bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 1796: p53 regulation of osteoblast differentiation is mediated through specific microRNAs
Authors: Pendleton Elisha , Shah Shivang , Couture Oliver , Kusper Teresa , Broachwalla Mustafa , Alt Lauren , Fay Michael , Chandar Nalini
Published: August 2019

We have previously shown a role for tumor suppressor gene p53 in the transcriptional activation of several bone-specific genes in osteoblast differentiation. In this study, we used a screen for microRNAs to look for ones that were p53 dependent and differentiation dependent. In a model of invitro osteoblast differentiation, our previous work has established that p53 levels generally increase around day 4 of differentiation and represent the timeline when p53 transcriptionally regulates bone-specific gene expression. In these experiments, we used MC3T3-E1 osteoblasts to stably reduced p53 levels using specific shRNAs. These cells were initially characterized for the reduction in p53 levels and then compared with MC3T3E1 cells stably transfected with a scrambled control (Control MC3T3E1 cells). MicroRNAs were isolated from day 0 and day 4 after treatment with differentiation promoting (DP) media. A microRNA profiling service utilizing a microarray detection system analyzed over 1000 different microRNAs in control and DP treated cells to determine differentiation specific microRNAs expression. This array provided us with information about a number of genes that underwent alterations during differentiation in a p53 dependent manner. We validated several of the changes using realtime PCR and selected two microRNAs to study in detail. These two microRNAs (mIR 34b and 140) were increased two fold during normal differentiation but showed a dramatic reduction in expression when p53 levels were reduced. We ectopically expressed these microRNAs in MC3T3-E1 cells and created stable lines. Cells carrying mIR34b showed a decrease in cell proliferation rates when compared to mIR140 expressing and control cells. P53 levels directly correlated with microRNA 34b expression but not mIR140. MiR 140 ectopic expression affected Bone morphogenetic protein expression (BMP2), an important bone anabolic agent that is also p53 regulated. Putative target binding sites for bone-specific transcription factors Runx2, SP7, Vitamin D receptor (VDR) were found for mIR34b and 140 and were utilized in luciferase reporter assays to confirm microRNA specific interactions. These studies provided evidence and confirmed for us that the p53 regulation of osteoblast differentiation is also mediated through specific microRNAs that directly target important bone-specific genes.

Citation Format: Elisha Pendleton, Shivang Shah, Oliver Couture, Teresa Kusper, Mustafa Broachwalla, Lauren Alt, Michael Fay, Nalini Chandar. p53 regulation of osteoblast differentiation is mediated through specific microRNAs [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1796.
Abstract 1797: Serum microRNAs as immune modulators and biomarkers of breast cancer recurrence
Authors: Chen Lauren , Soni Mithil
Published: August 2019

MicroRNAs (microRNAs) are short sequences of RNA (about 22 nucleotides) that are involved in the regulation of gene expression. Previous studies have suggested that a number of microRNAs are recognized as new biomarkers for cancers. The aim of this study is to identify specific microRNAs in serum, which may serve as potential diagnostic and prognostic biomarkers and therapeutic targets for breast cancer. Quantitative real-time PCR (qRT-PCR) array analyses of microRNAs in sera from four pairs of recurrent and nonrecurrent breast cancer patients were performed. Those differentially expressed microRNAs were verified in serum samples from 42 breast cancer patients. The prognostic values of the selected microRNAs were statistically analyzed, determined by the correlation between microRNA expression and tumor parameters. High serum levels of miR-134 and miR-483-5p were found to be associated with some aggressive tumor behaviors. Kaplan-Meier analysis of four upregulated microRNAs (miR-134, miR-483-5p, miR-493-3p and miR-139-3p) indicated that serum level of miR-134 can predict tumor recurrence in breast cancer patients after primary treatment. Further functional analysis showed that overexpression of miR-134 has no significant effects on tumor growth but regulates macrophage M1/M2 polarization. Overall, our data suggested that serum microRNAs may promote tumor progression and recurrence via modulating inflammation and immune response and potentially serve as blood biomarkers for prediction of recurrence in breast cancer.

Note: This abstract was not presented at the meeting.

Citation Format: Lauren Chen, Mithil Soni. Serum microRNAs as immune modulators and biomarkers of breast cancer recurrence [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1797.
Abstract 18: Doubled lifespan in APCMin/+ mice by targeting MTAP
Authors: Firestone Ross S. , Feng Mu , Schramm Vern L.
Published: August 2019

Humans with Familial Adenomatous Polyposis (FAP) have increased risk of colon cancer. Mice with the APCMin/+ mutation provide an animal model of FAP. Interruption of epigenetic control by preventing salvage of S-adenosylmethionine from 5′-methylthioadenosine (MTA) was tested as a potential FAP therapy. 5′-Methylthioadenosine phosphorylase (MTAP) catalyzes the phosphorolysis of MTA to adenine and methylthioribose-1-phosphate for methionine recycling. The effect of MTDIA, a transition state analogue of MTAP, was tested as an oral agent in APCMin/+ mice. Survival analysis with 10, 20 and 30 mg/kg/day oral doses of MTDIA showed a 2-fold increase in mouse lifespan at the optimal 20 mg/kg/day dose. Metabolomic analysis (mouse liver) showed significant changes in metabolites relevant to methionine metabolism. The >4-fold increase in MTA, confirmed the physiologic target. Histologic analysis of intestinal tissue revealed slowed tumor progression in treated mice. RNAseq and Western blots provide additional information about the consequences of MTAP inhibition.

