bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 4406: Inducible knockdown of insulin receptor substrate I desensitizes ER alpha response to both agonist (estradiol) and antagonist (fulvestrant) in MCF-7L breast cancer cells
Authors: Zhang Xihong , Varma Sidhant , Yee Douglas 
Published: July 2016

Abstract
Insulin receptor substrate (IRS) proteins are adaptor proteins phosphorylated by insulin and insulin-like growth factor (IGF) receptors. In addition to their roles in regulating IGF and insulin responses, IRS proteins function in other pathways in normal and malignant physiology. Our data suggested that IRS1 enhanced IGF/insulin stimulated proliferation while IRS-2 was important in regulating motility. Therefore IRS proteins could be potential therapeutic target for cancer therapy. We have previously shown that reduced IRS1 can hinder cancer cell growth and tumorigenicity stimulated by IGF-I, IGF-II and insulin. In this study, we evaluated whether inducible IRS1 suppression affected estrogen receptor-alpha (ER) responsiveness to ER agonist estradiol and antagonist fulvestrant. We evaluated several doxycycline inducible shRNA IRS1 constructs (Thermo Scientific pTRIPZ inducible Lentiviral IRS1 shRNA) expressed in the ER+ MCF-7L cell line. Doxcycline treatment reduced IRS1 mRNA and protein levels confirmed by qRT-PCR and immunoblot in several independently selected clones. We used a representative clone (3G5) to evaluate effects on ER function. After IRS1 inducible knockdown, estradiol (E2) stimulated growth was suppressed. To investigate if reduced IRS1 regulated E2 stimulated binding of ER to the pS2 estrogen response element (ERE), chromatin immunoprecipitation (ChIP) assays were performed. Compared to non-induced MCF-7L cells, inducible IRS1 suppression demonstrated significantly reduced binding of ER to this promoter. The pharmacologic antagonist of IRS proteins, NT157, also resulted in diminished ER binding to pS2 promoter. mRNA of several ER regulated genes, such as PGR, TFF1, etc, showed downregulation in response to E2 when IRS-1 was suppressed. We have shown that the pure steroidal ER antagonist fulvestrant activates EGFR signaling in an ER dependent manner through upregulation of EGFR ligands. However, inducible IRS1 suppression blocked this ER-dependent activation of EGFR phosphorylation by fulvestrant yet EGFR phosphorylation remained intact when stimulated by addition of EGF. These data suggest that regulation of EGFR ligands by fulvestrant also requires IRS-1 expression. We conclude that ER function is affected by IRS-1 expression. Thus, IRS-1 may also be a target in endocrine responsive and resistant breast cancers.
Citation Format: Xihong Zhang, Sidhant Varma, Douglas Yee. Inducible knockdown of insulin receptor substrate I desensitizes ER alpha response to both agonist (estradiol) and antagonist (fulvestrant) in MCF-7L breast cancer cells. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4406.
Abstract 4410: ZEB2 drives cell motility and metastasis in ER+ breast cancer cells through a novel, E-cadherin independent pathway
Authors: Burks Hope E. , Rhodes Lyndsay V. , Martin Elizabeth C. , Hoang Van T. , Elliott Steven , Badoo Melody , Phamduy Theresa , Buechlein Aaron , Rusch Douglas , Chrisey Douglas , Flemington Erik , Nephew Kenneth , Collins-Burow Bridgette , Burow Matthew E. 
Published: July 2016

