bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 1660: Cholesterol efflux transporter gene expression predicts clinical outcome in serous ovarian cancer
Authors: Henderson Michelle J. , Hedditch Ellen L. , Russell Amanda J. , deFazio Anna , Emmanuel Catherine , George Joshy , Chenevix-Trench Georgia , Bowtell David , Norris Murray D. , Haber Michelle ,   The Australian Ovarian Cancer Study Group
Published: June 2012

Ovarian cancer is a devastating disease. More than half the women diagnosed with advanced disease will die within five years. Tumours displaying serous histology are the most common, and although initially responsive to current chemotherapy regimens, the disease is characterised by a frequent rate of relapse, often with disease that is resistant to further treatment. Tumours displaying serous histology are the most common and often have the worst prognosis. The ATP-binding cassette (ABC) transporter superfamily consists of 48 functional transmembrane proteins which are further classified into seven subfamilies according to sequence similarity, designated A through G. Various members of the B, C and G branches are well-known for their abilities to convey drug resistance to cancer cells in vitro, but their precise roles in determining clinical outcome are still unclear. In addition, ABC transporters have important and diverse physiological roles through active transport of a variety of endogenous substrates, which could also contribute to tumour phenotype and treatment response. This is the first study to explore the entire ABC transporter gene family in relation to clinical outcome of ovarian cancer. Using a Taqman low density array format for real-time PCR, we examined expression of all ABC transporter genes in a cohort of 150 serous ovarian cancers. Kaplan-Meier survival analysis revealed that expression of multiple ABCA family transporters was significantly associated with progression-free or overall survival and multivariate modelling identified ABCA1, ABCA5, ABCA6, ABCA8 and ABCA9 as new prognostic markers for serous ovarian cancer that are independent of established clinical indicators. The prognostic significance of ABCA family transporter expression was validated in an independent microarray dataset consisting of 350 serous tumours available through The Cancer Genome Atlas. These ABCA family transporters are not known to transport drugs but instead function in cellular lipid trafficking and cholesterol homeostasis, suggesting that treatment failure may involve mechanisms other than simple efflux of chemotherapeutic drugs. In light of accumulating evidence for the importance of cholesterol and bioactive lipids in several cancers, this study highlights an important area for investigation into the biology and treatment of serous ovarian cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1660. doi:10.1158/1538-7445.AM2011-1660
Abstract 2153: P34SEI-1 inhibits ROS-induced cell death through suppression of ASK1
Authors: Jin Dong-Hoon , Hong Seung-Woo , Shin Jae-Sik , Yoon Dok Hyun , Na Young-Soon , Hong Yong Sang , Lee Jae-Lyun , Ryu Min-Hee , Kim Tae-Won , Lee Won-Keun
Published: June 2012

Apoptosis signal-regulating kinase (ASK) 1 is a key factor for controlling cellular events including cell cycle, senescence or apoptosis, in response to reactive oxygen species (ROS). However, the mechanisms that regulate ASK1 protein remain largely unexplored. In this study we demonstrate that p34SEI-1 which is both a positive cell cycle regulator as well as an oncogenic protein, inhibits ROS-induced cell death by suppressing ASK1. We first found that p34SEI-1-expressing cells have enhanced resistance to hydrogen peroxide (H2O2). We found that ASK1 phosphorylation induced by H2O2 was clearly inhibited in two, colon cancer cells, i.e. HCT116 and SW620, which ectopically express p34SEI-1. Moreover transfection with p34SEI-1 resulted in a decrease in the ASK1 protein level. Surprisingly, p34SEI-1 induced the ubiquitination of ASK1, however, there is no interaction between p34SEI-1 and ASK1. These results suggest that p34SEI-1 inhibits ROS-induced cell death through the induction of ASK1 ubiquitination.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2153. doi:10.1158/1538-7445.AM2011-2153
Abstract 2165: Identification of a novel pathway of castrate resistant prostate cancer (CRPCa) growth
Authors: Mehraein-Ghomi Farideh , Basu Hirak S. , Miyamoto Shigeki , Wilding George
Published: June 2012

Development of an effective therapy to prevent PCa occurrence, recurrence and/or progression remains an unmet medical need. This is mainly due to a poor understanding of the mechanism of PCa occurrence and progression.

There is accumulating evidence that ROS (Reactive Oxygen Species) such as hydrogen peroxide, superoxide, hydroxyl radical, etc. that are produced in high amounts in PCa cells may be a major factor in PCa occurrence and its progression to androgen-independence. One of the ROS (H2O2) plays a key role in triggering growth signals and expression of transcription factors to sustain growth of androgen-dependent PCa cells in the absence of androgen. One such factor is Nuclear Factor κB (NF-κB) that may sustain cell survival by preventing apoptosis and inducing cell proliferation. NF-κB activation kinetically correlates with androgen-induced ROS production in cultured LNCaP human PCa cells. This activation is also seen in resected PCa tissues from patients, who subsequently progressed to CRPCa.

Our published data show that androgen induces an up-regulation of spermidine/spermine acetyl transferase (SSAT) mRNA as well as enzyme activity that initiates polyamine oxidation in LNCaP cells after 72 h exposure. Because of the unusually high polyamine levels in the PCa cells, polyamine oxidation causes a large increase in ROS production that is abrogated by silencing SSAT expression in PCa cells stably transfected with shRNA against SSAT (siSSAT).

