bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 5322: Normal breast tissue 5-hydroxymethylcytosine is enriched at DNA regulatory elements of breast cancer cells
Authors: Wilkins Owen Michael , Johnson Kevin C. , Houseman E. Andres , King Jessica E. , Marsit Carmen J. , Christensen Brock C.
Published: August 2018

DNA methylation is an established modulator of gene expression in normal mammalian cells. Emerging evidence suggests that the oxidized 5-methylcytosine (5mC) product, 5-hydroxymethylcytosine (5hmC), has distinct biological functions and its dysregulation may contribute to cancer pathogenesis. While 5hmC levels in normal breast tissue have been shown to be elevated relative to several other tissue types, we lack a complete knowledge of the genomic distribution of 5hmC in breast tissue, as well as its potential biological functions. Here, we determined the genome-wide distribution of 5hmC and 5mC using methylation array data from 18 normal breast tissue samples. To disambiguate 5hmC from 5mC, we performed parallel processing of bisulfite and oxidative-bisulfite treated DNA, followed by statistical estimation of the 5mC and 5hmC proportions. Based on the distribution of 5hmC, we identified genomic loci with consistently elevated levels of 5hmC across normal breast tissues. In addition, we showed 5hmC is enriched within transcriptionally active chromatin in breast myoepithelial cells, marked by H3K4 trimethylation. Conversely, 5hmC was depleted within active promoters (H3K9ac-marked DNA) and transcriptionally inactive chromatin (H3K9me3 and H3K27me3-marked DNA). Importantly, the loci with high 5hmC in normal breast tissue were enriched among regulatory elements, including transcription factor binding sites, in transformed normal-like breast MCF10A cells, as well as in multiple breast cancer cell lines. These findings provide a genome-wide distribution of 5hmC in normal breast tissue. Furthermore, these findings identify DNA-regulatory regions in breast cancer cell lines that show statistical enrichment for those sites with elevated 5hmC in normal breast tissue, suggesting deregulation of 5hmC within these elements may contribute to breast carcinogenesis.

Citation Format: Owen Michael Wilkins, Kevin C. Johnson, E. Andres Houseman, Jessica E. King, Carmen J. Marsit, Brock C. Christensen. Normal breast tissue 5-hydroxymethylcytosine is enriched at DNA regulatory elements of 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 5322.
Abstract 534: Oncogenes alter mammary epithelial cell lineage identity prior to tumor formation
Authors: Breindel Jerrica , Nampanya Felix , Datye Aditya , Miller Daniel H. , Gupta Piyush , Kuperwasser Charlotte
Published: August 2018

Background: Breast cancer is a heterogeneous disease encompassing multiple subtypes that differ in their molecular profiles, clinical course of progression, and response to therapeutics. Interestingly, breast cancers fall broadly into luminal and basal subtypes, which resemble the normal luminal and basal epithelial cells of the breast. This correlation suggests that the molecular mechanisms controlling epithelial cell lineage identity during normal mammary development may also influence tumor subtype during cancer formation. Since many breast cancers are driven by oncogenes that are important for normal mammary development, we hypothesize that dysregulated oncogene signaling may alter mammary epithelial cell lineage identity at an early step of cancer initiation, priming the breast tumor subtype that will be formed upon full tumorigenesis.

Methods: Human breast cell lines, MCF10a and MCF10f, and primary human breast tissues were infected with virus expressing single breast cancer oncogenes. Flow cytometry and quantitative RT-PCR were performed on breast cell lines to determine changes in the balance of luminal to basal cells and expression of luminal or basal gene sets. Primary tissues were grown in hydrogels and stained for luminal and basal markers to determine the effect of oncogene expression on the growth of mammary ductal structures. Mouse tumor models, MMTV-Myc and MMTV-Wnt1, were investigated for changes in their mammary epithelial architecture by histology and flow cytometry at ages prior to tumor formation.

Results: Oncogene overexpression in human breast cell lines causes shifts in basal and luminal cell balance that correlate with changes seen in mammary ductal growth in hydrogel cultures of primary human breast epithelial cells. In mouse models, individual oncogenes alter mammary epithelial architecture and cell balance at early stages prior to tumor formation. In both models, individual oncogenes are able to regulate mammary epithelial cell lineage identity in the absence of other tumor-initiating signals, indicating that oncogenes may influence breast cancer subtype through mammary epithelial cell lineage regulation at early stages of cancer progression.

Citation Format: Jerrica Breindel, Felix Nampanya, Aditya Datye, Daniel H. Miller, Piyush Gupta, Charlotte Kuperwasser. Oncogenes alter mammary epithelial cell lineage identity prior to tumor formation [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 534.
Abstract 5376: Whole-exome sequencing of acquired nevi identifies novel mechanisms for development and maintenance of benign neoplasms
Authors: Stark Mitchell S. , Tan Jean-Marie , Tom Lisa , Jagirdar Kasturee , Lambie Duncan , Schaider Helmut , Soyer H. Peter , Sturm Richard A.
Published: August 2018

