bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 153: High neuropilin-1 expression on monocytes is positively associated with trastuzumab-mediated antibody-dependent cellular cytotoxicity of the HER2-overexpressing breast cancer cell line
Authors: Kawaguchi Kosuke , Suzuki Eiji , Kawashima Masao , Toi Masakazu
Published: May 2015

Purpose

Neuropilin-1 (Nrp1) was initially characterized as a guide for migrating cells and axons in developing nervous systems and is essential for the precise formation of neurons and vasculature. However, it was recently reported to also play an important role in the immune system. This study aimed to investigate the role of Nrp1 on monocytes in trastuzumab-mediated antibody-dependent cellular cytotoxicity (ADCC) targeting the HER2-positive human breast cancer cell line SKBR3. In addition, we evaluated the gene expression profile of monocytes expressing high and low levels of Nrp1.

Methods

Peripheral blood mononuclear cells from healthy volunteers were prepared using BD Vacutainer CPT Cell Preparation Tubes. The cells were stained with fluorescein isothiocyanate-conjugated anti-CD14 and allophycocyanin-conjugated anti-Nrp1 antibodies, and Nrp1high and Nrp1low monocyte subsets were sorted using FACSAria. These cells were used as effector cells in a conventional ADCC assay with SKBR3 as target cells and trastuzumab as the antibody. Target cell cytotoxicity was measured using the LDH cytotoxic test kit. The effector cell to target cell ratios of 20:1 and 10:1 were used. Gene expression analysis was performed by Affymetrix GeneChip microarrays. All study protocols were approved by the Ethics Committee for Clinical Research, Kyoto University Hospital, Kyoto, Japan (authorization number G424).

Results

The LDH cytotoxic test revealed significantly higher target cancer cell cytotoxicity in sorted Nrp1high monocytes than in Nrp1low monocytes (75% vs. 45%, p<0.01). Trastuzumab-mediated ADCC was significantly suppressed by Nrp1 neutralization antibodies in a dose-dependent manner (Control arm 14.3%, Treatment arm 6%; p<0.01). Gene expression analysis revealed that 308 genes were up-regulated in the Nrp1high population, including monocyte-specific chemokine receptor and hematopoietic transcriptional factor.

Conclusion

These results suggest that determination of Nrp1 expression can be used to classify monocytes as populations with and without cellular cytotoxic activity. Analysis of Nrp1 expression levels in monocytes can therefore be used to identify HER2-positive breast cancer patients for whom trastuzumab therapy will be less effective.

Citation Format: Kosuke Kawaguchi, Eiji Suzuki, Masao Kawashima, Masakazu Toi. High neuropilin-1 expression on monocytes is positively associated with trastuzumab-mediated antibody-dependent cellular cytotoxicity of the HER2-overexpressing breast cancer cell line. [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 153. doi:10.1158/1538-7445.AM2014-153
Abstract 1532: Exome and transcriptome profiling of lung adenocarcinoma in female never-smokers
Authors: Lee Sanghyuk , Kim Pora , Jun Yukyung , Park Charny , Kim Suyeon , Lee Hee-Young , Keum Juhee , Jung Yeonhwa , Jung Yeonjoo , Seo Chaehwa , Rho Kyoohyoung , Lee Jong-Eun , Kim Wankyu , Kim Jaesang , Kim Jhingook
Published: May 2015

Background: Lung cancer is the leading cause of cancer-related mortality in the world. TCGA projects for lung adenocarcinoma and squamous cell carcinoma are the largest datasets publicly available so far. They include diverse subtypes and population groups and thus small population groups such as female never-smokers in Asian are under-represented. Female never-smokers are an important population cohort where mutations due to genetic factors are enriched rather than environmental factors such as smoking. We applied the high throughput deep sequencing strategy to catalog somatic mutations and to profile gene expression levels for Korean patients.

Results: Deep sequencing data of exome and transcriptome were generated for tumor and matched normal tissues from 100 non-small-cell lung cancer (NSCLC) patients in female never-smokers. The mutational catalogue includes numerous somatic mutations, indels, and gene-fusion events. Comparison with TCGA lung cancer data shows that our patients harbor much less and homogeneous somatic mutations as expected. Mutational frequency and driver gene analyses identified many novel candidates of causal genetic variations. For example, our mutation spectrum reveals 5 key modules of enriched somatic mutations such as EGFR, p53, Wnt signaling pathways, ECM organization, and cell cycle checkpoints. Furthermore, network analysis of integrating mutation and expression data illustrates the detailed mechanism of dysregulation in tumorigenesis of lung adenocarcinoma.

Conclusion: Our study elucidates clinically important mutations and regulatory elements in NSCLC. It is expected that our dataset would serve as an important resource for lung cancer research especially in Asian populations.

