bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 2066: Aberrant upregulation of 14-3-3 gamma promotes mononucleated polyploidization in human lung cancers
Authors: Gomes Cecil J. , Harman Michael , Martinez Jesse , Centuori Sara
Published: August 2015

Advanced non-small cell lung cancers (NSCLC), frequently display increased expression of 14-3-3 gamma (14-3-3γ); a scaffolding protein shown to have oncogenic capacity. This aberrant increase in expression has also been correlated with poorer survival, indicating that upregulation of 14-3-3γ results in a more aggressive tumor phenotype. Our lab is in pursuit of characterizing the mechanisms driving this more advanced cancer phenotype. One such mechanism currently being investigated is 14-3-3γ's ability to promote polyploidization in lung cancer cells. Polyploidization is a known mechanism observed to increase tumorigenicity, resistance to conventional therapies, and theorized to promote chromosomal instability. Our data shows that overexpression of 14-3-3γ results in a subpopulation of cells that harbor mono-nucleated tetraploid DNA content. This suggests that elevated expression of 14-3-3γ promotes aberrant cell cycle progression, either by mechanisms of an abortive mitosis known as endomitosis, or by means of endoreplication, a re-replication event occurring in the absence of mitosis. Further analyses have confirmed that these cells, in the absence of tumor suppressor p53, remain viable and undergo cellular division; supporting our hypothesis that upregulation of 14-3-3γ is resulting in an unstable, tumorigenic tetraploid cell state. Taken together, our data elucidates one role by which 14-3-3γ may be contributing to a more aggressive tumor phenotype in patients with advanced NSCLC.

Citation Format: Cecil J. Gomes, Michael Harman, Jesse Martinez, Sara Centuori. Aberrant upregulation of 14-3-3 gamma promotes mononucleated polyploidization in human lung cancers. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2066. doi:10.1158/1538-7445.AM2015-2066
Abstract 207: Caveolin-1 drives oncogenic TGFβ effects in prostate cancer: in vitro mechanistic insights integrated with systems pathology visualization in primary tumor samples
Authors: Pellinen Teijo , Blom Sami , Sanches Sara , Välimäki Katja , Mpindi John-Patrick , Rannikko Antti , Strippoli Raffaele , Montoya Maria , Azegrouz Hind , Mirtti Tuomas , del Pozo Miguel , Kallioniemi Olli
Published: August 2015

Caveolin-1 (Cav1) can have both a tumor suppressive or promoting role depending on cancer tissue, and its potential active role in the progression of prostate cancer remains poorly understood. In this study, we found out that Cav1 represses the expression of E-cadherin in prostate cancer cell lines, and that the expressions of these two genes show an inverse correlation both at the mRNA and protein levels in PCa patient samples. We show that the combined loss of E-cadherin and gain of Cav1 expression is an early event in a subgroup of patients (<10%) (n(patients) = 80, n(glands) = 263, r = -0.35, p<0.001). Cav1 positively regulates TGFβ targets with known oncogenic and pro-EMT functions (e.g. Slug, Pai-1), and its absence switches the TGFβ to become inhibitory to PCa cells by inducing p21 (CDKN1A) and STAT1 signaling. These changes were strongly associated with changes in 3D-invasive growth. By using RNAi image-based screening, we found out that Cav1 is positively regulated by beta1-integrins and cell adhesion to ECM. This association together with different alpha-integrins was visualized and quantified in human prostate cancer patient tissues (n = 80) using novel multiplexed fluorescent imaging. Both the integrin beta1 and alpha2 showed high correlation with Cav1 expression (p-values<0.001) in tumor epithelium as well as in stroma.

In conclusion, the results suggest that Cav1 could be an important promoter of invasive growth in a subgroup of PCa, where it is upregulated by beta1-integrins, and where it promotes oncogenic TGFβ signaling.

Citation Format: Teijo Pellinen, Sami Blom, Sara Sanches, Katja Välimäki, John-Patrick Mpindi, Antti Rannikko, Raffaele Strippoli, Maria Montoya, Hind Azegrouz, Tuomas Mirtti, Miguel del Pozo, Olli Kallioniemi. Caveolin-1 drives oncogenic TGFβ effects in prostate cancer: in vitro mechanistic insights integrated with systems pathology visualization in primary tumor samples. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 207. doi:10.1158/1538-7445.AM2015-207
Abstract 2070: Stxbp4 suppresses APC/C mediated turnover of p63 and increases tumorigenicity and malignancy
Authors: Otaka Yukihiro , Rokudai Susumu , Kaira Kyoichi , Shimizu Kimihiro , Ito Masashi , Ichihara Ami , Kawabata Reika , Yoshiyama Shinji , Yamane Arito , Asao Takayuki , Prives Carol , Nishiyama Masahiko
Published: August 2015

p63 plays a pivotal role in epithelial development and maintenance of epithelial proliferative potential. The delN isoforms of p63 are thought to be involved in both basal-epidermal gene expression and maintenance of epithelial progenitor proliferative potential. It is also thought that delN versions of p63 and p73 can serve to inhibit the abilities of their TA isoform counterparts to induce cell cycle arrest and apoptosis. Consistent with this, after DNA damage or during terminal differentiation, delNp63 proteins are quickly down regulated. Although p53 is frequently mutated in human cancers, p63 mutation is rare and it overexpresses especially in squamous carcinomas, such as lung, bladder, breast, and head and neck squamous cell carcinoma. Indeed several report concluded that immuno histochemistry with delNp63 is a powerful ancillary method for classifying lung adenocarcinoma and squamous carcinoma, a distinction with important therapeutic implications. We previously reported that APC/C plays a role in ubiquitin-mediated turnover of delNp63 and that Stxbp4 suppresses the degradation of delNp63 by the APC/C and Rack1-VHL. Importantly, both Stxbp4 and APC/C degradation-resistant delNp63 suppress the terminal differentiation process in 3D organotypic culture model as well as in vitro culture. To investigate the effect and the mechanism of delNp63 for tumorigenicity and malignancy in Lung squamous carcinoma, we examined a transcriptome analysis (RNA-seq) of delNp63 and Stxbp4 with NGS (Next Generation Sequencer) and generated xenograft mice model. Thus, our study provides insight into a novel mechanism for delNp63 in regulating tumorigenicity and malignancy in squamous cell carcinoma as well as epitherial development.

