bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 2904: The alternative NF-kB2/RELB pathway is activated by LTB/LTB receptor and NIK to promote cell migration and metastasis-related gene expression in HNSCC
Authors: Das Rita , Cheng Tsu-Fan , Coupar Jamie , Saleh Anthony , Clavijo Paul E. , Yang Xinping , Chen Zhong , VanWaes. Carter 
Published: July 2016

Abstract
Head and neck squamous cell carcinomas (HNSCC) are highly inflammatory and preferentially migrate and metastasize to lymph nodes. In this study, we find that LTβ/LTβR/NIK signaling mediates alternative RELB/NF-kB2 activation, which promotes activation of important cancer related genes and migration. We find that LTβ and LTβR are over expressed in subsets of HNSCC tissues and cell lines, and LTβ activates the alternative NF-κB pathway, enhancing nuclear translocation of RELB and NF-kB2/p52. Knockdown of LTβR decreased its target kinase NIK, and downstream NF-kB subunits RELB and NF-kB2/p52 protein expression. Knockdown of NIK protein decreased RELB and p52 protein expression, while LTβ treatment stabilized NIK, RELB and NF-kB2/p52 expression. Consistent with this, knockdown of LTBR and NIK functionally decreased NF-kB reporter gene activity, while treatment of LTB partially restored the NF-kB reporter activity. Notably, knockdown of NIK and RELB by siRNA inhibited cell migration in HNSCC. Since NIK is known as central regulator of the activation of the non-canonical pathway, we tested the effects of a NIK inhibitor 1,3[2H,4H]-Isoquinolinedione on NF-kB function and cell migration. NIK inhibitor decreased NIK protein in the cytoplasm, downstream nuclear expression of RELB and NF-kB2/p52 proteins by Western blot and RELB localization by immunofluorescence staining. We have found evidence for LTβ induction of migration/metastasis and cell death genes MET, BIRC3,and SERPINE1, and NIK knockdown inhibited cell migration and the inducible expression of MET, BIRC3, SERPINE 1 by LTB. Our data reveal the mechanisms how LTβ and NIK activation mediated alternative NF-kB pathway and contribute to migration and metastasis of HNSCC.
Supported by NIDCD intramural Project ZIA-DC-000016, 73 and 74.
Citation Format: Rita Das, Tsu-Fan Cheng, Jamie Coupar, Anthony Saleh, Paul E. Clavijo, Xinping Yang, Zhong Chen, Carter VanWaes. The alternative NF-kB2/RELB pathway is activated by LTB/LTB receptor and NIK to promote cell migration and metastasis-related gene expression in HNSCC. [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 2904.
Abstract 2914: Biphenylene and bipyridine connected benzofuran compounds as novel regulators of kRAS transcription
Authors: Batra Harshul , Islam Mohammad K. , Thurston David E. , Rahman Khondaker M. , Brooks Tracy A. 
Published: July 2016

Abstract
Pancreatic cancer is the fourth most deadly cancer with 5 year survival rate of ∼6%. One of the major attributes of pancreatic cancer is kRAS mutations. kRAS is a proto-oncogene with intrinsic GTPase activity, and is responsible for cell proliferation, division, and apoptosis. kRAS mutations are observed in &gt;95% of pancreatic adenocarcinoma and in 30% all human tumors. When mutated it leads to continuous activity and uncontrolled proliferation which results in increased tumorigenicity and poor prognosis. Downregulating kRAS expression has shown to halt proliferation and leads to cellular death in pancreatic cancer models, but to date no small molecule capable of such transcriptional silencing has been described. A novel series of molecules with either biphenylene or bipyridine spacer connecting the terminal benzofuran ring was synthesized using solution phase chemistry. Tertiary amine side chains were incorporated to the C2-position of the benzofuran ring to improve the DNA binding affinity of these compounds. The synthesized compounds were purified using a “catch and release” method employing the sulfonic acid based resins. The eleven novel compounds were screened in parallel for their ability to stabilize G-quadruplex structures in the kRAS promoter, and to downregulate kRAS promoter activity. Two of the compounds increased the thermal profile of non-canonical DNA formations in the promoter region by &gt;5 °C; however, on the whole these compounds did not seem to function as G-quadruplex-stabilizing agents. Eight compounds significantly decreased luciferase expression under the explicit control of the kRAS promoter by up to 75%, by compound BF 4.3, through an as-yet unknown mechanism of action. The compound series was examined for the inhibition of cellular viability in two mutant kRAS pancreatic cancer cell lines - Panc-1 and MIA PaCa-2; in both cell lines the compounds containing the bipyridine spacer had greater cytotoxic effects with IC50's of ∼30 μM, consistently. qPCR is being used to confirm the decrease in promoter activity in native cellular conditions. These agents are intriguing in both their novel scaffold and their unexpected activity decreasing kRAS expression in a mechanism unrelated to higher order DNA structures. Ultimately, down regulation of kRAS transcription will provide a novel therapeutic approach for pancreatic cancer and improve the prognosis of this highly lethal disease.
