tbuckley/cabot-search huggingface dataset:
Abstract 1834: Constitutive Nedd9 null genotype promotes lung cancer aggressiveness
Authors: Alexander Deneka, Meghan Kopp, Anna S. Nikonova, Anna Gaponova, Alexandra Nagele, Harvey Hensley, Erica Golemis
Journal: Cancer Research (2017)

Abstract Non-small cell lung cancer (NSCLC) has a low survival rate, with metastasis contributing to the vast majority of deaths. The NEDD9 (HEF1/Cas-L) protein has been reported to be elevated in expression and to promote metastasis in a large subset of lung cancers and in other malignancies. NEDD9 functions as a scaffold for multiple critical effectors in integrin/FAK/SRC and receptor tyrosine kinase signaling cascades, as well as for the mitotic kinase Aurora-A, with overexpression thought to sustain signaling by these pro-oncogenic proteins. Previous studies demonstrated depletion of NEDD9 by RNAi reduced the growth and invasion of established lung cell lines and tumors, based on cell culture and xenograft assays. We have now investigated the consequences of a null genotype for Nedd9 from the earliest stages of tumor formation, crossing Nedd9 null mice to a 129S/Sv-Krastm3Tyj/Trp53tm1Brn (KP) model in which Kras mutation is induced specifically in lung tissue by inhalation of adenovirus bearing the Cre gene. Unexpectedly, based on in vivo imaging, the Nedd9 null genotype significantly accelerated tumor growth in KP mice. Pathological examination of tissues indicated Nedd9 null genotype also was associated with higher invasive capacity in vivo, including direct invasion to the heart, as well as elevated proliferation rate, decreased apoptotic activity, and changes in the expression of proteins such as vimentin, associated with mesenchymal status. Although Nedd9 function has been implicated in immune cell activity, we found minimal differences in tumor infiltration of myeloid cells or macrophages based on Nedd9 genotype. Rather, use of Reverse Phase Protein Array (RPPA) analysis to characterize signaling in isolated tumors suggested tumor intrinsic changes in glycolytic and proliferative signaling pathways, which were subsequently validated using direct functional assays. These results for the first time imply that NSCLC tumor progression beyond early stages in the absence of Nedd9 requires reprogramming of intrinsic tumor signaling to compensate for the absence of this protein, emphasizing activities distinct from those associated with elevated Nedd9 in late stage tumors. Citation Format: Alexander Deneka, Meghan Kopp, Anna S. Nikonova, Anna Gaponova, Alexandra Nagele, Harvey Hensley, Erica Golemis. Constitutive Nedd9 null genotype promotes lung cancer aggressiveness [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1834. doi:10.1158/1538-7445.AM2017-1834
Abstract 3898: Emerging role of Fra-1 as a novel target for radiosensitization in HPV-associated cancers
Authors: Abhishek Tyagi, Shilpi Gupta, Prabhat Kuamr, Alok C. Bharti, Bhudev C. Das
Journal: Cancer Research (2017)

