bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 469: Functional imaging of the hypoxic tumor microenvironment in metastatic progression
Authors: Iglesias Pablo , Fraga Maximo , Costoya Jose A.
Published: February 2011

In the last years, the need for visualization of tumoral processes has become a high-top priority in molecular imaging. This is especially true for those methods dedicated to functional imaging that focus on revealing phenomena associated with biological processes such as hypoxia to cancer. Among them, optical imaging methods such as fluorescence are provided with a broad range of proteins and dyes used to visualize many types of these biological processes widely used in cell biology studies. Although the best-known example of these fluorochromes is the green fluorescent protein (GFP), tissue autofluorescence and signal dispersion raise doubts about its suitability as an in vivo tracer. However, a number of groups have recently developed several NIR fluorescent proteins that enable real-time imaging free of autofluorescence interference thus making possible to take a deep view into the tissues. With all of this in mind, we devised a novel fluorescence-bioluminescence genetically encoded biosensor activated by the neoangiogenesis-related transcription factor HIF-1α, which appears upregulated in growing tumors. At the same time, by fusing a fluorescent to a bioluminescent protein we obtained a bioluminescence resonance energy transfer (BRET) phenomenon turning this fusion protein into a new class of hypoxia-sensing genetically encoded biosensor. We also tested the inducibility and performance of this hypoxia sensor by imaging artificially activated cells both in culture (in vitro) and inside an animal model (in vivo). Finally, the breast cancer cell line MDA-MB 231, which is known by its invasiveness and ability to metastasize, was modified to carry the hypoxia sensor and subsequently injected intravenously in live mice. Metastases were detected in lung and brain by fluorescence and/or bioluminescence. In conclusion, we have described the designing and development of a functional dual hypoxia-sensing system able to display BRET activity between the firefly luciferase and the NIR fluorochrome. In addition a metastatic tumoral cell line was genetically modified to demonstrate that the biosensor is able to detect hypoxic conditions in metastasis in vivo, yielding valuable functional information about the tumor besides size and spatial localization.

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 469.
Abstract 4693: Maternal GSTP1 Ile105Val polymorphism and petrochemical exposure in relation to the childhood leukemia in southern Taiwan
Authors: Liu Chen-yu
Published: February 2011

We conducted a population-based case-control study in an industrial city of southern Taiwan to investigate childhood leukemia risk in relation to the association of maternal and offspring polymorphisms with residential petrochemical exposures. A total of 109 leukemia cases and 220 controls younger than 20 years were recruited between November 1997 and December 2005. A procedure using geographic information system tools was used to estimate individual-level exposure by accounting for subjects’ mobility, length of stay at each residence, distance to petrochemical plant(s), and monthly prevailing wind direction. Multivariate logistic regression was used to assess the effects of petrochemical exposures, maternal and offspring's GSTP1 genotypes, and their joint roles on offspring's leukemia risk. No main effect of residential petrochemical exposure was observed, yet the exposure association was influenced by maternal GSTP1 genotypes alone as well as by the combined maternal and offspring genotypes (P for interaction=0.02 and 0.01, respectively). Among the subjects with both mothers and offspring carrying the GSTP1 105Val variant allele(s), the adjusted odds ratio was 1.34 (95 percent confidence interval: 1.02, 1.76) for each unit of increase in the log-transformed exposure opportunity score. In conclusion, this study suggests that the childhood leukemia risk is associated with the residential petrochemical exposures, modified by both offspring's and maternal GSTP1 genotypes.

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 4693.
Abstract 4716: Mitochondrial DNA variants in colorectal adenomatous polyps
Authors: Aikhionbare Felix O. , Akwe Joyce A. , Mehrabi Sharifeh , Tah Sahil C. , Okoli Joel
Published: February 2011

Colorectal tumors mostly arise from sporadic adenomas (polyps). Polyps are defined as a mass of cells that protrudes into the lumen of the colon. Adenomatous polyps are benign neoplasms that, by definition display some characteristics of dysplasia and it has been well documented that polyps were benign tumors that may undergo malignant transformation. Adenomatous polyps have been classified into three histologic types, with increasing malignant potential; tubular, tubulovillous, and villous. The ability to differentially diagnose these colorectal adenomatous polyps is important for therapeutic intervention. To date, most efforts to identify genetic changes involved in adenomatous polyps have been focused on the nuclear genome. This study was designed to examine the relevance of mitochondrial genome alterations in the three adenomatous polyps. Using high resolution restriction endonucleases and PCR-based sequencing, fifty-seven primary fresh frozen tissues of adenomatous polyps (12 tubular and 5 matched surrounding normal tissues; 11 tubulovillous and 6 matched surrounding normal tissues and 14 villous and 9 matched surrounding normal tissues) obtained from the southern regional Cooperative Human Tissue Network (CHTN) and Grady Memorial Hospital at Atlanta were screened with three mtDNA regional primer pairs. Results from our data analyses revealed the presence of forty-seven variants in these mitochondrial genes; COX I, II, ATPase 6, 8, CYT b and ND 5. Six of the 49 variants detected were previously unreported and the MITODAT database [#J01415] was used as a sequence reference. Notably, a somatic variant C8515G/T in the MT-ATP 8 gene was observed at a frequency of 100% (12/12) in tubular adenomas and a germline variant 8327delA in the ATP 8 gene was observed at a frequency of 100% (47/47) among the tissue samples of the three adenomatous polyps. A germline variant G9055A in the MT-ATP 6 gene had a frequency of 100% (34/34) in tubular and villous adenomas; no corresponding variant was in tubulovillous adenomas. Furthermore, variant A9006G at MT-ATP 6 gene was observed at 74% (6/23) frequency of villous adenomas only. Interestingly, the A9006G variant was absent in six of the villous tissue samples that were clinicopathological designated as “polyvillous adenomas”. Our current data provide a basis for continued investigation of certain mtDNA variants as predictors of the three adenomatous polyps in a larger number of clinicopathological tissue specimens.