To determine whether SSAT is required for NF-κB activation following prolonged androgen stimulus, we transfected 3xκB-luciferase vector containing NF-κB consensus binding sites-luciferase reporter construct along with a β-gal expression vector (to control for the transfection efficiency) into both wild type LNCaP cells and its siSSAT clones. While 72 h androgen exposure causes an over 30-fold induction of luciferase activity in wild type LNCaP cells, no activation of NF-κB was observed in the siSSAT clones. These data clearly show a strong SSAT induction is required for a robust activation of NF-κB in androgen-treated PCa cells.

Multiple published reports show that NF-κB can also induce SSAT in several human cancer cells. Thus, our data suggest an intriguing mechanism of CRPCa progression, where androgen induced SSAT expression and consequent upregulation of NF-κB can set up an autocrine feed forward loop of SSAT-ROS-NFκB-SSAT that can sustain PCa cell proliferation in the absence of androgen that can lead to CRPCa growth.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2165. doi:10.1158/1538-7445.AM2011-2165
Abstract 2201: Involvement of somatic mutations in silencing cystatin E/M tumor suppressor gene in breast cancer
Authors: Venkatesan Natarajan , Issakhanian Shawnt P. , Ginther Charles G. , Slamon Dennis J. , Srivatsan Eri S. , Veena Mysore S.
Published: June 2012

Cystatin E/M is a cysteine protease inhibitor that has a tumor suppressive function in various cancers. Although promoter methylation is implicated in breast cancer, we wanted to determine whether the gene is also inactivated by somatic mutations. Thus, we analyzed breast cancer tissues and cell lines for the expression of Cystatin E/M and its effect on cancer cell growth and proliferation. RNA expression was observed in 3 (BT20, MB231 and ZR75.1) of 10 breast cancer cell lines by microarray and RT/PCR; however, the protein was not detectable in any of these cell lines by Western blotting indicating RNA and/or protein stability as a possible mechanism. Ectopic expression of cystatin E/M in MB435 cells, a cell line that did not show the RNA or protein expression, resulted in the inhibition of cell proliferation as studied by MTT assay. Western blotting and immunofluorescence studies indicated a reduced expression of its substrate cathepsin L with the reexpression of cystatin E/M. Varying expression of cystatin E/M (absent to strong) was also seen in a cohort of 24 human breast tumors; 8 of these tumors showed increased cathepsin L levels compared to a normal breast specimen. A mutation of Q47 to a stop codon in exon1 was observed in 2 tumor samples. These studies indicate that cystatin E/M may be inactivated by somatic mutations and the protein mediates tumor suppression by regulating its substrate cathepsin L in breast cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2201. doi:10.1158/1538-7445.AM2011-2201
Abstract 2207: Functional interrogation of the colorectal cancer genome identifies numerous suppressors of anchorage-independent growth
Authors: Eskiocak Ugur , Kim Sang B. , Ly Peter , Roig Andres I. , Biglione Sebastian , Komurov Kakajan , Cornelius Crystal , Wright Woodring E. , White Michael A. , Shay Jerry W.
Published: June 2012

INTRODUCTION: High throughput cancer genome sequencing efforts are leading to the identification of frequently mutated genes in cancer. Unfortunately, the extreme diversity of lesions being detected presents a challenge to segment causal from coincidental mutations and to elucidate how causal lesions disrupt regulatory networks to drive cancer processes. AIMS AND METHODS: Given that a common early perturbation in solid tumor initiation is bypass of matrix-dependent proliferation restraints, we used immortalized human colonic epithelial cells (HCECs) to identify suppressors of anchorage-independent growth by conducting a soft-agar based shRNA screen within frequently mutated colorectal cancer (CRC) genes. RESULTS AND CONCLUSIONS: Remarkably, depletion of 65 of the 151 frequently CRC-mutated genes tested collaborated with K-RASV12 or TP53 knockdown to promote anchorage-independent proliferation of HCECs. These candidates fall under a variety of different signaling pathways, but in particular JNK signaling was found to be a master suppressor of anchorage-independent growth in normal HCECs. We have identified additional members of an extensive gene network specifying matrix-dependent proliferation, by constructing an interaction map of these confirmed progression suppressors with the ∼700 rare CRC-mutated genes and experimentally verifying soft-agar growth enhancement in response to depletion of these genes. Collectively, this study reveals a profound diversity of fragile nodes within a fundamental tumor suppressor network, perturbation of which leads to enhanced cell-autonomous proliferative fitness. These studies establish the importance of functionally annotating cancer genomes using biologically relevant assays.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2207. doi:10.1158/1538-7445.AM2011-2207
Abstract 2209: Downregulation of LKB1 in high-grade endometrial carcinoma
Authors: Co Ngai Na Chloe , Iglesias David A. , Schmandt Rosemarie , Lu Karen H.
Published: June 2012

Objective: LKB1/STK11 encodes a serine/threonine kinase that regulates cell polarity, proliferation and energy metabolism via the AMPK signaling pathway. Germline mutations of LKB1 are responsible for Peutz-Jeghers syndrome, which is characterized by hamartomatous polyps and increased incidence of several cancers. It has been demonstrated that LKB1 null mice develop invasive endometrial cancer. Our lab has previously shown that 5 of 26 (19%) of human endometrial cancers exhibited loss of LKB1 protein by Western blot analysis. The purpose of this study was to examine the expression of LKB1 in a larger set of endometrial cancers and to determine if mutations in LKB1 occur in these tumors.