Background: Acquired melanocytic nevi (AMN) are often mimicking melanoma and ~30% of all melanomas arise within a pre-existing nevus. However, the melanoma transformation rate of each nevus is rare despite the detection of oncogenic mutations BRAF or NRAS mutations in 100% of nevi.Objective: To identify the underlying genetic mechanisms for nevus development.Methods: Nevi, adjacent normal skin, and saliva were sampled from a cross-sectional study. All nevi were clinically, dermoscopically, and histopathologically documented. Using whole-exome sequencing (WES) we assessed the somatic mutational landscape, mutation signatures and copy-number aberrations (CNA) in 30 acquired melanocytic nevi and matching normal skin.Results: In addition to identifying somatic mutations, we confirm the presence of mutational signatures relating to age and ultra-violet radiation (UVR) which mirrors those observed in melanomas of the skin. In matching normal skin of all nevi, we rarely observed the presence of a UVR mutation signature (10% vs. 97% in nevi) despite being exposed to the same amount of UVR as the associated naevus. Instead, we have identified the predominance of defective DNA repair mutation signatures (93%) which we postulate creates the environment for melanocyte transformation sufficient for nevi and perhaps de novo melanoma growth. In copy number aberration (CNA) analysis, in nevi with copy number loss of tumour suppressor genes (TSG), these were balanced by loss of potent oncogenes. Moreover, reticular and non-specific patterned nevi revealed an increased (p<0.0001) number of CNA as compared with globular patterned nevi. Conclusion: The mutation signature data generated in this study confirms that UVR and defective DNA repair mechanism strongly contributes to nevogenesis. The observed copy number changes reflect at a genomic level, the dermoscopic differences of AMN. Lastly, we propose that the balanced loss of TSGs and oncogenes is a protective mechanism of AMN.

Citation Format: Mitchell S. Stark, Jean-Marie Tan, Lisa Tom, Kasturee Jagirdar, Duncan Lambie, Helmut Schaider, H. Peter Soyer, Richard A. Sturm. Whole-exome sequencing of acquired nevi identifies novel mechanisms for development and maintenance of benign neoplasms [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 5376.
Abstract 5407: MicroRNA expression analysis of advanced colorectal cancer reveals a microRNA signature with prognostic and predictive value
Authors: Zeng Zhaolei , Lu Jiahua , Zuo Zhixiang , Zhao Qi , Xu Ruihua
Published: August 2018

Background

Prognostic and predictive markers are needed to predict the clinical outcomes of patients with advanced colorectal cancer (CRC) who receive standard first-line treatments. We performed a prospective cohort study in patients with advanced CRC to identify a miRNA signature that could predict the benefit of receiving first-line chemotherapy for these patients.

Methods

Twenty-one paired tumours and adjacent normal tissues were collected from patients with advanced CRC and analysed by miRNA microarrays. Between tumour and normal tissues, 33 miRNAs were differentially expressed. The differential expression of these miRNAs was confirmed by qRT-PCR using paraffin-embedded specimens from another group of 76 patients from a prospective cohort study. A two-miRNA-based signature was obtained using the least absolute shrinkage and selection operator (LASSO) Cox regression model based on the association between the expression of each miRNA and the progression-free survival (PFS) time of individual patients. Internal and external validation cohorts, including 45 and 50 patients with advanced CRC, respectively, were performed to validate the prognostic and predictive accuracy of this signature.

Results

A signature based on two miRNAs, miR-125b-2-3p and miR-933, was built by the LASSO model. CRC patients were classified into high- and low-risk groups for disease progression based on this tool. The patients with high risk scores generally had worse PFS than those with lower risk scores. In the training set, the average PFS was 23.906 months for the low-risk group and 9.010 months for the high-risk group (hazard ratio [HR] 2.535, 95% CI 1.478-4.348, p=0.001). In the internal validation set, the average PFS was 14.029 months for the low-risk group and 6.334 months for the high-risk group (HR 3.173, 95% CI 1.415-7.116, p=0.005). In the external validation set, the average PFS was 16.815 months for the low-risk group and 7.657 months for the high-risk group (HR 2.498, 95% CI 1.281-4.871, p=0.007). Furthermore, we detected miR-125b-2-3p associated with CRC cell sensitivity to first-line chemotherapy. The two-miRNA-based signature was an independent prognostic factor for predicting the outcome of patients with metastatic CRC receiving first-line chemotherapy.

Citation Format: Zhaolei Zeng, Jiahua Lu, Zhixiang Zuo, Qi Zhao, Ruihua Xu. MicroRNA expression analysis of advanced colorectal cancer reveals a microRNA signature with prognostic and predictive value [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 5407.
Abstract 5414: The correlation between the expression of microRNA hsa-miR-101 and the prognosis of the patient with hepatocellular carcinoma
Authors: Nakajima Go , Hayashi Kazuhiko
Published: August 2018

Aim: MicroRNAs (miRNA) are small RNAs that regulate gene expression at the post-transcriptional level, and they play a various role in cancer cell such as proliferation, migration and metastasis. Our previous study identified forty-nine miRNAs that are differentially expressed by comparing 26 pair samples of hepatocellular carcinoma (HCC) tumor and adjacent liver tissue using next-generation sequencer system. One of them, hsa-miR-101 is chosen in this validation study. The hsa-miR-101 expression in HCC tumor samples and its adjacent liver tissues were measured by real-time PCR, and were examined the correlation between the miRNA expression and clinical data.

Patients and Methods: Forty-three patients diagnosed as HCC had undergone surgical removal from 1991 to 1997 at the Department of Surgery, Institute of Gastroenterology, Tokyo Women's Medical University, Japan. The formalin-fixed paraffin embedded samples were prepared using the standard protocol. The paraffin blocks were cut into 10 micrometer sections, and the tumor and its adjacent non-tumor liver tissue were collected using laser-captured microdissection and total RNA including miRNA fraction were isolated. After synthesized cDNA using miRNA specific primer, real-time PCR was performed using miRNA specific primer/probe.

