bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 5184: Distinct mutational patterns in liver fluke-related and non-infection-related bile duct cancers revealed by whole exome sequencing
Authors: Ong Choon Kiat , Chan-on Waraporn , Nairismagi Maarja-Liisa , Lim Weng Khong , Dima Simona , Pairojkul Chawalit , Sithithaworn Paiboon , Popescu Irinel , Rozen Steve , Tan Patrick , Teh Bin Tean
Published: May 2015

Cholangiocarcinoma, the second most common liver cancer, is known to be caused by different etiologies such as liver fluke infection, choledochal cyst and primary sclerosing cholangitis. Thus, this cancer provides a good model to study the impact of different carcinogenic exposures on the specific patterns of somatic mutations in human tumors. To address this issue, we profiled 209 cholangiocarcinomas (CCAs) from Asia and Europe, including 108 cases caused by liver fluke Opisthorchis viverrini (O. viverrini)-infection and 101 cases due to non-O. viverrini etiologies. Whole-exome (N = 15) and prevalence screening (N = 194) revealed recurrent somatic mutations in BAP1 and ARID1A, neither of which has been previously reported to be mutated in CCA. Comparisons between intrahepatic O. viverrini and non-O. viverrini CCAs demonstrated statistically significant different mutation patterns: BAP1 and IDH1/2 were more frequently mutated in non-O. viverrini CCAs, while TP53 displayed the reciprocal pattern. Functional studies demonstrated tumor suppressive roles of BAP1 and ARID1A, establishing the role of chromatin modulators in CCA pathogenesis. These findings indicate that different causative etiologies may induce distinct somatic alterations even within the same tumor type.

Citation Format: Choon Kiat Ong, Waraporn Chan-on, Maarja-Liisa Nairismagi, Weng Khong Lim, Simona Dima, Chawalit Pairojkul, Paiboon Sithithaworn, Irinel Popescu, Steve Rozen, Patrick Tan, Bin Tean Teh. Distinct mutational patterns in liver fluke-related and non-infection-related bile duct cancers revealed by whole exome sequencing. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5184. doi:10.1158/1538-7445.AM2014-5184
Abstract 519: MicroRNA-31 is upregulated by EGF through C/EBPβ signaling cascade in HNSCC
Authors: Lu Wen Cheng , Lin Shu Chun , Chang Kuo Wei , Tu Hsi Feng
Published: May 2015

MicroRNA-31 (miR-31) was reported as an important oncomir in head and neck squamous cell carcinoma (HNSCC) by targeting FIH gene and activating the hypoxia pathway. Epidermal growth factor receptor (EGFR) was also found up-regulated in 80% of HNSCC. The interplay between miR-31 expression and EGFR signaling in HNSCC attract our attention and is worthy elucidating. In this study, we identified the up-regulation of miR-31, miR-181b and miR-222 in OSCC cells following EGF treatment and subsequent analysis showed that EGF treatment up-regulated miR-31 via the AKT signaling pathway and this phenomenon could be counteracted by curcumin, a natural compound with anti-neoplastic activity. EGF treatment and associated AKT activation up-regulated C/EBPβ expression, which was also attenuated by curcumin. Expression of miR-31 could be up-regulated by exogenous C/EBPβ and this was correlated with decreased FIH expression. Moreover, the up-regulation of miR-31 induced by EGF was abrogated by knockdown of C/EBPβ expression. In human HNSCC tissues the significant correlation between expressions of EGFR, C/EBPβ and miR-31 was also detected. This study demonstrated a novel scenario that the up-regulation of miR-31 in HNSCC could be a consequence of EGFR activation, which are mediated by both AKT and C/EBPβ signaling.

Citation Format: Wen Cheng Lu, Shu Chun Lin, Kuo Wei Chang, Hsi Feng Tu. MicroRNA-31 is upregulated by EGF through C/EBPβ signaling cascade in HNSCC. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 519. doi:10.1158/1538-7445.AM2014-519
Abstract 5190: Detection of radioresistant gene of esophageal cancer by the new cyclopedic gene analysis with transposon
Authors: Takesue Tomoko
Published: May 2015

Backgound Radiation is one of the most important therapies same as operation and chemotherapy for esophageal cancer. However a rate of therapeutic effect is low, 68.3% as a chemoradiation therapy for advanced esophageal cancer in Japan. Predicting an effect before radiation therapy is impossible, many patients suffer from side effect of radiation without enough therapeutic effect. To predict and improve an effect, it is need to identify genes and mechanism of radioresistance. Aim of this research is to detect radioresistant gene of esophageal cancer by the new cyclopedic gene analysis with transposon.

Methods Transposon is a base sequence which transports to other location in the genome at random. Inserting CMV promotor to transposon as a transcriptional activator, the following gene of transported transposon is overexpressed and the gene inserted transposon is knocked down. We can get various cells which have a different overexpressed or knocked down gene by transposon method. After drug treatment or irradiation for cells inserted transposon and CMV promotor, named transposon tagged cells, survived cells have overexpressed redioresistant genes or knocked down radiosensitive genes. We can pick up candidate redioresistant genes to detect the location of transposon in survived cells. We have already succeeded to acquire candidate chemoresistant genes of breast cancer and esophageal cancer.

