bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 765: Drug discovery for targeting the tumor microenvironment from propolis
Authors: Nagasawa Hideko K. , Hattori Hisanori , Narise Kosuke , Watarai Tatsuya , Ueda Satoshi , Okuda Kensuke
Published: February 2011

The tumor microenvironment, characterized by regions of hypoxia, low nutrition, and acidosis due to incomplete blood vessel networks, has been recognized as a major factor that influences not only the response to conventional anti-cancer therapies but also malignant progression and metastasis. However, exploiting such a cumbersome tumor microenvironment for cancer treatment could provide tumor-specific therapeutic approaches. In particular, hypoxia is now considered a fundamentally important characteristic of the tumor microenvironment in which HIF-1 mediated gene regulation being essential for angiogenesis and tumor development. This has led to the current extensive interest in the drug discovery for tumor microenvironment including tumor specific potential molecular targets for cancer therapeutics. Propolis has pleiotropic effects and contains a variety of bioactive polyphenolic compounds. Some flavonoids of them have been reported to inhibit HIF-1α. We therefore evaluated the effects of composition of Brazilian propolis on cellular responses to hypoxia or nutrition deprivation stress for the development of novel anti-cancer drug targeting the tumor microenvironment.

Materials and Method: The ethanol extract of Brazilian propolis was subjected to a series of chromatographic separations to examine HIF-1 inhibition and cytotoxicity under hypoxic and/or glucose deprived condition. The HIF-1α trans-activation effect was evaluated by HIF-1 reporter assay using stable cell lines expressing p2.1. The effect on unfolded protein response (UPR) activation in tumor cell induced by glucose deprivation or 2-deoxyglucose was also examined by GRP78 promoter reporter assay. We performed Immunoblot analysis of the HIF-1α and UPR target genes. The effects on HIF-1α dependent gene expression were investigated by RT-PCR using HCT116 cells.

Result: The propolis whole extract increased HRE-dependent luciferase activity in a dose-dependent manner. From a series of chromatographic separations, we obtained fractions 3, 5 and 8 that inhibited HIF-1-dependent induction of luciferase, while fractions 6 and 10-13 increased the luciferase activity. Cinnamic acid derivative, GPU-215 was isolated from Fr.6 reduced HIF1 transactivation activity, expression of HIF-1α protein and GLUT1 mRNA under hypoxia, while flavonoid, GPU-216 from Fr.8 increased HIF-1α transactivation activity and UPR activation.

Conclusion: We discovered promising compounds from Brazilian propolis for novel anti-cancer drug targeting tumor microenvironment. GPU-215 has inhibitory effect on HIF-1α expression and function, while GPU-216 increased HIF-1α transactivation and UPR activation.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 765.
Abstract 767: The effects of triptolide on human breast cancer cells
Authors: Halaby Reginald , Messina Michael
Published: February 2011

This research seeks to investigate how triptolide, an extract from the Chinese herb Tripterygium wilfordii Hook F, induces apoptosis in MCF-7 and SK-BR-3 human breast cancer cells. Triptolide is known to have anti-proliferative, anti-inflammatory, and anticancer properties. It has been used for over two centuries in Chinese medicine and is now used to treat certain autoimmune diseases. With breast cancer plaguing the United States as the second leading cause of cancer related deaths amongst women, as well as the adverse effects of current treatment methods to patients, there is a need for the development of safer and noninvasive treatments. Triptolide induces apoptosis in human breast cancer cells, but the exact mechanism is still largely unknown. In this study, we examined the ability of triptolide to regulate the protein expression levels of caspase-7 and caspase-9, PARP, and Bcl-2 via western analysis and the Pierce UnBlot In-Gel Chemiluminescent Detection Kit. Apoptosis was monitored using the MTT cell viability assay, LysoTracker™ staining, and measuring tumor volumes in nude mice bearing MCF-7 and SK-BR-3 xenograft tumors. Preliminary results indicate that the amount of apoptosis, which was significantly increased by triptolide in these cells, is both time- and dose-dependent, suggesting that there may be an optimal triptolide concentration for maximal anticancer efficacy. Triptolide differentially regulated the expression of pro- and anti-apoptotic proteins. Furthermore, triptolide decreased tumor volumes in vivo. Further investigation is warranted to determine if and how triptolide is activating the intrinsic apoptotic pathway.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 767.
Abstract 770: The orphan receptor Nur77 overexpression and translocation induced by PCH4 may inhibit malignant brain tumor growth and induce cell apoptosis
Authors: Li-Fu Chang , Lin Po-Cheng , Chiou Tzyy-Wen , Harn Horng-Jyh
Published: February 2011

