bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 1787: Identification of factors governing sensitivity of NSCLC cell lines to inhibition of Poly (ADP-Ribose) Polymerase (PARP).
Authors: Kommajosyula Naveen , Cao Ye , Moreau Lisa , D'Andrea Alan , Shapiro Geoffrey I.
Published: August 2014

PARP inhibitors are emerging as important new anticancer agents, especially in cancers defective in homologous recombination (HR) repair, such as those lacking BRCA1 or BRCA2. To date, the potential role of PARP inhibition in NSCLC has not been extensively studied. As previously reported, we examined a panel of 26 genotypically-defined NSCLC cell lines for sensitivity to the PARP-1 inhibitor AG014699 (rucaparib) using colony formation assays. We identified 5 cell lines that are exquisitely sensitive (IC50 ≈ 50nM), 9 cell lines that are moderately sensitive (IC50 ≈ 60-500nM) and 12 cell lines that are resistant (IC50 > 5 μM). These data were confirmed with a second PARP inhibitor, AZD2281 (Olaparib). To determine whether sensitive cell lines have defective HR compared to resistant cell lines, we examined the formation of RAD51 foci. Both sensitive and resistant cell lines demonstrated efficient formation of RAD51 foci as well as gamma-H2AX foci in response to DNA damaging treatments, indicating correct initiation of HR. In resistant cell lines, the repair process following PARP inhibition is completed within 24 hours, with resolution of RAD51 and gamma-H2AX foci. However, in sensitive cell lines, these foci persist greater than 30 hours following DNA damaging treatments. These results suggest that although sensitive lines are able to initiate HR repair, they are unable to complete the process, so that RAD51 foci are not resolved. The persistence of DNA damage in these cell lines is confirmed by persistent gamma-H2AX focus formation as well as S/G2 arrest, the latter representing intact checkpoint control. Our results suggest that proteins required downstream of RAD51, including helicases and Holliday junction resolvases, are lacking in the sensitive lines. Consistent with this hypothesis, NCI-H520 cells, a highly PARP inhibitor-sensitive cell line, lacks expression of WRN, RECQL4 and RECQL5. siRNA-mediated depletion of these proteins individually sensitizes the resistant A549 cell line to PARP inhibition, with reduction in rucaparib IC50 by 100 fold. Our results may define a novel subset of NSCLCs with a late-step defect in HR that can be approached with PARP inhibition as a novel treatment strategy.

Citation Format: Naveen Kommajosyula, Ye Cao, Lisa Moreau, Alan D'Andrea, Geoffrey I. Shapiro. Identification of factors governing sensitivity of NSCLC cell lines to inhibition of Poly (ADP-Ribose) Polymerase (PARP). [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1787. doi:10.1158/1538-7445.AM2013-1787
Abstract 1792: MDM2 promoter variants and mRNA expression in irradiated lymphocytes.
Authors: Gansmo Liv B. , Knappskog Stian , Lonning Per E.
Published: August 2014

Background. The ubiquitin ligase protein MDM2 plays an important role in cellular processes like growth arrest, senescence and apoptosis, and one of its main targets is the key cell cycle regulator p53. MDM2 is found overexpressed in several solid tumors, and its dysregulation is caused by gene amplification or by enhanced transcription or translation. The MDM2 gene has two main promoters; promoter P1 is constitutive while P2 is considered to be inducible in response to cellular stress. One polymorphism located in the MDM2 promoter P2 region, SNP309T>G (rs2279744), has been shown to enhance Sp1 transcription factor binding and is associated with increased cancer risk. Recently we reported a second polymorphism SNP285G>C (rs117039649) located 24 bp upstream of rs2279744. SNP285C resides on the SNP309G allele and was found to reduce Sp1 binding and lower the risk of ovarian, endometrial and breast cancer. A third SNP located in the same region, SNP344T>A (rs1196333) has been found not to be associated with cancer risk. In this study we examined the expression levels from the two MDM2 promoters among individuals harboring the different SNP variants (SNP309T/G, SNP285G/C and SNP344T/A) before and after irradiation.

Materials and methods. Blood samples were collected from 219 healthy individuals. From this blood the buffy coat fraction was separated, divided into two and cultured. Prior to RNA extraction and subsequent cDNA synthesis, one half of the cells were irradiated with a dose equivalent to 3 Grey.

Each sample was investigated for SNP285, SNP309 and SNP44 status by sequencing, and MDM2 expression was determined by qPCR using hydrolysis probes. All statistical analyses were calculated using SPSS and GraphPad Prism 5.

Results. After stress (ionizing radiation) we observed, on average, a 8 and 60 fold increase in mRNA levels from promoter P1 and P2, respectively (p<0,0001). Statistical analysis of MDM2 mRNA expression from promoter P1 and P2, showed no significant difference between individuals harboring the different genotypes of SNP309 (TT/TG/GG), SNP285 (GG/GC/CC) or SNP344 (TT/TA/AA) before or after stress. Since the SNP285C allele counteracts the effect of SNP309G (reduces Sp1 binding), we analyzed the impact of SNP309G in the subgroup of individuals harboring SNP285 GG, but found no correlation to higher expression levels in this subgroup either.