Results Twenty days after irradiation of 9 to 11 Gy for transposon tagged cells, survived cells became colonies. Picking up survived colonies and analyzing its gene, nine genes were detected as a candidate gene. All genes were knocked down by inserting the transposon. Knock down of candidate genes were demonstrated by decreasing an amount of mRNA in survived colonies. Cells of survived colonies also showed higher survival rate after irradiation than the rate of parent esophageal cancer cells without transposon. These results mean that knocking down of the candidate gene relates to redioresistance actually. Cytochrome c oxidase subunit 1 is one of the gene detected by transposon method. Cytochrome c oxidase 1 is known as an enzyme of Cytochrome c which induce apoptosis after DNA damage from radiation by activating caspase cascade. This fact supports that knock down of cytochrome c oxidase 1 may suppress release of cytochrome c and then radiation induced apoptosis.

Conclusion Transposon method is able to analyze resistant genes comprehensively. To reveal resistant mechanism of detected gene, new target of treatment may be found.

Citation Format: Tomoko Takesue. Detection of radioresistant gene of esophageal cancer by the new cyclopedic gene analysis with transposon. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5190. doi:10.1158/1538-7445.AM2014-5190
Abstract 5197: MiR-629 targets TRIM33 to promote TGF-β/Smad signaling in clear cell renal cell carcinoma
Authors: Jingushi Kentaro , Nakata Wataru , Ueda Yuko , Kitae Kaori , Fujita Kazutoshi , Uemura Motohide , Nonomura Norio , Tsujikawa Kazutake
Published: May 2015

Renal cell carcinoma (RCC) is the most common neoplasm of the adult kidney, and clear cell RCC (ccRCC) represents the most common renal histology. To identify a novel biomarker or a candidate target of molecular-targeted drug for ccRCC, we focused on miRNA expression signatures obtained from ccRCC clinical specimens by miRNA-microarray. The expression signatures revealed that miR-629 was significantly up-regulated in ccRCC specimens compared to normal specimens. Inhibition of miR-629 through a hairpin miRNA inhibitor inhibited cell migration and invasion. We found that miR-629 directly targets the Tripartite motif-containing 33 (TRIM33) an inhibitor of TGF-β/Smad signaling pathway. Inhibition of miR-629 significantly suppressed TGF-β -induced Smad activation through up-regulation of TRIM33 expression and subsequent inhibition of Smad2/3 and Smad4 binding. Furthermore, miR-629 inhibition attenuated the effect of TGF-β on expression of EMT-related factors and cell migration and invasion. Finally, in human clinical specimens, TRIM33 was down-regulated where an association with pathological stage and grade. Our findings identify miR-629 as a potent regulator of TGF-β/Smad signaling pathway and functions as an oncomir, which may provide a novel therapeutic strategy for treatment of ccRCC.

Citation Format: Kentaro Jingushi, Wataru Nakata, Yuko Ueda, Kaori Kitae, Kazutoshi Fujita, Motohide Uemura, Norio Nonomura, Kazutake Tsujikawa. MiR-629 targets TRIM33 to promote TGF-β/Smad signaling in clear cell renal cell carcinoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5197. doi:10.1158/1538-7445.AM2014-5197
Abstract 5204: MicroRNA-6734 induces p21 gene expression by targeting a complementary p21 promoter sequence and inhibits colon cancer cells
Authors: Kang Moo Rim , Yun Jieun , Oh Soo Jin , Lee Chang Woo , Park Ki Hwan , Kang Jong Soon
Published: May 2015

MicroRNAs (miRNAs) regulate gene expression by binding to the cellular transcript leading to translational repression or degradation of the target mRNA. However, miRNA have also been shown to induce gene expression by targeting promoter in a phenomenon referred to as RNA activation (RNAa). Recently, p21 promoter targeted small activating RNA, dsP21-322, has been shown to inhibit the growth of various cancer cells. The purpose of this study was to investigate the effects of miR-6734, which has a sequence homology with dsP21-322, on p21 gene activation and cell growth inhibition in HCT116 human colon cancer cells. miR-6734 induced p21 gene expression and the induction of p21 was decreased by treatment with miR-6734-5P inhibitor or p21 siRNAs. Furthermore, single transfection of miR-6734 induced p21 gene expression for 12 days which is an interesting feature of RNAa. Knockdown experiments revealed that induction of p21 by miR-6734 required the miRNA maturation protein Ago2 and nuclear transport protein TNRC6A. Functionally, miR-6734 suppressed cellular growth initiated G0/G1 phase arrest and increased the percentage of apoptotic cells by increasing caspase-3/7 activity in dose dependent manner. In addition, miR-6734-mediated cell cycle arrest and apoptosis was significantly suppressed by miR-6734-5P inhibitor, p21 siRNAs, Ago2 siRNAs and TNRC6A siRNA. These results suggest that endogenous miRNA may facilitate RNAa in cancer for specific gene expression and manipulate cancer cell phenotype.