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 4716.
Abstract 4757: CancerVaccine: Novel proteinase treatment of melanoma cancer cells produces a cancer vaccine with enhanced protective adaptive immune response
Authors: Drewe John A. , Qian Yong , Shi Jin , McClurg Michael , Li Weidong , Campbell Tom
Published: February 2011

To facilitate the development of whole cell cancer vaccines, harmless derivatives or variants of cancer cells, BioMedicure reports here the development of a specific proteinase treatment to produce a whole cell melanoma cancer vaccine that induced specific adaptive or acquired immune responses against cancer cells specifically. The melanoma CancerVaccine was derived by treatment in vitro of B16 melanoma cells with a proteinase formulation, TumoraseTM (T101, BioMedicure, San Diego, CA). Studies show that the resultant preparation is nonviable in vitro and that upon injection into wild type or nude mice does not initiate tumors. In contrast, the same B16 cancer cells treated with other proteinases, as an example trypsin, readily replicate in vitro and elicit tumors in vivo. Wild-type mice vaccinated subcutaneously at day 1 and 15 were protected against subsequent challenge by living B16 cancer cells, with most attaining a normal lifespan. In contrast, animals that were not vaccinated or those vaccinated with TumoraseTM -treated normal cells grew large tumors and had to be sacrificed within 30 days due to large tumor burden. Major breakthroughs for the melanoma CancerVaccine are enhanced recognition by the immune system as foreign as shown by the almost complete protection. Proposed is that the TumoraseTM -treated non viable cancer cells are now recognized as foreign enhancing the antigen presentation process thus promoting engulfment by macrophage and dendritic cells for the antigen presentation process. Preserved are most, if not all, intracellular antigens that are general to heterogeneous cancer cells as well as specific to the cancer type all at their natural copy number. As more antigen species proceed through the antigen presentation process, the immune system sorts out the highly antigenic epitopes. The procedure does not introduce new antigens that may confuse the immune system since there is no molecular manipulation of the cells. Simple production with potential improved and consistent quality can be achieved during the manufacturing of this vaccine. With the TumoraseTM -treated B16 melanoma cells CancerVaccine antigens are presented on surfaces of professional antigen presenters without interference of self-recognition molecular patterns giving a good immune response and robust protection from tumor challenge. All of these advantages lead to more potent immune responses covering a wide range of cancer cell mutations. Therefore, CancerVaccine is expected to be an improvement over other whole cell cancer vaccines including gamma-ray irradiated whole cell cancer vaccines.

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 4757.
Abstract 476: Mammary tumors in lipocalin-2 deficient MMTV-PyVT mice grow faster but show decreased metastasis to lung
Authors: Chow Heiman , Fan Pengcheng , Xu Aimin , Hsiao Wen Laun Wendy , Wang Yu
Published: February 2011

Lipocalin-2, an iron and lipid binding glycoprotein, has been previously found to be abnormally expressed in malignant human cancers. In the present study, MMTV-polyomavirus middle T antigen (MMTV-PyVT) transgenic mice, with reduced or depleted lipocalin-2 expressions were established, for evaluating the stromal effects of lipocalin-2 deficiency on mammary tumor development. When compared to MMTV-PyVT control mice, lacking of lipocalin-2 delayed tumor onset but promoted the rate of tumor progression. However, lipocalin-2 deficiency led to a significantly reduced tumor metastasis to lungs. Mechanistic studies revealed that there was a reduced level of 12-Hydroxyeicosatetrenoate (12-HETE), a lipoxygenase metabolite positively related to tumor cell metastatic potential, in the tumor lysates of lipocalin-2 deficient mice. Replacement with lipocalin-2 by adenovirus based overexpression approach enhances mammary tumor metastasis through selectively upregulating the arachidonic acid metabolic pathway. Our findings, on the one hand support previous findings that lipocalin-2 is a pro-oncogenic factor in breast tumor development; on the other hand, the results also suggest that apart from its effect on matrix metalloproteinase activity, lipocalin-2 exacerbates tumorigenesis and metastasis through disrupting the lipid homeostasis in the tumor microenvironment.