Methods: LKB1 protein levels were evaluated in 20 normal endometrial tissues, 17 Grade 1, 24 Grade 2, and 28 Grade 3 endometrioid endometrial adenocarcinomas by immunohistochemical staining. Laser-capture microdissection (LCM) was used to isolate RNA from 22 Grade 1, 21 Grade 2 and 23 Grade 3 fresh frozen endometrioid endometrial tissues; and LKB1 mRNA expression levels in microdissected tumor samples were quantified by TaqMan quantitative PCR. Direct genomic DNA sequencing of LKB1 coding exons were performed on 20 microdissected high-grade tumors.

Results: While no significant difference in LKB1 expression was observed between normal endometrium, Grade 1 and 2 endometrial tumors, LKB1 staining was significantly lower in Grade 3 tumors when compared with normal endometrium (P<0.0001), Grade 1 (P<0.0001) and Grade 2 (P=0.016) tumors. Downregulation of LKB1 mRNA level was also demonstrated in microdissected Grade 3 endometrial tumor samples. Direct genomic DNA sequencing of LKB1 coding exons revealed a single amino acid change (L201Q) in only 1 of 20 Grade 3 endometrial tumors, suggesting that DNA mutation is not the major mechanism leading to the loss of LKB1.

Conclusion: Our findings of decreased expression of LKB1 in high-grade endometrial cancers supports the hypothesis that loss of LKB1 may contribute to the development of high-grade endometrioid endometrial cancer. We are currently evaluating the mechanisms by which LKB1 levels are regulated in endometrial cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2209. doi:10.1158/1538-7445.AM2011-2209
Abstract 221: TP53 mutations in serous tubal intraepithelial carcinoma, the putative precursor lesion of ovarian high-grade serous carcinoma
Authors: Kuhn Elisabetta , Kurman Robert J. , Soslow Robert A. , Han Guangming , Wang Tian-Li , Shih Ie-Ming
Published: June 2012

Somatic mutation of TP53 is the most common molecular genetic alteration in high grade serous carcinoma (HGSC) of the ovary, occurring in more than 95% of cases. As serous tubal intraepithelial carcinomas (STICs) have been proposed to be the most likely precursor of HGSC, we undertook a study to determine whether STICs harbor TP53 mutations as well. Mutations of TP53 have been reported in STICs and associated HGSC but that study was limited to 5 cases. We therefore performed TP53 mutational analysis in a larger series of STICs and concurrent HGSCs and correlated the mutational status with p53 immunoreactivity.

Formalin-fixed paraffin-embedded tissue specimens were obtained from 18 HGSCs with concurrent STICs; 8 of them contained two discrete STICs. Approximately 1,000 cells from STIC and normal-appearing fallopian tubal epithelium were laser-capture microdissected, while HGSCs were manually microdissected. Genomic DNA was extracted, PCR amplified and sequenced. TP53 mutations were analyzed from exons 4 to 8. Immunohistochemistry (IHC) for p53 was performed in all the cases.

TP53 mutations were detected in 15 (83.3%) of 18 HGSCs. Importantly, TP53 mutations were not detected in the corresponding FTE samples from the same patients, confirming they are somatic mutations in HGSCs. STIC and associated HGSC shared identical TP53 mutations in 15 (93.8%) of 16 patients including 7 who had two STICs. The discordant case showed TP53 mutation in the HGSC but not in two separate concurrent STICs. By IHC, all the cases demonstrated the same pattern of p53 immunoreactivity (either all positive or completely negative) except the case with wild-type TP53 in the STIC and mutant TP53 in the HGSC. By IHC the STIC was p53 negative and the HGSC p53 positive. The three TP53 wild-type HGSCs and their associated STICs exhibited undetectable nuclear p53 by IHC. In contrast, four p53-negative HGSCs contained mutant TP53 with either a deletion or an insertion mutation.

Our findings provide cogent evidence that TP53 mutations occur in most STICs, and that both STIC and concurrent HGSC share the identical TP53 mutations in the majority of cases. Future molecular genetic studies are necessary to delineate the clonal relationship and tumor progression from STIC to HGSC.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 221. doi:10.1158/1538-7445.AM2011-221
Abstract 2233: Phage display selection of cancer-specific peptides on human bladder for molecular imaging of bladder cancer
Authors: Pan Ying , Volkmer Jens-Peter , Liu Jen-Jane , Wu Katherine , Mach Kathleen E. , Weissman Irving L. , Liao Joseph C.
Published: June 2012

Introduction and Objectives: Molecular imaging could transform cancer diagnosis by coupling existing imaging modalities with labeled tumor-specific antibodies or peptides. Current diagnosis of bladder cancer is by white light cystoscopy, which has suboptimal specificity for differentiating non-papillary cancer from inflammation. To identify bladder cancer-specific peptides, we applied phage display, an unbiased, combinatorial strategy in which up to 10⁁9 foreign peptides or proteins are individually expressed on bacteriophage to screen against cellular targets (biopanning). We report our effort to identify bladder cancer-specific peptides via biopanning with cystectomy specimens.