Conclusions. Despite their association with risk of several major solid tumor forms, we found no correlation between MDM2 promoter SNP285 or SNP309 with mRNA expression levels in WBC.

Citation Format: Liv B. Gansmo, Stian Knappskog, Per E. Lonning. MDM2 promoter variants and mRNA expression in irradiated lymphocytes. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1792. doi:10.1158/1538-7445.AM2013-1792
Abstract 1794: Cross-regulation of polycomb group protein BMI1 and WNT inhibitors.
Authors: Cho Joon-Ho , Dimri Manjari , Dimri Goberdhan P.
Published: August 2014

Polycomb group (PcG) proteins are evolutionarily conserved gene silencers, which determine cell fate decisions during development. These proteins are often aberrantly expressed in cancer cells. In particular, BMI1 and EZH2 are known to be overexpressed in a number of human malignancies including breast and prostate cancers. In vitro models of cancer development strongly support oncogenic role of overexpressed BMI1 in cancer and metastasis. BMI1 is known to be required for self-renewal of neural, hematopoietic, intestinal and mammary stem cells. In addition, BMI1 is downregulated in senescent cells, and this downregulation may contribute to age-related pathologies. BMI1 is also suspected to play a role in cancer stem cell development and increase stem cell-ness of tumors to promote drug resistance. Despite its role in cancer, stem cell phenotype, development and aging, very little is known about the signaling pathways that regulate the expression of BMI1. Here we report that BMI1 activates WNT pathway and upregulates its target genes such as Cyclin D1 and c-Myc. Using promoter-reporter assays, quantitative RT-PCR and Western blot analyses, we show that BMI1 auto-activates its expression via an E-box present in its promoter. Because auto-activation of BMI1 depends on E-box sequences present in its promoter, we hypothesized that BMI1 may regulate expression of c-Myc directly or indirectly via activation of WNT pathway. Indeed, our data suggest that BMI1 upregulated expression of c-Myc via activation of WNT pathway. Further dissection of this regulation revealed that BMI1 represses expression of WNT inhibitors, in particular DKK family of proteins such as DKK1, DKK2 and DKK3. Interestingly, we also found that DKK1 inhibits expression of BMI1, which also depends on E-box present in BMI1 promoter. Thus BMI1 and WNT inhibitors such as DKK1 cross-regulate each other's expression. We speculate that such regulation might favor BMI1 overexpression in cancer cells via increased WNT activity and c-Myc expression. On the other hand, increased expression of WNT inhibitors such as DKK1 might favor BMI1 downregulation in senescent and aged tissues. Thus, a fine tuned positive feedback loop controls BMI1 expression via WNT signaling pathway, and this feedback loop may be relevant to the role of BMI1 in cancer, stem cells and senescence.

Citation Format: Joon-Ho Cho, Manjari Dimri, Goberdhan P. Dimri. Cross-regulation of polycomb group protein BMI1 and WNT inhibitors. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1794. doi:10.1158/1538-7445.AM2013-1794
Abstract 1795: Impact of ischemia time on mRNA and microRNA expression in surgical liver tissue.
Authors: Schuster Claudia , Thasler Wolfgang E. , Kirchner Thomas , Hlubek Falk
Published: August 2014

Human frozen tissues are one of the best sources for molecular analyses such as microarrays, qPCR or Next-Generation-Sequencing. In addition, frozen tissues are particularly valuable for biomarker identification. Several biobanks comprising non-fixed frozen tissues have been established alongside with corresponding clinical data repositories to facilitate biomarker studies relevant for clinical diagnostics. Apart from proteomic approaches, mRNA- and microRNA-expression profiles have shown to be highly valuable for biomarker studies. Since RNA is generally a fragile molecule, RNA integrity in tissue specimens has tremendous impact on gene expression analyses, requiring a rigorous quality assessment of biobank tissue samples. To address this issue, we established a tissue quality test system based on RNA integrity and differential gene expression. We used normal liver tissue, that was snap frozen after various periods of ischemia time. The RNA was isolated and the quality was assessed in four steps: First, the RNA was quantitated by spectrophotometry (NanoDrop) and total RNA quality was determined by on-chip electrophoresis (Experion). Second, the degree of RNA degradation and the maximum length of RNA molecules available for downstream applications was determined by amplicon length analysis using PCR amplification. Third, the RNA expression levels of selected genes were determined and correlated to the time and condition of ischemia. The genes analysed comprised highly regulated genes, signaling pathway genes and genes induced by hypoxia or apoptosis. Fourth, the expression of selected miRNAs involved in signaling pathway regulation was determined by quantitative PCR.

Taken together we analysed mRNA and miRNA stability in correlation to the time of warm and cold ischemia and its impact on signaling pathway regulation in liver tissue samples. The results enabled us to establish a RNA-based quality assessment procedure of tissue specimen for frozen tissue biobanks. This study may facilitate and optimise the logistics of biobanking processes.