Abstract Background: Activator protein-1 (AP-1) plays a central role in HPV-mediated cervical and tongue cancer (subset of HNSCC). AP-1, a homo/heterodimeric protein composed of Jun and Fos family proteins, has been implicated in chemoradioresistance but the mechanism(s) remained unexplored. In the present study, AP-1 family protein Fra-1 has been shown to play a critical role in promoting radiosensitization in enriched cervical cancer stem-like cells (CaCxSLCs) and can serve as a target for drug intervention in cervical and other HPV associated cancers. Experimental Procedure: Cervical cancer stem-like cells (CaCxSLCs) were isolated and enriched by sequential gating HPV+ve and HPV-ve human cervical cancer cell lines, SiHa, and C33a using a set of functional and phenotypic markers (ABCG2, CD49f, CD71, CD133) in defined conditioned media (DCM) with intermittent culturing. CaCxSLCs were also assessed for their cervicosphere forming ability, exclusion of DCV dye for generating SP cells, self renewability and quiescenceness. Both CaCxSLCs and Non CaCxSLCs were exposed to different dose of UV irradiation and a herbal compound curcumin, a potent inhibitor of AP-1 was used to examine the role of AP-1 and its family proteins in the radiosensitization of cancer stem cells. Results: Upon UV irradiation, CaCxSLCs showed a dose-dependent higher proliferation and highly increased AP-1 activity whereas it was completely abolished in non-stem cancer cells. CaCxSLCs also showed differential overexpression of c-Fos and c-Jun at transcript as well as in protein level. The loss of AP-1 activity and expression was accompanied by decrease in cell viability and proliferation in UV irradiated non-stem cancer cells. Interestingly, CaCxSLCs treated with curcumin prior to UV irradiation abolished AP-1 activity and a concomitant reduction in SP cells leading to abrogation of sphere forming ability, loss of proliferation, induction of apoptosis and the cells were poorly tumorigenic. The curcumin pre-treatment abolished the expression of c-Fos and c-Jun but upregulated Fra-1 expression in irradiated CaCxSLCs. Conclusion: The study suggests a critical role of AP-1 protein in the manifestation of radioresistance but curcumin pretreatment helps in radiosensitizing CaCxSLCs through upregulation of Fra-1 which may serve as a potential target for elimination of radioresistant cancer stem cells in HPV-associated malignancies. Note: This abstract was not presented at the meeting. Citation Format: Abhishek Tyagi, Shilpi Gupta, Prabhat Kuamr, Alok C. Bharti, Bhudev C. Das. Emerging role of Fra-1 as a novel target for radiosensitization in HPV-associated cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3898. doi:10.1158/1538-7445.AM2017-3898
Abstract 82: MiR-206-mediated c-MET suppression modulates BCRP/ABCG2 levels inNRF2-silenced cancer cells
Authors: Bo-hyun Choi, In-geun Ryoo, Donghyeok Kim, Sujin Lee, Mi-Kyoung Kwak
Journal: Cancer Research (2017)

Abstract Breast cancer resistance protein (BCRP/ABCG2), a xenobiotic efflux transporter, is responsible for anticancer resistance in tumors. NF-E2-related factor 2 (NRF2) is a critical transcription factor in cellular defense system by regulating the expression of antioxidant and detoxifying enzymes; however, its overexpression is often associated with tumor resistance to chemotherapy. In the present study, we demonstrate that NRF2 modulation affects the expression of hepatocyte growth factor receptor (HGFR/c-MET) and consequently suppresses BCRP/ABCG2 activity in cancer cells. Interfering RNA-mediated stable inhibition of NRF2 in both ovarian carcinoma SKOV3 and renal carcinoma A498 cell lines reduced the expression of c-MET and this was accompanied by BCRP/ABCG2 down-regulation. The treatment of cells with pharmacological or genetic inhibitor of c-MET decreased BCRP/ABCG2 level and subsequently increased intracellular accumulation of doxorubicin and Hoechst 33342, indicating a link between c-MET and BCRP/ABCG2 activity. As a potential molecular mechanism of altered c-MET expression, miR-206 was identified as a predictive regulator of c-MET. As experimental evidence, transient and stable expressions of miR-206 in SKOV3 and A498 cells repressed c-MET and BCRP/ABCG2 levels. In addition, NRF2-knockdown cancer cells expressed higher levels of miR-206 compared to the control cells, and the treatment of NRF2 knockdown cells with the miR-206 inhibitor could restore c-MET and BCRP/ABCG levels. Collectively, our results showed that the NRF2 silencing-mediated miR-206 regulation could suppress BCRP/ABCG2 levels through c-MET modulation, which is providing an additional evidence of chemosensitization of tumor cells by NRF2 inhibition. Citation Format: Bo-hyun Choi, In-geun Ryoo, Donghyeok Kim, Sujin Lee, Mi-Kyoung Kwak. MiR-206-mediated c-MET suppression modulates BCRP/ABCG2 levels in NRF2-silenced cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 82. doi:10.1158/1538-7445.AM2017-82
Treatment of Hailey-Hailey Disease With Low-Dose Naltrexone
Authors: Lauren N. Albers, Jack L. Arbiser, Ron J. Feldman
Journal: JAMA Dermatology (2017)