N-butylidenephthalide(BP), a nature compound from Angelica sinensis, has the antitumor effect in vitro and in vivo. Further, we modified the chemical structure of BP for increasing the antitumor effect and one derivative is (Z)-N-(2-(dimethylamino)ethyl)-2-(3-((3-oxoisobenzofuran-1(3H)-ylidene)methyl)phenoxy)acetamide, PCH4, has 4 times tumor inhibition on human glioblastoma multiform DBTRG-05MG cells. The IC50 of PCH4 on DBTRG-05MG cells is 50 μg/ml. The PCH4 induced apoptosis was related to Nur77 expression and translocation from nucleus to cytosol. Furthermore, the inhibition of PCH4-induced Nur77 expression by Nur77 siRNA can reduce the PCH4-induced apoptosis. In addition, The PCH4-induced apoptosis was associated with JNK pathway. The JNK inhibitor, SP600125, inhibited the Nur77 mRNA expression and reduced the PCH4-induced apoptosis. In conclusion, It suggesting us that the PCH4, the derivatives of BP, induce the Nur77-mediated apoptosis through the JNK pathway and this mechanism different from BP may increase the antitumor effect on GBM cells.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 770.
Abstract 771: The antimetastasis mechanism of curcumin in colorectal cancer cells
Authors: LIN YU-SHUANG
Published: February 2011

Colon cancer has become a more serious threat to public health due to the changes of the dietary habits in many developed countries. In clinic, the proper therapeutic strategies for colon cancers are complete surgery resection for local diseases, and systematic chemotherapy and radiotherapy for metastatic diseases. However, tumor metastasis is the primary cause resulting in cancer death. Curcumin has been used as an important traditional medicine in almost any kind of illness including cancers. Over the past years, curcumin has been proved to be a multifunctional chemotherapeutic agent. However, the anti-tumor mechanism of curcumin is not completely understood yet. In this study, we investigate the underlying anti-metastasis mechanism of curcumin in colon cancer. Our results showed that curcumin inhibits cell proliferation (IC20 at 20 μM), cell migration (99% of inhibition at 20 μM), cell invasion (99% of inhibition at 20 μM), and colony formation (100% of inhibition at 20 μM) in a dose-dependent manner in colon cancer cells. Additionally, the differentially expressed genes of colon cancer cells treated with 20 μM curcumin were analyzed by Affymetrix genechip compared with mocks. There are 1,239 genes with greater than 2-fold change (p<0.05, FPR). The pathway analysis by using MetaCore and IPA software indicated that cell adhesion and cytoskeleton remodeling pathways may be involved in the anti-metastasis activity of curcumin. Several metastasis-related genes were found to be regulated by curcumin including integrin α2, integrin β5, paxillin and fibronectin. These findings suggest that curcumin may execute anti-metastasis activity by altering cell adhesion/cytoskeleton remodeling pathways in colon cancer cells.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 771.
Abstract 773: Identification and characterization of natural product-based inhibitors of hypoxia inducible factor-2 alpha
Authors: Rabe Daniel C. , McKee Tawnya , Woldemichael Girma M. , Vasselli James R. , McMahon James , Linehan W Marston , Bottaro Donald P.
Published: February 2011

Clear cell renal cell carcinoma (RCC) is the most prevalent form of kidney cancer and is frequently associated with loss of von Hippel Lindau (VHL) gene function, resulting in the aberrant transcriptional activation of hypoxia response genes that contribute to tumor growth, angiogenesis and metastasis. Prior studies have shown that normoxic stabilization of hypoxia inducible factor (HIF)-1-alpha alone, while capable of mimicking some aspects of VHL loss, are not sufficient to reproduce tumorigenesis, indicating that it is not the most critical oncogenic substrate of VHL protein. To isolate compounds that selectively modulate HIF2-alpha for use as research tools and drug development leads, a cell-based high throughput screen of the NCI Natural Products Repository was performed. Stably transformed clones of the human renal clear cell carcinoma cell line 786-0 expressing a luciferase reporter construct under the control of the human vascular endothelial growth factor (VEGF) promoter-enhancer were used to identify natural product samples with inhibitory activity and minimal cellular toxicity. Leads from initial high throughput screen were chromatographically separated into component structures yielding several pure compounds with micromolar or submicromolar IC50 values, >80% inhibition and <5% cell toxicity. These compounds were then characterized biologically for their ability to inhibit VEGF protein secretion by intact 786-0 cells; several compounds showed >90% inhibition of VEGF secretion at micromolar doses under normoxic conditions. Studies to establish HIF selectivity and effects on RCC cell proliferation, survival, motility and anchorage independent growth are underway.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 773.
Abstract 775: The antiproliferative effects of Mucuna macrocarpa stem extract on HL-60 leukemia cells
Authors: Chi Chin-Wen , Lu Kuan-Hung , Chang Yuh-Fang , Yi Pen-Hui , Chen Ting-Ting , Ho Yu-Ling , Chang Yuan-Shiun
Published: February 2011

