bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 2554: Constitutive short telomere length and lung cancer risk: a large case- control study.
Authors: Sanchez-Espiridion Beatriz , Gu Jian , Chang David W. , Chang Joe Y. , Lu Charles , Roth Jack A. , Wu Xifeng
Published: August 2014

Background: Telomeres plays a key role in the maintenance of chromosomal stability and integrity. Telomere dysfunction is a common crucial event in malignant transformation and tumorigenesis. Short telomere length in surrogate tissues (peripheral blood leukocytes, or PBLs) has been associated with increased risks of several cancers. In this study, we used a large case control study to evaluate the association of overall telomere length in PBLs with the risk of lung cancer.

Methods: We measured the overall telomere lengths in PBLs using real-time quantitative PCR method in a large case-control study with 769 Caucasian lung cancer cases and 769 age, gender, and ethnicity matched healthy controls Wilcoxon rank sum test was used to compare the differences between case patients and control subjects. Unconditional multivariate logistic regression analysis was used to assess the association between telomere length and lung cancer risk. In addition, the effect of age, gender and smoking status was evaluated and correlation analyses between variables were performed.

Results: As expected, telomere length was inversely correlated with age in both cases and controls. Lung cancer patients had significantly shorter overall telomere lengths (mean ± standard deviation: 1.20 ±0.37 versus 1.25 ±0.35 p =0.002) than controls, which was only evident in men (1.15 ±0.36 versus 1.24 ±0.36 p <0.001) but not in women. Multivariate logistic regression analysis showed that short overall telomere length was associated with a dose-dependent increase in lung cancer risk. Compared to the individuals within the highest quartile of telomere length, the OR for those within the 3rd, 2nd and 1st quartiles was 0.88 (95% CI 0.65-1.18), 1.08 (95% CI 0.80-1.44) and 1.49 (95% CI 1.12-1.99), respectively (p for trend < 0.001). This effect was more pronounced in current and former smokers (p for trend < 0.001) than in nonsmokers. There was a significant interaction between smoking and overall telomere length in elevating lung cancer risk (p for interaction <0.001).

Conclusions: This is the largest epidemiological study to evaluate constitutive telomere length and lung cancer risk. Our data strongly support the role of telomere dysfunction in lung carcinogenesis, highlighting its specific interaction with smoking.

Citation Format: Beatriz Sanchez-Espiridion, Jian Gu, David W. Chang, Joe Y. Chang, Charles Lu, Jack A. Roth, Xifeng Wu. Constitutive short telomere length and lung cancer risk: a large case- control study. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2554. doi:10.1158/1538-7445.AM2013-2554
Abstract 2557: Genetic variants in microRNA genes and breast cancer risk.
Authors: Beeghly-Fadiel Alicia C. , Sung Hyuna , Zhang Ben , Choi Ji-Yeob , Delahanty Ryan J. , Long Jirong , Gao Yu-Tang , Lu Wei , Cai Qiuyin , Shu Xiao Ou , King Daehee , Zheng Wei
Published: August 2014

microRNA (miRNA) are small noncoding molecules that function as regulators of the genome. Genetic variants in miRNA binding sites and miRNA genes have begun to be evaluated in relation to disease risk; however, no studies have yet comprehensively evaluated miRNA variants in relation to breast cancer risk. Using a two stage study design, and genome-wide association study (GWAS) data, we evaluated genetic variants within 1,425 miRNA genes (±5kb). In Stage 1, a total of 2,213 common genetic variants were evaluated among 2,876 breast cancer cases and 2,285 controls using data from the Shanghai Breast Cancer Genetics Study. Nominally significant associations (P value ≤0.05) were found for 108 variants in 96 genetic loci (r²≥0.6). In Stage 2, 94 variants in 84 loci were evaluated among 2,225 cases and 2,052 controls from the Seoul Breast Cancer Study; nine variants in eight loci had nominally significant associations. In analyses of the two study stages combined, 14 loci had highly significant associations (P value ≤0.01) and 19 additional loci had significant associations (P value ≤0.05) with breast cancer risk, all with consistent directions of association between the two study stages. These 36 variants in 33 loci have been mapped to 16 miRNA genes, many in the promoter regions. Based on our findings, genetic variants in miRNA genes are likely to contribute to breast cancer susceptibility.

Citation Format: Alicia C. Beeghly-Fadiel, Hyuna Sung, Ben Zhang, Ji-Yeob Choi, Ryan J. Delahanty, Jirong Long, Yu-Tang Gao, Wei Lu, Qiuyin Cai, Xiao Ou Shu, Daehee King, Wei Zheng. Genetic variants in microRNA genes and breast cancer risk. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2557. doi:10.1158/1538-7445.AM2013-2557
Abstract 256: Elucidating the role of ARID3B in ovarian cancer stem cells.
Authors: Deneke Victoria E. , Roy Lynn , Dahl Richard , Cowden Dahl Karen D.
Published: August 2014

Ovarian cancer is the fifth leading cause of cancer death among US women and accounts for more deaths than any other cancer of gynecological origin. In light of the lethality, it is critical to discover and understand the common molecular characteristics in ovarian cancer. Our lab demonstrated that ARID3B, a member of the AT-rich interactive domain family of proteins, is overexpressed in ovarian cancer. Furthermore, ARID3B is essential for embryonic development and is present in embryonic stem cells. Overexpression of ARID3B in ovarian cancer cells leads to increased tumor growth and decreased survival in xenograft studies. Therefore, we hypothesize that ARID3B regulates cancer stem cell production, which enhances tumorigenesis. We have found that stem-cell marker CD133 is upregulated in ovarian cancer human cell line SKOV3IP overexpressing ARID3B. We are currently assessing the mechanism for ARID3B regulation of ovarian cancer stem cells using in vitro models. Determining the role of ARID3B in cancer stem cells may help us better understand the molecular mechanisms that regulate tumor initiation, chemoresistance, and ovarian cancer progression.

