bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 2583: Refinement of inhibitors of the KRAS-signaling naocluster protein, CNKSR1, that block oncogenic KRAS signaling and growth
Authors: Kirkpatrick D. Lynn , Indarte Martin , Scott Mike , Madrigal Assael , Grandjean Geoffrey , Powis Garth
Published: August 2015

Introduction: KRAS, the predominant form of mutated RAS (mut-KRAS), is found in ∼25% of patient tumors across many cancer types and plays a critical role in driving tumor growth and resistance to therapy. CNKSR1 (connector enhancer of kinase suppressor of Ras 1) a protein associated with KRAS in the RAS membrane signaling nanocluster and we have shown it is critical for mut-KRAS but not wild type (wt)-KRAS signaling and cell proliferation. CNKSR1 is a multi-domain protein with a pleckstrin homology (PH) domain, which we have exploited to discover inhibitors that selectively inhibit mut-KRAS tumor growth. The initial leads identified were found to inhibit mut-KRAS signaling and growth of mut-KRAS isogenic NSCLC cell lines (IC50 ∼ 30 μM) and compound refinement provided PHT-7390 and 7391 (IC50 5 to 10 μM). Importantly, they did not block the growth of wt-KRAS cell lines at concentrations up to 100 μM. In mice the agents had antitumor activity againsta mut-KRAS xenograft model and improved the activity of EGFR inhibitors without observable toxicity, but had poor pharmacokinetic properties.Methods: PHusis has used its in silico computational modeling of the PH-domain of CNK1 to optimize its lead inhibitors to improve potency and pharmacokinetic properties. In silico compound refinement has been paired with surface plasmon resonance spectroscopy (SPR) and in vitro cell line screening to provide the latest panel of highly potent CNK1 inhibitors that are moving toward late preclinical development.

Results: A panel of analogues of PHT-7390 and 7391 were synthesized with the aim of improving potency and pharmacokinetic properties. This structural optimization yielded several analogues with up to 100 fold greater potency than PHT-7390 to mut-KRAS NSCLC lines (IC50 10-100 nM) while retaining the differential in effect against wt-KRAS lines without activity up to 100 μM. Target engagement studies have shown that the agents inhibit mut-KRAS signaling in similar fashion as KRAS knockdown with siRNA, confirming on target effects in cells. Pharmacokinetic properties were also improved and agents have moved to clinical candidate selection. Conclusion: Potent and specific inhibitors of CNK1 PH-domain with improved pharmacokinetics have been identified. These novel PH-domain inhibitors now provide a therapeutic potential for patients with oncogenic KRAS for which there is currently no effective therapy.

Citation Format: D. Lynn Kirkpatrick, Martin Indarte, Mike Scott, Assael Madrigal, Geoffrey Grandjean, Garth Powis. Refinement of inhibitors of the KRAS-signaling naocluster protein, CNKSR1, that block oncogenic KRAS signaling and growth. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2583. doi:10.1158/1538-7445.AM2015-2583
Abstract 2599: Discovery and pharmacological characterization of the second generation of Btk inhibitors with improved target selectivity and enhanced in vivo efficacy
Authors: Zhang Jiayin , Liu Dong , Shen Ru , Yan Yinfa , Yang Liuqing , Zhang Minsheng , Feng Jun , Fu Beibei , Hu Jerry , Lu Biao , Wan Hong , Zhang Lei , Tao Weikang , Zhang Lianshan , Cao Jingsong
Published: August 2015

Bruton's tyrosine kinase (Btk) is an essential component of the B-cell receptor (BCR) signaling pathways regulating survival, activation, proliferation, and differentiation of B lymphocytes. The first Btk inhibitor, Ibrutinib, has demonstrated a significant clinical efficacy in a variety of B-cell malignancies. Through structure-guided approach, we have discovered two series of novel and potent Btk inhibitors, represented by EBI-1266 and EBI-1367, respectively. Both of these compounds showed high potency in inhibiting Btk kinase activity and growth of a number of aggressive lymphoma cell lines driven by aberrant BCR signaling, with IC50 value within low nanomolar range. Mechanistic studies examining BCR signaling pathway in related B cell lymphoma cell lines revealed that both EBI-1266 and EBI-1367 potently inhibited Btk phosphorylation and downstream Erk phosphorylation, similar to Ibrutinib. Furthermore, each compound showed unique and significant superiority over Ibrutinib: EBI-1266 had a cleaner selectivity profile against a panel of kinases with a cysteine residue in the conserved catalytic domain, and EBI-1367 exhibited >10-fold higher in vivo exposure in multiple preclinical species. In a tumor xenograft mouse model where tumor growth is dependent on Btk activity, both EBI-1266 and EBI-1367 showed significant oral anti-tumor activities, with EBI-1367 being more efficacious than Ibrutinib, consistent with a higher exposure of EBI-1367 in both blood and tumor tissues. No evidence of overt toxicities was observed in rodents with prolonged oral administration for two weeks with doses at least 3-fold above a highly efficacious dose. In summary, the pharmacological profiles of EBI-1266 and EBI-1367 indicate that these compounds have a great potential to become the next generation of Btk inhibitors, offering advantages in pharmaceutical development, enhanced in vivo efficacy and reduced toxicities. We are currently performing IND-enabling studies aiming to initiate phase I clinical trials for these Btk inhibitors.