Methods: An M13 phage library displaying random linear heptapeptides was instilled into fresh cystectomy specimens (n=2). Non-specific phage were washed away and tumor was excised to extract tumor-bound phage, which were validated by bladder cancer cell line-based ELISA, flow cytometry, and immunofluorescence.

Results: Both bladders had high-grade urothelial carcinoma on pathology. 148 phage were obtained after 2 rounds of selection. 77 of these showed preferential binding to 2 bladder cancer cell lines (HT-1376, T24) by ELISA compared to negative control (insertless phage). 7 phage with >10-fold signals over the negative control were further validated with flow cytometry and immunofluorescence. By detecting cell-bound phage with fluorescently labeled M13 phage antibody, increased staining of T24 cells by all candidate phage compared to negative control was demonstrated by both flow cytometry (2-3-fold) and immunofluorescence. Peptides were sequenced for additional validation of tumor specificity with primary normal human urothelial and bladder tumor cells.

Conclusions: We have developed a technique for efficient biopanning of bladder cancer-specific peptides using whole cystectomy specimens. These peptides could serve as molecular contrast agents for targeted imaging with confocal laser endomicroscopy or fluorescent cystocsopy, and could potentially be utilized for targeted therapy. Compared to prior reports, which utilized cell lines and xenografts as biopanning targets, our approach offers a more clinically-relevant, efficient approach to identify peptides for cancer-specific imaging and therapy.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2233. doi:10.1158/1538-7445.AM2011-2233
Abstract 2237: Nelarabine is safe and effective in adult relapsed or refractory T cellacute lymphoblastic leukemia (T-ALL) and lymphoblastic lymphoma (T-LBL): The Bologna experience
Authors: Papayannidis Cristina , Iacobucci Ilaria , Abbenante Mariachiara , Lonetti Annalisa , Guadagnuolo Viviana , Ferrrari Anna , Ottaviani Emanuela , Curti Antonio , Paolini Stefania , Parisi Sarah , Clissa Cristina , Baccarani Michele , Martinelli Giovanni
Published: June 2012

Background. Nelarabine (N) is approved for the treatment of T-ALL and T-LBL that have not responded to or has relapsed after treatment with at least 2 chemotherapy regimens.

Aim. To evaluate safety profile and efficacy of N as savage therapy in 16 adult relapsed or refractory T-ALL or T-LBL.

Methods. After obtaining an informed consent, 16 patients (median age 33 years, range 19-45, M/F = 13/3) affected by T-ALL (n=10) and T-LBL (n=6) received savage therapy with N (median cycle=1, range 1-3), administered at standard adult dosage (1500 mg/sqm on days 1, 3 and 5, every 21). Four patients were primary resistant to induction treatment, 7 patients were relapsed after two previous chemotherapy regimens (including allogeneic BMT in 4 cases and autologous SCT in 1 case); the remaining 6 patients had a molecular relapsed disease (MRD positive). Molecular characterization was performed, including NOTCH and WT-1 genes mutational status. GEP analysis, according to Ferrando A. stratification (Cancer Cell 2002), is still ongoing.

Results. Currently, 12 out of 16 patients are evaluable, due to a too short follow up in the other 4 cases. Seven out of 12 patients obtained a complete remission (CR) (5 T-ALL 2 T-LBL);a partial remission (PR) was documented in 2 cases, with an overall response rate (ORR) of 75%. Median duration of CR was 10 weeks (range 2.8-54+). Among these, 2 out of 4 patients in molecular relapse reached a molecular CR and underwent an allogenic BMT (currently in CR after a median follow up of 12 months). Extra- hematological toxicity, not clearly related to the drug, occurred in 3 cases, determining, a complete and irreversible paraplegia, a condition of mental confusion, and a peripheral neuropathy, respectively.

Conclusions. N showed a strong efficacy also in cases with low levels of residual disease, in addition to a good safety profile. Neurological toxicity needs to be strictly monitored.

Acknowledgments. European LeukemiaNet, AIL, AIRC, Fondazione Del Monte di Bologna e Ravenna, FIRB 2006, PRIN 2008, Ateneo RFO grants, Project of integrated program (PIO), Programma di Ricerca Regione – Università 2007 – 2009.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2237. doi:10.1158/1538-7445.AM2011-2237
Abstract 2248: Oncogenic actions of HDGF (hepatoma-derived growth factor) in colorectal cancer: Implication for tumor biology/ patient prognosis and modulation by butyrate
Authors: Kudlich Theodor , Wilk Maike , Neun Tilmann , Hartmann Elena , Rogoll Dorothee , Luehrs Hardi , Rosenwald Andreas , Katzenberger Tiemo , Scheppach Wolfgang , Scheurlen Michael , Melcher Ralph
Published: June 2012

