bluuebunny/crossref_metadata_2025_split huggingface dataset:
Levels of Cyclooxygenase-2 Are Increased in the Oral Mucosa of Smokers: Evidence for the Role of Epidermal Growth Factor Receptor and Its Ligands
Authors: Moraitis Dimitrios , Du Baoheng , De Lorenzo Mariana S. , Boyle Jay O. , Weksler Babette B. , Cohen Erik G. , Carew John F. , Altorki Nasser K. , Kopelovich Levy , Subbaramaiah Kotha , Dannenberg Andrew J. 
Published: June 2022

Abstract
Cyclooxygenase-2 (COX-2) is a promising pharmacologic target for preventing aerodigestive malignancies. In this study, we investigated the effects of tobacco smoke on the expression of COX-2 in oral mucosa. An ~4-fold increase in amount of COX-2 mRNA was observed in the oral mucosa of active smokers versus never smokers. Thus, a series of in vitro studies were carried out to elucidate the mechanism by which tobacco smoke induced COX-2. Treatment of a nontumorigenic oral epithelial cell line (MSK-Leuk1) with a saline extract of tobacco smoke (TS) stimulated COX-2 transcription, resulting in increased amounts of COX-2 mRNA, COX-2 protein, and prostaglandin E2 (PGE2) synthesis. Exposure of cells to TS also caused an increase in epidermal growth factor receptor (EGFR) tyrosine kinase activity. Both an inhibitor of EGFR tyrosine kinase activity and a neutralizing anti-EGFR antibody blocked TS-mediated induction of COX-2. To define the mechanism by which TS activated EGFR, the release of amphiregulin and transforming growth factor α, two ligands of the EGFR, was measured. Exposure to TS caused a rapid increase in the release of both ligands. TS also markedly induced the expression of mRNAs for amphiregulin and transforming growth factor α. Importantly, increased expression of both ligands was also detected in the oral mucosa of active smokers. Taken together, these results suggest that activation of EGFR signaling contributes to the elevated levels of COX-2 found in the oral mucosa of smokers. Moreover, these findings strengthen the rationale for determining whether inhibitors of COX-2 or EGFR tyrosine kinase activity can reduce the risk of tobacco smoke–related malignancies of the aerodigestive tract.
N-Ras–Induced Growth Suppression of Myeloid Cells Is Mediated byIRF-1
Authors: Passioura Toby , Dolnikov Alla , Shen Sylvie , Symonds Geoff 
Published: June 2022

AbstractActivating mutations in ras oncogenes occur at high frequency in human malignancies and expression of activated ras in immortalized cells lines is generally transforming. However, somewhat paradoxically, ectopic expression of ras in some myeloid cell lines has been shown to induce growth suppression associated with up-regulation of the cyclin-dependent kinase inhibitor p21CIP1/WAF1 in a p16INK4a, p15INK4b, and p53 independent fashion. We have used cDNA array technology to compare the expression profile induced by activated N-ras (N-rasG13R) in growth-suppressed myeloid cells with that induced in myeloid cells, which are transformed by N-rasG13R. The expression profile induced in growth suppressed cells was consistent with differentiation and included the up-regulation of the transcription factor IFN regulatory factor-1 (IRF-1), a known transcriptional activator of p21CIP/WAF1 expression and a target of oncogenic mutations associated with myeloid leukemia. Antisense suppression of IRF-1 prevented N-rasG13R–associated growth arrest and up-regulation of p21CIP1/WAF1. These results define a novel tumor suppressive response to oncogenic signaling and provide a mechanistic link between growth suppression and differentiation in myeloid cells.
CASPASE-8 Gene Is Inactivated by Somatic Mutations in Gastric Carcinomas
Authors: Soung Young Hwa , Lee Jong Woo , Kim Su Young , Jang Jin , Park Yong Gyu , Park Won Sang , Nam Suk Woo , Lee Jung Young , Yoo Nam Jin , Lee Sug Hyung 
Published: June 2022