Mucuna macrocarpa Wallich (Leguminosae) is believed to hold blood circulation activating effects, and has been used as a folk remedy in Southeast Asia for the treatment of various hematologic and circulatory related ailments. The objective of this study was to investigate whether crude methanolic extract of M. macrocarpa (CMEMM) possessed antileukemic effects on HL-60 human leukemia cells. CMEMM was prepared from dried stems of this plant, and phytochemical analyses of CMEMM revealed major components included lipids (tetracosanoic acid), sterols (mixture of β-sitosterol and stigmasterol), carbohydrates (sucrose and D-pinitol), triterpenoids (friedelin) and isoflavones (medicarpin, calycosin, afrormosin and genistein). The apoptosis-inducing effects of CMEMM were investigated using HL-60 cells in vitro and in vivo. With treatment of 25 to 75 µg/ml CMEMM, the in vitro antiproliferative effect on HL-60 cells increased in a dose- and time-dependent manner during the 72 h treatment period. The concentration of CMEMM that exhibited a 50% growth inhibition (IC50) for 72 h exposure was 36.4 μg/ml. Apoptosis triggered by CMEMM in HL-60 cells was confirmed by the following observations: (1) characteristic apoptotic nuclear fragmentation, (2) dose-dependent accumulation of sub-G1 phase in cell cycle analyses, (3) increased percentages of annexin V-positive apoptotic cells, and (4) dose-dependent elevation of active caspase-3. Additionally, the in vivo effect of CMEMM (500 mg/kg/day i.p.) on suppression of HL-60 tumor growth was observed in mouse xenografts. Moreover, CMEMM exerted anti-inflammatory activities by suppressing production of proinflammatory cytokines, TNF-α and IL-6, in lipopolysaccharide-activated RAW264.7 macrophages. These results together suggest that CMEMM exerted a novel antileukemic effects via an apoptotic pathway on HL-60 cells. Further characterization of the active components in CMEMM and their action in antitumor response will be important for future clinical application.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 775.
Abstract 778: Implication of MAP kinases in the induction of G1 arrest and gadd45 expression by fucoxanthin, a natural carotenoid
Authors: Nishino Hoyoku
Published: February 2011

We have recently demonstrated that fucoxanthin, a natural carotenoid, induces G1 cell cycle arrest in human cancer cells. Up to date, the action mechanism of fucoxanthin has not been elucidated yet. In the present study, we demonstrate that action mechanism of fucoxanthin is very complicated and different depending on the type of cancer cells. Never the less, the induction of gadd45 seems to be important, which is regulated by mitogen-activated protein kinases (MAPKs); p38 MAPK and ERK.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 778.
Abstract 780: Dimethyl cardamonin induces G1-phase cell cycle arrest, apoptosis, and autophagy in HCT116 cells
Authors: ko Hyeonseok , Kim Young-Joo , Park Jin-Soo , Amor Evangeline C , Lee Jong Wha , Yang Hyun Ok
Published: February 2011

Dimethyl cardamonin (2’,4’-dihydroxy-6’-methoxy-3’,5’-dimethylchalcone; DMC) is a naturally occurring chalcone, and it is the major compound isolated from the leaves and/or fruits of Syzygium samarangense (Blume) Merr. & L.M. Perry (Myrtaceae). DMC has been reported to have anti-diabetic, anti-bacterial, spasmolitic and anti-tumor properties. Furthermore, it has been used as an antipyretic and a diuretic agent in Taiwan folk medicine. However, the underlying mechanisms of its anti-tumor effects have not been studied. Here, we report that DMC induced G1 phase arrest, apoptosis and autophagy in HCT116 cell line. In this study, DMC decreased the expression of the phospho-Rb, CDK4 and cyclin D1 expression level, which is correlated with G1 phase. We also found that DMC-induced apoptosis occurred through the p53 dependent manner and the mitochondrial death pathway as evidenced by reduction of the Bcl2, XIAP and caspase-9 activation, and by induction of Bims. And, we showed that DMC up-regulates activity of JNK and p38. Interestingly, we found that DMC elicits autophagy, a process that participates in apoptotic response, in a JNK and p53-dependent manner, in HCT116 cell line. We also found that the increased activation of JNK by DMC is partially regulated by p53, highlighting the relationship of JNK and autophagy to p53 signaling pathway. The treatment of HCT116 (p53 -/-) cell line with DMC resulted in reduction in both apoptotic and autophagic effects relative to HCT116 (p53 +/+) cell line. This study suggested that DMC induced the multiple effects of G1 phase arrest, apoptosis and autophagy through JNK and p53 in HCT 116 cell line.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 780.
Abstract 790: Mutations and copy number gains of EGFR and KRAS genes in lung adenocarcinomas
Authors: Soh Junichi , Toyooka Shinichi , Yamamoto Hiromasa , Shigematsu Hisayuki , Asano Hiroaki , Yamane Masaomi , Tsukuda Kazuhiro , Oto Takahiro , Gazdar Adi F. , Miyoshi Shinichiro
Published: February 2011

Background: Activating mutations or copy number gains (CNGs) of epidermal growth factor receptor (EGFR) and KRAS genes are major oncogenic alterations in lung adenocarcinomas. While mutations of these genes are well-known to be mutually exclusive each other, the interrelationship of four genetic alterations (mutations or CNGs of EGFR or KRAS gene) has never been investigated.

Material and methods: We determined these four genetic alterations in 314 lung adenocarcinoma cases including 176 Asians and 138 Non-Asians from four countries with complete clinical information. Mutational and CNG statuses of EGFR or KRAS gene were determined by direct sequencing and quantitative PCR method, respectively.