Citation Format: Ross S. Firestone, Mu Feng, Vern L. Schramm. Doubled lifespan in APCMin/+ mice by targeting MTAP [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 18.
Abstract 180: Defining the metastasome in colorectal cancer: Novel hypotheses on tumor progression, metastasis evolution and therapy by whole genome sequencing
Authors: Allgayer Heike
Published: August 2019

Metastasis poses the highest challenge for personalized therapy, partly due to incomplete understanding of its molecular evolution. This work presents the most comprehensive whole-genome study of colorectal metastasis vs. matched primary tumors. The cohort presented supports both early and late dissemination models. 65% of somatic small mutations originated from a common ancestral truncal node, with 15% of small mutations being tumor- and 19% metastasis-specific, implicating a higher mutation rate in metastases. In tumor- and metastasis-specific mutations we observed elevated levels of BRCA-ness signatures. A multistage progression model was confirmed with new components ARHGEF7/ARHGEF33, and ploidy dependent co-occurring SOX9 and HK3 mutations. We found previously undescibed recurrently mutated non-coding elements including specific ncRNAs and 3’ UTRs which will be presented at the meeting, some of them known as potential dual protagonists in metastasis and efferocytosis-/PD-L1 mediated immunosuppression. Furthermore, we discovered genomic aberrations explaining microRNA expression changes during metastasis. Moreover, we found actionable metastasis-specific lesions (which will be reported at the meeting) which would not have been detected in whole genome sequencing of the corresponding primary tumor, suggesting a reconsideration and modifications of current personalized therapy concepts to prevent metastasis. Metastasis-specific small mutations were enriched in PI3K-Akt signaling, cell adhesion, extracellular matrix but also hepatic stellate activation pathway genes, suggesting the initiation of genetic programs for site-specific colonization during metastasis. Taken together, the results presented here reveal novel components of disease progression and metastasis evolution with evidence for metastasis-specific genomic lesions relevant for personalized therapy.

Citation Format: Heike Allgayer. Defining the metastasome in colorectal cancer: Novel hypotheses on tumor progression, metastasis evolution and therapy by whole genome sequencing [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 180.
Abstract 1810: LncCGU1 and AFP serve as important prognostic marker in non-hepatitis B non-hepatitis C hepatocellular carcinoma
Authors: Lin Kwang-Huei , Lin Yang-Hsiang , Liu Yu-Chin
Published: August 2019

Background: Thyroid hormone (T3) and its receptor (TR) are involved in cell metabolism and cancer progression. Hypothyroidism is a significantly elevated risk factor for hepatocellular carcinoma (HCC). Alpha-fetoprotein (AFP) is increased in the majority of patients with HCC and may be useful in the diagnosis and follow-up of cases of HCC. The relationship between T3/TR and AFP levels in HCC is still unclear. Design: We used microarrays to compare expression profiles of lncRNAs in HepG2-TRα1 cells treated with/without T3 and HCC specimens. The profiling results were validated using qRT-PCR. The overall survival and recurrence-free survival were analyzed using Kaplan-Meier method and further confirmed by online available datasets. Results: In the current study, long non-coding RNA CGU1 was downregulated by T3/TR in vitro. Notably, α-fetoprotein (AFP) mRNA levels were downregulated by T3/TR through repression of CGU1. Notably, AFP mRNA is strongly positively correlated with CGU1 and unfavorable prognosis in non-hepatitis B/non-hepatitis C HCC (NBNC-HCC) group patients. Conclusions: our data collectively suggest that T3/TR/ CGU1/AFP act as a potential prognostic marker in NBNC-HCC.

Citation Format: Kwang-Huei Lin, Yang-Hsiang Lin, Yu-Chin Liu. LncCGU1 and AFP serve as important prognostic marker in non-hepatitis B non-hepatitis C hepatocellular carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1810.
Abstract 1811: The long noncoding RNA KIAA0125 is aberrantly expressed in ameloblastomas
Authors: Sousa Silvia F. , Diniz Marina G. , França Josiane A. , Vilas-Boas Fabricio A. , Souza Fabricio T. , Calin George A. , Gomez Ricardo S. , Gomes Carolina C.
Published: August 2019

Long noncoding RNAs (lncRNAs) are transcribed RNA molecules that can interact with DNA or RNA, transcription factors, histones and other chromatin modifying proteins, affecting the expression level of a broad spectrum of genes. Because of their tissue-specific expression characteristics, lncRNAs hold strong promise as novel biomarkers and therapeutic targets for diseases. High-density whole-genome microarray analysis in ameloblastomas, an aggressive odontogenic tumor, and in adenomatoid odontogenic tumor (AOT), an indolent one, showed a high frequency of copy number alteration at chromosome band 14q32.33, which encompasses the lncRNA gene KIAA0125. To understand molecular mechanisms associated with their biological behavior and considering the copy-number gains observed at 14q32.33, we aimed to investigate the expression levels of the lncRNA KIAA0125 in ameloblastomas and in AOTs. The University Ethics Committee approved this study and patients signed informed consent. Thirteen frozen samples were included: five solid/multicystic ameloblastomas, four AOT, and four dental follicles. qPCR reactions were performed in triplicates and the relative changes in gene expression were obtained using the 2^-ΔΔCt formula. The reference gene HPRT1 was used for normalization and the human keratinocyte HaCat cell line was used as calibrator. Differences in the relative changes in gene expression between two groups of samples were assessed and the significance level was set at 0.05. All samples expressed more KIAA0125 than the calibrator. The ameloblastoma group showed higher expression levels of KIAA0125 when compared to dental follicles (p=0.042), while there was no difference between the expression in ameloblastomas and AOT (p>0.05). The expression levels of KIAA0125 in AOT were not different from that of the dental follicle. Our findings suggest that lncRNA KIAA0125 is likely involved in ameloblastoma pathobiology. LncRNAs hold strong promise as therapeutic targets, and experimental validation of this lncRNA functions may lead to tailored therapies targeting KIAA0125 in extensive and recurrent ameloblastomas.