Citation Format: Victoria E. Deneke, Lynn Roy, Richard Dahl, Karen D. Cowden Dahl. Elucidating the role of ARID3B in ovarian cancer stem cells. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 256. doi:10.1158/1538-7445.AM2013-256
Abstract 2563: Identification and functional characterization of a novel UGT2A1 splice variant: Potential importance in tobacco-related cancer susceptibility .
Authors: Bushey Ryan T. , Chen Gang , Lazarus Philip
Published: August 2014

UGT2A1 is a phase II enzyme highly expressed in the respiratory and aerodigestive tracts. In the present study, a novel exon 3 deletion splice variant for UGT2A1 (termed ‘UGT2A1Δexon3’) was characterized. As determined by reverse-transcription polymerase chain reaction, UGT2A1Δexon3 was shown to be co-expressed with wild-type UGT2A1 in various tissues including lung, trachea, larynx, tonsil, and colon. The mRNA expression ratio of UGT2A1Δexon3:wild-type UGT2A1 was highest in colon (0.79±0.08) and lung (0.42±0.12) as determined by real-time PCR; splice variant protein (termed ‘UGT2A1_i2’) to wild-type protein (termed ‘UGT2A1_i1’) ratios were in the range of 0.5-0.9 in these tissues as determined by Western blot analysis using an UGT2A1-specific antibody. In contrast to the UGT2A1 wild-type isoform, homogenates prepared from UGT2A1_i2-over-expressing HEK293 cells exhibited no glucuronidation activity against PAHs, including benzo(a)pyrene-7,8-dihydrodiol (B(a)P-7,8-diol). An inducible in vitro system was created to determine the effect of UGT2A1_i2 expression on UGT2A1_i1 activity. Increasing UGT2A1_i2 levels resulted in a significant (p<0.01) decrease in the UGT2A1_i1 Vmax against 1-hydroxy (OH)-pyrene, 3-OH-B(a)P and B(a)P-7,8-diol; no significant changes in KM were observed for any of the three substrates. Co-immunoprecipitation experiments suggested the formation of UGT2A1_i1 and UGT2A1_i2 hetero-oligomers and UGT2A1_i1 homo-oligomers; co-expression of UGT2A1_i1 or UGT2A1_i2 with other UGT1A or UGT2B enzymes caused no change in UGT1A or UGT2B glucuronidation activity. These data suggest that a novel UGT2A1 splice variant regulates UGT2A1-mediated glucuronidation activity via UGT2A1-specific protein-protein interactions, and that expression of this variant could play an important role in the detoxification of carcinogens within target tissues for tobacco carcinogenesis.

Citation Format: Ryan T. Bushey, Gang Chen, Philip Lazarus. Identification and functional characterization of a novel UGT2A1 splice variant: Potential importance in tobacco-related cancer susceptibility . [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2563. doi:10.1158/1538-7445.AM2013-2563
Abstract 2568: Genetic association of POU5F1B at 8q24 with prostate cancer.
Authors: Breyer Joan P. , Smith Jeffrey R.
Published: August 2014

Numerous genetic variants at 8q24 have been associated with risk for multiple common cancers, most prominently for prostate cancer. POU5F1B is a retrotransposed copy of the master stem cell factor OCT4, and one of few known genes within the 8q24 interval. While OCT4 is expressed selectively in embryonic stem cells, POU5F1B retains its open reading frame and has been shown to be expressed in cancers. Ectopic expression of OCT4 blocks progenitor cell differentiation and causes dysplasia, raising the possibility that aberrant expression of POU5F1B might have analogous effects. Because POU5F1B sequence is non-unique, a potential contribution of POU5F1B genetic variation to cancer risk has not been investigated in prior GWAS. We evaluated genetic variants of POU5F1B for association with prostate cancer within a case-control study of familial prostate cancer at Vanderbilt University that included 830 familial prostate cancer probands, and 830 age-matched control probands without a personal or family history of prostate cancer. Our study identified four missense variants within POU5F1B, and eight haplotypes of > 1% frequency. G176E was associated with prostate cancer (P = 3.1 x 10−4) and was in LD with GWAS SNP rs6983267 (r2 = 0.69). The minor allele (encoding glutamate) uniquely marked a single haplotype (the most common) with an inverse association with prostate cancer (P = 5.7 x 10−4, OR = 0.78 (95%CI 0.7-0.9)). As expected, the haplotype association was correlated with that of GWAS SNP rs6983267. A second haplotype differing from the first only at G176E (encoding glycine) was independently associated with risk of prostate cancer (P = 5.5 x 10−7, OR = 1.91 (95%CI 1.5-2.5)). However, glycine would also be encoded at this position by all other haplotypes, none carrying a risk effect. The risk haplotype was tagged by the pair of missense variants, G176E (glycine) and E238Q (glutamine). In a single allele analysis, the latter variant had no apparent association with prostate cancer. The risk effect of the former adjusted for the latter was OR = 2.12 (95%CI 1.6-2.7), P = 1.7 x 10−8; the risk effect of the latter adjusted for the former was OR = 1.79 (95%CI 1.4-2.3), P = 9.4 x 10−6. The two missense variants would alter each of the DNA-binding domains: one altering a highly conserved site with a non-conservative substitution, and the other abrogating a kinase site known to physiologically regulate other POU transcription factors. Our data suggest that combinations of these variants may be associated with risk of prostate cancer and warrant further investigation of the potential role of POU5F1B in the 8q24 cancer associations.

