bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 5151: Enhanced chemotactic response of MDA-MB-231 breast cancer cells towards stable gradients of EGF
Authors: Baumann Nina , Kuttenberger Verena , Huemmer Christine , Schwarz Jan , Horn Elias Horn , Zantl Roman
Published: August 2018

Chemotactic cell migration is a basic mechanism underlying cancer cell invasion and hence metastasis. In this regard, growth factors such as epidermal growth factor (EGF) have been identified as guidance cues. Using ibidi's µ-Slide Chemotaxis we confirm the growth factor EGF as potent guidance cue for directional MDA-MB-231 migration in a physiological 3D environment. Moreover, we find enhanced sensitivity towards gradients of EGF in serum free media supplemented with defined protein composition (UltraCULTURETM). Combining defined, physiological migration conditions and enhanced sensitivity allowed us to quantify EGF dependent MDA-MB-231 chemotaxis in a detailed manor. MDA-MB-231 cells showed increased directional and kinetic response towards temporal and stable spatial gradients of EGF. While EGF guided directional migration was highly concentration dependent with a concentration optimum of 10 ng/mL, we found the chemokinetic effect induced by the presence of EGF being concentration independent. Those results suggest differential response of the migration and signal interpretation machinery of MDA-MB-231 cells. Both, blocking the ligand binding domain of the EGF-Receptor (EGFR) by a blocking antibody and inhibition of the kinase domain of EGFR by a small molecule inhibitor (AG1478) led to a reduction in EGF induced directional sensing and migration velocity. Additionally, low, non-effective single doses of antibody and small molecule inhibitor showed synergistically effective inhibition if combined. Those results support EGF being a potent guidance cue for MDA-MB-231 cell migration and help to understand the mechanisms behind chemotactic migration driven cancer metastasis.

Citation Format: Nina Baumann, Verena Kuttenberger, Christine Huemmer, Jan Schwarz, Elias Horn Horn, Roman Zantl. Enhanced chemotactic response of MDA-MB-231 breast cancer cells towards stable gradients of EGF [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5151.
Abstract 5156: RhoC decreases tight junction stabilization in breast cancer cells, revealing a potential therapeutic target
Authors: Cheriyan Hannah , Wu Zhi-Fen , Yates Joel , Merajver Sofia D.
Published: August 2018

RhoC, a member of the Rho GTPase family, has been shown to have a role specifically in facilitating metastasis of breast cancer cells1, however no conclusive mechanism for how RhoC promotes metastasis currently exists. We demonstrate that CRISPR-Cas9 knockout of RhoC in SUM149 and MDA-MB231 cells results in increased epithelial morphology, cell-cell connections, and tight junction marker (ZO-1, occludin, PATJ/PALS1/CRB3) colocalization compared to wild type cells, as studied via immunofluorescent staining. These results suggest that high expression of RhoC in cancer cells destabilizes tight junctions, which could allow for the increased metastatic potential observed with RhoC-overexpressing cells in prior studies2-4. Ongoing work investigates whether these morphological and molecular changes are observed in other breast cancer cell lines, such as SUM190 and VARI-068, a low-passage PDX-derived triple negative breast cancer cell line. Furthermore, we will determine whether RhoC knockout in these cells lines actively modulates tight junction stability as measured via transepithelial electrical resistance (TEER). Taken together, these data support an important role for RhoC in tight junction modulation, thereby revealing a potential highly specific new therapeutic target in RhoC-driven metastases control.

References

1. Hakem, A. et al. RhoC is dispensable for embryogenesis and tumor initiation but essential for metastasis. Genes Dev. 19, 1974-1979 (2005).

2. van Golen, K. L., Wu, Z. F., Qiao, X. T., Bao, L. W. & Merajver, S. D. RhoC GTPase, a novel transforming oncogene for human mammary epithelial cells that partially recapitulates the inflammatory breast cancer phenotype. Cancer Res. 60, 5832-8 (2000).

3. van Golen, K. L., Wu, Z. F., Qiao, X. T., Bao, L. & Merajver, S. D. RhoC GTPase overexpression modulates induction of angiogenic factors in breast cells. Neoplasia 2, 418-25 (2000).

4. Wu, M., Wu, Z. F., Rosenthal, D. T., Rhee, E. M. & Merajver, S. D. Characterization of the roles of RHOC and RHOA GTPases in invasion, motility, and matrix adhesion in inflammatory and aggressive breast cancers. Cancer 116, 2768-2782 (2010).

Citation Format: Hannah Cheriyan, Zhi-Fen Wu, Joel Yates, Sofia D. Merajver. RhoC decreases tight junction stabilization in breast cancer cells, revealing a potential therapeutic target [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5156.
Abstract 5164: Mechanosensor MYL9 regulates cancer cell malignancy in gastrointestinal tumors
Authors: Konno Masamitsu , Yanagisawa Kiminori , Matsushita Katsunori , Asai Ayumu , Koseki Jun , Matsusaki Michiya , Deguchi Shinji , Doki Yuichiro , Mori Masaki , Ishii Hideshi
Published: August 2018