Citation Format: Silvia F. Sousa, Marina G. Diniz, Josiane A. França, Fabricio A. Vilas-Boas, Fabricio T. Souza, George A. Calin, Ricardo S. Gomez, Carolina C. Gomes. The long noncoding RNA KIAA0125 is aberrantly expressed in ameloblastomas [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1811.
Abstract 1814: Carboxyl-terminal truncated HBx represses lncRNA-LOC to promote cell metastasis
Authors: Lin Yang Hsiang , Yeh Chau-Ting , Lin Kwang-Huei
Published: August 2019

Hepatocellular carcinoma (HCC) is one of the most common and aggressive human malignancy in the world. The poor prognosis of HCC is partly due to a high incidence rate of extrahepatic metastases. Several studies have shown that the relative risk of HCC among hepatitis B virus (HBV) carrier is higher than non-carrier group. Among the four proteins translated by HBV, X-gene (HBx) has been correlated with oncogenesis of HCC. Meanwhile, it is well known that random HBV genome integration can cause truncation of the HBV genome, especially on the HBx gene locus at the C-terminus (designated as Ct-HBx). The discovery of long non-coding RNA (lncRNA) transcripts has dramatically expanded our understanding of cell biology, especially in cancer. However, the underlying molecular mechanisms of lncRNAs that mediate the metastatic cascade and cancer progression remain largely unclear in liver cancer. In this study, lncRNA-LOC is significantly downregulated in HCC and negatively correlated with overall survival in HCC patients. LncRNA-LOC is negatively regulated by Ct-HBx in vitro and in vivo (HCC specimens). Two novel transcripts of LncRNA-LOC in HepG2 and Huh7 cell lines were identified by 5’ and 3’ rapid amplification of cDNA ends assays, respectively. Overexpression of lncRNA-LOC induced marked inhibition of cell migration, invasion and cell proliferation in vitro. On the other hand, these phenotypes were reversed upon knockdown of lncRNA-LOC in cells. Mechanically, levels of p-STAT3 (Tyr705 and Ser727), p-c-Jun (Ser63) and Snail were decreased in lncRNA-LOC-overexpressing cells, compared to control cells. Our data collectively highlight that novel regulatory associations among lncRNA-LOC, Ct-HBx, p-STAT3, p-c-Jun and Snail are an important determinant of metastasis in HCC cells and support the potential utility of lncRNA-LOC as a therapeutic strategy for HCC.

Citation Format: Yang Hsiang Lin, Chau-Ting Yeh, Kwang-Huei Lin. Carboxyl-terminal truncated HBx represses lncRNA-LOC to promote cell metastasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1814.
Abstract 181A: PIN1 and FOXP3 regulate SKP2 expression
Authors: Yang Wei-Hsiung , Wang Chiung-Min , Yang William H.
Published: August 2019

S-phase kinase-associated protein 2 (SKP2), a component of the E3 ubiquitin ligase SKP1-CUL1-Fbox complex, acts as an oncogene/oncoprotein as evidence suggests that overexpression of SKP2 results in cell cycle dysregulation and tumorigenesis as well as associates with poor prognosis in numerous cancers. The unique peptidyl-propyl isomerase PIN1, which isomerizes the cis-trans peptide bond between pSer/pThr and proline, regulates its target proteins’ cell localization, stability, and function. However, whether SKP2 is the target protein of PIN1 remains unknown. Herein, we demonstrate that SKP2 expression is regulated by PIN1 and FOXP3. First, we observed that knock-down PIN1 using siRNAs reduced SKP2 protein level in several cancer cell lines (MCF7, PC3, DU145, HepG2, and JEG3 cells). Secondly, we found that overexpression of PIN1 increased SKP2 protein level. Furthermore, PIN1 dose-dependently enhanced SKP2 promoter activity in gene reporter assay. Since FOXP3 is a known transcriptional repressor for the oncogene SKP2, we investigated whether PIN1 affects FOXP3-mediated SKP2 expression. Interestingly, we observed that PIN1 dose-dependently counteracted FOXP3-mediated SKP2 promoter activity. Finally, we demonstrated that mutations on PIN1 (W34A) and FOXP3 (Y342F) abolished PIN1-mediated and FOXP3-mediated SKP2 expression, respectively. Taken together, our results suggest that PIN1 functions as a novel regulator of SKP2 and with FOXP3 may be involved in tumor development and progression.

