bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 2113: Programmed cell death 4 (PDCD4) regulates apoptotic resistance of human gliomas
Authors: Liwak Urszula , Jordan Lindsay , Holcik Martin
Published: July 2012

Glioblastoma multiforme (GBM) is the most prevalent form of tumors of the central nervous system with an average survival rate of less than one year. Given the location and characteristics of GBM only limited treatment options are available, thus understanding the mechanisms of GBM formation or progression may lead to the development of novel treatment options. Strikingly, a common feature of GBM is the loss of expression of the tumor suppressor programmed cell death gene 4 (PDCD4), which correlates with a poor prognosis. Through both transcriptional and translational regulation, PDCD4 has been shown to regulate many proteins within the cell, although the precise mechanism of target selection is not known. We have hypothesised that silencing of PDCD4 in glioblastomas leads to an altered expression of apoptosis-regulating proteins resulting in the suppression of apoptotic signals and enhanced chemo-resistance of glioblastomas. Indeed, we show that low levels of PDCD4 correlate with an increase in the anti-apoptotic XIAP and Bcl-xL proteins, and decrease in pro-apoptotic Apaf-1. Importantly, these proteins are regulated at the level of protein synthesis through the internal ribosome entry sites (IRESs) in the 5’ untranslated region (UTR) of their respective mRNAs. IRES elements allow for translation to occur through a cap-independent mechanism during times of cellular stress when global translation is attenuated. We further show that PDCD4 regulates the activity of Bcl-xL, XIAP and Apaf-1 IRES and is therefore an IRES specific translational regulator. We further dissect the signalling pathways that regulate PDCD4 levels and show that activation of S6K2 results in the proteolytic degradation of PDCD4 and concomitant upregulation of XIAP and Bcl-xL, and downregulation of Apaf-1 levels. Importantly, reintroduction of PDCD4 into glioblastoma cell lines results in a reduction in both XIAP and Bcl-xL protein levels and enhanced cell death. In summary, our work provides a novel role for PDCD4 as a translational regulator of XIAP, Bcl-xL and Apaf-1, as well as a mechanistic understanding into the regulation of PDCD4 expression. Our research offers insight into the biology of glioblastomas in the hopes that we can identify new pathways as novel targets for anticancer 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 2113. doi:10.1158/1538-7445.AM2011-2113
Abstract 2117: The Wnt inhibitory factor 1 (WIF-1) has tumor suppressing functions in glioblastoma potentially by inducing cellular senescence
Authors: Vassallo Irene , Lambiv Wanyu , Delorenzi Mauro , Shay Tal , Diserens Annie-Claire , Misra Anjan , Feuerstein Burt , Murat Anastasia , Migliavacca Eugenia , Hamou Marie-France , Domany Eytan , Stupp Roger , Hegi Monika E.
Published: July 2012

Glioblastoma multiforme is the most aggressive form of human glioma and despite recent progress in therapy the prognosis remains dismal with a median survival of 15 months. Expression based prediction of gene alterations identified Wnt inhibitory factor I (WIF1) as a new candidate tumor suppressor gene involved in glioblastoma. WIF1 encodes a secreted Wnt antagonist and it was strongly down-regulated in most glioblastoma as compared to normal brain, implying deregulation of Wnt signaling. Silencing of the WIF1 gene was found to be mediated by deletion and WIF1 promoter hypermethylation. Ectopic expression of WIF1 in glioblastoma cell lines revealed a dose dependent decrease of Wnt pathway activity. To further dissect the biological effects of WIF1 re-expression, we established WIF1 overexpressing glioblastoma cell lines. We observed that WIF1 re-expression inhibited cell proliferation in vitro and strongly reduced anchorage independent growth. The ability of forming colonies in soft agar was reduced to less than 11% of the control. Moreover, the expression of WIF1 was able to completely abolish tumorigenicity in a respective xenograft model in nude mice. Interestingly, WIF1 overexpression in glioblastoma cells induced a senescence-like phenotype characterized by the appearance of enlarged flattened and multinucleated cells positive for the presence of β-galactosidase, a late marker of senescence. These results provide evidence that WIF1 has tumor suppressing properties in glioblastoma, hence, the implication of a deregulated Wnt pathway may render glioblastoma sensitive to Wnt signaling inhibitors, potentially by diverting the tumor cells into a senescence-like state.

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 2117. doi:10.1158/1538-7445.AM2011-2117
Abstract 2128: Salvianolic acid B inhibits both ER-α +/- breast cancer cell growth in vivo and in vitro
Authors: Sha Wei , Gu Xinbin , Guo Yinhan , Wang Paul , Sukumar Saraswati , Zhou Yanfei
Published: July 2012