Citation Format: Moo Rim Kang, Jieun Yun, Soo Jin Oh, Chang Woo Lee, Ki Hwan Park, Jong Soon Kang. MicroRNA-6734 induces p21 gene expression by targeting a complementary p21 promoter sequence and inhibits colon cancer cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5204. doi:10.1158/1538-7445.AM2014-5204
Abstract 5206: Mir-134/487b/655 cluster regulates TGF-β-induced epithelial-mesenchymal transition and drug resistance to gefitinib by targeting MAGI2 in lung adenocarcinoma cells
Authors: Seike Masahiro , Kitamura Kazuhiro , Miyanaga Akihiko , Okano Testuya , Noro Rintaro , Gemma Akihiko
Published: May 2015

Epithelial-mesenchymal transition (EMT) has recently been recognized as a key element of cell invasion, migration, metastasis, and drug resistance in several types of cancer, including non-small cell lung cancer (NSCLC). Our aim was to clarify microRNA (miRNA) -related mechanisms underlying EMT followed by acquired resistance to epidermal growth factor receptor tyrosine-kinase inhibitor (EGFR-TKI) in NSCLC. MiRNA expression profiles were examined before and after TGF-β1 exposure in four human adenocarcinoma cell lines with or without EMT. Correlation between expressions of EMT-related miRNAs and resistance to EGFR-TKI gefitinib was evaluated. MiRNA array and quantitative RT-PCR revealed that TGF-β1 significantly induced overexpression of miR-134, miR-487b, and miR-655, which belong to the same cluster located on chromosome 14q32, in lung adenocarcimona cells with EMT. MAGI2, a predicted target of these miRNAs and a scaffold protein required for PTEN, was diminished in A549 cells with EMT after the TGF-β1 stimulation. Overexpression of miR-134 and miR-487b promoted the EMT phenomenon and affected the drug resistance to gefitinib, whereas knockdown of these miRNAs inhibited the EMT process and reversed TGF-β1-induced resistance to gefitinib. Our study demonstrated that the miR-134/487b/655 cluster contributed to the TGF-β1-induced EMT phenomenon and affected the resistance to gefitinib by directly targeting MAGI2, whose suppression subsequently caused loss of PTEN stability in lung cancer cells. The miR-134/miR-487b/miR-655 cluster may be new therapeutic targets in advanced lung adenocarcinoma patients, depending on the EMT phenomenon.

Citation Format: Masahiro Seike, Kazuhiro Kitamura, Akihiko Miyanaga, Testuya Okano, Rintaro Noro, Akihiko Gemma. Mir-134/487b/655 cluster regulates TGF-β-induced epithelial-mesenchymal transition and drug resistance to gefitinib by targeting MAGI2 in lung adenocarcinoma cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5206. doi:10.1158/1538-7445.AM2014-5206
Abstract 5216: Epigenetic characterization and specific targeting of breast cancer stem cells
Authors: Liu Huiping
Published: May 2015

Metastasis causes 90% of the mortality associated with solid tumors, such as breast cancer. However, the molecular mechanisms underlying metastasis remain poorly understood and no effective approaches are available to cure metastasis. The identification of cancer stem cells (CSCs), a subpopulation of cancer cells with stem cell properties, has brought us a new perspective on cancer, including leukemia and solid tumors. CSCs are proposed to mediate cancer relapse and metastasis due to their resistance to conventional therapies. Our work has demonstrated that breast cancer stem cells (BCSCs) are able to mediate spontaneous lung metastases in human-in-mouse xenograft models. We have also identified that miR-30c, a human breast tumour prognostic marker, regulates both invasion and chemo-resistance, through targeting TWF1, VIM, and downstream IL-11. TWF1 encodes an actin-binding protein and promotes epithelial-to-mesenchymal transition (EMT). An IL-6 family member, IL-11 was identified as a secondary target of TWF1 in the miR-30c signalling pathway. Expression of miR-30c inversely correlated with TWF1 and IL-11 levels in primary breast tumors and low IL-11 correlated with relapse-free survival in breast cancer patients. Our study demonstrates that miR-30c is transcriptionally regulated by GATA3 in breast tumors. Identification of a novel miRNA-mediated pathway that regulates chemo-resistance in breast cancer will facilitate the development of novel therapeutic strategies. Future ongoing interactive basic and translational research directions include: (1) to understand CSCs using cutting-edge single cell sequencing technology and functional studies; (2) to image CSCs (their dynamic behavior and interactions with immune cells and non-CSCs) during metastasis using bioluminescence imaging and intravital imaging systems; and (3) to target CSCs with novel therapeutics delivered by nanoparticles.

Citation Format: Huiping Liu. Epigenetic characterization and specific targeting of breast cancer stem cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5216. doi:10.1158/1538-7445.AM2014-5216
Abstract 5222: microRNA-148a is a prognostic oncomiR that targets MIG6 and BIM to regulate EGFR and apoptosis in glioblastoma
Authors: Kim Jungeun , Zhang Ying , Skalski Michael , Hayes Josie , Kefas Benjamin , Schiff David , Purow Benjamin , Parsons Sarah , Lawler Sean , Abounader Roger
Published: May 2015

In this study, we uncovered microRNA-148a (miR-148a) as a novel prognostic and oncogenic microRNA in glioblastoma (GBM). MiR-148a expression was significantly higher in human GBM tissues, cell lines and stem cells (GSCs) as compared to normal human brain and astrocytes. High miR-148a levels were a risk indicator for GBM patient survival. MiR-148a increased GBM cell and GSC growth, survival, migration, and invasion as well as GSC neurosphere formation. We identified the EGFR regulator, MIG6, and the apoptosis regulator, BIM as two direct targets of miR-148a and showed with rescue experiments that they mediate the oncogenic effects of miR-148a. Importantly, by inhibiting MIG6 expression, miR-148a reduced EGFR trafficking to the Rab7-expressing late endosome/lysosomal compartments. This coincided with a reduction of EGFR degradation and induction of EGFR expression and activation. Lastly, inhibition of miR-148a expression led to a strong inhibition of GSC and GBM xenograft growth in vivo. These findings represent the first comprehensive analysis of the role of miR-148a in GBM. They show that miR-148a expression levels are predictive of patient survival and that this microRNA enhances malignancy by inhibiting apoptosis and indirectly activating EGFR. These results also suggest that miR-148a is a potential target for GBM therapy.