Results: The expression of hsa-miR-101 in tumor tissue was downregulated compared to adjacent liver tissue (P=0.003). No significant differences were obtained in survival time between higher or lower intratumoral expression level (P=0.8039). The patients were divided into two groups, higher/lower hsa-miR-101 expression in the tumor or in the adjacent liver tissue, the group of the higher expression in adjacent liver tissue and the lower in tumor was longer survival time compared to the other groups (P=0.0184).

Conclusion: The hsa-miR-101 expression may be related to tumorigenesis, and both the expression in the tumor and in the adjacent liver tissue may be potential prognostic factor for HCC patients.

Citation Format: Go Nakajima, Kazuhiko Hayashi. The correlation between the expression of microRNA hsa-miR-101 and the prognosis of the patient with hepatocellular 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 5414.
Abstract 5420: Nuclear PTEN directly regulates androgen receptor activity in prostate cancer
Authors: Nguyen Yen T. , Rodriguez-Nieves Jose A. , Yang Qi , VanderWeele David
Published: August 2018

The deletion of PTEN, a negative regulator of the PI3K pathway, is among the most frequent genomic alterations in prostate cancer. Attempts to target this alteration using PI3K pathway inhibitors, however, have yielded little clinical benefit for patients, and the function of PTEN loss in prostate cancer progression is not fully understood. Prostate cancers lacking PTEN are less responsive to therapy targeting the Androgen Receptor (AR), a dominant driver of prostate cancer growth, but how PTEN function interacts with AR activity is not clear. We used immunoblotting, immunoprecipitation, proximity ligation assay, chromatin immunoprecipitation, and transcriptome sequencing in cells with endogenous PTEN or PTEN knocked down to evaluate the interactions between these major factors in prostate cancer progression. We demonstrate that PTEN interacts with the Androgen Receptor in the nucleus, and PTEN can bind chromatin at known Androgen Response Elements. Stimulation of cells with androgen and other media components leads to accumulation of phosphorylated (inactive) PTEN, loss of nuclear PTEN, and decreased PTEN-AR interaction. Transcriptome analysis of cells with PTEN knocked down demonstrates increased expression of AR pathway genes, even in the absence of androgen stimulation. These results suggest nuclear PTEN may play a direct role in negative regulation of the Androgen Receptor, with implications for management of PTEN-negative prostate cancers.

Citation Format: Yen T. Nguyen, Jose A. Rodriguez-Nieves, Qi Yang, David VanderWeele. Nuclear PTEN directly regulates androgen receptor activity 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 5420.
Abstract 5423: Lysine-52 stabilizes the MYC oncoprotein through a SCFFBXW7-independent mechanism
Authors: Melo Jason De , Kim Sam S. , Lourenco Corey , Resetca Diana , Sunnerhagen Maria , Raught Brian , Penn Linda Z.
Published: August 2018

The oncogenic transcription factor c-MYC (MYC) is deregulated, and often overexpressed, in more than 50% of cancers. MYC deregulation is associated with poor prognosis and aggressive disease, suggesting that the development of therapeutic inhibitors targeting MYC would dramatically impact patient care and outcome. MYC is a highly regulated transcription factor, with a protein and mRNA half-life of approximately 30 min. The most extensively studied pathway regulating MYC protein stability involves ubiquitylation and proteasomal degradation mediated by the E3-ligase, SCFFBXW7. Here we provide evidence for a SCFFBXW7-independent regulatory mechanism centered on Lysine 52 (K52) within MYC Box I (MBI) of the MYC protein. This residue has been shown to be post-translationally modified by both ubiquitylation and SUMOylation, hinting at the interplay of post-translational modifications at this site, and the importance of this residue. We demonstrate that mutation of K52 to arginine (R) renders the MYC protein more labile. Mechanistically, we show that the degradation pathway regulated by K52 is independent of the Cullin-Ring-Ligase (CRL) family of E3-ligases, which includes not only the canonical SCFFBXW7, but also a number of other known MYC-targeting E3-ligases, such as SCFSKP2, SCFβTCRP, SCFFBXO28 and DCXTRUSS. To characterize this degradation pathway further we will utilize unbiased and targeted experiments to elucidate the proteins involved. Taken together, our data identifies a novel regulatory pathway centred on K52 that may be exploited for the development of anti-MYC therapeutics.

Citation Format: Jason De Melo, Sam S. Kim, Corey Lourenco, Diana Resetca, Maria Sunnerhagen, Brian Raught, Linda Z. Penn. Lysine-52 stabilizes the MYC oncoprotein through a SCFFBXW7-independent mechanism [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 5423.
Abstract 545: NOTCH1 co-expression analysis reveals novel insights underlying its opposing effects as an oncogenic and tumor suppressor in lung cancer
Authors: Sinicropi-Yao Sara L. , Carbone David P. , Coombes Kevin R. , Amann Joseph M. , Lopez David Lopez
Published: August 2018

Background: Aberrations in the family of Notch receptors (1, 2, 3, and 4) have been implicated in a range of solid tumors, including lung cancer. NOTCH1 biology is complex where Notch plays an oncogenic and tumor suppressor role in lung adenocarcinoma and lung squamous cell carcinoma, respectively. Although the role of Notch in cancer development and progression has received increased appreciation in recent years, there is still a lack of understanding of the mechanisms underlying these opposing activities in lung cancer.