Abstract
Several lines of evidence indicate that deregulation of apoptosis is involved in the mechanisms of cancer development. Caspase-8 activation plays a central role in the initiation phase of apoptosis. The aim of this study was to explore the possibility that genetic alteration of CASPASE-8 gene is involved in the development of human cancers, including gastric cancers. We have analyzed the entire coding region of human CASPASE-8 gene for the detection of somatic mutations in 162 gastric carcinomas (40 early and 122 advanced cancers), 185 non–small cell lung cancers, 93 breast carcinomas, and 88 acute leukemias by PCR-single-strand conformation polymorphism. Of the cancers analyzed, 13 cancers harbored CASPASE-8 somatic mutations. Interestingly, all of the mutations were detected in the advanced gastric cancers (10.7% of the 122 samples). We expressed the tumor-derived caspase-8 mutants in 293T, 293, and HT1080 cells and found that most of the mutants (9 of the 10 mutations tested) markedly decreased the cell death activity of caspase-8. In addition, in the cells with the inactivating caspase-8 mutants, cleavage of poly(ADP-ribose)polymerase was markedly reduced compared with that of wild-type caspase-8. The occurrence of CASPASE-8 mutation and the inactivation of cell death activity by the mutants suggest that CASPASE-8 gene mutation may affect the pathogenesis of gastric cancers, especially at the late stage of gastric carcinogenesis.
Diminished Expression of C/EBPα in Skin Carcinomas Is Linked to Oncogenic Ras and Reexpression of C/EBPα in Carcinoma Cells Inhibits Proliferation
Authors: Shim Minsub , Powers Kristina L. , Ewing Sarah J. , Zhu Songyun , Smart Robert C. 
Published: June 2022

Abstract
The basic leucine zipper transcription factor, CCAAT/enhancer binding protein α (C/EBPα) is involved in mitotic growth arrest and has been implicated as a human tumor suppressor in acute myeloid leukemia. We have previously shown that C/EBPα is abundantly expressed in mouse epidermal keratinocytes. In the current study, the expression of C/EBPα was evaluated in seven mouse skin squamous cell carcinoma (SCC) cell lines that contain oncogenic Ha-Ras. C/EBPα mRNA and protein levels were greatly diminished in all seven SCC cell lines compared with normal primary keratinocytes, whereas C/EBPβ levels were not dramatically changed. Reexpression of C/EBPα in these SCC cell lines resulted in the inhibition in SCC cell proliferation. To determine whether the decrease in C/EBPα expression observed in the SCC cell lines also occurred in the carcinoma itself, immunohistochemical staining for C/EBPα in mouse skin SCCs was conducted. All 14 SCCs evaluated displayed negligible C/EBPα protein expression and normal C/EBPβ levels compared with the epidermis and all 14 carcinomas contained mutant Ras. To determine whether oncogenic Ras is involved in the down-regulation of C/EBPα, BALB/MK2 keratinocytes were infected with a retrovirus containing Ras12V, and C/EBPα protein, mRNA and DNA binding levels were determined. Keratinocytes infected with the retrovirus containing oncogenic Ras12V displayed greatly diminished C/EBPα protein, mRNA and DNA binding levels. In addition, BALB/MK2 cells containing endogenous mutant Ras displayed diminished C/EBPα expression and the ectopic expression of a dominant-negative RasN17 partially restored C/EBPα levels in these cells. These results indicate that oncogenic Ras negatively regulates C/EBPα expression and the loss of C/EBPα expression may contribute to the development of skin SCCs.
Testisin, a Glycosyl-Phosphatidylinositol–Linked Serine Protease, Promotes Malignant Transformation In vitro and In vivo
Authors: Tang Tenny , Kmet Muriel , Corral Laura , Vartanian Steffan , Tobler Andreas , Papkoff Jackie 
Published: June 2022

Abstract
Human testisin, a serine protease, is highly expressed in ovarian cancer and premeiotic spermatocytes with relatively little expression in other normal tissues. We first showed that testisin was localized on the surface of cultured tumor cells as a glycosyl-phosphatidylinositol–linked protein. We next explored the biological function of testisin in malignant transformation through manipulation of testisin expression in cell culture model systems. Small interfering RNA–mediated knockdown of endogenous testisin mRNA and protein expression in tumor cell lines led to increased apoptosis and diminished growth in soft agar. Conversely, overexpression of testisin in an epithelial cell line induced colony formation in soft agar as well as s.c. tumor growth in severe combined immunodeficient mice. A catalytic domain mutant was unable to induce soft-agar growth indicating that testisin protease activity is required for transformation. Ectopic expression of testisin in a human ovarian cancer cell line without endogenous testisin expression, led to the formation of larger tumors in severe combined immunodeficient mice. Data presented here provide the first demonstration that testisin can promote cellular processes that drive malignant transformation. Our functional data coupled with the restricted normal tissue distribution of testisin and its overexpression in a majority of ovarian cancers validates this cell surface protein as a target for therapeutic intervention.
Identification of OTX2 as a Medulloblastoma Oncogene Whose Product can be Targeted by All-Trans Retinoic Acid
Authors: Di Chunhui , Liao Shaoxi , Adamson David C. , Parrett Timothy J. , Broderick Daniel K. , Shi Qun , Lengauer Christoph , Cummins Jordan M. , Velculescu Victor E. , Fults Daniel W. , McLendon Roger E. , Bigner Darell D. , Yan Hai 
Published: June 2022