Although the stiffness of tissues likely is involved in the malignant behavior of tumors, it remains to be clarified which molecules control the nature, how it is involved in the invasiveness of tumors, or whether any marker is available for the prediction of cancer patient prognosis. In the present study, we studied the role of Myl9, a non-muscle-type, myosin light chain by the experiment in vitro, and assessed the usefulness in the stratification of patients in vivo as the precision medicine. Given that Myl9 is involved in the contraction of cell skeleton, cell hardness, and alterations of cell morphology in various tissues, we first examined whether the expression of the Myl9 is associated with the clinical status of tumors by immunohistochemistry. The results of 45 cases with colon cancer and pancreatic cancer indicated that the increased expression of Myl9 is associated significantly with a reduced provability of overall survival and disease-free survival of those cancers. Moreover, we noted the differential expression of Myl9 in epithelial cancer cells and mesenchymal fibroblasts, i.e., the accumulation of Myl9 staining in cell nuclei of fibroblasts. The experiment of 3-dimensional culture with cancer cells and fibroblasts confirmed the results. Furthermore, we investigated whether Myl9 overexpression is involved in the biologic behavior of gastrointestinal cancer cells. The results showed that the rentiviral-mediated overexpression of Myl9 resulted in an increase of cell proliferation and invasion as well as tumorigenicity in mice. The present study indicates that Myl9 protein can play a fundamental role in the malignant behaviors of gastrointestinal cancer cells.

Citation Format: Masamitsu Konno, Kiminori Yanagisawa, Katsunori Matsushita, Ayumu Asai, Jun Koseki, Michiya Matsusaki, Shinji Deguchi, Yuichiro Doki, Masaki Mori, Hideshi Ishii. Mechanosensor MYL9 regulates cancer cell malignancy in gastrointestinal tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5164.
Abstract 5170: The effect of vitamin K on aggressiveness, lipid metabolism and gene expression in triple-negative breast cancer cells
Authors: Kokabee Leila , Beaudin Sarah , Welsh JoEllen
Published: August 2018

Vitamin K is an essential cofactor in the γ-carboxylation of glutamate (Glu) to γ-carboxyglutamate (Gla), a post-translational modification mediated by the gamma-glutamyl carboxylase enzyme (GGCX) and vitamin K oxidoreductases (VKORC1 or VCORC1L1). All three of these genes are expressed in most breast cancer cell lines and The Cancer Genome Atlas (TCGA) data indicate that upregulation of these genes is associated with reduced survival in breast cancer patients. Since vitamin K is not typically present in cell culture media, γ-carboxylation is limited in vitro despite the presence of GGCX and VKORs. To determine the functional significance of the vitamin K pathway in breast cancer cells, we assessed the effect of vitamin K treatment on cell survival, migration and mammosphere formation. SUM159 and Hs578T cells were maintained in vitamin K1 (5 ug/mL) for at least 3 passages for all assays. Cells passaged with vitamin K produced γ-carboxylated proteins and exhibited increased cell survival after 72h, increased mammosphere formation after 8 days and increased cell migration after 48h compared to cells passaged in ethanol vehicle. Inhibition of VKORC1 with 2 uM warfarin decreased the production of γ-carboxylated proteins and reduced the effects of vitamin K on cell survival and migration but not on mammosphere formation. Microarray profiling and pathway analysis indicated upregulation of several known oncogenic pathways, including PI3K-AKT, VEGF-VEGFR, RANK-RANKL and JAK/STAT in vitamin K-treated SUM159 and Hs578T cells. Thus, γ-carboxylation of proteins driven by vitamin K might indirectly activate these pathways to enhance cell survival, cell migration and mammosphere formation. Additional pathways upregulated in vitamin K-treated cells included adipogenesis, fatty acid biosynthesis and lipid metabolism. We therefore examined lipid droplet formation in cells exposed to vitamin K using Bodipy assays. We detected an increase in lipid droplet formation after 72 hours of vitamin K treatment, which was inhibited by warfarin. Since aggressive breast cancers are often associated with accumulation of cytoplasmic lipid droplets, further studies on the mechanism by which vitamin K increases lipid accumulation are warranted. In conclusion, our data indicate that vitamin K enhances γ-carboxylation, breast cancer aggressiveness and lipid metabolism, suggesting that blocking the vitamin K pathway might be of therapeutic value for patients whose tumors express GGCX and VKORs.

Citation Format: Leila Kokabee, Sarah Beaudin, JoEllen Welsh. The effect of vitamin K on aggressiveness, lipid metabolism and gene expression in triple-negative breast cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5170.
Abstract 5177: Metastasis: Leveraging transcriptomics to identify potential therapeutics
Authors: Ung Matthew , Funt Jason M. , Lysaght Andrew C. , Zhang Jenny , Escalante-Chong Renan , Koytiger Gregory , Kolitz Sarah , Kusko Rebecca , Zeskind Benjamin , Fowler Kevin D.
Published: August 2018

Five-year survival rates for patients whose cancer has metastasized are dramatically lower than for those with localized disease. However, few therapeutic development efforts specifically focus on inhibiting the process of metastasis.