Citation Format: Sanghyuk Lee, Pora Kim, Yukyung Jun, Charny Park, Suyeon Kim, Hee-Young Lee, Juhee Keum, Yeonhwa Jung, Yeonjoo Jung, Chaehwa Seo, Kyoohyoung Rho, Jong-Eun Lee, Wankyu Kim, Jaesang Kim, Jhingook Kim. Exome and transcriptome profiling of lung adenocarcinoma in female never-smokers. [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 1532. doi:10.1158/1538-7445.AM2014-1532
Abstract 1543: Systematic functional assessment of driver mutations for individual ovarian cancers
Authors: Mori Seiichi , Yokomizo Takako , Fujiwara Takeshi , Goto Osamu , Iwase Haruko , Kato Kazuyoshi , Kawaguchi Tokuichi , Noda Tetsuo
Published: May 2015

Although epithelial ovarian cancer is an intractable cancer and the overall five-year survival rate is approximately 40 to 50%, clinically effective molecular-targeted therapeutics to treat ovarian cancer has not been available thus far. Recent progress of massively parallel sequencing technologies has been enabling us to identify substantial number of genomic aberrations including somatic mutations, indels and translocations in variable cancer types exemplified by epithelial ovarian cancer and non-small cell lung cancer. However, it is still very difficult to identify a ‘driver’ gene, which is functionally relevant for cancer growth, from hundreds of mutations that are usually found from a single cancer sample of an individual patient. An in vitro cultured cell line, which is originated from a clinical sample, can be utilized to assess functions of the genes that are identified to have somatic aberrations in the paired clinical tumor. We have been establishing multiple ovarian cancer cell lines derived from clinical samples and analyzing pairs of the cell lines and clinical samples with exon-capture sequencing. The genes, which are somatically mutated and shared in a pair of cell line and clinical sample, are targeted with RNA interference in the cell line, and subsequently the effect on cell proliferation and survival is examined. As such, a driver mutation for an individual cancer can be identified by a set of experimental perturbations. Identified driver mutations would be then validated with publicly available databases and with clinical archive samples. As a proof-of-principle, somatic mutations of PIK3CA and KRAS were detected as drivers to promote cell proliferation of a carcinosarcoma. We believe this approach can increase an opportunity to identify molecular targets in ovarian cancer therapeutics.

Citation Format: Seiichi Mori, Takako Yokomizo, Takeshi Fujiwara, Osamu Goto, Haruko Iwase, Kazuyoshi Kato, Tokuichi Kawaguchi, Tetsuo Noda. Systematic functional assessment of driver mutations for individual ovarian cancers. [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 1543. doi:10.1158/1538-7445.AM2014-1543
Abstract 1546: The research of the mechanism of lung cancer carcinogenesis and the target gene of microRNA-20a in lung cancer small cells
Authors: Xiaogang Tan , Mu Hu , Xiuyi Zhi , Shimeng Jin
Published: May 2015

Purpose: Recent studies have suggested that microRNA biomarkers could be useful for stratifying lung cancer subtypes, but microRNA signatures varied between different populations. Small cell lung cancer (SCLC) is the lowest differentiation degree and the highest malignant subtype of lung cancer that urgently needs biomarkers to aid patient management. Here, we undertook the first comprehensive investigation on microRNA in Chinese SCLC patients of limited stage.

Experimental Design: MicroRNA expression was measured in cancerous and noncancerous tissue pairs strictly collected from Chinese SCLC patients of limited stage, who had not been treated with chemotherapy or radiotherapy prior to surgery. The molecular targets of proposed microRNA were further examined.

Results: We identified that high expression of hsa-miR-20a was associated with poor survival in these 20 SCLC patients by Kaplan-Meier analysis (P=0.03), This association was independently validated in a separate cohort of 38 SCLC patients in Kaplan-Meier analysis(P=0.046). We then determined that the tumor suppressor PTEN is a target of hsa-miR-20a. Expression of hsa-miR-20a in a human lung cancer cell line repressed PTEN activity.

Conclusions: Our results identified a new prognostic biomarker of SCLC, hsa-miR-20a.

Note: This abstract was not presented at the meeting.

Citation Format: Tan Xiaogang, Hu Mu, Zhi Xiuyi, Jin Shimeng. The research of the mechanism of lung cancer carcinogenesis and the target gene of microRNA-20a in lung cancer small 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 1546. doi:10.1158/1538-7445.AM2014-1546
Abstract 1548: Genomic and molecular profiling of NSCLC formalin-fixed paraffin-embedded tumors
Authors: Gaffney Dana S. , Bell Katherine , Martinez Gabriela , Rajpurohit Yashoda , Karkera Jayaprakash , Moy Christopher , Platero Suso
Published: May 2015