Citation Format: Jiayin Zhang, Dong Liu, Ru Shen, Yinfa Yan, Liuqing Yang, Minsheng Zhang, Jun Feng, Beibei Fu, Jerry Hu, Biao Lu, Hong Wan, Lei Zhang, Weikang Tao, Lianshan Zhang, Jingsong Cao. Discovery and pharmacological characterization of the second generation of Btk inhibitors with improved target selectivity and enhanced in vivo efficacy. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2599. doi:10.1158/1538-7445.AM2015-2599
Abstract 2601: A natural small molecule, catechol, induces c-Myc degradation by directly targeting ERK2 in lung cancer in vitro and in vivo
Authors: Lim Do Young , Shin Seung Ho , Malakhova Margarita , Lee Mee-Hyun , Bode Ann M. , Dong Zigang
Published: August 2015

For decades, lung cancer has been a leading cause of death in the U.S., mainly due to oncogenic signaling pathways activated by carcinogens such as smoking. Various carcinogens induce EGFR/RAS/MAPK signaling that is critical in the development of lung cancer. In particular, constitutive activation of extracellular signal-regulated kinase 2 (ERK2) is observed in many lung cancer patients, and therefore developing compounds capable of targeting ERK2 against lung carcinogenesis will be beneficial to these patients. Herein, we examined the therapeutic effects of catechol (also known as pyrocatechol or 1,2-dihydroxybenzene), a naturally occurring chemical in many foods such as apple, banana, apricot, grape, plum, avocado and mushroom. Co-crystallography results suggested that ERK2 is a direct target of catechol. In agreement with the co-crystallography result, catechol was confirmed to inhibit ERK2 kinase activity in vitro. Catechol inhibited anchorage-independent KP2 and H460 lung cancer cell growth in a dose-dependent manner. Phosphorylation of c-Myc, a substrate of ERK2, was reduced in catechol-treated lung cancer cells compared to untreated controls. Decreased c-Myc phosphorylation resulted in its reduced protein stability and subsequent down-regulation of total c-Myc levels. Treatment with catechol induced G1 cell cycle arrest and resulted in a decrease of G1 phase related proteins, CDK2 and cyclin D1. In vivo study results also revealed that catechol inhibited growth of KP2 and H460 xenograft tumors. Phosphorylation levels of c-Myc were also strongly decreased by catechol treatment in vivo. Taken together, we have shown that catechol exerts inhibitory effects on the ERK2/c-Myc signaling axis in lung cancer cells to reduce tumor growth in vitro and in vivo. These findings suggest that catechol, a natural small molecule, possesses potential as a novel therapeutic agent against lung carcinogenesis.

Citation Format: Do Young Lim, Seung Ho Shin, Margarita Malakhova, Mee-Hyun Lee, Ann M. Bode, Zigang Dong. A natural small molecule, catechol, induces c-Myc degradation by directly targeting ERK2 in lung cancer in vitro and in vivo. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2601. doi:10.1158/1538-7445.AM2015-2601
Abstract 2604: Preclinical anti-tumor efficacy and mode of action of a novel, orally available, selective MKNK1 inhibitor [BAY 1143269]
Authors: Santag Susann , Siegel Franziska , Wegner Antje Margret , Schneider Claudia , Boemer Ulf , Eis Knut , Puehler Florian , Michels Martin , von Nussbaum Franz , Ziegelbauer Karl , Mumberg Dominik , Petersen Kirstin
Published: August 2015

MKNK1 (MAP kinase-interacting serine/threonine-protein kinase, also known as Mnk1) is activated by the mitogen-activated protein kinases ERK1/2 and p38. Thus, MKNK1 signaling is involved in the cellular response to environmental stress factors and cytokines. Of particular interest, MKNK1 kinase was shown to regulate mRNA translation by phosphorylating the translation initiation factor eIF4E (eukaryotic translation initiation factor 4E), known to be critical for malignant transformation but dispensable for translation in normal cells. In addition, MKNK is involved in resistance mechanisms to cancer therapeutics. Thus, the inhibition of MKNK1 activity may provide an innovative approach for anti-cancer therapy.

BAY 1143269 was identified as a potent and selective inhibitor of MKNK1 activity with an unprecedented mode of action.

It inhibits the phosphorylation of eIF4E in various cancer cell lines in vitro and leads to reduced expression of MKNK-regulated translational downstream targets, including survivin, Cdc25C and cyclin B1. In addition, BAY 1143269 potently inhibits cytokine release in LPS stimulated human blood.

In vivo, BAY 1143269 shows a significant monotherapy efficacy in non-small cell lung cancer (NSCLC), colorectal cancer and melanoma xenograft models after an once daily, oral application of 200 mg/kg in mice and 70 mg/kg in rats.

Furthermore, combination treatment with chemotherapy and BAY 1143269 gives additive efficacy in several NSCLC cell lines and patient-derived xenograft models leading to partial response (Lu7558, A549), stable disease (Lu7187, Lu7166) or significant delay in tumor re-growth versus chemotherapy alone after stop of treatment (Lu7558).

In summary, BAY 1143269 is a selective, orally available MKNK1 inhibitor that demonstrates preclinical in vivo efficacy in mono- and combination therapy and may provide therapeutic benefit for patients with solid tumors.

