bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 2520: FGFR2 and miR-671-5p as key participants involved in the progression of human esophageal squamous cell carcinoma
Authors: Chen Xiaojia , Li Xiaoyan , Tian Baoqing , Tan Xuan , Han Wei , Wang Jiakang , Hong An
Published: August 2018

Esophageal cancer is the world's tenth common malignant tumor. Esophageal cancer is divided into esophageal squamous cell carcinoma (ESCC) and esophageal adenocarcinoma (ECA). ESCC is the dominant histological subtype. The overall 5-year survival rate for people with advanced-stage of ESCC is only about 10%-20%, but ESCC is still not well-studied. Therefore, it is very important to study the mechanism of cancer progression in ESCC in order to develop new therapies for this deadly disease.

Fibroblast growth factor receptor2 (FGFR2) is one of the RTK members and generally regarded as an oncogene, but little is known about its function in ESCC. In our study, we proved FGFR2 played the key role in ESCC progression. From In vitro studies, overexpression of FGFR2 promoted the ESCC cells' migration, invasion, and proliferation, which was confirmed through knocking down FGFR2 in ESCC cells. In vivo xenograft tumor mouse model studies showed the tumor size from ESCC cells with FGFR2 over-expression larger than that of the control group. Conversely, the tumor size from ESCC cells with FGFR2 knock-down was significantly smaller compared with the control group. Molecular mechanism studies showed that overexpression of FGFR2 activated the ERK and AKT signal pathways and altered the cell cycle in ESCC.

In addition, decreased expression of miR-671-5p was identified by microRNA array and QPCR verify assay in ESCC–FGFR2+ tissue. Using a dual influence report system, we confirmed miR-671-5p could regulate expression of FGFR2. It was also found that FGFR2 was highly expressed whereas miR-671-5p was expressed at a low level in most of the FGFR2-positive ESCC clinic samples. Furthermore, we demonstrated that miR-671-5p could inhibit the proliferation and metastasis of ESCC cells in vitro and it could suppress growth of ESCC in vivo. The miR-671-5p suppressed MAPK and PI3K signal pathways through down-regulation of phosphorylation of FGFR2. Therefore, miR-671-5p was seen as a tumor suppressor in ESCC.

Our results demonstrated that FGFR2 and miR-671-5p are potential therapeutic targets in ESCC. They both participate in the progression of ESCC, but also play the contrasting roles. Antagonists of FGFR2 or activators of miR-671-5p could be therapeutics against ESCC.

Citation Format: Xiaojia Chen, Xiaoyan Li, Baoqing Tian, Xuan Tan, Wei Han, Jiakang Wang, An Hong. FGFR2 and miR-671-5p as key participants involved in the progression of human esophageal squamous cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2520.
Abstract 253: Gnetin C as a candidate for targeted chemopreventive and therapeutic measures in prostate cancer
Authors: Kolhatkar Urvi , Dholakia Kshiti , Sikorska Gabriela , Kumar Avinash , Martinez Luis A. , Levenson Anait S.
Published: August 2018

Overexpression of chromatin modifier protein, metastasis-associated protein 1 (MTA1) in prostate cancer contributes to tumor aggressiveness and metastasis. MTA1 ChiP-Seq analysis identified downstream targets that are transcriptionally regulated by MTA1 and suggested a link between MTA1 and ETS2. The effects of ETS2 in cancer are context-dependent and both oncogenic and tumor suppressive functions have been described. We have shown that there is a positive correlation between MTA1 and ETS2 using loss of function studies and various preclinical models of prostate cancer. Our conclusion that MTA1 functions as a co-activator for regulating ETS2 expression in prostate cancer leading to promotion of prostate cancer progression, prompted us to look for pharmacological inhibitors of MTA1/ETS2 axis. In our previous studies, we reported inhibition of MTA1 by resveratrol and its potent analog pterostilbene in vitro and in vivo. We have demonstrated that pterostilbene treatment blocks the progression of PIN and adenocarcinoma in xenografts and transgenic mouse models by inhibiting MTA1 expression and signaling. Here, we found that Gnetin C, double-resveratrol, has more potent inhibition of MTA1/ETS2 axis than other stilbenes. Gnetin C, a resveratrol dimer, is found abundantly in melinjo plant widely cultivated in Southeast Asia; its seeds and fruits are common ingredients in Indonesian culinary. As resveratrol and pterostilbene, Gnetin C has been reported to possess anti-inflammatory and anticancer activity, however it has not been considered as chemopreventive agent in prostate cancer. Using two prostate cancer cell lines, namely DU145 and PC3M cells, we found that Gnetin C shows significant inhibitory effect on cell proliferation, more potent effects in colony formation and wound healing assays than resveratrol or pterostilbene. Importantly, Gnetin C specifically and strongly downregulates MTA1 and ETS2 expression in prostate cancer cells. Taken together, our findings implicate the potential of Gnetin C in MTA1/ETS2-mediated chemoprevention and therapy in prostate cancer.