Hailey-Hailey disease is a severe genetic blistering disease of intertriginous skin locations that can lead to poor quality of life and increased morbidities. Multiple therapies are available with inconsistent outcomes and potentially severe adverse effects.To determine whether low-dose naltrexone is an effective treatment for Hailey-Hailey disease.This study was a case series performed at a dermatology outpatient clinic of 3 patients with severe Hailey-Hailey disease recalcitrant to at least 4 therapies.Low-dose naltrexone, 3 mg nightly, titrated to 4.5 mg nightly in 2 patients.Reduction in size of lesions as well as subjective improvement of symptoms.All 3 patients noted significant healing of erosions and plaques starting from the peripheral aspect within 1 to 2 weeks of treatment, and clinical resolution of lesions within 2 months. Discontinuation of low-dose naltrexone resulted in flaring of symptoms, which cleared within 2 to 3 days on rechallenge with low-dose naltrexone.We present herein 3 cases of patients with severe Hailey-Hailey disease treated with low-dose naltrexone who achieved clinical resolution of symptoms. The success of these cases suggests low-dose naltrexone as a novel therapy for Hailey-Hailey disease. The possible mechanism may involve low-dose naltrexone influencing opioid or toll-like receptor signaling to improve calcium mobilization and improve keratinocyte differentiation and wound healing. Future studies are needed to clarify the mechanism and to define the role of low-dose naltrexone for treatment of Hailey-Hailey disease.
Abstract 4774: Polyamines are rich and induces epigenetic change by inhibition of LSD1 in cancer stem-like cells
Authors: Keisuke Tamari, Hideshi Ishii, Masamitsu Konno, Naohiro Nishida, Jun Koseki, Koichi Kawamoto, Fumiaki Isohashi, Yuichiro Doki, Masaki Mori, Kazuhiko Ogawa
Journal: Cancer Research (2017)

Abstract Cancer stem cells (CSC) are highly tumorigenic and resistant to chemotherapy and radiotherapy. We have previously reported that a small fraction of cancer cells with low proteasome activity had CSC-like properties. Ornithine decarboxylase (ODC) is an enzyme which converts ornithine to polyamines including putrescine, spermidine, and spermine. Proteasomal degradation of ODC is known to be ubiquitin-independent. The aim of this study was to explain how low proteasome activity gave CSC-like properties. Western blot showed high ODC protein level in CSC-like cells in cervical cancer and osteosarcoma cell lines, although ODC mRNA level is not high. These findings suggest that ODC protein level is high in CSC-like cells because ODC protein degradation is inactive. To investigate polyamine metabolism in CSC-like cells, we performed GC-MS analysis and found that putrescine, spermidine, and spermine were enriched in CSC-like cells. Furthermore, flux analysis showed conversion from ornithine to polyamines was more rapid in CSC-like cells. We performed a computational structure analysis and found that polyamines bind and inhibit demethylase site of LSD1 which is known to be a demethylase of histone H3K4 and a nuclear homolog of amine oxidases. Spermine was the strongest binding energy. An enzyme assay showed that LSD1 activity was dose-dependently inhibited by polyamines and spermine was the strong inhibitor. Finally, we analyzed performed ChIP sequencing analysis by using HeLa CSC-like cells and found that more global enrichment of H3K4me3 and less global enrichment of H3K4me1 than non-CSC-like cells. In conclusion, polyamines are rich in CSC, and be able to inhibit LSD1 activty and induce epigenetic alterations especially in H3K4 methylation in CSC. Citation Format: Keisuke Tamari, Hideshi Ishii, Masamitsu Konno, Naohiro Nishida, Jun Koseki, Koichi Kawamoto, Fumiaki Isohashi, Yuichiro Doki, Masaki Mori, Kazuhiko Ogawa. Polyamines are rich and induces epigenetic change by inhibition of LSD1 in cancer stem-like cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4774. doi:10.1158/1538-7445.AM2017-4774
Abstract 4839: Ephrin-A ligands regulate cutaneous tumor etiology and metastasis through cell autonomous and non-autonomous mechanisms
Authors: Ji Zheng, Bethany Perez White, Nihal Kaplan, Zhe Zhao, Miroslav Blumenberg, Spiro Getsios, Bingcheng Wang
Journal: Cancer Research (2017)

