frequently altered genes of cancer. PTEN suppression at the protein level is critically associated with disease since PTEN is haploinsufficient in many cancer types, including prostate. We have recently shown strong cooperation between protein phosphatases and PTEN to suppress PI 3-Kinase and AKT signaling in prostate cancer. Intriguingly, our findings showed that PTEN status orchestrates a PHLPP2 response by controlling the protein levels of this phosphatase.

Yet, little is known about genes that control the levels and activity of PTEN to a degree that they critically maintain its function in disease. Therefore, it is assumed that PTEN is constitutively active in normal cells.

Here we identify the upstream activation mechanism of PTEN and discuss the consequences for cancer diagnosis and therapy with PI 3-Kinase pathway inhibitors.

Citation Format: Adam Naguib, Gyula Bencze, Christopher R. Faehnle, Thomas Schalch, Zsolt Lazar, Cristian I. Ruse, Leemor Joshua-Tor, Darryl J. Pappin, Lloyd C. Trotman. Upstream activation of PTEN. [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 5156. doi:10.1158/1538-7445.AM2013-5156
Abstract 5171: FATS is an E2-independent ubiquitin ligase that stabilizes p53 and promotes p53-dependent checkpoint response.
Authors: Li Zheng , Yan Shuangshuang , Qiu Li , Zhang Jun , Ma Ke , Zhang Xifeng , Hao Xishan
Published: August 2014

Ubiquitin linkage is critical in directing the cellular fate of a ubiquitinated protein. Although K48-linked polyubiquitination of p53 leads to its degradation, whether polyubiquitination of p53 has a positive role in its activation remains unknown. Here, we show that FATS, a cancer-associated gene susceptible to DNA damage, acts as a p53 activator through binding to p53 and polyubiquitnating p53. Knockdown of FATS impairs p53 activation in response to DNA damage. Moreover, FATS is a unique ubiquitin ligase (E3) that assembles non-linear ubiquitin chains through K11-, K29- and K63-linkages, independently of ubiquitin-conjugating enzyme (E2). The expression of NH2-terminal FATS is sufficient to polyubiquitinate and stabilize p53, which is associated with increased transcriptional activity of p53 and stronger effect on p53-mediated cell cycle arrest. Importantly, FATS-catalyzed polyubiquitination of p53 is required for robust activation of p53 upon DNA damage. Our findings uncover a new mechanism of p53 activation in response to DNA damage and establish the functional linkage between non-linear polyubiquitination and checkpoint response.

Citation Format: Zheng Li, Shuangshuang Yan, Li Qiu, Jun Zhang, Ke Ma, Xifeng Zhang, Xishan Hao. FATS is an E2-independent ubiquitin ligase that stabilizes p53 and promotes p53-dependent checkpoint response. [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 5171. doi:10.1158/1538-7445.AM2013-5171
Abstract 5182: MSP58 regulates telomerase activity and cell proliferation via interaction with TEIF.
Authors: Hsu Che-Chia
Published: August 2014

Telomerase expression is essential for cell proliferation and survival, which also plays a role in development, senescence and cancer. In our previous studies, we demonstrated that ectopic expression MSP58 regulates cell proliferation in context-dependent manner and induces premature senescence in HT1080 cells and normal human diploid fibroblasts through p53/p21 senescence pathway. In addition, we also demonstrated that MSP58 overexpression significantly suppressed telomerase activity in HT1080 cells. Currently, we identified a novel MSP58 interacting protein, TEIF (Telomerase transcription element-interacting factor) by yeast-two hybrid screening. TEIF has been reported to up-regulate the hTERT gene expression and telomerase activity. Interestingly, we found that MSP58 represses the TEIF-mediated activation of telomerase. Furthermore, overexpression of MSP58 represses TEIF promoted anchorage-independent growth in HT1080 cells. In contrast, knockdown MSP58 expression increases TEIF promoted anchorage -independent growth in HT1080 cells. These results suggest that MSP58 regulates telomerase activity via interaction with TEIF and contributes to control cell proliferation.