Citation Format: Claudia Schuster, Wolfgang E. Thasler, Thomas Kirchner, Falk Hlubek. Impact of ischemia time on mRNA and microRNA expression in surgical liver tissue. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1795. doi:10.1158/1538-7445.AM2013-1795
Abstract 1808: Gene expression signature of malignant astrocytomas and its association with MGMT promoter methylation status.
Authors: Iuchi Toshihiko , Ohira Miki , Yokoi Sana , Kageyama Hajime , Hasegawa Yuzo , Kawasaki Koichiro , Sakaida Tsukasa , Nakagawara Akira
Published: August 2014

Background: MGMT promoter methylation has been reported as a predictive marker, not only for response to temozolomide (TMZ), but also for the longer survival of the patients with malignant astrocytomas (MAs) regardless of treatment with TMZ. This led us to hypothesize that methylation status of MGMT in MAs could somehow associate with epigenetic modification of other cancer-related gene promoters resulting in alterations of gene expression profiles and acquisition of therapy- sensitive characters. In this study, to elucidate the molecular characteristics that contribute to chemosensitivity and prognosis in MAs, we conducted gene expression profiling of the tumors with or without MGMT promoter methylation.

Materials and Methods: Forty-seven MAs including 5 anaplastic astrocytomas and 42 glioblastomas were enrolled in this study. Methylation status of MGMT gene promoter was evaluated by methylation-specific PCR and subsequent pyrosequencing. Gene expression profile was analyzed using 13,000 genes-cDNA microarray which was developed in our institute. Differentially expressed genes between MGMT-methylated and -unmethylated cases were picked up by statistical analysis (Wilcoxon test).

Results: MGMT promoter methylation was found in 26 out of 47 cases. Among the 13,000 genes examined, 163 genes demonstrated statistically significant difference in expression between MGMT-methylated and -unmethylated cases. 22 genes demonstrated lower expression in MGMT-methylated cases, while the remaining 141 genes showed higher expression in methylated cases. When we classify the cases into two groups according to the expression profiles of these 163 genes, survival of the patients were clearly divided (median survival: 18.9m vs. 9.7m, p=0.039). Annotation analysis indicated that the 22 genes with lower expression in MGMT-methylated tumors include those which actively participate in tumor progression, invasion and metastasis, and one of these showed a significant prognostic power in 47 MAs examined (p=0.049). Validation of methylation status of these gene promoters is underway.

Conclusion: We identified a gene expression signature strongly correlated with MGMT methylation in MAs, which might contribute to predict chemosensitivity of tumors as well as prognosis of the patients with MA in combination of MGMT methylation.

Citation Format: Toshihiko Iuchi, Miki Ohira, Sana Yokoi, Hajime Kageyama, Yuzo Hasegawa, Koichiro Kawasaki, Tsukasa Sakaida, Akira Nakagawara. Gene expression signature of malignant astrocytomas and its association with MGMT promoter methylation status. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1808. doi:10.1158/1538-7445.AM2013-1808
Abstract 1817: Expression of the Kaiso-binding partner Znf131 negatively correlates with cell proliferation in murine intestinal and human breast tumor tissues.
Authors: Longo Joseph , Robinson Shaiya , Chaudhary Roopali , Daniel Juliet M.
Published: August 2014

Znf131 is a relatively uncharacterized member of the POZ-ZF family of transcription factors with suspected roles in both vertebrate development and carcinogenesis. Previous studies from our lab identified Znf131 as a specific binding partner of another POZ-ZF protein, Kaiso, which has been implicated as a regulator of the canonical Wnt signaling pathway. Our lab successfully generated an intestinal-specific Kaiso overexpressing (KaisoTg/+) mouse model, which was found to exhibit enlarged crypts and mild hyperplasia in the small intestine. Several lines of evidence implicate Znf131 in cell proliferation, but whether Znf131 expression increases or decreases cell proliferation has yet to be elucidated. To determine whether Znf131 expression correlates with increased proliferation in hyperplastic KaisoTg/+ crypts, the expression and localization of Znf131 was correlated with the proliferation marker Ki-67 in KaisoTg/+ and wildtype (WT) mouse intestinal tissues. Znf131 nuclear expression was localized to the Paneth cell region of the crypts in both the KaisoTg/+ and WT small intestinal tissues, but decreased Znf131 expression was observed in the KaisoTg/+ model. Intriguingly, Ki-67 was localized to the progenitor cell region of the crypts and was excluded from Znf131-positive nuclei. In contrast to our hypothesis, these results suggest that Znf131 negatively correlates with cell proliferation. Since Znf131 has also been implicated as a regulator of ERα, we repeated these experiments using human breast tumor tissues to determine whether the observed results were tissue specific. We detected decreased nuclear expression of Znf131 in breast tumor tissues compared to matched normal tissues, and we observed a negative correlation between the nuclear expression of Znf131 and the histologic grade and stage of the tumor. Collectively, our results from both murine intestinal and human breast tumor tissues suggest a negative correlation between Znf131 nuclear expression and cell proliferation and raise the possibility that Znf131 may act as a tumor suppressor.

