bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 2926: The regulatory mechanism of human LY6K related to carcinogenesis and metastasis in breast cancer
Authors: Kong Hyun Kyung , Son Da Som , Park Jong Hoon 
Published: July 2016

Abstract
The human lymphocyte antigen 6 complex locus K (LY6K) belongs to the lympocyte antigen 6/urokinase-type plasminogen activator receptor (Ly-6/uPAR) superfamily which are associated with development of the immune system and carcinogenesis. LY6K is a cancer biomarker and a therapeutic target that induces invasion and metastasis by activating the Raf-1/MEK/ERK signaling pathway and that stimulates cytotoxic T lymphocytes. However, the molecular mechanisms including genetic and epigenetic that determine human LY6K transcription are complete unknown. To elucidate the genetic mechanisms involved in human LY6K gene regulation and expression, multiple cis elements were predicted using TRANSFAC software, and the LY6K regulatory region was identified using the lucifearse assay in the human LY6K gene promoter. We performed chromatin immunoprecipitation, electrophoretic mobility shift analysis, and supershift assays to investigate the transcription factor activity on the LY6K promoter, and the effect of a single nucleotide polymorphism (SNP) and CpG site methylation on AP-1 transcription factor binding affinity. AP-1 and the CREB transcription factor bound to LY6K promoter within -550/-1, which was essential for LY6K expression but only the AP-1 heterodimer, JunD and Fra-1, modulates LY6K gene transcriptional level. A decrease in LY6K was associated with the SNP242 C allele, a polymorphic G/C-SNP at the 242 nucleotide in the LY6K promoter region (rs2585175), or methylation of the CpG site, which was closely located with the AP-1 site by interfering with binding of the AP-1 transcription factor to the LY6K promoter. In summary, AP-1 activation is important role in promoting LY6K gene expression that regulates cell mobility of breast cancer cells, whereas the SNP242 C allele or methylation of the CpG site may reduce the risk of invasion or metastasis by interfering AP-1 activation. And DNA methylation and histone modification in the 5’-flanking region of the LY6K gene plays an important role in LY6K expression in both breast cancer cells and breast cancer. An understanding of genetic and epigenetic changes in LY6K may contribute to the diagnosis of carcinogenic risk and to an enhanced prediction of outcome in patients with breast cancer.
Citation Format: Hyun Kyung Kong, Da Som Son, Jong Hoon Park. The regulatory mechanism of human LY6K related to carcinogenesis and metastasis in breast cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2926.
Abstract 2940: The p53 mutation R273H contributed to drug resistance of EGFR tyrosine kinase inhibitors
Authors: Fang Yueh-Fu , Lin Chun-Yu , Lee Peichih 
Published: July 2016

Abstract
Tyrosine kinase inhibitors (TKIs) of epidermal growth factor receptor (EGFR) were the standard first-line treatments for lung cancers with activating EGFR mutations. Emergent drug resistance is the major problem in the patients who received treatment of EGFR TKIs. Second point mutation T790M mutations could be found in 50-60% patients who had drug resistance to EGFR TKIs. Alternative pathway of Met signaling, transformation to small cell lung cancer, over-expression of other HER family receptors or epithelial mesenchymal transit were reported in these patients who had drug resistance to EGFR TKIs. NFKB pathway played a role of early resistance to EGFR TKIs in the patients.
The p53 mutation could be found in 70-80% lung adenocarcinoma patients. These mutations could be found in lung cancer patients who had wild type or mutated EGFR. Lung adenocarcinomas with mutated p53 lose tumor suppressor function of wild type p53 and have new function from mutated p53. We thought p53 mutation may have gain of function and result in drug resistance to EGFR TKIs in lung cancer patients.
We knocked down p53 in three cancer cell line, MDA-MB-468 (p53 R273H), BT-549 (p53 R249S) and H322 (p53 R248L). We found knockdown of p53 R273H in MDA-MB-468 increased sensitivity to gefitinib. Knockdown of p53 R249S and p53 R248L showed the same response to gefitinib in cancer cell lines BT-549 and H322.
Lung cancer cell line HCC827 had EGFR exon 19 deletion and was sensitive to gefitinib. We overexpressed p53 R273H, p53 R157H and p53 R249S in HCC827 lung cancer cell line. Overexpression of p53 R273H increased resistance to gefitinib in HCC827 lung cancer cell line. Overexpression of p53 R157H and p53 R249S did not increased the resistance to gefitinib.
