bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 1739: Diminished SKP1 or CUL1 expression induces chromosome instability in high-grade serous ovarian cancer precursor cells
Authors: Lepage Chloe C. , Nachtigal Mark W. , McManus Kirk J. 
Published: August 2019

Abstract
High-grade serous ovarian cancer (HGSOC) is the most common ovarian cancer subtype as well as the most lethal. High mortality rates associated with HGSOC are in part due to a lack of reliable early detection methods and effective therapies. Importantly, chromosome instability (CIN; an increased rate of chromosome gains or losses), is causally implicated in cancer development, progression, and resistance to treatment, and is just beginning to be evaluated in an HGSOC context. Overexpression of Cyclin E1 protein induces CIN and genomic amplification contributes to HGSOC pathogenesis in 20% of HGSOC patients. Cyclin E1 protein levels are normally regulated in a cell cycle-dependent manner by the SCF (SKP1-CUL1-FBOX) complex, an E3 ubiquitin ligase that targets substrates for proteolytic degradation. In cases where genomic amplification is absent, we hypothesize that loss of SCF complex function stemming from diminished expression of individual SCF complex components underlies increases in Cyclin E1 levels and induces CIN. The current study focuses on the SCF complex components SKP1 and CUL1 and characterizes their role in early HGSOC pathogenesis within a fallopian tube secretory epithelial cell model (FT; a cell of origin for HGSOC). Using siRNA-based approaches, we show that diminished SKP1 and CUL1 expression results in increased Cyclin E1 protein levels in FT cells. Using quantitative imaging microscopy techniques, we further identify statistically significant changes in CIN-associated phenotypes within the silenced populations, including changes in nuclear areas, increases in micronucleus formation (i.e. small DNA-containing bodies outside of the primary nucleus), and increases in numerical chromosome abnormalities identified in mitotic chromosome spreads. Thus, the current study explores the early origins of HGSOC and identifies SKP1 and CUL1 as two promising new molecular players that may contribute to CIN to drive FT cell transformation, drug resistance and disease recurrence.
Citation Format: Chloe C. Lepage, Mark W. Nachtigal, Kirk J. McManus. Diminished SKP1 or CUL1 expression induces chromosome instability in high-grade serous ovarian cancer precursor cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1739.
Abstract 1741: Identification of microsatellite instability in hematologic malignant cell lines
Authors: Bhattacharya Priyanjali , Chikan Naveed Anjum , Sharma Arati , Desai Dhimant , Annageldiyev Charyguly , Patel Pinaki , Patel Trupti N. 
Published: August 2019

Abstract
Defective DNA repair machinery which is a consequence of chromosomal or molecular alterations is associated with variety of diseases including solid tumors. Cytogenetic analysis is an important tool in diagnosis and treatment of hematologic malignancies. Our aim is to understand the role of microsatellite instability in initiation and progression of blood cancers. Here we hypothesize that leukemogenic cells may carry defective repair mechanisms that contribute to other genomic instabilities. In order to explore the possible role of microsatellite instability (MSI) in leukemia and lymphoma, eight different DNA repair genes involved in mismatch repair (MMR) and direct reversal of damage (DRD) were analyzed in K562 (CML), Molt-4 (T-ALL) and Daudi (Burkitt’s lymphoma) cell lines. Fragment analysis was carried out using novel primers considering repeat motifs enriched with (A)n, (CA)n and (AT)n for instability. Almost all the cell lines showed moderate to high level of microsatellite instability and exhibited a shift in selected repeat regions indicating possible loss (66.7%) (MSH2, MSH4, MSH6, MLH1, MLH3, PMS1) or gain (25%) (MSH3, MGMT) of nucleotide repeats as compared to normal DNA. The K562, Philadelphia negative CML cell line appeared to be microsatellite stable (MSS) for genes MSH2 and MLH1. Treatment induced microsatellite instability is known in leukemic patient cells as also seen in Molt-4 cells. Our present and previous observations suggest that MSI is a non-random event in leukemia/lymphoma which needs confirmatory future studies in newly diagnosed untreated patient samples. Considering the fact that both MSI and MSS represents two distinct molecular pathways of carcinogenesis, assessment of MSI, if added as distinct diagnostic criteria, can possibly refine early detection and help in identifying novel targets in management of hematologic malignancies.
Citation Format: Priyanjali Bhattacharya, Naveed Anjum Chikan, Arati Sharma, Dhimant Desai, Charyguly Annageldiyev, Pinaki Patel, Trupti N. Patel. Identification of microsatellite instability in hematologic malignant cell lines [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1741.
Abstract 1754: Monoubiquitinated γ-H2AX - a more specific biomarker of DNA double-strand breaks
Authors: Luczak Michal W. , Zhitkovich Anatoly 
Published: August 2019