Citation Format: Urvi Kolhatkar, Kshiti Dholakia, Gabriela Sikorska, Avinash Kumar, Luis A. Martinez, Anait S. Levenson. Gnetin C as a candidate for targeted chemopreventive and therapeutic measures in prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 253.
Abstract 2533: Regulation of proliferation and metastasis gene expression by DAX-1 (NR0B1) in human breast cancer cells
Authors: Tzagarakis-Foster Christina
Published: August 2018

The orphan nuclear receptor DAX-1 (Dosage Sensitive Sex Reversal, Adrenal Hypoplasia Congenita, critical region on the X chromosome, gene 1) is known to serve an important role early on in mammalian sex determination as well as in the regulation of expression of steroid hormones. While it is unclear whether DAX-1 functions independently, DAX-1 has been demonstrated to act as a repressor of many nuclear hormone receptors, including ER, AR, PR, LRH-1 and SF-1. DAX-1 plays a role in select adult tissues, including gonadal tissue. However, it has also been shown to play a role in several types of cancer, though its specific function is not well understood. For example, in some types of cancer DAX-1 expression is upregulated, while in other cancers it is highly downregulated or completely absent. In an effort to better understand DAX-1 function both in normal and disease states, we examined the actions of DAX-1 in MCF7 breast cancer cells, which do not express the DAX-1 gene. We probed three different PCR arrays (breast cancer genes, proliferation genes and metastatic genes) to determine which genes were influenced by DAX-1 expression. With the introduction of DAX-1 in ERα positive breast cancer cells (MCF-7), we find that DAX-1 inhibits cell proliferation and blocks estradiol activation of key cell cycle regulatory genes, such as cyclin D1, as well as important metastatic genes. We show that DAX-1 binds directly to ERα and the ERα-DAX-1 complex binds to the cyclin D1 promoter. The outcome of DAX-1 expression in MCF7 cells is cell cycle arrest through the repression of key cell cycle regulatory genes. These results demonstrate that DAX-1 functions as a corepressor of ERα in MCF7 breast cancer cells by preventing the activation of growth-promoting genes and decreasing cell proliferation in response to estrogens. These findings could have significant implications for future drug development strategies specifically aimed at ER-interacting proteins such as DAX-1.

Citation Format: Christina Tzagarakis-Foster. Regulation of proliferation and metastasis gene expression by DAX-1 (NR0B1) in human breast cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2533.
Abstract 254: Chemopreventive effects of angiotensin II receptor type 2 agonist on prostate carcinogenesis by the downregulation of the androgen receptor
Authors: Uemura Hiroji , Ito Yusuke , Naiki-Ito Aya , Kato Hiroyuki , Suzuki Shugo , Kuno Toshiya , Takahashi Satoru
Published: August 2018

[Background] We previously reported that angiotensin II receptor blockers (ARB), anti-hypertensive drug, have chemopreventive and chemotherapeutic potential against prostate cancer via the reduction of androgen receptor (AR) expression. It is generally known that angiotensin II binds to two kinds of receptors, AT1R and AT2R, and the biological function of AT2R signaling has the opposite effect to that of AT1R signaling in many aspects. We therefore hypothesized that AT2R agonism might attenuate the proliferative activity in prostate cancer cells. In this study, we investigated the effects of the AT2R agonist Compound 21 (C21) designed by Vicore Pharma (Sweden), which is expected to play similar roles to an ARB, on prostate carcinogenesis using the transgenic rat for adenocarcinoma of prostate (TRAP) model previously established in our laboratory.

[Materials and Methods] In vitro analyses of the cell growth, Western blotting and PSA-reporter gene assays were performed using LNCaP and 22RV1 cells. TRAP rats at 6 weeks of age were randomly divided into 3 groups of 12 animals each and treated with C21 at 1 or 2 mg/kg/day in drinking water for 12 weeks. They were pathologically examined the classification as prostatic intraepithelial neoplasia and non-invasive adenocarcinoma. The proteins extracted from TRAP prostate glands were examined for Western blotting.

[Results] C21 reduced the proliferation activity of prostate cancer cells and down-regulated the PSA promoter activity, medium PSA levels and the AR protein expression. We discovered that C21 inhibited the progression of prostate carcinogenesis in TRAP rats and decreased the incidence of adenocarcinoma in the lateral prostate. A significant increase in the apoptotic index with activation of caspase 3 and 7 were observed by immunohistochemistry and Western blotting analyses. C21 also down-regulated the expression of AR significantly in TRAP rat prostate. C21 decreased the expression of AR and AR-relevant genes reduced the proliferation activity effectively in prostate cancer cells and TRAP rat prostate.

[Conclusion] The present study demonstrated that the epoch-making AT2R agonist C21 down-regulated the proliferation activity and the expression of AR both in vitro and in vivo. C21 is a promising drug not only for hypertension but also for human prostate cancer chemoprevention.

Citation Format: Hiroji Uemura, Yusuke Ito, Aya Naiki-Ito, Hiroyuki Kato, Shugo Suzuki, Toshiya Kuno, Satoru Takahashi. Chemopreventive effects of angiotensin II receptor type 2 agonist on prostate carcinogenesis by the downregulation of the androgen receptor [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 254.
Abstract 2540: TRIM24 is an oncogenic transcriptional co-activator of STAT3 in glioblastoma
Authors: Lv Deguan , Li Yanxin , Zhang Weiwei , Alvarez Angel A. , Tang Jianming , Hu Bo , Cheng Shi-Yuan , Feng Haizhong
Published: August 2018

Aberrant amplification and mutations of epidermal growth factor receptor (EGFR) are the most common oncogenic events in glioblastoma (GBM), but the mechanisms by which they promote aggressive pathogenesis are not well understood. Here, we determine that non-canonical histone signature acetylated H3 lysine 23 (H3K23ac)-binding protein tripartite motif-containing 24 (TRIM24) is upregulated in clinical GBM specimens and required for EGFR-driven tumorigenesis. In multiple glioma cell lines and patient-derived glioma stem cells (GSCs), EGFR signaling promotes H3K23 acetylation and association with TRIM24. Consequently, TRIM24 functions as a transcriptional co-activator and recruits STAT3, leading to stabilized STAT3-chromatin interactions and subsequent activation of STAT3 downstream signaling, thereby enhancing EGFR-driven tumorigenesis. Our findings uncover a pathway in which TRIM24 functions as a signal relay for oncogenic EGFR signaling and suggest TRIM24 as a potential therapeutic target for GBM that are associated with EGFR activation.