Citation Format: Susann Santag, Franziska Siegel, Antje Margret Wegner, Claudia Schneider, Ulf Boemer, Knut Eis, Florian Puehler, Martin Michels, Franz von Nussbaum, Karl Ziegelbauer, Dominik Mumberg, Kirstin Petersen. Preclinical anti-tumor efficacy and mode of action of a novel, orally available, selective MKNK1 inhibitor [BAY 1143269]. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2604. doi:10.1158/1538-7445.AM2015-2604
Abstract 2606: Antitumor activity of the selective RAF inhibitor HM95573 in melanoma
Authors: Bae InHwan , Ahn YoungGil , GwangMo Namgoong , Kim SuHyeon , Song JiYeon , Song TaeHun , Lee JaeHo , Lee KyuHang , Lee Young-Mi , Kim YoungHoon , Suh KweeHyun
Published: August 2015

The mitogen-activated protein kinase (MAPK) pathway is particularly important for the survival and proliferation of tumor cells. Activation of the MAPK pathway due to mutations in BRAF and NRAS is considered one of the causes of melanoma.

HM95573 is a novel, highly potent RAF kinase inhibitor. Biochemically assayed for over 120 kinases, HM95573 showed the high selectivity toward BRAF mutant and CRAF kinases. The half maximal inhibition concentrations (IC50) of HM95573 against BRAFWT, BRAFV600E and CRAF kinases were 41nM, 7nM and 2nM, respectively. The strongly inhibited kinases subsequent to RAF kinases appeared to be CSF1R (44nM), DDR1 (77nM) and DDR2 (182 nM).

HM95573 potently inhibited the growth of mutant BRAF melanoma cell lines such asA375 (IC50: 57nM) and SK-MEL-28 (69nM) and of mutant NRAS melanoma cell lines such asSK-MEL-2 (53nM) and SK-MEL-30 (24nM). In addition, the phosphorylations of MEK and ERK downstream kinases associated with cell proliferation were effectively inhibited with treatment of HM95573in mutant BRAF and mutant NRAS melanoma cells.HM95573inhibited the downstream signaling in melanoma cells even in the presence of HGF which is known to mediate innate resistance to RAF inhibitors.

HM95573 showed the excellent antitumor activity in mouse models xenografted with both of BRAF mutation cell lines (e.g. A375 and SK-MEL-28) and NRAS mutation cell lines (such as SK-MEL-2 and SK-MEL-30) compared to two RAF inhibitors approved in melanoma which were effective to only BRAF mutation cell lines under conditions tested. Furthermore, HM95573 did not show a potential to paradoxical activation inducing tumor growth in mouse xenograft study using A431 cuSCC (cutaneous squamous cell carcinoma)cancer cell.

Now, HM95573 is currently in phase I development in patients with advanced solid tumors including melanoma in Korea.

Citation Format: InHwan Bae, YoungGil Ahn, Namgoong GwangMo, SuHyeon Kim, JiYeon Song, TaeHun Song, JaeHo Lee, KyuHang Lee, Young-Mi Lee, YoungHoon Kim, KweeHyun Suh. Antitumor activity of the selective RAF inhibitor HM95573 in melanoma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2606. doi:10.1158/1538-7445.AM2015-2606
Abstract 2621: Preclinical systemic toxicity evaluation of chitosan-solid lipid nanoparticles encapsulated aspirin, curcumin and free sulforaphane (ACS) combinations in BALB/c mice
Authors: Thakkar Arvind , Chenreddy Sushma , Wang Jeffrey , Prabhu Sunil
Published: August 2015

The present study aims to evaluate the preclinical systemic toxicity profile of chitosan-solid lipid nanoparticles (c-SLNs) encapsulated aspirin (ASP), curcumin (CUR), and free sulforaphane (SFN) combination (ACS) in BALB/c mice. Recently, we demonstrated pancreatic cancer chemopreventive efficacy using ACS-SLNs delivery system in the BOP carcinogen induced pancreatic cancer hamster model. In order to develop safe ACS c-SLNs for clinical applications, it is vital to investigate their toxicity. Thus, we performed acute 3-day, sub-acute 28-day and sub-chronic 90-day toxicity studies of ACS c-SLNs in the BALB/c mice model. The mice were orally gavaged once every 24h with 200 μl ACS c-SLNs at three concentrations: low dose ACS (2+4.5+0.16 mg/kg; 1/30th of high dose), medium dose ACS (20+45+1.6 mg/kg; 1/3rd of high dose) and high dose ACS (60+135+4.8 mg/kg). Total of 60 mice were used for this study (4 mice each group X 3 timepoints X 5 groups). A standard evaluation was performed, which included daily clinical signs, weekly body weight, end-of-study blood hematology, blood clinical chemistry, gross necropsy on all animals and hematoxylin and eosin-stained examination of range of tissues from each animal. The clinical chemistry tests include blood urea nitrogen (BUN) and creatine (CRE), which indicate renal toxicity. Alanine transaminase (ALT) and alkaline phosphatase (ALP) levels indicate hepatic toxicity, while glucose (GLU) and total protein are measures of healthy growth. At the end-of-study, data revealed that mean body weight gain was consistent with low-, medium- and high-ACS c-SLN dose during acute, sub-acute and sub-chronic treatment period. The blood count and blood chemistry profiles revealed lack of systemic toxicity as the numbers were within normal ranges. Extensive histopathological examination of liver, kidney, heart, brain and pancreatic tissues showed no increase in treatment-related microscopic lesions in any of the three ACS c-SLN dose groups. Collectively, these findings demonstrate that repetitive oral administration of ACS c-SLN even at high concentrations was not associated with local or systemic toxicity and did not adversely affect the blood clinical chemistry of mice. Hence, long-term ACS c-SLN oral therapy is deemed safe for prevention of pancreatic cancer.