Citation Format: Yukihiro Otaka, Susumu Rokudai, Kyoichi Kaira, Kimihiro Shimizu, Masashi Ito, Ami Ichihara, Reika Kawabata, Shinji Yoshiyama, Arito Yamane, Takayuki Asao, Carol Prives, Masahiko Nishiyama. Stxbp4 suppresses APC/C mediated turnover of p63 and increases tumorigenicity and malignancy. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2070. doi:10.1158/1538-7445.AM2015-2070
Abstract 2086: Role of the transcription factor NFE2L3 in TNFα signaling pathway in colorectal cancer
Authors: Bury Marina , Blank Volker
Published: August 2015

Patients with inflammatory bowel disease have an increased risk of developing colorectal cancer (CRC), which is the third leading cause of cancer related deaths in the world. Our laboratory is studying the transcription factor NFE2L3 [nuclear factor (erythroid-derived 2)-like 3]. NFE2L3, a member of the Cap’n’Collar family, is a basic-region leucine zipper transcription factor that was identified 15 years ago. Contrary to its extensively studied homolog NFE2L2, the role of NFE2L3 in cancer is still unknown. We demonstrated that NFE2L3 functions as heterodimer by complexing with small Maf (musculoaponeurotic fibrosarcoma) proteins for DNA binding. According to the clinical databases, NFE2L3 is up-regulated in CRC compared to normal tissues. Using the colorimetric MTT viability assay, we determined the optimal concentration to treat colon cell lines with the tumor necrosis factor-alpha (TNFα), a pro-inflammatory cytokine associated with CRC tumorigenesis. We showed that protein levels of NFE2L3 and small Maf proteins are up-regulated by TNFα in CRC cells. We used genomic approaches for identifying genes that are modulated by NFE2L3 after TNFα treatments. The identification of the precise role of NFE2L3 in TNFα signaling pathway will lead to a better understanding of colorectal cancers and will help in the design of novel treatment options.

Citation Format: Marina Bury, Volker Blank. Role of the transcription factor NFE2L3 in TNFα signaling pathway in colorectal cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2086. doi:10.1158/1538-7445.AM2015-2086
Abstract 2119: Identification of a RNA binding protein, SSP1, inducing cell growth in esophageal squamous cell carcinoma (ESCC)through posttranscriptional regulation of target genes
Authors: Imoto Issei , Masuda Kiyoshi , Shoda Katsutoshi , Hamada Jyunichi
Published: August 2015

RNA-binding proteins (RBPs) involve in many post-transcriptional aspects of RNA metabolism. Although the impact of RBPs on expression of cancer-associated genes is well recognized, their crucial functions in carcinogenesis remain unclear. Here we show that a RBP, squamous cell carcinoma-specific protein 1 (SSP1, Lab name), promotes the cell growth in esophageal squamous cell carcinoma (ESCC) through regulating the expression of cell cycle- and apoptosis-associated genes. Immunohistochemical analysis of dissected ESCC samples showed that SSP1 was highly expressed in advanced ESCC compared with normal tissues. Expression levels of SSP1 was positively and significantly correlated with tumor size, invasion depth and overall survival of patients with ESCC. The correlation between SSP1 expression level and overall survival was significant even after stratified with other clinicopathological factors, indicating SSP1 to be an independent prognosticator in ESCC. Knockdown of SSP1 inhibited cell growth and induced G0/G1 arrest in ESCC cell lines, whereas stably overexpressed SSP1 promote cell growth. Ribonucleoprotein immunoprecipitation analysis followed by RNA sequencing (RIP-seq) revealed that SSP1 bound to large sets of mRNAs, including TP53, RB1, CCNA2, CCND1, BAX, and FAS, and regulated their expression through regulation their translation. Our results indicated SSP1 might be one of the crucial molecular targets for ESSC.

Citation Format: Issei Imoto, Kiyoshi Masuda, Katsutoshi Shoda, Jyunichi Hamada. Identification of a RNA binding protein, SSP1, inducing cell growth in esophageal squamous cell carcinoma (ESCC)through posttranscriptional regulation of target genes. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2119. doi:10.1158/1538-7445.AM2015-2119
Abstract 2120: Not all ribosomes are created equal: How cancer abuses the translational machinery
Authors: Landon Ari L. , Muniandy Parameswary , Gartenhaus Ronald B.
Published: August 2015