Abstract
Breast cancer is the most commonly diagnosed cancer in women, with the second highest mortality rate. The overwhelming majority of breast cancer deaths are a direct result of distant metastatic spread to vital organs such as lung, bone, and brain. The zinc finger transcription factor ZEB2 has been implicated as a driver of cancer cell motility, tissue invasion and metastasis in a number of diverse malignancies, but its role in breast cancer is not completely understood. We chose to examine the effects of direct overexpression of ZEB2 in the MCF-7 cell line, a luminal and estrogen receptor positive (ER+) derived breast cancer line. MCF-7-ZEB2 cells demonstrated significantly increased migration and invasion as well as an altered morphology in vitro compared to that of vector. Additionally, MCF-7-ZEB2 cells exhibited increased lung metastasis in vivo when implanted in an orthotopic xenograft mouse model. ZEB2 function in metastasis has canonically been attributed to transcriptional repression of the cell junction protein E-Cadherin. Here we establish that in ER+ breast cancer cells, ZEB2 fails to repress E-cadherin and promotes cell motility and metastasis through the induction of an E-cadherin independent signaling cascade. Next generation RNA sequencing analysis of the MCF-7-ZEB2 cells compared to vector revealed alteration of the MAPK signaling cascade, evidenced by enhanced expression of key motility and MAPK associated genes, including PLAU, EGF, ACTA2, and MMP9. Pharmacological inhibition of MAPK pathway completely abrogated ZEB2 induced migration, cell morphology changes and expression of target motility genes, confirming a necessary role for MAPK signaling in ZEB2-driven cell motility in ER+ breast cancer. Together these results indicate that the ZEB2 transcription factor drives motility in breast cancer cells through a novel MAPK dependent pathway, warranting further investigation into the mechanisms involved in ZEB2 action. Elucidating the pathways involved in ZEB2 function which are specific to ER+ breast cancer is an important step in understanding the processes underlying metastasis and has the potential to yield new therapeutic targets.
Citation Format: Hope E. Burks, Lyndsay V. Rhodes, Elizabeth C. Martin, Van T. Hoang, Steven Elliott, Melody Badoo, Theresa Phamduy, Aaron Buechlein, Douglas Rusch, Douglas Chrisey, Erik Flemington, Kenneth Nephew, Bridgette Collins-Burow, Matthew E. Burow. ZEB2 drives cell motility and metastasis in ER+ breast cancer cells through a novel, E-cadherin independent pathway. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4410.
Abstract 4412: c-Myc-driven lymphomas require calcium-modulating cyclophilin ligand (CAML) for survival and proliferation
Authors: Shing Jennifer C. , Lindquist Lonn D. , Bram Richard J. 
Published: July 2016

Abstract
Calcium-modulating cyclophilin ligand (CAML) is an endoplasmic reticulum (ER) protein that functions in a complex to mediate tail-anchored (TA) protein insertion into the ER membrane. CAML has also been implicated as a regulator of endocytic trafficking, modulator of intracellular calcium signaling, and essential factor for the survival and proliferation of specialized immune cells. To investigate the role of CAML in cell biology and cancer, we generated Eμ-Myc transgenic mice that carry a conditional deletion allele of CAML. From these mice, we derived B cell lymphoma cell lines driven by c-Myc and induced deletion of the CAML gene by treatment with tamoxifen to activate Cre-ERT2 in vitro. Homozygous loss of CAML in multiple independent B cell lymphoma lines activated apoptosis, while heterozygous deletion led to reduced cell proliferation. Apoptosis was inhibited by caspase inhibitor Q-VD-OPh or Bcl-2/xL overexpression; however, blocking apoptosis did not restore cell division. Loss of CAML did not activate the unfolded protein response, but did induce c-Jun and JNK phosphorylation. Structure-function studies indicated that lymphoma cell viability did not depend on interaction of CAML with TRC40, another component of TA protein insertion machinery. Conversely, expression of a minimal region of CAML that interacts with the TA insertion co-factor WRB was sufficient to rescue growth of CAML-deleted cells. In summary, our study demonstrates an essential pro-survival role for CAML in c-Myc-driven lymphomas. Future investigations will focus on the underlying mechanism of apoptosis in this system to advance our understanding of the biological functions of CAML, and consider CAML-dependent survival as a potential novel target for anticancer therapy.
Citation Format: Jennifer C. Shing, Lonn D. Lindquist, Richard J. Bram. c-Myc-driven lymphomas require calcium-modulating cyclophilin ligand (CAML) for survival and proliferation. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4412.
Abstract 4427: Role of Smurf2 in regulation of Smad anchor necessary for receptor activation (SARA) in TGFβ-receptor signaling
Authors: Lee Sanghyun , Di Guglielmo John M. 
Published: July 2016

