bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 2321: Rapid induction of apoptosis by PI3K inhibitors is dependent upon their transient inhibition of RAS signaling.
Authors: Will Marie , Toy Weiyi , Yao Zhan , Poulikakos Poulikos , Rodrik-Outmezguine Vanessa , Schneider Claudia , Paul Juliane , Baselga Jose , Liu Ningshu , Rosen Neal , Chandarlapaty Sarat
Published: August 2014

Hyperactivation of the PI3K/AKT/mTOR pathway in tumors causes feedback inhibition throughout the signaling network, including inhibition of receptor tyrosine kinase (RTK) expression and function. Exposure of these tumors to mTOR or AKT inhibitors relieves this feedback and reactivates RTK signaling. RTK reactivation promotes PI3K activity and attenuates the antitumor effects of the drugs. We have now characterized the details of PI3K-induced feedback using a selective class 1 PI3K inhibitor and compared its effects with those elicited by a selective allosteric inhibitor of AKT. In breast cancer cell lines with dysregulation of PI3K signaling, both drugs cause marked inhibition of AKT phosphorylation and relief of feedback inhibition of HER3, IGF1, and insulin RTKs. Whereas both inhibitors cause tumor cells to undergo growth arrest, only the PI3K inhibitor causes a rapid induction of apoptosis within 2 hours of drug addition. As opposed to the PI3K inhibitor, the AKT inhibitor induces PI3K activity and a set of substrates that are inhibited by the PI3K inhibitor. We therefore sought to identify processes that are selectively inhibited by the PI3K inhibitor to explain its selective induction of apoptosis.

AKT inhibition causes the induction of ERK phosphorylation in these cells. In contrast, we found that PI3K inhibition causes rapid inhibition of RAS-GTP levels, RAF activation and ERK phosphorylation in tumor cells with wild type RAS, but not those with mutant RAS. Inhibition of RAS is transient, recovering 2-3 hours after drug addition. We determined that adding MEK inhibitors to AKT inhibitors is similarly associated with a rapid induction of apoptosis within 2 hours. Moreover, addition of EGF to tumor cells co-treated with PI3K inhibitors prevents ERK inhibition and apoptosis, whereas addition of MEK inhibitors to the PI3K inhibitor, EGF treated cells restores the apoptotic phenotype.

We conclude that PI3K is upstream of both RAS and AKT in RAS wild type tumors. Inhibitors of PI3K cause sustained inhibition of AKT and transient inhibition of RAS with both effects required for rapid induction of apoptosis. These data suggest that pulsatile inhibition of PI3K may maximize the therapeutic efficacy of this approach.

Citation Format: Marie Will, Weiyi Toy, Zhan Yao, Poulikos Poulikakos, Vanessa Rodrik-Outmezguine, Claudia Schneider, Juliane Paul, Jose Baselga, Ningshu Liu, Neal Rosen, Sarat Chandarlapaty. Rapid induction of apoptosis by PI3K inhibitors is dependent upon their transient inhibition of RAS signaling. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2321. doi:10.1158/1538-7445.AM2013-2321
Abstract 2330: NSC319726 reactivates zinc-binding p53 mis-sense mutants using a novel dual mechanism.
Authors: Yu Xin , Lubin David , Narayanan Sumana , Vazquez Alexei , Loh Stewart , Levine Arnold J. , Carpizo Darren R.
Published: August 2014

TP53 is the most commonly mutated gene in human cancer for which no effective targeted anti-cancer drug exists. We identified NSC319726 (726) as a mutant p53 reactivating compound, and a lead compound for mutant p53 targeted drug development. Prior evidence indicated that the effects of 726 were allele-specific, by restoring wildtype structure and function to the third most common p53 mis-sense mutant (p53-R175H). This effect was dependent on the zinc-chelating and redox modulating properties of 726. The p53 protein binds a single zinc ion which is necessary for proper p53 structure and function. The p53-R175H mutation impairs the protein from binding zinc causing it to mis-fold and lose transcriptional function. We have investigated these properties of 726 in the mechanism of p53-R175H reactivation and provide evidence for a novel “dual” mechanism where 726 restores wild-type structure to the p53-R175H using a zinc-metallochaperone function to provide an optimal concentration of zinc to facilitate proper folding. We also demonstrate that the redox modulating properties of 726 function to transactivate the newly conformed p53-R175 and induce an apoptotic program. Lastly, we demonstrate that this zinc-metallochaperone function applies to other p53 mis-sense mutants with impaired zinc binding. This later finding extends the potential pool of patients that could be impacted by the clinical development of 726 as a mutant p53 targeted anti-cancer drug.