Citation Format: Wei-Hsiung Yang, Chiung-Min Wang, William H. Yang. PIN1 and FOXP3 regulate SKP2 expression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 181A.
Abstract 182: Cancer stem cells and tumor angiogenesis in serous adenocarcinoma of ovary
Authors: Krishnapriya S , Sidhanth C , Manasa P , Sneha S , Bindhya S , Nagare R P. , Ganesan T S.
Published: August 2019

The traditional view of tumour vascularization is that tumours acquire blood supply from the neighbouring normal stroma. However, recently the origin of tumour endothelial cells or pericytes in part has been shown to be derived from cancer stem cells (CSCs) in glioblastoma. In high grade serous ovarian cancer (HGSOC), the origin of endothelial cells is not known. Our objective was to determine if components of a tumour blood vessel and lymphatic vessel are derived from CSCs in ovarian cancer. Using spheroids as an in vitro model, we have evaluated the role of CSCs in primary malignant cells (PMCs) from patients with serous adenocarcinoma of ovary cultured under specific conditions. The expression of endothelial, pericyte and lymphatic endothelial markers was evaluated by flow cytometry. In addition, functional assays were performed to assess the endothelial phenotype. Further, the ability of CSCs to express endothelial markers under appropriate growth conditions was also evaluated with Bevacizumab which antagonize VEGF. PMCs grown in endothelial growth medium (EGM) showed significantly higher expression of CD105 (n=32, p = 0.002) and CLEC14A (n=10, p = 0.012) and co-expression of CD105/CLEC14A (n=10, p= 0.012) than that of spheroids. Primary malignant cells when grown in pericyte and lymphatic endothelial specific conditions, showed significantly higher expression of desmin (n=10, p=0.03), Smooth muscle actin (SMA) (n=10, p=0.017) and VEGFR3 (n=10, p=0.028) than that of the spheroids. When the PMCs were grown as spheroids in endothelial conditions in the presence or absence of Bevacizumab (1 μg/μl), there was a reduction in the co-expression of CD105 and CLEC14A (P=0.04). The cells grown in endothelial conditions showed formation of tubes, uptake of Dil-ac-LDL and expressed eNOS, confirming their endothelial phenotype. GFP transduced spheroids from PMCs formed tumours in mice and the blood vessels in the tumour co-expressed CD31, SMA, VEGFR3 and GFP, suggesting that these cells are derived from CSCs. These results prove that a proportion of endothelial cells, pericytes and lymphatic endothelial cells are derived from CSCs in serous ovarian carcinoma and the VEGF pathway has a key role. This property of CSCs to contribute to tumour angiogenesis can be inhibited.

Citation Format: S Krishnapriya, C Sidhanth, P Manasa, S Sneha, S Bindhya, R P. Nagare, T S. Ganesan. Cancer stem cells and tumor angiogenesis in serous adenocarcinoma of ovary [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 182.
Abstract 1825: Epithelial adherens junctions suppress the pro-tumorigenic MIR17HG lncRNA by recruiting RISC
Authors: Bridges Mary C. , Nair-Menon Joyce , Kourtidis Antonis
Published: August 2019

The adherens junctions (AJs) are essential architectural elements of epithelial tissues. Compromised junctional integrity is a common precursor to colon cancer. Recently, we identified a novel mechanism whereby the AJs of non-transformed colon cells recruit the microprocessor and RISC, core elements of the RNAi machinery, as well as miRNAs, to suppress oncogenic mRNAs. Knockdown of the AJ component PLEKHA7, disrupts this RNAi-mediated signaling program, leading to pro-tumorigenic cell transformation. Interestingly, PLEKHA7 RNA-CLIP and subsequent RNA-Seq analysis identified association with numerous long non-coding RNAs (lncRNAs). While a number of lncRNAs have been associated with tumorigenesis, the underlying mechanisms of their regulation during tumor progression are still unclear. As lncRNAs can interact with the RNAi machinery, we hypothesize that the AJs regulate lncRNAs via this localized RNAi mechanism. Examination of PLEKHA7-depleted cells by RNA-seq revealed differential expression of 49 junction-associated lncRNAs. From this set, the top upregulated lncRNA is MIR17HG, an oncogenic polycistronic host transcript of the miR-17-92 cluster. Junctional localization of MIR17HG was confirmed by RNA-FISH. Adherens junctions destabilization by E-cadherin knockdown also led to the upregulation of MIR17HG, demonstrating the role of junctional integrity in MIR17HG suppression. Data from Ago2 knockdown, anti-miR, and miRNA mimic experiments show that PLEKHA7 suppresses the levels of the MIR17HG transcript through the junction-associated RISC and two miRNAs, miR-203a and miR-372. PLEKHA7 depletion also results in increased levels of a subset of MIR17HG hosted miRNAs, including miR-19a and miR-19b, both known cancer promoters. Ectopic expression of PLEKHA7 in the aggressive HCT116 colon cancer cells that lack endogenous PLEKHA7 expression, suppressed anchorage independent growth, as well as MIR17HG levels, which are elevated in these cells. We are currently examining the role of MIR17HG as a functional intermediate of PLEKHA7’s loss on colon cell transformation. In summary, our data point towards a novel mechanism of lncRNA regulation that tethers epithelial architecture with cell behavior.

Note: This abstract was not presented at the meeting.