Citation Format: Joan P. Breyer, Jeffrey R. Smith. Genetic association of POU5F1B at 8q24 with prostate cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2568. doi:10.1158/1538-7445.AM2013-2568
Abstract 258: Growth factor signaling is critical in the maintenance of cancer stem cell population in head and neck squamous cell cancer.
Authors: Leong Hui Sun , Sew Pui Hoon , Chong Fui Teen , Tan Daniel Shao-Weng , Iyer Narayanan Gopalakrishna
Published: August 2014

Tumor heterogeneity is an important concept in the carcinogenesis of solid tumors, and forms the background for the cancer-stem cell (CSCs) hypothesis. Emerging data suggests however that there is plasticity within various cancer sub-populations, and that CSCs exists in a contextually regulated equilibrium, which is multi-directional and less rigid than previously hypothesized. The aim of this study was to establish an in vitro system that recapitulates stem cell plasticity in head and neck squamous cell cancers (HNSCC), and identify factors that play a role in the maintenance and re-population of CSCs.

Tumor spheres were established using patient-derived tumor cells via anchorage-independent cell culture techniques. RT-PCR showed higher expression of KLF4, SOX2 and Nanog in tumor spheres compared to monolayer culture cells. Cells grown as tumor spheres were more resistant to γ-radiation, 5-fluorouracil, cisplatin and etoposide treatment compared to cells grown in monolayer culture. Using the ALDEFLUOR assays to identify CSCs, we showed that more cells in tumor spheres had high aldehyde dehydrogenase (ALD+ cells) activity. Monolayer cultures were subject to single cell cloning to generate clones with high and low ALD+ fractions. As expected, ALDHigh clones showed higher expression of stem cell markers Oct4, Bmi1 and Nanog and EMT markers N-Cadherin, Slug, Snail, β-Catenin, Vimentin compared to ALDLow clones. When ALDHigh clones from HNSCC cells were cultured over time, ALD+ fractions were found to reduce gradually and equilibrate at a specified ALD+ fraction specific to each cell line grown in regular culture media. When growth factors EGF and/or insulin were added to the media, ALD+ fractions could be maintained at higher levels as compared to baseline. ALDHigh clones also showed increased EGFR and IGF-1R phosphorylation when grown in regular culture conditions, with increased activation of downstream factors involving the AKT and ERK pathways compared with ALDLow clones. Blocking these pathways using specific inhibitors against EGFR and IGFR reduced stem cell fractions drastically.

Taken together, these results show that HNSCC CSCs exhibit plasticity, where the maintenance of the stem cell fraction was dependent on the EGF and IGF pathways, which are therefore vulnerable to therapeutic targeting.

Citation Format: Hui Sun Leong, Pui Hoon Sew, Fui Teen Chong, Daniel Shao-Weng Tan, Narayanan Gopalakrishna Iyer. Growth factor signaling is critical in the maintenance of cancer stem cell population in head and neck squamous cell cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 258. doi:10.1158/1538-7445.AM2013-258
Abstract 2589: The P110 subunit of PI3-K is a therapeutic target of acacetin in skin cancer.
Authors: Kim Jon Eun , Jung Sung Keun , Byun Sanguine , Lee Sung-Young , Kim Myoung Ok , Lim Tae Gyu , Bode Ann M. , Lee Hyong Joo , Lee Ki Won , Dong Zigang
Published: August 2014

Verifying potential target proteins of phytochemicals is important for explaining their health benefits. In the present study, we examined the chemopreventive effect and molecular target of acacetin, which is a flavonoid from Robinia Psuedoacacia also known as Black Locust. Treatment with acacetin significantly inhibits EGF-induced transformation of JB6 P+ cells. Western blot assay results revealed that acacetin suppresses EGF-induced phosphorylation of Akt/p70S6K, which is a well-known downstream signaling molecule of phosphatidylinositol 3-kinase (PI3-K). In vitro kinase and pull-down assay results showed that acacetin significantly inhibits PI3-K activity by direct binding. Additionally, acacetin also attenuated EGF-induced PI3-K activity and binds with PI3-K in JB6 P+ cells. Acacetin showed significant effects against anchorage-dependent and -independent cell growth in cells displaying higher PI3-K activity compared with those exhibiting lower PI3-K activity. Binding assay data and computational modeling showed that acacetin binds in an ATP-competitive manner with the p110 kinase domain of PI3-K and interacts with Val828, Glu826 Asp911 Trp760, Ile777, Ile825, Tyr813, Ile910 and Met900. Acacetin reduced SK-MEL-28 xenograft tumor growth and phosphorylation of Akt in vivo. Overall, these results indicate that acacetin is an ATP competitive PI3-K inhibitor and might be a promising chemopreventive agent targeting PI3-K activity.