Here we perform a systematic pan-cancer analysis of RNA-seq data from The Cancer Genome Atlas to identify targetable gene expression changes in primary tumors that confer metastatic potential. In 4,844 patients comprising 13 different cancer types, we construct a gene expression signature that captures consistent pan-cancer alterations that differ between primary tumors associated with node-negative disease with no recorded distant metastasis (N0 not M1) and primary tumors from patients with node-positive disease (N1, N2, or N3). In order to identify potential therapeutic targets, we query this metastasis signature against drug-induced transcriptomic signatures from CMAP and LINCS. Among the top candidates is Chembl410456, which modulates the TGFβ and Wnt/β-catenin signaling pathways, among others. Genes upregulated in metastatic primary tumors and downregulated by Chembl410456 include SERPINE1 and TWIST1. We observe that low SERPINE1 and TWIST1 expression also associate with improved prognosis in multiple cancers, including colon adenocarcinoma (p=0.007 and p=0.014, respectively). Other top-ranked drugs also target the TGFβ signaling pathway. To summarize, we leverage public RNA-seq data to identify a pan-cancer metastatic signature that can be interrogated to systematically identify potential therapeutics that target metastasis. Building on this, we pinpoint antimetastasis drug candidates including several with mechanisms of action involving modulation of TGFβ and/or Wnt/β-catenin pathways.

Citation Format: Matthew Ung, Jason M. Funt, Andrew C. Lysaght, Jenny Zhang, Renan Escalante-Chong, Gregory Koytiger, Sarah Kolitz, Rebecca Kusko, Benjamin Zeskind, Kevin D. Fowler. Metastasis: Leveraging transcriptomics to identify potential therapeutics [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5177.
Abstract 5179: Uncovering the signaling landscape controlling breast cancer cell migration identifies splicing PRPF4B as a metastasis driver
Authors: Water Bob van de , Danen Erik , Koedoot Esmee , Rogkoti Maria , Fokkelman Michiel , Devedec Sylvia Le , Martens John , Stoilov Peter , Foekens John
Published: August 2018

Metastasis is the major cause of death in cancer patients and migration of cancer cells from the primary tumor to distant sites is the prerequisite of metastasis formation. Here we applied an imaging-based RNAi phenotypic cell migration screen uing two highly migratory basal breast cancer cell lines (Hs578T and MDA-MB-231 to provide a repository of candidate metastasis drug targets. We screened ~4,200 individual target genes covering most cell signaling components. We discovered 133 and 113 migratory modulators of Hs578T and MDA-MB-231, respectively, of which 45 genes were common denominators of cell migration. Interaction networks of candidate migratory modulators were in common with networks of different clinical breast cancer prognostic and metastasis classifiers. The splicing factors PRPF4B and BUD31 and the transcription factor BPTF were amplified in human primary breast tumors and the expression was associated with metastasis-free survival. Depletion of PRPF4B, BUD31 and BPTF caused primarily downregulation of genes involved in focal adhesion and ECM-interaction pathways. PRPF4B was essential for TNBC cell migration and critical for breast cancer metastasis formation in vivo, making PRPF4B a candidate for further drug development. Our systematic phenotypic screen provides an important repository for signaling determinants that functionally drive cancer cell migration.

Citation Format: Bob van de Water, Erik Danen, Esmee Koedoot, Maria Rogkoti, Michiel Fokkelman, Sylvia Le Devedec, John Martens, Peter Stoilov, John Foekens. Uncovering the signaling landscape controlling breast cancer cell migration identifies splicing PRPF4B as a metastasis driver [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5179.
Abstract 5188: MDM2 and MDMX promote p53-independent initiation of circulating tumor cells from triple negative breast cancers
Authors: Gao Chong , Xiao Gu , Piersiga Ale , Gou Jiangtao , Ogunwobi Olorunseun , Bargonetti Jill
Published: August 2018

Many human breast cancers overexpress the E3 ubiquitin ligase MDM2 and its homolog MDMX. The Cancer Genome Atlas (TCGA) shows that high MDM2 and MDMX expression correlates with both estrogen receptor positive (ER+) and triple negative breast cancer (TNBC) subtypes. Overexpression of MDM2 and MDMX can drive breast cancer progression through molecular pathways that do not require wild-type p53 degradation. ER positive breast cancers often express wild-type p53 but 80% of TNBC express mutant p53 (mtp53). It has not been determined how MDM2 and MDMX expression in different sub-types of breast cancer, with mutant p53, influence proliferation and metastasis. We compared MDM2 and MDMX-dependent biological outcomes for mtp53 expressing ER+ T47D (mtp53 L194F) and TNBC cell type MDA-MB-231 (mtp53 R280K). In the ER+ cells no change was detected for real time cell migration or E-cadherin protein levels when MDM2 was knocked down by stable shRNA expression but cell proliferation was reduced. In support of this in vitro data, these MDM2 knockdown cells tested in an orthotopic xenograft model in NSG mice demonstrated no MDM2-mediated change in primary tumor invasiveness but did show a reduced tumor volume. Importantly, in the TNBC MDA-MB-231 cells, knocking down either MDM2 or MDMX did not reduce cell proliferation in vitro but greatly blocked cell migration. In support of this in vitro data, these MDA-MB-231 cells with either MDM2 or MDMX knockdown in NSG mice did not show a reduced primary tumor volume but showed a significant inhibition of the production of circulating tumor cells (CTCs). Our data shows that in different subtypes of breast cancers, MDM2 and MDMX can promote alternative p53-independent biological outcomes. The estrogen-activated MDM2 strongly promotes cell proliferation while MDM2 and MDMX overexpression in TNBC promotes circulating tumor cells and potentially metastasis. Understanding the alternative p53-independent roles of MDM2 and MDMX in ER+ and triple negative breast cancers will provide insight for the development of MDMs-targeted theranostics.