Methods: The Cancer Genome Atlas datasets were used to examine gene co-expression patterns of Notch1 in lung adenocarcinoma and lung squamous cell carcinoma. Biological pathways implicated by gene families were assessed using functional annotation tools (DAVID, ToppGene, and IPA). In vitro and in vivo knockdown studies assessed the functional role of Notch1.

Results: This novel co-expression analysis supports the hypothesis that NOTCH1 is co-expressed with different genes in lung adenocarcinoma and squamous cell carcinoma. Knockdown of Notch1 in vitro and in vivo support our in silico finding of opposing effects of NOTCH1. Our analysis implicates genes associated with metabolic pathways, immune pathways, angiogenesis and cell cycle that may underlie the differential role of NOTCH1 in lung adenocarcinoma and squamous cell carcinoma. In vitro and in vivo studies support our bioinformatics analysis.

Conclusion: These results demonstrate different NOTCH1 gene co-expression patterns in lung adenocarcinoma and squamous cell carcinoma. These findings provide novel insights underlying the context-dependent role of Notch as an oncogene and tumor suppressor in subtypes of lung cancer. Understanding the similarities and differences in co-expression patterns reveal novel insights, suggesting that tumor intrinsic and extrinsic pathways may underlie the dual role of NOTCH1 in lung cancer. Recognition of the mechanisms underlying NOTCH1 opposing roles in cancer may help direct development of Notch-targeted therapies as a monotherapy or in combination with approaches focusing on the tumor microenvironment.

Citation Format: Sara L. Sinicropi-Yao, David P. Carbone, Kevin R. Coombes, Joseph M. Amann, David Lopez Lopez. NOTCH1 co-expression analysis reveals novel insights underlying its opposing effects as an oncogenic and tumor suppressor in lung 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 545.
Abstract 5460: Discovery and evaluation of WX047, a potent and oral active phosphoinositide 3-kinase (PI3K)/mammalian target of rapamycin (mTOR) dual inhibitor
Authors: Li Ning , Guan Amy , Huang Lei , Hao Dongling , Gao Bo , Sun Jikui , Shih Nengyang , Kong Lingwei , Jiang Peipei , Li Yi , Yao Dan , Qin Yuxin , Yu Tao , Wu Chengde , Chen Shuhui , Yuan Hongyu , Lu Xiulian
Published: August 2018

Background: The PI3K/AKT/mTOR signaling pathway is important in regulating cell cycle, which is directly related to cellular quiescence, proliferation and longevity. Dysfunctional signaling of the PI3K/AKT/mTOR pathway in cancer, and its crucial role in cell growth and survival have made it a much desired target for cancer therapeutics.

Methods: By using structure-based design, the 4H-pyrido[1,2-a]pyrimidin-4-one derivative as an early lead was discovered. Further SAR studies optimized the in vitro and PK properties and led to the identification of WX047 as a potent dual inhibitor of PI3K and mTOR. Antitumor efficacy of WX047 was evaluated in the PC-3M xenograft tumor model.

Results: A series of 7-(pyridin-3-yl)-4H-pyrido[1,2-a]pyrimidin-4-one derivatives were synthesized and evaluated for in vitro and in vivo activities. Among them, WX047 was identified as a potent dual PI3K and mTOR inhibitor with IC50 for mTOR of 19.17 nM and IC50 for PI3Kα of 3.13 nM. The cellular activity of WX047 was determined in PC-3M cells by western blot analysis of p-Akt and p-70S6K with p-Akt and p-70S6K inhibition IC50 of 16 nM and 65 nM respectively. WX047 had low clearance and high oral bioavailability relative to those of the reference compound GSK2126458. In addition, WX047 also demonstrated significant antitumor efficacy in the PC-3M xenograft tumor models (79% TGI@10mpk, PO, QD).

Conclusions: WX047 has been identified as an orally active PI3K and mTOR dual inhibitor. It displays significant antitumor efficacy in the PC-3M xenograft tumor model. These support moving the compound forward to clinical investigation.

Citation Format: Ning Li, Amy Guan, Lei Huang, Dongling Hao, Bo Gao, Jikui Sun, Nengyang Shih, Lingwei Kong, Peipei Jiang, Yi Li, Dan Yao, Yuxin Qin, Tao Yu, Chengde Wu, Shuhui Chen, Hongyu Yuan, Xiulian Lu. Discovery and evaluation of WX047, a potent and oral active phosphoinositide 3-kinase (PI3K)/mammalian target of rapamycin (mTOR) dual inhibitor [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 5460.
Abstract 5470: IKK-epsilon supports anchorage independent growth via alternative NF-kB signaling in triple-negative breast cancer
Authors: House Carrie D. , Grajales Valentina , Ozaki Michelle , Jordan Elizabeth , Wubneh Helmae , Kimble Danielle , Kim Marianne , Annunziata Christina M.
Published: August 2018