PURPOSE: Estrogen receptor α negative (ER-α/-) breast cancer cells are found to respond poorly to chemotherapeutic agents. Salvianolic acid B (Sal-B) is an active depside compound isolated from Salvia miltiorrhiza Bge, which is a well-known Chinese medicine that has been widely used to treat various disorders including cancers. In this study, we evaluated the anti-cancer activity of Sal-B leading to ceramide-mediated apoptosis in ER-α + and ER-α – cancer cell lines. DESIGN METHODS: Using MCF-7-luc (ER-α/+) and MDA-MB-231-luc (ER-α/-) human breast cancer cell lines as a test model, cell-based bioluminescence assay and colony assay for cell viability, Western Blot analysis for ER-α and apoptosis-related proteins expression, flow cytometry analysis for cell cycle, and tumor xenografts were performed. RESULTS: Significant decreased cell viabilities (p<0.05) were observed in Sal-B treated ER-α + and ER-α – cells. The expression of anti-apoptotic proteins (Bcl-2, Bcl-XL and surviving) and ceramide metabolism enzymes (GCS and GM3 synthase) all markedly decreased. Sal-B treatment suppressed cell cycle related protein expression, such as cyclin A and B. Further analysis using flow cytometry confirmed these observations. The tumor size was significantly lower in Sal-B treated MDA-MB-231-luc cells transplanted mice group compared to untreated control group and doxorubicin treated group. CONCLUSION: Sal-B effectively inhibits the growth of cultured ER-α +/- cell lines and MDA-MB-231-luc tumor xenografts. In addition, Sal-B is able to modulate ceramide-mediated apoptosis by inhibiting ceramide metabolic enzymes (GCS and GM3 synthase). Thus, Sal-B has high potential to be a new therapeutic strategy to improve ER-α/- cancer treatment. Research supported in part by grants P20 CA118770 and U54 CA091431 from NCI/NIH and 2G12 RR003048 from the RCMI Program/NCRR/NIH.

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 2128. doi:10.1158/1538-7445.AM2011-2128
Abstract 2132: Deferoxamine and Deferasirox enhance anticancer effects of apoptosis in gastric cancer cells
Authors: Oh Go Oun , Kang Myoung-Hee , Kang Han-Na , Kim Jung-Lim , Kim Jun-Suk , Oh Sang-Cheul , Yoo Young-A Yoo , Lee Seung-Young Lee
Published: July 2012

Deferoxamine(DFO) and Deferasirox(DFRA) is an iron chelating agent that has been used extensively to treat acute iron detoxification and chronically iron overloaded patients. Recent reports have been shown that iron chelators induce anti-proliferative effect in multiple leukemia cells. However, their roles and the underlying mechanism in anti-tumorigenic function of solid tumor, especially gastric cancer, are not yet known. In this work, we evaluated the anti-tumorigenic action of these two iron chelating agent with gastric cancer cell line, and investigated their apoptosis-inducing effects as the potential mechanism in this process.

The results show that both of them induce the growth inhibitory effects in both dose- and time-dependent fashion in gastric cancer cell line AGS and SNU-638. Cell cycle analysis by FACS indicated that both DFO/DFRA-treated cell lines showed an increase in the proportion of cells in sub-G1 phase, compared to untreated cells. Exposure of gastric cancer cells to DFO/DFRA also resulted in the increase in the percentage of annexin V- positive and PI-negative cells. The results by multiple in vitro experimental model, showed that DFO /DFRA induce these gastric cancer cells to undergo apoptosis with a release of cytichrome C from mitochondria, the activation of caspase-3/9, the cleavage of PARP, the cleavage of anti-apoptotic protein Bcl-2, together with the accumulation of pro-apoptotic protein Bax and Bim. Furthermore, knock-down of Bax and Bim expression by RNA interference virtually eliminated DFO/DFRA-induced apoptosis. Importantly, inhibition of JNK kinase activity demonstrated that DFO/DFRA-induced apoptotic pathway was regulated by the JNK signaling cascade

In conclusion, this finding indicates that iron-chelating agent, DFO and DFRA, promotes apoptosis of gastric cancer cells by sequential activation of the JNK signaling pathway followed by the up-regulation of intrinsic pathway of Bax/Bim-caspase 3/9.

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 2132. doi:10.1158/1538-7445.AM2011-2132
Abstract 2133: Phenylenebis(1,2-ethanediyl)bisisoselenourea (PBISe), a novel selenium drug for the treatment of hepatocellular cancer (HCC)
Authors: Tagaram Hephzibah R. , Desai Dhimant , Ongsansoy Sherwin , Dasari Anthia P. , Gowda Kavitha , Liu Dai , Liu Guangfu , Amin Shantu , Staveley-O'Carroll Kevin
Published: July 2012

Hepatocellular cancer (HCC) is an aggressive tumor that frequently arises in a setting of chronic liver disease and cirrhosis. Appearing 20 to 30 years from initial insult, it is more likely to be discovered in its late stage. The median survival following diagnosis is approximately 6 to 20 months. Although the definitive treatment is tumor resection, most patients are not eligible because of tumor extent or underlying liver dysfunction. Alternative chemopreventive approach in reducing HCC mortality is to be explored. Earlier we have shown the efficacy of PBISe against colon adenocarcinoma and metastatic melanoma with a negligible systemic toxicity in animal studies. In the present study, we intend to demonstrate the chemotherapeutic effects of PBISe on the human HCC. We analyzed the role of PBISe and the underlying mechanism in HCC. PBISe in our study suppressed cell growth, and induce apoptosis. Evaluation of PBISe was performed in vitro on human SK-HEP-1, HepG2, C3A and HUH-7 cells by cellular viability, caspase 3/7 activity, annexin-V expression, DNA fragmentation by Tunnel, cell cycle analysis and AKT, ERK, STAT, SAPK/JNK phosphorylation. PBISe promotes apoptosis by upregulating caspase 3/7, annexin-V, and cPARP. Increased DNA fragmentation was observed with PBISe in all the HCC cell lines tested. PBISe also mediated the cellular proliferation by AKT signaling and downstream pPRAS40 by inducing the cell cycle arrest at G2-M phase. Decreased pERK, pSTAT and pAKT shows that PBISe has a potential to target several signaling pathways. Overall our results suggest that PBISe is a potent chemotherapeutic agent with novel properties for the treatment of HCC. The chemotherapeutic effect of PBISe in the murine HCC model will be discussed. Supported by Penn State Deans Feasibility Grant to H.R.T, NIH RO3 CA 137763-01 to D. D., NIH KO8 417-67HY to K.S.O.C.