Citation Format: Mary C. Bridges, Joyce Nair-Menon, Antonis Kourtidis. Epithelial adherens junctions suppress the pro-tumorigenic MIR17HG lncRNA by recruiting RISC [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1825.
Abstract 1828: Genetic profiling of breast cancer confirms a pivotal role of EGFR pathway in the development of acquired resistance to tamoxifen
Authors: Bahnnasy Abeer A. , Malash Ibrahim , Al-Lahlouby Nasr , Mansour Osman , Shaarawy Sabry , Abdellateif Mona S. , Yousef Hend , Lotfy Mai M. , Gaafar Rabab , elsesy Mohamed. , Zekri Abdel-Rahman N.
Published: August 2019

Background: Metastatic breast cancer (MBC) represents a major health problem in Egypt and worldwide. Prognostic and predictive factors for patients with MBC are highly needed, for better management and improved survival. The aim of this study was to assess the prognostic and predictive value(s) of CYP2D6 polymorphisms in MBC patients on Tamoxifen and to determine the genetic profile(s) of Tamoxifen responders and non-responders. Methods: We assessed 157 females with hormone receptor positive, locally recurrent inoperable and/or metastatic breast cancer (MBC) patients from Egypt for 1) CYP2D6 polymorphisms and 2) genetic aberrations in the EGFR pathway (92 genes). All patients received Tamoxifen and according to their response they were divided into Tamoxifen-responders and refractory. RNA was extracted from tumor and normal tissue samples and used to assess the genetic profiles of the patients using the SABioscience array (Qiagen) with four house-keeping genes. Results: 92(58.6%) patients were ER and PR positive, 51 (32.5%) were ER positive and 14 (8.9%) were PR positive. CYP2D6 *3/*4 was significantly prevalent in the refractory group (86.6%).Variants *10/*10 and *10/*3 were more common in the responders (85.5%) compared to refractory (P=0.027). CYP2D6 polymorphism associated significantly with Her-2 amplification (P<0.001), and reduced overall survival rate of patients in both refractory and responder groups (P< 0.001). Fifty-six genes were differentially over-expressed in the refractory group compared to responders, of which only JAK1, COL1A1, GAB1, FN1and MKNK1 showed a significant difference. In the refractory group 34 genes were differentially reduced compared to responders; none of them showed significant difference. Response to Tamoxifen associated significantly with disease site since patients with bone only disease showed better response than those with visceral metastases (P<0.005). Conclusion: A panel of 5 genes in EGFR pathway (MJAK1, COL1A1, GAB1, FN1 and MKNK1) together with CYP2D6 polymorphism scan predict response to Tamoxifen in metastatic BC patients though this has to be verified in an extended study including larger sample.

Citation Format: Abeer A. Bahnnasy, Ibrahim Malash, Nasr Al-Lahlouby, Osman Mansour, Sabry Shaarawy, Mona S. Abdellateif, Hend Yousef, Mai M. Lotfy, Rabab Gaafar, Mohamed. elsesy, Abdel-Rahman N. Zekri. Genetic profiling of breast cancer confirms a pivotal role of EGFR pathway in the development of acquired resistance to tamoxifen [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1828.
Abstract 1829: HSF1 suppresses AMPK to promote lipogenesis, cholesterol biosynthesis and protein lipidation
Authors: Su Kuo-Hui , Dai Chengkai
Published: August 2019

AMP-activated protein kinase (AMPK), a key cellular metabolic sensor, suppresses anabolic pathways, including lipogenesis and cholesterol biosynthesis, thereby maintaining energy homeostasis. Heat shock factor 1 (HSF1) is the master regulator of the evolutionarily conserved proteotoxic stress response (PSR), thereby preserving proteostasis in the face of environmental insults. In contrast to its beneficial role in enhancing survival under proteotoxic stress, it has been demonstrated that HSF1 acts as a potent pro-oncogenic factor. Our previous study has shown that metabolic stressors, via AMPK activation, inactivate HSF1 and disrupt proteostasis to suppress tumor growth. Interestingly, our new study now reveals that HSF1, in reciprocal, also suppresses AMPK activation. HSF1 does so independently of its canonical transcriptional action. Furthermore, Hsf1 deficiency promotes the interactions between AMPK and LKB1, a key upstream kinase activating AMPK. Congruent with the suppression of lipogenesis by AMPK, Hsf1 deficiency depletes cellular lipid content and reduces body fat mass in mice. Importantly, these defects can be largely rescued by either pharmacological or genetic inhibition of AMPK. At the molecular level, Hsf1 deficiency leads to inactivation of acetyl-CoA Carboxylase (ACC) and sterol regulatory element-binding transcription factor 1c (SREBP1c), both of which are key players in de novo lipogenesis. In addition to impaired lipogenesis, Hsf1-deficient cells and mice display reduced cholesterol levels. Of particular interest, this defect leads to impaired cholesteroylation of sonic hedgehog (SHH), the best known signaling molecule undergoing this covalent modification. In consequence, SHH secreted by HSF1-deficient cells are less potent in activating its downstream signaling cascade, indicated by reduced DNA binding of GLI1, a transcription factor responding to activation of SHH signaling. Conversely, HSF1 overexpression increases the lipid content, cholesterol levels and the amount of cholesteroylated SHH proteins in xenografted melanomas. Taken together, our results reveal that HSF1, through AMPK suppression, promotes lipogenesis, cholesterol biosynthesis and protein lipidation, thereby supporting malignant growth.