Abstract
Through digital karyotyping of permanent medulloblastoma cell lines, we found that the homeobox gene OTX2 was amplified more than 10-fold in three cell lines. Gene expression analyses showed that OTX2 transcripts were present at high levels in 14 of 15 (93%) medulloblastomas with anaplastic histopathologic features. Knockdown of OTX2 expression by siRNAs inhibited medulloblastoma cell growth in vitro, whereas pharmacologic doses of all-trans retinoic acid repressed OTX2 expression and induced apoptosis only in medulloblastoma cell lines that expressed OTX2. These observations suggest that OTX2 is essential for the pathogenesis of anaplastic medulloblastomas and that these tumors may be amenable to therapy with all-trans-retinoic acid.
Combined Haploinsufficiency for ATM and RAD9 as a Factor in Cell Transformation, Apoptosis, and DNA Lesion Repair Dynamics
Authors: Smilenov Lubomir B. , Lieberman Howard B. , Mitchell Stephen A. , Baker Ronald A. , Hopkins Kevin M. , Hall Eric J. 
Published: June 2022

Abstract
Loss of function of oncogenes, tumor suppressor genes and DNA damage processing genes has been implicated in the development of many types of cancer, but for the vast majority of cases, there is no link to specific germ line mutations. In the last several years, heterozygosity leading to haploinsufficiency for proteins involved in DNA repair pathways was shown to play a role in genomic instability and carcinogenesis after DNA damage is induced. Because the effect of haploinsufficiency for one protein is relatively small, we hypothesize that predisposition to cancer could be a result of the additive effect of heterozygosity for two or more genes, critical for pathways that control DNA damage signaling, repair or apoptosis. To address this issue, primary mouse cells, haploinsufficient for one or two proteins, ATM and RAD9, related to the cellular response to DNA damage were examined. The results show that cells having low levels of both ATM and RAD9 proteins are more sensitive to transformation by radiation, have different DNA double-strand break repair dynamics and are less apoptotic when compared with wild-type controls or those cells haploinsufficient for only one of these proteins. Our conclusions are that under stress conditions, the efficiency and capacity for DNA repair mediated by the ATM/RAD9 cell signaling network depend on the abundance of both proteins and that, in general, DNA repair network efficiencies are genotype-dependent and can vary within a specific range.
Targeting Tumor Angiogenesis with Adenovirus-Delivered Anti-Tie-2 Intrabody
Authors: Popkov Mikhail , Jendreyko Nina , McGavern Dorian B. , Rader Christoph , Barbas Carlos F. 
Published: June 2022

Abstract
Inhibition of tumor angiogenesis is a promising approach for cancer therapy. As an endothelial cell–specific receptor kinase expressed almost exclusively on the surface of vascular endothelium, Tie-2 has an important role in tumor angiogenesis. To explore the therapeutic potential of blocking Tie-2 receptor-interaction pathway, an adenoviral vector was used to deliver a recombinant single-chain antibody fragment rabbit intrabody (pAd-2S03) capable of inhibition of both mouse and human Tie-2 surface expression. pAd-2S03 was given to mice with well-established primary tumors, either a human Kaposi's sarcoma (SLK) or a human colon carcinoma (SW1222). The intrabody significantly inhibited growth of both tumors (75% and 63%, respectively) when compared with pAd-GFP control-treated tumors (P &lt; 0.01). Histopathologic analysis of cryosections taken from mice treated with pAd-2S03 revealed a marked decrease in vessel density, which was reduced by &gt;87% in both tumor models when compared with control-treated tumors (P &lt; 0.01). In contrast, human Tie-2-monospecific pAd-1S05 intrabody did not affect the growth of tumors, indicating that the antitumor effect of pAd-2S03 was due to the inhibition of tumor angiogenesis in these murine models. Our results show that the Tie-2 receptor pathway is essential for both SLK sarcoma and SW1222 colon carcinoma xenograft growth. The present study shows the potential utility of antiangiogenic agents that target the endothelium-specific receptor Tie-2 for down-regulation or genetic deletion.
Abstract 6284: Exosomal miR-29b derived from mesenchymal stem cell (MSC) may suppress peritoneal metastasis via the effects on peritoneal mesothelial cells
Authors: Kimura Yuki , Ohzawa Hideyuki , Kaneko Yuki , Tamura Kohei , Futoh Yurie , Takahashi Kazuya , Saito Akira , Tojo Mineyuki , Miyato Hideyo , Kitayama Joji 
Published: June 2022