Citation Format: Chong Gao, Gu Xiao, Ale Piersiga, Jiangtao Gou, Olorunseun Ogunwobi, Jill Bargonetti. MDM2 and MDMX promote p53-independent initiation of circulating tumor cells from triple negative breast cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5188.
Abstract 5199: Microenvironmental control of breast cancer subtype elicited by paracrine platelet-derived growth factor-CC signaling
Authors: Bocci Matteo , Bartoschek Michael , Roswall Pernilla , Pietras Kristian
Published: August 2018

Aim: Breast tumors of the basal-like, hormone receptor-negative subtype, remain an unmet clinical challenge, as patients exhibit the highest recurrence rate, the shortest time to recurrence and the worst overall survival rate due to a paucity of therapeutic targets. Also, as tumors develop, the surrounding microenvironment co-evolves into an activated state through continuous paracrine communication, creating a dynamic signaling circuitry that promotes malignant progression. Thus, novel treatment approaches that also include the targeting of stromal components are urgently required.

Methods: We used experimental mouse models of cancer (transgenic, syngeneic, human cell lines and patient-derived xenografts) for knockout studies and preclinical trials, immunostaining, in vitro assays, western-blot, gene expression analysis and RNA-sequencing, patient cohorts, data mining and bioinformatics analysis.

Results and discussion: We identified a paracrine crosstalk between cancer cells expressing platelet-derived growth factor (PDGF)-CC and cancer-associated fibroblasts (CAFs) expressing the cognate receptors in human basal-like mammary carcinomas. In translational efforts, we found that PDGF-CC expression in the malignant epithelium of breast cancer was associated with a hormone receptor-negative state. We then generated a mouse model to characterise the functional role of PDGF-CC in tumorigenesis. Moreover, we identified and validated factors secreted by CAFs to maintain a basal-like phenotype, e.g. Stanniocalcin (STC)-1, Hepatocyte Growth Factor (HGF) and Insulin Growth Factor Binding Protein (IGFBP)-3. Genetic or pharmacological targeting of PDGF-CC in experimental mouse models resulted in the transcriptional reprogramming and conversion of basal-like breast tumors into a luminal-like state characterised by Estrogen Receptor (ER)-α positivity, that conferred sensitivity to endocrine therapy in previously intrinsically unresponsive tumors.

Conclusions: Specification of the basal-like subtype of breast cancer is under microenvironmental control and therapeutically actionable in order to achieve sensitivity to endocrine therapy. Our work sheds light on previously unknown mechanisms that define breast cancer subtype and has significant therapeutic implications for patients with basal-like breast tumors.

Citation Format: Matteo Bocci, Michael Bartoschek, Pernilla Roswall, Kristian Pietras. Microenvironmental control of breast cancer subtype elicited by paracrine platelet-derived growth factor-CC signaling [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5199.
Abstract 52: A genomic editing approach for purification of viable quiescent cancer cells
Authors: La Ting , Farrelly Margaret , Yan Xu Guang , Yari Hamed , Zhang Yuanyuan , Feng Yuchen , Tabatabaeehatambakhsh Seyed Hessamedin , Liu Tao , Jin Lei , Zhang Xu Dong
Published: August 2018

Recurrent and metastatic cancer lesions often undergo a period of dormancy, which is closely associated with cancer cell quiescence, a state whereby cancer cells exit the cell cycle and are reversibly arrested in G0 phase. Quiescent cancer cells are inherently resistant to cell death and refractory to therapeutic drugs. However, the mechanisms responsible for the resistance remain largely undefined. This is closely associated with the lack of understanding of their biological properties as a consequence of technical hurdles in the isolation and analysis of viable quiescent cells. Nevertheless, it is known that quiescent cells are characteristically negative for the proliferation marker Ki67 and express high levels of the cyclin-dependent kinase (CDK) inhibitor p27. In this study, we developed a CRISPR/Cas9-based system to fuse a green fluorescent protein (EGFP) gene with endogenous CDKN1B, the gene encoding p27, and a red fluorescent protein (mCherry) gene with endogenous MKI67, the gene encoding Ki67 in the genome of human melanoma cells. By using this system, we have successfully isolated viable p27high/Ki67- melanoma cells using fluorescence-activated cell sorting (FACS). The quiescent state of these cells was confirmed by dual nucleic acid staining (DNA with Hoechst-33342, and RNA with Pyronin Y). This approach provides a unique research tool for further characterization of the biological properties of quiescent cells. Comparative RNA-seq and proteomics analyses are being currently carried out to reveal molecular networks involved in regulating cell quiescence, and to identify molecular targets for overcoming resistance of quiescent melanoma cells to treatment.