Citation Format: Xin Yu, David Lubin, Sumana Narayanan, Alexei Vazquez, Stewart Loh, Arnold J. Levine, Darren R. Carpizo. NSC319726 reactivates zinc-binding p53 mis-sense mutants using a novel dual mechanism. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2330. doi:10.1158/1538-7445.AM2013-2330
Abstract 234: Inhibition of the NOTCH transcription factor complex by a novel hybrid protein leads to effective tumor therapy.
Authors: Epenetos Agamemnon A. , Kousparou Christina , Stylianou Spyros , Deonarain Mahendra , Filipovic Aleksandra
Published: August 2014

The Notch pathway has been implicated in the generation and propagation of cancer stem cells and is thus an attractive target for therapy. We have generated a hybrid protein (Antp-DNMAML) consisting of the truncated version of Mastermind-like (MAML) that behaves in a dominant negative (DN) fashion inhibiting Notch, and the cell penetrating peptide Antennapedia (Antp). Results indicate that the Antp-DNMAML translocates into the nucleus, suppresses Notch activation, reverts the transformed phenotype, inhibits the anchorage-dependent growth and induces self contact inhibition and apoptosis in tumorigenic human breast cancer cells. More significantly, there is direct evidence that inhibiting Notch signaling at the transcriptional level with the Antp-DNMAML protein, suppresses the expression of downstream Notch targets and inhibits tumor growth in nude mice, without organ or systemic toxicity. In summary, intracellular delivery of dominant-negative transcription complex proteins using the Antp platform is a new and specific approach for cancer therapy .

Citation Format: Agamemnon A. Epenetos, Christina Kousparou, Spyros Stylianou, Mahendra Deonarain, Aleksandra Filipovic. Inhibition of the NOTCH transcription factor complex by a novel hybrid protein leads to effective tumor therapy. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 234. doi:10.1158/1538-7445.AM2013-234
Abstract 2346: A B-RAF-MEK complex reveals a kinase-independent role for BRAF in MAPK pathway suppression.
Authors: Shiva Malek , Haling Jacob R. , Sudhamsu Jawahar , Morales Tony , Peck Ariana , Yen Ivana , Brandhuber Barbara , Hymowitz Sarah
Published: August 2014

The Ras/RAF/MEK/ERK signaling pathway (MAPK pathway) plays a major role in growth factor-mediated cell proliferation and is frequently activated by mutation in human cancers. The precise mechanism of pathway activation is dependent on the underlying mutation. Thus, the recurrent B-RAFV600E mutation, which is found in more than 60% of melanomas, promotes MAPK pathway signaling independent of RAS activation whereas activating K-RAS mutations drive MAPK signaling through C-RAF activation. The hallmarks of C-RAF activation include B and C-RAF heterodimerization, membrane localization and C-RAF phosphorylation. In this work, we have discovered that in addition to its ability to activate the pathway through B-RAF/C-RAF dimerization, B-RAF suppresses the MAPK pathway through formation of a stable B-RAF/MEK complex in the cytoplasm of B-RAFWT and K-RAS mutant (K-RASMT) tumor lines. To understand the molecular mechanism of the B-RAF/MEK interaction, we have determined the crystal structure of a heterotetrameric B-RAF:MEK1 complex in which B-RAF and MEK1 form a face-to-face dimer with B-RAF side-to-side dimers at the heart of the complex. Structural and biochemical evidence illustrate that the molecular determinants for B-RAF enzymatic activity is distinct from those required for interaction with MEK. Our work also reveals the molecular basis for the paradoxical ability of both BRAF-activating and -inactivating oncogenic mutations to stimulate the MAPK pathway. Taken together, these findings reveal a novel regulatory role for B-RAF in the MAPK pathway that is independent of its catalytic activity but dependent on the conformation of the B-RAF kinase domain.

Citation Format: Malek Shiva, Jacob R. Haling, Jawahar Sudhamsu, Tony Morales, Ariana Peck, Ivana Yen, Barbara Brandhuber, Sarah Hymowitz. A B-RAF-MEK complex reveals a kinase-independent role for BRAF in MAPK pathway suppression. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2346. doi:10.1158/1538-7445.AM2013-2346
Abstract 2356: Biomarkers of progressive squamous lung dyplasia.
Authors: Friedman Micah , Tennis Meredith , Dwyer-Nield Lori , Keith Robert , Nemenoff Raphael , Franklin Wilbur , Geraci Mark , Edwards Michael , Michio Sugita , Merrick Dan
Published: August 2014

Lung cancer is the leading cause of cancer death in the United States. Squamous cell lung cancers (SCC) comprise approximately 30% of lung cancer cases, and 48,000 people are projected to die this year in the U.S. from SCC. Bronchial dysplasia (BD) is a precursor of SCC, however not all BDs progress to carcinoma. Persistent or progressive BD is associated with a higher risk for the development of invasive lung cancer. We hypothesize that characterization of the difference between persistent and regressive BD will identify high risk patients and suggest novel therapeutic targets for prevention of progression to lung SCC. Gene expression analysis was used to identify differences between persistent and regressive BD. Subjects recruited to Colorado SPORE in Lung Cancer screening studies that met sputum atypia criteria and underwent multiple bronchoscopies were evaluated. Sixty-three frozen baseline biopsies showing BD by histology were classified as persistent/progressive (group 1) or regressive (group 2) according the presence or absence of BD on follow-up biopsies at the same sites. H&E staining was performed on frozen sections to confirm histology, and RNA was harvested and used to create gene expression arrays. PLK1 was selected as a gene of interest based on significantly increased levels of expression and pathway analyses implicating increased activity of cellular pathways associated with PLK-1 expression. Additionally, bronchial epithelial cells were cultured from fresh biopsies taken immediately adjacent to persistent or regressive bronchial sites, and RNA, DNA, and protein were harvested. qRT-PCR was performed on RNA extracted from these persistent and regressive biopsy epithelial cultures. PLK1 expression in epithelial cultures was shown to be increased in persistent as compared to regressive cell lines suggesting that this cell cycle control enzyme may represent a possible chemoprevention target in persistent/progressive dysplasias. RNA was also extracted from a variety of immortalized cancer cell lines of both squamous and adenocarcinoma subtypes, and qRT-PCR was used to establish baseline expression of these genes in cancer cells. Eleven of 20 lung cancer cell lines showed at least 20 fold higher PKL-1 expression compared to non-tumorigenic cell lines while 4 out of 4 lines of SCC origin showed 75 fold or higher expression further supporting a role for this enzyme in SCC progression.