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 2133. doi:10.1158/1538-7445.AM2011-2133
Abstract 2138: Vinblastine acutely sensitizes hematopoietic cancers to Bcl-2 targeting drugs
Authors: Bates Darcy J.P , Lowrey Christopher , Eastman Alan
Published: July 2012

Chronic lymphocytic leukemia (CLL) characteristically maintains high levels of the anti-apoptotic protein Bcl-2, thus protecting them from apoptotic death and leading to an accumulation of mature resting B cells. Many other hematopoietic malignancies including acute promyelocytic leukemia (APL) also depend upon Bcl-2 family proteins for survival, suggesting that Bcl-2 proteins are excellent targets for anti-cancer therapies. We have previously shown that some leukemia and lymphoma cell lines undergo rapid apoptosis (≤6 h) when incubated with the microtubule disrupting agent vinblastine. Several other cell lines undergo this rapid apoptosis when vinblastine is combined with various approaches that target the anti-apoptotic proteins Bcl-2 or Mcl-1. These approaches include incubation with ABT-737 that inhibits Bcl-2 and Bcl-X, and SCH727965 (dinaciclib) that inhibits CDK7/9, thereby inhibiting translation which results in rapid loss of Mcl-1. In this study, we have assessed the ability of these agents alone or in combination to induce apoptosis in freshly isolated CLL and APL cells. Incubation with vinblastine alone induced variable apoptosis within 6 h (5-60%). ABT-737 induced rapid and almost complete apoptosis in CLL and in 50% of APL cells ex vivo. However, when combined with vinblastine, a 10-fold lower concentration of ABT-737 was required to induce complete apoptosis. Dinaciclib alone also induced variable levels of apoptosis (5-90%), but again the combination with vinblastine induced extensive apoptosis at lower concentrations of both drugs. Normal peripheral blood mononuclear cells were resistant to single agent or combination treatments. Sensitivity to ABT-737, dinaciclib or vinblastine was independent of CD38 and ZAP70 status and previous clinical treatment (untreated or relapsed patients). These results suggest that combinations of vinblastine and ABT-737 or dinaciclib are more effective than single agent therapy. Furthermore, these combinations may overcome resistance to individual drug therapies in patients with CLL or APL.

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 2138. doi:10.1158/1538-7445.AM2011-2138
Abstract 2140: Assessment of curcumin-induced apoptosis and detection of cancer stem cell-like subpopulations in human esophageal cancer cell lines
Authors: Al Manaa Taghreed N. , Geusz Michael E. , Jamasbi Roudabeh J.
Published: July 2012

Curcumin, the major active ingredient of turmeric, has been shown to kill several types of malignant cells while it has little or no effect on normal cells, suggesting that it may be an effective therapeutic agent. Although some studies have investigated curcumin effects on esophageal cancer cell lines, no studies have characterized the curcumin-surviving cells, an important population that might show resistance to curcumin. There is increasing evidence that many cancers contain subpopulations that display stem cell characteristics. Cancer stem cells (CSCs) appear to play a central role in tumorigenesis, recurrence, metastasis, and resistance to cancer therapy. The aims of the current study were to assess curcumin-induced cell death and detect CSC subpopulations in six human esophageal cancer cell lines (TE-1, TE-8, KY-5, KY-10, YES-1, and YES-2). Aldehyde dehydrogenase-1A1 (ALDH1A1) expression was used as one marker for CSCs. To evaluate curcumin effects, the cell lines were exposed to 20-80 µM of curcumin for 30 hrs. In all six lines, cell death increased continuously with increasing dosage of curcumin based on a standard crystal violet assay. No cells survived at 80 µM, and the range of cell death across the six cell lines was 66 to 89% at 60 µM. To characterize the progeny of cells that survived curcumin, 1×105 cells from each line were exposed to 40-60 µM curcumin for 30 hours, and the colonies that formed from surviving cells were counted. The number of colonies present after 60 µM treatment varied between the cell lines (ranging from 8 to more than one hundred). The Yes-2 cell line did not survive at 60 µM, but produced 15 colonies after 40 µM treatment. Staining with an antibody against ALDH1A1 was used to compare CSC-like subpopulations within and among the original cells lines as well as cell lines established from the curcumin-treated lines. All cell lines were heterogeneous with respect to ALDH1A1 staining, revealing two subpopulations within each line. The intensity of staining was at least two times higher in the population considered to be CSCs. Interestingly, the curcumin-surviving cell lines showed a significant loss in the high-staining population compared to the untreated cells (T-test, p<0.05), suggesting that curcumin not only can kill cancer cells but also CSCs. Thus, esophageal CSCs appear to be highly sensitive to curcumin. Therefore, curcumin may be a more effective compound for esophageal cancer therapy than other chemotherapeutic agents.