Citation Format: Arvind Thakkar, Sushma Chenreddy, Jeffrey Wang, Sunil Prabhu. Preclinical systemic toxicity evaluation of chitosan-solid lipid nanoparticles encapsulated aspirin, curcumin and free sulforaphane (ACS) combinations in BALB/c mice. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2621. doi:10.1158/1538-7445.AM2015-2621
Abstract 2624: Pre-clinical studies of a mutant p53 reactivating drug in pancreatic cancer
Authors: Yu Xin , Tsang Ashley T. , Li Zhe , Eng Oliver S. , Lin Hongxia , Gounder Murugesan , Carpizo Darren R.
Published: August 2015

Pancreatic cancer therapy suffers from a lack of effective chemotherapy. TP53 is second only to Kras as the most commonly mutated gene in pancreatic cancer with point mutations occurring in 75% of patients. Recently, our laboratory identified ZMC1 as an allele specific p53 mutant reactivating compound. This compound selectively kills cancer cells that express the p53-R175H mutation by restoring wildtype structure and function to this mutant. It does not reactivate the DNA contact mutant, p53-R273H or p53-R248H. This established ZMC1 as a lead compound for mutant p53 targeted drug development. We are currently investigating the potential of ZMC1 as novel anti-cancer drug through pre-clinical studies in pancreatic cancer. Previously we reported the ZMC1 allele specificity in murine pancreatic cancer cell lines derived from the KPC mouse model expressing mutant KrasG12D and different alleles of TP53 (WT, null, p53R172H, p53R270H). We have investigated the pharmacokinetics (PK) and pharmacodynamics (PD) of ZMC1 in the KPC mouse model. Using LC/MS/MS we developed a sensitive assay for detection of ZMC1 in mouse plasma. We measured drug concentrations in mouse plasma and tumor tissues in different delivery routes and different dosages in the PK studies. We have developed a PD assay for ZMC1 with cleaved caspase-3 immunostaining with which we have tested several doses of ZMC1 and found that we detect activity of ZMC1 in KPCp53-R172H xenograft tumors while at the same time relatively no activity in KPCp53-R270H tumors. These same assays were also performed on KPC autochthanous tumors and again revealed activity of ZMC1 in the KPCp53-R172H mice. Efficacy studies in the KPCp53-R172H xenografts showed potent tumor growth inhibition at both intravenous (1mg/kg) and intraperitoneal (5mg/kg) dosing while no evidence of growth inhibition in KPCp53-R270H. Furthermore, ZMC1 extended the survival days from average 15 days to 26 days in the KPCp53-R172H mice but it was not significantly observed in the KPCp53-R270H mice. The tumor growth rate was also decreased in the KPCp53-R172H but not in the KPCp53-R270H mice. These studies indicated that ZMC1 is an allele-specific p53 mutant reactivating compound and holds promise for future applications in pancreatic cancer.

Citation Format: Xin Yu, Ashley T. Tsang, Zhe Li, Oliver S. Eng, Hongxia Lin, Murugesan Gounder, Darren R. Carpizo. Pre-clinical studies of a mutant p53 reactivating drug in pancreatic cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2624. doi:10.1158/1538-7445.AM2015-2624
Abstract 2655: Determinants of sensitivity to PI3K inhibitors in PIK3CA wildtype gastric tumor cells
Authors: Chong Mei Ling , Bhattacharya Bhaskar , Voon Dominic , Koh King Xin , Low Hong Hui , Chang Ti Ling , Wu Mengchu , Tan Patrick Boon Ooi , Loh Marie Chiew Shia , Benoukraf Touati , Hung Huynh The , Politz Oliver , Liu Ningshu , Soong Richie Chuan Teck
Published: August 2015

Background: PIK3CA mutations are emerging as useful indicators of sensitivity to PI3K inhibitors, However many PIK3CA wildtype cells are also sensitive to PI3K inhibitors, and a biomarker of these cells is desirable This study aimed to identify and functionally verify determinants of sensitivity to PI3K inhibitors in PIK3CA wildtype cells.

Materials and Methods: Eight PIK3CA wildtype gastric cancer cell lines were screened by MTS assay for their sensitivity to 6 PI3K inhibitors (BAY 806946 (Copanlisib), BAY 1082439, GDC-0941, BKM120, BYL719, XL147). Categorization of cells was performed by unsupervised clustering of quantile normalized IC50 values. RNA sequencing was performed using the ScriptSeqv2 mRNA-Seq kit, Illumina HiSeq 2000, and Partek software. Functional evaluation was performed by lentivirus modulation and standard phenotypic analyses. Six patient-derived PIK3CA wildtype gastric tumor xenograft models (PDXs) were also evaluated for sensitivity to PI3K inhibition and candidate expression.

Results: Unsupervised clustering revealed two subgroups, comprising 3 resistant and 5 sensitive cell lines. Among differentially expressed genes, IGFBP3 had the highest overexpression (67-fold) in sensitive cells. IGFBP3 encodes insulin growth factor binding protein 3, which sequesters insulin growth factor (IGF) from binding to its receptor (IGF-1R). The sequestration of IGF by IGFBP3 may repress alternative activation of PI3K pathways through IGF signaling. Consistent with this, overexpression of IGFBP3 increased cell sensitivity to PI3K inhibitors and was accompanied by reduced IGF-1R, Akt and S6 phosphorylation and increased G1 arrest. IGFBP3 expression was also significantly higher in PDXs responsive to PI3K inhibitors than in those resistant.