Citation Format: Micah Friedman, Meredith Tennis, Lori Dwyer-Nield, Robert Keith, Raphael Nemenoff, Wilbur Franklin, Mark Geraci, Michael Edwards, Sugita Michio, Dan Merrick. Biomarkers of progressive squamous lung dyplasia. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2356. doi:10.1158/1538-7445.AM2013-2356
Abstract 2357: Prognostic value of placental growth factor expression in patients with metastatic or recurrent non-small cell lung cancer.
Authors: Kim Jung Hoon , Kim Tae Jung , Lee Kyu Sang , Jung Yun Hwa , Woo In Sook , Hong Sook Hee , Han Chi Wha , Park Jae Kil , Byun Jae Ho
Published: August 2014

Background: Placental growth factor (PIGF) is a proangiogenic factor, belonging to the VEGF family. It binds to VEGF receptor 1(VEGFR-1) and stimulates the growth, migration and survival of endothelial cells. PIGF also activates and attracts macrophages that release angiogenic molecules. Increased expression of PIGF has correlated with poor survival of patients in several solid tumors. However, PIGF expression is not consistently elevated in all malignancies. No reports on the clinical implications of PIGF expression in metastatic or recurrent non-small cell lung cancer (NSCLC) are currently available. We investigate the clinical significance of PIGF expression in metastatic or recurrent NSCLC.

Patients and methods: A retrospective review was done for seventy four patients with metastatic or recurrent NSCLC. Immunohistochemical staining for PIGF and its receptor VEGF-R1, neurophilin-1 was performed. Results: Of 74 patients with NSCLC, 73 patients were positive for PIGF, and 72 patients were positive for neurophilin-1. For PIGF expression, significant correlations were demonstrated with female (p=0.007) and nonsquamous histology (p=0.045). Thirty five patients (47%) were classified into low PIGF expression groups, whereas 38 patients (51%) were grouped as showing high PIGF expression. Survival time for patients with high PIGF expressing NSCLC was significantly longer than that for patients displaying low PIGF expression (median survival time, 15.1 months vs. 9.0 months[log-rank, p=0.01]). However, the difference in time to progression between two groups was not statistically significant (median time to progression, 5.1 months vs. 3.9 months [log-rank, p=0.24]).

Conclusions: Low expression of PIGF is associated with poor prognosis in patients with metastatic or recurrent NSCLC. Further studies on larger patients populations are warranted to validate the utility of PIGF as a prognostic biomarker in lung cancer.

Citation Format: Jung Hoon Kim, Tae Jung Kim, Kyu Sang Lee, Yun Hwa Jung, In Sook Woo, Sook Hee Hong, Chi Wha Han, Jae Kil Park, Jae Ho Byun. Prognostic value of placental growth factor expression in patients with metastatic or recurrent non-small cell lung cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2357. doi:10.1158/1538-7445.AM2013-2357
Abstract 2372: Predictive markers in patients with non-small cell lung cancer with pemetrexed treatment.
Authors: Chae Hiun S. , Ko Yoon Ho , Jeon Eun Kyoung , Hong Sook Hee , Kim Jeong-Oh , Kim Seung Joon , Lee Kyo Young , Kim Young Kyoon , Kim HoonKyo , Park Seok young , Woo In Sook , Kang Jin Hyoung
Published: August 2014

Background: This study is desiged to evaluate biomarkers that are correlated with the efficacy of pemetrexed in patients with non-small-cell lung cancer (NSCLC).

Methods: Patients with stage III or IV NSCLC who received pemetrexed monotherapy after failure of one or more chemotherapy regimen between January 2003 and August 2011 were included. Polymorphism of reduced folate carrier gene (SLC19A, rs1051298), 5,10-methylenetetrahydroflate reductase (MTHFR, rs1801133) and thymidylate synthase (TS, rs45445694, rs16430) gene were analyzed by PCR and direct sequencing method using peripheral blood.

Results: Total 123 patients were included. The median age was 61 years (range 35-82). Fifty eight (47.2%) patients were female. Predominant histology was adenocarcinoma (92.7%). Metastatic diseases were 114 (80.5%) patients. Patients received one or more lines of systemic therapy before pemetrexed therapy, one line in 53 (43.1%) patients, two in 51(41.5%), three in 14 (11.02%), and four in 4 (3.3%). Median 4 cycles of chemotherapy were given (range 1-44). Response rate was 22.7% (CR, n=2, PR, n=26) and stable disease was detected in 54 patients (43.9%). Median follow up duration was 28.7months (range 4.07-84.33months). Median progression free survival (PFS) was 4.2 months (95% CI: 2.9-5.6) and median overall survival (OS) was 18.9 months (95% CI: 13.3-24.6). Clinical factors like, sex, histology of tumor (adenocarcinoma vs, nonadenocarcinoma), differentiation, smoking status and EGFR mutation status (active mutation vs. other mutation vs. wild type) did not have any significant difference on response and PFS. Only polymorphisms of TS promoter enhancer region (TSER) were related with PFS. 2R/2R repeat in the TSER (2R/2R vs 2R/3R, 3R/3R 1.0m vs 4.3m, p<0.01) and CC homozygote variant in second repeat of the 3R allele (CC vs GC, GG 2.8m vs 5.0m, p=0.04) had poor PFS. All polymorphism did not have effect on response rate and overall survival.