Citation Format: Deguan Lv, Yanxin Li, Weiwei Zhang, Angel A. Alvarez, Jianming Tang, Bo Hu, Shi-Yuan Cheng, Haizhong Feng. TRIM24 is an oncogenic transcriptional co-activator of STAT3 in glioblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2540.
Abstract 2546: Regulation of CAR-T cell therapy in real time using bispecific small molecule adaptors and monospecific competitors
Authors: Chu Haiyan , Lu Yingjuan , Lee Yong Gu , Wheeler Leroy , Nelson Mellissa , Westrick Elaine , Vetzel Marilynn , Klein Patrick J. , Low Philip S. , Leamon Christopher P.
Published: August 2018

Chimeric antigen receptor modified T cell (CAR-T) therapy has revolutionized personalized cancer treatment. The recent FDA approval of two CAR-T therapies for hematological cancers has marked a pivotal milestone in this new era of cellular therapies. CAR-T cells are genetically modified to become activated and proliferate in the presence of tumor antigens. In patients with high tumor burden and rapid T cell expansion, however, severe side effects including severe cytokine release syndrome (sCRS) and life-threatening cerebral edema may occur.

To “fine-tune” CAR-T cell activity in real time, we devised a three-pronged therapeutic strategy by using (1) 4-1BB-CD3ζ CARs expressing anti-fluorescein (anti-FITC) scFv instead of an anti-tumor ligand/self-antigen scFv, (2) low-molecular-weight bi-specific adaptors comprised of a FITC hapten linked to a tumor-specific ligand, and (3) competitors that can interfere with the adaptor/CAR-T interaction with tumor cells. Using folate-FITC (EC17) as the bi-specific adaptor molecule, we evaluated the performance of FITC-CAR-T cells in various folate receptor (FR)-positive tumor models. Our results show that CAR-T activation and proliferation in-vivo was EC17- and tumor FR-dependent. Treatment-related toxicity (sCRS) was observed but could be easily controlled, or even prevented, by adjusting the concentration, dosing frequency or timing of bi-specific adaptor administration. Importantly, animals experiencing sCRS could be rescued by administrating competitors of the bi-specific adaptor. In the case of EC17/CAR-T therapy, improved animal behavior was observed as early as a few hours after dosing with a rescue agent and a rapid reduction of interferon-γ was also detected. Circulating CAR-T cells remained functional, and could be re-activated following subsequent EC17 doses.

Taken together, our bi-specific adaptor/CAR-T approach offers a unique combination of a man-made hapten (FITC), flexible dosing control, and sCRS prevention/rescue without compromising antitumor activity or permanently removing CAR-T cells. Further studies are warranted to provide a rational basis for translating such therapeutic practice to the clinic.

Footnotes

HC and JL contributed equally to this work.

Citation Format: Haiyan Chu, Yingjuan Lu, Yong Gu Lee, Leroy Wheeler, Mellissa Nelson, Elaine Westrick, Marilynn Vetzel, Patrick J. Klein, Philip S. Low, Christopher P. Leamon. Regulation of CAR-T cell therapy in real time using bispecific small molecule adaptors and monospecific competitors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2546.
Abstract 2577: Predictive value of multigene assay for chemotherapy benefit in patients with HR+/HER2- early breast cancer
Authors: Kwon Mi Jeong
Published: August 2018

Our risk score based on a combination of multigene expression and clinical variables was validated to predict the risk of distant metastasis in hormone receptor-positive and human epidermal growth factor 2-negative (HR+/HER2-) early breast cancer in our previous study. In addition to its prognostic value, we investigated the predictive value of the risk score for adjuvant chemotherapy benefit in lymph node-negative (LN-), HR+/HER2- breast cancer. 346 patients who treated with hormone therapy (n = 203) alone or hormone therapy plus chemotherapy (n = 143) were classified as low-risk and high-risk group according to the risk score. There was a significant improvement in 10-year distant metastasis-free survival (DMFS) by the addition of adjuvant chemotherapy to hormone therapy in patients with a high risk score (26.5%, P = 0.003), whereas no benefit of chemotherapy was observed in those with a low risk score. The test for interaction between chemotherapy treatment and risk score was significant. The risk score also identified patients who will not benefit from chemotherapy among clinical high-risk group. Our study suggests that the risk score predicts the benefit of adjuvant chemotherapy in LN-, HR+/HER2- breast cancer and the addition of the risk score in the traditional cliniopathological factors may aid the improved treatment decisions.