Citation Format: Ting La, Margaret Farrelly, Xu Guang Yan, Hamed Yari, Yuanyuan Zhang, Yuchen Feng, Seyed Hessamedin Tabatabaeehatambakhsh, Tao Liu, Lei Jin, Xu Dong Zhang. A genomic editing approach for purification of viable quiescent cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 52.
Abstract 5214: Tumor cell-derived complement components C1r and C1s promote growth of cutaneous squamous cell carcinoma
Authors: Riihilä Pilvi , Nissinen Liisa , Farshchian Mehdi , Kallajoki Markku , Kivisaari Atte , Meri Seppo , Grénman Reidar , Peltonen Sirkku , Peltonen Juha , Kähäri Veli-Matti
Published: August 2018

The incidence of cutaneous squamous cell carcinoma (cSCC) is increasing worldwide. We have analyzed the role of complement components C1r and C1s in the progression of cSCC. Analysis of cSCC cell lines (n=8) and normal human epidermal keratinocytes (NHEK)(n=11) with oligonucleotide arrays, RNA-seq and quantitative RT-PCR revealed significantly elevated C1r and C1s mRNA levels in cSCC cell lines. Western blot analysis showed increased production of C1r and C1s in cSCC cells compared to NHEKs. The mRNA levels for C1r and C1s were markedly elevated in cSCC tumors (n=6) compared to normal skin (n=11) in vivo. Immunohistochemical analysis for C1r and C1s revealed strong tumor cell specific expression of C1r and C1s in invasive sporadic cSCCs (n=164) and recessive dystrophic epidermolysis bullosa-associated cSCCs (n=16), whereas the expression of both was clearly lower in cSCC in situ (n=63), in premalignant epidermal lesions (actinic keratoses, n=61), and in normal skin (n=9). Knockdown of C1r and C1s expression with two specific siRNAs inhibited proliferation of cSCC cells and growth of human cSCC xenograft tumors in vivo. These results provide evidence for the role of tumor cell-derived C1r and C1s in the progression of cSCC independently of C1q and identify these serine proteinases as putative therapeutic targets in unresectable and metastatic cSCC.

Citation Format: Pilvi Riihilä, Liisa Nissinen, Mehdi Farshchian, Markku Kallajoki, Atte Kivisaari, Seppo Meri, Reidar Grénman, Sirkku Peltonen, Juha Peltonen, Veli-Matti Kähäri. Tumor cell-derived complement components C1r and C1s promote growth of cutaneous squamous cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5214.
Abstract 5216: Exosome as a vehicle for delivery of membrane protein therapeutics, PH20 for enhanced tumor penetration and anti-tumor efficacy
Authors: yang yoosoo , Hong Yeonsun , Kim Gi Beom , Nam Gihoon , Kim In-san
Published: August 2018

As biochemical and functional studies of membrane protein remain a challenge, there is growing interest in the application of nanotechnology to solve the difficulties of developing membrane protein therapeutics. Exosome, composed of lipid bilayer enclosed nano-sized extracellular vesicles, is a successful platform for providing a native membrane composition. Here, we report an enzymatic exosome, which harbors native PH20 hyaluronidase (Exo-PH20), was able to penetrate deeply into tumor foci via hyaluronan degradation, allowing tumor growth inhibition and increased T cell infiltration into the tumor. This exosome-based strategy was developed to overcome the immunosuppressive and anti-cancer therapy-resistant tumor microenvironment, which is characterized by an overly accumulated extracellular matrix. Notably, our engineered exosome with the native GPI-anchored form of hyaluronidase had a higher enzymatic activity than a truncated form of the recombinant protein. In addition, the exosome-mediated co-delivery of PH20 hyaluronidase and a chemotherapeutic (doxorubicin) efficiently inhibited tumor growth. This exosome is designed to degrade hyaluronan along the path of its movement, thereby augmenting nanoparticle penetration and drug diffusion. Our results thus show that this is a promising exosome-based platform that harbors not only a membrane-associated enzyme with high activity but also therapeutic payloads.

Citation Format: yoosoo yang, Yeonsun Hong, Gi Beom Kim, Gihoon Nam, In-san Kim. Exosome as a vehicle for delivery of membrane protein therapeutics, PH20 for enhanced tumor penetration and anti-tumor efficacy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5216.
Abstract 5229: Expression and regulation of chondroitin sulfate in prostate cancer
Authors: Nakouzi Nader Al , Wang Chris Kedong , Nelepcu Irina , Crouzit Coralie , Nabavi Noushin , Almami Amal , Oo Htoo Zarni , Clausen Thomas Mandel , Gustavsson Tobias , Salanti Ali , Daugaard Mads
Published: August 2018

Increased levels of chondroitin sulfate (CS) glycosaminoglycans (GAGs) in prostate cancer (PC) have been observed for more than three decades. In 1984, De Klerk et al. noted that hyperplastic and cancerous prostate contained elevated levels of CS while other GAGs, like heparin sulfate (HS), were decreased. Chondroitin sulfate-modified proteoglycans (CSPGs), such as versican or tomoregulin (TENB2), have been promoted as PC progression markers. They have been associated with cell attachment to the matrix, the metastatic phenotype, disease progression, and androgen independence. Functionally, pericellular enrichment of CSPGs in the PC microenvironment promotes cell motility. Our team has discovered that human tumors display high levels of a specific highly sulfate type of CS normally restricted to placental and fetal tissue compartment. This "oncofetal" CS (ofCS) GAG can be conveniently detected and targeted using recombinant CS-binding VAR2CSA (rVAR2) lectins, derived from the malaria parasite Plasmodium falciparum. Recently, we identified chondroitin sulfate biosynthesis as being controlled by androgens in PC, modulating expression of the CHST11 and CHST13 carbon-4 GalNAc sulfotransferases. We established that these enzymes are under direct control of the androgen receptor (AR), regulating synthesis of the cancer-associated ofCS-modification on CSPGs. Glycosylation has a key role in many important biologic processes in cancer including cell differentiation. We identified CHST11 to be highly increased in high-risk neuroendocrine prostate cancer (NEPC) both in vitro, in vivo, and in situ. Moreover, cells that expressed neuroendocrine markers showed higher level of sulfation and ofCS. Our work reveals that alterations in GAG signatures regulated by AR might be responsible for progression neuroendocrine differentiation in prostate cancer. The prostate is an abundant secretor of PGs, and tumor-specific alterations in GAG signatures such as ofCS therefore constitute an untapped reservoir of potential biomarkers to be exploited as therapeutic targets.