Metastatic breast cancer carries a poor prognosis despite the success of newly targeted therapies and treatment options remain especially limited for the subtype of triple negative breast cancer (TNBC). Several signaling pathways, including NF-κB, are altered in TNBC. Given that ΙΚΚε behaves as an oncogene in breast cancer we hypothesized that IKKε regulates classical or alternative NF-κB signaling to control diverse oncogenic functions in TNBC. Vector expression and RNA interference were used to investigate the functional role of IKKε in triple-negative breast cancer cells. Viability, protein expression, NF-κB binding activity, invasion, anoikis, and spheroid formation were examined in cells expressing high or low levels of IKKε in conjunction with alternative NF-κB p52 RNA interference or MEK inhibition. Our data show that p52 protein levels and binding activity are inversely proportional to ΙΚΚε. Moreover, knockdown of IKKε leads to increased expression of p52 and the p52-regulated gene CXCL1. This interaction was confirmed by CHiP-PCR experiments showing increased binding of p52 in the CXCL1 promoter of cells with IKKε knockdown relative to control. We further found that IKKε and MEK were required for growth in anchorage supportive conditions whereas p52 was required in anchorage resistant conditions. Western blots confirm diminished IKKε expression and enhanced p52 processing in anchorage resistant conditions relative to anchorage supportive conditions. In this model, IKKε and MEK cooperate to support growth of cancer cells in the attached, anchored environment, whereas p52 is required for growth in unattached 3-D environment. These studies reveal novel information about the role of IKKε in TNBC and highlight the adaptability of NF-κB signaling in maintaining cancer cell survival under different growth conditions. Current studies are underway to clarify the mechanism of IKKε regulation of p52. A better understanding of the diversity of NF-κB signaling may ultimately improve the development of novel therapeutic regimens for TNBC.

Citation Format: Carrie D. House, Valentina Grajales, Michelle Ozaki, Elizabeth Jordan, Helmae Wubneh, Danielle Kimble, Marianne Kim, Christina M. Annunziata. IKK-epsilon supports anchorage independent growth via alternative NF-kB signaling in triple-negative 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 5470.
Abstract 5483: SIRT1 stabilization provides a therapeutic opportunity for reversing cachexia in pancreatic cancer
Authors: Dasgupta Aneesha , Vernucci Enza , Shukla Surendra K. , Mulder Scott E. , King Ryan J. , Abrego Jaime , Chaika Nina V. , Buettner Kyla , Singh Pankaj K. , Singh Pankaj K.
Published: August 2018

Cancer-associated cachexia is a complex metabolic syndrome which leads to excessive loss of skeletal muscle and adipose deposits. Up to 80% of pancreatic cancer patients suffer from cachexia and nearly one third die due to complexities related to the syndrome. Treatment of cachexia will not only improve the standard of living of pancreatic cancer patients but would also improve the patient survival. In the clinic, majority of the cancer patients are diagnosed at the refractory phase of cachexia, which cannot be reversed by dietary interventions. Till late therapies have not shown promising results in clinical trials. Hence, there is an urgent need to identify new targets to combat cancer cachexia. Sirtuins are protein deacetylases which affect the activity of various transcription factors and signaling components. The expression of all the sirtuins were analyzed after culturing mouse myotubes with tumor cell-conditioned media. The expression of SIRT1 decreased consistently upon treatment of myotubes with conditioned media from multiple human pancreatic cancer cell lines. Resveratrol, which is an activator of SIRT1 rescued the wasting phenotype in the myotubes. However, treatment of pancreatic cancer cells with resveratrol also decreased cell proliferation. Hence, we designed in vivo experiments to examine the effect of resveratrol on muscle wasting irrespective of its effects on tumor burden. We generated SIRT1 knockdown pancreatic cancer cell lines and orthotopically implanted them into the pancreas in athymic nude mice. The tumor-bearing mice were subjected to an oral delivery of resveratrol. These studies demonstrated that while resveratrol had limited effect on cancer cells due to SIRT1 knockdown, resveratrol treatment still protected the mice from muscle wasting by stabilizing SIRT1 in muscles. Hence, our results indicate that resveratrol-mediated stabilization of SIRT1 in muscles can revert wasting irrespective of its effects on tumor cells. Overall, our studies demonstrate the therapeutic potential of SIRT1 stabilization by resveratrol or related class of drugs in managing cancer-associated cachexia.

Citation Format: Aneesha Dasgupta, Enza Vernucci, Surendra K. Shukla, Scott E. Mulder, Ryan J. King, Jaime Abrego, Nina V. Chaika, Kyla Buettner, Pankaj K. Singh, Pankaj K. Singh. SIRT1 stabilization provides a therapeutic opportunity for reversing cachexia in pancreatic 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 5483.
Abstract 5498: Natural product-derived carbon nanodots overcome drug resistance through regulation of Hippo pathway effectors
Authors: Nurkesh Ayan A. , Balanay Mannix P. , Yeleusizov Tleubek , Tursynkhan Darkhan , Yang Qing , Wan Xiaoling , Manarbek Limara , Maipas Aisulu , Matkarimov Bakhyt , Zhang Yan , Fan Haiyan , Miao Li-Xia , Li Si-Pian , Chen Zhenbang , Xie Yingqiu
Published: August 2018