Citation Format: Mi Jeong Kwon. Predictive value of multigene assay for chemotherapy benefit in patients with HR+/HER2- early breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2577.
Abstract 2585: Immunoseroproteomic profiling in autoantibodies to ENO1 as potential biomarkers in immunodiagnosis of osteosarcoma by serological proteome analysis (SERPA) approach
Authors: Li Jitian , Huang Manyu , Dai Liping , Han Zongchang , Qin Xiaofei , Xie Wen , Qian Wei , Li Wuyin , Zhang Jianying
Published: August 2018

Background: Osteosarcoma (OS) is the most common highly malignant primary solid bone-tumor. Despite its relatively low incidence rate among overall cancers, it remains one of the most harmful primary malignant tumors in childhood and adolescence. It is now evident that serum autoantibodies against tumor-associated antigens (TAAs) could be used as serological cancer biomarkers in types of cancers.

Methods: Serological proteome analysis (SERPA) approach was applied to profile anti-TAA autoantibody responses in sera from patients with OS, and Normal Human, and explore differences of these responses. This approach can detect autoantibodies to TAAs that could serve as clinical biomarkers and immunotherapeutic agents. Sera from OS, Osteochondroma (OC) and Normal Human Sera (NHS) were probed by immunoblotting against cellular proteins extracted from U2-OS and Saos-2 cell lines, with OS sera showing stronger immunoreactivity. MALDI-TOF/TOF Mass Spectrometry (MS) analysis of immunoreactive protein spots revealed that several OS sera contained autoantibodies to a number of proteins, particularly to alpha-enolase (ENO1).

Results: Analysis of 172 serum samples from patients with OS, OC and NHS by ELISA showed higher frequency of anti-ENO1 autoantibodies in OS sera compared to others. Interestingly, descant of ENO1 immunoreactivity was observed in most patients after treatments, which may imply a potential association between anti-ENO1 autoantibody titers and disease progression. Nine of twelve sera reacted strongly against purified ENO1, but 3 weakly against purified ENO1, which indicates 75.0% sera with positive optimal density values from ELISA were consistently positive in Western blotting. The expression of ENO1 in Osteosarcoma tissues was evaluated by immunohistochemistry in tumor microarray.

Conclusion: Our intriguing findings firstly demonstrate that ENO1 is one of autoantigens that elicit autoimmune responses in OS and can be used as biomarkers in immunodiagnosis and progression of OS.

Key words: Osteosarcoma (OS), Tumor-associated antigen (TAA), Serological proteome analysis (SERPA), ENO1, Immunodiagnosis.

Citation Format: Jitian Li, Manyu Huang, Liping Dai, Zongchang Han, Xiaofei Qin, Wen Xie, Wei Qian, Wuyin Li, Jianying Zhang. Immunoseroproteomic profiling in autoantibodies to ENO1 as potential biomarkers in immunodiagnosis of osteosarcoma by serological proteome analysis (SERPA) approach [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2585.
Abstract 2587: Imbalances in the disposition of estrogen and naphthalene in Taiwanese breast cancer patients
Authors: Lin Po-Hsiung , Chen Dar-Ren , Hsieh Wei-Chung , Ko Mao-Huei , Liao Yi-Lun
Published: August 2018

The aims of this study were to measure the background level of quinone metabolites of 17β-estradiol (E2), including E2-2,3-Q and E2-3,4-Q, and naphthalene quinone (1,2-NPQ and 1,4-NPQ)-derived protein adducts in human albumin (Alb) derived from breast cancer patients (n=143) and healthy controls (n=122) in Taiwanese women and to explore the relationships between these adducts with risk factors of breast cancer. Results from the analysis indicated that Alb adducts of estrogen quinones, including E2-2,3-Q-4-S-Alb and E2-3,4-Q-2-S-Alb were detected in all subjects with mean levels at 400 and 676 pmole/g in cancer patients and 204 and 67 pmole/g in controls, respectively. In addition, the mean levels of Alb adducts of 1,2-NPQ and 1,4-NPQ on human serum albumin were estimated to be 209 and 73.6 pmole/g in cancer patients and 113 and 174 pmole/g in controls, respectively. Levels of E2-2,3-Q-4-S-Alb correlated significantly with those of E2-3,4-Q-2-S-Alb. Similarly, levels of 1,4-NPQ-Alb correlated significantly with those of 1,2-NPQ-Alb. Additionally, we noticed that E2-2,3-Q-4-S-Alb and E2-3,4-Q-2-S-Alb positively correlated with 1,4-NPQ-Alb (p<0.001) whereas levels of E2-2,3-Q-4-S-Alb associated with 1,2-NPQ-Alb (p<0.01). Furthermore, we observed that ratio of E2-3,4-Q-2-S-Alb to E2-2,3-Q-4-S-Alb in breast cancer patients were ~5 fold greater than those of healthy controls whereas ratio of 1,2-NPQ-Alb to 1,4-NPQ-Alb in cancer patients were ~4 fold greater than those of healthy controls. This evidence suggests that the cumulative body burden of estrogen quinones is a significant indicator of the risk of developing breast cancer and that breast cancer risk is associated with the imbalances in the disposition of estrogen and naphthalene in Taiwanese women.

Citation Format: Po-Hsiung Lin, Dar-Ren Chen, Wei-Chung Hsieh, Mao-Huei Ko, Yi-Lun Liao. Imbalances in the disposition of estrogen and naphthalene in Taiwanese breast cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2587.
Abstract 259: Integrated multi-omics analyses reveal α-lipoic acid-regulated cell proliferation via Grb2-mediated signaling in colorectal cancer cells
Authors: Yang Lan , Hu Chunlei , LV Guoqing , Li Bei , Xiong Shaowei
Published: August 2018

Background: The use of antioxidants as cancer prevention and treatment agents has become a focus of research in recent years due to their limited adverse effects. Alpha lipoic acid (α-LA), a naturally occurring antioxidant and metabolic enzyme co-factor, has been reported to inhibit the growth of various cancer cells, but the precise signaling pathways that mediate the effects of α-LA on colorectal cancer cells development remain unclear.