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 2140. doi:10.1158/1538-7445.AM2011-2140
Abstract 2141: The differential apoptotic responses of normal breast cells versus luminal and triple negative breast cancer cells to chemotherapeutic agents
Authors: King Jamie L. , Gurley Kashenya M. , Rorie Checo J.
Published: July 2012

Triple negative breast cancer is characterized by the loss or low expression of estrogen receptor, progesterone receptor, and HER2 proteins which have been targeted and established as somewhat effective therapy regiments in other breast cancer subtypes including luminal tumors. Since triple negative tumors are missing these established drug targets, there has been little advancement in the establishment of targets in this breast cancer subtype. Triple negative breast cancer is described as aggressive due to their invasiveness and metastatic properties. One potential mediator of triple negative breast cancer aggressive behavior may be due to the fact this breast cancer subtype may have as high as an 80% p53 tumor suppressor gene mutation rate. While p53 may be mutated at high rates, it may be possible to design drugs to target some of the downstream genes that p53 transactivates, including the cyclin dependent kinase inhibitor p21 and the pro-apoptotic gene PUMA, in order to inhibit the further growth of the triple negative breast cancer cells. Here, we stressed a normal breast cancer control, luminal subtype, and triple negative subtype cancer cell lines with Actinomycin D, doxorubicin, and staurosporine. We show that all cell lines responded to the various DNA damaging agents via apoptosis as observed by light microscopy and by PARP cleavage using Western blot analysis. Interestingly, the “normal” breast cell line, AG1132, showed a delayed apoptosis response to doxorubicin treatment as compared to the breast cancer cell lines, HCC1806, HCC70, and HCC1500. We are monitoring the p53 tumor suppressor pathway network in all of these cells to determine its integrity and whether there is a direct or indirect involvement of p53 on the apoptosis responses. We are also further analyzing the chemotherapeutic agents to determine their effectiveness in killing breast cancer cells with limited cytotoxic effects to normal breast cells.

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 2141. doi:10.1158/1538-7445.AM2011-2141
Abstract 2144: Characterization of HMGB1-induced cell death in colon carcinoma cells
Authors: Gdynia Georg , Keith Martina , Schirmacher Peter , Roth Wilfried
Published: July 2012

The danger protein HMGB1 induces a distinct form of cell death in cancer cells which is different from classical necrosis, apoptosis, autophagy, or senescence. Interestingly, colon carcinoma cells are less sensitive for the cytotoxic activity of HMGB1 than other types of cancer cells. The aim of this study was to characterize the molecular and metabolic pathways regulating the susceptibility to HMGB1 in colorectal carcinoma. Stable ectopic over-expression of HMGB1 inhibited significantly the proliferation of colon carcinoma cells. Treatment of cells with recombinant human (rh) HMGB1 induced significant cytotoxicity in a concentration range of 80 – 200 nM. Cancer cells depleted of mitochondrial DNA were less susceptible to the cytotoxic effects of rhHMGB1. In ATP luciferase assays, after 72 h of incubation with rhHMGB1 a significant depletion of intracellular ATP was observed, paralleled by the formation of giant mitochondria. RhHMGB1 modulated the specific activity of the mitochondrial respiratory enzymes and the electron flux in the electron transport chain in a dose-dependent manner. Interestingly, addition of NAD+, L-pyruvate, or ATP did not protect the cells from rhHMGB1-induced cell death. RhHMGB1-induced mitochondrial and metabolic events were further characterized by tracking radioactive glucose and pyruvate isotopes. In summary, the HMGB1 protein induces a novel form of cell death in diverse types of cancer cells. In colon cancer cells, HMGB1 modulates the activity of the mitochondrial respiratory enzymes leading to a change in glycolytic flux and a strong depletion of intracellular ATP. These observations implicate a new functional link between the HMGB1 protein and mitochondrial respiratory regulation as well as glycolysis activity in cancer cells.

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 2144. doi:10.1158/1538-7445.AM2011-2144
Abstract 2145: AR-42, a novel histone deacetylase inhibitor with selectivity against leukemia stem cell via apoptosis induction, inhibition of chaperone function of heat shock protein 90 in acute myeloid leukemia
Authors: Yang Neng , Hassane Duane C. , Balys Marlene , Corbett Cheryl A. , Jordan Craig T. , Guzman Monica L.
Published: July 2012

AML is a fatal disease where most patients relapse and die of their disease. Increasing evidence indicates that disease relapse is driven by leukemia stem cells (LSCs). Thus, it is imperative to identify new therapies that can ablate LSCs. We have previously reported that screening the NCBI Gene Expression Omnibus (GEO) can accelerate the identification of anti-LSC compounds by searching for those mimicking the gene expression pattern of a known anti-LSC compound, parthenolide (PTL). One of our “hits” was the HDACi, AR-42 (Arno Therapeutics, Inc). This compound represents a novel class of HDACis that are structurally similar to phenylbutyrate, but with improved HDACi activity at sub-micromolar concentrations.