Citation Format: Jon Eun Kim, Sung Keun Jung, Sanguine Byun, Sung-Young Lee, Myoung Ok Kim, Tae Gyu Lim, Ann M. Bode, Hyong Joo Lee, Ki Won Lee, Zigang Dong. The P110 subunit of PI3-K is a therapeutic target of acacetin in skin cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2589. doi:10.1158/1538-7445.AM2013-2589
Abstract 259: Novel biliary tract cancer stem cell biomarker TAGLN2 regulates migration via c-met signaling cascades in biliary tract cancer cells.
Authors: Park Soo Been , Kim Sun A , Song Si Young
Published: August 2014

Background/Aims : Biliary tract cancer is one of the lethal malignancy. Most biliary tract cancer is diagnosed at advanced stages and have poor prognosis. Currently, there are no standard biomarkers and chemotherapeutic agents for biliary tract cancers. In order to find the biomarkers and therapeutic targets for biliary tract cancer, we have focused on the cancer stem cells (CSCs) with tumor initiating/self renewing/metastatic capacity and chemo/radio-resistance. In this study, we investigated the function of biliary tract CSC related biomarker TALGN2 discovered from comparision of cDNA microarray between sphere and adherent cell populations of biliary tract cancer cell lines.

Methods : Analysis using cDNA microarray between sphere and adherent cell populations and selection of CSC specific biomarkers were performed. Among them, we selected TAGLN2 as a biliary CSC related gene. TAGLN2 expression was confirmed by RT-PCR, western blot and immunohistochemistry. To evaluate the function of TAGLN2 in biliary carcinogenesis, we performed targeted knockdown via siRNA in SNU1196 biliary tract cancer cell line.

Results : The expression of stemness and c-met signaling cascades were up-regulated in sphere cells compared with adherent cells. TAGLN2 was also up-regulated in sphere cells. TAGLN2 was highly expressed in most of biliary tract cancer cell lines and biliary tract cancer tissues. TAGLN2 knockdown cells showed decreased cell migration and increased chemosentitivity compared with mock cells. In addition, we found that c-met signaling cascades including PI3K and MAPK were inactivated in TAGLN2 knockdown cells.

Conclusions : These results suggest that biliary tract CSC biomarker TAGLN2 is implicated in biliary tract cancer progression and TAGLN2 may be a potential biomarker and therapeutic target for biliary tract cancer.

Citation Format: Soo Been Park, Sun A Kim, Si Young Song. Novel biliary tract cancer stem cell biomarker TAGLN2 regulates migration via c-met signaling cascades in biliary tract cancer cells. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 259. doi:10.1158/1538-7445.AM2013-259
Abstract 261: Podocalyxin-like 1 promotes stemness and metastasis of cancer cells through activating cortactin.
Authors: Lin Cheng-Wei , Sun Min-Shiou , Liao Mei-Ying , Yu John , Chiou Li-Ting , Wu Han-Chung
Published: August 2014

Cancer stem cells (CSCs) are involved in tumor-initiation, self-renewal, and metastasis. CSCs share many similar biological properties with embryonic stem cells (ESCs). Currently, there still lacks a biomarker that can specifically identify CSCs. Therefore, the signaling mechanism underlying the metastatic process due to CSCs is still unclear. In the present study, we used hybridoma to identify cell surface biomarker that was coexpressed on both ESCs and cancer cells. We found that podocalyxin-like 1 (PODXL) was expressed abundantly on both ESCs and cancer cells. The expression of PODXL, which was upregulated in tumorsphere, was found to be associated with CSCs markers. Additionally, overexpression of PODXL was correlated with lymph node metastasis and cancer malignancy. Knockdown of PODXL suppressed tumor self-renewal, invasiveness, and metastasis. Further study of its molecular mechanism revealed that PODXL induces focal adhesion kinase activation, F-actin polymerization, and invadopodia formation by interacting with and activating cortactin. Collectively, we found that PODXL promotes tumor self-renewal and initiation and that the elevation of PODXL enhances local tumor cells invasiveness and distant organ metastasis. Therefore, PODXL might be a biomarker for CSC and a potential target for the development of CSC therapeutics.

Citation Format: Cheng-Wei Lin, Min-Shiou Sun, Mei-Ying Liao, John Yu, Li-Ting Chiou, Han-Chung Wu. Podocalyxin-like 1 promotes stemness and metastasis of cancer cells through activating cortactin. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 261. doi:10.1158/1538-7445.AM2013-261
Abstract 2626: Characterization of the invading cells in glioblastoma using a syngeneic intracranial transplant tumor model.
Authors: Zhang Nailing , Song Yurong , Jansen Sanaz , Adhikari Amit , Wang Sophie , Lu Lucy , Sullivan Teresa , Van Dyke Terry
Published: August 2014

Local and distant invasion is a hallmark property of glioblastoma (GBM) that prevents curative surgical resection, and may be the key reason for GBM recurrence. Although cancer stem cells (CSCs) have been suggested to cause tumor recurrence based on their resistance to radiotherapy and chemotherapy, it is not clear whether CSCs are also involved in GBM invasiveness. We hypothesize that the invading cells in GBM have stem-like properties. To test our hypothesis, we propose to characterize cells at the invasive front of GBM using a syngeneic intracranial transplant tumor model.