Conclusion: Gain of function of p53 R273H increased resistance to EGFR TKIs in cancer cell lines. Further immunohistochemistry staining and gene analysis of mutated p53 will be done in lung adenocarcinoma from lung cancer patients who received EGFR TKIs.
Citation Format: Yueh-Fu Fang, Chun-Yu Lin, Peichih Lee. The p53 mutation R273H contributed to drug resistance of EGFR tyrosine kinase inhibitors. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2940.
Abstract 2946: Increased ALDH7A1 expression enhances the resistance to the anticancer drugs and colony formation in lung cancer cell lines
Authors: Sakamori Yuichi , Ozasa Hiroaki , Kunii Eiji , Yagi Yoshitaka , Tsuji Takahiro , Nomizo Takeshi , Nagai Hiroki , Kim Young Hak , Maeno Ken , Oguri Tetsuya , Mishima Michiaki 
Published: July 2016

Abstract
Background: Aldehyde dehydrogenase (ALDH) forms a superfamily of enzymes that catalyze conversion of aldehydes into carboxylic acids, and they are categorized into 19 families in human. Increased ALDH activity was reported to be a potential marker of cancer stem cell (CSC) in various solid tumors including lung cancer. Furthermore, High ALDH expression has been shown to be involved in drug resistance to conventional cytotoxic drugs. Recent studies revealed that ALDH7A1 is highly expressed in prostate cancer and associated with recurrence in patients with surgically resected non-small-cell lung cancer. However, there is not a fundamental link between ALDH7A1 expression and malignant phenotype, including drug resistance and colony formation.
Material and methods: Anticancer drug resistant cell lines were established from lung cancer cell lines (PC-6, DMS53, PC-14, PC-9, NCI-H23 and NCI-H2228 cells) by exposure to various anticancer drug, including 7-ethyl-10-hydroxycamptothesin (SN-38), gemcitabine (GEM), cisplatin (CDDP), etoposide, paclitaxel (TXL), pemetrexed, amrubicin, erlotinib and crizotinib. Protein expression was determined by western blotting and gene expression was examined by RT-PCR. ALDH enzyme activity was measured by ALDEFLOUR TM assay. Proliferation was measured using MTS assay. ALDH7A1encoding plasmid was stably transfected into PC-14 cell. These transfected cells displayed sphere formation on ultralow binding plates and survived for more than 3 weeks.
Results: We found that the levels of ALDH7A1 expression were higher in various anticancer drug-resistant lung cancer cell lines compared with the parental cells. ALDH enzyme activity was about 4-9 fold higher in SN-38, TXL, CDDP and GEM resistant cell lines (PC6/SN38, PC6/TXL, PC14/CDDP and PC14/GEM) than the parents cells. Up-regulation of ALDH7A1 expression by using a forced expression vector in PC14 cell altered cytotoxicity to SN-38 and TXL. Furthermore, overexpression of ALDH7A1in PC-14 cells enhanced sphere formation relative to the cells transfected with control vector.
Conclusion: These results suggested that increased ALDH7A1 expression in lung cancer cell lines might be one of the mechanisms of acquired resistance to anticancer agents and enhance colony formation.
Citation Format: Yuichi Sakamori, Hiroaki Ozasa, Eiji Kunii, Yoshitaka Yagi, Takahiro Tsuji, Takeshi Nomizo, Hiroki Nagai, Young Hak Kim, Ken Maeno, Tetsuya Oguri, Michiaki Mishima. Increased ALDH7A1 expression enhances the resistance to the anticancer drugs and colony formation in lung cancer cell lines. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2946.