Translational Dysregulation is emerging as a prominent mechanism leading to the malignant phenotype. These changes in protein levels can lead to cancer initiation, maintenance and progression. Cap-dependent translation is the primary mechanism of mRNA translation in eukaryotic cells. Cap-dependent translation is initiated by eIF4E1 binding to the 7-methyl-guanosine-cap (cap). The conventional translation initiation complex eIF4F consists of eIF4A, eIF4G and eIF4E. eIF4E binds the cap structure in the mRNA functioning as a bridge between mRNA and the ribosome. MNK kinases are responsible for phosphorylating eIF4E1. We observed that knocking down MNK kinases translationally represses total eIF4E1 expression. Interestingly, MNK down regulating total eIF4E1 occurs specifically in B-cells. This novel impact on total eIF4E1 demonstrates the potential for MNK1 and MNK2 to directly impact a large subset of oncogenes in a B-cell specific manner. Inhibiting MNK kinase activity and subsequent eIF4E1 phosphorylation results in an increase in eIF4E3 protein expression. eIF4E3 is another member of the eIF4E family that has been shown to bind the cap by an atypical mechanism. We explored the biological function of eIF4E3 in a diffuse large B-cell lymphoma model. The increase in total eIF4E3 competes with eIF4E1 for binding to the cap. We found that eIF4E3 also physically associates with eIF4A and eIF4G forming a novel eIF4F complex. We interrogated the functional aspects of eIF4E3-mediated translation by analyzing the translatome and transcriptome of eIF4E3 expressing cells. eIF4E3 and eIF4E1 mutually regulate a high fraction of total mRNA transcripts while both family members exclusively modulate translation of select messages. We identified selective motif enrichments in the 5′UTR that may facilitate transcript selection by eIF4E1 or eIF4E3. These findings imply alternative ribosomal complexes that are able to selectively translate mRNA via transcript recognition. The dual roles of MNK proteins for both eIF4E1 phosphorylation and total expression highlight MNK as a powerful oncogenic translation switch.

Citation Format: Ari L. Landon, Parameswary Muniandy, Ronald B. Gartenhaus. Not all ribosomes are created equal: How cancer abuses the translational machinery. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2120. doi:10.1158/1538-7445.AM2015-2120
Abstract 2123: Protein synthesis and its control in cancer development, progression and treatment
Authors: Parsyan Armen
Published: August 2015

A central dogma of molecular biology posits that the protein biosynthetic pathway generally follows the three major events: replication, transcription and translation. The abnormal functioning of any of these processes can nurture malignant cellular transformation. While other components of the central dogma were front-page in cancer research, translation, somewhat, remained in the shades. This presentation is based on the recently published book “Translation and Its Regulation in Cancer Biology and Medicine”* that for the first time comprehensively summarizes and analyzes decades of information into the role of the aberrations in protein synthesis, translation, as well as its regulation in the biology of cancer. The mechanisms of action of various translation factors, such as oncoprotein eIF4E, and tumor suppressors, such as PDCD4, are intensively discussed. Other, less-studied protein factors participating in the complex process of translation are presented in light of their known or emerging roles in cancer development and progression. In addition, the presentation focuses on the oncogenic role of the regulation of the translation machinery by fundamental cellular signal transduction pathways, such as mTOR, MAPK and others. Finally, clinical applications of the current knowledge regarding the translation machinery, its function and regulation in cancer are highlighted, including the use of the translation factors as diagnostic and prognostic markers, as well as factors for novel approaches to targeted pharmacologic treatment.

* Translation and Its Regulation in Cancer Biology and Medicine

Parsyan, Armen (Ed.)

2014, XXXIV, 697 p. 52 illus., 44 illus. in color., Hardcover

ISBN 978-94-017-9078-9

Springer Publishing

Website: http://www.springer.com/biomed/cancer/book/978-94-017-9077-2

Citation Format: Armen Parsyan. Protein synthesis and its control in cancer development, progression and treatment. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2123. doi:10.1158/1538-7445.AM2015-2123
Abstract 2132: Mutant Kras associated protein oxidation in pancreatic neoplasia
Authors: Schultz Michelle , DeCant Brian , Diaz Andrew , Solman Sharon , Shah Rital , Bentrem David , Grippo Paul J.
Published: August 2015

Recent studies have suggested that mutant Kras associated activation of the Nrf2 pathway may have a significant role in pancreatic cancer (PaCa) tumorigenesis. Nrf2 regulates a battery of antioxidant genes, including peroxiredoxin-1 (Prdx-1), thioredoxin (Txn), and sulfiredoxin (Srxn), which are responsible for maintaining redox homeostasis in the cell. While ROS detoxification may have significant roles in cancer, several non-classical mechanisms of redox signaling associated with protein oxidation and phosphorylation are also important in tumorigenesis. Prdx-1 can regulate transcription as a cofactor in multiple oxidation states, represses tumorigenesis in its reduced state, and can act as a nuclear chaperone in elevated states of oxidation and when phosphorylated. Txn and Srxn prevent Prdx-1 overoxidation. We are therefore investigating the role of Prdx-1 oxidation and Txn and Srxn regulation in oncogenic signaling pathways in mutant Kras models of pancreatic tumorigenesis and neoplasia. Our data suggest that throughout tumor progression, Prdx-1 expression and localization are differentially regulated. These changes also correlated with reduced Txn and Srxn expression in lesions. In vitro, neoplastic and tumorigenic pancreatic cell lines have more total prdx-1 expression and oxidized Prdx-1 expression than non-tumorigenic cell lines. Moreover, cells that have mutant Kras were associated with higher levels of protein oxidation than those with wildtype Kras expression. Interestingly, mutant Kras was also associated with differences in pERK interaction with Prdx-1, which was also differentially regulated by NOX inhibitors and omega-3 fatty acids that control pancreatic neoplasia. ERK inhibitors also differentially affected Prdx1 expression in pancreatic cells in vitro. In addition, AKT, ERK, and FOXO3a phosphorylation were also modified by DPI treatment (NOX inhibitor) and omega-3 fatty acid treatment in wildtype and mutant Kras normal, neoplastic, and tumorigenic cell lines. We therefore conclude that mutant Kras is associated with elevated levels of Prdx-1 oxidation and that Kras-mediated activation of ERK could be associated with changes in Prdx-1 signaling in pancreatic neoplasia.