Conclusions: This study suggests that polymorphisms of TSER associated PFS in pemetrexed treatment. Further prospective studies will be needed to validate these polymorphism as a useful biomarker of pemetrexed treatment in NSCLC patients.

Citation Format: Hiun S. Chae, Yoon Ho Ko, Eun Kyoung Jeon, Sook Hee Hong, Jeong-Oh Kim, Seung Joon Kim, Kyo Young Lee, Young Kyoon Kim, HoonKyo Kim, Seok young Park, In Sook Woo, Jin Hyoung Kang. Predictive markers in patients with non-small cell lung cancer with pemetrexed treatment. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2372. doi:10.1158/1538-7445.AM2013-2372
Abstract 2373: The LCBRN: a biospecimen resource for lung cancer biomarker and discovery science.
Authors: Moskaluk Christopher A.
Published: August 2014

The Lung Cancer Biospecimen Resource Network (LCBRN) is an open access biorepository that obtains specimens from lung cancer patients (tissue, blood, urine, bronchial lavage fluid and saliva) and makes them available to biomedical researchers. Specimen collection is supported at 3 collection sites (Medical University of South Carolina, The University of Virginia, and Washington University at St. Louis) in compliance with uniform standard operating procedures. The specimens are annotated with clinical, radiologic and pathologic data. Histologic and molecular quality control procedures are in place for tissue samples. Lung cancer and non-neoplastic lung tissue aliquots are processed into DNA, RNA and protein fractions, which are also available. Fluid biosamples are available from subjects prior to, and after surgery to remove the cancer. A cohort of subjects are followed for recurrence with serial biofluid sampling. Specimens are currently available from over 300 research subjects. The application form for biospecimens and additional information is available at http://LCBRN.org.

Citation Format: Christopher A. Moskaluk. The LCBRN: a biospecimen resource for lung cancer biomarker and discovery science. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2373. doi:10.1158/1538-7445.AM2013-2373
Abstract 2387: Activation of Inhibin A signaling is associated with a basal-like HER2 subtype and resistance to lapatinib in breast cancer cell lines.
Authors: Korkola James E. , Rantala Juha , Bayani Nora , Heiser Laura , Wang Nicholas , Griffith Obi , Gray Joe
Published: August 2014

HER2 amplification occurs in ∼20% of all breast cancers, and is associated with poor prognosis. Targeted therapeutics such as trastuzumab and lapatinib have been developed and have improved outcomes for patients with HER2+ disease. However, a significant proportion of patients have tumors that either develop resistance or simply fail to respond to these therapies at all. To better understand the mechanism of resistance, we screened a panel of 22 HER2+ breast cancer cell lines with lapatinib. Of these, 6 showed significant resistance, failing to reach 50% growth inhibition (GI50) even at 5uM, the highest dose tested. The resistant lines were all more basal-like in expression patterns, and were more responsive to MEK inhibitors than their luminal-like counterparts. These two patterns of expression are similar to the different HER2 subtypes recently identified by the TCGA project. Differential expression analysis utilizing t-tests with Benjamini-Hochberg correction for multiple comparisons identified approximately 150 transcripts that were more highly expressed in resistant cell lines. We performed high-throughput screening using siRNA knockdown of the target genes in combination with lapatinib treatment. Staining for markers of proliferation (Ki67), apoptosis (cleaved PARP), and activity of the PI3K-AKT pathway showed that silencing of inhibin A resulted in a decrease in the ratio of proliferative to apoptotic cells in the resistant cell lines 21-NT and 21-PT. Concurrent with this decrease was a down-regulation of both p-MAPK and p-AKT. GO analysis revealed a strong enrichment for Inhibin A signaling amongst the 150 resistance associated transcripts. Mining of tumor databases revealed that there was a trend between high levels of Inhibin A expression and poor outcome in HER2 positive tumors (p=0.08). These data suggest that activation of Inhibin A signaling is associated with a more basal like subclass of HER2+ tumors, resistance to HER2 targeted therapeutics such as lapatinib, and that corresponding over-expression of Inhibin A is associated with poor outcome in HER2+ patients.

Citation Format: James E. Korkola, Juha Rantala, Nora Bayani, Laura Heiser, Nicholas Wang, Obi Griffith, Joe Gray. Activation of Inhibin A signaling is associated with a basal-like HER2 subtype and resistance to lapatinib in breast cancer cell lines. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2387. doi:10.1158/1538-7445.AM2013-2387
Abstract 244: Cancer stem cells predict engraftment and poor prognosis of primary breast tumor.
Authors: Charafe-Jauffret Emmanuelle , Ginestier Christophe , Bertucci Francois , Cabaud Olivier , Adelaide Jose , Chaffanet Max , Xerri Luc , Viens Patrice , Birnbaum Daniel
Published: August 2014

Despite the promise of the cancer stem cell (CSC) model, its clinical relevance remains to be proven in breast cancer (BC) and requires a sensitive xenograft assay to define CSC on key functional properties i.e tumorigenicity, self-renewal and differentiation potential.