HDGF was identified as an oncogene relevant for colon cancer carcinogenesis by cDNA-array analysis, RT-PCR and immunohistochemistry. The analysis were performed in colonic adenoma (Geki2), carcinoma (HT29) and metastasis (SW620) cell lines, and in 50 colorectal cancer tissues and corresponding normal mucosa. By incubation of the cell lines with the short chain fatty acid butyrate (4mM), it was possible to (down-) regulate the HDGF-expression level. In the patients we analysed, HDGF overexpression was not associated with a worse prognosis or any other clinical parameter. To study the mechanisms of action of HDGF we stably transfected a HDGF-siRNA containing plasmid into HT29 colon carcinoma cells, resulting in a almost complete inactivation of HDGF-expression. This blocking leads to altered growth characteristics and cell differentiation and the cells exhibit potent pro-apoptotic properties. An affymetrix-expression array was performed and first results will me shown at the meeting. In conclusion, HDGF might be a potential therapeutic target for human colorectal cancer and a modulation of expression is possible by the short chain fatty acid butyrate. These findings may have major implications in the treatment of colorectal cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2248. doi:10.1158/1538-7445.AM2011-2248
Abstract 2250: PKR signaling pathway plays an important role in prognosis for non-small cell lung cancer
Authors: Pataer Apar , He Yong , Correa Arlene M. , Fang Bingliang , Roth Jack A. , Wistuba Ignacio I. , Swisher Stephen G.
Published: June 2012

The role of RNA-dependent protein kinase (PKR) in antiviral defence mechanisms and in cellular differentiation, growth, and apoptosis is well known, but the role of PKR in human lung cancer remains poorly understood. To explore the role of PKR in human lung cancer, we evaluated PKR's expression in tissue microarray specimens from both non-small cell lung cancer (NSCLC) and normal human bronchial epithelium tissue. The NSCLC cells showed lower levels of PKR expression than normal bronchial epithelium cells did. We also found a significant association between lower levels of PKR expression and lymph node metastasis. We found that loss of PKR expression is correlated with a more aggressive behavior, and that a high PKR expression predicts a subgroup of patients with a favorable outcome. Univariate and multivariate Cox proportional hazards regression models showed that a lower level of PKR expression was significantly associated with shorter survival in NSCLC patients. We further validated and confirmed that PKR to be a powerful prognostic factor in TMA-2 lung cancer (HR=0.22, P<0.0001). We also observed that the patients with high p-PKR or p-eIF2a expression had a significantly longer median survival than those with little or no p-PKR or p-eIF2a expression (P = 0.03 and P = 0.032, respectively). Combined expression of PKR and p-PKR or PKR and p-eIF2a increased patient survival (P = 0.001). Combined expression levels of PKR and p-PKR or p-eIF2a can be new markers for predicting the prognosis of patients with NSCLC.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2250. doi:10.1158/1538-7445.AM2011-2250
Abstract 2261: Prognostic significance of the low level microsatellite instability phenotype differs with race in colorectal adenocarcinoma
Authors: Katkoori Venkat R. , Salih Chura , Sthanam Meenakshi , Shanmugam Chandrakumar , Callens Tom , Messiaen Ludwine M. , Grizzle William E. , Bumpers Harvey L. , Birdsong George , Manne Upender
Published: June 2012

Purpose: Several studies have examined the prognostic value of microsatellite instability (low, MSI-L, and high, MSI-H) phenotypes in colorectal adenocarcinomas (CRCs), but none have specifically considered patient race/ethnicity to assess the value of MSI-L. Therefore, this study assessed the prognostic value of the MSI-L phenotype in African-American and non-Hispanic Caucasian (NHCA) CRC patients separately.

Experimental Design: CRCs from 276 African-Americans and 377 NHCAs, collected at the hospitals of the University of Alabama at Birmingham and Morehouse School of Medicine, were assessed for microsatellite instability and p53 mutational status (exons 4 through 9). MSI was assessed at 4 CA-dinucleotide MS loci (Mfd 27, Mfd 41, Mfd 47, and Mfd 57) and 2 poly-A repeats (BAT25, BAT26). Samples were considered MSI-H if at least 2 loci showed instability and MSI-L (low) if only 1 marker was unstable. The phenotypes were correlated with clinicopathologic features and patient survival by use of the χ2 test and univariate Kaplan-Meier analyses, respectively.

Results: The incidence of the MSI-L phenotype was higher in African-American patients (49 of 276, 18%) compared to NHCA patients (27 of 377, 7%). In contrast, the frequency of the microsatellite stable (MSS) phenotype was higher in CRCs of NHCAs (72%) than in CRCs of African-Americans (56%). In addition, the incidence of microsatellite instability-high (MSI-H) phenotype was similar in African-Americans (26%) and NHCAs (21%). Presence of the MSI-L phenotype significantly correlated with a higher incidence of missense p53 mutations (64%) and high-grade tumors (31%) and with advanced stages (III and IV) (67%) of CRCs in NHCAs. Such associations, however, were not found in African-American patients. For NHCA patients, CRCs with the MSI-L phenotype had significantly higher mortality (log-rank p=0.044) as compared to MSS or MSI-H. In contrast, for African-American patients, the MSI-L phenotype was associated with a better prognosis (log-rank p=0.043) compared to the MSS or MSI-H phenotypes.

Conclusions: These findings suggest that CRC with the MSI-L phenotype is associated with p53 mutations, high-grade tumors, and advanced tumor stage, and with short survival of NHCAs but not African-Americans. This work was supported by grants from the NCI/NIH (2U54-CA118948-03, R01-CA98932, and R03-CA139629).