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 476.
Abstract 4770: Cell-to-cell transfer of Ras proteins from cancer cells to lymphocytes at the immunological synapse is augmented upon antigenic specificity
Authors: Vernitsky Helly , Rechavi Oded , Nagar Meital , Kloog Yoel , Goldstein Itamar
Published: February 2011

Immune cells establish dynamic adhesive cell-cell interactions at a specific contact region, termed the immunological synapse (IS). Important features of the IS are the formation of cell-cell membrane fusions and bridges and the intercellular transfer of selected proteins. In previous studied we found that upon IS formation, a variety of Ras super-family members transfer intact from B cells to T and NK cells, and consequently transmit signals across cell boundaries. Mutations in Ras proto-oncogenes are rather common in human cancers, including melanoma, and moreover immunosurveillance is particularly important for the elimination of malignant melanoma. Thus, it was of interest to study whether mutated constitutively active Ras proteins transfer from HLA-2+ melanoma cells (MEL526) to patients-derived tumor infiltrating lymphocytes (TILs), and whether they can serve as a stimulatory ‘danger’ signal. Using an ex vivo co-culture system we found that TILs_as opposed to polyclonal T cells_efficiently and rapidly acquired intact H-Ras-G12V-GFP from MEL526 transfectants. Importantly, the adopted Ras was incorporated into the plasma membrane of the TILs in the correct in-out orientation. To study the functional consequences of the ‘non-autonomously translated’ H-Ras-G12V in the adopting TILs, we analyzed its effect on ERK1/2 activation and a variety of T cell effector functions. We found that the adopted H-Ras-G12V increased p-ERK1/2 levels in the adopting lymphocyte. Moreover, H-Ras-G12V-GFP+ TILs specifically produced more IFN-g and showed increased cytotoxic activity. In conclusion, our findings show a hitherto unobserved mode of intercellular signal transfer between T cells and cancer cells that may play an important role in the complex process of cancer immunoediting.

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 4770.
Abstract 4772: Hyperphosphorylated Paratarg-7, the first autosomal-dominantly inherited risk factor for hematological neoplasias: hyperphosphorylation by PKCzeta
Authors: Preuss Klaus-Dieter , Fadle Natalie , Regitz Evi , Grass Sandra , Klotz Markus , Pfreundschuh Michael
Published: February 2011

Antigenic targets of monoclonal gammopathy of undetermined significance (MGUS) and multiple myeloma (MM) paraproteins might play a role in the pathogenesis of these neoplasms. By screening a commercially available recombinant human cDNA expression macroarray we identified paratarg-7 as the antigenic target of the paraprotein from 14% (35/252) of all patients analyzed (Preuss et al. Int J Cancer 2009). The high frequency of hyperphosphorylated paratarg-7 as the antigenic target of paraproteins from MM/MGUS patients suggests that the modified protein is involved in the development of sporadic and familial MGUS/MM by acting as a chronic antigenic stimulus for the respective B-cell clones. With a relative risk of 7.9, the carrier state of hyperphosphorylated paratarg-7 (pP-7) is the strongest risk factor for the development of MGUS/MM. Moreover, the analysis of consanguineous relatives of MM/MGUS patients with an anti-paratarg-7 specific paraprotein showed that pP7 is inherited in a dominant fashion (Grass et al., Lancet Oncology, 2009). Here we present data showing that the hyperphosphorylation of paratarg-7 is due to an additional phosphorylation of this protein at the identical phosphorylation site when compared to normal paratarg-7. We identified protein kinase C zeta as responsible for this hyperphosphorylation which specifically occurs on Ser17 which is part of the 15 amino acid region identified as the paraprotein-binding epitope in all paratarg-7-immunopositive patients. In additional experiments no DNA modification of PKCzeta was detected. As shown by Western blot experiments and quantitative PCR no overexpression or copy number variation of PKCzeta was shown, suggesting that other not yet identified enzyme(s) must be involved in the process of paratarg-7 hyperphosphorylation or the maintenance of the hyperphosphorylated state.

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 4772.
Abstract 4779: Circulating and tumor-infiltrating CD4+IL-17+ T-cells in mice bearing orthotopic and heterotopic prostate tumors
Authors: Hung Tzong-Tyng , Russell Pamela J. , Power Carl A.
Published: February 2011