Citation Format: Kuo-Hui Su, Chengkai Dai. HSF1 suppresses AMPK to promote lipogenesis, cholesterol biosynthesis and protein lipidation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1829.
Abstract 185: Direct cytotoxic effect of a novel anti-angiogenic drug F16 towards U87MG glioblastoma cell line
Authors: Algahtani Mohammad , Alhazzani Khalid , Venkatesan Thiagarajan , Alaseem Ali , Dhandayuthapani Sivanesan , Rathinavelu Appu
Published: August 2019

Glioblastoma multiforme (GBM) is one of the most aggressive and lethal types of brain cancers with low 5-year survival rate. Therefore, search for better drugs and effective treatment strategies for GBM to improve patient outcomes is continuing. Since GBM is one of the most highly vascularized solid tumors and its growth is angiogenesis-dependent, antagonizing tumor angiogenesis by using angiogenesis inhibitors seems to be one of the promising approaches. In this context, intensive pre-clinical evaluation of our patented anti-angiogenic compound, code-named F16, has exhibited potent anti-angiogenic and anti-tumor activities via selectively antagonizing VEGFR-2 in both in vitro and in vivo models. More importantly, assessment of biochemical parameters that are reflecting the safety of F16 in the in vivo system showed no alterations in the toxicological parameters of heart, liver, kidney, and pancreas, after 30 days of treatment, at the dose of 100 mg/kg body weight. Hence, we tested the direct effects of F16 for inhibiting the growth, angiogenesis and the migratory abilities of the U87MG glioblastoma cells, which are known to express high levels of VEGFR. Our in vitro studies have confirmed potent inhibitory effects of F16 towards the migration and invasion of U87MG cells, and also revealed potent cytotoxic effects (IC50 26 µM) against U87MG cells in comparison to Temozolomide (IC50 430 µM) treatment. In addition, F16 inhibited the phosphorylation of VEGFR-2 through competitive binding and also induced cell cycle arrest and apoptosis by activating p53 pathway in U87MG cells. Furthermore, our in vivo results with ectopically implanted xenograft model confirm the fact that F16 can significantly inhibit tumor growth in the mice implanted with U87MG glioblastoma cell line. Based on our preliminary results, we are proposing that F16 could be a potential candidate for treating GBM, either in monotherapy or in combination with a cytoreductive drug. (This research was supported by the generous funds provided by the Community Foundation of Broward, Florida and also by the Royal Dames of Cancer Research Inc., Ft. Lauderdale, Florida)

Citation Format: Mohammad Algahtani, Khalid Alhazzani, Thiagarajan Venkatesan, Ali Alaseem, Sivanesan Dhandayuthapani, Appu Rathinavelu. Direct cytotoxic effect of a novel anti-angiogenic drug F16 towards U87MG glioblastoma cell line [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 185.
Abstract 1850: Role of microRNAs in circulating tumor cells glutamine metabolism pathways
Authors: Zhu Ziwen , Owen Sarah N. , Achreja Abhinav , Nagrath Sunitha , Nagrath Deepak
Published: August 2019

Circulating tumor cells (CTCs) has an important role in the spread of cancers and metastasis. CTCs are believed to be the most promising model to understand metastatic progression in patients with cancer. Glutamine, an alternative carbon source to glucose, has recently been shown to be important for the cancer cell survival, growth and progression. The role of glutamine metabolism in CTCs is not known. MicroRNAs (miRNAs) are a group of highly conserved noncoding RNAs and approximately 22 nucleotides in length. Here, we postulate that CTCs have unique microRNAs (miRNAs) expression compared to resident tumor cells. And miRNAs control CTC glutamine metabolism for the metastasis. In this study, we used 3 primary CTC cultures to study how miRNA controlling glutamine metabolism. We identified several miRNAs have high expressions in CTCs and these miRNAs are regulating glutamine metabolism in CTCs. Our results demonstrate the metabolic miRNA targets of CTCs on cancer progression. These insights will present a unique opportunity for diagnosing and treating cancer through CTCs.

Note: This abstract was not presented at the meeting.

Citation Format: Ziwen Zhu, Sarah N. Owen, Abhinav Achreja, Sunitha Nagrath, Deepak Nagrath. Role of microRNAs in circulating tumor cells glutamine metabolism pathways [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1850.
Abstract 1851: Novel roles of DNA-PK in metabolic regulation in prostate cancer
Authors: Dylgjeri Emanuela , Goodwin Jonathan , Shafi Ayesha , Kothari Vishal , Zadra Giorgia , Seifert Erin , Feng Felix , Knudsen Karen
Published: August 2019

DNA dependent protein kinase catalytic subunit (DNA-PK) is a multifunctional kinase involved in repairing double-strand DNA breaks through non-homologous end joining (NHEJ), with parallel roles as a master transcriptional regulator of gene networks supporting cell migration and invasion. In prostate cancer (PCa), DNA-PK was found to be highly upregulated and hyperactivated. Strikingly, DNA-PK is the most deregulated kinase in metastatic castration resistant prostate cancer (CRPC), and is independently predictive of metastasis and overall survival in patients with high-risk disease. Combined, these findings highlight the importance of understanding DNA-PK functions beyond DNA repair and transcriptional regulation, which promote the acquisition of aggressive tumor phenotypes. Rapid immunoprecipitation of endogenous proteins (RIME) was performed to identify the DNA-PK interactome, which uncovered novel DNA-PK interactors that play key roles in metabolism. To assess the role of DNA-PK in regulation of metabolism, metabolic profiles of CRPC models were investigated upon DNA-PK modulation. Data presented will describe novel roles of DNA-PK in cancer metabolism and subsequent effects of DNA-PK modulation in key metabolic pathways.