Citation Format: Joseph Longo, Shaiya Robinson, Roopali Chaudhary, Juliet M. Daniel. Expression of the Kaiso-binding partner Znf131 negatively correlates with cell proliferation in murine intestinal and human breast tumor tissues. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1817. doi:10.1158/1538-7445.AM2013-1817
Abstract 1836: Long noncoding RNA HOTAIR enhances aggressive biological behavior and is associated with short disease-free interval in human non-small cell lung cancer.
Authors: Nakagawa Takayuki
Published: August 2014

Lung cancer is the most common cause of cancer death worldwide. Non- small cell lung cancer (NSCLC) occupies more than 80% of all lung cancer. Overall, less than 10% of patients diagnosed with NSCLC survive five years after the diagnosis. Multidisciplinary management of NSCLC which contains surgery, chemotherapy and radiotherapy does not satisfactorily improve the patients’ prognosis. The pathogenic mechanisms contributing to the resistance to various therapeutic approaches in this cancer still remain to be clarified. HOTAIR is one of the large intervening noncoding RNA and interacts with the polycomb repressive complex 2 (PRC2) in the regulation of gene activities. Recently, the enhanced expression of this molecule has been shown to be associated with metastasis and/or poor prognosis of several human carcinomas such as breast, liver, colon and pancreas. However, little is known about the roles of this gene in lung cancer. Thus, we examined the involvement of HOTAIR in the development of NSCLCs. The expression of HOTAIR was examined in 77 NSCLCs and their corresponding normal lung tissues, and 6 metastatic lesions to brain by quantitative real-time RT-PCR. The high expression of HOTAIR (tumor/normal ratio > 2) was detected in 17 patients (22.1%) and was frequently found in patients with advanced stage, lymph node metastasis or lymphovascular invasion. The NSCLC patients with high expression of HOTAIR also showed significantly short disease free interval compared with those with low expression. Furthermore the metastatic lesions to brain demonstrated significantly higher HOTAIR expression than primary tissues. Accordingly, HOTAIR transfected A549 cells showed induced migration in vitro, and injected HOTAIR expressing cells into the tail vein of immunodeficient mice formed more metastases to liver or bone compared to empty vector transfected cells. We also found that the enhanced HOTAIR expression in lung cancer cells demonstrated the reduced expression of LAMB2 and LAMC3 both of which are downstream targets of PRC2. Taken together, these results might indicate that the evaluation of HOTAIR expression predict the poor outcome of NSCLC patients and that the overexpression of HOTAIR enhanced the aggressive biological behavior of NSCLC cells, at least in part, through the regulation of PRC2.

Citation Format: Takayuki Nakagawa. Long noncoding RNA HOTAIR enhances aggressive biological behavior and is associated with short disease-free interval in human non-small cell lung cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1836. doi:10.1158/1538-7445.AM2013-1836
Abstract 1840: Clinical significance of lincRNA-p21 in colorectal cancer.
Authors: Zhai Haiyan , Fesler Andrew , Schee Kristina , Fodstad Øystein , Flatmark Kjersti , Ju Jingfang
Published: August 2014

Large Intergenic Noncoding RNAs (LincRNAs) have been recently shown to be novel regulators for both transcription and posttranscriptional/translation. One of them, lincRNA-p21, was regulated by p53 and contributed to apoptosis in mouse embryonic fibroblasts. However, the impact of such regulation on colorectal cancer (CRC) is remained to be determined. In this study, we discovered that the expression level of lincRNA-p21 was increased by elevated wild type p53 induced by Nutlin in HCT116 colon cancer cells. The clinical significance of lincRNA-p21 was further investigated in 2 CRC patient cohorts. The expression of lincRNA-p21 was quantified by the real time qRT-PCR analysis using total RNAs extracted from snap fresh frozen CRC samples. Our results reveal that the expression level of lincRNA-p21 is significantly (P = 0.0208) lower in CRC tumor tissue when compared to the paired normal tissue from the same patient. There is no significant correlation of lincRNA-p21 with p53 status (wild type vs. mutant). Tumors in rectum show higher level of lincRNA-p21 than the ones in colon (P = 0.00005). In addition, lincRNA-p21 in stage III patients was significantly higher than stage I patients (P = 0.007). Elevated level of lincRNA-p21 was significantly associated with higher pT (P = 0.037 between pT 2 and 3), and vascular invasion (P = 0.017). LincRNA-p21 was not significantly associated with patient's overall survival. These results indicate that lincRNA-p21 may contribute to CRC disease progression.