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2261. doi:10.1158/1538-7445.AM2011-2261
Abstract 2264: K-ras mutations in colorectal cancer may predict a pattern of organ-specific metastasis
Authors: Garrido-Laguna Ignacio , Janku Filip , Falchook Gerald S. , Fu Siqing , Naing Aung , Wheler Jennifer , Tsimberidou Apostolia , Hong David S. , Kurzrock Razelle
Published: June 2012

Background: Activating mutations of the K-ras oncogene in colorectal cancer (CRC) are associated with resistance to EGFR antibodies and poor prognosis. We systematically analyzed clinical and pathological characteristics associated with K-ras mutations. Methods: Patients with CRC referred to the phase I program for targeted therapy were analyzed for K-ras mutations using PCR-based DNA sequencing. Patients with mutant K-ras were matched with wild-type (wt) K-ras controls. Multiple clinical and pathological characteristics were analyzed to determine, whether there is a phenotype associated with K-ras mutations. Results: A total of 151 patients with CRC were identified; 61 with K-ras mutations; 80 with wt K-ras and 10 with unknown K-ras status. Patients with K-ras mutations compared with wt K-ras had more frequently lung metastases (80% vs. 63%, p = 0.03). Patients whose tumors had K-ras mutations had higher number of metastatic sites of disease (3.18 vs. 2.65; p = 0.013). There were no associations between K-ras mutations and gender, age at diagnosis, liver metastases, peritoneal metastases, lymphatic involvement or Duke stage at diagnose. Patients with K-ras wt had a trend for longer median survival (283 vs. 222 weeks, p=0.09). There was no difference in the median survival from diagnosis in patients with different types of K-ras mutations (codon 12, codon 13, and codon 61). Dukes staging was the only statistically significant prognostic factor on multivariate analysis (p < 0.05). Conclusions: K-ras mutations in CRC in comparison with wt K-ras were associated with more frequent lung metastases and shorter survival.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2264. doi:10.1158/1538-7445.AM2011-2264
Abstract 2284: Investigation of notch-1, ErbB-2, and ERα crosstalk in breast cancer
Authors: Rogowski Allison S. , Osipo Clodia
Published: June 2012

Notch-1 is a breast oncogene that is overexpressed with its ligand Jagged-1 in human breast cancers-associated with the poorest overall survival. Notch signaling can be inhibited by a gamma-secretase inhibitor (GSI). We have recently determined that the estrogen receptor-alpha or ErbB-2 inhibits Notch-1 activation in breast cancer cells. In the current study, we sought to uncover the complex crosstalk between ER, ErbB-2, and Notch-1 and ask whether triple combination treatment can disrupt this complex cross-talk model to inhibit growth of ER positive breast cancer cells (MCF-7) and possibly prevent anti-hormone resistance. The results demonstrated that following 1 week of estrogen deprivation, MCF-7 cells develop resistance and regrow. Canonical Notch gene targets: Hes-1, Hey-1, Hes-5, and Deltex-1 are significantly increased at this 1 week time point. Similarly, ErbB-2 mRNA increased significantly after 72 hours of estrogen deprivation. Upon treatment with fulvestrant, a pure ant-estrogen, ER transcriptional activity as measured by PS2 mRNA is inhibited after one week. Interestingly, the combination of fulvestrant and lapatinib, an anti-ErbB-2 tyrosine kinase inhibitor, synergistically increased both Deltex-1 and ErbB-2 mRNAs which were reduced upon GSI treatment. Western blot analysis showed an increase in ER and tyrosine-phosphorylated ErbB-2 and total ErbB-2 proteins. This increase in protein expression was further increased upon dual treatment with fulvestrant and lapatinib. Conversely, treatment with a Notch inhibitor, GSI caused a decrease in both total and tyrosine-phosphorylated ErbB-2. Cell cycle analysis showed that fulvestrant treatment significantly growth arrested cells in G1 while decreasing cells in S-phase. However, lapatnib or GSI or the combination treatments did not further enhance the growth inhibitory effects of fulvestrant. Similar results were observed using Annexin-V analysis by flow cytometry as a measure of early apoptosis. These results suggest that while inhibiting ER and ErbB-2 simultaneously increases Notch activation in a synergistic manner, this dramatic increase in Notch activity in the short term does not sensitize ER positive breast cancer cells to a Notch inhibitor to undergo cell death.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2284. doi:10.1158/1538-7445.AM2011-2284
Abstract 2288: CYP3A4 monoxygenase regulates IGF-1 signaling in ER-positive breast cancer cells
Authors: Guo Zhijun , Mitra Ranjana , Milani Monica , Rodriguez Mariangellys , Yee Douglas , Sachdev Deepali , Potter David A.
Published: June 2012