Three core regulatory networks are dysregulated in most human GBMs, including the RTK/RAS/PI3K/PTEN, INK/Cyclin D/CDK/RB, and ARF/p53 pathways. We have previously generated a genetically engineered mouse (GEM) model for GBM development via adult-inducible astrocyte-specific perturbation of RB, K-RAS and PTEN. These mice develop astrocytomas that progress to high grade GBM, and faithfully recapitulate the histopathology and molecular characteristics of most human GBMs. We have isolated primary tumor cells from these mice that are maintained in serum-free neural stem cell culture medium and expanded as neurospheres. These primary and low-passage cultures contain a mixed population of cancer stem cells and progenitor cells, and are highly invasive in vitro by matrigel invasion assay. With > 90% penetrance, intracranial injection of 25,000 cells leads to invasive GBM formation and a 32-day median survival in syngeneic host mice. Thus, the model provides an efficient approach for dissecting GBM cell invasion mechanisms in vivo. We will further trace the migration/invasion of GBM cells in the host brain after labeling with lentiviral-expressed mCherry. Host blood vessels are labeled with YFP via Tie2-Cre endothelial expression of a Rosa26-YFP allele. A time course analysis of stem cell marker expression will be used to assess properties of invading cells at the diffusive tumor margin. Laser capture microdissection will be used for invasive rim-cell and non-invasive core-cell isolation, and RNA samples will be compared by unbiased transcriptome studies. Results will provide hypotheses for invasion mechanisms and may identify potential biomarkers for invasive cells.

Citation Format: Nailing Zhang, Yurong Song, Sanaz Jansen, Amit Adhikari, Sophie Wang, Lucy Lu, Teresa Sullivan, Terry Van Dyke. Characterization of the invading cells in glioblastoma using a syngeneic intracranial transplant tumor model. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2626. doi:10.1158/1538-7445.AM2013-2626
Abstract 264: Mesenchymal stem cells mediate epithelial-to-mesenchymal transition (EMT) and stemness regulation in pancreatic cancer via Notch signal.
Authors: Kabashima-Niibe Ayano , Higuchi Hajime , Matsuzaki Yumi , Mabuchi Yo , Funakoshi Shinsuke , Adachi Masayuki , Hamamoto Yasuo , Takaishi Hiromasa , Hibi Toshifumi
Published: August 2014

Cancer associate fibroblasts (CAFs), one of the major components of the cancer stroma, are prominently involved in tumor progression including epithelial to mesenchymal transition (EMT). Recently, bone marrow derived mesenchymal stem cells (MSCs) have been suggested as candidate for the source of tumor-promoting CAFs. We previously demonstrated that side population (SP) cells, which are enriched with so-called tumor initiating stem cell like cells (TISCs), play a pivotal role of local invasion and liver metastasis in pancreatic cancer (Int-J-Cancer 124:2771, 2009). Therefore, we formulated the hypothesis that MSCs regulate SP cells EMT and TISC-like properties such as tumor formation/progression. The AIM of the present study was to examine whether bone marrow-derived MSCs have ability to mediate EMT and/or tumor progression in pancreatic cancer SP cells. METHODS: MSCs were pre-treated with TGF-beta for 3 days. SP or non-SP cells were co-cultured in the presence or absence of TGF-beta-pretreated MSCs (Tb-MSCs) for 3 days. Real-time PCR experiments were performed to quantitate mRNA levels of EMT associated genes as well as so-called stemness related genes. PANC-1 derived SP or non-SP cells were co-injected with Tb-MSCs into NOD/SCID mice, and their tumorigenesity was evaluated. RESULTS: Co-culturing with Tb-MSCs dramatically induced EMT-associated mRNA alterations including suppression of E-cadherin and induction of slug in PANC-1 SP cells. In SP cells but not in non-SP cells, levels of stemness genes including CD133, Oct4, LGR5, were enhanced by co-culturing with Tb-MSCs. Tb-MSCs enhanced in vitro sphere forming activity as well as in vivo tumor formation in SP cells. These alterations including EMT-associated gene modifications and enhanced sphere formation were suppressed by Notch signal inhibition, suggested MSCs-associated regulation of EMT and TISC-like properties are mediated by Notch-signaling. In CONCLUSION, MSCs regulate EMT and they maintain TISC-like properties in pancreatic cancer SP cells via Notch signal-dependent mechanisms. Targeting Notch signaling would appear to be attractive to prevent MSCs and/or stromal cell-associated cancer progression.

Citation Format: Ayano Kabashima-Niibe, Hajime Higuchi, Yumi Matsuzaki, Yo Mabuchi, Shinsuke Funakoshi, Masayuki Adachi, Yasuo Hamamoto, Hiromasa Takaishi, Toshifumi Hibi. Mesenchymal stem cells mediate epithelial-to-mesenchymal transition (EMT) and stemness regulation in pancreatic cancer via Notch signal. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 264. doi:10.1158/1538-7445.AM2013-264
Abstract 2657: The role of NR5A2 in pancreas development and oncogenesis.
Authors: Nissim Sahar , Wucherpfennig Julia , Wang Xiao-Xu , Kimmelman Alec , Goessling Wolfram
Published: August 2014

Pancreatic ductal adenocarcinoma (PDAC) remains one of the most lethal cancers today. A recent genome-wide association study (GWAS) has implicated the nuclear receptor NR5A2 in modulating risk for pancreatic cancer. While a role for this gene in pancreatic cancer has not been previously recognized, it is known to have an important role in stem cell pluripotency and metabolism. Using the zebrafish model organism, we demonstrate that knockdown of nr5a2 results in absence of exocrine pancreas, while leaving endocrine pancreas unaffected, indicating an essential role in pancreas organ formation. Further, we localize expression of nr5a2 to the endodermal bud that gives rise to the exocrine pancreas, consistent with a role for nr5a2 in regulating differentiation of pancreas progenitors. In resected human PDAC specimens and in vitro cell lines, we find that NR5A2 is overexpressed compared to normal ductal epithelium. Moreover, shRNA knockdown of NR5A2 dramatically slows proliferation of PDAC cell lines, supporting the hypothesis that NR5A2 is involved in pancreatic carcinogenesis. These data support a model that NR5A2 regulates the proliferation and differentiation of exocrine pancreas progenitor cells during development. We postulate that aberrant expression of NR5A2 results in dysregulation of these processes in the adult pancreas by driving ductal epithelial cells to acquire properties of progenitor cells, and therefore may be an important step in pancreas oncogenesis.