Citation Format: Nader Al Nakouzi, Chris Kedong Wang, Irina Nelepcu, Coralie Crouzit, Noushin Nabavi, Amal Almami, Htoo Zarni Oo, Thomas Mandel Clausen, Tobias Gustavsson, Ali Salanti, Mads Daugaard. Expression and regulation of chondroitin sulfate in prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5229.
Abstract 5232: 1,25-Dihydroxyvitamin D3 mitigates lung cancer cell mediated mitochondrial dysfunction in human skeletal muscle
Authors: Ryan Zachary C. , Craig Theodore A. , Wang Xuewei , Delmotte Philippe , Salisbury Jeffrey L. , Lanza Ian R. , Sieck Gary C. , Kumar Rajiv
Published: August 2018

To assess cellular mechanisms that could contribute to muscle weakness in the context of cancer cachexia, we evaluated the effect of conditioned medium (CM) from highly tumorigenic Lewis lung carcinoma (LLC1) cells, CM from less tumorigenic MLE12 cells and non-CM on human skeletal muscle mitochondrial morphology and function. We assessed mitochondrial oxygen consumption, morphology, enzyme activity and gene expression in human skeletal muscle cells in the presence of tumor conditioned medium or control medium. We examined the secretome of LLC1 cells for mediators of skeletal muscle changes. We demonstrate that LLC1 CM inhibits cellular O2 consumption rate (OCR) and increases the proton production rate in human skeletal muscle cells. Mitochondrial fragmentation and the expression of the fission mediator, FIS1, are increased, whereas the expression of fusion mediators, OPA1 and MFN2 are reduced by LLC1 CM. LLC1 CM reduces pyruvate dehydrogenase (PDH) activity thereby limiting the production of acetyl CoA. Reduced PDH activity is associated with reduced PDHA1 sub-unit expression. The amount inactive phospho-PDH is increased in association with reduced PDP2 expression and increased PDK4 and SIRT4 expression in human skeletal muscle cells treated with LLC1 CM. The expression of several signaling pathways is altered by LLC1 CM in human skeletal muscle cells. When compared to MLE12 cells, LLC1 cells show increased expression of mRNAs encoding several potential mediators of altered muscle function such as Gdf15, TGFβ-induced protein, IL11, Il27, Il33, Il34, and PTH-like protein. We show that the active vitamin D metabolite, 1α,25(OH)2D3, that we previously demonstrated increases myoblast mitochondrial oxygen consumption and PDH activity, mitigates LLC1 CM effects on hSkMC OCR, mitochondrial fragmentation and mediators thereof. Mitochondrial oxygen consumption, morphology and enzyme activity in human skeletal muscle cells are inhibited or altered by tumor cell conditioned medium, and are reversed by 1α,25(OH)2D3, the active metabolite of vitamin D.

Citation Format: Zachary C. Ryan, Theodore A. Craig, Xuewei Wang, Philippe Delmotte, Jeffrey L. Salisbury, Ian R. Lanza, Gary C. Sieck, Rajiv Kumar. 1,25-Dihydroxyvitamin D3 mitigates lung cancer cell mediated mitochondrial dysfunction in human skeletal muscle [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5232.
Abstract 5239: Gli is a primary driver of prostate cancer cell growth
Authors: Li Na , Moore Jackson , Troung Sarah , Nouri Mannan , Foo Jane , Buttyan Ralph
Published: August 2018

Canonical Hedgehog signaling is a Smoothened- (Smo-) driven process that activates transcription from Gli proteins. However, we have shown that Hedgehog is activated in prostate cancer (PCa) cells by a non-canonical, non-Smo-dependent process mediated by the binding of transcriptionally active androgen receptors (AR) to the protein processing domain on Gli2/3. This binding competes with β-TrCP, and protects Gli3 (the predominant Gli isoform in PCa cells) from cleavage to its truncated repressor form (Gli3R). Our observations are consistent with the idea that AR transcriptional activity (mediated by liganded full-length AR or by truncated ARs) is effectively coupled to Gli activity in PCa. Here we present our evidence that Gli is the primary driver of PCa cell growth and that suppression of Gli transcriptional activity or interference with AR binding to Gli (using a decoy peptide) is a strong growth suppressor of androgen-dependent (AD) and -independent (AI) PCa cell lines. Gli transcription was inhibited by GANT61 or HPI-1 or by exogenous overexpression of a Gli3R cDNA. Each of these conditions significantly suppressed the growth of LNCaP parental (AD) and LNCaP-AI cells. Knockdown of Gli3 with siRNA decreased growth of a wide variety of PCa cell lines up to 75%. Finally, a decoy peptide (270aa) containing the Gli2 AR binding site displaced Gli3 from AR complexes, increased the levels of Gli3R and significantly suppressed growth of AI cell lines. Collectively, our data supports the idea that androgen-driven growth of PCa is a result of non-canonical activation of Gli and that interference with Gli binding to DNA or with the Gli-AR interaction is a means for suppressing PCa cell growth.