Cytochrome P450 3A4 (CYP3A4) is an important monooxygenase that metabolizes a wide range of xenobiotics including many drugs and environmental chemicals, as well as endogenous substances such as steroids. Expression of CYP3A4 has been observed in breast tumors and has been associated with nodal metastases and decreased overall survival in breast cancer. To investigate roles of CYP3A4 on breast cancer progression and the mechanisms involved, we performed RNAi knock down studies, demonstrating that CYP3A4 regulates anchorage-dependent proliferation and clonogenicity of the MCF7 line. Unexpectedly, we found that stable CYP3A4 shRNA knock down MCF7 lines exhibited significant higher clonogenicity relative to the non-target control line in soft agar (P<0.05). Further investigation demonstrated that this increased clonogenicity is due to activation of IGF autocrine pathway, which could be abrogated by an antibody to the IGF1R. The PI3-Kinase inhibitor LY294002 abolished the increase of clonogenicty of CYP3A4 silenced lines, indicating the involvement of PI3-Kinase pathway. Phosphorylation of AKT protein is elevated in these lines, consistent with increased IGF-1 signaling. These results indicate that CYP3A4 may play a role in regulating IGF-1 signaling in ER-positive breast cancer cells. These results suggest that inhibition of CYP3A4 in combination with IGF1R function blocking antibody may have enhanced therapeutic efficacy compared to either modality alone.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2288. doi:10.1158/1538-7445.AM2011-2288
Abstract 2296: Identification of novel nuclear receptor targets in estrogen receptor negative breast cancer
Authors: Covington Kyle R. , Gu Guowei , Tsimelzon Anna , Hilsenbeck Susan , Brown Powel , Change Jenny , Osborne C Kent , Xu Jianming , O'Malley Bert , Mangelsdorf David , Minna John , Fuqua Suzanne
Published: June 2012

Introduction: Estrogen receptor (ER)-negative breast cancer has a particularly poor prognosis, and there are limited targeted agents for this subtype.

Aims and Methods: To identify nuclear receptor (NR) targets, we did microarray analysis of 227 ER-negative tumors as assessed by immunohistochemistry, and performed hierarchical clustering using 41 NRs, and prediction analysis of microarrays (PAM) across the clustered groups. Cell lines were matched to identified groups using previously published data. Clinical correlations were made using previously published breast cancer datasets.

Results and Conclusion: The 41 NRs clustered the tumors into 5 distinct groups. We found that the androgen receptor (AR) was the highest ranked discriminator of these groups followed by ERα. Group 1 (14% of the tumors) was characterized by elevated ERRα and RXR expression. Group 2 (9%) was characterized by higher expression of the orphan receptor NURR1. Group 3 was the largest group (37%), and showed high level expression of PPARα. Group 4 (16%) expressed higher levels of PPARγ. Group 5 (24%) demonstrated particularly high relative expression of AR, and also showed higher expression of ERα and ERRα. We used previously published microarray data to match cell lines to the NR groups using the scoring matrix developed in the PAM analysis. These cell lines are currently being tested for response to NR agonists and antagonists in growth (MTT, soft-agar, mammosphere) and apoptotic assays. We used a previously published microarray data set with long-term follow up information to identify potential differences in outcomes for the different NR subtypes. While we found no significant differences between the groups, the sample size was quite low for each subtype (n∼15 per group).

In summary, we have identified several novel ER-negative tumor groups by different expression level of NRs which may contribute to the prediction of breast cancer molecular subtypes.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2296. doi:10.1158/1538-7445.AM2011-2296
Abstract 2297: ERβ agonists reduce letrozole resistant breast cancer cell growth and diminish aromatase expression and activity
Authors: Ganapathy Manonmani , Nair Hareesh Babu , Kirma Nameer B. , Krishnegowda Naveen Kumar , Vadlamudi Ratna Kumar , Kurmayagari Kusuma , Tagliaferri Mary , Cohen Isaac , Tekmal Rajeshwar Rao
Published: June 2012

Aromatase inhibitors (AI) have shown efficacy against estrogen receptor (ER) positive breast cancer; however, development of resistance to AI is a major concern. The need to develop therapeutic agents that overcome AI resistance is urgent. We investigated whether synthetic and natural selective ERβ agonists restored sensitivity to AI and anti-estrogens in hormone resistant breast cancer cells. Our data suggest that ERβ agonists such as DPN (a synthetic compound) and plant derived Nyasol, Liquiritigenin, and MF101 (Menerba) ERβ agonists may restore sensitivity against resistance by the current drugs. Natural ERβ agonists in combination with AI reduced cell proliferation in MCF7/ARO (overexpressing aromatase), MCF7/HER2 (overexpressing Her2/neu) LTLT-Ca (letrozole resistant), MCF7/TAM (tamoxifen resistant), SKBR3, and T47D breast cancer cells by 70 % to 90% when compared with DPN/AI combination. Our Western blot and RT-PCR analyses showed that combination treatment with natural ERβ agonist in combination with AI resulted in decreased levels of ERα, Cyclin D1, TNF-α, IL-6 and increased ERβ levels in LTLT-Ca and MCF7/ARO cells. In addition, aromatase expression and activity were decreased due to ERβ agonists/AI combination treatment. The activity of aromatase promoter 1.3, which is activated in breast cancer, was found to be down regulated with Nyasol, Liquiritigenin and MF101 combinations with AI when compared to single compounds in various breast cancer cells. Decreased promoter 1.3 activity is consistent with the combination-treatment decrease in the expression of inflammatory cytokines known to induce this promoter (e.g., IL-6). Our data suggest that inhibition of aromatase expression/activity by natural ERβ agonists (in combination with AI) may be a factor in overcoming AI-resistant breast cancer cell growth by these drugs. Our data also suggest that modulation of inflammatory cytokines may be factors by which ERβ agonists may influence aromatase expression and sensitizing AI-resistant breast cancer to AI therapy. Further work is required to understand the mechanistic aspects of this regulation and to advance natural ERβ agonists to the clinical treatment of AI-resistant breast cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2297. doi:10.1158/1538-7445.AM2011-2297
Abstract 23: Prognostic significance of vitamin D receptor polymorphisms in head and neck squamous cell carcinoma
Authors: Hama Takanori , Norizoe Chihiro , Yuza Yuki , Suda Toshihito , Kato Takakuni , Moriyama Hiroshi , Urashima Mitsuyoshi
Published: June 2012