Abstract 2954: MAP-kinase pathway activation facilitates survival of persistent FGFR1-amplified lung cancer cells upon FGFR inhibition
Authors: Malchers Florian , Ercanoglu Meryem Seda , Thomas Roman Kurt 
Published: July 2016

Abstract
One recurrent alteration of squamous cell lung cancer is the amplified region of the 8p12-p11 locus. The tyrosine kinase fibroblast growth factor receptor 1 (FGFR1) seems to be one of the most prominent targets of this amplification. Thus, small molecules inhibiting FGFRs have been employed to treat FGFR1-amplified squamous cell lung cancer. However, only about 16% of such FGFR1-amplified tumors respond to single agent inhibitor therapy. Several tumors exhibited insufficient tumor shrinkage, compatible with the existence of persistence of inhibitor-resistant tumor cells in the tumor. To investigate the mechanism of FGFR-inhibitor persistence we studied the lung cancer cell lines DMS114 and H1581. Both cell lines demonstrate GI50 values in the nanomolar range upon three different FGFR-inhibitors. However, both cell lines exhibit sustained cell viability within 0.5 to 5 μM inhibitor treatment, indicating a subpopulation of persistent cells. We therefore isolated these persistent cells by treating with a high dose of FGFR inhibitors. After 8 to 12 weeks the cells were completely resistant against all FGFR inhibitors tested. Genetic identity with the original cell line was confirmed by fingerprinting. We found that while parental cell lines showed depleted pERK signals, persistent cells were marked by a constant pERK level upon treatment. In H1581 cells, reactivation of the mitogen-activated protein kinase (MAPK) pathway was demonstrated by an active RAS-pulldown assay. Whole exome sequencing (WES) revealed high and focal NRAS amplification and DUSP6 depletion, leading to MAPK-pathway reactivation. Furthermore, retroviral overexpression of wild type RAS-isoforms induced FGFR-inhibitor resistance in parental H1581 cells. In DMS114 we observed MET and IGF-1R activation as possible mechanisms of persistence. Furthermore, co-inhibition of FGFR and MEK was a highly effective combination therapy to treat FGFR-inhibitor persistent cells. This study associates the MAPK-pathway as a key pathway for FGFR-dependent cell lines. Furthermore, these results suggest a beneficial FGFR / MEK combination treatment to avoid the outgrowth of FGFR-inhibitor persistent cells.
Citation Format: Florian Malchers, Meryem Seda Ercanoglu, Roman Kurt Thomas. MAP-kinase pathway activation facilitates survival of persistent FGFR1-amplified lung cancer cells upon FGFR inhibition. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2954.
Abstract 2955: Herceptarg, a novel heterodimeric biparatopic common light chain IgG1 antibody based on trastuzumab and pertuzumab, exerts potent anti-tumoral activity
Authors: Moessner Ekkehard , Hofer Thomas , Waldhauer Inja , Scheuer Werner , Hosse Ralf , Duerner Lydia , He Mi , Zick Karlheinz , Fischer Jens , Sustmann Claudio , Weinzierl Tina , Bacac Marina , Gerdes Christian , Umana Pablo , Klein Christian 
Published: July 2016

Abstract
Introduction: Trastuzumab and pertuzumab are humanized antibodies recognizing different functional HER2 epitopes. Preclinical data demonstrated strong anti-tumoral efficacy when combining them (Scheuer et al., Canc Res, 2009). The CLEOPATRA trial showed that the addition of pertuzumab to trastuzumab + docetaxel strongly improves overall survival of HER2+ metastatic breast cancer patients (Swain et al., NEJM, 2015). Herceptarg is a novel heterodimeric 1+1 biparatopic common light chain IgG1 antibody based on trastuzumab and pertuzumab.
Methods: Using consensus light chains, pertuzumab heavy chain affinity maturation via phage display and knob-into-holes technology, a heterodimeric biparatopic common light chain antibody based on trastuzumab and pertuzumab was generated (Figure 1A). This bispecific antibody was characterized in direct comparison to the respective parental antibodies and their combination in vitro by surface plasmon resonance, proliferation, ADCC and CDC assays and in vivo using the orthotopic KPL-4 breast cancer xenograft model. KPL-4 cells were provided by Prof. Kurebayashi (Kawasaki Medical School, Kurashiki, Japan).
Results: In vitro, Herceptarg has the highest binding affinity for HER2 on cells, mediates potent ADCC activity, comparable or superior growth inhibition activity of breast and gastric cancer cells and CDC superior to the combination of pertuzumab and trastuzumab. In vivo, Herceptarg (10 mg/kg, q1w) mediates anti-tumoral efficacy in the orthotopic KPL-4 breast cancer xenograft model resulting in tumor regression comparable to the combination of trastuzumab and pertuzumab (10 mg/kg, q1w, each), and superior to the respective single agent therapies.