Conclusions: High IGFBP3 may be a useful biomarker of sensitivity to PI3K inhibitors in PIK3CA wildtype gastric tumor cells.

Citation Format: Mei Ling Chong, Bhaskar Bhattacharya, Dominic Voon, King Xin Koh, Hong Hui Low, Ti Ling Chang, Mengchu Wu, Patrick Boon Ooi Tan, Marie Chiew Shia Loh, Touati Benoukraf, Huynh The Hung, Oliver Politz, Ningshu Liu, Richie Chuan Teck Soong. Determinants of sensitivity to PI3K inhibitors in PIK3CA wildtype gastric tumor cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2655. doi:10.1158/1538-7445.AM2015-2655
Abstract 2699: Targeting GSK-3: a novel approach to enhance glioblastoma chemosensitivity
Authors: Ugolkov Andrey , Dubrovskyi Oleksii , Gaisina Irina , Yemelyanov Alex , Bondarenko Gennadiy , James Charles , Chandler James , O'Halloran Thomas , Kozikowski Alan , Raizer Jeffry , Mazar Andrew
Published: August 2015

Glioblastoma (GBM) is, in essence, an incurable cancer, with most patients surviving 12-15 months following initial diagnosis. Previously published studies identified Glycogen Synthase Kinase-3 (GSK-3) as a new therapeutic target in GBM. Because GSK-3beta is a positive regulator of NF-kappaB-mediated survival and chemoresistance in cancer cells, we hypothesize that the inhibition of GSK-3 may overcome NF-kappaB-mediated chemoresistance to conventional drugs in human GBM. Using IVIS imaging of live mice, we found that: 1) NF-kappaB is constitutively active in orthotopic GBM patient-derived xenograft (PDX) tumors expressing an NF-kappa luciferase reporter; and 2) a single intravenous injection of our novel GSK-3 inhibitor 9-ING-41 (25 mg/kg) significantly reduced NF-kappaB transcriptional activity in orthotopic GBM PDX. Using 3 different orthotopic GBM PDX- tumor models, enabled for bioluminescence imaging through luciferase modification, we evaluated antitumor effects of 9-ING-41, alone as well as in combination with irinotecan, CCNU and temozolomide. Our in vivo results revealed that treatment with a combination of 9-ING-41 and irinotecan delays GBM PDX tumor growth, relative to either agent as a monotherapy, and, even more promising, 9-ING-41+CCNU leads to a complete tumor regression. Histological evaluation of mouse brain confirmed the absence of cancer cells and a formation of cyst at the location of intracranial tumor in mice treated with 9-ING-41+CCNU. Our results provide a rationale to advance 9-ING-41 for clinical evaluation in treating GBM, especially when combined with CCNU cytotoxic therapy.

Citation Format: Andrey Ugolkov, Oleksii Dubrovskyi, Irina Gaisina, Alex Yemelyanov, Gennadiy Bondarenko, Charles James, James Chandler, Thomas O'Halloran, Alan Kozikowski, Jeffry Raizer, Andrew Mazar. Targeting GSK-3: a novel approach to enhance glioblastoma chemosensitivity. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2699. doi:10.1158/1538-7445.AM2015-2699
Abstract 271: Targeting PD-1, TIM-3 and LAG-3 in combination for improved immunotherapy combinations
Authors: Kehry Marilyn , Horlick Robert , Bowers Peter , Jun Toni , da Silva Correia Jean , Graves Jonathan , Wang Yan , Laken Haley , King David J.
Published: August 2015

Antibodies that inhibit the CTLA-4 and PD-1 checkpoint pathways have shown significant activity as either single agents or in combination in both mouse models and clinical studies. TIM-3 and LAG-3 have been reported to function as additional immune checkpoints which limit anti-tumor T cell responses and represent an opportunity for additional combination approaches to improve patient response to immunotherapy. To explore the potential for targeting other immune checkpoints in combination with anti-PD-1, studies were conducted in syngeneic mouse models and in human in vitro assays.

A series of surrogate mouse specific reagents targeting TIM-3, LAG-3 and PD-1 have been generated to improve understanding of combination checkpoint therapy in several syngeneic models. Mouse tumor models were characterized by IHC and FACS for relevant markers including PD-L1, Foxp3, TIM3and LAG3, to identify those most likely to be subject to immunosuppressive mechanisms contributing to tumor growth and immune evasion. Initial syngeneic studies in MC38 and Colon 26 demonstrated that combinations of antibodies to murine PD-1, TIM-3 and LAG-3 improved efficacy over single agent therapy, suggesting that combinations of these checkpoint inhibitors might have therapeutic potential in the clinic. The results of ongoing studies to evaluate the dose response of the combinations as well as the contribution of the antibody isotype will be reported.

Potent anti-human PD-1, -TIM-3 and LAG-3 clinical candidates have been identified using SHM-XEL™, which combines mammalian cell display of human IgG with somatic hypermutation in vitro to select and mature antibodies with desired biological activities. In a DC/T cell MLR assay, combination of the anti-LAG-3 antibody with a novel anti-PD-1 antibody could further increase T cell secretion of IL-2 up to 30-fold compared to anti-LAG-3 alone. Anti-TIM-3 in combination with anti-PD-1 also improved the EC50 up to 6-fold. Staining of activated purified CD4+ or CD8+ T-cells demonstrate that co-expression of PD-1 and LAG-3 increases upon activation compared to naïve T-cells, suggesting combination therapy may be particularly effective against activated or exhausted T-cells. These in vitro data and in vivo pre-clinical model results support evaluating combination immunotherapy with anti-LAG-3, anti-TIM-3, and anti-PD-1 in cancer patients.