Abstract
DNA double-strand brakes (DSBs) are a highly toxic form of DNA damage originating from many endogenous and exogenous sources. Cells employ specialized mechanisms for rapid detection and repair of these lesions. Histone H2AX phosphorylated at Ser139 (known as γ-H2AX) acts as a central platform for recruitment of other components of DSB repair. γ-H2AX assessment is currently the most widely used approach for quantitation of DSBs. However, γ-H2AX can be also induced by certain nongenotoxic stressors and during apoptosis, which can lead to false positive observations, especially in prolonged exposures. γ-H2AX undergoes RNF168-mediated K13/K15 monoubiquitination which is necessary for the recruitment of the downstream DSB repair factors. This ubiquitination event is rarely analyzed despite its functional importance. We examined formation and detection of γ-H2AX and its mono- (ub1) and diubiquitinated (ub2) forms in several human cell lines in response to mechanistically distinct inducers of DSBs and false-positive DSBs stressors. We found that γ-H2AX-ub forms were poorly detected using some common blotting procedures and antibodies. Under optimized conditions, γ-H2AX-ub1 was the predominant form accounting up to 80-90% of total γ-H2AX in primary human cells and its formation was strictly associated with the presence of DSBs. γ-H2AX and γ-H2AX-ub1 showed similar dose dependence and disappearance kinetics whereas H2AX-ub2 form was a more stable and dose-independent product. Unlike γ-H2AX, its ubiquitinated forms were not observed in the absence of DSBs (heat-shock or during apoptotic DNA cleavage). Apoptotic cells showed cleavage of the γ-H2AX-targeting E3 ubiquitin ligase RNF168. Our findings demonstrate that the ub1 form is a major fraction in the overall formation of γ-H2AX and its quantitation offers advantage in specificity for nonapoptotic DSBs.
Citation Format: Michal W. Luczak, Anatoly Zhitkovich. Monoubiquitinated γ-H2AX - a more specific biomarker of DNA double-strand breaks [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1754.
Abstract 1771: Role of Tsc2-mTORC1 signaling in homeostasis of intestinal epithelium and its relation to inflammation and cancer
Authors: Kotani Takenori , Setiawan Jajar , Murata Yoji , Saito Yasuyuki , Matozaki Takashi 
Published: August 2019

Abstract
Intestinal tumorigenesis driven by mutations in adenomatous polyposis coli gene requires the mammalian target of rapamycin complex 1 (mTORC1) activity, whereas the physiological roles of mTORC1 in the homeostasis of intestinal epithelial cells (IECs) remain virtually unknown. We here generated mice, in which tuberous sclerosis complex 2 (Tsc2), a negative regulator of mTORC1, was specifically ablated in IECs (Tsc2 CKO mice). Tsc2 CKO mice manifested the enhanced proliferative activity of IECs in intestinal crypts as well as the promoted migration of these cells along the crypt-villus axis. In vitro study showed that conditional ablation of Tsc2 in IECs promoted development of intestinal organoids, while mTORC1 inhibitor, rapamycin, diminished this phenotype. Tsc2 CKO mice also manifested the increased apoptotic rate of IECs as well as the increased ectopic Paneth cells, which are one of the major differentiated IECs. In addition, such conditional ablation of Tsc2 resulted in a suppressed expression of Wnt target genes in the colonic epithelium. Finally, we found that Tsc2 CKO mice manifested the increased susceptibility for dextran sulfate sodium (DSS)-induced colitis. Although mTORC1 and Wnt signaling pathways are thought to cooperated to promote oncogenesis in the intestinal epithelium, our results thus suggest that the mTORC1 signaling unexpectedly counter-regulates the Wnt signaling with the maintenance of intestinal homeostasis.
Citation Format: Takenori Kotani, Jajar Setiawan, Yoji Murata, Yasuyuki Saito, Takashi Matozaki. Role of Tsc2-mTORC1 signaling in homeostasis of intestinal epithelium and its relation to inflammation and cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1771.
Abstract 1778: 5’-nucleotidases are involved in the biology of human lung cancer cell lines
Authors: Raza Muhammad Zawwad , Cadassou Octavia , Cros-Perrial Emeline , Puisieux Alain , Dumontet Charles , Jordheim Lars Petter 
Published: August 2019