Methods: In this study, we combined the use of an RNA sequencing (RNA-Seq) database and isobaric tag for relative and absolute quantitation (iTRAQ)-based quantitative proteomics data to investigate the dynamic genomic/proteomic response of human colorectal cancer cells (HT29) to α-LA stress. The CCK-8 assay was used to assess cell proliferation in CRC cell lines after α-LA treatment. The expression of proteins were evaluated by western blotting. Grb2 levels were restored in α-LA-treated cells by transfection of a plasmid carrying Grb2 and were reduced in CRC cells via specific siRNA-mediated knockdown.

Results: A total of 4,107 differentially expressed genes (2,259 downregulated and 1,848 upregulated) were identified via RNA-Seq in HT29 after exposure to α-LA for 24 h. Moreover, GO and KEGG pathway analyses showed that cancer-relevant cell membrane proteins were significantly affected. An interaction network analysis predicted that Grb2 may mediate the key target pathways activated by exposure to α-LA. In verifying the multi-omics results, Grb2 was confirmed to mediate the α-LA-induced inhibition of cell proliferation in vitro. Moreover, additional experiments indicated that Grb2 inhibition partially abolished EGF-induced phospho-EGFR and phospho-ERK1/2 activity. Furthermore, the analysis of human colorectal cancer specimens obtained from the GEO database showed that the expression of EGFR correlated with that of Grb2.

Conclusion: These findings provide a novel mechanism by which α-LA regulates cell colorectal cancer proliferation via the down-regulation of growth factor-stimulated Grb2 signaling.

Citation Format: Lan Yang, Chunlei Hu, Guoqing LV, Bei Li, Shaowei Xiong. Integrated multi-omics analyses reveal α-lipoic acid-regulated cell proliferation via Grb2-mediated signaling in colorectal cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 259.
Abstract 2591: Role of EGFR-AS1 lncRNA in growth factor addiction and treatment response in squamous cell cancers
Authors: Tan Daniel SW , Chong Fui-Teen , Leong Hui-Sun , Toh Shen Yon , Lau Dawn P. , Kwang Xue Lin , Zhang Xiaoqian , Tan Gek San , Skanderup Anders J. , Lim Tony KH , Dasgupta Ramanuj , Iyer N Gopalakrishna
Published: August 2018

Squamous-cell cancers (SCCs) represent one of the commonest lethal malignancy worldwide. Despite evidence demonstrating that majority are addicted to Epidermal Growth Factor Receptor (EGFR)-signaling, targeting with monoclonal antibodies or tyrosine-kinase inhibitors (TKIs) has been met with limited success. We recently demonstrated that TKI-sensitivity is modulated by a long non-coding RNA (lncRNA) situated in the antisense strand of EGFR (EGFR-AS1). ‘Synonymous' alterations in EGFR-AS1 affected TKI-response in patient-derived models, and could be used to predict response in a small patient cohort. The lncRNA likely functions in cis by altering EGFR splicing, favouring expression of a truncated EGFR isoform (isoform D), with previously unknown function. Importantly, mediation of this effect requires EGFR ligand derived from paracrine or autocrine sources. Remarkably, even modest EGFR-AS1 knockdown showed profound effects on TKI sensitivity and tumor growth in vivo; the latter suggesting lncRNA-addiction. TKI-resistance models were established from patient-derived lines, through serial passaging with sub-lethal drug doses. Detailed analyses of four of these models demonstrate alterations that affect each of the steps involved in this addiction pathway: ligand binding, EGFR-AS1 expression/amplification and isoform D expression. Based on our mechanistic insights, we propose that patient-response to EGFR inhibitors is contingent on establishing a comprehensive suite of inter-related biomarkers as delineated here. This data also supports a novel therapeutic approach that involves modulating a lncRNA and/or splice variants of a well-established oncogenic driver.

Citation Format: Daniel SW Tan, Fui-Teen Chong, Hui-Sun Leong, Shen Yon Toh, Dawn P. Lau, Xue Lin Kwang, Xiaoqian Zhang, Gek San Tan, Anders J. Skanderup, Tony KH Lim, Ramanuj Dasgupta, N Gopalakrishna Iyer. Role of EGFR-AS1 lncRNA in growth factor addiction and treatment response in squamous cell cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2591.
Abstract 2593: AR-V7 and AR-V9 expression is not predictive of response to AR-axis targeting agents in metastatic castration-resistant prostate cancer
Authors: To Sarah Q. , Kwan Edmond , Fettke Heidi , Mant Andrew , Docanto Maria , Martelotto Luciano , Bukczynska Patricia , Ng Nicole , Graham Lisa-Jane , Parente Phillip , Pezaro Carmel , Mahon Kate , Horvath Lisa , Todenhöfer Tilman , Azad Arun
Published: August 2018