We report the establishment of primary breast tumor-derived xenografts (PDXs) that retain main primary tumors features (histo-phenotypic, molecular and genomic features, hierarchical organization of the tumoral cell population). We demonstrate that success in engraftment is correlated with the presence of CSC in primary tumor and predicts prognosis in patients (HR= 3.61; 95%CI [1.12-11.65], p=3.20E-02).

The xenograft assay demonstrated the hierarchical organization of BC. Analysis of gene expression from functionally validated CSC yield to a breast CSC signature (BCSC-GES) is an independent predictor of patient survival. We then identified a core of genes commonly expressed by BCSC and embryonic, hematopoietic, neural stem cells, the CE-4SC. This shared transcriptional program comprised 19 genes encoding mismatch and nucleotide excision repair proteins, proteins implicated in transport through the endoplasmic reticulum, RNA processing, translation and transcriptional regulators, enzymes of detoxification and mitochondrial/oxidative stress, or enzymes of lipid metabolism. This “universal” stem cell program is also an independent predictor of patient survival.

Using a screening of an RNA-interference library specially designed to block the expression of these 19 target genes, we validated the effect of single gene knock-down (KD) on the breast CSC population for 14 genes (KD of 5 genes decreased the CSC population and were called “self-renewers”genes, KD of 9 genes increased the CSC, and were designated as“differentiators”).

Hence, this study validated the clinical relevance of CSC model in breast cancer for the first time, and the ability of PDXs to accelerate transfer for personalized CSC therapy into clinics.

Citation Format: Emmanuelle Charafe-Jauffret, Christophe Ginestier, Francois Bertucci, Olivier Cabaud, Jose Adelaide, Max Chaffanet, Luc Xerri, Patrice Viens, Daniel Birnbaum. Cancer stem cells predict engraftment and poor prognosis of primary breast tumor. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 244. doi:10.1158/1538-7445.AM2013-244
Abstract 2449: The bromodomain inhibitor JQ1 blocks growth of pancreatic cancer cells in 3D collagen.
Authors: Sahai Vaibhav , Kumar Krishan , Ebine Kazumi , Nimeiri Halla , Munshi Hidayatullah G.
Published: August 2014

Pancreatic ductal adenocarcinoma (PDAC) is associated with a pronounced collagen-rich stromal reaction that has been shown to contribute to chemo-resistance. We have found that the collagen microenvironment promotes expression of histone acetyltransferases (HATs) and thereby promotes chemo-resistance; however, HATs have proven to be difficult ‘druggable’ targets. Bromodomain proteins are chromatin readers that can bind to acetylated histones and thereby regulate gene expression. JQ1, an inhibitor of BET class of human bromodomains, was shown to have efficacy against leukemia and lymphoma cell lines. Thus, we examined the effect of JQ1 on a panel of PDAC cells grown in 3D collagen. AsPC1, CD18 and Panc02.03 cells were particularly sensitive to the effects of JQ1, while Panc1 cells were relatively resistant to JQ1 treatment. JQ1 decreased myc mRNA and increased p21 mRNA in CD18 cells, but not in Panc1 cells. JQ1 also decreased growth of chemo-resistant CD18 cells grown in 3D collagen, and blocked EGF and TGF-β1-induced growth and scattering of Panc1 and CD18 cells in 3D collagen. The MEK1/2 inhibitor U0126 and JQ1 synergistically attenuated growth of CD18 and Panc1 cells in 3D collagen. In addition, EGFR inhibitors (AG1478 and PD153035) and JQ1 also synergistically attenuated the growth of CD18 and Panc1 cells in 3D collagen. In contrast, the p38 MAPK inhibitor SB202190 did not attenuate the effect of JQ1 on growth of CD18 and Panc1 cells in 3D collagen. Finally, JQ1 potentiated the effect of gemcitabine on the growth of CD18 and Panc1 cells in 3D collagen. Overall, these results suggest that JQ1 and other bromodomain inhibitors are potential therapeutic agents for the treatment of pancreatic cancer.

Citation Format: Vaibhav Sahai, Krishan Kumar, Kazumi Ebine, Halla Nimeiri, Hidayatullah G. Munshi. The bromodomain inhibitor JQ1 blocks growth of pancreatic cancer cells in 3D collagen. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2449. doi:10.1158/1538-7445.AM2013-2449
Abstract 2456: Discovery of orally active 4-amino-6-arylaminopyrimidine-5-carbaldehyde oximes with dual EGFR and HER2 inhibitory activity.
Authors: Connolly Peter J. , Adams Mary , Beck Amanda K. , Emanuel Stuart L. , Fuentes-Pesquera Angel R. , Greenberger Lee M. , Gruninger Robert H. , Hughes Terry V. , Middleton Stephen A. , Moreno-Mazza Sandra , Pandey Niranjan , Wetter Steven K. , Xu Guozhang
Published: August 2014