Citation Format: Michelle Schultz, Brian DeCant, Andrew Diaz, Sharon Solman, Rital Shah, David Bentrem, Paul J. Grippo. Mutant Kras associated protein oxidation in pancreatic neoplasia. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2132. doi:10.1158/1538-7445.AM2015-2132
Abstract 2134: Standard immunohistochemistry efficiently screens for ALK rearrangements in differentiated thyroid cancer
Authors: Park Gahee , Kim Tae Hyuk , Lee Hae-Ock , Lim Jung Ah , Won Jae-Kyung , Min Hye Sook , Lee Kyu Eun , Park Do Joon , Park Young Joo , Park Woong-Yang
Published: August 2015

The anaplastic lymphoma kinase (ALK) gene is frequently rearranged in various types of cancer, and is highly responsive to the target therapeutics. We developed a pipeline to detect ALK rearrangement in a large group of Korean thyroid cancer patients. We screened 474 malignant or benign thyroid tumor cases to find ALK fusion. The expression and translocation of the ALK gene were analysed by immunohistochemistry (IHC), fluorescence in situ hybridisation (FISH), and digital multiplexed gene expression (DMGE) using formalin-fixed paraffin embedded tissues. Four cases of ALK rearrangement were screened out of 474 patients by IHC, which were validated by performing FISH for 189 samples. On the other hand, DMGE analysis using Nanostring could detect three out of four IHC positive cases. Two ALK rearrangements were Striatin (STRN)-ALK fusion, identified by 5′ RACE analysis. ALK rearrangements were found exclusively in the BRAF wild type papillary carcinoma. Given the wide availability and accuracy for detecting ectopic ALK expression in the thyroid, we suggest that IHC based screening can be used as a practical method for identifying patients with ALK rearranged differentiated thyroid cancer.

Citation Format: Gahee Park, Tae Hyuk Kim, Hae-Ock Lee, Jung Ah Lim, Jae-Kyung Won, Hye Sook Min, Kyu Eun Lee, Do Joon Park, Young Joo Park, Woong-Yang Park. Standard immunohistochemistry efficiently screens for ALK rearrangements in differentiated thyroid cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2134. doi:10.1158/1538-7445.AM2015-2134
Abstract 2135: Survivin is a novel target of the Hedgehog/GLI signaling pathway in human tumor cell lines
Authors: Vlčková Kateřina , Ondrušová Lubica , Réda Jiri , Vachtenheim Jiri , Záková Petra
Published: August 2015

Survivin, a pivotal antiapoptotic protein is expressed in tumors whereas its expression in normal tissues is extremely low. It is believed that transcription of the survivin gene is driven mainly by the transcription factor Sp1. We have identified 11 potential consensus sites for GLI trancription factors in the survivin promoter, albeit non of them has been a full consensus. Interestingly, the distal part of the promoter (-1765 to -941, ending at +39) containing 4 GLI sites showed about 2-fold higher activity than the proximal promoter (-941 to +39). The survivin promoter-reporter has been found to be upregulated mainly by plasmids encoding GLI2 and deltaN-GLI2, a more active GLI2 truncated mutant. Its activity was even higher than the Sp1 activity. The promoter-reporter plasmid is also inhibited by the GLI1/2 inhibitor GANT61. Moreover, by analyzing 40 human tumor cell lines of various origin, we have found that the endogenous survivin protein level substantially decreases after the incubation with GANT61 in most cell lines. Real-time PCR for the survivin mRNA in GANT61-sensitive cell lines showed a decrease by up to about 50 per cent. These data suggest that survivin may be a novel important target regulated by the Hedgehog/GLI signaling pathway, which has been reported previously to be deregulated in the majority of tumor types. The work was supported by the grant NT/14005 from IGA, Ministry of Health, Czech Republic.

Citation Format: Kateřina Vlčková, Lubica Ondrušová, Jiri Réda, Jiri Vachtenheim, Petra Záková. Survivin is a novel target of the Hedgehog/GLI signaling pathway in human tumor cell lines. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2135. doi:10.1158/1538-7445.AM2015-2135
Abstract 2146: RASSF1C modulation of Piwi-interacting RNAs (piRNAs) in lung cancer
Authors: Amaar Yousef G. , Firek Matthew , Reeves Mark E. , Reeves Mark E.
Published: August 2015

Introduction: RASSF1C is emerging as an important oncoprotein in lung cancer cell growth. We have shown that RASSF1C promotes lung cancer cell proliferation and migration; and RASSF1C up-regulates important genes in lung cancer cell growth that include a stem cell self-renewal gene, piwi1 (hiwi). PIWI-like proteins are a subfamily of Argonaute proteins that interact with small PIWI-interacting RNA molecules (known as piRNAs that are 24-32 nucleotides long) to form complexes that regulate transcriptional and translational repression. This leads to inhibition of apoptosis, stimulation of cell division and proliferation, and down-regulation of cyclin inhibitors and tumor suppressors. Therefore, modulation of Piwil1-piRNA gene expression by RASSF1C suggests a potential role for RASSF1C in lung cancer stem cell development and progression. To further investigate our hypothesis, we carried out a global piRNA microarray screen to identify piRNAs that are modulated by RASSF1C in lung cancer cells.