Citation Format: Haiyan Zhai, Andrew Fesler, Kristina Schee, Øystein Fodstad, Kjersti Flatmark, Jingfang Ju. Clinical significance of lincRNA-p21 in colorectal cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1840. doi:10.1158/1538-7445.AM2013-1840
Abstract 1844: Reduced expression of miR-342-3p in prostate cancer.
Authors: Jones Dominique , Anene Divine , Aloway April , Anene Praise , Avila Diana , Gobejishvili Leila , Barve Shirish , McNally Lacey , Kidd LaCreis
Published: August 2014

Patients with bone metastasis of the prostate have a 5-year survival rate of less than 30%. Due to inconsistencies in the presentation, prognosis, and treatment options of metastatic prostate cancer (PCa), biomarkers are urgently needed for personalized treatment of this disease. MicroRNAs (miRNAs) are small, non-coding, single-stranded endogenous RNAs that regulate the expression of multiple messenger RNA targets. Studies have demonstrated that these non-coding RNAs are significantly expressed in lung, breast and prostate cancer tumors. We hypothesize that miRNAs are differentially expressed between non-cancerous and aggressive tumor phenotypes in PCa, e.g. bone-specific metastasis. To test this hypothesis, we evaluated 384 miRNAs in the serum of stage-matched patients with stage I (n = 5), stage III (n = 5), stage IV (n = 5) PCa compared to non-cancerous age and stage-matched controls (n = 5). Total RNA was isolated from 500 μl of serum (Bioserve Biotechnologies, Ltd). The expression profiles of miRNAs were measured using TLDA cards and statistical analyses were performed using Expression Suite Software version 1.0. MiRNAs (miR-106b/17, -302b, -342-3p) were differentially expressed in the serum of PCa patients with (stage I, III, IV) when compared to controls. Mir-342-3p was significantly reduced in expression (P = 0.018-0.028) in all PCa patients relative to non-cancerous controls, after adjusting multiple hypothesis testing. However, other serum miRNAs were differentially expressed for only stage III PCa (P=0.001-0.018). Validation of these differentially expressed miRNAs in large sample sizes will lead to the identification of pre- and metastatic biomarkers. Ultimately, the investigation of these biomarkers will improve personalized treatment of PCa patients.

Citation Format: Dominique Jones, Divine Anene, April Aloway, Praise Anene, Diana Avila, Leila Gobejishvili, Shirish Barve, Lacey McNally, LaCreis Kidd. Reduced expression of miR-342-3p in prostate cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1844. doi:10.1158/1538-7445.AM2013-1844
Abstract 1846: Potential of tumor-suppressive miR-596 targeting LGALS3BP as a therapeutic agent in oral cancer.
Authors: Kozaki Ken-ichi , Endo Hironori , Muramatsu Tomoki , Furuta Mayuko , Uzawa Narikazu , Pimkhaokham Atiphan , Amagasa Teruo , Inazawa Johji
Published: August 2014

The incidence and mortality statistics for oral squamous cell carcinoma (OSCC) were 10th and 12th, respectively, in human cancers diagnosed worldwide in 2008. In this study, to identify novel tumor-suppressive microRNAs (TS-miRNAs) and their direct targets in OSCC, we performed methylation-based screening for 43 miRNAs encoded by 46 miRNA genes located within 500bp downstream of 40 CpG islands and genome-wide gene expression profiling in combination with a prediction database analysis, respectively, in 18 cell lines, resulting in the identification of a novel TS-miRNA miR-596 directly targeting LGALS3BP/Mac-2 BP/90K. DNA hypermethylation of CpG island located 5’-upstream of miR-596 gene was frequently observed in OSCC cell lines (100% of 18 cell lines) and primary OSCC cases (46.2% and 76.3% of 26 Japanese and 38 Thais primary cases) in a tumor-specific manner. The ectopic transfection of double-stranded RNA (dsRNA) mimicking miR-596 or specific siRNA for LGALS3BP significantly induced growth inhibition and apoptosis in cell lines lacking miR-596 expression or overexpressing LGALS3BP, respectively, in a manner associated with a suppression of ERK1/2 phosphorylation. Moreover, we also mention the effect of dsRNA mimicking miR-596 on the growth of an OSCC cell line in vivo. Our findings define a central role for miR-596 in OSCC and suggest the potential of miR-596 as an anti-cancer agent for miRNA replacement therapy in OSCC.

Citation Format: Ken-ichi Kozaki, Hironori Endo, Tomoki Muramatsu, Mayuko Furuta, Narikazu Uzawa, Atiphan Pimkhaokham, Teruo Amagasa, Johji Inazawa. Potential of tumor-suppressive miR-596 targeting LGALS3BP as a therapeutic agent in oral cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1846. doi:10.1158/1538-7445.AM2013-1846
Abstract 1847: Molecular profiles of microRNA in endometrial carcinoma using paraffin-embedded (FFPE) specimens.
Authors: Lee Taek Sang , Jeon Hye-Won , Kim Yong-Beom
Published: August 2014

MicroRNAs (miRNAs) are small non-coding RNAs that regulate

mRNA stability and protein expression at post-transcriptional level.