At first, we investigated effects of AR-42 on growth and colony forming ability by using AML cell lines and primary human AML samples. AR-42 exhibits low micromolar potency in biochemical and cellular assays. AR-42 efficiently suppressed AML cell growth at a low dosage (1 μM) after 24 hours of treatment. Just like PTL, AR-42 preferentially targets AML progenitor and stem cell populations. More than 50% cell death was induced by AR-42 in phenotypically defined AML stem / progenitor. Colony forming capability of LSCs treated with 1 μM AR-42 for 24 hours was significantly diminished. Furthermore, 1 μM AR-42 significantly impaired the potential of LSCs in a nonobese diabetic/severe combined immunodeficient (NOD/SCID) xenograft model.

Surprisingly, even though AR-42 partially mimics the gene expression pattern of PTL, it does not activate Nrf2-controlled cytoprotective responses like PTL. AR- 42 inhibits NF-κB but, unlike PTL, does not activate HMOX-1. AR-42- mediated apoptosis is associated with activation of caspase 8, PARP cleavage. Further studies found that AR-42 induced inhibition of HSP90 in conjunction with degradation of FLT3 protein. Altogether, these findings indicate that AR-42 may be a promising LSC-targeted therapeutic agent.

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 2145. doi:10.1158/1538-7445.AM2011-2145
Abstract 3906: Gene expression profiling of ductal carcinoma in situ reveals novel alterations in the tumor and stromal compartments related to progession and outcome of invasive breast cancer
Authors: Witkiewicz Agnieszka K. , Ertel Adam , Kline Jessica , Davicioni Elai , Knudsen Erik S.
Published: July 2012

An increasing number of women are diagnosed with ductal carcinoma in situ (DCIS). DCIS is non-obligate precursor to invasive breast cancer. Mechanisms leading to development and progression of DCIS to invasive breast cancer (IBC) are still largely unknown. When DCIS and IBC coexist in the same lesion, their transcriptional profiles are nearly identical; however, there are very few studies investigating gene expression in pure DCIS. The goal of this study was to compare gene expression profiles of microdissected epithelial and stromal components of pure DCIS and IBC. Epithelium and stroma were laser microdissected from 10 cases of pure DCIS and 10 invasive breast carcinomas. DCIS and IBC were matched with regard to estrogen, progesterone receptor and HER2 expression. Gene expression was analyzed using Affymetrix Human Exon 1.0 ST microarrays. Analyses of gene expression in IBC and DCIS revealed a number of differentially expressed genes in the epithelial (n=211) and stromal (n=143) LCM obtained cells. In the epithelial compartment many of the genes specifically associated with IBC are part of previously described epithelial to mesenchymal transition, metastasis and myoepithelial cell gene expression signatures. Consistent with these findings, gene ontology analyses found overrepresentation of GO Biological Process terms such as ‘cell adhesion’ (44 genes, p = 1.47E-14), ‘extracellular matrix organization’ (16 genes, p = 3.46E-09), ‘skeletal system development’ (22 genes, p = 5.87E-07) and ‘vasculature development’ (14 genes, P = 4.56E-03). Applying differentially expressed epithelial genes to a larger invasive breast cancer dataset showed association with decreased metastasis free and progression free survival.

Our study reveals that pure dcis and invasive breast cancer are distinct at the transcriptome level. Future work will show if genes differentially expressed between IBC and pure DCIS may be useful for identifying at the time of diagnosis DCIS patients likely to progress to IBC.

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 3906. doi:10.1158/1538-7445.AM2011-3906
Abstract 3908: Genomic profiling of gastric carcinoma in situ and adenomas by array-based comparative genomic hybridization
Authors: Tsukamoto Yoshiyuki , Uchida Masahiro , Noguchi Tsuyoshi , Uchida Tomohisa , Hijiya Naoki , Nakada Chisato , Matsuura Keiko , Murakami Kazunari , Fujioka Toshio , Moriyama Masatsugu
Published: July 2012

Although genomic copy number aberrations (CNAs) of gastric carcinoma at the advanced stage have already been extensively characterized by array comparative genomic hybridization (array CGH) analysis, those of gastric carcinoma in situ (CIS) are still poorly understood. Furthermore, no reports have demonstrated correlations between CNAs and histopathologic features of gastric adenoma. In this study, we investigated CNAs of 20 gastric CISs (Vienna category 4.2), 20 adenomas including 7 low-grade adenomas (LGA; Vienna category 3) and 13 high-grade adenomas (HGA; Vienna category 4.1), using oligonucleotide-based array CGH. The most frequent aberrations in CIS were gains at 8q (85%) and 20q (50%), and losses at 5q (50%) and 17p (50%), suggesting that these CNAs are involved in the development of CIS. We found that the pattern of CNAs in HGA was quite different from those in LGA. The most frequent CNAs in HGA were gain at 8q (62%) and 7pq (54%), whereas those in LGA were gain at 7q21.3-q22.1 (57%) and loss at 5q (43%). Interestingly, gains at 8q and 7pq, both of which occurred most frequently in HGA, were not detected in any cases of LGA. Of note, 8q gain was detected most frequently in both HGA and CIS but undetected in LGA. Since HGA is believed to have a higher risk of progression to invasive carcinoma than LGA, these data suggest that 8q gain is important for the malignant transformation of gastric adenoma.