In 2014, a landmark study was published demonstrating that androgen receptor splice variant (AR-V) AR-V7 expression was a negative predictive biomarker for response to abiraterone acetate and enzalutamide in metastatic castration-resistant prostate cancer (mCRPC) patients. However, these results were not supported by the recently reported ARMOR3-SV phase III clinical trial, which employed an identical circulating tumor cell assay to assess AR-V7 expression. Therefore, the predictive utility of AR-V7 expression in mCRPC remains uncertain, as does any potential association between other AR splice variants and treatment response. To further investigate, we designed a highly sensitive and specific whole blood assay for detecting AR-V7 and AR-V9. We then examined for a correlation between baseline AR-V7/V9 status and treatment outcome in 37 mCRPC patients commencing abiraterone or enzalutamide. Blood was taken in a PAXgene RNA tube at baseline prior to the commencement of therapy and at end of treatment (if applicable). 24% (9/37) of patients were AR-V-positive. Notably, PSA response rates did not significantly differ between AR-V-positive (6/9) and AR-V-negative (18/28) patients (66% vs. 64%, p=0.896). Likewise, median PSA progression-free survival was not significantly different between AR-V-positive and AR-V-negative patients (9.2 months vs. not reached; p=0.894). Additionally, we identified 2 patients who were AR-V7 negative at baseline but had converted to AR-V7 positive in their end-of-treatment sample. This was associated with much shorter PSA-PFS than those that remained negative (2.58 months vs. no reached), suggesting gain of AR-V expression may be a marker of acquired resistance. These data, which support the findings of the pivotal ARMOR3-SV clinical trial, suggest that baseline AR-V expression does not predict outcomes in mCRPC patients receiving abiraterone or enzalutamide.

Citation Format: Sarah Q. To, Edmond Kwan, Heidi Fettke, Andrew Mant, Maria Docanto, Luciano Martelotto, Patricia Bukczynska, Nicole Ng, Lisa-Jane Graham, Phillip Parente, Carmel Pezaro, Kate Mahon, Lisa Horvath, Tilman Todenhöfer, Arun Azad. AR-V7 and AR-V9 expression is not predictive of response to AR-axis targeting agents in metastatic castration-resistant prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2593.
Abstract 2600: Resistance biomarkers in patients with head and neck squamous cell carcinoma treated with cetuximab
Authors: Kamal Maud , Leblanc Olivia , Vacher Sophie , Lecerf Charlotte , Jeannot Emmanuelle , Klijanienko Jerzy , Berger Frederique , Hoffmann Caroline , Calugaru Valentin , Badois Nathalie , Chilles Anne , Lesnik Maria , Krhili Samar , Jouffroy Thomas , Bieche Ivan , Tourneau Christophe Le
Published: August 2018

BACKGROUND: Cetuximab, a monoclonal antibody targeting EGFR, improves overall survival in the locally advanced setting in combination with radiotherapy and in first-line recurrent setting in combination with chemotherapy in HNSCC patients. No predictive biomarker of efficacy of cetuximab in these settings. We aimed at identifying biomarkers of sensitivity/resistance to cetuximab.

PATIENTS AND METHODS: HNSCC patients treated with cetuximab at Institut Curie, for which complete clinicopathological data and formalin-fixed, paraffin-embedded (FFPE) tumor tissue were available and collected before cetuximab treatment, were included in this retrospective study. Immunohistochemistry analyses of PTEN and EGFR were performed to assess expression levels. PIK3CA and KRAS mutations were analyzed using high resolution melting (HRM) and Sanger sequencing. The predictive value of these alterations on progression-free survival (PFS) was evaluated.

RESULTS: PIK3CA and KRAS/HRAS mutations were associated with poor PFS in HNSCC patients treated with cetuximab in first-line recurrence setting but not in patients treated with cetuximab in combination with radiotherapy. PTEN loss of expression had a negative prognostic impact in HNSCC patients treated with cetuximab and radiotherapy, while EGFR high expression was not found to be a sensitivity biomarker for cetuximab in our patient population.

CONCLUSIONS: PIK3CA and RAS mutations were resistance biomarkers of cetuximab in first-line recurrent setting, whereas PTEN loss was a resistance biomarker of cetuximab when given in combination with radiotherapy.

Citation Format: Maud Kamal, Olivia Leblanc, Sophie Vacher, Charlotte Lecerf, Emmanuelle Jeannot, Jerzy Klijanienko, Frederique Berger, Caroline Hoffmann, Valentin Calugaru, Nathalie Badois, Anne Chilles, Maria Lesnik, Samar Krhili, Thomas Jouffroy, Ivan Bieche, Christophe Le Tourneau. Resistance biomarkers in patients with head and neck squamous cell carcinoma treated with cetuximab [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2600.
Abstract 265: Epi-magnolin suppresses EGF-induced neoplastic cell transformation by inhibition of Akt/mTOR signaling pathway in JBC Cl41 cells
Authors: Lee Cheol-Jung , Yoo Sun-Mi , Kim Seung-Min , Cho Seon-Yeon , Park Juhee , Shin Yu-Mi , Cho Yong-Yeon , Lee Hye Suk
Published: August 2018

The phosphatidylinositol-3-kinase (PI3K)/Akt/the mammalian target of rapamycin (mTOR) signaling pathway is frequently activated in human cancer and plays a pivotal role in cell proliferation and transformation. In this study, we reveal epi-magnolin, a phytochemical found in Magnolia flos, as an inhibitor of Akt/mTOR signaling pathway. Epi-magnolin inhibits EGF-induced Akt phosphorylation at Thr308 and Ser473, but not extracellular signal-regulated kinases (ERKs)/ribosomal S6 kinase 2 (RSK2) signaling pathway. Moreover, we demonstrate that epi-magnolin suppresses JB6 cell proliferation by impairing EGF-induced G1/S cell cycle transition in a dose-dependent manner. Notably, epi-magnolin abrogates phosphorylation of c-Jun at Ser63 and 73 as well as total c-Jun protein level, which leads to downregulation of AP-1 transactivation activity. The inhibition effect of Akt/mTOR signaling pathway and AP-1 transactivation activity by epi-magnolin suppressed EGF-induced anchorage-independent cell transformation. Based on these results, epi-magnolin might be a chemopreventive agent by targeting Akt/mTOR signaling pathway.