Objective Many studies demonstrate associations between UVB rays and a lower risk of developing various cancers, implying that UVB rays induce vitamin D synthesis, which suppresses growth and induces differentiation/apoptosis of cancer. In patients with non-small-cell lung cancer, vitamin D receptor (VDR) polymorphisms and haplotypes are reported to be associated with survival. We hypothesized that a similar association would be observed in other type of cancers. In this study, we focused on head and neck squamous-cell carcinoma (HNSCC).

Methods DNA was extracted from the frozen tumor and the VDR polymorphisms (Cdx2, FokI and BsmI) in 97 patients with HNSCC were genotyped by sequencing. Disease-free survival was compared between VDR polymorphisms using Kaplan-Meier survival with log-rank tests and using the Cox proportional hazard model adjusted for age, gender, primary tumor site, and postoperative stages. Adjusted hazard ratios (AHR) and 95% confidence intervals (95% CI) were determined.

Results Tumor recurrence occurred in 41/97 (42%) patients during a median follow-up of 603 days. Genotype frequencies of the VDR polymorphisms were as follows: FokI: C/C, 39 (40%); C/T, 48 (50%); TT, 10 (10%); for Cdx2: G/G, 16 (17%); G/A, 41 (42%); A/A, 40 (41%) Bsm I: A/A, 5 (5.2%); A/G, 16 (16.5%); and G/G, 76 (78.3%). The FokI T/T genotype was associated with poor prognosis: median survival for T/T was 265 days compared with 959 days for C/C or C/T (log-rank: P=0.015; AHR, 2.65; 95% CI, 1.18 to 5.96; P=0.018). In contrast, Cdx2 and BsmI showed no significant association with survival. The G-T (Cdx2-FokI) haplotype was associated with worse disease-free survival compared with other haplotypes: median disease-free survival for G-T was 238 days compared with 959 days for other haplotypes (log-rank: P=0.0008; AHR, 6.67; 95% CI, 2.23 to 20.0; P=0.001).

Conclusion These results suggest that VDR polymorphisms and haplotypes may be associated with prognosis of patients with HNSCC.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 23. doi:10.1158/1538-7445.AM2011-23
Abstract 2308: Selective targeting of HeLa cervical cancer cells using folate receptor targeting drug loaded PLGA-lipid hybrid nanoparticles
Authors: Sandoval Sergio , Liberman Alex , Yang Jian , Aschemeyer Sharraya , Alfaro Jesus G. , Zhang Liangfang , Trogler William C. , Kummel Andrew C.
Published: June 2012

The response rate of breast cancer to first line chemotherapies is encouraging, but 20-30% of patients develop chemoresistance to these drugs, and consequently, have a cancer reoccurrence 7-10 months after their last treatment. Chemoresistance is believed to be due to drug efflux proteins responsible for the removal of many commonly used anti-neoplastic agents. One possible way to overcome these drug efflux pumps is to give higher doses of chemotherapy, but high doses of such agents commonly lead to chemocytotoxicity. Targeted PLGA-Lipid hybrid nanoparticle (NP) drug delivery systems have been developed that can deliver high doses of chemotherapy agents specifically to breast cancer cells. A practical cancer targeting drug delivery system will reduce the overall amount of chemotherapy agents given to patients for a given amount of targeted NPs endocytosed by cancer cells. Biodegradable NPs were synthesized using a novel nano-precipitation lipid-polymer hybrid platform which also allows for the encapsulation of hydrophobic chemotherapy drugs within the NPs. Using this method, drug free NPs have been shown to have an average diameter size of 81.78 nm (PDI: 0.25), while single loaded NPs, with Paclitaxel or Doxorubicin, show an average size between 72.33 to 89.64 nm (PDI: 0.242 to 0.339), signifying that the synthesis technique creates consistent sub 100nm particles. The majority of all NPs show a zeta-potential value of > -30 mV consistent with the NPs having sufficient repulsive interaction to be mono-dispersed in solution under physiological conditions. Folate receptors are often over expressed on the surfaces of cancer cells; therefore, folic acid was incorporated to the surface of these NPs as a cancer targeting ligand. Previous studies have shown that HeLa cells, a cervical cancer cell line, over expresses folate receptors. Immunofluorescence studies show that folic acid coated PLGA-Lipid hybrid NPs are readily endocytosed by HeLa cells compared to non-targeted NPs. Cytoxicity studies will determine the increased effectiveness of drug delivery with targeted PLGA-Lipid hybrid NPs vs. untargeted PLGA-Lipid hybrid NP in cell lines and in animal models.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2308. doi:10.1158/1538-7445.AM2011-2308