Helper T-cells expressing interleukin-17 are classified as TH17 cells, which are important in autoimmune disease and inflammatory responses. However, there are limited studies on their role and effects on cancer development and progression. Here we used a syngeneic murine model for prostate cancer, RM1(BM)-B4H7-Luc, to evaluate the proportion of TH17 cells in various organs (spleen, lymph nodes, prostate) and peripheral blood of tumour-bearing mice compared to normal mice. The number of tumour-infiltrating TH17 cells in tumours located at different sites (subcutaneous and prostate) were also compared. The proportion of TH17 cells in the peripheral blood of prostate tumour-bearing mice was significantly higher than in age-matched control mice (p<0.05) or mice bearing subcutaneous tumours (p<0.05). Additionally, an increase in the proportion of tumour-infiltrating CD4+ T cells expressing IL-17 was observed in both subcutaneous (9.28%) and prostate tumours (10.2%) compared to lymphoid organs (spleen and lymph node, <1%) from these mice, suggesting sequestration of these cells within the tumour. In addition, significantly higher numbers of TH17 cells were detected in prostate tumours compared to normal prostates (p=0.0357). Finally, the percentage TH17 in the peripheral blood of mice with prostate tumours correlated with the size of the tumour ((R2=0.84, p=0.0014). In conclusion, in our model, we show that TH17 cells are a significant proportion of tumour infiltrating T-cells and, as proposed in recent studies, they are likely to be involved in the anti-tumour immunity/tumour rejection. Importantly, the number of circulating TH17 cells correlates with tumour size for prostatic tumours, but not subcutaneous tumours. Thus, assessment of peripheral blood TH17 cells may be an effective tool for diagnosis/prognosis of prostate cancer. This relationship does not hold if subcutaneous models are used for preclinical studies.

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 4779.
Abstract 4780: CD4 T-lymphocyte responses to the human telomerase reverse transcriptase (hTERT) in patients (pts) with advanced non small cell lung cancer (NSCLC)
Authors: Fabre Elizabeth , CAZES Aurelie , Ravel Patrice , Medioni Jacques , Dosset Magali , Leviennois Emeline , Tartour Eric , Meyer Guy , Riquet Marc , Adotevi Olivier
Published: February 2011

Background: hTERT is a potential target for cancer immunotherapy because it is highly expressed in tumor cells. To assess the applicability of hTERT-based immunotherapy in NSCLC, we aimed to analyse the natural anti-hTERT CD4 T-lymphocyte responses in advanced NSCLC pts. Methods: We included in a prospective, monocentric study chemonaive NSCLC pts. Pts were required to present stage III or IV tumor, without any immune deficiency or immunosuppressive drug. Before start of chemotherapy, the anti-hTERT T-lymphocyte responses were assessed in whole blood by ELISPOT test. We evaluated the presence or absence of hTERT-specific CD4 T lymphocytes. Thereafter, we analyzed its link with age (< 70 vs. ≥ 70 yrs), ECOG performance status PS (0-1 vs. 2-3), tumoral stage (IIIA vs. IIIb + IV), histological subtype (adenocarcinoma vs. other) and smoking status (never smoker vs. smoker). Statistical analysis was performed using chi-Square or Fischer test. Results: Between February 2008 and October 2009, fifty-one NSCLC pts were included. They presented a stage IIIa (n = 5), IIIb (n = 5) or IV (n = 41) disease. Median age was 66 yrs [39-89]. Nineteen pts presented anti-telomerase CD4 T lymphocytes (37 %); among them we found 14 stage IV (73 %), 13 pts < 70 yrs (68 %), 12 pts with PS 0/1 (63 %), 18 adenocarcinoma/undifferentiated carcinoma (94 %), 13 pts with stable disease/ partial response (68%). Furthermore, all non smokers have anti-telomerase immune response. Conclusions: These preliminary results demonstrate that natural anti-hTERT immune response exists in NSCLC pts, even in case of advanced disease. However the presence of immune response is more frequently found in pts less than 70 yrs with good PS, in non squamous cell carcinoma and in pts with non progressive disease. The study is ongoing to evaluate if baseline anti-hTERT immune response could be used as selection criteria for telomerase vaccination in NSCLC.

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 4780.
Abstract 4787: GILT regulates antigen processing and CD4+ T cell recognition of melanoma cells
Authors: Haque Azizul , Norton Duncan , Doonan Bently , Amria Shereen
Published: February 2011

Metastatic melanoma is one of the deadliest of skin cancers and is increasing in incidence. Since current treatment regimens are ineffective at curing the disease, novel approaches, such as immunotherapy, for treating this malignant disease are being explored to elicit long-lasting antitumor immunity. We have previously shown that the majority of metastatic melanoma cells express HLA class II molecules, but lack Gamma-Interferon-inducible Lysosomal Thiol reductase (GILT), which differentially regulates HLA class II-restricted antigen processing and presentation. The purpose of this study was to investigate the mechanisms by which GILT insertion influences CD4+ T cells recognition of human melanoma cells via the HLA class II pathway. Biochemical analysis of melanoma cells showed that GILT expression upregulated the HLA class II components such as HLA-DM and invariant chain while class II protein expression remained unchanged. An increase in endolysosomal cathepsin protein expression and activity was also observed in melanoma cells transfected with GILT. Data obtained from biochemical and functional assays suggest that GILT insertion may help melanoma cells generate more antigenic determinants that are readily accessible to class II loading and presentation to CD4+ T cells. Taken together, these data suggest that GILT-inserted melanoma cells could be used in the design of whole cell vaccines for the treatment of metastatic melanoma.