Citation Format: Na Li, Jackson Moore, Sarah Troung, Mannan Nouri, Jane Foo, Ralph Buttyan. Gli is a primary driver of prostate cancer cell growth [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5239.
Abstract 526: Mechanistic studies of TAp63 regulated oncogenic long noncoding RNAs in breast cancer metastasis
Authors: Li Xiaobo
Published: August 2018

Advanced breast cancer metastasis is the major cause of relapse. However, no effective treatment exists for the metastatic stage of breast cancer. Recently, regulatory long non-coding RNAs (lncRNAs) have been highlighted in p53 regulated genome protection in cancer metastasis; therefore approaches targeting lncRNAs is a promising strategy to treat breast cancer metastasis. Our laboratory aims to design such approaches through focusing on the p53 family member, TAp63 and its regulated lncRNAs. TAp63 has critical tumor suppressor function in breast cancer. Loss of function transforms mammary epithelial cells (MECs) into tumor initiating cells.

Our lab showed that loss of TAp63 in mouse MECs induces the expression of several lncRNAs. A locus conservation strategy was applied to identify the homologous lncRNAs relevant in human breast cancer progression. Targeting these lncRNAs with CRISPR/CAS9 system in human breast cancer cell line in mouse xenograft model demonstrated that they are required for the tumorigenic and metastatic potential of human breast cancer cells in vivo. The high-throughput protein microarray screening method was used to identify proteins that interact with these lncRNAs and facilitate their oncogenic functions. Importantly, the expression of both protein and lncRNA is negatively correlated with patient survival in breast cancer dataset, and positively correlated with breast cancer progression in human tissue microarrays.

We demonstrate the oncogenic effects of these lncRNAs in promoting breast cancer metastasis. Our data indicates that targeting lncRNAs directly or their effectors indirectly will provide innovative and effective therapeutics aiming the metastatic stage of breast cancer.

Citation Format: Xiaobo Li. Mechanistic studies of TAp63 regulated oncogenic long noncoding RNAs in breast cancer metastasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 526.
Abstract 5264: A prospective study of dietary inflammatory index scores and colorectal cancer risk: The Singapore Chinese Health Study
Authors: Luu Hung N. , Wang Renwei , Shivappa Nittin , Hébert James R. , Koh Woon-Puay , Yuan Jian-Min
Published: August 2018

Background. Colorectal cancer (CRC) has increased dramatically in Singapore during the past three decades and becomes the most common cancer when both sexes combined. Extensive evidence shown the specific component of diet may modulate inflammation and thus influence to disease endpoints, including CRC. We determine the association between diet inflammatory index (DII)TM, a literature-derived, population-based score, developed to assess the inflammatory potential of an individual's diet, and CRC risk in Singaporean Chinese, using data from the Singaporean Chinese Health Study (SCHS).

Methods. A total of 61,321 SCHS study participants was included in the current analysis. The DII scores were calculated using validated food frequency questionnaires (FFQs). Cox proportional hazards model was performed to assess the association between DII scores and CRC risk.

Results. There was a positive association between DII score and CRC risk in females (HRs and respective 95% CIs: 1.30 (1.02-1.64), 1.32 (1.03-1.67), and 1.20 (0.93-1.55) for Q2, Q3, Q4 vs. Q1). DII score was associated with increased risk of colon cancer (HRQ4vsQ1=1.35, 95% CI: 1.08-1.68; Ptrend=0.04) and this association appeared stronger in females. Among never-smokers, the highest quartile of DII was associated with statically significant 43% increased risk of developing CRC in women compared to those in the lowest quartile (HRQ4vsQ1=1.43, 95% CI: 1.01-2.02; Ptrend=0.03). There was also a dose-response association between DII scores with colon cancer in women among those with BMI less than 25 (HRQ4vsQ1=1.66, 95% CI: 1.03-2.68; Ptrend=0.04).

Conclusions. Consumption of anti-inflammatory foods will reduce the risk of colorectal cancer, particularly among females and non-smokers. This will have substantial public health impact as prevention program should focus on promoting healthy and anti-inflammatory foods to reduce the risk of colorectal cancer.

Citation Format: Hung N. Luu, Renwei Wang, Nittin Shivappa, James R. Hébert, Woon-Puay Koh, Jian-Min Yuan. A prospective study of dietary inflammatory index scores and colorectal cancer risk: The Singapore Chinese Health Study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5264.
Abstract 5288: MPNST treatment and diagnosis in NF1: A health economic model
Authors: Turkson Lydia , Mamuszka Hannah , Grimshaw Kyla , Marshall Erica Marie
Published: August 2018

Biomarkers have many applications along the care process in rare cancers and have potential to optimize treatment decisions. However, many diagnostic tests struggle to gain market access and appropriate value in terms of payer coverage because of a lack of evidence on their health economic benefit to patients. CMS reimbursement guidelines, of cost-plus pricing for diagnostics does not always work for niche small rare disease subpopulations. Nor does it reflect the lifelong value of effective patient care.