Citation Format: Harshul Batra, Mohammad K. Islam, David E. Thurston, Khondaker M. Rahman, Tracy A. Brooks. Biphenylene and bipyridine connected benzofuran compounds as novel regulators of kRAS transcription. [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 2914.
Abstract 2915: Penfluridol suppresses glioblastoma tumor growth by inhibiting sonic hedgehog signaling
Authors: Ranjan Alok , Srivastava Sanjay K. 
Published: July 2016

Abstract
Glioblastoma (GBM) is the most common brain tumor with poor survival rate. The main obstacle in the treatment of glioblastoma patients is the presence of blood brain barrier, which restricts the movement of the drugs to reach the brain. Penfluridol (PF) is known to cross blood brain barrier and is a clinically approved drug for schizophrenia patients. It is demonstrated and established by us that penfluridol suppresses the growth of metastasized breast cancer cells in brain giving us the rationale to evaluate it against glioblastoma (Alok Ranjan, Parul Gupta and Sanjay Srivastava, Cancer Research 2015). Penfluridol significantly reduced the viability of U87-MG, T98G and U251 MG glioblastoma cells with an IC50 of 6μM, 5.5μM and 9μM respectively after 24 h of treatment and induced apoptosis as exhibited by FITC/Annexin assay and cleavage of caspase 3 as well as PARP. It has been shown that GLI1, a transcription factor belonging to sonic hedgehog signaling is overexpressed in GBM and responsible for tumor progression. Our results demonstrated that penfluridol treatment reduced the expression of GLI1 in U87MG, T98G and U251 MG cells in concentration-dependent manner. In addition, overexpression of MGMT, a DNA repair enzyme has been linked to temozolomide (TMZ) resistance in GBM therapy. Combination of PF and TMZ induced more apoptosis and reduced the expression of GLI1 and MGMT as compared to PF or TMZ treatment alone. Our results further demonstrated that oral administration of PF inhibited the growth of GBM tumors by 66% and 72% in subcutaneous and intracranial GBM tumor model respectively. Immunohistochemical analysis of tumor tissue and western blot analysis of tumor lysate indicated down regulation of GLI1, MGMT and increase in cleavage of caspase 3, confirming in vitro finding. Apoptosis induction effect of PF treatment in tumor tissues was further confirmed by Tunel staining. Taken together, these results indicate that overall GBM tumor growth suppression by penfluridol was associated with inhibition of Gli1 and induction of apoptosis
Citation Format: Alok Ranjan, Sanjay K. Srivastava. Penfluridol suppresses glioblastoma tumor growth by inhibiting sonic hedgehog 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 2915.