Certain miRNAs have been demonstrated to act either as oncogenes or tumor suppressors. The specific expression profiles of miRNAs have been found in many human cancers, but the role of miRNAs in endometrioid endometrial cancer (EEC) remains poorly understood. Most miRNA profiling studies have used fresh tissue samples. This study was to provide the candidate miRNAs for further confirming the role of miRNAs in carcinogenesis of EEC and to explore whether FFPE material would be suitable for miRNA profiling. We found the differences in miRNA expression profile using human miRNA microarray in EECs and normal endometrium. Of those, the miR-200a*, miR-200b*, miR-141, miR-182, and miR-205 were greatly enriched. The expressions of these 5 miRNAs were validated using quantitative real time reverse transcription-PCR (qRT-PCR). Then, we performed qRT-PCR profiling of miR expression in 30 microdissected formalin-fixed paraffin-embedded (FFPE) specimens (20 EECs, 10 non-tumor specimens) and reconfirmed the results of differential expression between cancer and normal tissue. We next tested whether specific inhibition of overexpressed microRNAs would alter the chemosensitivity. In in vitro cell viability assay, anti-miR200b* slightly enhanced cisplatin cytotoxicity compared with negative control although it showed marginal statistical significance (p=0.07). This information provided the candidate miRNAs for further confirming the role of miRNAs in carcinogenesis of EEC and potentially serving as a diagnostic or therapeutic tool. FFPE specimens of endometrial tissues are suitable as a source for miRNA microarray profiling.

Citation Format: Taek Sang Lee, Hye-Won Jeon, Yong-Beom Kim. Molecular profiles of microRNA in endometrial carcinoma using paraffin-embedded (FFPE) specimens. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1847. doi:10.1158/1538-7445.AM2013-1847
Abstract 1848: Let-7 brings new insights into chronic myeloid leukemia therapy.
Authors: Yi Bin , Li Xiaobo , Du Wenjun , Piazza Gary A. , Xi Yaguang
Published: August 2014

Human chronic myelogenous leukemia (CML) is a malignancy of pluripotent hematopoietic cells that is caused by the deregulated activity of the tyrosine kinase that is encoded by the chimeric bcr-abl oncogene. Given that CML cells are usually highly resistant to chemotherapy, novel and more efficacious strategies against this disease are urgently needed. MicroRNA (miRNA) is a set of newly discovered 20-22 nucleotides RNA molecules, and they broadly repress their cognate target genes at post-transcriptional/translational level. Up to date, there are approximately 2,000 human miRNA transcripts have been characterized, which are estimated to modulate more than 30% human genes and are widely involved in many essential biological processes including differentiation, proliferation, apoptosis, and also tumorigenesis. In this study, we studied let-7, a miRNA with tumor suppressive signature, for its therapeutic potential in CML. When treating CML K562 and KU812 cell by imatinib, let-7 can be significantly induced. Overexpression of let-7 can sensitize K562 and KU812 cells to imatinib, while knock-down of let-7 can increase the drug resistance of these cells. The mechanistic studies found that let-7 was able to promote apoptosis of CML cells, inhibit the tumor cell proliferation, and lead to a cell cycle arrest in the G0/G1 phase. These results demonstrate that let-7 is a potential target for treating CML by imatinib and/or other anti-cancer druges. The pro-apoptosis and anti-proliferation roles of let-7 in CML cells may provide novel insights into discovery and development novel drugs for conquering this malignant disease.

Citation Format: Bin Yi, Xiaobo Li, Wenjun Du, Gary A. Piazza, Yaguang Xi. Let-7 brings new insights into chronic myeloid leukemia therapy. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1848. doi:10.1158/1538-7445.AM2013-1848

Note: This abstract was not presented at the AACR Annual Meeting 2013 because the presenter was unable to attend.
Abstract 185: Secoisolariciresinol diglucoside (SDG, flaxseed lignan) improves biomarkers of early mammary gland cancer progression in a rat model of breast and ovarian cancer.
Authors: Delman Devora , Kimler Bruce F. , Fabian Carol J. , Petroff Brian K.
Published: August 2014

Breast cancer prevention efforts increasingly are focused on potentially beneficial dietary modifications due to their ease of implementation, wide acceptance and excellent subject compliance. SDG is a bioactive component of flaxseed suggested to have beneficial SERM-like effects in females at high risk for the development of breast cancer. In parallel with a human phase II prevention trial, female Sprague Dawley rats (n=10-12/group) received 0, 1, 10 or 20 mg/kg/day SDG in the feed. Simultaneously, rats were induced to concurrent mammary and ovarian cancer progression in a previously validated model using sustained release 17β-estradiol and local ovarian DMBA treatment starting at 6 weeks of age. Serum was collected at 3 weeks to measure steady state SDG metabolite concentrations. Mammary gland and ovarian tissues were collected at 3 months post-treatment and examined for changes in epithelial cell proliferation (Ki-67, cell counts), histopathology and dysplasia scores as well as a panel of cancer risk and progression biomarker genes. Carcinogen treatment markedly elevated dysplasia scores while SDG decreased dysplasia in a dose-dependent fashion, with an approximately 50% improvement the highest dose. Mammary epithelial cell numbers were increased by carcinogen and this effect was mitigated similarly at all doses of SDG and reflected in reduced Ki-67 expression. Overall, SDG decreased mammary epithelial proliferation and dysplasia resulting from carcinogen treatment. This preclinical benefit occurred at serum concentrations similar to our human pilot study, in which dietary SDG reduced KI-67 expression in mammary epithelial cells, and decreased the proportion of women with RPFNA atypia.