Abstract Glycophosphatidylinositol-anchored ephrin-A ligands target EphA receptor tyrosine kinases (RTKs) to promote keratinocyte differentiation. Accordingly, genetic ablation of the major epidermal EphA subtype, EphA2, increases susceptibility to DMBA/TPA-induced cutaneous chemical carcinogenesis. Defining the corresponding role of ligands for EphA2 in skin cancer has been more cumbersome as the three ephrin-A genes (Efna1, Efna3, Efna4) are all prominently expressed in skin. We met this challenge by utilizing a triple Efna1/3/4 knockout (TKO) mice that reflects the pattern of reduced Efna gene expression found in mouse and human cutaneous SCCs. Skin tumors developed earlier and grew faster in mice lacking EphA2 or these three ephrin-A ligands. Interestingly TKO mice displayed accelerated malignant progression toward invasive SCC that metastasized to the lymph nodes and lungs by 25 weeks following DMBA-TPA treatment. Using keratinocyte culture models, we found that ephrin-A ligands act within the epidermis to limit keratinocyte migration in a manner that depends on their targeting of EphA2. We also illustrated a key role for ephrin-A ligands in the surrounding tumor microenvironment by re-introducing isogenic SCC cell lines into the skin of wild-type or TKO mice on congenic FVB background; tumor growth and metastasis was facilitated in mice lacking ephrin-A ligands. Importantly, the invasive phenotype of TKO mouse tumor cell lines was normalized by genetic reintroduction of either Efna1 or Efna3. Integrating our findings from human tumors, mouse models, primary cell cultures, and allograft models provides strong support for the notion that ephrins operate within tumor cells and also in the microenvironment to suppress skin tumor initiation and metastasis. Note: This abstract was not presented at the meeting. Citation Format: Ji Zheng, Bethany Perez White, Nihal Kaplan, Zhe Zhao, Miroslav Blumenberg, Spiro Getsios, Bingcheng Wang. Ephrin-A ligands regulate cutaneous tumor etiology and metastasis through cell autonomous and non-autonomous mechanisms [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4839. doi:10.1158/1538-7445.AM2017-4839
Abstract 1281: Germline mutations in <i>NBN</i> conferring DNA damage response defects are found in patients with multiple cancer types
Authors: Sabine Topka, Michael F. Walsh, Ann Maria, Annie Lincoln, Diana Mandelker, Liying Zhang, Marc Ladanyi, Michael F. Berger, Mark E. Robson, Joseph Vijai, Kenneth Offit
Journal: Cancer Research (2017)

Abstract Nibrin, the protein encoded by the NBN gene forms a complex with Mre11 and Rad51 (MRN complex) that is crucial for DNA damage repair. Mutations in NBN are found in &amp;gt;90% of patients with Nimjegen breakage syndrome (NBS), an autosomal recessive disorder characterized by growth retardation, microcephaly, radiosensitivity, immunodeficiency and increased cancer risk. Most of NBS patients harbor the common founder mutation c.657del5 that leads to expression of a hypomorphic 70kDa C-terminal fragment produced by alternative translation initiation. Cell lines derived from these patients show increased sensitivity to DNA-damaging agents, chromosome instability, and abnormal cell cycle checkpoint function. Several studies have addressed cancer incidence in individuals with germline NBN mutations, showing increased cancer risk for individuals harboring the c.657del5 founder mutation and for carriers of the R215W missense mutation across multiple cancer types. For other NBN mutations conflicting reports exist as to their association with cancer risk. Here, we report newly identified NBN germline frameshift and truncating mutations in patients with multiple cancer types, including prostate, lung, breast cancer, acute lymphocytic leukemia, and chronic lymphocytic leukemia. Modeling these mutations in an NBN-deficient cellular background showed expression of a novel C-terminal truncated fragment that can bind to Mre11. Cells expressing these mutant proteins display attenuated DNA damage repair function and decreased overall survival following induction of DNA damage. Impaired Chk2 phosphorylation was also observed, indicating cell cycle checkpoint deficiencies. Thus, the NBN germline mutations identified here could contribute to genomic instability predisposing to tumorigenesis. Further in vitro studies with these and additional germline mutations occurring in cancer patients are ongoing, in order to better understand the role of this pathway of DNA damage repair in susceptibility to malignancies. Citation Format: Sabine Topka, Michael F. Walsh, Ann Maria, Annie Lincoln, Diana Mandelker, Liying Zhang, Marc Ladanyi, Michael F. Berger, Mark E. Robson, Joseph Vijai, Kenneth Offit. Germline mutations in NBN conferring DNA damage response defects are found in patients with multiple cancer types [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1281. doi:10.1158/1538-7445.AM2017-1281
Abstract 5398: High-throughput clonal analysis of AML tumors with droplet microfluidics
Authors: Dennis Eastburn, Maurizio Pellegrino, Sebastian Treusch, Adam Sciambi, Bill Hyun, Jamie Yates
Journal: Cancer Research (2017)