Results: EGFR mutations (mEGFR), EGFR CNGs (gEGFR), KRAS mutations (mKRAS) and KRAS CNGs (gKRAS) were present in 25%, 35%, 23% and 6% of 314 cases, respectively (Table 1). Either alteration of EGFR or KRAS gene was present in 41% and 20% of all cases, respectively. Alterations of either EGFR or KRAS gene were observed in 67% of 314 cases, that was significantly more frequent in Asian never smokers (84%) than other groups (61%, P = 0.0001). Of note, CNGs of both genes preferentially occurred in their respective mutant case (P = 0.001 in EGFR and P = 0.04 in KRAS). mEGFR and mKRAS were completely mutually exclusive each other while gEGFR and gKRAS were not. Either alteration of EGFR was also exclusively present with either alteration of KRAS (P < 0.0001) while 19 cases (6%) had alterations of both genes. Interestingly, gKRAS was detected in one case among 79 mEGFR cases (1.3%) while gEGFR could be observed in 10 cases among 71 mKRAS cases (14.1%, P = 0.003).

Conclusion: Activations of EGFR and/or KRAS genes are present in about 70% of lung adenocarcinomas. Activations of EGFR or KRAS gene are almost exclusive and activating mutation of EGFR rarely accompanies KRAS activation, suggesting that two genetic alterations independently associate with oncogenesis of lung adenocarcinomas.Table 1.Activated pathway of 314 lung adenocarcinomasActivated pathwayTypes of activationn%Both genesSubtotal196.1 m, gEGFR + gKRAS10.3 gEGFR + m, gKRAS51.6 gEGFR + mKRAS51.6 gEGFR + gKRAS82.5    EGFR gene aloneSubtotal12941.1 mEGFR3912.4 m, gEGFR3912.4 gEGFR5116.2    KRAS gene aloneSubtotal6219.7 mKRAS5818.5 m, gKRAS31.0 gKRAS10.3    NoneSubtotal10433.1

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 790.
Abstract 792: Prognostic significance of four molecular markers in relation to fatal prostate cancer after prostatectomy
Authors: Weinmann Sheila , Haque Reina , Kallakury Bhaskar , Richert-Boe Kathryn , Berry Deborah , Van Den Eeden Stephen
Published: February 2011

Aside from Gleason grade, there are no established biomarkers to differentiate aggressive from indolent disease in early-stage prostate cancer. Such markers are needed to stratify patient selection for radical or conservative treatment. In the population of three managed care organizations, we conducted a case-control study to evaluate the predictive value of immunohistochemical expression of four molecular markers in formalin-fixed paraffin-embedded tumor tissue from prostatectomy specimens. Cases included 286 men whose prostate cancers progressed to death between 1971 and 2001; 344 controls with non-fatal prostate cancer were closely matched to cases on age, race, tumor stage, diagnosis year, and patterns of health plan membership. One expert prostate cancer pathologist reviewed all pathology slides to determine Gleason grade and select the highest grade tumor specimen for analysis. Formalin-fixed paraffin embedded tissue sections from the above specimens were immunostained by an automated method using antibodies against Ki-67, p53, p27kip1 and BCl-2. Immunoreactivity was semi-quantitatively scored based on intensity and percentage of positive cells in both tumor and adjacent benign tissue, and results were correlated with clinicopathologic variables. Using unconditional logistic regression analysis, we identified Ki-67, P53, P27kip1, and BCl-2 as statistically significant predictors of prostate cancer mortality after adjustment for age, group, race, health plan, diagnosis year, and tumor stage. Marker expression was classified as presence yes/no (P53, BCl-2) or absence yes/no (P27kip1) of any staining or 10%+ expression vs. less (Ki-67). After further adjustment for Gleason grade, marker associations with mortality were as follows: Ki-67 odds ratio = 12.3, 95% confidence interval (CI) 5.3-28.3, p<0.0001; P53 odds ratio = 1.6, 95% CI 1.1-2.3, p=0.02; P27kip1 odds ratio = 2.1, 95% CI 0.90-4.9, p=0.09; BCl-2 odds ratio = 1.3, 95% CI 0.77-2.1, p=0.35. When we combined the four markers into one multivariate model including the matching variables and Gleason grade, only the association with the Ki-67 marker reached statistical significance (odds ratio = 10.6, 95% CI 4.2-26.8, p<0.0001). We conclude that the proliferative index as assessed by Ki-67 immunoreactivity is an independent predictor of aggressive prostate cancer and may have an important role in the selection of the most appropriate therapeutic option in patients with this disease.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 792.
Abstract 798: Adenomas in Lynch syndrome: Diagnostically useful
Authors: Rosty Christophe , Walsh Michael , Buchanan Daniel , Arnold Sven , Clendenning Mark , Walters Rhiannon , Hopper John , Jenkins Mark , Jass Jeremy , Young Joanne
Published: February 2011

Background: Debate continues as to the usefulness of testing adenomas for loss of mismatch repair (MMR) proteins to identify individuals with suspected Lynch syndrome. Several studies have suggested that it is only worthwhile testing large, proximal adenomas exhibiting high grade dysplasia while others report disappointing “hit rates” even from known mutation carriers. Screening of unselected early-onset adenomas for MMR deficiency has yielded disappointing results.