Citation Format: Marilyn Kehry, Robert Horlick, Peter Bowers, Toni Jun, Jean da Silva Correia, Jonathan Graves, Yan Wang, Haley Laken, David J. King. Targeting PD-1, TIM-3 and LAG-3 in combination for improved immunotherapy combinations. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 271. doi:10.1158/1538-7445.AM2015-271
Abstract 2713: Stem cell mutagenesis and carcinogenesis in the colon of wild type and immune compromised mice
Authors: Gold Barry , Whetstone Ryan
Published: August 2015

To test the hypothesis that a role of inflammation in the etiology of cancer is associated with the production of RONS and subsequent DNA damage, we determined the mutation frequency (MF) in colonic stem cells in C57Bl/6 mice exposed to dextran sulfate sodium (DSS), an inflammatory agent that is used in combination with azoxymethane (AOM) to produce colon tumors in mice. AOM produces promutagenic O6-methylguanine lesions in DNA but does not induce colon tumors in C57Bl/6 mice as a single agent. The MF's in the untreated and DSS treated WT and TCRβ-/- mice were <10-5 indicating that DSS and subsequent inflammation does not generate stem cell mutations in mice that are WT for DNA repair. AOM yielded mutant crypts in WT and TCRβ-/- mice with MF's of ∼4×10-4 and 2×10-4, respectively, which represents a statistically significance decrease in the MF in the immune compromised mice. These results suggest enhanced survival of AOM damaged stem cells in WT vs. TCRβ-/- mice. The combined treatment of AOM+DSS afforded fully mutated crypts in both strains but with a lower MF than observed with AOM alone indicating that DSS induced inflammation destroyed pre-existing AOM mutated crypts. Using the MF in WT mice, the efficiency for the conversion of an O6-methylguanine lesion into a stem cell mutation was estimated to be 0.03%. The carcinogenicity of AOM and/or DSS was evaluated in WT, TCRβ-/-, TCRδ-/- and TCRβ-/-TCRδ-/- mice. At lower DSS exposure (1.5%), there was a significant reduction in tumor incidence, multiplicity and tumor progression in the TCRβ-/- and TCRβ-/-TCRδ-/- vs. WT B6 mice. However, at higher DSS concentration (2%) the difference between the mouse strains disappeared because of an increase in the TCR null mice without a concomitant increase in the WT mice.

Citation Format: Barry Gold, Ryan Whetstone. Stem cell mutagenesis and carcinogenesis in the colon of wild type and immune compromised mice. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2713. doi:10.1158/1538-7445.AM2015-2713
Abstract 2716: Epstein-Barr virus-encoded BARF1 downregulates SMAD4 and increases miR-146a in gastric carcinoma cells
Authors: Kim Dong Ha , Yoon Chan Jin , Rho Jin Kyung , Middeldorp Jaap M. , Woo Jun Hee , Chang Mee Soo
Published: August 2015

Recently, molecular analytic data from ‘The Cancer Genome Atlas’ (TCGA) (http://www.cbioportal.org) has re-confirmed that Epstein-Barr virus (EBV)-infected gastric carcinoma is a specialized subset of gastric carcinomas. However, viral oncogene has not yet been established in gastric carcinomas. Several reports have suggested that EBV-encoded BARF1 may be a putative viral oncogene in gastric carcinoma. The aim of this study was to investigate alterations of cellular microRNA and cellular protein by BARF1 in gastric carcinoma cells. We cloned BARF1 from naturally EBV-infected gastric carcinoma cell line, and transfected BARF1 into EBV-negative gastric carcinoma cells, thus produced a stable cell line of BARF1-transfected gastric carcinoma cells. BARF1-transfected gastric carcinoma cells revealed significantly increased cellular proliferation than its original cells. The MicroRNA array (Agilent release 16.0) data and Taqman RT-PCR results showed that cellular miR-146a was highly expressed in BARF1-transfected gastric carcinoma cells, comparing to that in original cells. In BARF1-transfected gastric carcinoma cells, transfection with BARF1-siRNA offset the increment effect of miR-146. Using bioinformatics analyses for miR-146a target (RNA hybrid 2.2 and TargetScan 5.2 sites), we found that miR-146a target seed sequence existed in the 3′ UTR of SMAD4 mRNA. The Western blot assay demonstrated that SMAD4 was remarkably reduced by BARF1 transfection. When immunohistochemistry for SMAD4 was performed on 343 cases of surgically resected, human gastric carcinoma tissues, 32 (9%) EBV-infected gastric carcinoma group disclosed more frequent loss of SMAD4 than EBV-negative group. In conclusion, EBV-encoded BARF1 could promote proliferation of gastric carcinoma cells, thereby contributing to EBV-induced cancer progression, in which SMAD4 downregulation, probably through miR-146a increase, may be entailed.