Growth factor receptors of the ErbB family, especially ErbB1 (EGFR) and ErbB2 (HER2), have attracted considerable attention in recent years as therapeutic targets for the treatment of numerous malignancies including cancers of the lung, colon, and breast, either through blockade of the extracellular ligand binding site by monoclonal antibodies (e.g. anti-EGFR antibodies cetuximab and panitumumab, and anti-HER2 antibody trastuzumab) or inhibition of the intracellular tyrosine kinase domain by small molecule inhibitors (e.g. EGFR kinase inhibitors gefitinib and erlotinib, and dual EGFR/HER2 inhibitor lapatinib). The abundance of small molecule kinase inhibitors in clinical development or on the market attests to the acceptance of ErbB inhibition as a clinically relevant paradigm. Nevertheless, the emergence of resistance mechanisms in ErbB driven or dependent tumors indicates that continued research is required to discover more effective drugs. We previously reported the discovery of JNJ-28871063, a potent inhibitor of EGFR and HER2 kinases in vitro that also showed excellent antitumor efficacy in EGFR (A431 epidermoid carcinoma) and HER2 (N87 gastric carcinoma) overexpressing xenograft models and significant extension of survival in a mouse intracranial tumor model. This compound is a 4-amino-6-arylaminopyrimidine-5-carbaldehyde oxime, a monocyclic chemotype that mimics the traditional bicyclic quinazoline scaffold via an intramolecular hydrogen-bonded pseudocycle involving the adjacent 4-amino and 5-oximino groups. In this study, we present results of a structure-guided analog program designed to optimize in vitro kinase potency and in vivo antitumor efficacy of the pyrimidine-oximes. While substituents on the 6-arylamino group are critical for ErbB inhibitory potency and kinase selectivity, substitution on the oxime oxygen may be changed to modify physico-chemical properties and bioavailability. We will discuss structure-activity relationships for the 5-oximino and 6-arylamino groups as well as the important role played by O-aminoalkyl oxime substituents in improving in vivo activity.

Citation Format: Peter J. Connolly, Mary Adams, Amanda K. Beck, Stuart L. Emanuel, Angel R. Fuentes-Pesquera, Lee M. Greenberger, Robert H. Gruninger, Terry V. Hughes, Stephen A. Middleton, Sandra Moreno-Mazza, Niranjan Pandey, Steven K. Wetter, Guozhang Xu. Discovery of orally active 4-amino-6-arylaminopyrimidine-5-carbaldehyde oximes with dual EGFR and HER2 inhibitory activity. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2456. doi:10.1158/1538-7445.AM2013-2456
Abstract 2457: Ex vivo analysis of novel isoflavanoids (ME-143 and ME-334) in patient derived triple negative breast cancer tumors.
Authors: Praveen Kesavan Nair , Broudy Thomas , Mirsaidi Cyrus , Moreno Ofir , Gold Daniel
Published: August 2014

There is an unmet need for novel effective therapeutics to treat triple negative (ER, PR and Her2 negative) breast cancer in clinics. Phase I clinical studies of 2 novel isoflavonoid investigational drugs, ME-143 and ME-344 have been shown them to be generally well tolerated in patients with solid tumors. ME-143, a next analogue of the investigational anti-cancer drug Phenoxodiol binds at low nanomolar concentrations to a tumor-specific variant of cell surface associated NADH oxidase (tNOX), resulting in caspase activation and apoptotic tumor cell death. ME-344, a second investigational anti-cancer isoflavonoid, is structurally related to ME-143 but functionally distinct. ME-344 is a mitochondrial targeting agent that interferes with tumor cell energy generation resulting in cell death via mitochondrial membrane destabilization and autophagy induction through the disruption of both mTOR1 and mTOR2 upstream and downstream signal transduction pathways. Pre-clinical studies using in vitro cell lines showed significantly high potency for both compounds either when used as single agents or when combined with cytotoxic and targeted anti-cancer agents. The present study investigated the ex vivo efficacy of ME-143 and ME-344 using patient-derived tumor cells from triple negative breast cancer. Tumor tissue was disintegrated into single cell suspension and expanded in mouse as subcutaneous patient-derived xenograft before harvesting for the studies. Mouse tumor cells were disintegrated into single cells and were grown as spheroids to mimic the tumor micro-environment and single agent as well as combination treatments were performed. Using a high content imaging platform, various endpoints were evaluated to compare the efficacies of the drugs. Both ME-143 and ME-344 as single agents showed efficacy in inhibiting cell proliferation as well as colony formation in patient-derived triple negative breast cancer cells while combination of these agents with Cisplatin and Gemcitabine demonstrated additive or synergistic effects. Use of high content imaging has enabled the identification of patient population that has tumor cells resistant to very high doses of drugs. Follow-up studies are planned to characterize the sub-population of cells that are resistant to high dose of these drugs.