Design: We tested 88 adenomas from 49 proven mutation carriers (23 female and 26 male) from 37 Lynch syndrome families (12 MLH1, 21 MSH2, 3 MSH6 and 1 PMS2) enrolled in the Australasian Colorectal Cancer Family Study which is part of the Colon Collaborative Family Registry (C-CFR). The average age of diagnosis of first polyp studied was 49.1 ± 9.6 years (ranging from 30.3 to 72.0 years).

All polyps were tested by immunohistochemistry (IHC) for the four MMR proteins MLH1, MSH2, MSH6 and PMS2. In addition, microsatellite instability testing using a panel of 10 markers (incorporating the standard NCI panel) was performed on 69 adenomas. All polyps were subjected to a standard review by one specialist pathologist (JJ). The majority of adenomas included in the present study were tubular adenomas (n = 61), with 22 tubulovillous adenomas, 1 villous adenoma, and 4 traditional serrated adenomas.

Results: Overall, abnormal immunohistochemical results (loss of expression) were noted for 73/88 (82.9%) of the adenomas from MMR gene mutation carriers. In all instances, loss of expression was consistent with the underlying germline mutation. MSI testing was concordant with immunohistochemistry in 66/69 (95.6%) cases. There was no statistical difference in patient ages at the time of polypectomy between MMR deficient and intact adenomas (49.6 ± 9.5 yrs vs. 49.8 ± 11.6 yrs). 15/88 (17.1%) polyps demonstrated normal MMR IHC. Six of these polyps came from four individuals who had other polyps which demonstrated abnormal IHC), whilst the remaining nine adenomas came from nine individuals for whom other adenomas had not been tested. Of these 9 cases, however, three had been diagnosed with Lynch syndrome-spectrum tumours which showed appropriate loss of MMR protein(s)

Conclusions: Diagnostic testing of adenomas from patients from Lynch syndrome families is a useful alternative in cases where cancers are unavailable. The overwhelming majority (82.9%) of adenomas from carriers show appropriate loss of MMR proteins and a high level of concordant microsatellite instability. We were unable to demonstrate an association between adenoma grade, size or site and MMR deficiency.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 798.
Abstract 8: Reptin is required for the transcription of telomerase reverse transcriptase and overexpressed in gastric cancer
Authors: Li Wenjuan , Jia Jihui , Zeng Jiping , Li Qiao , Björkholm Magnus , Xu Dawei
Published: February 2011

Telomerase is activated in oncogenesis, which confers an immortal phenotype to cancer cells. The AAA+ ATPases Reptin and Pontin have recently been identified to be required for telomerase biogenesis by maintaining telomerase RNA (hTER) stability. Given their roles in chromatin remodeling and transcription regulation, we determined the effect of Reptin and Pontin on the transcription of the telomerase reverse transcriptase (hTERT) gene, a key component of the telomerase complex. The depletion of Reptin or Pontin in gastric and cervical cancer cells led to significant decreases in hTERT mRNA, but hTERT promoter activity was inhibited in only Reptin-depleted cells. Reptin interacted with the c-MYC oncoprotein and its stimulatory effect on the hTERT promoter was significantly dependent on functional E-boxes in the promoter. Moreover, Reptin bound to the hTERT proximal promoter and the loss of the Reptin occupancy led to dissociation of c-MYC from the hTERT promoter in Reptin-depleted cancer cells. We further demonstrated that Reptin inhibition dramatically impaired clonogenic potential of gastric cancer cells and that Reptin was over-expressed in primary gastric cancer specimens. Collectively, the hTERT gene is a direct target of Reptin, and hTERT transcription requires constitutive expression of Reptin and its cooperation with c-MYC. Thus Reptin regulates telomerase at two different levels. This finding, together with the requirement of Reptin for clonogenic potentials of cancer cells and its widespread over-expression in primary gastric cancer, suggests that Reptin may be a putative cancer therapeutic target.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 8.
Abstract 80: Streptozotocin-induced cytotoxicity and mitochondrial dysfunction in human hepatoma HepG2 cells
Authors: Raza Haider , John Annie
Published: February 2011