Abstract 2917: Therapeutic targeting of the mitochondria: An evaluation of the transcriptional link between the antioxidant response and autophagy
Authors: Pokrzywinski Kaytee L. , Mascia Francesca , Rao. V. Ashutosh 
Published: July 2016

Abstract
Mitoquinone (MitoQ), a mitochondrially targeted chemotherapy induces autophagy via excess reactive oxygen species (ROS) production. Elevations in ROS stimulate nuclear factor (erythroid-derived 2)-like 2 (Nrf2) in breast cancer cell lines. Nrf2 is a nuclear transcription factor that activates the antioxidant response element when under oxidative stress. The aim of this study was to evaluate transcriptional and protein changes associated with Nrf2 activation to identify potential links between oxidative stress, autophagy and cell death. By suppressing Nrf2 and its targeted antioxidant enzymes we should induce elevated ROS levels, which can thereby alter cellular homeostasis and impact the ultimate fate of cancer cells. In the breast cancer cell line MDA-MB-231 RNA was extracted after 24 hours of Nrf2 or non-target pool (NTP) silencing and 18 hours of MitoQ treatment. RNA was sequenced using an Illumina HiSeq and differential expression was analyzed using DESeq in the statistical program R. To avoid bias, raw read counts were filtered to remove low counts possibly due to constraints of the instrumentation. To validate efficient silencing of Nrf2 we confirmed that Nrf2 transcript levels decreased and that there were observed reductions in transcripts containing the Nrf2 transcriptional promoter, the antioxidant response element (ARE) including FTH1, FTL, HMOX1, SRXN1, TXNRD1, NQO1, GCLC, GCLM, GSR and SQSTM1. From there we validated RNAseq data with qPCR using 25 random transcripts and found significant positive correlation between the two methods. Comparisons were first made between the MitoQ and DMSO treatment by silencing (NTP or Nrf2). 2775 genes were differentially expressed (DE) for MitoQ vs DMSO NTP siRNA and 1869 genes were DE for MitoQ vs DMSO Nrf2 siRNA both at an α &lt; 0.05 and Log2 fold change cut off &gt; |1|. We then compared the degree of overlap in DE gene lists between the NTP and Nrf2 siRNA comparisons to identify genes affected only by Nrf2 silencing in combination with MitoQ treatment. 1405 mRNAs were common between silenced and non-silenced sample sets, only 464 mRNAs were due to Nrf2 silencing alone. We are currently performing pathway analysis on these transcripts to determine the role of Nrf2 silencing with redox-active therapies. We are also evaluating autophagic protein levels at later time points, 24 to 48 hours, to further evaluate the potential signaling between oxidative stress and the autophagic response driven by Nrf2.
Citation Format: Kaytee L. Pokrzywinski, Francesca Mascia, V. Ashutosh Rao. Therapeutic targeting of the mitochondria: An evaluation of the transcriptional link between the antioxidant response and autophagy. [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 2917.
Abstract 2931: Integrated genomic approaches identify upregulation of SCRN1 as a novel mechanism associated with acquired resistance to erlotinib in non small cell lung cancer cells with oncogenic EGFR mutation
Authors: Kim Nayoung , Cho Ahye , Watanabe Hideo , Choi Yoon-La , Aziz Meraj , Kassner Michelle , Joung Je-Gun , Park Angela KJ , Francis Joshua , Bae Joon Seol , Ahn Soo-min , Kim Kyoung-Mee , Park Joon-Oh , Park Woong-Yang , Ahn Myung-Ju , Park Keunchil , Yin Hongwei Holly , Cho Jeonghee 
Published: July 2016

Abstract
Therapies targeting the tyrosine kinase activity of Epidermal Growth Factor Receptor (EGFR) have been proven to be effective in treating a subset of non-small cell lung cancer (NSCLC) patients harboring activating EGFR mutations. Inevitably these patients develop resistance to the EGFR-targeted tyrosine kinase inhibitors (TKIs). Here, we performed integrated genomic analyses using an in vitro system to uncover alternative genomic alterations responsible for acquired resistance to EGFR-TKIs. Specifically, we identified 80 genes whose expression is significantly increased in the resistant clones and RNAi-based systematic synthetic lethal screening revealed that suppression of one upregulated transcript, SCRN1, a secernin family member, restores sensitivity to erlotinib by enhancing inhibition of PI3K/AKT signaling pathway. Furthermore, we detected increased levels of SCRN1 in 5 of 11 lung tumor specimens from EGFR-TKIs refractory patients by immunohistochemistry. Taken together, we propose that upregulation of SCRN1 is an additional mechanism associated with acquired resistance to EGFR-TKIs in a subset of lung cancer patients and that its suppression serves as a novel therapeutic strategy to overcome drug resistance in these patients.