Citation Format: Jungeun Kim, Ying Zhang, Michael Skalski, Josie Hayes, Benjamin Kefas, David Schiff, Benjamin Purow, Sarah Parsons, Sean Lawler, Roger Abounader. microRNA-148a is a prognostic oncomiR that targets MIG6 and BIM to regulate EGFR and apoptosis in glioblastoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5222. doi:10.1158/1538-7445.AM2014-5222
Abstract 5228: Characterization of miR-21 as a potential circulating biomarker for osteosarcoma
Authors: Nakka Manjula , Li Yiting , McGee Colin , Lau Ching , Man Tsz Kwong
Published: May 2015

MicroRNAs (miRNAs) are a class of small noncoding RNAs that are implicated in various important biological processes by regulation of gene expression. Aberrant miRNA expression is suggested to be associated with various human disorders including cancer. In this study, we studied if miRNAs can be used as biomarkers in osteosarcoma (OS). OS is the most common malignant bone tumor in children and young adults. Despite the use of surgery and multi-agent chemotherapy, OS patients who respond poorly towards chemotherapy or develop relapses have a dismal outcome. Thus, it is of clinical significance if a biomarker approach can be developed to monitor tumor burden and detect early relapses in the patients, so that they can be treated as early as possible to improve the survival. To achieve this goal, we performed miRNA profiling on a cohort of OS plasma samples collected from the Texas Children's Hospital. miR-21 and other miRNAs were identified to be elevated in OS patients relative to a group of healthy controls. Circulating miR-21 has been detected in other types of cancer and in the tumor it is known to negatively regulate tumor suppressor genes involved in proliferation, apoptosis and invasion; however, its role in OS is still unclear. Hence, we first validated that miR-21 was elevated in a set of independent osteosarcoma plasma samples but not in the control samples. Using serial plasma samples from a group of patients, we found that the circulating miR-21 level was lower in the posttreatment plasma samples than in the pretreatment samples. These results suggest that circulating miR-21 may correlate with tumor burden of the patients. In addition, miR-21 was expressed in many OS tumors as detected by in situ hybridization on an OS tissue microarray. When tested on two OS cell lines, miR-21was significantly increased in the culture media between 24 and 48 hours after plating in a cell number dependent manner, suggesting that miR-21 could be released from the tumor cells. Taken together, our results suggest that miR-21 is expressed in OS and its level in plasma may reflect tumor burden in OS patients.

Citation Format: Manjula Nakka, Yiting Li, Colin McGee, Ching Lau, Tsz Kwong Man. Characterization of miR-21 as a potential circulating biomarker for osteosarcoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5228. doi:10.1158/1538-7445.AM2014-5228
Abstract 523: Detection of PIWI-piRNAS in the mitochondria of human normal and cancer cells
Authors: Kwon ChangHyuk , Tak Hyosun , Rho Mina , Chang Hae Ryung , Km Yon Hui , Kim Kyung Tae , Lee Eun Kyung , Balch Curt , Nam Seungyoon
Published: May 2015

Piwi-interacting RNAs (piRNAs) are a class of small non-coding RNAs that regulate differentiation in primordial germ cells, found mainly in the nucleus and cytoplasm. However, despite the essentiality of mitochondria to intrinsic apoptosis and energy metabolism, the presence of piRNAs (and their associated Piwi proteins) in this organelle remains largely unknown. In this study, a public database comparison of mitochondrial RNA-seq data from human normal (HEK293) and cancer (HeLa and 143B) cells revealed the presence of 29 mature piRNA sequences, with 12 of those piRNA sequences perfectly matching 7 tRNAs (Phe, Val, Leu, His, Ser, Glu, and Thr), suggesting piRNAs and tRNAs derive from a common precursor mitochondrial polycistronic transcript. Consistent with their known interaction with piRNAs, further examination revealed the presence of PIWI proteins in mitochondria. Moreover, the majority of the 29 piRNA sequences overlapped multiple longer sequences (expressed sequence tags, ESTs) that uniquely mapped to the mitochondrial genome. To our knowledge, this is the first report of Piwi and piRNAs in the mitochondria of mammalian normal and cancer cells.

Citation Format: ChangHyuk Kwon, Hyosun Tak, Mina Rho, Hae Ryung Chang, Yon Hui Km, Kyung Tae Kim, Eun Kyung Lee, Curt Balch, Seungyoon Nam. Detection of PIWI-piRNAS in the mitochondria of human normal and cancer cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 523. doi:10.1158/1538-7445.AM2014-523
Abstract 5236: Identification of miR-888 as the first miRNA cancer-testis antigen
Authors: Hovey Adriann M. , Devor Eric J. , Dai Donghai , Leslie Kimberly K.
Published: May 2015