Conclusions: Taken together, these data demonstrate that Herceptarg, as a single IgG1 bispecific antibody is superior (or at least comparable) to the combination of trastuzumab and pertuzumab in vitro and in vivo and may ultimately improve outcome of breast and gastric cancer patients.
Citation Format: Ekkehard Moessner, Thomas Hofer, Inja Waldhauer, Werner Scheuer, Ralf Hosse, Lydia Duerner, Mi He, Karlheinz Zick, Jens Fischer, Claudio Sustmann, Tina Weinzierl, Marina Bacac, Christian Gerdes, Pablo Umana, Christian Klein. Herceptarg, a novel heterodimeric biparatopic common light chain IgG1 antibody based on trastuzumab and pertuzumab, exerts potent anti-tumoral activity. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2955.
Abstract 2958: A cancer-specific monoclonal antibody against podocalyxin developed by CasMab technology inhibited the tumor growth by antibody-dependent cellular cytotoxicity
Authors: Kato Yukinari , Ogasawara Satoshi , Kunita Akiko , Fujii Yuki , Kaneko Mika K. 
Published: July 2016

Abstract
Background: Podocalyxin (PODXL) is a CD34-related sialomucin and a well-known marker of embryonic stem cells. PODXL is expressed in many cancers including brain tumors, breast cancers, and colorectal cancers. Overexpression of PODXL is an independent predictor of progression, metastasis, and poor outcome. In contrast, PODXL is highly expressed in normal cells such as vascular endothelial cells (VECs) or renal podocytes. Although many monoclonal antibodies (mAbs) against PODXL have been established, they bind to both cancer and normal cells. We recently established CasMab technology for developing cancer-specific mAbs, which could target only cancer cells, although those membranous proteins are highly expressed in both cancer and normal cells.
Methods: We immunized mice with human PODXL, which was overexpressed in a glioblastoma cell line. Cancer-specific mAbs were screened using flow cytometry against PODXL-expressing cancer and normal cells. The cancer specificity was confirmed using immunohistochemistry against breast cancer tissues. A mouse-human chimeric anti-PODXL mAb was produced and antibody-dependent cellular cytotoxicity (ADCC) was investigated in vitro. The in vivo efficacy of anti-PODXL mAbs was evaluated using xenograft models of PODXL-expressing cell lines.
Results: One clone of anti-PODXL mAbs, which was established by CasMab technology, reacted with PODXL-expressing many cancer cell lines including breast cancers, brain tumors, and malignant mesotheliomas, whereas it did not bind to VECs in flow cytometry. The anti-PODXL mAb reacted only with PODXL-expressing cancer cells, not with VECs in breast cancer tissues in immunohistochemistry. Furthermore, the anti-PODXL mAb possesses ADCC activity in vitro and anti-tumor effect in vivo.
Conclusion: The anti-PODXL mAb established by CasMab technology could be useful for targeting PODXL in cancer, although PODXL is highly expressed in many normal cells.
Citation Format: Yukinari Kato, Satoshi Ogasawara, Akiko Kunita, Yuki Fujii, Mika K. Kaneko. A cancer-specific monoclonal antibody against podocalyxin developed by CasMab technology inhibited the tumor growth by antibody-dependent cellular cytotoxicity. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2958.
Abstract 2960: Potent in vivo activity of site-specific indolino-benzodiazepine antibody-drug conjugates (ADCs) generated via engineered cysteine conjugation
Authors: Yoder Nicholas C. , Bai Chen , Wilhelm Alan , Maloney Erin K. , Ab Olga , Reid Emily E. , Shizuka Manami , Tavares Daniel , Laleau Rassol , Sun Xiuxia , Bogalhas Megan E. , Wang Lintao , Pinkas Jan , Miller Michael L. , Chari Ravi , Keating Thomas A. 