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 4787.
Abstract 4790: Docetaxel modulates phenotype of human carcinoma cells, including drug-resistant tumor cells, resulting in enhanced killing by CTLs
Authors: Garnett Charlie T. , Farsaci Benedetto , Schlom Jeffrey , Hodge James W.
Published: February 2011

Purpose: Recent studies have reported that docetaxel, in addition to its direct cytostatic effects on murine tumors, can modulate immune cell populations in nontumor-bearing mice and enhance CD8+ T-cell responses. This study investigated docetaxel's ability to alter human tumor phenotype and sensitize tumor cells to immune attack.

Experimental Design: We examined 18 human carcinoma cell lines (4 breast, 3 prostate, 2 lung, 2 ovarian, and 7 colon) for docetaxel-induced changes in surface protein expression and sensitivity to CTL-mediated lysis. We also analyzed docetaxel-resistant tumor cells. After in vitro treatment with docetaxel, we examined surface expression of 5 molecules involved in T cell-mediated attack by fluorescence-activated cell sorting analysis, and measured the sensitivity of tumor cells to lysis by antigen-specific CD8+ CTLs, cell death, and inhibition of proliferation.

Results: Of the 18 cell lines tested, 15 (83%) up-regulated one or more of the surface molecules Fas, ICAM-1, MUC-1, CEA, and MHC class I post-docetaxel treatment. Killing by either CEA-specific or MUC-1-specific HLA-A2-restricted CD8+ CTLs was significantly enhanced in 6 of 9 docetaxel-treated HLA-A2+ tumor cell lines compared with untreated cell lines. Furthermore, tumor cells that were resistant to direct docetaxel cytotoxicity modulated phenotype and became more sensitive to CTL killing after treatment with docetaxel.

Conclusions: The results of this study suggest that docetaxel can sensitize human tumor cells to immune recognition and attack, even cells resistant to the direct cytotoxic effects of the drug. These findings establish a rationale for the combined use of vaccine and taxane based chemotherapy.

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 4790.
Abstract 4794: Tn (GalNAcα1-O-Ser/Thr) in serum mucin: a potential cancer biomarker
Authors: Hwang Jaulang , Chiang Hsiao-Ling , Lin Chi-Yu , Jan Fan-Dan , Chen Chiao-En , Hsu Chia-Tse , Nieh Shin , Lin Chun-Cheng
Published: February 2011

Mucin-related carbohydrate epitope, Tn (GalNAcα1-O-Ser/Thr), is expressed in epithelial tumors including breast, prostate, and ovarian cancer. Since the expression of Tn was shown to define the stage, rate, and phenotype of tumor progression as well as the diagnosis, Tn may offer as useful information for prognostic purposes. However, Tn-based tumor diagnosis requires the immunohistochemistry (IHC) staining of tumor tissue. A simple and noninvasive assay for tumor diagnosis is desirable. This study is taken an effort to examine whether Tn in serum mucin can be used as biomarker for cancer diagnosis. To reach this goal, we must have an anti-Tn antibody with high affinity and high specificity. This study presents a novel carrier protein containing a binding domain to the receptor of antigen presenting cells and cysteine-rich repeat peptide to serve as docking sites for conjugating Tn, as a result, to collaboratively activate T-cells and B-cells. This novel carrier protein after conjugation with Tn can effectively elicit high titer of IgG1 antibodies rather than IgM against Tn with high specificity in all immunized mice and rabbits. Applying this anti-Tn antibody, we observed that Tn expression by IHC assay is highly significantly correlated with the malignancy of tumors. We then applied anti-Tn antibody to detect the Tn in serum mucin of 12 lung cancer patients. The results showed that the levels of Tn were high in serum mucin of 11 out of 12 lung cancer patients, while the levels of serum mucin Tn are relatively low in normal people, suggesting that the levels of Tn in serum mucin may be a potential cancer biomarker.

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 4794.
Abstract 4804: Identification of a functional network of human epigenetic silencing factors
Authors: Poleshko Andrey S. , Einarson Margret B. , Shalginskikh Natalia , Zhang Rugang , Adams Peter D. , Skalka Anna Marie , Katz Richard A.
Published: February 2011