Cancer-testis (CT) antigens are a large family of genes that are exclusively expressed in human testes and are typically located on the X chromosome and part of multicopy gene families. Importantly, CT antigens are overexpressed in a variety of tumors. To date, all known CT antigens are protein-coding genes. Here we identify miR-888 as the first miRNA with features characteristic of a CT antigen. In a panel of 21 normal human tissues, miR-888 expression was high in testes, but minimal or absent in all other tissues. Analysis of cancer cell lines demonstrated expression of miR-888 in endometrial cancer cells, but not in choriocarcinoma, breast, ovarian or prostate cancer cells. In endometrial patient tumor specimens, miR-888 was 8-fold overexpressed relative to benign endometrium (p < 0.01). In addition, expression of miR-888 was highest in endometrial carcinosarcomas (fold change = 22, p < 0.01), a rare and aggressive type of endometrial tumor. Analysis of The Cancer Genome Atlas database revealed that miR-888 expression is significantly associated with high stage and grade endometrial tumors, which has also been observed for many other CT antigens. Furthermore, the miR-888 gene is part of a multicopy gene family on the X chromosome and evolved recently in primates through gene duplication. Therefore, we classify miR-888 as the first miRNA CT antigen and hypothesize that other miRNAs located on the X chromosome may also function as CT antigens. These findings have the potential to advance understanding of cancer-testis genes, their evolution and what role they play in testis and cancer biology.

Note: This abstract was not presented at the meeting.

Citation Format: Adriann M. Hovey, Eric J. Devor, Donghai Dai, Kimberly K. Leslie. Identification of miR-888 as the first miRNA cancer-testis antigen. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5236. doi:10.1158/1538-7445.AM2014-5236
Abstract 5239: MiR-148a promotes apoptosis in urothelial cell carcinoma of the bladder cells in part by targeting DNMT1
Authors: Lombard Alan , Mooso Ben , Libertini Steve , Lim Rebecca , Costanzo Nicole , Ghosh Paramita , Mudryj Maria
Published: May 2015

Introduction: MiRNAs are now recognized as major players in cancer. MiR-148a has been shown to be a tumor suppressor in the context of several cancers including prostate, gastric, and lung but a study investigating its role in bladder cancer has never been performed. Here we characterized the expression and role of miR-148a in bladder cancer.

Methods: Real time PCR was used to assess the levels of miR-148a across several bladder cancer cell lines. MiR-148a mimics were employed in T24 and UM-UC-3 cells to assess proliferation by CCK-8 proliferation assay, colony formation assay, and flow cytometry. Mimics were also used to assess apoptosis by immunoblot and annexin-V staining coupled to flow cytometry. Immunoblot was used to probe for targets of miR-148a and siRNA was used to knock-down DNMT1 to phenocopy miR-148a treatment results. CCK-8 proliferation assays and crystal violet staining were used to assess the additive effects of miR-148a with either cisplatin or doxorubicin on T24 and UM-UC-3 cells and CCK-8 proliferation assays were also used to assess the role DNMT1 plays in cisplatin sensitivity.

Results: All bladder cancer cell lines had significantly reduced expression of miR-148a than that of a control immortalized urothelial cell line. MiR-148a mimic treatment of T24 and UM-UC-3 cells led to large decreases in viability. Flow cytometry demonstrated an increase in S-phase and no major G1 or G2/M arrests in miR-148a mimic treated cells versus control oligo treated cells suggesting that the effects observed on viability were due to increased apoptosis. Immunoblots for cleaved caspase-3 and cleaved PARP along with annexin-V staining coupled to flow cytometry showed as expected a strong induction of apoptosis in miR-148a mimic treated cells. Immunoblots demonstrated that miR-148a targets DNMT1 and DNMT1 knock-down was able to partially phenocopy results from miR-148a mimic treatment suggesting DNMT1 is downstream of miR-148a. Finally, we found that miR-148a can be used with either cisplatin or doxorubicin for an additive effect in inducing apoptosis and that DNMT1 targeting is involved in sensitivity to cisplatin.

Conclusions: Our work demonstrates for the first time that miR-148a plays a tumor suppressive role in bladder cancer and suggests it could be used as a novel therapeutic agent either alone or in conjunction with chemotherapeutics.

Citation Format: Alan Lombard, Ben Mooso, Steve Libertini, Rebecca Lim, Nicole Costanzo, Paramita Ghosh, Maria Mudryj. MiR-148a promotes apoptosis in urothelial cell carcinoma of the bladder cells in part by targeting DNMT1. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5239. doi:10.1158/1538-7445.AM2014-5239
Abstract 5245: A network of microRNAs contolled by oncogenic B-Raf signaling in melanoma cells
Authors: Couts Kasey L. , Anderson Emily M. , Gross Maren M. , Sullivan Kevin , Ahn Natalie G.
Published: May 2015

Constitutive activation of the B-Raf/MKK/ERK signaling pathway a result of B-Raf activating mutations is a hallmark of over two-thirds of melanomas. The most prevalent mutation, B-RafV600E, promotes cancer cell behavior through mechanisms which are still incompletely defined. We utilized microRNA (miRNA) microarray profiling to identify a network of more than 20 miRNAs deregulated by B-Raf/MKK/ERK in melanoma cells, the majority of which modulate expression of key cancer regulatory genes and functions. Importantly, miRNAs within the network converge on protein regulation and cancer phenotypes, suggesting that these miRNAs might function combinatorially. Additionally, by altering functional levels of these miRNAs in cells with miRNA mimics and inhibitors we demonstrate that miRNAs augment effects on protein repression and cell invasion when co-expressed, and we also observe gene-specific latency and interference effects between miRNAs. Thus, B-Raf/MKK/ERK controls key aspects of cancer cell behavior and gene expression by modulating a network of miRNAs with cross-regulatory functions. The findings highlight the potential for complex interactions between coordinately regulated miRNAs within a gene expression network.