Citation Format: Dong Ha Kim, Chan Jin Yoon, Jin, Kyung Rho, Jaap M. Middeldorp, Jun Hee Woo, Mee Soo Chang. Epstein-Barr virus-encoded BARF1 downregulates SMAD4 and increases miR-146a in gastric carcinoma cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2716. doi:10.1158/1538-7445.AM2015-2716
Abstract 2729: Chronic stress promotes lung cancer development via IGF-1R pathway
Authors: Jang Hyun-Ji , Boo Hye-Jin , Jung Yujin , Min Hye-Young , Lee Ho-Young
Published: August 2015

Lung cancer is a leading cause of cancer death worldwide. Although smoking is a main cause, approximately 25% of lung cancer cases are not attributable to tobacco use. Epidemiological studies strongly suggest that chronic stress influences cancer development and progression. Recent mechanistic studies showed that biological signaling pathways could contribute to such effects. But the underlying mechanisms for the association between chronic stress and lung cancer development are poorly understood. The purpose of this study is to investigate whether chronic stress can induce lung cancer development and, if so, what is the mechanism underlying the chronic stress-induced lung cancer development. We observed that stress hormone, norepinephrine (NE) increased cell viability in the absence of growth factors, foci formation, and colony formation in human bronchial epithelial cells and activated the type 1 insulin-like growth factor receptor (IGF-1R) pathway. We found that chronic stress resulted in high levels of NE in serum, activation of IGF-1R in lung tissue and promoted urethane-induced lung tumor formation in vivo. Moreover, inhibition of the IGF-1R pathway suppressed NE-induced transformed phenotypes in vitro. We further confirmed that chronic stress-induced lung tumor formation was greater in mice carrying lung-specific human IGF-1R transgene (Tg) than in wild type mice. Our results indicate that chronic stress may promote lung cancer development via the IGF-1R pathway, suggesting that IGF-1R is an effective target for the chemoprevention of stress-induced lung cancer.

Citation Format: Hyun-Ji Jang, Hye-Jin Boo, Yujin Jung, Hye-Young Min, Ho-Young Lee. Chronic stress promotes lung cancer development via IGF-1R pathway. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2729. doi:10.1158/1538-7445.AM2015-2729
Abstract 2738: Mechanisms of cadmium carcinogenesis
Authors: Nath Raghu G. , Sonawane BR , Vulimiri SV , Lin YS
Published: August 2015

Cadmium is a transition metal and an ubiquitous environmental and industrial pollutant. Laboratory animal studies and epidemiological studies have shown that exposure to cadmium is associated with various organ toxicities and carcinogenic effects. Several national and international regulatory agencies have classified cadmium compounds as carcinogenic to humans. In 2012, International Agency for Research on Cancer (IARC) reviewed the relevant information on cadmium exposure and concluded that there is sufficient evidence in humans for the carcinogenicity of cadmium and its compounds. However, the underlying molecular mechanism(s), especially for the carcinogenicity, are unknown. The mechanisms proposed for carcinogenicity include aberrant gene expression, induction of oxidative DNA damage, stimulation of cell proliferation, malignant cell transformation, inhibition of DNA damage repair, inhibition of apoptosis and epigenetic mechanisms including alteration of DNA methylation. Studies have shown that due to the slow elimination, cadmium is a cumulative toxicant and past exposures could result in toxic effect of the residual metal. To better understand the mechanisms of cadmium carcinogenicity we have reviewed in vitro experimental and in vivo animal studies focused on the proposed mechanisms of carcinogenicity as well as epidemiological evidence on carcinogenicity in lung and kidney following cadmium exposure.

Disclaimer: The views expressed are those of the authors and do not necessarily represent the views and/or policies of the U.S. EPA

Citation Format: Raghu G. Nath, BR Sonawane, SV Vulimiri, YS Lin. Mechanisms of cadmium carcinogenesis. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2738. doi:10.1158/1538-7445.AM2015-2738
Abstract 2740: Familial Hodgkin lymphoma by relationship, sex, age and histology: a joint study from five Nordic countries
Authors: Fallah Mahdi , Kharazmi Elham , Pukkala Eero , Olsen Jørgen H. , Tryggvadottir Laufey , Sundquist Kristina , Tretli Steinar , Hemminki Kari
Published: August 2015

Background: We aimed to estimate lifetime (0-79 years) cumulative risk (CR) of Hodgkin lymphoma (HL) in relatives of patients with HL by relationship, sex, age and histology.

Design: A population-based cohort of 57,475 first-degree relatives of 13,922 HL patients diagnosed in 1955-2009 in Nordic countries was followed for cancer incidence. Standardized incidence ratios (SIRs) were calculated using histology-, age-, sex-, period-, and country-specific incidence rates as the reference.

Results: The overall CR of HL in first-degree relatives of a patient with Hodgkin lymphoma was 0.6%, which represents 3-fold (SIR = 3.3, 95%CI = 2.8-3.9) increase over the general population risk (men 0.3%; women 0.2%). Significantly high CR (1%) was found among sisters with early-onset HL and unlike-sex siblings with HL diagnosed at age 30-59. The familial risk in sisters (9-fold) was higher than in brothers (4.5-fold) or unlike-sex siblings (6-fold). In general, the risk in siblings (6-fold) was higher than in parents/children (2-fold). Very high risk of HL was found for few men with two HL first-degree relatives (3-8%) and for twin brothers (18%). For the first time we found high familial risk of concordant histological subtypes of HL [lymphocyte-rich (81-fold, n = 6) and nodular sclerosis (4.6-fold, n = 22)] and also discordant subtypes.

Conclusions: Lymphocytic-rich histology type of HL showed highest familial risk. The absolute risk of familial HL was generally less than 1.5%, except for men with multiple affected first-degree relatives (3-8%), twin brothers (18%), or brothers with early-onset HL (2%).