Citation Format: Sahar Nissim, Julia Wucherpfennig, Xiao-Xu Wang, Alec Kimmelman, Wolfram Goessling. The role of NR5A2 in pancreas development and oncogenesis. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2657. doi:10.1158/1538-7445.AM2013-2657

Note: This abstract was not presented at the AACR Annual Meeting 2013 because the presenter was unable to attend.
Abstract 2662: Effects of chemotherapy on tumor hypoxia measured with 18-F-FAZA PET/CT and compared to FDG-PET/CT in advanced non-small-cell lung cancer (NSCLC).
Authors: Kerner Gerald S.M.A. , Bollineni Vikram R. , Hiltermann Thijo J.N. , Pruim Jan , Groen Harry J.M.
Published: August 2014

Introduction

Hypoxia in tumors is associated with resistance to chemotherapy. 18-F-FAZA is a PET tracer developed to characterize intratumoral hypoxic regions. Tumor metabolism is measured with 18-F-FDG PET. Goal of this study is to investigate hypoxic changes in relation to metabolic alterations in patients with advanced NSCLC during chemotherapy.

Methods

PET-CT with 18-F-FDG and 18-F-FAZA tracers were used prior to the first cycle and after the second cycle of chemotherapy. Volumes of interest were manually drawn on visual inspection. For FAZA, mean and maximum (max) tumor to background (FAZAT/B) ratios, and for FDG, SUVmax and SUVmean, were calculated. Measurements were corrected for partial volume using a NEMA image quality phantom. The fractional hypoxic volume, defined as the tumor fraction with a T/B ratio above 1.2 was calculated. The hypoxic and metabolic distribution within the primary tumor was studied with skewness and kurtosis. Differences between baseline and second measurement were calculated with the Wilcoxon signed rank test.

Results

FDG and FAZA scans were performed in 9 patients. Median FAZAT/Bmax was 2.8 (1.9-4.7) at baseline and 3.3 (1.3-5.5) and after 2 cycles, respectively, while SUVmax was 14.8 (5.8-32.5) at baseline and 14.6 (1.9-24.9) after 2 cycles. Fractional hypoxic volume was 78% (17-100%) at baseline and 74% (0-100%) after 2 cycles of therapy. No significant changes in hypoxia or metabolism were observed during chemotherapy. Hypoxic and metabolic heterogeneity within the primary tumor remained unchanged. At baseline skewness was different between FDG and FAZA (p=0.02). After 2 cycles this difference did not persist (p=0.31). There was no difference at baseline or after 2 cycles in kurtosis between FDG and FAZA. Tumor response measured with CT was 2 PR, 5 SD and 2 PD.

Conclusion

In this exploratory study the fractional hypoxic volume and the heterogeneity of hypoxic and metabolic areas remained unchanged during chemotherapy. The intratumoral difference in FAZA and FDG distribution changed from baseline to that after 2 cycles of chemotherapy.

Citation Format: Gerald S.M.A. Kerner, Vikram R. Bollineni, Thijo J.N. Hiltermann, Jan Pruim, Harry J.M. Groen. Effects of chemotherapy on tumor hypoxia measured with 18-F-FAZA PET/CT and compared to FDG-PET/CT in advanced non-small-cell lung cancer (NSCLC). [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2662. doi:10.1158/1538-7445.AM2013-2662
Abstract 2691: Chemokine expression profile in prostate cancer cell lines: Association with metastatic potential.
Authors: Reyes Niradiz , Bettin Alfonso , Rebollo Juan , Correa Oscar , Geliebter Jan
Published: August 2014

Background: Metastatic spread poses the greatest challenge for the management of Prostate Cancer (PCa). Although its frequency at diagnosis of PCa cases is only 4%, it is associated with poor prognosis, with five year survival rates of only 30%. Molecular mechanisms involved in metastatic progression are not completely understood; however, it has been noted that chemokines and their receptors play a key role in the establishment of metastatic lesions.

Objective: To compare the mRNA expression profiles of chemokines and their receptors in two human PCa cell lines with different metastatic phenotypes (LNCaP, PC-3) and in a control, normal prostate epithelial cell line (PWR-1E).

Methods: We evaluated the expression profiles at the transcript level of chemokines and their receptors in LNCaP, PC-3 and PWR-1E human cell lines using a commercial primer panel (Chemokines SensiMix qPCR Primers Panel©,Origene Technologies), as well as a custom primer panel. The relative quantification of gene expression was determined using the ΔΔCt method with the normal PWR-1E cell line as the reference cell line and normalizing the expression to β-actin, HPRT1 and GAPDH housekeeping genes.

Results: Sixteen gene transcripts were overexpressed in PC-3, 13 of which were exclusively overexpressed in this cell line and 3 other genes were up-regulated in both PC-3 and LNCaP cell lines. Of the 13 genes overexpressed in PC-3, 12 were found under-expressed in LNCaP cell line, compared to PWR-1E (CCL2, CCL26, CCL28, CXCL2, CXCL3, CXCL4, CXCL4V1, CXCL6, IL8, CXCL12, CCR10, and CCRL2). Chemokine transcript under-expression was more frequently found in LNCaP than in PC-3 (11 vs 8) and transcripts for genes CCL3, CCL3L1, CCL3L3, CCL27 and DARC were underexpressed in both cell lines.