Abstract
Background: Mesothelial cells play tumor-promoting roles in the development of peritoneal metastasis (PM) through mesothelial-mesenchymal transition (MMT). We reported miR-29b suppressed MMT of human peritoneal mesothelial cell (HPMC).
Methods: MiR-29b mimics and negative control miRNA (NC) were transfected to human bone marrow derived MSC by lipofection method. Exosomes were purified from the culture supernatants of the MSC with ultracentrifugation, and added to HPMC. Proliferation and migration of HPMC were examined with MTT assay and transwell assay, respectively. MMT of HPMC induced by 10 ng/ml TGF-β, and evaluated with immunofluorescence staining.
Results: MSC transfected with miR-29b mimics produced significantly increased amounts of miR-29b-containing exosomes (p&lt;0.0001, n=3) as compared with negative control. After 24h-culture with PKH-26 stained exosomes, HPMC actively took the exosomes. After 48 hr-culture with TGF-β, HPMC apparently changed the morphology from round to spindle shape. The expression level of E-cadherin and Calretinin in HPMC was decreased while vimentin and Fibronectin tended to be upregulated by TGF-β. However, exosomes from miR-29b transfected MSC significantly suppressed the morphological changes and reduced the expression levels of vimentin and Fibronectin with restored expression of E-cadherin and Calretinin, suggesting the inhibition of MMT in HPMC. The exosome inhibited the proliferation and migration of HPMC by 31±14% (p&lt;0.01, n=5) and 67±9% (p&lt;0.01, n=3), and inhibited the adhesion of NUGC by 90±3% (p&lt;0.001, n=5) as compared with NC exosome.
Conclusion: Exosomes from MSC transfected with miR-29b mimic efficiently suppresses MMT. Replacement of the miR-29b in peritoneal cavity might be used for the treatment of PM partially via the effects on mesothelial cell.
Citation Format: Yuki Kimura, Hideyuki Ohzawa, Yuki Kaneko, Kohei Tamura, Yurie Futoh, Kazuya Takahashi, Akira Saito, Mineyuki Tojo, Hideyo Miyato, Joji Kitayama. Exosomal miR-29b derived from mesenchymal stem cell (MSC) may suppress peritoneal metastasis via the effects on peritoneal mesothelial cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 6284.
Abstract 629: Benefit of using a spectral flow analyzer for the analysis of immune cell populations in tumors
Authors: Metzger Philipp , Malaisé Muriel , Obodozie Cynthia , Weber Holger 
Published: June 2022

Abstract
Flow cytometry is a widely applied approach for exploratory immune profiling and enables the identification of individual cells in a cell population, such as a tumor cell suspension, by staining cell markers with antibodies conjugated with a fluorophore. The markers allow for the differentiation of a large variety of immune cell populations, their change in frequency, and activation status upon treatment. Conventional flow cytometers, which use bandpass filters and need conventional compensation matrices, are limited by the number of parameters that can be simultaneously analyzed, restricting their utility. Spectral analysis technology promises a greater flexibility for panel design, a higher number of analyzed parameters, and more accurate visualization of results.
Our standard all-in-one flow cytometry panel uses all possible fluorescent detectors of the flow analyzer BD Fortessa, which permits the differentiation of the main immune cell populations in the tumor, such as T cells (CD4+, CD8+, Treg), B and NK cells, macrophages (M1/M2), MDSCs (granulocytic and monocytic), and dendritic cells. However, in addition to immune cell frequency, it would also be interesting to investigate cell surface activation and memory markers like PD-1, CD40, CD44, or CD62L or intracellular activation markers like IFN-gamma, perforin, granzyme B, or Ki67. The 32-channel spectral flow analyzer SP6800 ZE from Sony allows the combination of both.
Flow cytometry data of different tumor samples will be presented, as well as the comparison of the results and resolution of both flow analyzer systems. Auto-fluorescence of cells, which causes fluorescent signal contamination of other fluorescent markers in the conventional flow cytometer, can be subtracted using spectral technology to see the true fluorescent population, thereby allowing dim signal detection in rare populations. A comprehensive overview will be given regarding the pros and cons of the spectral analyzer system and difficulties switching from the one system to the other.
Citation Format: Philipp Metzger, Muriel Malaisé, Cynthia Obodozie, Holger Weber. Benefit of using a spectral flow analyzer for the analysis of immune cell populations in tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 629.
Transcriptional Plasticity Drives Leukemia Immune Escape
Authors: Eagle Kenneth , Harada Taku , Kalfon Jérémie , Perez Monika W. , Heshmati Yaser , Ewers Jazmin , Koren Jošt Vrabič , Dempster Joshua M. , Kugener Guillaume , Paralkar Vikram R. , Lin Charles Y. , Dharia Neekesh V. , Stegmaier Kimberly , Orkin Stuart H. , Pimkin Maxim 
Published: June 2022