Key words: chemoprevention, cell transformation, Akt/mTOR signaling pathway

Citation Format: Cheol-Jung Lee, Sun-Mi Yoo, Seung-Min Kim, Seon-Yeon Cho, Juhee Park, Yu-Mi Shin, Yong-Yeon Cho, Hye Suk Lee. Epi-magnolin suppresses EGF-induced neoplastic cell transformation by inhibition of Akt/mTOR signaling pathway in JBC Cl41 cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 265.
Abstract 2654: Immunologic and prognostic correlates of WISP1 in prostate cancer
Authors: Gaudreau Pierre-Olivier , Clairefond Sylvie , Boulay Pierre-Luc , Chrobak Pavel , Allard Bertrand , Pommey Sandra , Saad Fred , Young Marian , Stagg John
Published: August 2018

Background: Avoidance of immune destruction and tumor-promoting inflammation are equally important cancer hallmarks. In the context of prostate cancer, inflammatory markers and high levels of immune infiltrates have been associated with shorter biochemical recurrence (BCR)-free survival. WNT1 Inducible Signaling Pathway (WISP1) has been implicated in prostate cancer metastasis and the regulation of inflammation in diverse benign diseases. Thus, the objectives of this study were: 1) to assess the prognostic value of WISP1 in human prostate cancer, and 2) to determine the association of WISP1 to the inflammatory landscape specific to this disease.

Methods: A tumor microarray (TMA) was constructed with radical prostatectomy specimens of 285 prostate cancer patients. Multicolor manual immunofluorescence (IF) was performed to simultaneously detect WISP1, CD8 and cytokeratins 8 and 18. WISP1 expression levels were determined by the mean fluorescence intensity (MFI) in stromal, epithelial, cytoplasmic and nuclear (DAPI) areas in each core, and CD8+ cell density was determined for each compartment by dividing cell count by the percentage of the core occupied by the compartment. Finally, the prostate cancer TCGA dataset (n = 548) was used to validate the prognostic value of WISP1 mRNA expression, as well as its association to CD8+ lymphocytes using previously validated gene signatures (Becht et al., 2016).

Results: IF analyses of our TMA revealed that high levels of WISP1 in normal adjacent epithelium are significantly associated with shorter BCR-free survival in Kaplan-Meier (log-rank = 4.246, p = 0.039) and univariate Cox regression analyses (hazard ratio = 1.477; p = 0.042), but not in multivariate Cox regression analyses (hazard ratio = 1.381; p = 0.101). Furthermore, a significant correlation was found between WISP1 expression and CD8+ cell density. Gene expression analyses further showed that WISP1-high prostate tumors are associated with a CD8+ lymphocyte gene enrichment profile, and confirmed that patients with WISP1-high prostate tumors have reduced BCR-free survival (Wilcoxon rank, p = 0.003).

Conclusions: Overall, our results support a negative prognostic association for WISP1 as well as a proinflammatory role. WISP1 may represent a relevant target for the improvement of prostate cancer immunotherapy.

Citation Format: Pierre-Olivier Gaudreau, Sylvie Clairefond, Pierre-Luc Boulay, Pavel Chrobak, Bertrand Allard, Sandra Pommey, Fred Saad, Marian Young, John Stagg. Immunologic and prognostic correlates of WISP1 in prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2654.
Abstract 2662: Indenoisoquinoline topoisomerase I inhibitors target the DNA G-quadruplex formed in the c-Myc promoter and cause MYC downregulation
Authors: Wang Kaibo , Elsayed Mohamed S. A. , Wu Guanhui , Cushman Mark , Yang Danzhou
Published: August 2018

The inhibition of DNA topoisomerase I (Top1) has proven to be a successful approach toward the design of anticancer agents. Indenoisoquinoline derivatives have been designed and developed as Top1 inhibitors and can overcome some shortcomings associated with the camptothecin Top1 inhibitors, resulting in three indenoisoquinoline compounds, indotecan (LMP 400), indimitecan (LMP776), and LMP744 entering Phase I clinical trials at the National Cancer Institute. However, some active indenoisoquinolines did not show potent Top1 inhibition, suggesting a separate mechanism of action. c-Myc is one of the most commonly deregulated genes in human cancers; a DNA G-quadruplex (G4) formed in the proximal promoter region of c-Myc has been found to function as a transcriptional silencer and be amenable to small molecule targeting. As indenoisoquinolines share structure similarity to our c-Myc G-quadruplex (MycG4)-interactive compounds, we hypothesized that indenoisoquinolines could stabilize MycG4 and downregulate MYC transcription. Using a fluorescence resonance energy transfer (FRET) assay, we examined the MycG4 stabilization activity of 56 indenoisoquinoline compounds that we previously developed as Top1 inhibitors. Notably, 26 of the 56 compounds decreased the fluorescence intensity by at least 50%, and the 10 most potent compounds reduced fluorescence intensities by over 70%, indicating that these indenoisoquinolines are effective MycG4 stabilizers. The identified compounds were further characterized by fluorescence anisotropy, circular dichroism, and nuclear magnetic resonance for MycG4 interactions, followed by western blot assays for MYC downregulation. Significantly, the compounds with good MycG4 binding activity and affinity exhibited significant dose-dependent reduction of MYC expression, indicating that targeting the c-Myc promoter G-quadruplex is a likely mechanism of action for these active anticancer compounds. Furthermore, some active indenoisoquinolines exhibited both MYC downregulation and Top1 inhibition, suggesting that dual targeting c-Myc G-quadruplex and Top1 may represent a novel mechanism of action for anticancer drug design.