Discussion: Here we describe the differential chemokine expression profile between PCa cell lines with different metastatic potentials. In addition to chemokines/receptors known to play a role in PCa, we have identified the differential expression of chemokine gene transcripts not previously associated with PCa.

Conclusions: Differential chemokine expression at the mRNA level was found in association with metastatic phenotypes of PCa cell lines. Additional research is needed to determine mechanisms involved in genic regulation of this profiles and to determine their roles in tumorigenesis and cancer progression in the prostate.

Financial support: Colciencias Contract #462-2008

Citation Format: Niradiz Reyes, Alfonso Bettin, Juan Rebollo, Oscar Correa, Jan Geliebter. Chemokine expression profile in prostate cancer cell lines: Association with metastatic potential. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2691. doi:10.1158/1538-7445.AM2013-2691
Abstract 2698: Alternative expression of E2F1, EZH2 and SUZ12 response for the invasive progression of superficial bladder cancers.
Authors: Lee Se-Ra , Roh Yun-Gil , Chu In-Sun , Yeom Young Il , Leem Sun-Hee
Published: August 2014

A superficial bladder cancer is a noninvasive cancer that is presented as a good prognosis after receiving treatment, and noninvasive. However, about 20∼50% of superficial bladder cancer patients progressed to invasive tumor which represent the poor survival rates within 5 years. In previous study, we addressed if the transcriptional characteristics of the superficial bladder cancer could be used as predictive biomarkers for the progression of superficial tumors to invasive ones. Using gene expression data from 165 bladder cancer patients, we identified a gene expression signature that could predict the likelihood of progression to invasive tumors. Gene network analyses of the signature revealed that E2F1 and its downstream effectors EZH2 and SUZ12 could be important mediators for the invasive and metastatic progression of superficial tumors. In this study, we investigated how these genes may affect the invasive and metastatic progression of superficial tumors. We investigated the invasive ability by these genes in two groups of bladder cancer cell lines: One group (UC5 and UC9) has a superficial signature of bladder cancer, and the other group (EJ and 5637) has an invasive signature of bladder cancer. We examined the effects of overexpression or siRNA inhibition of these genes on cell growth, migration and invasion in bladder cancer cell lines. We will report the results estimating the roles of these genes for the invasive and metastatic progression in bladder cancer cell lines.

Citation Format: Se-Ra Lee, Yun-Gil Roh, In-Sun Chu, Young Il Yeom, Sun-Hee Leem. Alternative expression of E2F1, EZH2 and SUZ12 response for the invasive progression of superficial bladder cancers. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2698. doi:10.1158/1538-7445.AM2013-2698
Abstract 270: Cell assay on a chip to study tumor initiating cells’ heterogeneity and treatment resistance.
Authors: Zhang Weijia , Qin Lidong
Published: August 2014

Recent investigations from both animal models and clinical samples have continuously supported that Tumor Initiating Cell (TIC) does exist and plays an important role in tumor metastasis and recurrence. However, TICs have a few intrinsic properties leading to their complexity in molecular targeting and inhibition. TICs are 1) heterogeneous, 2) dynamically changing states, 3) often rare and 4) lack robust biomarker combinations, thereby challenging conventional bulk in vitro experimental tools and complicating the prediction and explanation of animal study results. High throughput, in situ, and cell-by-cell measurement on TICs is a way to fully decipher TIC's molecular signature and signaling pathways. We believe such measurement can lead to 1) revolutionary implementation of TIC models; 2) identification of new therapeutic targets; and 3) reduction of breast cancer recurrence and metastasis. Microfluidics technology (1) is a candidate to serve as such type of high throughput single-cell characterization.

We started pursuing such measurements a few years ago and demonstrated high throughput single-cell protein profiling on both cell lines and clinical samples. The technology, called single-cell barcode chip (SCBC), is facilitated by state-of-the-art Polydimethylsiloxane (PDMS) microfluidics protocols. The SCBC consists of down to nanoliter chambers that concentrate proteins from individual cells to a level even higher than cell culture media in conventional dish technology and contains extremely miniaturized antibody arrays to capture proteins produced by cells in these chambers. Further utilization of our SCBC platform to TICs is expected to characterize protein expression from individual breast TIC and lead to new discoveries in TIC filed.

Citation Format: Weijia Zhang, Lidong Qin. Cell assay on a chip to study tumor initiating cells’ heterogeneity and treatment resistance. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 270. doi:10.1158/1538-7445.AM2013-270
Abstract 2703: A direct regulation of Twist1 by FOXQ1 promotes colorectal cancer metastasis.
Authors: Abba Mohammed , Patil Nitin , Rasheed Kabeer , Nelson Laura D. , Mudduluru Giridhar , Leupold Jörg H. , Allgayer Heike
Published: August 2014

Abstract

Malignant cell transformation, invasion and metastasis are dependent on the coordinated rewiring of gene expression. A major component in the scaffold of these reprogramming events is one in which epithelial cells lose intercellular connections and polarity and adopt a motile mesenchymal phenotype, one that is largely supported by a robust transcriptional machinery consisting mostly of developmental transcription factors.