Streptozotocin (STZ) is an antibiotic often used in the treatment of different types of cancers, including the liver cancer. STZ is also highly cytotoxic to the normal pancreatic beta-cells and therefore is being commonly used to develop experimental type 1 diabetes in rat and mouse models. Resistance towards STZ-induced cytotoxicity in cancer cells has also been reported. The precise molecular mechanism of STZ cytotoxicity/resistance in different tissues and carcinomas is, however unclear. STZ increases cellular oxidative stress by producing reactive oxygen (ROS) and nitrogen (RNS) species. We have investigated the mechanism of cytotoxicity of STZ in HepG2 cancer cells in culture. Cells were treated with different doses of STZ for different time intervals and the cytoxicity was studied by observing the alterations in oxidative stress, mitochondrial redox and respiratory functions. STZ induces ROS and RNS formation and oxidative stress as measured by an increase in the lipid peroxidation and nitrate production as well as alterations in the GSH metabolism. The mitochondria appear to be a more sensitive target for STZ toxicity than extramitochondrial compartments. The mitochondrial membrane potential was altered in STZ treated cells. Activities of the mitochondrial respiratory electron transporting enzymes; complex I and cytochrome c oxidase were also modulated resulting in the inhibition of ATP synthesis. The ROS-sensitive mitochondrial aconitase activity was also inhibited suggesting the involvement of oxidative stress in STZ-induced mitochondrial toxicity. The nuclear translocation of oxidative stress marker protein, NF-kB was increased in STZ treated cells. The expression of Hsp70, an oxidative stress marker protein, was also increased in the drug treated cells. The apparent absence of apoptotic markers such as cytochrome c release and the activation of caspase 3 in STZ treated HepG2 cells suggest that the intrinsic mitochondrial apoptosis pathway may not be primarily involved in STZ-induced cytotoxicity. The results suggest that STZ-induced cytotoxicity in HepG2 cells is mediated, at least in part, by the increase in ROS/RNS production, oxidative stress and mitochondrial dysfunction. This study may be significant in better understanding the mechanisms of STZ action in chemotherapy and drug resistance. The study is supported by Research Committee grant and a grant from Terry Fox Cancer Research funds.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 80.
Abstract 803: Expression of poly(adenosine diphosphate-ribose) polymerase (PARP) and p53 in epithelial ovarian cancer
Authors: Godoy Heidi E. , Mhawech-Fauceglia Paulette , Beck Amy , Miller Austin , Lele Shashikant , Odunsi Kunle
Published: February 2011

Objectives:

PARP, poly(adenosine diphosphate-ribose) polymerase, is a damage sensing protein that is essential to the repair of DNA single-strand breaks. P53 acts as a “genome guardian” molecule that in response to DNA damage mediates cell cycle arrest or induces apoptosis. PARP and p53 function synergistically in repairing DNA damage and suppressing chromosomal rearrangements. The aim of this study was to determine the expression of PARP and p53 in epithelial ovarian cancer (EOC) and correlate with clinico-pathologic characteristics.

Methods:

PARP and p53 was examined using immuno-histochemistry applied on a tissue microarray of 189 EOC. PARP and p53 expression were examined in relation to clinco-pathologic variables, including age of diagnosis, stage, grade, histologic type, optimal debulking, progression free survival and overall survival. Progression free survival and overall survival were estimated by Kaplan-Meier method, and statistical significance was calculated by the log-rank test.

Results:

PARP expression was demonstrated in 61% (115/189) of specimens and 99/185 (54%) samples exhibited p53 staining. PARP positive tumors tended to have higher grade (P = 0.03) and complete response to initial treatment (P = 0.009). Patients with positive p53 staining tended to have higher stage of disease (P = 0.004) and there was a trend of patients with positive p53 and weak PARP expression to increase the likelihood of disease progression (OR 2.25 (CI 0.389-13)). The median follow-up was 40 months. However, there were no significant associations between PARP and p53 expression. There was no significant difference in disease free or overall survival for PARP or p53.

Conclusion:

This study indicates that PARP and p53 are upregulated in EOC with higher grade tumors and more advanced stages, respectively, and may serve as a marker of aggressive disease behavior. Additional studies are warranted to evaluate the role of PARP and p53 expression as a predictor of response to initial treatment, and to identify patients that may benefit from alternative treatments in the adjuvant setting.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 803.
Abstract 806: Upregulation of Krüppel-like Factor 4 (KLF-4) expression as a potential tumor progression gene product in non-Hodgkin's lymphoma
Authors: Vega Mario I. , Hernandez-Atenógenes Miriam , Vazquez-Islas Juan C. , Martinez-Miguel Bernardo , Martinez-Paniagua Melisa A. , Antonio-Andres Gabriela , Rivera-Pazos Clara M. , Maldonado-Valenzuela Altagracia , Martinez-Maza Otoniel , Huerta-Yepez Sara , Bonavida Benjamin
Published: February 2011