Method: A piRNA microarray screen was performed using the lung cancer cell line H1299 stably over-expressing RASSF1C (and controls). Total RNA was extracted from experimental and control cells and was submitted to Arraystar (Rockville, MD) for the piRNA microarray screen and data analysis.

Results: The piRNA microarray screen identified several piRNAs that are regulated by RASSF1C and we have confirmed the expression of some of them in cell lines. The function of the piRNAs identified is yet to be determined. We have initiated studies to determine the function of some of the most up-regulated and down-regulated piRNA genes in lung cancer cells. We are also profiling the expression of these piRNAs in normal and lung tumor tissues.

Conclusion: Several piRNAs are target genes of RASSF1C. Characterization of the function of these piRNAs may enhance our understanding of the role of RASSF1C in promoting lung cancer stem cell growth and progression. Linking a Rassf1c-Piwil1/piRNAs axis to lung cancer stem cell development and progression could possibly lead to discovery of new diagnostic and therapeutic targets for lung cancer.

Citation Format: Yousef G. Amaar, Matthew Firek, Mark E. Reeves, Mark E. Reeves. RASSF1C modulation of Piwi-interacting RNAs (piRNAs) in lung cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2146. doi:10.1158/1538-7445.AM2015-2146
Abstract 2149: N-deacetylase/N-sulfotransferase (heparan glucosaminyl) 4, a novel tumor suppressor, suppresses tumorigenesis and liver metastasis of colorectal cancer cells in mice
Authors: Jao Tzu-Ming , Tsai Ming-Hong , Tzeng Sheng-Tai , Yang Ya-Chien
Published: August 2015

Colorectal cancer (CRC) is one of the most common causes of cancer deaths in the world, and most of CRC arise sporadically by the emergence of multiple chromosomal aberrations. Allelic losses in the long arm of chromosome 4 are commonly encountered in many human malignancies, but few tumor suppressor genes (TSGs) are identified. By loss of heterozygosity study at chromosome 4 in 114 colorectal carcinomas, we identified N-deacetylase/N-sulfotransferase (heparan glucosaminyl) 4 (NDST4) as a novel TSG that had been published recently. We demonstrated for the first time that the genetic loss of NDST4 was significantly associated with advanced pathological stage and poorer overall survival of patients. Meanwhile, gene expression of NDST4 was obviously decreased in 30 (57.7%) of 52 CRC tumors when compared with their matched normal mucosae. In the present study, tumor suppressor activity of NDST4 was identified by in vitro cell models and mouse xenograft tumor models. Ectopic expression of NDST4 in the human CRC cells induced a significant suppression in cell proliferation, anchorage-independent growth and invasion in vitro. Subcutaneous injection of NDST4-inducible CRC cells in nude mice showed alleviated tumor growth in doxycycline treated mice when compared with doxycycline untreated mice. More importantly, via intrasplenic implantation, re-expression of NDST4 in silenced cells restrained liver metastasis, and also improved survival in nude mice. Taken together, these results indicate that NDST4 is a tumor suppressor gene associated with CRC, and its downregulation might promote tumor progression and distant metastasis. In addition, allelic loss of NDST4 gene could serve as a molecular predictor of metastasis and poor prognosis in patients with CRC.

Citation Format: Tzu-Ming Jao, Ming-Hong Tsai, Sheng-Tai Tzeng, Ya-Chien Yang. N-deacetylase/N-sulfotransferase (heparan glucosaminyl) 4, a novel tumor suppressor, suppresses tumorigenesis and liver metastasis of colorectal cancer cells in mice. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2149. doi:10.1158/1538-7445.AM2015-2149
Abstract 2163: Mapping SUMOylation sites of PTEN tumor suppressor
Authors: Wang Yubing , Wong Chiwai , Yan Mingfei , Or Penelope , Chan Andrew M.
Published: August 2015

PTEN tumor suppressor plays crucial function in multiple cellular processes, including proliferation, migration, DNA repair, cell cycle and survival signaling. Its function is tightly controlled by a series of regulatory processes at transcriptional and post-translational levels. Small ubiquitin-related modifier (SUMO) is an essential post-transcriptional modifier which involves in many important biological functions. Previous studies showed that PTEN can be modified by SUMOylation on K254 and K266. SUMOylation on K254 controls the nuclear localization and retention of PTEN and plays essential role in DNA damage repair. On the contrary, SUMOylation on K266 is responsible for its membrane binding, which is required for the down-regulation of PI3K/AKT pathway.

However, most studies mainly focus on SUMO1 modification, function of SUMO2/3 involved PTEN regulation is still unclear. In addition, the dynamic regulation and biological activities of different isoforms of SUMOylated PTEN in different subcellular compartments are not well-defined. Also, how PTEN phosphorylation impacted on PTEN SUMOylated have not been addressed fully.

To address these questions, a series of PTEN SUMOylation defective-mutants targeted to different subcellular compartments were generated. In addition, a panel of phosphorylation sites mutants (T366A, S370A, S380A, T382A, T383A, and S385A) were included. These mutants were cotransfected with His-tagged SUMO1, SUMO2, and SUMO3 in 293T cells. SUMOylated PTEN protein species are affinity absorbed onto nickel columns. The characterization of these mutants will be discussed.

To further delineate the dynamic regulation of SUMOylated PTEN, we are developing a BRET-based live cell imaging system by the ectopic co-expression of a HALO-tagged SUMO and NanoLuc-tagged PTEN expression constructs to monitor the subcellular localization of SUMO-conjugated PTEN in vivo.

This work was supported by Hong Kong Research Grant Council (460713) and Hong Kong PhD Fellowship Scheme (PF-12-13876).