We investigated the winged helix transcription factor, FOXQ1, identified from an oligonucleotide microarray expression analysis, as being concomitantly deregulated in both epithelial and stromal compartments. We found that FOXQ1 contributes to epithelial to mesenchymal transition (EMT), in part by directly affecting the transcription of Twist1, itself a key mediator of metastasis that transcriptionally regulates the expression of important molecules involved in EMT. Reporter gene assays and chromatin immunoprecipitation experiments showed that FOXQ1 regulated and directly interacted with the Twist1 promoter, leading to a suppression of E-cadherin and increased expression of mesenchymal markers. Forced expression and RNAi mediated silencing of FOXQ1 led to increased and decreased levels of Twist1 mRNA and protein levels, respectively, with concomitant effects on migration, invasion and in vivo metastasis of colorectal cancer cells. Moreover, FOXQ1 mRNA and protein expression correlated in a series of resected patient samples. Conclusively our results show that FOXQ1 is a novel mediator of colorectal cancer metastasis and joins the network of transcription factors that orchestrate EMT.

Citation Format: Mohammed Abba, Nitin Patil, Kabeer Rasheed, Laura D. Nelson, Giridhar Mudduluru, Jörg H. Leupold, Heike Allgayer. A direct regulation of Twist1 by FOXQ1 promotes colorectal cancer metastasis. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2703. doi:10.1158/1538-7445.AM2013-2703
Abstract 2711: BART9, an EBV encoded miRNA, regulates E-cadherin and metastasis.
Authors: Chung Yuan Hsu
Published: August 2014

EBV is a casual agent of NPC and products of EBV genome are believed to be involved in the pathogenesis of NPC. EBV is the first human virus found to express microRNAs (miRNAs). EBV has been found encoded more than forty miRNAs, the functions of which remain largely unknown. In this study, We discovered that BART9 was expressed at high levels in NPC tissues examined. In addition, the level of BART9 was higher than the best documented human oncogenic miR-21. Next, we investigated the role and mechanism of BART9 in NPC cells, and found that exogenous expression of BART9 enhanced the migration and invasion but not proliferation of EBV negative-NPC cells in vitro. Further, depletion of endogenous BART9 suppressed migration and invasion of EBV-positive NPC cells. We further demonstrated that BART9 directly targeted CDH1-3’-UTR and repressed the expression of CDH1, a metastasis suppressor. In addition, restoring of BART9-resistant CDH1 expression in BART9 over-expression cells recovered the migratory and invasive ability of BART9. More importantly, ectopic expression of BART9 triggered spontaneous metastasis of NPC cells in vivo. Finally, in situ hybridization for BART9 showed strong positive staining in paraffin-embedded nasopharyngeal carcinoma tissues and the CDH1 protein levels have an inverse correlation with BART9 expression. Collectively, our findings indicate that BART9 promoted migration, invasion and metastasis in NPC. It is the first case reported that EBV encodes an BART miRNA has effect on motility of infected cells, suggesting a novel mechanism by which Epstein-Barr virus induces the metastasis and recurrence of NPC.

Citation Format: Hsu Chung Yuan. BART9, an EBV encoded miRNA, regulates E-cadherin and metastasis. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2711. doi:10.1158/1538-7445.AM2013-2711
Abstract 2725: Establishment of the primary human tumor xenograft (tumorgraft) mouse model of pancreatic ductal adenocarcinoma.
Authors: Garcia Patrick L. , Gamblin Tracy , Council Leona N. , Christein John D. , Heslin Martin J. , Richardson Joseph , Yoon Karina J.
Published: August 2014

Pancreatic ductal adenocarcinoma (PDAC), the most common form of pancreatic cancer continues to be plagued by a low overall 5 year survival rate, which has remained at a stagnant 5% over the past 30 years. In addition, pancreatic cancer is the 10th leading diagnosed cancer, yet is the 4th leading cause of cancer related deaths in the US, in both men and women. Recent research efforts have been focused on increasing our understanding of the molecular and genetic aspects of pancreatic cancer, in order to improve outcome for these patients. A major tool of pancreatic cancer research has been the use of established cancer cell lines, although the inherent ability of these cell lines to recapitulate human pancreatic disease is not ideal, due to growth in artificial environment and homogenous nature. Implantation of primary human tumor samples into immune compromised mice have been shown to be more genetically heterogeneous, and allow for more relevant genetic profiling data when compared to established cell lines. To better understand the molecular and genetic events in pancreatic cancer, we established a patient derived primary human tumor xenograft (tumorgraft) model system. Briefly, non-diagnostic tumor tissue was procured from previously consented patients at the University of Alabama at Birmingham Hospital, under IRB approved protocols. The tumors were then examined grossly by a pathologist, and immediately implanted into the flank of immune compromised mice. Here we report, a set of 10 PDAC tumors, with a mean age of patients at diagnosis of 68.3 (± 11.6) years. Primarily, these tumors were stage II (six IIA and four IIB) and with a histological grade reported as five moderately differentiated and five poorly differentiated. Lymph node involvement at the time of surgical resection was also assessed and six patients were positive, while four patients were negative. The tumorgrafts retained the morphological and histological characteristics of the primary tumor, even after serial passage in mice, as determined by a pathologist blinded to tumor identity. Currently, we are using next generation sequencing to generate detailed gene expression, epigenetic, and genotyping profiles of these established PDAC tumors. This work is supported by UAB/UMN SPORE in Pancreatic Cancer-Career Development Award and the Department of Pharmacology/Toxicology, UAB.

Citation Format: Patrick L. Garcia, Tracy Gamblin, Leona N. Council, John D. Christein, Martin J. Heslin, Joseph Richardson, Karina J. Yoon. Establishment of the primary human tumor xenograft (tumorgraft) mouse model of pancreatic ductal adenocarcinoma. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2725. doi:10.1158/1538-7445.AM2013-2725