Citation Format: Kesavan Nair Praveen, Thomas Broudy, Cyrus Mirsaidi, Ofir Moreno, Daniel Gold. Ex vivo analysis of novel isoflavanoids (ME-143 and ME-334) in patient derived triple negative breast cancer tumors. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2457. doi:10.1158/1538-7445.AM2013-2457
Abstract 246: Role of the IL-6-JAK1-STAT3-Oct-4 pathway in the dynamic equilibrium between cancer stem cells and non-stem cancer cells.
Authors: Kim Seog-Young , Kang Jin W. , Kim Bokyoung , Yoo Young D. , Kwon Yong T. , Lee Yong J.
Published: August 2014

Previous studies have demonstrated that a small subset of cancer cells is capable of tumor initiation. The existence of tumor initiating cancer stem cells (CSCs) has several implications in terms of future cancer treatment and therapies. However, recently, several researchers proposed that differentiated cancer cells (non-CSCs) can convert to stem-like cells to maintain equilibrium. These results imply that removing CSCs may prompt non-CSCs in the tumor to convert into stem cells to maintain the equilibrium. Interleukin-6 (IL-6) has been found to play an important role in the inducible formation of CSCs and their dynamic equilibrium with non-stem cells. In this study, we used CSC-like MDA-MB231 human breast adenocarcinoma cells and their alternate subset non-CSCs to investigate how IL-6 regulates the conversion of non-CSCs to CSCs. CSC-like cells formed mammospheres well, whereas most of non-stem cells died by anoikis and only part of the remaining non-stem cells produced viable mammospheres. Similar results were observed in xenograft tumor formation. Data from cytokine array assay show that IL-6 was secreted from non-CSCs when cells were cultured in ultra-low attachment plates. IL-6 regulates CSC-associated OCT-4 gene expression through the IL-6-JAK1-STAT3 signal transduction pathway in non-CSCs. Inhibiting this pathway by treatment with anti-IL-6 antibody (1 μg/ml) or niclosamide (0.5-2 μM)/LLL12 (5-10 μM) effectively prevented OCT-4 gene expression and suppressed mammosphere formation of non-stem cells. These results suggest that the IL-6-JAK1-STAT3 signal transduction pathway plays an important role in the conversion of non-CSCs into CSCs through regulation of OCT-4 gene expression.

Citation Format: Seog-Young Kim, Jin W. Kang, Bokyoung Kim, Young D. Yoo, Yong T. Kwon, Yong J. Lee. Role of the IL-6-JAK1-STAT3-Oct-4 pathway in the dynamic equilibrium between cancer stem cells and non-stem cancer cells. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 246. doi:10.1158/1538-7445.AM2013-246
Abstract 2466: Characterization and development of on-target Mcl-1 inhibitors; BH3 profiling provides a valuable drug discovery tool.
Authors: Richard David J. , Carlson Nicole , Pierceall William , Lena Ryan , Bannister Thomas , Hodder Peter , Spicer Timothy , Andreeff Michael , Opferman Joseph , Koss Brian , Kung Andrew , Cardone Michael
Published: August 2014

Anti-apoptotic Bcl-2 family proteins are central to the regulation of the intrinsic apoptotic pathway, and as such constitute an important group of targets with great potential as oncology therapeutics. The Bcl-2 family protein Mcl-1 has been demonstrated to facilitate survival and chemoresistance in multiple myeloma, AML, and other cancers, and agents which affect this pathway have become highly sought after. Currently, however, no therapies exist which directly target Mcl-1. We have identified compounds that target Mcl-1 which may be characterized as both Mcl-1-selective and pan-Mcl-1/Bcl-2 inhibitors. This effort has been facilitated by utilization of the BH3 profiling technology to guide SAR. This assay allows for determination of the mitochondrial priming state of both cell culture samples and primary patient samples. We have demonstrated a correlation between myeloma and leukemia cell line response to treatment with our inhibitors and the mitochondrial priming state of such cell lines. Such correlations have also been shown with respect to the extent of cytochrome C release. In the case of the selective Mcl-1 inhibitor, we have shown that cytochrome C release occurs preferentially in leukemia cell lines which are highly primed for Mcl-1 rather than Bcl-2. In addition, our Mcl-1 selective inhibitor demonstrates enhanced cell killing ability in leukemia cells which have been engineered to selectively express Mcl-1, Bcl-2, and Bcl-xL. Our current lead candidate possesses excellent drug-like properties and displays impressive efficacy in a multiple myeloma disseminated xenograft model. This work demonstrates the utility of the BH3 profiling assay as providing a functional biomarker for drug discovery tool and its ability to validate the on-target activity of Mcl-1 and Bcl-2 inhibitors.

Citation Format: David J. Richard, Nicole Carlson, William Pierceall, Ryan Lena, Thomas Bannister, Peter Hodder, Timothy Spicer, Michael Andreeff, Joseph Opferman, Brian Koss, Andrew Kung, Michael Cardone. Characterization and development of on-target Mcl-1 inhibitors; BH3 profiling provides a valuable drug discovery tool. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2466. doi:10.1158/1538-7445.AM2013-2466
Abstract 2500: Analysis of protein biomakers in prostate and colorectal tumor lysates.
Authors: Stephen Laurie L. , Damour Marc , Kemp Josh , Ballard Karri L. , McDade Ralph L. , Mapes James P.
Published: August 2014