Citation Format: Nayoung Kim, Ahye Cho, Hideo Watanabe, Yoon-La Choi, Meraj Aziz, Michelle Kassner, Je-Gun Joung, Angela KJ Park, Joshua Francis, Joon Seol Bae, Soo-min Ahn, Kyoung-Mee Kim, Joon-Oh Park, Woong-Yang Park, Myung-Ju Ahn, Keunchil Park, Hongwei Holly Yin, Jeonghee Cho. Integrated genomic approaches identify upregulation of SCRN1 as a novel mechanism associated with acquired resistance to erlotinib in non small cell lung cancer cells with oncogenic EGFR mutation. [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 2931.
Abstract 2933: Long-term BRAF(V600E) inhibition results in a spontaneous KRAS(G12D) mutation and increased epithelial to mesenchymal transition (EMT) in papillary thyroid cancer cells (PTC)
Authors: Danysh Brian P. , Cabanillas Maria E. , Hofmann Marie-Claude 
Published: July 2016

Abstract
Objective:
Activating mutations in BRAF(V600E) are commonly observed in PTC and result in a functional dependence upon the constitutively active MAPK pathway. While targeted inhibitors are initially effective, inevitably cells develop alternative mechanisms of pathway activation. Mechanisms of primary resistance have been described in thyroid cancer cell lines, however acquired resistance has not. Our study investigates adaptive mechanisms of BRAF(V600E) inhibitor resistance and accompanying metastatic phenotypes in PTC cells following long-term vemurafenib exposure.
Materials & Methods:
KTC1 sub-cell lines (PTC cells, BRAFV600E) were developed following treatment with either 0.25 or 1.0 μM of vemurafenib, a BRAF V600E inhibitor, for &gt;20 passages. Western blot and qRT-PCR were used to assess EMT marker expression and pathway activation. 2D and 3D invasion assays, immunofluorescence microscopy, and direct cell count growth assays were used to assess inhibitor resistance and metastatic phenotypes. Sequenom was used to detect acquired mutations.
Results:
A vemurafenib resistant (VR) subline of KTC1 cells was derived following long-term treatment with the drug. Resistance coincided with spontaneous acquisition of a KRAS(G12D) activating mutation. Our data show KRAS(G12D) driven vemurafenib-resistance significantly enhanced expression of distinct EMT markers and translated into increased growth, migration, and invasion, when compared to the control sub-lines. This gain in metastatic phenotype coincided with increase activation of both the AKT and ERK pathways.
Conclusion:
Our results suggest an acquired KRAS mutation confers BRAF V600E inhibitor resistance and a more aggressive metastatic phenotype in vitro. Our hope is that further study of the mechanisms of resistance will add to potential markers for early detection of BRAF inhibitor resistance, leading to improved patient outcomes.
Citation Format: Brian P. Danysh, Maria E. Cabanillas, Marie-Claude Hofmann. Long-term BRAF(V600E) inhibition results in a spontaneous KRAS(G12D) mutation and increased epithelial to mesenchymal transition (EMT) in papillary thyroid cancer cells (PTC). [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 2933.