Abstract
Non-small cell lung cancer (NSCLC) is a major form of lung cancer and is the leading cause of cancer mortality in the western world. Transforming growth factor β (TGFβ) deregulation leads to many human diseases: TGFβ is a tumor suppressor in normal lung epithelium; however, it switches roles and promotes lung cancer metastasis in cancer cells. TGFβ induces cell proliferation, migration and invasion in NSCLC cells.
The canonical pathway of TGFβ is initiated through binding of TGFβ ligand to transmembrane Ser/Thr kinase receptors, which propagate their signaling via receptor regulated R-Smads; proteins that function as intracellular effectors in the TGFβ pathway. Once activated, R-Smads form a complex with common (Co)-Smads that translocates into the nucleus to regulate transcriptional responses. Access of R-Smads to the activated receptor complex is regulated by an adaptor protein called Smad anchor for receptor activation (SARA). SARA facilitates the activation of Smads and allow efficient Smad signalling.
In addition to R-Smads and Co-Smads, inhibitory Smads (I-Smads) regulate TGFβ signalling. I-Smads block the signalling by competing against R-Smads for the association with TβR complex or by targeting receptors for ubiquitin-mediate degradation. I-Smads recruit the E3 ubiquitin ligases, Smad ubiquitination regulatory factors (Smurfs), to catalyze degradation of the receptor complex. The overall aim of the project is to characterize SARA in TGFβ receptor signalling and study the interaction of SARA with different proteins involved in the pathway, such as Smurf2 and Smad7.
We first examined how SARA, Smurf2 and Smad7 influence each other by performing a multi-combination transfection study. We also examined the interaction between SARA and Smurf2 through co-immunoprecipitation. We observed that the level of SARA decrease in the presence of Smurf2 and Smad7. In the presence of Smurf2 ligase inactive mutant and Smad7, the level of SARA is somewhat recovered. However, SARA does not directly interact with Smurf2. These data together suggest that SARA and Smurf2 influence each other in a very close manner. It also suggest that it could be a transient interaction. Characterizing SARA in TGFβ receptor signalling will provide us with possible drug targets for NSCLC.
Citation Format: Sanghyun Lee, John M. Di Guglielmo. Role of Smurf2 in regulation of Smad anchor necessary for receptor activation (SARA) in TGFβ-receptor signaling. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4427.
Abstract 4429: CCL20 regulation via TGFB /BMP signaling pathway in murine immortalized colonocytes and colonic epithelium
Authors: Brown Tasia D. , Means Anna , Freeman Tanner , Weaver Connie , Wilson Keith , Beauchamp. R. Daniel 
Published: July 2016

Abstract
TGFβ and BMP signaling through receptor-mediated activation of SMAD proteins is crucial for normal homeostasis in intestinal epithelium. Alterations in this pathway contribute to the development of colorectal cancers. To understand the role of these pathways in homeostasis of the colon we conditionally deleted loxP-flanked alleles of Smad4 in adult mouse colon. We used Lrig1CreERT allele to achieve greater than 80% SMAD4 gene deletion and a CK19CreERT allele for mosaic deletion in colonic epithelium. Our data indicates that SMAD4 activity regulates multiple interactions between intestinal epithelium cells and surrounding stroma and that deletion of SMAD4 in adult mouse colonic epithelial cells alters expression of cytokines, increases immune cell infiltration and predisposes mice to tumorigenesis. Increases in the chemokine CCL20 have been reported in CRC tumors beginning at the adenoma stage and it may regulate both Tregs and Th-17 cells in an active immune response. Luminex cytokine/chemokine array analysis revealed increased levels of CCL20 protein in colonic mucosa and RNAseq data revealed that when SMAD4 is knocked out in the epithelium there is an upregulation of CCL20 and CCR6 (receptor) mRNA in the epithelium and stroma, respectively. To further explore the regulation of CCL20, we used immortalized mouse colonocytes (IMC cells) to further determine how the TGFβ and BMP signaling pathways may be involved in CCL20 expression. We found that CCL20 mRNA expression was suppressed by TGFβ1 and BMP2 and increased by inhibitors of these pathways. The inhibition of CCL20 by the TGFβ and BMP2 pathways occurs even in the presence of a known strong inducer of CCL20, such as TNFα. We have further observed in mice induced to undergo deletion of SMAD4 in the intestinal epithelium that treatment with DSS results in 100% of mice developing mucinous adenocarcinomas in the distal colon. We conclude that ligand-dependent Smad4-mediated signaling provides important negative homeostatic regulation of CCL20 expression in colonic epithelium. Loss of Smad4 results in increased CCL20 expression and we are currently testing the hypothesis that CCL20 overexpression contributes to the inflammation induced carcinogenesis in this mouse model.
Citation Format: Tasia D. Brown, Anna Means, Tanner Freeman, Connie Weaver, Keith Wilson, R. Daniel Beauchamp. CCL20 regulation via TGFB /BMP signaling pathway in murine immortalized colonocytes and colonic epithelium. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4429.
Abstract 4431: Tandem profiling of 5-methyl and 5-hydroxymethylcytosine in glioblastoma identifies tumor-specific distribution of 5-hydroxymethylcytosine and associations with patient survival
Authors: Johnson Kevin C. , Houseman E. Andres , King Jessica E. , Fadul Camilo E. , Christensen Brock C. 
Published: July 2016