Citation Format: Yubing Wang, Chiwai Wong, Mingfei Yan, Penelope Or, Andrew M. Chan. Mapping SUMOylation sites of PTEN tumor suppressor. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2163. doi:10.1158/1538-7445.AM2015-2163
Abstract 218: The new and rapid technique of detecting breast cancer cells using new fluorescent probe ‘gGlu-HMRG’ and its clinical application
Authors: Shinden Yoshiaki , Ueo Hiroki , Tobo Taro , Ganachi Ayako , Komatsu Hisateru , Nambara Sho , Saito Tomoko , Ueda Masami , Hirata Hidenari , Sakimura Shotaro , Takano Yuki , Uchi Ryutaro , Iguchi Tomohiro , Eguchi Hidetoshi , Sugimachi Keishi , Kubota Yoko , Kai Yuichiro , Kijima Yuko , Natsugoe Shoji , Ueo Hiraki , Urano Yasuteru , Mimori Koshi
Published: August 2015

Method

After spraying with gGlu-HMRG reagent to the samples, we took images within 5 minutes and analyzed the fluorescence intensity of them. Comparing the changes of fluorescence intensity and pathological evaluations, we examined how this fluorescent method could reflect the pathological status in resected breast tissues (n = 108 from 36 cases), margins of breast conserving surgery specimens (n = 7 from 5 cases) and axillary lymph nodes (n = 149 from 38 cases).

Result

1. The sensitivity and specificity were 92% and 94% respectively for binary classification (normal / abnormal) of various breast tissues.

2. We could detect all malignant lesions in the surface of surgical margins of breast conserving surgery specimens. Additionally, we could detect large tumor-free lesions as fluorescent negative regions.

3. The sensitivity and specificity were 97% and 79% respectively for diagnosing metastatic and non-metastatic axillary lymph nodes.

Discussion and conclusion

It was well feasible to distinguish breast tumor tissues from normal surrounding tissues by this new method. Since it is simple and non-tissue-destructive, it could be readily adopted in the clinical setting. We anticipate that it will reduce costs and the burden on histopathology services in the intraoperative pathological diagnosis of breast conserving surgery and sentinel lymph node biopsy. This technical innovation enable us to visualize tumor cells in the body intraoperatively and evolve the cancer surgery that needs the complete resection of cancer cells.

*1 Urano, Y. et al. Rapid cancer detection by topically spraying a γ-glutamyltranspeptidase-activated fluorescent probe. Sci. Trans. Med. 3, 110ra119 (2011).

Citation Format: Yoshiaki Shinden, Hiroki Ueo, Taro Tobo, Ayako Ganachi, Hisateru Komatsu, Sho Nambara, Tomoko Saito, Masami Ueda, Hidenari Hirata, Shotaro Sakimura, Yuki Takano, Ryutaro Uchi, Tomohiro Iguchi, Hidetoshi Eguchi, Keishi Sugimachi, Yoko Kubota, Yuichiro Kai, Yuko Kijima, Shoji Natsugoe, Hiraki Ueo, Yasuteru Urano, Koshi Mimori. The new and rapid technique of detecting breast cancer cells using new fluorescent probe ‘gGlu-HMRG’ and its clinical application. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 218. doi:10.1158/1538-7445.AM2015-218
Abstract 219: Fluorescence-guided surgery with an anti-CA 19-9-conjugated fluorophore in combination with neoadjuvant chemotherapy inhibits metastatic recurrence in a pancreatic cancer patient derived orthotopic xenograft (PDOX) nude mouse model
Authors: Hiroshima Yukihiko , Maawy Ali , Zhang Yong , Murakami Takashi , Momiyama Masashi , Mori Ryutaro , Matsuyama Ryusei , Katz Matthew H. , Fleming Jason B. , Chishima Takashi , Tanaka Kuniya , ichikawa Yasushi , Endo Itaru , Hoffman Robert M. , Bouvet Michael
Published: August 2015

The efficacy of fluorescence-guided surgery (FGS) in combination with neoadjuvant chemotherapy (NAC) with gemcitabine (GEM) on a pancreatic cancer patient derived orthotopic xenograft (PDOX) model was determined. A PDOX model was established from a CA19-9-positive, CEA-negative tumor from a patient who had undergone a pancreaticoduodenectomy for pancreatic adenocarcinoma. Mice were randomized to 4 groups: bright light surgery (BLS) only; BLS + NAC; FGS only; and FGS + NAC. An anti-CA19-9 or anti-CEA antibody conjugated to DyLight 650 was administered intravenously via the tail vein of mice with the pancreatic cancer PDOX 24 hours before surgery. The PDOX was brightly labeled with fluorophore-conjugated anti-CA19-9, but not with a fluorophore-conjugated anti-CEA antibody. FGS was performed using the fluorophore-conjugated anti-CA19-9 antibody. FGS + NAC significantly reduced the metastatic recurrence frequency to one of 8 mice, compared to FGS only after which metastasis recurred in 6 out of 8 mice, and BLS + NAC with metastatic recurrence in 7 out of 8 mice (p = 0.041). Thus NAC in combination with FGS can reduce or even eliminate metastatic recurrence of pancreatic cancer sensitive to NAC. The present study further emphasizes the power of the PDOX model which enables metastasis to occur and thereby identify the efficacy of FGS in combination with NAC on metastatic recurrence.