Abstract 2935: Systematic drug testing and RNA-sequencing of tamoxifen resistant breast cancer cell lines
Authors: Hultsch Susanne , Kangaspeska Sara , Kankainen Matti , Pietiäinen Vilja , Kallioniemi Olli 
Published: July 2016

Abstract
Tamoxifen, as a standard treatment of estrogen receptor (ER)-positive breast cancer, reduces breast cancer mortality by 31%. In 50% of advanced ER-positive cancers, however, de novo resistance exists and in 40% of patients with initial response acquired resistance frequently evolves. In order to explore mechanisms underlying endocrine therapy resistance in breast cancer and to identify new opportunities to treat patients, we created seven tamoxifen-resistant breast cancer cell line models that represent the luminal A subtype (MCF-7, T-47D, ZR-75-1), which expresses ER, and the luminal B subtype (BT-474), which additionally expresses the HER2 oncoprotein. We then performed drug sensitivity and resistance testing (DSRT), exome-sequencing and network analysis on all these cancer cell lines to determine the molecular and drug response profiles specific to tamoxifen resistance. As the cells became tamoxifen-resistant, we observed increasing sensitivity towards drugs like ERK1/2-, proteasome- and BCL-family inhibitors, but each of the isogenic cell line pairs had its distinct genomic and drug response profile. We then studied the molecular profiles of the 7 drug-resistant variants by RNA-sequencing in comparison to their 4 isogenic parental cells. We could not detect any common significantly differentially expressed genes (more than 2 fold change) across all the cell lines. However, the cell lines could be grouped into two different categories: The ones with low amount of differentially expressed genes, &lt; 800 genes in the BT-474 and ZR-75-1 cell line pairs (with a 1,2% overlap), and the ones with high amount of differentially expressed genes, &gt;1800 genes in T-47D and MCF-7 (with 7,3% overlap). Further analysis with the Ingenuity pathway analysis tool revealed an involvement of “Fatty Acid Activation” as well as “Stearate Biosynthesis I” in this group. Additionally, we discovered that genes involved in iron metabolism (TFRC, IREB2 and FTL) or iron-regulated genes like CP and NDRG1 are deregulated. These genes and pathways thereby provide avenues to identify new drug vulnerabilities for the tamoxifen resistant cancer cells, which we are now investigating at gene and protein level e.g. by image-based phenotyping. In summary, by combining drug testing data with the RNA-sequencing results, we hope to provide a number of potential drugs as well as matching biomarkers for planning clinical trials for patients with tamoxifen-resistant breast cancer.
Citation Format: Susanne Hultsch, Sara Kangaspeska, Matti Kankainen, Vilja Pietiäinen, Olli Kallioniemi. Systematic drug testing and RNA-sequencing of tamoxifen resistant breast cancer cell lines. [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 2935.
Abstract 2937: Expression of osteopontin splicing isoforms in prostate cancer cells resistant to docetaxel
Authors: Menezes Mariana Concentino , O’Neil Amanda , Guimaraes Isabella , Rangel Letícia , Gimba Etel Rodrigues Pereira 
Published: July 2016

Abstract
Resistance to chemotherapeutic drugs corresponds to main causes of treatment failure. Total osteopontin (OPN) has been described as a gene product involved on chemoresistance, besides activating several aspects of tumor progression. OPN regulates the expression of P-glycoprotein (P-gp) in prostate cancer (PCa) cells, besides promoting apoptosis evasion induced by chemotherapy using paclitaxel and estramustin. These data point OPN as a potential therapeutic target to approaches that could reduce chemotherapy tumor resistance. However, most of this data are related to total OPN. Once OPN suffers alternative splicing, producing 3 isoforms, further investigation should demostrate their specific involvement on chemoresistance. Recent data from our group indicated that OPNb and OPNc splicing isoforms activate PCa tumor progression features. Besides, PCa cells that overexpress these splice variants are more resistant to apoptosis induced by docetaxel (DXT). The current work aims to investigate the expression pattern of OPN splicing isoforms (OPN-SIs) and their relationships in DXT-PCa resistant cells. Total RNA has been extracted from PCa cell lines resistant to DXT (PC3-D8 and PC3-D12) and PC3 control cells with similar cell passages (PC3-Ag). Then, cDNa has been synthesized. OPN-SI expression levels were analyzed by quantitative real time PCR (qRT-PCR) using SYBR Green and isoform specific oligonucleotides. Relative expression levels were calculated using ΔΔCT method. Among the 3 OPN-SIs, we observed that OPNb and OPNc variants are overexpressed in relation to OPNa in DXT-PCa resistant cells PC3-D8 and PC3-D12, when compared to PC3-Ag. PC3-D12 cell line, resistant to higher DXT concentrations, expresses higher levels of OPNc, when compared to the other cell lines. Overall, our data further evidence that OPNb and OPNc overexpression in DXT-PCa resistant cells could be involved on resistance to DXT. Functional assays will be performed in order to investigate the molecular mechanisms by which these OPN-SIs mediate resistance to this chemotherapeutic drug.
Citation Format: Mariana Concentino Menezes, Amanda O’Neil, Isabella Guimaraes, Letícia Rangel, Etel Rodrigues Pereira Gimba. Expression of osteopontin splicing isoforms in prostate cancer cells resistant to docetaxel. [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 2937.