Epigenetic silencing directs transcriptional shutoff of specific genes during development and cellular differentiation. This process is mediated by epigenetic “marks” including DNA methylation and a variety of posttranslational histone modifications (e.g. methylation). Errors in placement or removal of epigenetic marks can drive epigenetic silencing and tumorigenesis. Inhibitors of DNA methyltransferase (DNMT) and histone deacetylase (HDAC) enzyme families (DNMTi and HDACi, respectively) can reverse epigenetic silencing and produce anti-tumor effects, possibly through reactivation of silent tumor suppressor genes (so-called epigenetic therapy). As these inhibitors show little specificity within enzyme families, their precise mechanisms of action are not well understood. To identify cellular factors involved in maintenance of epigenetic silencing, HeLa cells harboring epigenetically silent GFP reporter genes were interrogated with an siRNA library targeting predicted epigenetic regulators, including potential activators, silencers, chromatin remodelers, and ancillary factors. Using this approach, individual, or combinatorial requirements for specific epigenetic silencing factors can be detected by measuring GFP reactivation after siRNA-based factor knockdown. In our analyses, we identified a specific subset of epigenetic factors that are candidates for participation in a functional epigenetic silencing network in human cells. These factors include the histone deacetylase HDAC1, the de novo DNA methyltransferase DNMT3A, components of the Polycomb PRC1 complex (RING1, HPH2), and the histone lysine methyltransferases KMT1E and KMT5C. Roles were also detected for two TRIM protein family members, the cohesin component Rad21, and the histone chaperone CHAF1A (CAF-1 p150). Remarkably, combinatorial knockdown of factors was not required for reactivation, indicating little functional redundancy. Consistent with this interpretation, knockdown of either KMT1E or CHAF1A resulted in a loss of multiple histone repressive marks and concomitant gain of activation marks on the promoter during reactivation. These results reveal how functionally diverse factors may cooperate to maintain gene silencing during normal development or in disease. Furthermore, the findings suggest an avenue for discovery of new targets for epigenetic therapies.

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 4804.
Abstract 4807: FOXD3 regulates Rnd3 and invasion in mutant BRAF melanoma cells
Authors: Katiyar Pragati Dixit , Abel Ethan V. , Aplin Andrew E.
Published: February 2011

Melanoma occurs due to the transformation of melanocytes and is the deadliest form of skin cancer with an estimated 68,720 new cases and 8,650 deaths in 2009. During radial growth phase (RGP) that is confined to the epidermis and papillary dermis, melanoma is treatable by surgical excision. However, dermal invasion during the vertical growth phase (VGP) is associated with a worse prognosis. The mechanisms contributing to aberrant melanoma invasion are poorly elucidated. Activating mutations in BRAF (a serine kinase) are found in approximately 60% of melanoma cases. Mutant BRAF is required for the invasion and changes in actin cytoskeleton associated with invasion are in part controlled by Rnd3, a BRAF regulated Rho family GTPase. Melanocytes derive from the neural crest, a multipotent population of migratory cells. Pluripotency and self-renewal of neural crest cells is regulated by the transcription factor FOXD3. Since we have previously shown that BRAF inhibition results in up-regulation of FOXD3 and down-regulation of Rnd3, we examined the role of FOXD3 in regulation of Rnd3 in cellular migration and invasion. We used inducible lentiviral-based expression of FoxD3 in various mutant BRAF melanoma cell lines (WM793 and A375). Inducible expression of FoxD3 in WM793mFoxD3 and A375mFoxD3 was confirmed by western blot. Boyden chamber with or without matrigel coating and 3D tumor spheroid collagen assays were used to study cellular migration and invasion in a dermal mimetic microenvironment. We observed a significant decrease in the migration and invasion in WM793 (VGP) and A375 (metastatic) melanoma cell lines and a decreased spheroids formation in the soft agar colony formation assay after FoxD3 induction. This inhibition of migratory/ invasive properties correlated with a FOXD3-dependent down-regulation of Rnd3 both at protein and mRNA level. Our study for the first time showed that FoxD3 expression down-regulates Rnd3 that increased actin stress fiber formation and decreases migration, invasion and spheroids formation in the metastatic melanoma cells. This study is relevant to the current challenge of understanding mechanism of BRAF regulation of invasion and provides additional targets for therapeutic intervention for the effective treatment of melanoma.

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 4807.
Abstract 4837: Short-chain fatty acids induced autophagy serves as an adaptive strategy for retarding mitochondria-mediated apoptotic cell death
Authors: Tang Yong , Chen Yakun , Jiang Hongmei , Nie Daotai
Published: February 2011

Short-chain fatty acids (SCFAs) are the major by-products of the bacterial fermentation of undigested dietary fiber in the human large intestine. The role of SCFAs, mostly propionate and butyrate, in colon cancer apoptotic cell death and cell proliferation inhibition has been well studied. Herein we demonstrate that, in addition to apoptotic cell death, propionate and butyrate induce another type of cell death termed “autophagy” in human colon cancer cells. Propionate-treated cells exhibited extensive characteristics of autophagic proteolysis: increased LC3-I to LC3-II conversion and reduced expression of p62/SQSTM1; increased acidic vesicular organelle development as manifested by dramatic increase in punctate GFPLC3, LysoTracker and MDC staining. Propionate-induced autophagy was associated with decreased mTOR activity and enhanced AMP kinase activity, two events known to be linked to autophagy. The elevated AMPKa phosphorylation is believed to have been caused by cellular ATP depletion due to mitochondrial dysfunction involving induction of mitochondrial permeability transition, as evidenced by the loss of mitochondrial membrane potential and overproduction of reactive oxygen species. In this context, mitochondria biogenesis was initiated to recover cellular energy homeostasis. Importantly, when autophagy was prevented at an early stage by 3-methyladenine, or when autophagic degradation was inhibited at a late stage by Chloroquine, the colon cancer cells became sensitized toward propionate induced apoptosis through activation of caspase 7 and its downstream effector caspase-3. Potentiation of cell death was also observed when autophagy was abolished using shRNA against the autophagic gene ATG5. These observations indicate that propionate-triggered autophagy serves as an adaptive strategy for retarding mitochondria-mediated apoptotic cell death. As SCFAs widely exist in the human large intestine, application of an autophagy inhibitor, such as Chloroquine, is expected to enhance the therapeutic efficacy of SCFAs in inducing tumor cell apoptosis.