Abstract
Glioblastomas exhibit widespread molecular alterations including a highly distorted epigenome. Genome-wide assessment of epigenetic alterations to cytosines in glioblastoma has largely been limited to 5-methylcytosine (5mC). 5-hydroxymethylcytosine (5hmC) is an additional cytosine modification that is deregulated in cancer, though the extent and context of these alterations at single cytosine resolution remain unclear. Through parallel processing of DNA with bisulfite and oxidative bisulfite treatments on Illumina 450K arrays we resolved both 5mC and 5hmC in 30 glioblastomas. We developed and applied a novel technique for estimating 5mC, 5hmC, and unmethylated proportions from array data to glioblastoma tissues and compare with normal brain tissue. Genomic distribution of 5hmC was associated with features of transcription despite the glioblastoma genome being relatively depleted of 5hmC. When integrating 5mC and 5hmC data using a Gaussian finite mixture model approach, we observed significant associations between 5hmC levels and gene-sets involved in immune and RNA regulatory processes while high 5mC classes were associated with receptor-mediated processes and cancer gene-sets. Significant differences in patient survival were observed among classes of 5hmC obtained from a recursively partitioned mixture model. Gene expression across epigenetic enzymes including methyltransferases and TETs was also investigated for relation with patterns and levels of 5hmC and 5mC. Analyses of elevated 5hmC with alternative splicing events that may promote disease progression are underway. Together, our results provide a genome-wide map of 5hmC in glioblastoma, indicate that transcription patterns as well as disrupted processes are associated with 5hmC patterns, and highlight the potential clinical prognostic utility of 5hmC in cancer.
Citation Format: Kevin C. Johnson, E. Andres Houseman, Jessica E. King, Camilo E. Fadul, Brock C. Christensen. Tandem profiling of 5-methyl and 5-hydroxymethylcytosine in glioblastoma identifies tumor-specific distribution of 5-hydroxymethylcytosine and associations with patient survival. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4431.
Abstract 4443: Investigation of the promoter methylation status of the FHIT (fragile histidine triad) gene in larynx cancer
Authors: Demokan Semra , Akalin Kubra , Ozkoklesen Cansu , Ulusan Murat , Enver Necati , Dalay Nejat 
Published: July 2016

Abstract
Purpose: Development of carcinoma is associated with epigenetic modifications. Methylation of CpG islands in the promoter regions can participate in gene silencing and promote tumor aggressiveness. The Fragile histidine triad (FHIT) gene, localized on chromosome 3, is a tumor suppressor gene and the abnormal methylation of FHIT. The FHIT regulates the G2/M cell cycle check point and apoptotic pathwaysin various types of cancer. Inactivation of FHIT due to methylation has been shown in breast, cervical, gastric and colon carcinomas. In our study, we evaluated the FHIT gene promoter methylation in patients with larynx carcinoma (LC).
Experimental Design: Methylation of FHIT was investigated by bisulfite modification/methylation-specific polymerase chain reaction in tumors and matched normal tissue samples from 57 Turkish patients with LC.
Results: The promoter region of the FHIT was methylated in 96.49% and 29.82% of the primary tumors and the corresponding normal tissue samples, respectively [p = 0.0001, chi-square = 14.2105, OR(95%CI) = 64.7(14.4-296.07)]. A methylation rate (less than 10%) was observed in 3.51% (2/57) and 70.18% (40/57) of tumor and normal samples, respectively. Moderate methylation levels (10-25%) were found in 3.51% (2/57) of the tumors and 1.75% (1/57) of the adjacent normal tissues. High methylation levels (&gt;25%) were observed in 92.98% (53/57) and 28.07% (16/57) in the tumor and normal tissues, respectively.
Conclusion: Methylation may play an important role in LC carcinogenesis. Although we found that there was significant association between the methylation levels of tumor and adjacent normal tissues, high methylation levels of the FHIT was observed in the tumors when compared to the levels in normal tissue. These results suggest that the methylation rates of FHIT gene may provide a suitable biomarker in LC carcinogenesis. Our study is still in progress to include a larger cohort of patients.
Citation Format: Semra Demokan, Kubra Akalin, Cansu Ozkoklesen, Murat Ulusan, Necati Enver, Nejat Dalay. Investigation of the promoter methylation status of the FHIT (fragile histidine triad) gene in larynx cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4443.
Abstract 4444: DNA methylation age is accelerated in breast tissue of healthy women donors
Authors: Sehl Mary E. , Ganz Patricia A. , Horvath Steve 
Published: July 2016