The yes-associated protein 1 (YAP) is a nuclear downstream effector of Hippo pathway that plays a critical role in various cancers. Literature shows that, in addition to nucleus, YAP also localizes in cytosol and membrane of cells. We and our collaborators previously reported that elevation of YAP associates with Arf in the genetically-engineered mouse (GEM) model of Pten/Trp53, implicating the possible correlation between Hippo/YAP and ARF in human cancers. We recently found ARF is indeed involved in dysregulation of Hippo pathway in prostate cancer. In details, ARF inhibited nuclear YAP translocation in cancer cells, and ARF knockdown suppressed the stability of YAP protein with upregulated active AKT and dysregulated phosphorylation of YAP through ARF/AKT/mTOR/YAP pathway. Here we further report that carbon nanodots (c-dots) can induce DNA damage through an increase of ROS by upregulation of γH2AX and DNA tails in PC3 and DU145 prostate cancer cells. We found that c-dots derived from natural products such as tea or beet can enter into cancer cell nucleus to interact with ARF for the regulation of the ARF-mediated signaling such as the nuclear translocation of YAP. Mechanistically, c-dots bind ARF to induce cell cycle arrest, apoptosis, and PARP cleavage in prostate cancer cells. Most importantly, addition of c-dots into cultured PC3 cells leads to the reversal of drug resistance to mTOR inhibitor Rapamycin and MET inhibitor Crizotinib by enhancing DNA damage. Moreover, c-dots suppress the tumor size and growth of PC3 cells in xenograft mouse model in vivo. Our data suggest that the nano-scale of c-dots derived from natural food may be efficient in overcoming drug resistance via augmentation of DNA damage linked cell death. Thus we reported a new approach of abolishing drug resistance of aggressive malignancy using nanoparticles, implicating an innovative avenue for precision cancer treatment.

Citation Format: Ayan A. Nurkesh, Mannix P. Balanay, Tleubek Yeleusizov, Darkhan Tursynkhan, Qing Yang, Xiaoling Wan, Limara Manarbek, Aisulu Maipas, Bakhyt Matkarimov, Yan Zhang, Haiyan Fan, Li-Xia Miao, Si-Pian Li, Zhenbang Chen, Yingqiu Xie. Natural product-derived carbon nanodots overcome drug resistance through regulation of Hippo pathway effectors [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 5498.
Abstract 5499: A potent BH3 mimetic targeting BCL-XL induces apoptosis regulated by PTEN loss and integrin alpha 5 in prostate cancer cells
Authors: Ren Wenying , Joshi Raghav , Mathew Paul
Published: August 2018

Background: PTEN-loss is a highly prevalent genomic event associated with higher risk of metastatic progression and resistance to hormonal therapy in prostate cancer. Akt inhibitor therapy in combination with abiraterone demonstrates early promise in the clinical control of PTEN-deficient prostate cancers. We have previously implicated BCL-XL in the survival of PTEN-null PC-3 prostate cancer cells in vitro, regulated by integrin alpha 5 (ITGA5) (Ren, MCR 2016). Toward advancing therapeutic strategies in PTEN-deficient prostate cancer we further assessed the link between PTEN and BCL-XL mediated prostate cancer cell survival.

Methods: Isogenic PTEN knockdown stable cell lines (VCAP and DU145) were generated by lentiviral transduction of pLKO-control-shRNA and two pLKO-PTEN-shRNAs, respectively. PTEN was exogenously expressed in PTEN-null prostate cancer cell lines (PC-3, LNCaP and C4-2B) by 1) transfecting cells with pCMV-Flag-vector or pCMV-Flag-PTEN 2) transfecting cells with pcDNA3-GFP-PTEN and then sorting GFP-PTEN-negative and GFP-PTEN-positive cells by flow cytometry. Cells were then treated with a single agent BCL-XL inhibitor (A1331852 or navitoclax (ABT263); AbbVie), PI3K (buparlisib; Selleck Chem) or Akt (ipatasertib, Selleck Chem) inhibitors or combined PI3K and BCL-2 family inhibitors. Cell survival was assessed by cell viability assay. Expression of pAkt, ITGA5 and apoptotic markers was assayed by Western blot analysis and/or flow cytometry.

Results: Notwithstanding the reduction of phospho-bad expression with PI3K inhibition, the potent BCL-XL-targeting BH3 mimetic, A1331852, compared to single agent PI3K or Akt inhibitors in titrated doses was alone sufficient to induce apoptosis and loss of cell viability in all PTEN-null prostate cancer lines tested. PTEN expression reversed the apoptotic response to BCL-XL targeting and blocked the anti-proliferative effect of PI3K or Akt inhibition in PTEN-mutant cells. PTEN knockdown induced membrane expression of ITGA5 whereas PTEN overexpression diminished ITGA5 expression.

Conclusions: PTEN regulates the apoptotic threshold in prostate cancer cells via BCL-XL independent of the PI3K/Akt pathway. The induction of ITGA5 membrane localization by PTEN loss defines a potential upstream signaling mechanism for the BCL-XL regulated apoptotic threshold in these cells. Highly potent BCL-XL inhibition requires further investigation as a therapeutic strategy in PTEN-deficient prostate cancer.