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 3908. doi:10.1158/1538-7445.AM2011-3908
Abstract 3913: Establishing a genomic profile of four gastric carcinoma cell lines using array CGH, FISH and cytogenetic analyses
Authors: Lu Xianglan , Hallford Gene , Wang Xianfu , Li Shibo , Lee Ji-Yun
Published: July 2012

Four gastric carcinoma cell lines (CRL-1739TM, CRL-5822TM, CRL-5971TM and CRL-5973TM), established in the 1970s and 1980s, were purchased from ATCC. These cell lines have been distributed throughout the world and are regularly used for biomedical research. Cytogenetic information is available for three of these cell lines, and two of the three are known to have complex chromosomal rearrangements, though these have not been well characterized. In part, this is due to the complexity of chromosomal changes and the limited ability of G-banded chromosome analysis. Establishing a genomic profile of these cell lines is vitally important, so that their genotypes and phenotypes can be compared. In the current study, G-banded chromosome analysis, array CGH and FISH analyses were performed on these 4 cell lines. The G-banded chromosome analysis was performed and followed by array CGH using 720k oligonucleotide based array chip. The imbalanced regions and chromosome rearrangements, detected by G-banded chromosome and array CGH analyses, were confirmed by FISH using the appropriate DNA probes. Based on the combined data generated by these assays, we established genomic profiles of each cell line; deletions, duplications, translocations and insertions and a chromosomal homogenous staining region. Deletions of 3p and 18q, duplication of 8q, 19q and extra chromosome 20 were found to be common. These findings are consistent with array CGH analyses of fresh gastric tumor samples (data to be presented separately). The results of this study are important as they will provide important information on the status of genomic profiles, allow the expression patterns of gene(s) to be compared, and provide a mechanism for monitoring the genomic changes in these cell lines. This information, we believe, will allow laboratories to make more informed decisions about the need for replacing existing cell lines due to changes in their biological characteristics.

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 3913. doi:10.1158/1538-7445.AM2011-3913
Abstract 3915: α-Fetoprotein-producing hepatoma cells have increased Jagged1 gene copy numbers and their growth can be suppressed by gamma secretase inhibitor
Authors: Kawaguchi Kazunori , Honda Masao , Yamashita Taro , Takatori Hajime , Ueda Teruyuki , Kanno Masataka , Kaneko Shuichi
Published: July 2012

Background: Approximately 70% of patients with hepatocellular carcinoma (HCC) have abnormally high α-fetoprotein (AFP) levels, which increase with tumor progression and angiogenesis. We previously used cDNA microarray comparative genomic hybridization (aCGH) to demonstrate an association between hepatoma AFP-producing status and genomic copy number gain and loss. Although genomic copy number change is reported to be associated with some oncogenic factors, its relationship with molecular pathway aberration has not been elucidated. Here, we examined whether signal pathways are associated with both expression and genomic gain for the purpose of discovering clinically useful molecular targets in hepatoma patients.

Method: Changes in DNA copy number of hepatoma cells were analyzed using bacterial artificial chromosome (BAC)-aCGH and compared with gene expression profiles. Candidate genes were identified, and real-time PCR was used to confirm gene expression changes in AFP-producing cells. siRNA was used to inhibit gene expression and the effect of this on hepatoma cell growth was determined. Confirmation of genomic alteration was performed by real-time PCR on clinical HCC samples. Growth of hepatoma cells was examined following the application of an inhibitor of the identified signal transduction-related gene.

Results: The BAC clone was significantly amplified in some regions of chromosome 20p from hepatoma cells. This amplified region included the ligand for Notch signal transduction, Jagged1, which was shown to be up-regulated by microarray analysis and real-time PCR in AFP-producing hepatoma cells. Surgically treated AFP-up-regulated HCC samples were used to demonstrate the significant correlation between AFP and Jagged1 gene expression. Interestingly, tissue Jagged1 genomic gain and AFP expression were also correlated. The suppression of Jagged1 using siRNA in an AFP-producing cell line significantly repressed cell growth compared with an AFP-negative cell line. The inhibitor of the Notch pathway, gamma secretase inhibitor (GSI), is currently undergoing clinical trials for the treatment of Alzheimer's disease, and its effectiveness has been shown as a cancer therapy for solid tumors. Here, continuous application of GSI to hepatoma cells resulted in a significant suppression of cell growth.

Conclusion: The genomic amplification of Jagged1 contributes to the continuous mRNA expression that activates the Jagged1-Notch signaling pathway in hepatomas. GSI may be a promising candidate for use in the therapy of AFP-producing advanced HCC.

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 3915. doi:10.1158/1538-7445.AM2011-3915
Abstract 3916: PML nuclear bodies are juxtaposed to DNA-DSBs following IR-induced DNA damage
Authors: Tse Kenneth Chor Kin , Harding Shane M. , Zafarana Gaetano , Ahmed Kashif , Dellaire Graham , Bazett-Jones David , Bristow Robert G.
Published: July 2012

The promyelocytic leukemia (PML) tumor suppressor protein aggregates in discrete PML nuclear bodies (PML-NBs) that are detectable by immunofluorescent microscopy. PML-NB number can change in response to cell cycle and various cell stresses, including DNA damage. Intra-nuclear γH2AX foci form following ionizing radiation (IR) as a function of dose and time and are used as an indicator of DNA double strand breaks (DNA-DSBs). However, whether PML-NBs are associated with exogenous or endogenous (e.g. DNA replication associated) damage was unclear.