Citation Format: Kaibo Wang, Mohamed S. A. Elsayed, Guanhui Wu, Mark Cushman, Danzhou Yang. Indenoisoquinoline topoisomerase I inhibitors target the DNA G-quadruplex formed in the c-Myc promoter and cause MYC downregulation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2662.
Abstract 2666: Subtype-selective lethal molecules disrupt the regulatory module that drives high-risk neuroblastoma
Authors: Stokes Michael E. , Vasciaveo Alessandro , Small Jonnell Candice , Rajbhandari Presha , Lopez Gonzalo , Califano Andrea , Stockwell Brent R.
Published: August 2018

Neuroblastoma (NBL) is a tumor that is derived from the developing neural crest, resulting in approximately 15% of pediatric cancer deaths. This cancer is characterized by multiple tumor subtypes that vary in their aggressiveness and clinical prognosis. Though MYCN amplification is associated with an aggressive subtype and poor prognosis, recent molecular classification identified a novel aggressive subtype driven by a mesenchymal gene signature. To understand the molecular mechanisms underpinning each subtype, network-based analysis identified key transcriptional regulators for each subtype that act in concert to drive tumor pathology. We hypothesize that chemical inhibitors disrupting this regulatory module will have greater chance of success in vivo, by targeting the specific drivers of the tumor subtype. In an effort to identify subtype-selective lethal molecules that could be developed into targeted therapies, we screened ~5500 bioactive molecules across a panel of four NBL cell lines representing either MycNAMP or the newly identified mesenchymal subtype (MESN). A number of subtype selective compounds were identified, and their effect on the regulatory module was evaluated using high-throughput transcriptome analysis (PLATE-Seq) (Bush EC et al., 2017) followed by Virtual Inference of Protein activity by Enriched Regulon (VIPER) analysis (Alvarez MJ et al., 2016). This analysis revealed 15 compounds that exhibited greater potency in MycNAMP cells, and inverted the MR signature that characterizes this subtype. Compounds that reverted the signature caused destabilization of MycN through diverse mechanisms, highlighting new therapeutic approaches to targeting the MycNAMP subtype. This screening strategy also identified MESN-selective compounds, including multiple statin drugs that inhibit mevalonate biosynthesis in cells. The subtype-selectivity of these well-studied drugs is being used to define their lethal mechanisms in the MESN subtype, and to understand how MycNAMP cells evade their inhibitory effects. Our multifaceted approach, including cell line-selective chemical screening coupled with high-throughput transcriptome and network analysis, can serve as a framework for future drug discovery in a variety of cancers.

Citation Format: Michael E. Stokes, Alessandro Vasciaveo, Jonnell Candice Small, Presha Rajbhandari, Gonzalo Lopez, Andrea Califano, Brent R. Stockwell. Subtype-selective lethal molecules disrupt the regulatory module that drives high-risk neuroblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2666.
Abstract 2677: A natural product-derived Compound A effectively targets both cancer stem and non-stem cells in NSCLC
Authors: Hyun Seung Yeob , Le Huong T. , Cho Jaebeom , Min Hye-Young , Lee Ho-Young
Published: August 2018

Cancer stem-like cells (CSCs) contribute to tumor recurrence and chemoresistance. Hence, strategies eradicating CSCs are crucial for effective anticancer therapies. Here, we demonstrate transcriptional upregulation of the heat shock proteins (Hsp90 and Hsp70) and their co-chaperones and enhanced activities of the Hsp system in both non-CSCs and CSCs in non-small cell lung cancer (NSCLC) cells. Genetic and pharmacologic strategies targeting Hsps eliminated both CSCs and non-CSCs of NSCLC, suggesting the functional role of the Hsp system in the two populations in NSCLC. We further identified Compound A, a natural product-derived compound, as a novel Hsp70 inhibitor eliminating both the CSC and non-CSC populations in NSCLC. Compound A inhibited the sphere-forming ability of NSCLC CSCs by inducing apoptosis. Compound A also suppressed the viability and colony-forming abilities of NSCLC cells (non-CSCs) and their sublines carrying acquired chemoresistance by inducing apoptosis with minimal toxicity in normal cells derived from various organs. Mechanistically, Compound A disrupted Hsp70 function by binding to the ATP-binding pockets of Hsp70. These data suggest the rationale to target the Hsp system for controlling both CSCs and non-CSCs in NSCLC and the potential of Compound A as a natural Hsp70 inhibitor to eliminate the two populations with limited toxicities.

Citation Format: Seung Yeob Hyun, Huong T. Le, Jaebeom Cho, Hye-Young Min, Ho-Young Lee. A natural product-derived Compound A effectively targets both cancer stem and non-stem cells in NSCLC [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2677.