Citation Format: Kasey L. Couts, Emily M. Anderson, Maren M. Gross, Kevin Sullivan, Natalie G. Ahn. A network of microRNAs contolled by oncogenic B-Raf signaling in melanoma cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5245. doi:10.1158/1538-7445.AM2014-5245
Abstract 5246: The role of mir-21 and Let-7a in HMGA2 associated colorectal cancer pathogenesis with different APC/k-ras status
Authors: Cheng Ya-Wen , Chen I-Chien
Published: May 2015

Colorectal cancer (CRC) is one of the leading causes of cancer death in both the Western world and Taiwan. Although CRC can be inherited, most CRCs are sporadic. The possible causes of colorectal cancer include a high fat diet, low fiber intake, obesity and sedentary lifestyle. A relatively limited number of oncogenes and tumor-suppressor genes_most prominently the APC, KRAS, and p53 genes are mutated in a sizeable fraction of CRCs. Even though numerous genes have been reported to be associated with tumorigenesis in CRC, only a few of them have been validated and used as biomarkers for predicting metastasis and treatment response in clinical applications. Our published paper showed that overexpression of high-mobility group AT-hook 2 (HMGA2) is associated with metastasis and unequivocally occurred in parallel with reduced survival rates of patients with CRC, and thus HMGA2 may potentially serve as a biomarker for predicting aggressive CRC with poor survivability and as an indicator of better response to radiotherapy. The Let-7a miRNA is a tumor suppressing miRNA that targets oncogenes, including HMGA2. Previous reports show that Let-7a miRNA may regulate miR-21 expression in cholesteatoma. The benign nature of cholesteatoma may be due to a balance between Let-7a and miR-21. The miR-21 has oncogene-like activity and is highly expressed in several types of cancers. Our present study also found that patients with high miR-21 expression had poor survival. In this study, we demonstrated the association of mir-21 and Let-7a in HMGA2 regulation in the pathogenesis of colorectal cancer and how the expression of these genes is associated with the clinical outcomes and radiotherapy response of CRC patients.

Citation Format: Ya-Wen Cheng, I-Chien Chen. The role of mir-21 and Let-7a in HMGA2 associated colorectal cancer pathogenesis with different APC/k-ras status. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5246. doi:10.1158/1538-7445.AM2014-5246
Abstract 5256: Mechanism of field cancerization
Authors: Czerniak Bogdan A. , Lee Sangkyou , Bondaruk Jolanta , Lee Sooyong , Majewski Tadeusz , Zhang Shizhen , Shen Li , Liu Yuexin , Guo Charles , Dinney Colin , Grossman H. Barton , Zhang Wei , Bar-Eli Menashe , Baggerly Keith , Behringer Richard , McConkey David , McConkey David , Knowles Margaret , Chung Woonbok , Issa Jean-Pierre
Published: May 2015

We developed a strategy that combines histologic and genetic mapping that permits interrogation of the chronology of genetic changes associated with cancer development on a whole-organ scale. By using this approach, we analyzed the sequence of genetic alterations contiguous to the tumor suppressor RB1 and identified a set of alternative target genes that we term “forerunner” (FR) genes whose silencing was associated with development of clonal plaque-like mucosal field effects initiating bladder carcinogenesis.

Expression and methylation studies identified five candidate FR genes (ITM2B, LPAR6, MLNR, CAB39L, and ARL11). In vitro mechanistic studies demonstrated that three of these genes (ITM2B, LPAR6 and ARL11) control cell survival and proliferation consistent with their loss of function being contributory to tumorigenesis, and in vivo genetic ablation of Lpar6 in a mouse model resulted in activation of basal/stem cell transcriptional programs involving STAT3 and NFκB causing proliferative expansion of the basal layer of the urothelium. Whole genome analyses of the field effects in a representative whole-organ map revealed a sequential accumulation of alterations in RHO/RAC/Cdc42 pathways that control invasion and cell motility.

These studies identify FR genetic alterations in tissue fields as one of the earliest events in carcinogenesis and provide comprehensive description of field cancerization in a primary human tumor. The results have important implications for the development of novel detection markers and chemoprevention therapeutic strategies.

Citation Format: Bogdan A. Czerniak, Sangkyou Lee, Jolanta Bondaruk, Sooyong Lee, Tadeusz Majewski, Shizhen Zhang, Li Shen, Yuexin Liu, Charles Guo, Colin Dinney, H. Barton Grossman, Wei Zhang, Menashe Bar-Eli, Keith Baggerly, Richard Behringer, David McConkey, David McConkey, Margaret Knowles, Woonbok Chung, Jean-Pierre Issa. Mechanism of field cancerization. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5256. doi:10.1158/1538-7445.AM2014-5256
Abstract 5258: Overexpressed TYRO3 in colorectal cancer regulates tumorigenesis and metastasis
Authors: Chien Chun Wei , Lai Yen-Yu , Lin Bo-Wen , Lin Shao-Chieh , Lee Jenq-Chang , Tsai Shaw-Jenq
Published: May 2015