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 4837.
Abstract 4859: Statin-induced autophagy in prostate cancer cells
Authors: Parikh Ankur , Childress Chandra , Lin Qiong , Rukstalis Daniel , Yang Wannian
Published: February 2011

Statins, a class of inhibitors of 3-hydroxyl-3-methylglutaryl coenzyme A (HMG-CoA) reductase, are commonly prescribed medications for treatment of hypercholesterolemia. Epidemiological studies have shown that statin use decreases the incidence of advanced prostate cancer. Here we report that atorvastatin (Lipitor), a broadly prescribed statin, induces autophagy and rapid cell death in androgen receptor (AR)-negative prostate cancer PC3 cells. Atorvastatin treatment of PC3 cells for 40 hrs increased expression of LC3-II by more than 10 fold in a dose-dependent manner. Treatment of the cells with pepstatin A and E64-d, the autophagic protease inhibitors, dramatically increased atorvastatin-dependent LC3-II expression level, indicating that atorvastatin induced autophagic flux. In addition, atorvastatin treatment caused rapid death of PC3 cells. Atorvastatin-induced autophagy and rapid cell death were reversed by addition of geranylgeraniol, not farnesol, in culture medium, indicating that atorvastatin-mediated inhibition of geranylgeranyl biosynthesis causes autophagy and cell death. Furthermore, atorvastatin did not induce autophagy or cell death in normal prostate RWPE1 cells and induced only a minor autophagic response in AR-positive prostate cancer LNCaP cells. Thus, our studies demonstrate that statins induce autophagy and autophagy-associated cell death in PC3 cells, likely through inhibition of geranylgeranylation, and suggest that autophagic response to statins may partially underlie the protective effects of statins on prostate cancer. Importantly, these findings highlight additional mechanisms by which statins might be used for therapy of prostate cancer.

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 4859.
Abstract 4870: A Novel gamma-Lactam-Based Histone Deacetylase Inhibitor Potently Inhibits the Growth of Human Breast and Renal Cancer Cells
Authors: Park Sunyoung , Lee Jae Cheol , Jeon Ye Ji , Lee Hyunwoo , Kim Munkyung , Han Jeung-Whan
Published: February 2011

We evaluated the novel gamma-lactam-based analogue, KBH-A145, for its anticancer activities. KBH-A145 markedly inhibited histone deacetylase (HDAC) activity in vitro and in vivo to an extent comparable to suberoylanilide hydroxamic acid (SAHA). The proliferation of various types of cancers was significantly suppressed by KBH-A145, among which MDA-MB-231 and MCF, human breast cancer cells and ACHN human renal cancer cells, were most sensitive. This was accompanied by induction of p21WAF1/Cip1 through compromised recruitment of HDAC1, which leads to hyperacetylation of its promoter region and thus arrested both cells in the G2/M phase. Interestingly, this compound induced apoptosis of MDA-MB-231 cells, but not ACHN cells, through cleavage of poly(ADP-ribose) polymerase (PARP). Taken together, these results show that this novel gamma -lactam-based HDAC inhibitor potently inhibits the growth of human breast and renal cancer cells. Thus KBH-A145 is a potential therapeutic agent for the treatment of these types of cancer.

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 4870.
Abstract 4871: Genomic amplifications in ovarian carcinoma are associated with specific histone modifications
Authors: Thiaville Michelle M. , Wang Tian-Li , Shih Ie-Ming , Chen Lily , Xiong Jianghui , Xuan Jason J.
Published: February 2011