Traditional tumor biomarkers are proteins that have been shed in the bloodstream and have been critical in identifying and treating cancer. We sought to survey proteins relevant to oncology in colon and prostate tumors; in order to identify potential proteins of interest for cancer research. Four colon and three prostate tumors were homogenized and 115 proteins were analyzed from the Oncology MAP 2.0. Each tumor had 2 fractions homogenized to look at heterogeneity of the protein with the tumor. In all of the samples measured 102 of the 115 protein showed levels above the LLOQ. Five proteins (PSP94, Tenascin-X, lipocalin-1, Tie-1 and BAFF) were 100 fold higher in prostate tumors compared to colon tumors (P<0.001). PSP94 has been shown to be a prostate cancer marker in serum; however, none of the other markers have been shown to be markers of prostate tumors. Eight proteins (PECAM-1, CA 72-4, Eotaxin-2, HGF-R, CA 15-3, TATI, CEACAM6 and CEA) were greater than 10 fold higher in colon tumors compared to prostate tumors (P<0.001). Although oncology MAP 2.0 was developed for serum biomarkers, it may provide a valuable tool for examining proteins biomarkers in tumors.

Citation Format: Laurie L. Stephen, Marc Damour, Josh Kemp, Karri L. Ballard, Ralph L. McDade, James P. Mapes. Analysis of protein biomakers in prostate and colorectal tumor lysates. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2500. doi:10.1158/1538-7445.AM2013-2500
Abstract 2501: Differential protein signatures in cancer cell lines after dosing with anticancer molecules in vitro and in vivo.
Authors: Swift Robert , Ayers Deb , Chang Ying , Perry Darryl , Routt Sheri , Wilcox Sheri , Lollo Bridget , Saccomano Nick
Published: August 2014

Using a sensitive proteomics platform that can precisely and simultaneously measure 1129 distinct proteins (SOMAscan™), we profiled the proteomic changes in cancer cell lines and xenograft models following exposure to several oncological agents. Our goals were to identify novel biomarkers and drug targets, and to map out pharmacological MOA, with the ultimate goal of assessing the translatability of in vitro and preclinical models to human patients. We have generated multiple successful examples of using our platform in this manner. We treated a breast cancer cell line MCF-7 with eight pharmacological agents, including TamoxifenTM and TaxolTM. We have assessed PKC-δ resistant and sensitive lung cancer cell lines with a PKC-δ inhibitor, and profiled protein changes in response to these compounds. To assess how well in vitro models translate to preclinical models, we profiled protein changes in HCC827 (sensitive) or H1299 (resistant) cell lines treated with erlotinib (TarcevaTM), and NOD/SCID mice implanted with HCC827 cells and dosed with erlotinib. We observed good concordance of the protein changes in the HCC827 cell-lines and the xenograft models, which included cyclin A and p27KIP1 expression levels (proteins previously associated with erlotinib sensitivity) as well as additional protein changes with highly plausible connections to erlotinib's mode of action. These newly identified proteins may have implications for treating patients that develop resistance to erlotinib in the clinic, and suggest new targets for drug development. A human clinical study is underway to explore how the proteomic changes seen in this study translate to erlotinib treatment of NSCLC patients in the clinic.

Citation Format: Robert Swift, Deb Ayers, Ying Chang, Darryl Perry, Sheri Routt, Sheri Wilcox, Bridget Lollo, Nick Saccomano. Differential protein signatures in cancer cell lines after dosing with anticancer molecules in vitro and in vivo. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2501. doi:10.1158/1538-7445.AM2013-2501

Note: This abstract was not presented at the AACR Annual Meeting 2013 because the presenter was unable to attend.
Abstract 2530: Incidence trends of childhood and adolescent melanoma in the United States from 1973-2009.
Authors: Wong Jeannette , Harris Jenine , Rodriguez-Galindo Carlos , Johnson Kimberly
Published: August 2014

OBJECTIVE: Melanoma in children and adolescents is rare but, similar to adults, has been reported to be increasing. To gain insight into possible reasons underlying increased number of cases, we analyzed trends in melanoma incidence diagnosed between the ages of 0-19 years among United States whites by sex, stage, age at diagnosis, and primary site. We also investigated incidence trends by ultraviolet B radiation (UVB) exposure levels.

METHODS: Using Surveillance, Epidemiology, and End Results (SEER) program data (1973-2009), we calculated age-adjusted incidence rates, annual percent changes, and 95% confidence intervals (CIs) for each category of interest. Incidence trends were also evaluated using joinpoint and loess regression models. SEER registries were categorized with respect to low or high UVB radiation exposure.

RESULTS: From 1973-2009, 1,230 children of white race were diagnosed with malignant melanoma. Overall, pediatric melanoma increased by an average of 2% per year (95% CI, 1.4%-2.7%). Females, 15-19 year olds, and individuals with low UVB exposure had significantly higher incidence rates than males, younger children, and those living in SEER registries categorized as high UVB. Over the study period, males experienced increased incidence rates for melanoma on the face and trunk, and females on the lower limbs and hip. The only decreased incidence trend we observed was among 15-19 year olds in the high UVB exposure group from 1985-2009. Loess curves indicated similar patterns.

CONCLUSIONS: These results may help elucidate possible risk factors for adolescent melanoma, but further individual-level studies will be necessary to determine the reasons for increasing incidence trends.

Citation Format: Jeannette Wong, Jenine Harris, Carlos Rodriguez-Galindo, Kimberly Johnson. Incidence trends of childhood and adolescent melanoma in the United States from 1973-2009. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2530. doi:10.1158/1538-7445.AM2013-2530