Krüppel-like factor 4 (KLF-4) is highly expressed in epithelial tissues such as gut and skin. Several studies based on clinical evidence suggest that KLF-4 functions as a tumor suppressor in cancer of colon, bladder, stomach and in leukemia. In contrast, KLF-4 expression is increased in primary breast ductal carcinomas and in oral dermal squamous cell carcinomas, suggesting that KLF-4 is important in tumor development and progression. However, KLF-4 expression in lymphomas has not been investigated. Our preliminary studies have examined KLF-4 expression in lymphoma cell lines and a TMA containing fresh tissues derived from patients with several types of lymphoma. There was a significant higher expression of KLF-4 in Burkitt's lymphoma compared with other lymphomas such as follicular or DLBCL. These findings suggest that KLF-4 may be considered as a new biomarker in Non-Hodgkin's lymphoma (NHL). Further analyses based on the clinical outcome revealed that KLF-4 protein expression was significantly associated with poor patient's survival. The increased KLF-4 expression was associated with an inferior survival duration (P= 0.002). The survival for 12 patients who had a tumor with weak KLF-4 expression and 13 patients with negative KLF-4 expression was significantly longer than the 30 patients with strong KLF-4 expression (P< 0.001). Other variables that affected survival in univariate analyses included stages and completeness of resection were shown to have statistically significant effect on survival (P=0.001), however age or sex did not have a statistically significant effect on survival. These data provide the first clinical and causal evidences that alterations of KLF-4 expression can play a critical role in the development and progression of NHL.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 806.
Abstract 813: Prognostic impact of the expression of cancer stem cell markers CD166, CD44, EpCAM, ALDH1 and CD133 in colorectal cancer
Authors: Iezzi Giandomenica , Lugli Alessandro , Muraro Manuele G. , Mele Valentina , Hostettler Isabel , Tornillo Luigi , Carafa Vincenza , Spagnoli Giulio C. , Terracciano Luigi , Zlobec Inti
Published: February 2011

Background: The aim of this study was to elucidate the prognostic impact of the putative cancer stem cell (CSC) markers CD166, CD44s, EpCAM, ALDH1 and CD133 by immunohistochemistry in colorectal cancer and determine their value as potential biomarkers of clinical outcome.

Methods: Using the tissue microarray technique, immunohistochemistry was performed on samples from 1420 primary colorectal cancer patients with full clinico-pathological data and 57 normal tissues. Expression was evaluated semi-quantitatively and receiver operating characteristics (ROC) curve analysis was used to identify reliable cut-off scores for positivity. Prognostic effects were subsequently validated using 101 randomly selected whole tissue sections. Invasive potential was tested using 3 colorectal cancer cell lines. Surgically excised colorectal cancer specimens were enzymatically digested and expression of CD166, CD44s and CD133 on tunour cells was evaluated by flow-cytometry. Cells were then injected in limiting amounts s.c. in NOD/SCID mice and allograft outgrowth was monitored by standard methods.

Results: A significant increase in CD166, CD44s and CD133 expression and a decreased expression of EpCAM and ALDH1 was noted in tumour compared to normal mucosa (p<0.001, all markers). Loss of membranous CD166, CD44s and EpCAM expression was associated with features of tumour progression, in particular with an infiltrating tumour border configuration (CD166: p<0.001; CD44s: p=0.002; EpCAM:p=0.005). Loss of CD166 and CD44s had a significant negative impact on survival time (p<0.001), which was further confirmed by evaluating corresponding whole tissue sections (p=0.006). CD44-/CD166- cells from 3 colorectal cancer cell lines exhibited in vitro significantly higher invasive potential than their positive counterparts. On the other hand, the ability of cancer cells to initiate tumours in immunodeficient mice was significantly (p=0.03) correlated with their content in CD133+, but not in CD166+/CD44+ cells.

Conclusions: Our findings indicate that loss of expression of CD166 and CD44s is linked to an aggressive tumour phenotype and, particularly, to the presence of an infiltrating tumour margin, possibly implicating these proteins in events at the invasive tumour front. Remarkably, the number of CD133+ cells, while important for tumour initiation in immunodeficient hosts, appears to be prognostically irrelevant in possibly immunocompetent patients.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 813.
Abstract 814: A systemic miRNA signature predictive of early breast cancer
Authors: Heneghan Helen M. , Miller Nicola , Kelly Ronan , Nugent Mary , Kerin Michael J.
Published: February 2011

Background:

The potential of miRNAs as novel tumor markers has been the focus of much recent attention due to their tissue specificity and unique ability to predict clinicopathological parameters with superior accuracy to mRNA expression profiling. Recent reports have documented altered serum or plasma miRNAs in a variety of cancers including prostate, colon, lung and breast. However it is unknown whether the specific miRNAs reported to be altered in these studies are tumor specific or a general cancer phenomenon. We wished to determine whether a panel of 9 circulating ‘oncomirs’ were tumor specific or similarly expressed in all cancers, and thus identify systemic miRNA signatures predictive of specific cancers.

Methods:

Using a real-time quantitative PCR approach, expression levels of a panel of 9 oncogenic miRNAs were quantified in blood specimens from 163 cancer patients (breast, colon, renal, prostate and melanoma) and 44 age-matched disease free control individuals. Advanced QBase Plus software and SPSS were used for biostatistical analysis of the data, and correlation with clinicopathological variables.

Results:

Our panel of circulating miRNAs were detectable at various levels in the circulation of all cancer patients. Expression of general oncomirs such as let 7a and miR-21 were similarly expressed in all cancers. However other specific miRNAs were remarkably different between cancer types. MiR-10b and miR-145 were significantly decreased in the circulation of colon cancer patients compared to other cancers (p=0.000 and p=0.017 respectively). MiR-195, miR-342 and miR-181c were found to be breast cancer specific; elevated levels of these three miRNAs could reliably differentiate breast cancer patients from healthy controls and from patients with other malignancies with high sensitivities (area under curve by ROC analysis: 0.941, 0.963, and 0.926 respectively). Furthermore, systemic miR-195 was detectable in patients with in-situ disease, levels increased progressively as stage of disease advanced, and decreased significantly post curative tumor resection to levels comparable with controls (p=0.001).