Abstract
Cytosolic-5’-nucleotidase II (cN-II) and ecto-5′-nucleotidase (CD73) are enzymes involved in the nucleotide metabolism by dephosphorylating intracellular and extracellular purine nucleotide monophosphates, respectively. Both enzymes have been shown to be involved in cancer by modifying anticancer drug activity, cancer cell biology and immune modulation. To increase the knowledge of cN-II and CD73 roles in cancer cell biology, we developed lung cancer cell models (NCI-H292) with a complete knockout of either or both enzymes using the CRISPR-Cas9 technique. These cell models are used to study cell proliferation and migration, cancer drug sensitivity, cellular behaviour and apoptosis using CFSE staining, IncuCyte relative confluence and wound healing assay, MTT assay, xCELLigence RTCA and caspase-3/7 apoptotic assay. SCID CB17 mice are also used to study the in vivo tumor growth using these cell models. Our results show that there is no significant difference in proliferation between different cell models exposed or not to different concentrations of either adenosine or AMP under normoxic and hypoxic conditions. On the other hand, using xCELLigence RTCA technique, we have observed that CD73-deficient cells have higher cell index as compared to CD73 expressing cells under basal conditions during the first 72 hours of culture. However, adenosine globally decreases the cell index of all NCI-H292 cells, unlike AMP, which influences the cell index of cN-II-deficient cells but not CD73-deficient cells. Under hypoxic condition, cN-II-deficient cells showed higher cell index than the other phenotypes in untreated conditions, whereas cells lacking CD73 showed higher sensitivity to adenosine or AMP. As compared to other phenotypes, CD73 deficient cells are also more sensitive towards vincristine but less sensitive towards mitomycin and fludarabine. These cells are also more prone to adapt to hypoxic conditions and exhibit slower migration rate than their corresponding control cells. However, the effect of adenosine and AMP on migration rate is higher on cN-II-deficient cells. Mice experiments showed no difference in in vivo tumor growth using these cell models. Overall, we show that both CD73 and cN-II are important players in the cell biology of lung cancer cells and in their response to purines. Upcoming experiments should help us understand the molecular mechanisms underlying these observed differences.
Citation Format: Muhammad Zawwad Raza, Octavia Cadassou, Emeline Cros-Perrial, Alain Puisieux, Charles Dumontet, Lars Petter Jordheim. 5’-nucleotidases are involved in the biology of human lung cancer cell lines [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1778.
Abstract 1781: Transcriptional activation of CBFβ by CDK11p110 is necessary to promote osteosarcoma cell proliferation
Authors: Feng Yong , Hornicek Francis , Duan Zhenfeng 
Published: August 2019