Citation Format: Wenying Ren, Raghav Joshi, Paul Mathew. A potent BH3 mimetic targeting BCL-XL induces apoptosis regulated by PTEN loss and integrin alpha 5 in prostate 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 5499.
Abstract 5500: Nitric oxide donor DETA/NO inhibits the growth of endometrial cancer cells by upregulating expression of RASSF1 and CDKN1
Authors: Taitz Hannah , Paucarmayta Ana , Cheng Robert , Maxwell George L. , Hamilton Chad A. , Wink David A. , Syed Viqar
Published: August 2018

Nitric oxide (NO), a small signaling molecule, is implicated in several biological processes including cancer progression. At low concentrations, it promotes cell survival and tumor progression, and at high concentrations it causes apoptosis and cell death. To date, the effects of NO donor on human endometrial cancer are largely unknown. Four endometrial cancer cell lines (Ishikawa, AN3CA, KLE and HEC-1B) with varying degrees of genetic complexity were treated with different concentrations (50-500 μM) of DETA/NO for 24 to 120 h. The effects of treatment on cell viability and invasion was determined using MTS, and Boyden chamber assays respectively. Treatment of endometrial cancer cells with DETA/NO induced a dose and time-dependent decrease in cell viability. Ishikawa and AN3CA cells were more responsive to DETA/NO induced growth inhibition compared to HEC-1B and KLE cells. Furthermore, DETA/NO effectively inhibited invasive potential of endometrial cancer cells. To understand the mechanisms by which DETA/NO elicits anti-cancer effects, RNA sequencing (RNA-seq) was used to ascertain alterations in the transcriptomes of human endometrial cancer cells. AN3CA, KLE, Ishikawa, and HEC-1B were treated with DETA/NO for 24 h and RNA was extracted. RNA-seq analysis revealed that of the twenty-one top differentially expressed genes, fourteen were upregulated and seven were downregulated in endometrial cancer cells with DETA/NO. The genes that were upregulated in all four cell lines with DETA/NO were tumor suppressors, RASSF1 and CDKN1A. The expression patterns of these genes were confirmed by Western blotting. Taken together, the results provide the first evidence in support of the anti-cancer effects of DETA/NO in endometrial cancer.

Citation Format: Hannah Taitz, Ana Paucarmayta, Robert Cheng, George L. Maxwell, Chad A. Hamilton, David A. Wink, Viqar Syed. Nitric oxide donor DETA/NO inhibits the growth of endometrial cancer cells by upregulating expression of RASSF1 and CDKN1 [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 5500.
Abstract 5507: RAG1 high expression associated with IKZF1 dysfunction in adult B-cell acute lymphoblastic leukemia
Authors: Ge zheng , Han Qi , Ma Jinlong , Gu Yan , Song Huihui , Kapadia Malika , Dovat Sinisa , Song Chunhua
Published: August 2018

The recombination activating gene (RAG)-mediated recombination is the dominant mutational process and the predominant driver of oncogenic genomic rearrangement in acute lymphoblastic leukemia (ALL). This then leads to further leukemic clonal evolution. IKZF1 encodes a kruppel-like zinc finger protein, IKAROS that is essential for normal hematopoiesis and acts as a tumor suppressor in ALL. The genetic defects of a single IKZF1 allele are linked to the development of human ALL, characterized by an increased risk of relapses and poorer prognosis. We observed that RAG1 is significantly increased in subsets of B-ALL patients. High RAG1 expression correlates with high proliferation markers. IKAROS directly binds to the RAG1 promoter in B-ALL cells by quantitative chromatin-immunoprecipitation assay. IKAROS suppresses RAG1 promoter activity by luciferase reporter assay. Lentiviral IKAROS expression significantly suppresses RAG1 expression, but IKAROS shRNA promotes RAG1 expression in B-ALL cells. CK2 inhibitor by restoring IKAROS activity, significantly suppresses RAG1 expression in an IKAROS-dependent manner in B-ALL cells. RAG1 expression is significantly higher in patients with IKZF1 deletion, as compared to patients without IKZF1 deletion. Treatment with CK2 inhibitor also results in an increase in IKZF1 binding to the RAG1 promoter and suppression of RAG1 expression in primary B-ALL cells. Taken together, our results demonstrate that high expression of RAG1 correlates with high proliferation markers in B-ALL, and are the first to demonstrate that IKAROS directly suppresses RAG1 expression. Our data suggest RAG1 high expression works together with IKAROS dysfunction to drive oncogenesis of B-ALL, which have significance in an integrated prognostic model for adult ALL.

Citation Format: zheng Ge, Qi Han, Jinlong Ma, Yan Gu, Huihui Song, Malika Kapadia, Sinisa Dovat, Chunhua Song. RAG1 high expression associated with IKZF1 dysfunction in adult B-cell acute lymphoblastic leukemia [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 5507.
Abstract 5518: Bi-allelic loss of CDKN2A initiates melanoma invasion and metastasis via E2F1-BRN2 axis
Authors: Zeng Hanlin , Jorapur Aparna , Shain A. Hunter , Lang Ursula E. , Torres Rodrigo , Zhang Yuntian , Botton Thomas , Lin Jue , Mcneal Andrew S. , Donne Matthew , Bastian Ingmar N. , North Jeffrey , Pincus Laura , Yu Richard , Ruben Beth S. , Joseph Nancy , Ye Iwei , Bastian Boris C. , Judson Robert L.
Published: August 2018

CDKN2A acts as a critical tumor suppressor in melanoma, as evidenced by frequent loss of function mutations and deletion. Loss of CDKN2A is believed to permit escape from senescent pre-neoplastic cell populations through relieve of a cell cycle block mediated by its two gene products. We performed a comprehensive analysis of CDKN2A gene status, mRNA and protein expression levels of p16 and p14 in a cohort of melanomas and their adjacent pre-neoplastic lesions and observed that bi-allelic CDKN2A loss coincides with the progression stage when primary melanomas become invasive. In melanoma lines, p16INK4A, one of the protein products of the CDKN2A locus, is a potent barrier to metastasis, independent of its known role inhibiting cell proliferation. We genetically engineered primary human melanocytes to harbor CDKN2A deletions and/or BRAF V600E mutation at their endogenous BRAF locus. Using this physiologic model for the early phases of neoplastic transformation, we found no evidence for BRAF-induced senescence, rather observing that p16INK4A loss activates a master regulator of melanoma invasion, BRN2, through Rb-E2F1 pathway. These results demonstrate that one of the most frequently altered genes across human cancers, CDKN2A, has an unexpected novel role in inhibiting cellular invasion through lineage specific transcription factors and acts as an essential gatekeeper of early metastatic dissemination.