To address this, we have developed a cost benefit model for early diagnostic intervention, based on retrospective data to determine mutation status and monitor for disease progression in people diagnosed with neurofibromatosis type 1 (NF1) and soft tissue tumors. NF1 is an autosomal dominant hereditary cancer syndrome that affects around 1:2,500 people and is caused by mutations in the NF1 gene. 50% of patients can have few to many neurofibroma which vary in clinical behavior from benign to malignant. About 10% of people can develop malignant peripheral nerve sheath tumors (MPNSTs) thought to develop from pre-existing benign neurofibroma. Currently, there is no reliable way of knowing which individual and which tumors are malignant. MPNSTs are often difficult to diagnose in the early phases with current imaging methods like CT or MRI. Overall, these patients face a lifetime risk of cancer up to 16-26% higher than the normal population. Once metastasizes MPNSTs are associated with poor prognosis, less than 25% survival rate at 5 years.

We built a model used retrospective anonymized patient treatment records to demonstrate cost and risk based benefits to patients, payers and clinical practitioners, on the effect of early intervention versus late on treatment cost, and patient outcome in the long-term care process. For NF1 patients. In conclusion, our model proposes a new framework to engage healthcare insurers and managed care physician groups in the US to quantify the health economic benefits of prognostic biomarker tests in patient populations with a lifelong genetic predisposition to cancer.

Citation Format: Lydia Turkson, Hannah Mamuszka, Kyla Grimshaw, Erica Marie Marshall. MPNST treatment and diagnosis in NF1: A health economic model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5288.
Abstract 5290: My crown or my health: Black women's knowledge of breast cancer and hair product-related risk
Authors: Teteh Dede , Clark Phyllis , Dawkins-Moultin Lenna , Kittles Rick , Montgomery Susanne
Published: August 2018

Introduction/Purpose: Black women now have higher breast cancer (BC) incidence and mortality than White women. They also use more hair products containing hormonally-active chemicals. Studies are beginning to link chemical ingredients in these products to BC risk. Little is known about community knowledge of BC and the potential association with hair product-related risk. The purpose of this study was to evaluate the hazard level of hair products used by Black women, and assess their knowledge about BC and hair product-related risks.

Methodology: We employed principles of community-based participatory research and conducted the study through partnership between community advocates and university scientists. We collected hair products from locations frequented by Black women and hair stylists and used the Environmental Working Group's Skindeep© database to evaluate ingredient toxicity. We then explored knowledge of BC and hair product-related risk using a 41-item survey. Survey data were analyzed using SPSS.

Results: All 54 products evaluated contained hazardous ingredients. Fourteen of the ingredients had an overall high hazard rating between 7-10, with 10 indicating very high levels of toxicity. The potential harmful effects of these chemicals include cancer, endocrine disruption and reproductive system toxicant. Survey data showed most women (62%) in the sample had a college or graduate degree. Participants (n=211) were more knowledgeable about the diagnosis and treatment of BC (46.3%), lifestyle-related risk factors (59.6%), and genetic risk factors (54.9%) than about hair product risk (40.8%).

Conclusion: Several hair products frequently used by black women contained ingredients that have potential links to BC. Though the women in this study were highly educated, they had limited knowledge about the association between BC and toxins found in hair products. Research should further clarify the link between hair products and BC risk. As knowledge is evolving, given our emerging risk understanding, health educators and community advocates can promote efforts for women to learn more about exposure reduction to help them make informed decisions about the risk beauty product chemicals may hold regarding cancer. There is also a need for policies on personal care products that aim to protect the health of our communities.

Citation Format: Dede Teteh, Phyllis Clark, Lenna Dawkins-Moultin, Rick Kittles, Susanne Montgomery. My crown or my health: Black women's knowledge of breast cancer and hair product-related risk [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5290.
Abstract 5297: LCA: A robust and scalable algorithm to reveal subtle diversity in large-scale single-cell RNA-Seq data
Authors: Cheng Changde , Easton John , Rosencrance Celeste , Li Yan , Ju Bensheng , Chen Wenan , Chen Xiang
Published: August 2018

Single-cell RNA sequencing (scRNA-seq) emerges as a powerful tool to characterize cell-to-cell variation and dynamics in a seemingly homogenous population. Efficient and affordable, scRNA-seq is gaining in popularity in both basic and translational biological research areas. However, significant challenges arise in the analysis of scRNA-seq data, including low signal-to-noise ratio with high data sparsity, rising scalability hurdles with hundreds of thousands of cells, and more. Due to inherent complexities in scRNA-seq data, the performance of currently available algorithms may not always be optimal even for fundamental tasks such as identifying heterogeneous subpopulations in the data. In this study, we developed Latent Cellular Analysis (LCA), a machine learning based analytical pipeline that combines similarity measurement by latent cellular states with a graph-based clustering algorithm. LCA features a dual-space model search for both the optimal number of subpopulations and the informative cellular states distinguishing them. LCA provides heuristic solutions for population number inference, dimension reduction, feature selection and confounding factor removal without explicit gene filtering. LCA has proved to be robust, accurate and powerful by comparison to multiple state-of-the-art computational methods on large-scale real and simulated scRNA-seq data. Importantly, LCA's ability to learn from representative subsets of the data provides scalability, thereby addressing a significant challenge for growing sample size in scRNA-seq data analysis.

Citation Format: Changde Cheng, John Easton, Celeste Rosencrance, Yan Li, Bensheng Ju, Wenan Chen, Xiang Chen. LCA: A robust and scalable algorithm to reveal subtle diversity in large-scale single-cell RNA-Seq data [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5297.