Citation Format: Yukihiko Hiroshima, Ali Maawy, Yong Zhang, Takashi Murakami, Masashi Momiyama, Ryutaro Mori, Ryusei Matsuyama, Matthew H. Katz, Jason B. Fleming, Takashi Chishima, Kuniya Tanaka, Yasushi ichikawa, Itaru Endo, Robert M. Hoffman, Michael Bouvet. Fluorescence-guided surgery with an anti-CA 19-9-conjugated fluorophore in combination with neoadjuvant chemotherapy inhibits metastatic recurrence in a pancreatic cancer patient derived orthotopic xenograft (PDOX) nude mouse model. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 219. doi:10.1158/1538-7445.AM2015-219
Abstract 2206: qPCR array of 84 cell cycle genes in oral squamous cell carcinoma reveals differently expressed genes in larger size tumors in relation to small tumors
Authors: Gomes Carolina C. , Diniz Marina G. , de Souza Fabricio T. , Correia-Silva Jeane F. , Gomez Ricardo S.
Published: August 2015

The aim of the study is to investigate if larger oral squamous cell carcinoma (OSCC) tumors show a different transcriptional signature of cell cycle genes in relation to small OSCC tumor samples. To address this issue, 17 fresh OSCC tumor samples were included in the study, including T1(n = 5),T2 (n = 9),T3 (n = 2) and T4 (n = 1) samples. All tumors were either from the tongue or from the floor of the mouth and only two patients were non-smokers. Two samples were from female patients, while the other 15 were from men. Samples were categorized according to clinical tumor size in tumors ≤ 2cm (T1 n = 5) or tumors > 2cm (T2, T3 and T4, n = 12). The median age of both groups was similar (57 and 62, respectively). The group of tumors ≤ 2cm was considered the reference group in the qRT-PCR results interpretation, while the larger tumors were considered the test group. The RNA was extracted and the cDNA was synthesized. A commercially available 84 cell cycle genes PCR array kit was used (PAHS-020, Cell Cycle PCR Array - Human, Qiagen). The results were analyzed according to the formula 2^-deltaCT and differential expressions were considered statistically significant when p<0.05. The target genes expressions were normalized to two housekeeping endogenous genes B2M and HPRT1, considering both, the geometric and arithmetic CT means (that differed less than 1 CT between the reference and test groups). The following genes were downregulated in the test group (larger tumors) compared to the reference group (smaller tumors), showing a minimum fold change of 4: ANAPC4, E2F4, CUL1, PCNA, KNTC1, RPL13A, KPNA2, NBN, CCNG2 and SUMO1. These results need to be further confirmed in a larger cohort of samples. In conclusion, these findings suggest that the transcriptional activity of specific cell cycle genes changes according to the size of the OSCC tumor, which probably reflects tumor molecular evolution.Supported by: FAPEMIG (Fundação de Amparo à Pesquisa de Minas Gerais), CNPq (National Council for Scientific and Technological Development) and CAPES (Coordination for Improvement of Higher Education Personnel), Brazil

Note: This abstract was not presented at the meeting.

Citation Format: Carolina C. Gomes, Marina G. Diniz, Fabricio T. de Souza, Jeane F. Correia-Silva, Ricardo S. Gomez. qPCR array of 84 cell cycle genes in oral squamous cell carcinoma reveals differently expressed genes in larger size tumors in relation to small tumors. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2206. doi:10.1158/1538-7445.AM2015-2206
Abstract 2215: Transcriptional co-regulation of Nox4 by p53 and SMAD3
Authors: Boudreau Howard E. , Park Jonathan J. , Leto Thomas L.
Published: August 2015

Recent studies suggest p53 plays an important role in TGF-beta-mediated cell signaling and migration. Previously, we showed that wild-type (WT) and mutant forms of p53 differentially regulate reactive oxygen species (ROS) generation by NADPH oxidase-4 (Nox4). We found that WT-p53 is a potent suppressor of TGF-beta-induced Nox4, ROS production, and cell migration, whereas tumor-associated mutant p53 proteins enhanced Nox4 mRNA and protein expression and cell migration by both TGF-beta-dependent and independent mechanisms (Boudreau et al. Br J Cancer. 2014 May 13;110(10):2569-82). In this study, we examined the basis of human Nox4 promoter regulation by p53 and SMAD3. By constructing a deletion series of Nox4 promoter-reporter constructs, we discovered two regions (-4.76kb to -3.9kb and -1.8kb to - 0.2kb) upstream of the transcription start site that induce promoter activity upon activation of the TGF-beta/SMAD3 pathway. Interestingly, TGF-beta/SMAD3-mediated Nox4 promoter activity was abolished by heterologous expression of p53-WT in p53-null cell lines Hep3B (hepatocytes) and H1299 (lung epithelial). This activity was repressed by wild-type p53 in a dose-dependent manner. In contrast, expression of common tumor-associated mutant-p53 proteins (R175H, R248H, R249Q, R273H) did not repress but enhanced Nox4 promoter activity. We observed this enhancement of Nox4 promoter activity by mutant p53 (R273H) in H1299 cells expressing T204D, a constitutively active TGF-beta receptor. When individual p53 response elements were mutated, however, both untreated and R273H-expressing cells showed 50% reduction in promoter activity. These results indicate that the Nox4 promoter region between -3.97kb and -4.76kb, containing candidate p53 response elements, plays a role in modulating Nox4 expression. Preliminary chromatin immunoprecipitation results suggest that endogenous mutant p53 R249S in PLC/PRF/5 hepatoma cells complexes with the Nox4 promoter region between -3.97kb and -4.76kb. Furthermore, constructs lacking this region show significantly reduced Nox4 promoter activity in response to TGF-beta. Our results provide a basis for Nox4 co-regulation by SMAD3 and mutant p53 that may be involved in tumor progression and metastasis.