Citation Format: Emanuela Dylgjeri, Jonathan Goodwin, Ayesha Shafi, Vishal Kothari, Giorgia Zadra, Erin Seifert, Felix Feng, Karen Knudsen. Novel roles of DNA-PK in metabolic regulation in prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1851.
Abstract 1852: Down-regulation of PRMT6 drives Warburg effect through ERK induced relocalization of PKM2 to promote tumorigenicity and sorafenib resistance in hepatocellular carcinoma
Authors: Wong Tin-Lok , Chan Lok-Hei , Ma Stephanie
Published: August 2019

Cancer cells have a high dependence of glycolysis for ATP production, especially under hypoxic environment. Metabolic reprogramming in cancer drives an increased glycolytic rate that supports maximal production of nutrients for tumorigenesis. Our group has recently identified the post-translational modification enzyme, protein arginine methyltransferase 6 (PRMT6) to be frequently down-regulated and to exhibit a tumour suppressive effect in maintenance of cancer stemness in hepatocellular carcinoma (HCC) (Chan LH et al. Cell Reports 2018). Our current study finds transcriptome and metabolome profiling of HCC cells with PRMT6 repressed to exhibit enrichment of genes and metabolites involved in glycolysis. In vitro, PRMT6 negatively regulates glycolysis, glucose uptake, lactate production and pyruvate kinase activity in HCC cell lines and patient-derived organoids. Our previous work found PRMT6 to interfere with RAS/RAF binding by directly binding to CRAF and methylating arginine100 residue. Supporting the importance of PRMT6-mediated CRAF methylation, we find overexpression of catalytic inactive PRMT6 to exhibit no effect on glycolysis. MEK/ERK, known downstream effectors of RAS/RAF signalling, has been shown to induce nuclear PKM2 localization. Consistently, we find modulation of PRMT6 to negatively regulate ERK and PKM2 expression and localization. Rescue experiments involving the ERK inhibitor U0126 and shPKM2 further substantiate the importance of ERK/PKM2-mediated glucose metabolic reprogramming in HCC cells with PRMT6 suppressed. Functionally, inhibition of glycolysis by 2-deoxyglucose sensitized PRMT6 knockdown cells to sorafenib treatment in vitro and attenuated tumor growth in vivo. In addition, we also find PRMT6 expression to be regulated via hypoxia by binding of RE1-silencing transcription factor to the promoter region. Rescue experiments by re-expressing PRMT6 under hypoxic conditions further support the involvement of PRMT6 in driving glycolysis in oxygen deprived environments. Our work uncovers a critical function for PRMT6 in driving Warburg effect through regulating expression and localization of PKM2 via post-translational modification of CRAF, thereby promoting HCC initiation and sorafenib resistance.

Citation Format: Tin-Lok Wong, Lok-Hei Chan, Stephanie Ma. Down-regulation of PRMT6 drives Warburg effect through ERK induced relocalization of PKM2 to promote tumorigenicity and sorafenib resistance in hepatocellular carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1852.
Abstract 1857: Proscillaridin A induces apoptosis and suppresses non-small cell lung cancer tumor growth via calcium-induced DR4 up-regulation
Authors: Li Run-Ze , Fan Xing Xing , Yao Xiao- Jun , Leung Elaine L. , Liu Liang
Published: August 2019

Non-small cell lung cancer (NSCLC) is the predominant histological type of lung cancer and is characterized by the highest mortality and incidence rates among these types of malignancies. Cardiac glycosides, a class of natural products, have been identified as a potential type of chemotherapeutic agent. This study aims to investigate the anti-cancer effects and the mechanisms of action of Proscillaridin A (P.A) in NSCLC cells. In vitro sodium-potassium pump (Na+/K+ ATPase) enzyme assays indicated that P.A is a direct Na+/K+ ATPase inhibitor. P.A showed potent cytotoxic effects in NSCLC cells at nanomolar levels. Treatment mechanism studies indicated that P.A elevated Ca2+ levels, activated the AMPK pathway and down-regulated phosphorylation of ACC and mTOR. Subsequently, P.A increased death receptor 4 (DR4) expression and down-regulated NF-κB. Interestingly, P.A selectively suppressed EGFR activation in EGFR mutant cells but not in EGFR wild-type cells. In vivo, P.A significantly suppressed tumor growth in nude mice compared to vehicle-treated mice. Compared with the Afatinib treatment group, P.A displayed less pharmaceutical toxicity, as the body weight of mice treated with P.A did not decrease as much as those treated with Afatinib. Consistent changes in protein levels were obtained from Western blotting analysis of tumors and cell lines. Immunohistochemistry analysis of the tumors from P.A-treated mice showed a significant suppression of EGFR phosphorylation (Tyr 1173) and reduction of the cell proliferation marker Ki67. Taken together, our results suggest that P.A is a promising anti-cancer therapeutic candidate for NSCLC. Acknowledgements This work was supported by the Macau Science Technology Development Fund (project code: 021/2013/A1, 005/2014/AMJ & 010/2016/A1).

Note: This abstract was not presented at the meeting.

Citation Format: Run-Ze Li, Xing Xing Fan, Xiao- Jun Yao, Elaine L. Leung, Liang Liu. Proscillaridin A induces apoptosis and suppresses non-small cell lung cancer tumor growth via calcium-induced DR4 up-regulation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1857.
Abstract 1864: Verticillin A causes DNA damage and apoptosis in high grade serous ovarian cancer
Authors: Salvi Amrita , Austin Julia , Lantvit Daniel , Burdette Joanna
Published: August 2019

High grade serous ovarian cancer (HGSOC) is the most lethal gynecological malignancy affecting women worldwide and the fifth most common cause of cancer related deaths among U.S. women. New targeted therapies are needed to prevent HGSOC progression and metastasis related lethality from the disease. The goal of this study was to test the novel natural compound, Verticillin A, for its anticancer properties and mode of action in HGSOC cells. Verticillin A is an epipolythiodioxopiperazine (ETP) alkaloid that is isolated from several terrestrial and marine filamentous fungi and has been shown to be cytotoxic in several cancer cell lines including OVCAR8, OVCAR4 and Kuramochi. Our data indicated that Verticillin A treatment caused cytotoxicity in HGSOC cell lines in a dose-dependent manner.