Genomic amplification is a frequent molecular genetic alteration in many cancer types that results in upregulation and thus activation of oncogenes located in the amplified regions. However, the mechanism by which amplified genes are upregulated is poorly understood. We hypothesized that epigenetic regulation of gene expression was important for activation in addition to the increased DNA copy number for genes within amplified genomic loci. To test this hypothesis, we used ovarian cancer as an example because it is a highly lethal disease and, more importantly, ovarian cancer cells are characterized by a high level of genomic instability as reflected by widespread DNA copy number changes. We analyzed the data from chromatin immunoprecipitation array (Chip-chip) and single nucleotide polymorphism (SNP) array to determine the correlation between specific histone modifications and genome-wide DNA copy number alterations in OVCAR3 ovarian cancer cells and ovarian surface epithelial cell culture. Among 8 histone marks examined, representing both heterochromatic and euchromatic chromatin, we identified the strongest correlation between increased DNA copy number and the active histone marks, histone H4 acetylation at lysine 5 (p-value 7.8×10^-6; FDR 5.2×10^-5) and lysine 12 (p-value 7.6×10^-5; FDR 2.6×10^-4). In contrast, there was no significant correlation between DNA amplification and repressive histone marks including histone H3 methylation at lysines 9 and 27. These correlations were validated by quantitative real-time PCR of ChIP samples at confirmed amplified regions on chromosomes 11 and 19, which harbor the RSF1 and AKT2 oncogenes. Furthermore, all genes within the amplicons were overexpressed in the OVCAR3 cell line harboring the amplicons as compared to a normal ovarian surface epithelial cell line. By using ovarian cancer as a disease model, our results indicate that an amplicon-associated specific histone modification pattern facilitates gene expression and suggest that both genetic (DNA copy number gain) and epigenetic (active histone marks) events contribute to upregulation of amplified genes which may ultimately contribute to the development of human cancer.

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 4871.
Abstract 4879: Identification of the hSET1 as a unique marker to cancer cells
Authors: Yadav Sushma , Singahl Sharad S. , Singhal Jyotsana , Awasthi Sanjay
Published: February 2011

Our recent studies have shown that human SET1, a key element of highly conserved multi-protein histone methyl transferase (HMT) complex known to catalyze methylation of histone H3 lysine 4 (H3K4) and regulating expression of specific genes important for the malignant phenotype, differentially over-expressed in the cancer cells. RT-PCR competition assay were developed using oligonucleotides, designed from the conserved sequences from the flanking regions of hSET1 and have shown that the sequences of hSET1 are unique to the malignant tumor tissues. The studies have been extended to the cultured cells and hSET1 has been shown to be differentially over-expressed in the malignant cells as compared to the normal cells at the RNA as well as protein level.

The potential importance of these observations is underscored by our recently published studies showing complete regression of human colon cancer xenografts in nude-mice treated with phosphorothioate antisense to cause near complete depletion of SET1 in the animal. No significant adverse effects were seen, and all animals treated with antisense had regression of already established xenografts after i.p. injection of SET1 directed phosphorothioate antisense. In contrast, tumor progression was not affected by a paired scrambled antisense. These findings indicate that amplification by RT-PCR of specific circulating tumor-specific ribonucleotides may be a powerful tool for early detection of cancer, and perhaps a means for selecting patient-specific targeted therapies.

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 4879.
Abstract 4897: Genome-wide analysis of CGIs in bladder cancer identifies novel epigenetic biomarkers for diagnosis and follow-up
Authors: Kandimalla Raju , Tilborg Angela Van , Kompier Lucie , Stumpel Dominique J.P.M , Zwarthoff Ellen C.
Published: February 2011

Epigenetic modifications have been shown to contribute to the pathogenesis of various cancers including bladder cancer. Hypermethylation in cancer is often found in CGIs in the 5′ regions of genes. These DNA modifications may serve as useful biomarkers, both for diagnostic and prognostic purposes. Although the list of aberrantly methylated genes in cancer is expanding, only a few genes so far were investigated for their usefulness as tumor biomarkers for early diagnosis and risk assessment of bladder cancer. Thus, a large scale (genome wide) screening of aberrant methylation of CGIs is needed to identify bladder-specific epigenetic markers.

In this study, we performed a genome wide screening for DNA methylation in different subtypes of bladder cancer using differential methylation hybridization (DMH) coupled with Agilent 244k human CpG island microarrays. We next validated the genome-wide data on a 384-plex custom Illumina Golden Gate Methylation Assay (GGMA), which is based on bisulfite conversion.

We found and validated a large number of possible novel epigenetic biomarkers for early detection and prognosis of bladder cancer. We also observed that subgroups of bladder tumors cluster separately due to their different methylation patterns suggesting possible differences in pathogenesis. Our data clearly shown that the adjacent CpG loci within a CGI were co-methylated. In contrast, CGIs neighboring a methylated island were usually not methylated. The data showed no bias toward promoter methylation as the relative proportion of methylated islands in genes was similar to those encompassing promoter regions. We observed that 70% of the methylated genes are downregulated in bladder cancer. Moreover, gene body methylation also seems to be negatively correlated with gene expression. Interestingly, we found an overrepresentation of methylated genes in those genes that are the target of polycomb group protein complexes in embryonic stem cells. Further validation of selected CGIs on a separate group of bladder cancers on a custom Illumina Golden Gate Methylation assay (GGMA) allowed us to confirm 70 % of CGIs differentiating bladder cancers from normal cells, besides validating CGIs discriminating subgroups of bladder tumors.

In conclusion, this is the first genome-wide study on bladder cancer which identified potential methylation target genes that provides putative biomarkers that may be correlated with disease course as well as insight into the pathogenesis of bladder cancer subtypes.

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 4897.