Using G0-G1 synchronized human fibroblast (GM05757) to exclude endogenous DNA damage, we examined the intra-nuclear locales of γH2AX and other DNA repair biomarkers with respect to PML-NBs following IR. PML +/+ and -/- MEFs did not vary in DNA-DSB repair based on comet assay. Consistent with this, PML-NBs did not respond to immediate DNA damage. However, 3D-confocal microscopy studies showed that PML-NBs associated with the majority of residual γH2AX sites at later times (24h post-IR). Using quantitative microscopy, these associations were distinguishable as juxtaposition and not true co-localization (i.e., between γH2AX and DSB marker 53BP1). Continued presence of damage sensing and signaling proteins (MRE11, NBS1, MDC1 and 53BP1) and persistent kinase activity (DNA-PK, ATM, CHK2) was observed at these residual γH2AX sites. Absence of RAD51 and BRCA1 indicated that these were not replication-associated breaks and the exclusion of TRF2 suggested that these were not telomeric regions; rather PML-NBs associated specifically with unrepaired exogenous DSBs. Residual γH2AX sites were not enriched in eu- or heterochromatin. Interestingly, scanning electron imaging revealed a lower chromatin density near residual γH2AX foci, suggesting chromatin remodeling in the vicinity of unrepaired breaks. Live cell experiment using GFP-PML IV and mCherry-53BP1tudor domain suggested that PML-NB mobility facilitated the association with residual 53BP1 foci. Our data suggests that maintenance of genomic stability may depend, in part, on the association between PML-NBs and residual γH2AX foci.

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 3916. doi:10.1158/1538-7445.AM2011-3916
Abstract 3918: Haploinsufficiency of MRE11A reduces DNA repair capacity in bronchial epithelial cells in response to Bleomycin and BPDE
Authors: Liu Yanbin , Tenent Ivo , Willink Randy , Leng Shuguang , Dagucon Christopher , Belinsky Steven A.
Published: July 2012

Reduced DNA repair capacity (DRC) and polymorphisms in genes involved in the requisite repair pathways are associated with increased risk for lung cancer and promoter hypermethylation. A SNP (rs7117042) was identified in MRE11A that resulted in a 30% reduction in gene transcription and was associated with promoter methylation in sputum from cancer-free smokers. In vitro studies have also demonstrated that formation of DNA double strand breaks (DSB) can lead to gene promoter methylation. The purpose of this study was to identify genes in the DSB repair pathway that may be rate limiting for DNA repair in response to DNA damage and ultimately assess their effect on transformation and promoter methylation. A model for haploinsufficiency was created to simulate germ line sequence variation in the MRE11A, NBS, and XRCC3 gene by shRNA stable knockdown in immortalized human bronchial epithelial cells (HBEC2 and HBEC13). The clones with 50% and 75% knockdown of target genes were selected and cell lines were exposed to increasing doses of bleomycin and BPDE respectively with DRC determined by formation of micronuclei. MRE11A knockdown reduced DRC by 2- and 2.5-fold following exposure to BPDE and bleomycin, respectively compared to parental cell lines. DRC also varied by degree of gene knock down. Studies were extended to address the functional impact of the MRE11a SNP on DRC by challenging lymphocytes wild type or heterozygote for this SNP to bleomycin. A 30-40% reduction in DRC was seen in heterozygotes compared to wild type. Studies are ongoing to address the effect of chronic carcinogen exposure of HBECs with knock down of MRE11a on transformation efficiency and induction of gene promoter hypermethylation. These studies support a important role for MRE11A in the response of the cell to double-strand break damage. Supported by NIH R01 ES015262.

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 3918. doi:10.1158/1538-7445.AM2011-3918
Abstract 4075: Chemoresistant colorectal cancer cells exhibit high glycolytic activity
Authors: Tozzi Federico , Zhou Yunfei , Chen Jinyu , Bose Debashish , Fan Fan , Xia Ling , Wang Jinrong , Brusher Heather , Widger William , Ellis Lee M. , Waihua Zhang
Published: July 2012

Background: Overcoming drug resistance in colorectal cancer (CRC) requires an understanding the mechanisms by which cancer cells adapt to the genotoxic stress. We established oxaliplatin resistant CRC cells derived from HCT116 and HT29 cell lines (HCT116 OxR and HT29 OxR) (Yang AD et al, Clin Ca Res, 2007). The mechanisms by which these resistant clones reprogram their energy metabolism to gain a survival advantage remain unknown. In this study, we hypothesized that chemoresistant CRC cells would exhibit altered cellular metabolism in order to survive following chronic genotoxic stress.

Methods: The expression level of the glycolytic enzymes Glut1, hexokinase II (HK2), LDHA and HIF1α were detected by Western Blotting. Glucose uptake and lactate production was calculated by measuring the concentration of glucose and lactate in the culture media. Intracellular ATP/ADP levels, oxygen consumption and mitochondria ATP production were quantified. An in vivo xenograft study was used to compare the growth rate and angiogenesis of parental and oxaliplatin-resistant cells.

Results: Compared with the parental cells, both HT29-OxR and HCT116-OxR cells exhibited a metabolic phenotype with increased glycolysis as reflected by increased glucose uptake and lactate production. Glycolytic enzymes were upregulated in resistant cells including Glut1, HK2 and LDHA. HIF1α expression and VEGF levels in the conditioned media were increased in the resistant cells. The mitochondria of OxR cells demonstrated defective complex I/II substrate ATP production despite increased cellular oxygen consumption. Importantly, the OxR cells maintain higher levels of intracellular ATP and ATP/ADP ratio indicating a metabolic switch to glycolysis. In a tumor xenograft model, HT29 OxR cells grew significantly slower than parental HT29 cells. Interestingly, when OxR cells were mixed with parental HT29 cells (50:50 and 90:10), tumor growth and microvessel counts were significantly increased.