Supported in part by funds from Komen for the Cure grant KG101039.

Citation Format: Devora Delman, Bruce F. Kimler, Carol J. Fabian, Brian K. Petroff. Secoisolariciresinol diglucoside (SDG, flaxseed lignan) improves biomarkers of early mammary gland cancer progression in a rat model of breast and ovarian cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 185. doi:10.1158/1538-7445.AM2013-185
Abstract 1854: Metabolic cross talk between omental derived adipose stromal cells from lean and obese patients with ovarian cancer cells.
Authors: Rizi Bahar Salimian , Nowicka Alexandra , Klopp Ann H. , Nagrath Deepak
Published: August 2014

Advanced-stage ovarian cancers have been shown to be metastatic in peritoneal cavity. Ovarian cancer metastasis is diagnosed primarily in omentum which is a soft fatty pad that extends from stomach and covers the bowel. The location of excess adipose tissue appears to be an important factor which influences the effect of obesity on cancer incidence. For example, increased total body obesity is associated with relative risk of 1.14 of developing ovarian cancer. However, a waist to hip circumference ratio of >0.85 is associated with a much higher 8-fold increased risk of developing ovarian cancer. Individuals with greater waist to hip ratio generally have more visceral adipose including omental adipose. The tumor promoting effects of regional adipose may be attributed, at least in part, to the presence of a population of mesenchymal stem cells (MSC) in adipose tissue. Adipose stem cells or adipose derived stromal cells (ASCs) are a multi-potent population of mesenchymal stem cells, which support cancer progression in many models. These cells are uniquely tumor tropic, migrating into tumor stroma from regional sources where they support formation of tumor stroma elements and promote tumor progression. Here, we use metabolic foot-printing approach to dissect the metabolic networks regulated by ASCs and ACs, as well as their role in imparting drug resistance to tumors by deregulating metabolic pathways in ovarian cancer cells. Importantly, we found that O-ASCs from obese patients differentially induce metabolic reprogramming in cancer cells and that cancer cells induce reciprocal metabolic alterations and phenotypic changes in O-ASCs from lean patients.

Citation Format: Bahar Salimian Rizi, Alexandra Nowicka, Ann H. Klopp, Deepak Nagrath. Metabolic cross talk between omental derived adipose stromal cells from lean and obese patients with ovarian cancer cells. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1854. doi:10.1158/1538-7445.AM2013-1854
Abstract 1860: Metabolomics for the identification of prognostic biomarkers of pancreatic cancer.
Authors: Unger Keith , Kaur Prabhjit , Cheema Amrita K.
Published: August 2014

Introduction: Although the survival outcomes of Pancreatic Ductal Adenocarcinoma (PDAC) continue to be poor, clinical and basic research in this field is disproportionately under-represented as compared to other cancer sites. Currently, there is no blood or fluid test for diagnosis or prognosis of PDAC. Sensitive and specific biomarkers are thus critical for improving clinical outcomes of PDAC. Our goal in this study was to identify molecular features that could be used for disease stratification. The underlying hypothesis was that targeted, quantitative evaluation of molecular fingerprints of PDAC in serum, calculated originally via matched tissue metabolomic profiles using an untargeted approach may have direct clinical applicability.

Approach: We have used mass spectrometry based metabolomics, an emerging field that provides new information on biological perturbations based on changes in multiple endogenous metabolites. These metabolites represent the endpoint of cellular processes and are hence a direct readout of the phenotype or the physiological status. Detection of PDAC using a metabolomics approach is based on the establishment of specific key metabolite signatures in pancreatic tumor tissue derived from patients diagnosed with PDAC. A shortlisted panel of these putative markers was tested for their pre-clinical performance using serum samples from the same patients. This combinatorial approach allowed us to interrogate the PDAC tissue metabolome in a global and unbiased fashion and subsequently test the clinical applicability using a targeted approach in serum samples.

Results: The untargeted metabolomics profiling resulted in the identification of a panel of key metabolites which could help discriminate PDAC tissue profiles from pancreatitis and colo-rectal tumor tissue. Validation of these metabolites in serum is ongoing.

Conclusion: Our results demonstrate the power of metabolomics for developing clinical assays for diagnosis and prognosis of PDAC. Identification of cellular target molecules, associated with pancreas cancer oncogenesis, progression and metastasis is critical for designing new treatment options for advanced stage disease. Developing a specific and sensitive panel of bio-markers offers a pragmatic approach towards increasing overall survival rates; identify molecular targets for therapeutic development, improving treatment strategies and thus clinical outcomes

Supported by American Cancer Society

Citation Format: Keith Unger, Prabhjit Kaur, Amrita K. Cheema. Metabolomics for the identification of prognostic biomarkers of pancreatic cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1860. doi:10.1158/1538-7445.AM2013-1860
Abstract 1864: Mitochondrial bioenergetics of metastatic breast cancer cells in response to decreasing oxygen tension.
Authors: Vayalil Praveen K. , Diers Anne R. , Olivia Claudia R. , Griguer Corinne E. , Darley-Usmar Victor , Hurst Douglas R. , Welch Danny R. , Landar Aimee
Published: August 2014