Abstract

Relapse of acute myeloid leukemia (AML) after allogeneic bone marrow transplantation has been linked to immune evasion due to reduced expression of major histocompatibility complex class II (MHCII) genes through unknown mechanisms. In this work, we developed CORENODE, a computational algorithm for genome-wide transcription network decomposition that identified a transcription factor (TF) tetrad consisting of IRF8, MYB, MEF2C, and MEIS1, regulating MHCII expression in AML cells. We show that reduced MHCII expression at relapse is transcriptionally driven by combinatorial changes in the expression of these TFs, where MYB and IRF8 play major opposing roles, acting independently of the IFNγ/CIITA pathway. Beyond the MHCII genes, MYB and IRF8 antagonistically regulate a broad genetic program responsible for cytokine signaling and T-cell stimulation that displays reduced expression at relapse. A small number of cells with altered TF abundance and silenced MHCII expression are present at the time of initial leukemia diagnosis, likely contributing to eventual relapse.

Significance:
Our findings point to an adaptive transcriptional mechanism of AML evolution after allogeneic transplantation whereby combinatorial fluctuations of TF expression under immune pressure result in the selection of cells with a silenced T-cell stimulation program.
This article is highlighted in the In This Issue feature, p. 369
Identification of a Distinct Platelet Phenotype in the Elderly: ADP Hypersensitivity Coexists With Platelet PAR (Protease-Activated Receptor)-1 and PAR-4–Mediated Thrombin Resistance
Authors: Gnanenthiran Sonali R. , Pennings Gabrielle J. , Reddel Caroline J. , Campbell Heather , Kockx Maaike , Hamilton Justin R. , Chen Vivien M. , Kritharides Leonard 
Published: June 2022

Background:

Thrombin (via PAR [protease-activated receptor]-1 and PAR-4) and ADP (via P2Y
12
receptors) are potent endogenous platelet activators implicated in the development of cardiovascular disease. We aimed to assess whether platelet pathways alter with aging.

Methods:
We characterized platelet activity in community-dwelling volunteers (n=174) in the following age groups: (1) 20 to 30 (young); (2) 40 to 55 (middle-aged); (3) ≥70 years (elderly). Platelet activity was assessed by aggregometry; flow cytometry (surface markers [P-selectin: alpha granule release, CD63: dense granule release, PAC-1: measure of conformationally active GPIIb/IIIa at the fibrinogen binding site]) measured under basal conditions and after agonist stimulation [ADP, thrombin, PAR-1 agonist or PAR-4 agonist]); receptor cleavage and quantification; fluorometry; calcium flux; ELISA.

Results:

The elderly had higher basal platelet activation than the young, evidenced by increased expression of P-selectin, CD63, and PAC-1, which correlated with increasing inflammation (IL [interleukin]-1β/IL-6). The elderly demonstrated higher P2Y
12
receptor density, with greater ADP-induced platelet aggregation (
P
<0.05). However, elderly subjects were resistant to thrombin, achieving less activation in response to thrombin (higher EC
50
) and to selective stimulation of both PAR-1 and PAR-4, with higher basal PAR-1/PAR-4 cleavage and less inducible PAR-1/PAR-4 cleavage (all
P
<0.05). Thrombin resistance was attributable to a combination of reduced thrombin orienting receptor GPIbα (glycoprotein Ibα), reduced secondary ADP contribution to thrombin-mediated activation, and blunted calcium flux. D-Dimer, a marker of in situ thrombin generation, correlated with platelet activation in the circulation, ex vivo thrombin resistance, and circulating inflammatory mediators (TNF [tumor necrosis factor]-α/IL-6).

Conclusions:
Aging is associated with a distinctive platelet phenotype of increased basal activation, ADP hyperreactivity, and thrombin resistance. In situ thrombin generation associated with systemic inflammation may be novel target to prevent cardiovascular disease in the elderly.