Abstract
Aberrant expression and activation of cyclin-dependent protein kinase (CDK) is a hallmark of cancer. CDK11 is a protein kinase in the CDK family and plays a crucial role in cancer cell growth and proliferation. However, the molecular mechanisms of CDK11 in osteosarcoma and CDK11 transcriptional regulated genes are largely unknown. In this study, we performed global transcriptional analysis using gene array technology to investigate the transcriptional role of CDK11 in osteosarcoma. The promoter luciferase assay, chromatin immunoprecipitation assay, and Gel Shift assay were used to identify direct transcriptional target of CDK11. Clinical significance relevance and function of CBFβ were further accessed in osteosarcoma tissue microarray and in osteosarcoma cell lines. We identified a transcriptional role of protein-DNA interaction for CDK11p110, but not CDK11p58, in the regulation of core-binding factor subunit beta (CBFβ) expression in osteosarcoma cells. The CBFβ promoter luciferase assay, chromatin immunoprecipitation assay, and Gel Shift assay confirmed that CBFβ is a direct transcriptional target of CDK11. High expression of CBFβ is associated with poor outcome in osteosarcoma patients. Expression of CBFβ contributes to the proliferation and metastatic behavior of osteosarcoma cells. These data establish CBFβas a mediator of CDK11p110dependent oncogenesis and suggest that targeting the CDK11-CBFβ pathway may be a promising therapeutic strategy for osteosarcoma treatment.
Citation Format: Yong Feng, Francis Hornicek, Zhenfeng Duan. Transcriptional activation of CBFβ by CDK11p110 is necessary to promote osteosarcoma cell proliferation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1781.
Abstract 1787: Selective activation of a PI3K catalytic isoform by G protein-coupled receptors in glioblastoma
Authors: Winn Abigail R. , Sheng Zhi 
Published: August 2019

Abstract
Objective: To determine how PI3K catalytic isoforms become dysregulated in glioblastoma.
Background: Recurrence in glioblastoma (GBM) is common and even more resistant to treatment than initial GBM. The Sheng Lab has previously identified that PIK3CB expression levels, but not other PI3K subtypes, are higher in recurrent GBM and are associated with GBM recurrence in newly diagnosed individuals. PI3KCB encodes for PI3K catalytic subunit p110β, and PI3K/AKT pathway activation is a well-known promoter of cell survival. Understanding mechanisms of PIK3CB activation in GBM may identify new therapeutic targets and improve GBM survival. Current knowledge of PI3K isoform activity in GBM is insufficient and contradictory. Given previous studies, it was hypothesized that G-Coupled Protein Receptor (GPCR) promoters preferentially activate PI3K/AKT in PIK3CBhigh GBM cells. Further, that knockdown of PIK3CB, but not other PI3K isoforms, inhibits PI3K/AKT reactivation in PIK3CBhigh cell lines.
Design/Methods: U87MG cells, an established p110βhigh GBM cell line, were starved overnight in serum free media, and then treated with growth factors, promoters or inhibitors of several previously hypothesized pathways. Cell lysates were collected and PI3K/AKT pathway activity was measured with immunoblotting. The ratio of pAKT/AKT/ACTB quantified PI3K/AKT pathway activity.
Results: Overnight serum starvation depleted pAKT, and incubation with 1% FBS restored pAKT signaling in a time dependent manner. Neither EGF nor FGF-2 activated PI3K/AKT signaling. Gefitinib, an EGFR inhibitor, failed to inhibit reactivation when cells were co-treated with 1% FBS. However, GPCR stimulation by Lysophosphatidic acid (LPA) increased pAKT/AKT ratios in a dose dependent manner. More significantly, Gallein, a GPCR inhibitor, suppressed PI3K/AKT signaling when cells were co-treated with 1% FBS. Selective PI3K inhibitors showed little PI3K/AKT reactivation at multiple doses.
Conclusions: These results suggest that GPCR signaling is responsible for PI3K/AKT pathway activation in p110βhigh cells.
Citation Format: Abigail R. Winn, Zhi Sheng. Selective activation of a PI3K catalytic isoform by G protein-coupled receptors in glioblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1787.
Abstract 1789: The importance of the phosphatase PRL family sub-cellular localization during the cellular cycle
Authors: O'Leary Anna K. , Blackburn Jessica 
Published: August 2019