Solid tumors are characterized by regions of low oxygen tension, which play a central role in tumor progression and resistance to therapy. The major organelle affected by reduced oxygen tension is the mitochondrion, which has to functionally adapt to maintain cellular bioenergetics for the cell survival. In the present study, a novel experimental approach was developed to examine the real-time bioenergetic changes during adaptation to various oxygen tensions ranging from 20% to < 1% oxygen using highly sensitive extracellular flux technology. Oxygen was gradually removed from the culture medium, and bioenergetic changes were measured in normal breast epithelial (MCF10A) and metastatic cancer cell lines (MDA-MB-231 and MCF10CA clones). We found that breast cancer cells, but not MCF10A cells, rapidly responded to low oxygen tension by stabilizing HIF-1α, increasing hypoxia responsive gene expression, and stimulating cellular uptake of glucose, confirming previous observations. In addition, breast cancer cells increased extracellular acidification rate (ECAR) or glycolysis during adaptation to low oxygen tension, and this effect was markedly lower in MCF10A cells. Interestingly, breast cancer cells exhibited a biphasic response in oxygen consumption rate (OCR) as the oxygen tension was reduced gradually from 20% to <1.0%, a response not previously described. This effect is HIF-1α-dependent, as silencing HIF-1α function in cancer cells completely abolished the biphasic response in OCR and increase in ECAR. Moreover, cancer cells demonstrated the ability to restore and maintain its OCR steadily at specific oxygen tension either during deoxygenation or reoxygenation, an effect not observed in HIF-1α silenced cells. Additional studies confirmed that the initial stimulation of OCR is due to increased mitochondrial respiration. In conclusion, our results suggest that HIF-1α provides high degree of bioenergetic flexibility under different oxygen tensions which may confer an adaptive advantage in the ever-changing tumor microenvironment as well as during invasion and metastasis. Moreover, these differences may be useful in screening novel therapeutic agents that target the bioenergetics of cancer cells in response to low oxygen tension.

Citation Format: Praveen K. Vayalil, Anne R. Diers, Claudia R. Olivia, Corinne E. Griguer, Victor Darley-Usmar, Douglas R. Hurst, Danny R. Welch, Aimee Landar. Mitochondrial bioenergetics of metastatic breast cancer cells in response to decreasing oxygen tension. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1864. doi:10.1158/1538-7445.AM2013-1864
Abstract 1878: Acetyl coA carboxylase1 and its role in prostate cancer initiation and progression.
Authors: Davis Amanda L. , Scott Kristen , Chen Yong , Kridel Steven
Published: August 2014

The alteration of cellular metabolic processes is a common event in the initiation and progression of several cancer types. One metabolic hallmark of cancer cells is an increase in de novo lipogenesis. The enzymes responsible for de novo fatty acid synthesis are overexpressed in cancer, suggesting that these enzymes may be appropriate targets in efforts to inhibit or treat disease. Specifically, Acetyl CoA Carboxylase 1 (ACC1), the cytosolic enzyme that catalyzes the rate limiting step of de novo fatty acid synthesis through the ATP and biotin-dependent carboxylation of acetyl-CoA to malonyl-CoA, has received attention as a potential target for cancer treatment. Pharmacological inhibition and siRNA mediated knockdown of ACC1 has been shown to selectively kill prostate cancer cells in vitro by denying cells of adequate amounts of fatty acids needed to proliferate and survive. Although ACC1 has been implicated in cancer, its role has not been examined in a spontaneous model of cancer. To address this issue, we first generated mice with prostate-specific deletion of exon 22 of the Acetyl CoA Carboxylase 1 (ACCL/L) gene by breeding with Probasin-Cre mice. Loss of ACC1 activity did not appear to affect prostate function as survival, prostate weight, histology, and breeding was similar between ACCL/L Cre+ and ACCL/L Cre− mice. To determine the role of ACC1 in prostate cancer, the ACC+/L mice were crossed with PtenL/L; Cre+ mice. To our surprise, ACC1 activity was not required for prostate cancer development or progression in vivo, despite its apparent requirement in vitro. Total prostate weight and individual lobe weight did not differ among ACC+/L; PtenL/L; Cre+ mice, ACCL/L; PtenL/L; Cre+ mice and ACC1+/+; PtenL/L; Cre+ mice. These early studies suggest that ACC1 activity, and perhaps the fatty acid synthesis pathway, may not be required for prostate cancer development. The role of ACC1 in redox modulation, rescue of impaired de novo fatty acid synthesis by circulating and dietary fatty acid, and the potential compensation for ACC1 activity by ACC2 in prostate cancer are possible explanations for this unexpected phenotype. These results could have significant impact on the development and use of anti-cancer therapeutics that target the fatty acid synthesis pathway.

Citation Format: Amanda L. Davis, Kristen Scott, Yong Chen, Steven Kridel. Acetyl coA carboxylase1 and its role in prostate cancer initiation and progression. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1878. doi:10.1158/1538-7445.AM2013-1878