Citation Format: Howard E. Boudreau, Jonathan J. Park, Thomas L. Leto. Transcriptional co-regulation of Nox4 by p53 and SMAD3. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2215. doi:10.1158/1538-7445.AM2015-2215
Abstract 2223: C-terminal truncated hepatitis B virus X protein promotes hepatocarcinogenesis through enhanced stemness and resistance to therapy
Authors: Ng Kai Yu , Chai Stella , Tong Man , Guan Xin-Yuan , Cheng Alfred S. , Ma Stephanie
Published: August 2015

Tumor relapse after chemotherapy typifies hepatocellular carcinoma (HCC) and is believed to be attributable to residual cancer stem cells (CSCs) that survive initial treatment. Chronic infection with hepatitis B virus (HBV) has long been linked to the development of HCC. Upon chronic infection, random HBV genome integration can lead to truncation of hepatitis B virus X (HBx) protein at the C-terminus. The resulting C-terminal-truncated HBx (HBx-ΔC) was previously shown to confer enhanced invasiveness and diminished apoptotic response in HCC cells. In this study, we found HBx-ΔC to be more frequently detected in HCC clinical samples than their matched non-tumor counterparts. In addition, we also identified a strong positive correlation between HBx-ΔC and the liver cancer stem cell marker CD133, in a panel of liver cell line tested. Subsequently, we delineated the role of a naturally occurring HBx-ΔC (HBx-Δ14) in promoting stemness and aggressive behaviors in HCC cells. The stable overexpression of HBx-Δ14 in HCC cell line (Huh7) and immortalized normal liver cell line (MIHA) promoted expression of stemness markers, EpCAM and SOX2. In vitro functional studies with HBx-Δ14 stably overexpressed in Huh7 demonstrated an increased ability to self-renew, resist chemotherapy (5-fluorouracil) and targeted therapy (sorafenib), migrate and induce capillary tube formation in endothelial cells. Similar functional results were also obtained when HBx-Δ14 was stably overexpressed in MIHA cells. Taken together, in addition to its role in enhancing HCC metastasis, we find HBx-Δ14 to confer cancer and stem cell-like features in HCC, and to play an important role in driving tumor relapse in this deadly disease.

Citation Format: Kai Yu Ng, Stella Chai, Man Tong, Xin-Yuan Guan, Alfred S. Cheng, Stephanie Ma. C-terminal truncated hepatitis B virus X protein promotes hepatocarcinogenesis through enhanced stemness and resistance to therapy. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2223. doi:10.1158/1538-7445.AM2015-2223
Abstract 2228: Requirement of JNK signaling for self-renewal and tumor-initiating capacity of ovarian cancer stem cells
Authors: Seino Manabu , Okada Masashi , Shibuya Keita , Seino Shizuka , Suzuki Shuhei , Takeda Hiroyuki , Ohta Tsuyoshi , Kurachi Hirohisa , Ito Kiyoshi , Nagase Satoru , Kitanaka Chifumi
Published: August 2015

Background/Aim: Activation of the c-JUN N-terminal kinase (JNK) signaling pathway has been associated with poor survival of patients with ovarian cancer, but the role(s) and significance of JNK signaling in ovarian cancer cells remain poorly understood. Here in this study, we aimed to investigate the role of JNK specifically in ovarian cancer stem cells (CSCs).

Materials and Methods: The effect of JNK inhibition on the self-renewal (CSC marker expression, sphere-forming ability) and tumor-initiating capacity was examined in CSCs derived from A2780 human ovarian cancer cell line. JNK inhibition was achieved either pharmacologically or genetically by use of RNA interference.

Results: Both pharmacological and genetic targeting of JNK resulted in loss of self-renewal and tumor-initiating capacity of A2780 CSCs.

Conclusion: Our findings demonstrate, to our knowledge for the first time, that JNK has a pivotal role in the maintenance of ovarian CSCs.

Citation Format: Manabu Seino, Masashi Okada, Keita Shibuya, Shizuka Seino, Shuhei Suzuki, Hiroyuki Takeda, Tsuyoshi Ohta, Hirohisa Kurachi, Kiyoshi Ito, Satoru Nagase, Chifumi Kitanaka. Requirement of JNK signaling for self-renewal and tumor-initiating capacity of ovarian cancer stem cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2228. doi:10.1158/1538-7445.AM2015-2228
Abstract 2229: CD117 expression and activation in prostate cancer progression
Authors: Kerr Bethany
Published: August 2015

We have demonstrated that CD117/c-kit expression on circulating tumor cells and in primary tumors correlates with advanced disease in prostate cancer patients. In addition, the ligand for CD117, stem cell factor (SCF) is increased in high-grade prostate cancer patients. To examine the effects of CD117 activation and expression on prostate cancer progression, we sorted CD117 positive and negative RM1 murine prostate cancer cells and LNCaP-C4-2 human prostate cancer cells. Sorted cells were then examined for tumorigenicity, proliferation, cell signaling, cell migration, angiogenesis and epithelial-mesenchymal transition. A xenograft model demonstrated that CD117 positive LNCaP-C4-2 tumors generate larger tumors characterized by increased vascularization and proliferation. In vitro, SCF induced CD117 activation results in altered cell signaling, migration and epithelial-to-mesenchymal transition. In addition, in vivo imaging of tumor growth demonstrated changes in tumor cell organization between CD117 positive and negative cell populations. In summary, CD117 expression and activation enhances prostate cancer progression.

Citation Format: Bethany Kerr. CD117 expression and activation in prostate cancer progression. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2229. doi:10.1158/1538-7445.AM2015-2229