Citation Format: Che-Chia Hsu. MSP58 regulates telomerase activity and cell proliferation via interaction with TEIF. [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 5182. doi:10.1158/1538-7445.AM2013-5182
Abstract 5187: The membrane traffic regulator PACS-1 mediates genome stability at S-phase of the cell cycle.
Authors: Veena Mysore S. , Basak Saroj K. , Venkatesan Natarajan , Zinabadi Alborz , Thomas Laurel , Thomas Gary , Srivatsan Eri S.
Published: August 2014

We previously mapped a 5.5 kb homozygous deletion in cervical cancer cell lines and primary tumors to chromosome 11q13 within the 1st intron of PACS-1 gene, which encodes a membrane traffic regulator. This deletion correlates with elevated expression of 120 kDa PACS-1 in primary cervical tumors compared to normal tissues as well as the expression of a 140 kDa immunoreactive isoform in the nucleus specifically in cervical cancer cell lines. Inspection of the PACS-1 mRNA sequence revealed a target site for miR449a, which mediates cell fate. Northern blot analysis showed miRNA 449a expression was reduced in cervical cancer cell lines and primary tumors suggesting that dysregulation of miRNA449a or the intronic deletion contributed to aberrant PACS-1 expression and that the increased expression of PACS-1 may mediate cell viability and cell cycle progression. Consistent with this possibility, siRNA knockdown of PACS-1 or increased expression of miR449a caused cells to accumulate in S phase and induced expression of γH2AX. By contrast, overexpression of PACS-1 or expression of antimiR 449a reduced γH2AX expression. Whereas PACS-1 mediates secretory pathway trafficking, the effect of PACS-1 expression on genome stability suggested PACS-1 might shuttle between the cytoplasm and the nucleus to mediate genome stability. Consistent with this possibility, the PACS-1 sequence contains canonical NLS and NES motifs. Indeed, confocal microscopy studies revealed GFP-tagged PACS-1 accumulated in the nucleus in a leptomycin B-dependent manner. We hypothesize that aberrant expression of PACS-1 in cervical cancer cells results in the stabilization and replication of rearranged DNA sequences leading to tumor development.

Citation Format: Mysore S. Veena, Saroj K. Basak, Natarajan Venkatesan, Alborz Zinabadi, Laurel Thomas, Gary Thomas, Eri S. Srivatsan. The membrane traffic regulator PACS-1 mediates genome stability at S-phase of the cell cycle. [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 5187. doi:10.1158/1538-7445.AM2013-5187
Abstract 519: Attenuation of mammary tumor growth by gap junction enhancer.
Authors: Shishido Stephanie N. , Nguyen Thu A.
Published: August 2014

Normal cells have functional gap junctional intercellular communication (GJIC), while cancer cells exhibit many defects in cellular communication that contribute to the loss of tissue homeostasis. It is believed that restoring GJIC is linked to drug sensitivity and reduction of tumorigenicity. Previous studies show that GJIC and neoplastic cellular growth are inversely related and small molecule targeting gap junction can alter tumor growth. A dose of 25 mg/kg gap junction enhancer (PQ) can cause a 77% decrease of xenograft T47D breast tumors. In addition these small molecules can induce a decrease of tumor growth by 110%, 129%, and 73% in the pre, early, and late stages of tumor development of the transgenic mouse strain, FVB/N-Tg(MMTV-PyVT)634Mul/J. Western blot analysis shows that the gap junction protein, Cx43, was highly expressed in the PQ-treated tumors compared to the controls. Data suggests that enhancement of GJIC attenuates tumor growth; specifically Cx43 plays a significant role in tumorigenesis. Establishment of a continuous line of mammary tumor cells from the malignant neoplasm of a female transgenic mouse demonstrates that PQs can cause an increase of Cx43 expression and subsequently trigger a decrease of cell viability. Overall, targeting gap junction by small molecule PQ has shed light to the dynamic of connexins and gap junctions in mammary tumors.

Citation Format: Stephanie N. Shishido, Thu A. Nguyen. Attenuation of mammary tumor growth by gap junction enhancer. [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 519. doi:10.1158/1538-7445.AM2013-519