Colon cancer is a multiple-step disease with less 10% survival rate at late stage. To achieve improvement of colon cancer therapy, we aim to find novel oncogenes that contribute to colon cancer progression. By our in-house bioinformatic tool prediction, we identified TYRO3 to be a potential oncogene. TYRO3, a receptor tyrosine kinase, was reported to be overexpressed in melanoma via genomic screening; however, its role in cancer initiation, progression, and malignancy remains largely unknown. Herein, we showed that compared to normal colon tissue, TYRO3 is overexpressed in polyps and colon cancer tissue. The expression level in colon cancer is significantly associated with cancer malignancy. Overexpression of TYRO3 increased cell proliferation, motility, and anchorage-independent colony formation in vitro. Furthermore, we confirmed TYRO3 tumorigenic potential by xenograft model and metastatic assay in vivo. To investigate novel mechanisms mediated by TYRO3, we performed next generation sequencing (RNS-seq) to identify genes that were upregulated under TYRO3 overexpression. Results showed that TYRO3 significantly enriched genes involved in epithelial-mesenchymal transition and tumorigenesis, which is consistent with our hypothesis and finding. Taken together, these data provide evidence to support that TYRO3 plays an important role in malignant process of colon cancer progression likely through its novel functions in the nucleus.

Citation Format: Chun Wei Chien, Yen-Yu Lai, Bo-Wen Lin, Shao-Chieh Lin, Jenq-Chang Lee, Shaw-Jenq Tsai. Overexpressed TYRO3 in colorectal cancer regulates tumorigenesis and metastasis. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5258. doi:10.1158/1538-7445.AM2014-5258
Abstract 5261: Aberrant expression of HDAC6 sustains malignant progression by preventing epidermal growth factor receptor degradation in gastric cancer
Authors: Park Se Jin , Bae Hyun Jin , Eun Jung Woo , Shen Qinngyu , Kim Hyung Seok , Shin Woo Chan , Park Won Sang , Lee Jung Young , Nam Suk Woo
Published: May 2015

Cytoplasmic deacetylase, histone deacetylase 6 (HDAC6) is a critical component of the lysomal protein degradation pathways. HDAC6 has been shown to be involved in carcinogenic transformation and to modulate the epithelial-mesenchymal transition in several cancers by way of the regulations of several critical cellular functions, but the biological roles in gastric carcinogenesis remains to be elucidated. In this study, we observed that HDAC6 is aberrantly over-expressed in a subset of gastric cancer, and that targeted-inactivation of HDC6 caused cell cycle and cell death pathways-independent growth inhibition. Additional experiments evidenced that ectopic overexpression of HDAC6 sustains epidermal growth factor receptor (EGFR) degradation in EGF-stimulated gastric cancer cells. In addition, we found that HDAC6 inactivation recovered rabaptin 5, a Rab5 interacting protein potentiating Rab5, a small GTPase that regulates early endocytic events. These findings suggest that aberrant overexpression of HDAC6 confers gastric cancer cells to sustain EGF-signaling by retardation of EGFR degradation by way of repression of rababtin-5, and HDAC6 is a bona fide target for therapeutic intervention in gastric cancers.

Note: This abstract was not presented at the meeting.

Citation Format: Se Jin Park, Hyun Jin Bae, Jung Woo Eun, Qinngyu Shen, Hyung Seok Kim, Woo Chan Shin, Won Sang Park, Jung Young Lee, Suk Woo Nam. Aberrant expression of HDAC6 sustains malignant progression by preventing epidermal growth factor receptor degradation in gastric cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5261. doi:10.1158/1538-7445.AM2014-5261
Abstract 5262: Activating transcription factor 4 regulates RET autophosphorylation and ubiquitin-dependent degradation
Authors: Bagheri-Yarmand Rozita , Cote Gilbert J. , Gagel Robert F.
Published: May 2015

RET proto-oncogene, a receptor tyrosine kinase (RTK), activates a complex network of signal transduction pathways that when unregulated contributes to cell transformation. Germ line missense mutations, which give rise to constitutively active oncogenic RET, were found to cause multiple endocrine neoplasia type 2 (MEN2), a dominant inherited cancer syndrome that affects multiple neuroendocrine organs. Recent findings also suggest that impairment of RTK down-regulation or deactivation may be involved in tumorigenesis. The molecular mechanism that functions to attenuate RET signaling remain elusive. ATF4 is a central mediator of integrated stress response pathway. Activation of ATF4 results in tumor cell death under stress conditions thereby suggesting that ATF4 agonists constitute a potential therapeutic strategy for inhibiting tumor growth. Here, we report that ATF4 overexpression in medullary thyroid cancer cells harboring RET C634W mutation decreases RET protein expression but not the mRNA levels. In addition, ATF4 accelerates RET turnover and promotes its ubiquitination. Moreover, a RET kinase dead mutant is more stable than wild type or M918T RET suggesting that kinase activity is required for ATF4-mediated degradation. Finally, ATF4 depletion upregulates RET protein levels and RET autophosphorylation. Our findings unravel ATF4 as a feedback negative attenuator of RET signaling that could be used as a potential therapeutic target for medullary thyroid cancer or other malignancy with RET abnormalities.