Conclusion: Oxaliplatin-resistant cells demonstrated: 1) high aerobic glycolytic activity, 2) an increase in HIF1α and glycolytic enzymes, and 3) defective mitochondria function. This metabolic switch provides more ATP production and likely contributes to the chemoresistant phenotype. Altering energy metabolism may provide a novel strategy to overcome drug-resistance in CRC cells.

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 4075. doi:10.1158/1538-7445.AM2011-4075
Abstract 408: Expression of interferon-stimulated gene 15 is a novel prognostic predictor for patients with advanced stage high-grade serous ovarian adenocarcinoma
Authors: Tsai Ching-Chou , Zaid Tarrik M. , Co Chloe N. , Yeung, Tsz-Lun , Thompson Melissa S. , Carroll Amy , Yeung Zachary P. , Wong Kwong-Kwok , Mok Samuel C.
Published: July 2012

Objectives: Utilizing the transcriptome profiling approach to identify genes that are differentially expressed in normal ovaries, and serous borderline ovarian tumors of low-malignant potential (LMP), and low-grade ovarian serous carcinomas compared with high-grade ovarian serous carcinomas (HGSC), we identified ISG15, an ubiquitin-like molecule that is strongly up regulated by type I interferon, to be highly up-regulated in advanced stage HGSCs. We seek to validate the expression patterns of ISG15 and correlated them with clinical outcomes.

Methods: Over-expression of ISG15 was confirmed in ovarian cancer cell lines and tissue by real time PCR and immunohistochemistry, respectively. Immunolocalizaation of ISG15 was performed on 155 HGSCs, 10 serous LMPs, 10 normal ovaries, and 10 fallopian tubes. Expression levels of ISG15 were quantified by Image-Pro plus software. The correlation between overall survival and progression free survival and ISG15 expression levels was performed on 155 and 130 HGSC, respectively, using both Kaplan Meier and Cox Regression analyses.

Results: ISG15 expression was not detected in normal ovaries, fallopian tubes and LMPs. Over-expressed of ISG15 was confirmed in a majority of HGSC cell lines and tumor tissue. To further evaluate the clinical significance of nuclear ISG15 expression, both Cox and Kaplan-Meier analyses were performed on patients with HGSC. Multivariate Cox analysis showed that ISG15 expression levels were associated with improved overall survival (HR:0.9, P=0.011). In addition, using median ISF15 staining intensity as a cut-off, Kaplan-Meier analysis and log rank test demonstrated that strong ISG15 expression was associated with improved overall and progression free survival (P<0.001 and P=0.002, respectively).

Conclusion: Over-expression of ISG15 is common in high-grade serous ovarian adenocarcinoma. The expression levels in tumor cells are strongly correlated with overall survivals, suggesting ISG15 may be a powerful prognostic marker for patients with HGSC. Further functional studies on the functional role of ISG15 in ovarian cancer progression are warranted.

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 408. doi:10.1158/1538-7445.AM2011-408
Abstract 4082: Protection of acetaminophen-induced cytotoxicity by diallyl sulfide in mouse macrophages and HepG2 cells
Authors: Raza Haider , John Annie
Published: July 2012

The nonsteroidal anti-inflammatory drugs (NSAIDs), including acetaminophen (APAP), have been reported to induce cytotoxicity in cancer and non-cancerous cells. The precise molecular mechanisms, however, are not well understood. Our previous studies on HepG2 cells treated with aspirin and mouse macrophage J774.2 cells treated with APAP strongly suggest cell cycle arrest and induction of apoptosis associated with mitochondrial dysfunction and oxidative stress. Macrophages are known to play a critical role in toxicity as well as in protection of target tissues against the toxicity induced by NSAIDs. In the present study, we have demonstrated that macrophages are a more sensitive target for APAP -induced toxicity than HepG2 cells. Using similar dose- and time-point studies, a marked increase in apoptosis, DNA fragmentation, cytochrome c release and PARP/caspase 3 activation was seen in macrophages compared to HepG2 cells. Differential effects of APAP on mitochondrial respiratory functions and oxidative stress were observed in the two cell lines which are presumably dependent on the varying degree of reactive oxygen species (ROS) production and alterations in glutathione metabolism. In contrast to macrophages, our results also demonstrate a marked increase in glutathione transferase activity in APAP-treated HepG2 cells. This may explain the apparent resistance of HepG2 cells to APAP toxicity compared to the macrophages. Treatment of these cells with diallyl sulfide (DAS, 200 µmol/ml), a known chemopreventive agent from garlic extract, 24 h prior to APAP (10 µmol/ml for 18h) exposure have also exhibited comparable cytoprotective effects in the two cell lines. These results may help in better understanding the mechanism of cytotoxicity caused by APAP and cytoprotection by chemopreventive agents in cancer and non-cancerous cellular systems. (Supported by Terry Fox Cancer Research Funds and a fund from FMHS Research Committee).

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 4082. doi:10.1158/1538-7445.AM2011-4082