Citation Format: Hanlin Zeng, Aparna Jorapur, A. Hunter Shain, Ursula E. Lang, Rodrigo Torres, Yuntian Zhang, Thomas Botton, Jue Lin, Andrew S. Mcneal, Matthew Donne, Ingmar N. Bastian, Jeffrey North, Laura Pincus, Richard Yu, Beth S. Ruben, Nancy Joseph, Iwei Ye, Boris C. Bastian, Robert L. Judson. Bi-allelic loss of CDKN2A initiates melanoma invasion and metastasis via E2F1-BRN2 axis [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 5518.
Abstract 5524: Tumor suppressor Numb represses monocarboxylate transporters to reduce the glycolysis in oral carcinoma
Authors: Chou Chung-Hsien , Chaing Chun-Yu Fan , Lin Shu-Chun , Chang Kuo-Wei , Tu Hsi-Feng
Published: August 2018

Oral squamous cell carcinoma (OSCC) is one of the most common malignancies worldwide. Our previous studies have shown that Numb pluripotent gene drives suppressor activity against OSCC, and it is co-targeted by multiple oncogenic miRNAs. In this study, we further identified that Numb mRNA expression was down-regulated in a large fraction of OSCC tumors. We established the Numb-knockout (KO) OSCC cell subclones using CRISPR-Cas9 system. We also generated lentiviruses for exogenous expression of Numb 1 and Numb 4 isoforms. The anchorage independent growth potential was found increased in Numb-KO cell subclones. However, such eligibility was repressed after the rescue of the Numb expression by lentiviral infection. In addition, the level of lactate production and the ratio of ECAR/OCR in the Numb-KO cell subclones were higher than parental cells. The knockout of Numb was able to up-regulate the expression of monocarboxylate transporter (MCT) family members MCT1 and MCT4, but not other metabolism genes, to increase the lactate production. Knockdown of both MCT1 and MCT4 significantly decreased the anchorage independent growth and the lactate production of OSCC cells. This study provides new evidences denoting that Numb represses MCTs to attenuate the transformative capability and the glycolysis in oral carcinoma.

Citation Format: Chung-Hsien Chou, Chun-Yu Fan Chaing, Shu-Chun Lin, Kuo-Wei Chang, Hsi-Feng Tu. Tumor suppressor Numb represses monocarboxylate transporters to reduce the glycolysis in oral 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 5524.
Abstract 5538: Arv7 validation in castrate resistant prostate tumors utilizing Rnascope in situ hybridization assay
Authors: Cash-Mason Tanesha , Wong Jackson , Martinez Martinez , Sharp Michael , Karkera Jayaprakash , Alvarez John D. , Chu Gerald C. , Thomas Shibu , Li Weiman , Tian S. Ken
Published: August 2018

Background

Androgen receptor splice variant 7 (ARV7) is a ligand-independent transcription factor associated with resistance to androgen deprivation therapy. There are efforts in development to monitor ARV7 expression during the treatment of patients with prostate cancer.

Methods

We evaluated ARV7 expression in primary and metastatic prostate adenocarcinomas tissues utilizing automated RNAScope (Advanced Cell Diagnostics) ISH assay, Immunohistochemistry (IHC) and quantitative PCR (qPCR). The novel RNAscope ISH assay was used for direct chromogenic visualization of RNA transcripts and to confirm positivity as an orthogonal approach to validate IHC and quantitative qPCR assay findings. We screened a total of 44 CRPC FFPE tumor samples by IHC and a subset of 28 (excluding controls) with the ISH and qPCR assays. Samples for qPCR were enriched for tumor by macrodissection. RNAScope Scoring Criteria was used to score ISH expression and raw Ct values were normalized to the RPL19 housekeeping gene for qPCR. Thresholds for each assay was established by comparing the findings with the other 2 assays. The data was calculated as ARV7 (+) or ARV7 (-) based on thresholds and compared to the other 2 assays to establish assay performance statistics.

Results

The ISH screening of 28 CRPC tumors resulted in 16 tumors with some level of positivity and approximately 10 tumors with significant positivity. Of the 44 CRPC tumors stained by IHC, 16 tumors showed various levels of ARV7 nuclear positivity and 8 tumors with strong positivity.

Conclusions

The detection of ARV7 was achieved in three independent assays. The correlation of three orthogonal data sets were used to identify positive and negative tissues. ISH has the potential for greater sensitivity compared to traditional IHC. The development of automated RNAscope ISH assay allows for more samples to run in a standardized manner with minimal inter-operator variably and requires less hands on-time gives consistently reproducible results.

Citation Format: Tanesha Cash-Mason, Jackson Wong, Martinez Martinez, Michael Sharp, Jayaprakash Karkera, John D. Alvarez, Gerald C. Chu, Shibu Thomas, Weiman Li, S. Ken Tian. Arv7 validation in castrate resistant prostate tumors utilizing Rnascope in situ hybridization assay [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 5538.