Conclusion:

These findings suggest that individual malignancies, in particular breast cancers, display specific systemic miRNAs profiles, which could aid in early diagnosis and in discriminating one cancer from another. This is of major clinical importance as it illustrates the potential for systemic miRNAs as sensitive and specific yet non-invasive cancer biomarkers.

Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 814.
Abstract 823: Identification of FISH biomarkers to detect chromosome abnormalities associated with prostate adenocarcinoma in tumor and field effect environment
Authors: Zhang Ying , Perez Thomas , Blondin Beth , Escarzaga Diana , Coon John , Morrison Larry , Pestova Katerina
Published: February 2011

Introduction. The focal nature of prostate cancer (CA) contributes to needle biopsy sampling error with false negative rates of 15-30%. Here we used fluorescence in situ hybridization (FISH) analysis to assess molecular abnormalities in prostate specimens as an aid to CA diagnosis. We also evaluated the feasibility of combined immunofluorescence and FISH to facilitate assessment of chromosomal abnormalities.

Experimental Procedure. 33 radical prostatectomy (RP) specimens from patients with adenocarcinoma of the prostate were evaluated by FISH with MYC, LPL, PTEN and centromere 8 probes. For each specimen, a tissue section was scribed by a pathologist to mark the tumor region(s). For 17 of the RP cases, a second section was available with only histologically benign tissue. FISH signals were enumerated in 50-100 cells per section. 26 hyperplasia (BPH) specimens, served as controls. Immunofluorescence (IF) with AMACR antibody was also used in the same assay with FISH.

Results. Chromosomal copy number abnormalities were observed in most RP specimens, both within tumor regions and extending beyond histologically evident tumor, while few abnormalities were observed in the BPH specimens, using a cut-off value for FISH positivity based on the mean +/- 2 SD of cells with less than or greater than 2 signals in BPH specimens. A combination of MYC gain, LPL loss, PTEN loss or chromosome 8 aneusomy within the scribed tumor regions identified adenocarcinoma in 82% (27/33) of RP specimens, with a specificity of 81% relative to BPH (χ2 p<0.001). When detected in regions of normal histology, these abnormalities correlated with adenocarcinoma in 47% (8/17 RP specimens, χ2 p=0.05 relative to BPH). IF combined with FISH facilitated selection of the abnormal regions of interest for molecular assessment in the heterogeneous prostate specimens. The IF-staining closely correlated with morphological assessment of tumor by a trained pathologist.

Conclusions. This study identified FISH probes for detection of chromosomal abnormalities associated with prostate CA that could potentially serve as a diagnostic aid in biopsy specimens. This study also indicates that chromosome abnormalities are present in RP specimens within regions of normal histology, indicating a substantial tumor field effect. Therefore, a molecular test based on FISH to measure abnormal MYC, LPL, PTEN and centromere 8 copy numbers may allow detection of cancer otherwise missed by histopathological examination and thus improve diagnosis of prostate cancer by reducing sampling error of needle biopsies.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 823.
Abstract 824: Comparison of the high risk HPV detection methods (HC II, DNA Chip, and luminex-based assay) in cervical lesion of Korean women
Authors: Shin Jae Eun , Kim Yun Sun , Kim Ku Hee , Bae Sumi , Kim Yong Wook , Park Dong Chun , Ahn Woong Shick
Published: February 2011

The detection of human papillomavirus (HPV) of female genital tract is very important, several HPV DNA detection methods have been developed during the last decade. In previous report, we introduced luminex-based HPV genotyping assay that is combined PCR amplification. In this study, we compared performances to detect high risk HPV types in hybrid capture 2 (HC II), DNA Chip, and luminex-based assay.

A total of 330 cervical swabs from Cervical Cancer Early Diagnostic Clinic, Seoul St. Mary's Hospital were investigated. DNA was extracted from a single sample and HPV DNA detection assays were performed on the same specimen with 3 strategies and confirmed by DNA sequencing. Among 330 cervical swabs, 230 were HPV positive, 100 were negative.

HPV detection rates of Luminex, HC II and DNA Chip in 330 specimens were 65.2%, 61.2% and 68.8%, respectively. The results of DNA sequence analysis, accuracy of Luminex, HC II and DNA Chip was 91.2%, 82.7% and 80.9%, respectively. HPV DNA infection slightly increase with severity of disease in cytologic and histologic diagnosis, there is no correlation between HPV, because HPV DNAs were detected in many samples with normal in this study.

Conclusively in HPV detection comparison, DNA Chip had relatively high detection rate than Luminex and HC II, but Luminex had the highest accuracy for HPV DNA detection. These results indicate that the Luminex-based assay has more accurate performance than DNA Chip and HC II assay in the detection of HPV infections. We suggest that Luminex-based assay may be useful method for detecting of HPV infection clinically.

Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 824.