Abstract
Background: Advanced age and cumulative estrogen exposure are well known risk factors for breast cancer. However, the mechanisms underlying the link between cellular senescence, chronic estrogen stimulation, increased cell cycling, and breast carcinogenesis are poorly understood. We examined epigenetic alterations that occur in the female breast with advancing age, and estrogen exposure.
Methods: We utilized specimens from 49 women healthy tissue donors from the Komen Tissue Bank who donated both breast tissue and peripheral blood at two time points spaced at least 2 years apart. Ages of the donors ranged from 18-65 years and they were grouped by menopausal status (27 pre- and and 22 post-menopausal) and parity (21 nulliparous). We assessed epigenome-wide DNA methylation levels (Illumina 450K platform) from DNA extracted from breast and blood tissue, and calculated tissue “DNA methylation age (DNAm age)” based on methylation levels at 353 CpGs that have been shown to strongly correlate with chronologic age across tissues. We examined the relationship between this outcome and age and variables related to cumulative estrogen exposure, including age at menarche, gravidity, parity, and menopausal status.
Results: DNAm age was highly correlated with chronological age in our sample (cor = 0.8, p&lt;0.001), within both peripheral blood (cor = 0.94, p&lt;0.001) and breast tissues (cor = 0.88, p&lt;0.001). When we examine the residuals for each sample from our regression analysis of DNAm age versus chronological age, we find that age acceleration is significantly increased in breast relative to peripheral blood tissue (p&lt;0.001). In a multivariate regression analysis, we found that earlier age at menarche (β = -0.62, p = 0.04) and higher gravidity (β = 0.95, p = 0.03) were associated with higher DNAm age.
Conclusions: We find that DNAm age is accelerated in breast tissue compared with peripheral blood cells in a population of healthy donors to the Komen Tissue Bank. We further note a significant association between DNAm age and early menarche, and rising number of pregnancies, suggesting that cumulative cell cycling with menstrual cycles and the tissue plasticity occurring with pregnancy may contribute to accelerated epigenetic age in the female breast.
Citation Format: Mary E. Sehl, Patricia A. Ganz, Steve Horvath. DNA methylation age is accelerated in breast tissue of healthy women donors. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4444.
Abstract 4456: Preliminary investigation of the promoter methylation status of BRCA1, BRCA2, TP53 genes of some breast cancer patients
Authors: Samuel Titilola A. , james babatunde ayo , HABEEB Muhammad , oshodi temitope , magbagbeola. olubunmi 
Published: July 2016

Abstract
Epigenetic alterations in BRCA1, BRCA2 and TP53, such as DNA methylation, may be an effective approach in diagnosis, prognosis and therapy in breast cancer. This study examines the DNA methylation signature of BRCA1, BRCA2 and TP53 in some breast cancer patients attending a Clinic in Lagos, Nigeria. In this study, 14 blood specimens with Invasive Ductal Carcinoma (IDC) were investigated. The samples were modified by Bisulfite modification, and then assessed by Methylation-Specific PCR (MSP). The methylation analysis indicates that 7(50%) of the 14 patients had a segment of the promoter region of BRCA1 gene methylated, 8 (57.14%) of BRCA2 methylated and 11(78.57%) of TP53 promoter region. This study provides preliminary evidence for the gene expression inactivation of BRCA 1, BRCA 2, and TP53 Genes in over 50% of the 14 patients with Stage 2 invasive ductal carcinoma who participated in this study.
Citation Format: Titilola A. Samuel, babatunde ayo james, Muhammad HABEEB, temitope oshodi, olubunmi magbagbeola. Preliminary investigation of the promoter methylation status of BRCA1, BRCA2, TP53 genes of some breast cancer patients. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4456.