Citation Format: Rozita Bagheri-Yarmand, Gilbert J. Cote, Robert F. Gagel. Activating transcription factor 4 regulates RET autophosphorylation and ubiquitin-dependent degradation. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5262. doi:10.1158/1538-7445.AM2014-5262
Abstract 5275: βII-spectrin(SPTBN1) suppresses tumor progression by inhibiting Wnt signaling via kallistatin in hepatocellular carcinoma
Authors: Zhi Xiuling , Lin Ling , Shivapurkar Narayan Shivapurkar , Marshall John L. , Johnson Lynt , He Aiwu R.
Published: May 2015

βII-spectrin(SPTBN1, β2SP), the most common nonerythrocytic member of the β-spectrin gene family, functions as an adapter protein for Smad3/Smad4 complex formation during TGF-β signal transduction, and is required for EMT during embryonic liver development. Moreover, β2SP is emerging as a tumor suppressor. We have reported that Loss of β2SP enhances the stem-like traits and invasiveness of HCC cells. The canonical Wnt pathway, known to be a critical regulator of self-renewal in stem cell, is also constitutively activated and implicated in the induction of EMT in cancer. Kallistatin (a serine protease inhibitor, SERPINA4), which was identified as a unique inhibitor of the Wnt pathway, is expressed primly in the liver. In this study, we investigated the mechanism by which β2SP influences stem cell traits and aggressive behavior of HCC cell lines. We found that cells with decreased β2SP have decreased β-catenin phosphorylation and increased β-catenin nuclear localization, indicative of activation of Wnt signaling. Furthermore, loss of β2SP results in the decease of Kallistatin expression, the Wnt inhibitor. Restore of kallistatin reversed the Wnt activation in HCC cells from decreased β2SP level. Our study provides evidence for the first time that loss of β2SP activates Wnt signal through suppressing kallistatin expression.

Note: This abstract was not presented at the meeting.

Citation Format: Xiuling Zhi, Ling Lin, Narayan Shivapurkar Shivapurkar, John L. Marshall, Lynt Johnson, Aiwu R. He. βII-spectrin(SPTBN1) suppresses tumor progression by inhibiting Wnt signaling via kallistatin in hepatocellular carcinoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5275. doi:10.1158/1538-7445.AM2014-5275
Abstract 5284: SSU72 functions as a gatekeeper monitoring for chromosome integrity in mammals
Authors: Kim Se-Hyuk , Jeon Yoon , Kim Hyun-Soo , Lim Han-Jeong , Lee Ho , Lee Chang-Woo
Published: May 2015

Ssu72 has been initially identified as a protein phosphatase in yeast. It is becoming increasingly clear that Ssu72 plays a major modifier in regulating the transcriptional dynamics through the dephosphorylation (hypophosphorylation) of RNA polymerase II C-terminal domain. Despite these intriguing reports, the physiological function of SSU72 remains unknown particularly in higher eukaryotes. Recently, We have reported that Ssu72 functions as a cohesin-binding phosphatase in regulating sister chromatid cohesion. In addition, we generated the SSU72 conditional knock-out mice, and identified that SSU72 requirement for monitoring hepatic chromosome ploidy and hepatic damage responses in mammals. Furthermore, this study includes the physiology of SSU72 loss-of-function and the novel molecular lesions caused by SSU72 loss in vitro and in vivo.

Citation Format: Se-Hyuk Kim, Yoon Jeon, Hyun-Soo Kim, Han-Jeong Lim, Ho Lee, Chang-Woo Lee. SSU72 functions as a gatekeeper monitoring for chromosome integrity in mammals. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5284. doi:10.1158/1538-7445.AM2014-5284
Abstract 529: nc886, a noncoding RNA of anti-proliferative role, is suppressed by CpG DNA methylation in human gastric cancer
Authors: Park Jong-Lyul , Kim Yong Sung , Kim Seon-Young , Lee Kwang Soo , Jeon Sung H. , Lee Kwanbok , Lee Yong Sun
Published: May 2015

nc886, a novel type of non-coding RNA, was initially identified as a microRNA precursor or a vault RNA, but it has been shown to be distinct from them and rather to be a cellular RNA ligand and inhibitor of PKR (Protein Kinase RNA-activated). PKR's roles in viral infection, cellular stresses, and cancer are well documented. nc886 has also been suggested to be a tumor suppressor, mainly inferred by its expression pattern as well as its genomic location at human chromosome 5q31, a locus for a tumor suppressor gene(s).

Here we have investigated nc886 in gastric cancer where its expression is suppressed due to CpG DNA hypermethylation at its promoter region in a cohort of paired tumor/normal tissues from 88 gastric cancer patients and a battery of gastric cell lines. CpG hypermethylation of nc886 and thus its diminished expression is significantly associated with poor survival in these cancer patients. nc886 inhibits cell proliferation when ectopically expressed in gastric cancer cells. nc886's tumor suppressive role is corroborated by the induction of well-known oncogenes such as FOS, NF-κB, and MYC upon nc886 knockdown. All these activities of nc886 are undoubtedly independent of mature microRNA or vault RNA, but presumably through PKR that is typically activated by viral infection and cellular stresses upon which those oncogenes are known to be induced. Our data indicate that nc886 is a tumor suppressor and could potentially be used as a diagnostic marker and a therapeutic agent in gastric cancer.

Citation Format: Jong-Lyul Park, Yong Sung Kim, Seon-Young Kim, Kwang Soo Lee, Sung Ho Jeon, Kwanbok Lee, Yong Sun Lee. nc886, a noncoding RNA of anti-proliferative role, is suppressed by CpG DNA methylation in human gastric cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 529. doi:10.1158/1538-7445.AM2014-529