Published: July 2016

Abstract
ADCs are widely studied for cancer therapy, with numerous agents in preclinical and clinical development embodying a wide array of targets, linker chemistries, and cytotoxic effector classes. A fourth element of ADC design that has received much attention recently is the site of conjugation of the cytotoxic molecule to the antibody. Historically, lysine- or interchain cysteine-directed conjugation has been used, but site-specific chemistries have become increasingly popular. Our previous evaluation of site-specific and lysine-linked ADCs utilizing a tubulin-acting maytansinoid effector molecule found the lysine-linked version was more active in vivo (Yoder et al., AACR 2015 #645). Here we present a comparison of engineered cysteine site-specific and lysine-linked ADCs utilizing the previously described indolino-benzodiazepine (henceforth referred to as IGN) effector IGN-P1 (Miller et al., AACR 2015 #652) which is designed to undergo proteolytic cleavage upon cell uptake to release a potently cytotoxic DNA alkylator.
We show that HC-S442C mutants of human IgG1 can be conjugated via maleimide chemistry to IGN-P1 to give stable, potent, and homogeneous ADCs with drug to antibody ratio (DAR) of 2. The in vitro potency of engineered-cysteine IGN-P1 ADCs is largely dependent on the DAR of the ADC, although some difference is observed between HC-S442C and other cysteine mutants used for conjugation.
Pharmacokinetic study of C442 maleimide conjugates suggests that the chemical linkage between effector and antibody is stable upon administration in mice. Further, and in contrast to our previous observations utilizing maytansinoid ADCs, the site-specific and Lys-linked IGN-P1 ADCs showed comparable efficacy in vivo on a molar drug basis. This effect was observed across two different antibodies targeting two different cell surface antigens. These results suggest that, in certain cases, site-specific conjugation chemistry can offer comparable activity to heterogeneous conjugation at well-tolerated doses.
Citation Format: Nicholas C. Yoder, Chen Bai, Alan Wilhelm, Erin K. Maloney, Olga Ab, Emily E. Reid, Manami Shizuka, Daniel Tavares, Rassol Laleau, Xiuxia Sun, Megan E. Bogalhas, Lintao Wang, Jan Pinkas, Michael L. Miller, Ravi Chari, Thomas A. Keating. Potent in vivo activity of site-specific indolino-benzodiazepine antibody-drug conjugates (ADCs) generated via engineered cysteine conjugation. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2960.
Abstract 2961: deBouganin conjugated to trastuzumab overcomes multiple mechanisms of T-DM1 drug resistance
Authors: Dillon Rachelle L. , Chooniedass Shilpa , Premsukh Arjune , Adams Gregory P. , Entwistle Joycelyn , MacDonald Glen C. , Cizeau Jeannick 
Published: July 2016

Abstract
DeBouganin is a T-cell epitope-depleted variant of the type I Ribosome Inactivating Protein (RIP) plant toxin Bouganin. DeBouganin binds and deadenylates the sarcin/ricin loop of the 28S subunit of the ribosomal RNA leading to protein synthesis inhibition and apoptosis. To demonstrate the potential advantages of deBouganin over current small molecule payloads, deBouganin was randomly chemically conjugated to trastuzumab with a DAR of approximately 2 and compared to T-DM1 both in vitro and in vivo. The trastuzumab-deBouganin conjugate (T-deB) demonstrated a tighter IC50 range of killing and an overall greater potency in vitro against most cells lines with high levels of Her2 expression as compared to T-DM1. In addition, unlike T-DM1, T-deB was unaffected by inhibitors of multidrug resistance (MDR) and overexpression of Bcl-2 family members. Moreover, T-deB potency was unchanged by Her2-Her3 dimerization in the presence of heregulin. Contrary to T-DM1 which showed only minimal cytotoxicity, T-deB was highly potent in vitro against tumor cells with cancer stem cell (CSC) properties by preventing the formation of tumorspheres. Furthermore, in a BT-474 xenograft study, T-deB was more efficacious than T-DM1 resulting in increased survival of the T-deB treated mice. Overall, the results demonstrate the potency and efficacy of deBouganin and emphasize the importance of using payloads with different MOAs. The data suggest that deBouganin used alone or in combination with other payloads could be a highly effective cancer therapeutic that would provide prolonged clinical benefit.
Citation Format: Rachelle L. Dillon, Shilpa Chooniedass, Arjune Premsukh, Gregory P. Adams, Joycelyn Entwistle, Glen C. MacDonald, Jeannick Cizeau. deBouganin conjugated to trastuzumab overcomes multiple mechanisms of T-DM1 drug resistance. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2961.