Citation Format: Mahdi Fallah, Elham Kharazmi, Eero Pukkala, Jørgen H. Olsen, Laufey Tryggvadottir, Kristina Sundquist, Steinar Tretli, Kari Hemminki. Familial Hodgkin lymphoma by relationship, sex, age and histology: a joint study from five Nordic countries. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2740. doi:10.1158/1538-7445.AM2015-2740
Abstract 2741: The risk of cancer among children with birth defects
Authors: Lupo Philip J. , Scheurer Michael E. , Plon Sharon E. , Spector Logan E. , Mueller Beth A.
Published: August 2015

Background: Although a few genetic syndromes are known to increase cancer risk in children, the presence of a structural birth defect in the absence of these syndromes is increasingly being recognized as a risk factor for childhood cancer. To better understand associations of specific defects and cancer types, we conducted a population-based assessment to avoid biases often present in studies relying on single clinics, referral centers, or treatment networks.

Methods: Records of those diagnosed with cancer <20 years of age between 1984 and 2013 in Washington State were linked to their birth certificates (N = 4,043). Birth records of children without cancer were selected at a ratio of 10:1 for a comparison group. Information on birth defects was obtained from birth records. Logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for: 1) having any reported defect and the risk of childhood cancer; 2) having any reported defect and the risk of specific cancer types; and 3) having a specific defect and the risk of specific cancer types. All models were adjusted for birth year.

Results: Having any birth defect was associated with a 50% increased risk of childhood cancer overall (OR 1.5, 95% CI 1.2-1.8), and specifically for leukemia (OR = 1.7, 95% CI 1.2-2.4); neuroblastoma (OR = 1.9, 95% CI 1.0-3.5); soft tissue sarcoma (OR = 2.0, 95% CI 1.2-3.5); and germ cell tumors (OR = 3.0, 95% CI 1.6-5.5). Some specific defects were associated with specific cancer types: central nervous system (CNS) tumors with CNS defects (OR>4.0); leukemia, neuroblastoma, renal tumors, and soft tissue sarcoma with gastrointestinal anomalies (ORs>9.0); renal tumors and urogenital anomalies (OR>4.0); and soft tissue sarcoma with adactyly, polydactyly, or syndactyly (OR>8.0).

Conclusions: Consistent with prior studies, structural birth defects were associated with increased cancer risk. Pooling similar data from many regions will increase power to identify specific associations in order to inform molecular studies examining possible common developmental pathways in the etiologies of birth defects and cancer, and will provide information that can be translated into screening strategies for children at high risk of developing cancer.

Funding: Cancer Prevention Research Institute of Texas RP140258 and Alex's Lemonade Stand Foundation

Citation Format: Philip J. Lupo, Michael E. Scheurer, Sharon E. Plon, Logan E. Spector, Beth A. Mueller. The risk of cancer among children with birth defects. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2741. doi:10.1158/1538-7445.AM2015-2741
Abstract 2775: Prognostic significance of triple miRNAs, miR-9, miR-221, and miR-200c in breast cancer
Authors: Cheng Chun-Wen , Yu Jyh-Cherng , Hsieh Yi-Hsien , Chen Po-Ming , Wang Hsiao-Wei , Wang Hui-Chun , Shen Chen-Yang
Published: August 2015

MicroRNAs (miRNA) mediated epithelial-mesenchymal transition have been considered as a major event in cancer aggression and accounted for cancer progression. However, clinical association between synergistic effect of deregulated expression levels of the EMT-related miRNAs, including miR-9, miR-221, and miR-200c, and breast cancer prognoses remains underestimated. Initially, tissue samples were from 184 enrolled female patients, with invasive ductal carcinoma, followed up for more than ten years. miRNA expression levels between paired laser capture microdissected tumor and non-tumor cells from the primary tumor site was analyzed by quantitative real-time PCR (qRT-PCR). Differentially expressed status of the target miRNA in tumors relative to non-tumor parts (T/N ratio) was assessed their relationship with pathological characteristics and clinical outcomes of breast cancer. While miR-9 or miR-221 showed significantly higher expression level in tumor cells compared to the non-tumor ones, miR-200c exhibited the opposite (p<0.05). Based on the ROC curve, T/N ratio of 2.80- and 1.96-fold increase for miR-9 and miR-221, whereas, 1.80-fold decrease for miR-200c as risk genotypes, respectively. According to these cutoffs, high miR-9 expression in tumors was associated with advanced tumor stages (p<0.05); significant risk associations were shown between LNM-positive tumors and miR-9 (OR = 3.12) or miR-221 (OR = 1.88) (p<0.05). A joint effect on risk elevation of tumor invasion and nodal metastasis was seen in tumors having miR-9 overexpression alongside increased miR-221 or reduced miR-200c expression (p-trend<0.05). Considering the combined effect of these three miRNAs, patients harboring greater numbers of deregulated expression levels in tumors were found to have a higher risk of poor prognoses (high-stage (p-trend = 0.003) and LNM (p-trend = 0.028)) and reduced probability of 10-year overall survival, showing hazard ratio of 2.39 (p<0001 for trend test). In conclusion, deregulated levels of miR-9, miR-221, and miR-200c, may serve as prognostic biomarkers to predict disease progression and shorter OS in breast cancer.

Citation Format: Chun-Wen Cheng, Jyh-Cherng Yu, Yi-Hsien Hsieh, Po-Ming Chen, Hsiao-Wei Wang, Hui-Chun Wang, Chen-Yang Shen. Prognostic significance of triple miRNAs, miR-9, miR-221, and miR-200c in breast cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2775. doi:10.1158/1538-7445.AM2015-2775