Abstract
Acute lymphoblastic leukemia (ALL) is one of the most prevalent cancers diagnosed in adolescents. The survival rate for ALL is good during the initial diagnosis but is much less optimistic for patients who have relapsed ALL, due to limited treatment options. Additionally, the high dose cytotoxic chemotherapies given to ALL patients have long term adverse consequences. New and less toxic targeted therapies are needed for the treatment of ALL. We previously performed a large scale transplantation screen in zebrafish to identify genes associated with high relapse potential in ALL, and a top hit from this screen was the protein tyrosine phosphatase 4A3, PTP4A3 or PRL3. PRL3 overexpression in zebrafish enhances ALL progression and penetrance, and small molecule targeting of PRL3 in human cells rapidly induces apoptosis. The mechanisms through which PRL3 drive ALL progression and survival are unknown. PRL3 has a predicted nuclear localization site as well as a predicted prenylation motif, causing its localization to the plasma membrane. My preliminary data suggest that PRL3 shifts its localization between the plasma membrane and nucleus during the cell cycle. I am currently examining the localization of PRL3 and other PRL family members during different phases of the cell cycle and identifying signaling pathways that they may be involved with at these distinct sites to promote ALL progression, using CLIP-tag and SNAP-tag technologies that will allow me to image directly PRL localization in vitro. Biotin ligase approaches (Turbo-ID) will be used to determine the substrates of PRL activity and PRL interacting partners at these distinct locations. My project will provide scientific data that supports our hypothesis that PRL3 can transition between the membrane and nucleus, and plays a role in cell cycle. Identification of substrates of PRL3 that promote ALL progression may provide novel drug targets for this disease.
Citation Format: Anna K. O'Leary, Jessica Blackburn. The importance of the phosphatase PRL family sub-cellular localization during the cellular cycle [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1789.
Abstract 179: M6A demethylation enzyme FTO upregulates LDHA and promotes glycolysis and invasion and migration in oral squamous cell carcinoma
Authors: Hou Jinsong 
Published: August 2019

Abstract
Objective: To investigate the role of lactate dehydrogenase A (LDHA) in the glycolysis and invasion and metastasis of oral squamous cell carcinoma (OSCC), and to explore the molecular mechanism of fat mass and obesity-associated protein (FTO) regulating LDHA on the glycolysis and invasion and metastasis of OSCC.
Methods: Immunohistochemistry and RT-qPCR were performed to detect the expression of LDHA protein and gene in OSCC and adjacent non-cancerous tissues, and their correlation with clinical prognosis and pathological parameters were analyzed. Lentivirus-mediated shRNA silencing of LDHA and lactate dehydrogenase inhibitor (oxamate) were used to establish stable OSCC Cell lines HSC3 and SCC15, Cell Counting Kit-8 and colony formation assay were applied to evaluate cell proliferation, scratch test and Transwell assay were performed to detect cell migration and invasion, Glucose utilization assay and Lactate production assay were carried out to assess cell uptake of glucose and lactate production respectively. The molecular mechanism of FTO regulating LDHA on glycolysis, invasion and metastasis of oral squamous cell carcinoma was further explored, OSCC cell lines HSC3 and SCC15 transfected with siRNAs to silence FTO expression, EpiQuik™ m6A RNA Methylation Quantification Kit was applied to assess the m6A% in total RNA, the effect of FTO on LDHA expression was detected by Western blot and RT-qPCR. The biological function of FTO on oral squamous cell carcinoma cells was demonstrated by cell experiments in vitro.
Results: Compared with adjacent non-cancerous tissues, LDHA was highly expressed in OSCC (P&lt;0.001), which was closely related to the differentiation, clinical stage and T stage of OSCC (P&lt;0.05). Silencing LDHA, FTO or treating oxamate in HSC3 and SCC15 cells reduced glucose consumption, lactate production and cell proliferation, invasion and migration (P&lt;0.05). In addition, after FTO silencing, the m6A level of total RNA increased (P&lt;0.05), while the expression level of LDHA protein and mRNA decreased (P&lt;0.01).
Conclusion: FTO may promote the expression of LDHA protein and mRNA in a m6A-dependent manner and enhance the ability of glycolysis, proliferation, invasion and
metastasis of OSCC.
Note: This abstract was not presented at the meeting.
Citation Format: Jinsong Hou. M6A demethylation enzyme FTO upregulates LDHA and promotes glycolysis and invasion and migration in oral squamous cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 179.