Furthermore, treatment with Verticillin A in HGSOC cell line OVCAR8 and OVCAR4 enhanced apoptosis, which was demonstrated by PARP cleavage and Annexin V/ Propidium iodide staining. To determine whether Verticillin A caused in vivo tumor growth inhibition, OVCAR8-RFP cells were xenografted in mice to form tumors and the mice were treated with Verticillin A. Encapsulated nanoparticles of Verticillin A decreased tumor growth in vivo and had low cytotoxicity compared to the naked drug. RNA-Seq analysis was performed with OVCAR8 cells treated with Verticillin A and the data found an upregulation of apoptosis signaling pathway and oxidative stress response and downregulation of cancer stemness signaling pathways. A proteomic histone profiling performed in OVCAR8 cells indicated that Verticillin A caused epigenetic modifications with global changes in histone methylation and acetylation marks. Thus, our study identifies Verticillin A as a novel epigenetic modifier in ovarian cancer cells and indicates therapeutic potential for treatment of HGSOC.

Note: This abstract was not presented at the meeting.

Citation Format: Amrita Salvi, Julia Austin, Daniel Lantvit, Joanna Burdette. Verticillin A causes DNA damage and apoptosis in high grade serous ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1864.
Abstract 1868: B-125, a novel berberine derivative, acts as a better retinoid X receptor a agonist with stronger anti-tumor activity in colon cancer
Authors: Xu Beibei , Hu Tian hui , Xiong jing
Published: August 2019

Our previous study showed that Berberine binds to RXRα to suppress colon cancer growth (Ruan et. al., Oncogene 2017, 36: 6906). To achieve better RXRα binding activity, stronger anti-tumor effect and higher bioavailability, 21 novel berberine derivatives were designed based on the binding information of berberine to RXRα. Among them B-125 performs the best solubility, RXRE luciferase activity and tumor suppressing ability. NMR and fluorescent titration results show that B-125 retain the similar binding ability to RXRα compared with Berberine. CD study suggests that B-125 has stronger allosteric effect on RXRα than berberine. The bioavailability of B-125 is 25 times higher than berberine. In KM12C colon cancer cells, B-125 performs stronger RXRα dependent inhibitory effects than berberine. In vivo results showed that B-125 inhibits the growth of colon cancer xenograft in nude mice, and the effect is stronger than that of berberine. All the above results indicate that B-125 is a better anti-cancer drug than berberine with better RXRα modulation ability, higher bioavailability and stronger tumor suppressing effect. The study promotes B-125 as a potential novel RXRα based anti-cancer drug in the treatment of colon cancer.

Note: This abstract was not presented at the meeting.

Citation Format: Beibei Xu, Tian hui Hu, jing Xiong. B-125, a novel berberine derivative, acts as a better retinoid X receptor a agonist with stronger anti-tumor activity in colon cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1868.
Abstract 1869: Mechanistic evaluation of ergosterol peroxide onin vitrobreast cancer models
Authors: Santiago Camille L. , Rivas Fatima , Ling Taotao , Suarez-Arroyo Ivette J. , Ortiz Gabriela , Lacourt Mercedes Y. , Valentin Anibal , Lang Walter H. , Martínez-Montemayor Michelle M.
Published: August 2019

Ganoderma lucidum extract (GLE), an extensively studied mushroom for its anti-cancer and anti-inflammatory properties, has been shown to possess physiologically active compounds such as polysaccharides, triterpenoids and sterols. In our previous studies, we reported that commercially available GLE whole mushroom extract selectively inhibits cancer cell viability, induces apoptosis, reduces invasion, and regulates key signaling molecules in various cell models of breast cancer. Hence, we sought to elucidate the compounds responsible for the observed anti-cancer activity. Among the isolated compounds from GLE, we identified a steroidal compound, Ergosterol Peroxide (EP), which has shown antiproliferative activity against cancer. EP is a member of natural endoperoxides, featuring the peroxy- warhead that can lead to hydroxyperoxy radicals or be activated and react as nucleophile, leading to significant biological cytotoxicity against various cancer models (e.g. ovarian, liver, colon). We hypothesized that EP would promote cell death mechanisms in the aggressive breast cancer phenotype. Thus, in this study, we evaluated EP’s anti-cancer potential using immunoblotting, colony formation, cell motility, cell cycle and reactive oxygen species (ROS) production assays against human breast cancer SUM-149, MCF-7, MDA-MB-231 cellular models. We show that EP displays anti-proliferative effects through cell arrest in G1 phase, and apoptosis induction via caspase 3/7 activation. EP induced ROS and decreased the migratory and invasive phenotype of these cancer cells. Moreover, it inhibited the expression of total AKT1, AKT2, BCL-2, BCL-XL, Cyclin D1 and c-Myc. Our combined results indicate that EP from GLE is a promising molecular scaffold for further exploration as an anti-cancer agent,particularly in aggressive breast cancer models.

Citation Format: Camille L. Santiago, Fatima Rivas, Taotao Ling, Ivette J. Suarez-Arroyo, Gabriela Ortiz, Mercedes Y. Lacourt, Anibal Valentin, Walter H. Lang, Michelle M. Martínez-Montemayor. Mechanistic evaluation of ergosterol peroxide onin vitrobreast cancer models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1869.