Abstract Single cell analysis tools are crucial to better understand the role that rare or heterogeneous cancer cells play in the evolution of tumor progression. Although, it is now feasible to perform single-cell RNA-Seq on thousands of, several challenges remain for high-throughput single-cell DNA sequencing. To address these challenges and enable the characterization of genetic diversity in cancer cell populations, we developed a novel approach that barcodes amplified genomic DNA of individual cells confined to microfluidic droplets. The barcodes are used to reassemble the genetic profiles of individual cells from next generation sequencing data. A key feature of our approach is the “two-step” microfluidic workflow that releases genomic DNA from cellular proteins prior to amplification. The microfluidic workflow first encapsulates individual cells in droplets, lyses the cells and prepares the lysate for genomic DNA amplification using proteases. Following this lysate preparation step, the proteases are inactivated and droplets containing the genomes of individual cells are then paired with molecular barcodes and PCR reagents. We demonstrate that the two-step microfluidic approach is vastly superior to workflows without the two-step process for efficient DNA amplification on tens of thousands of individual cells per run with high coverage uniformity and low allelic dropout of targeted genomic regions. To apply our single-cell sequencing technology to the study of acute myeloid leukemia (AML), we developed a targeted panel to sequence genes frequently mutated in AML including TP53, DNMT3A, FLT3, NPM1, NRAS, KRAS, JAK2, IDH1 and IDH2. Using this panel, we were able to identify clonal populations from AML research samples; moreover, the single-cell nature of our approach enabled the correlation of multiple mutations within subclones and determination of whether the mutations existed as as a homozygote or heterozygote. Collectively, our results show a greater degree of heterogeneity in AML tumor samples than is commonly appreciated with bulk sequencing methods. Citation Format: Dennis Eastburn, Maurizio Pellegrino, Sebastian Treusch, Adam Sciambi, Bill Hyun, Jamie Yates. High-throughput clonal analysis of AML tumors with droplet microfluidics [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5398. doi:10.1158/1538-7445.AM2017-5398
Abstract 3095: The development of CPI as a novel, next-generation DNA-targeting payload for ADCs
Authors: Jennifer Kahler, Maureen Dougher, Jane Xu, Matthew Doroski, Andreas Maderna, Russell Dushin, Stephane Thibault, Mauricio Leal, Madan Katragadda, Christopher J. O'Donnell, Matthew Sung, Puja Sapra
Journal: Cancer Research (2017)

Abstract DNA targeting drugs represent one of cornerstones of anti-cancer therapy for both hematologic and solid tumor indications. Low potency anti-DNA compounds (e.g. platins, anthracyclines) are included in many standard-of-care (SOC) regimens, however their modest activity and overall toxicity profiles limit their therapeutic potential. To increase the therapeutic window for DNA-damaging agents, high potency anti-DNA compounds with enhanced anti-tumor activity have been delivered to tumors as payloads of targeting modalities such as antibody-drug conjugates (ADCs). Herein, we describe the development of a novel DNA-damaging compound comprised of a dimeric structure of cyclopropylpyrrolo[e]indolones (CPIs) that was designed to alkylate DNA and generate toxic interstrand crosslinks (ICLs). In response to the CPI-induced formation of ICLs, CPI treatment of cells primarily activates the Fancomia anemia DNA damage response pathway, whereas other successful DNA-damaging ADC payloads such as calicheamicin activate double-strand break response pathways. CPI shows ~860-fold greater potency than calicheamicin in a panel of cell lines derived from a broad spectrum of tumor indications. Importantly, this new CPI payload retains potent activity in calicheamicin- and SOC-resistant tumor models (including overcoming overexpression of drug efflux pumps). When evaluated as payloads on anti-CD33 targeting ADCs, the CPI conjugate showed dramatically improved efficacy over the corresponding calicheamicin conjugates in MDR+ tumor models. As a site-specific conjugate, the CPI ADC shows enhanced in vivo stability and possesses a wider therapeutic window than the corresponding conventional calicheamicin conjugate and other leading DNA-damaging conjugates on the CD33 platform. Citation Format: Jennifer Kahler, Maureen Dougher, Jane Xu, Matthew Doroski, Andreas Maderna, Russell Dushin, Stephane Thibault, Mauricio Leal, Madan Katragadda, Christopher J. O'Donnell, Matthew Sung, Puja Sapra. The development of CPI as a novel, next-generation DNA-targeting payload for ADCs [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3095. doi:10.1158/1538-7445.AM2017-3095