Non-Small Cell Lung Cancer (NSCLC) is the most common form of lung cancer, accounting for approximately 85% of all lung cancers worldwide. Standard therapy options include surgical resection followed by radiation and/or chemotherapy. More recently, analysis of the genomic profile of NSCLC has led to the development of molecularly targeted treatment strategies designed to enhance survival of select subsets of patients containing pre-determined genetic alterations, including gene mutations and aberrant gene expression profiles. In this study, we have developed a TaqMan-based approach to evaluate the genomic profile of 339 NSCLC FFPE tumors, consisting of 152 adenocarcinoma and 187 squamous cell carcinoma (SCC), stages I-IV. Using a custom qRT-PCR somatic mutation array, we have identified the frequencies of key mutations prevalent in NSCLC- associated genes, including EGFR: 5% SCC , 29% adenocarcinoma, cMET: 6% SCC, 4% adenocarcinoma, and KRAS: 3% SCC, 19% adenocarcinoma. Overall, these frequencies are concordant with previous reports. Additionally, we have evaluated the gene expression and IHC profiles of NSCLC-driver signaling pathways including EGFR, cMET and HGF. Various levels of expression for EGFR, cMET and HGF were observed across all samples, with a significant association detected between the presence of EGFR mutation and high EGFR expression in adenocarcinoma (p value = 0.0046). Overall, our findings represent a comprehensive catalog of common genetic aberrations with concurrent gene and protein expression profiles in NSCLC. Furthermore, this data provides insight into correlations observed across these molecular characteristics contributing to NSCLC tumor development. These insights can provide guidance for patient stratification and novel therapeutic strategies for select targeted therapies in NSCLC.

Citation Format: Dana S. Gaffney, Katherine Bell, Gabriela Martinez, Yashoda Rajpurohit, Jayaprakash Karkera, Christopher Moy, Suso Platero. Genomic and molecular profiling of NSCLC formalin-fixed paraffin-embedded tumors. [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 1548. doi:10.1158/1538-7445.AM2014-1548
Abstract 155: Expressions of autophagy-related proteins positively correlate with infiltration of immune cells and disease progression in oral squamous cell carcinoma
Authors: Sakakura Koichi , Takahashi Hideyuki , Kaira Kyoichi , Toyoda Minoru , Oyama Tetsunari , Chikamatsu Kazuaki
Published: May 2015

Introduction: Autophagy is an endogenous process that degrades bulk proteins and organelles to maintain energy homeostasis under cellular stress and nutrient starvation. It has been still unclear whether autophagy promotes or suppresses tumor progression in various cancer patients. To date, several studies have shown that autophagy-related molecules such as LC3 and Beclin-1 play important roles in tumor progression; however, few studies regarding immunological significance of these autophagy components in tumor microenvironment exist. The objective of this study is to clarify association between the expression of autophagy-related proteins and immune infiltrates by immunohistochemistry (IHC).

Patients and methods: Expression of two representative autophagy-associated molecules, LC3 and Beclin-1, and CD1a (dendritic cell), CD3 (T cell) and CD56 (NK cell) cells were examined by IHC in 74 patients with oral squamous cell carcinoma (OSCC). HLA class I heavy chain, HLA class II, Ki-67 and p53 were also stained and assessed. Two regions, central site and peripheral site in tumor tissues were evaluated, separately. Moreover, the association with various clinicopathological parameters including progression free and overall survival was evaluated.

Results: LC3 and Beclin-1 were accumulated in both 27 of 74 cases (36.5%) OCCC examined. LC3 expression in peripheral margin was significantly associated with increasing dendritic cell (DC) and T cell infiltration. Interestingly, peripheral Beclin-1 expression showed statistically significant relation to increasing HLA class II expression on tumor cells. On the other hand, LC3 and Beclin-1 significantly correlates with several unfavorable clinicopathological parameters including short overall survival. In addition, LC3 and Beclin-1 expression in OSCC significantly related to lymphatic invasion by tumor cells.

Conclusion: Significant association between LC3 and DC/T cell infiltration suggests that autophagy is likely to actively participate in immunological phenomena within tumor microenvironment. Furthermore, peripheral Beclin-1 may contribute to antigen presentation by tumor cells, while these two autophagy components also relates to unfavorable prognosis. Taken together, autophagy seems to promote immunogenicity of cancer cells, whereas it facilitates tumor progression.

Citation Format: Koichi Sakakura, Hideyuki Takahashi, Kyoichi Kaira, Minoru Toyoda, Tetsunari Oyama, Kazuaki Chikamatsu. Expressions of autophagy-related proteins positively correlate with infiltration of immune cells and disease progression in oral squamous 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 155. doi:10.1158/1538-7445.AM2014-155
Abstract 1552: CCN5/wisp-2 induced growth arrest of aggressive triple negative breast cancer cells is promoted through accumulation and trafficking of p27kip1
Authors: Haque Inamul , Banerjee Snigdha , De Archana , Maity Gargi , Sarkar Sandipto , McGragor Douglas , Banerjee Sushanta K.
Published: May 2015

CCN5, a matricellular protein, represents promising treatment target in triple negative breast cancer (TNBC) as treatment or induced activation of CCN5 in TNBC cells promotes cell growth arrest at G0/G1 phase, reduces cell proliferation and delays tumor growth in xenograft model. Our studies found that p27Kip1 tumor suppressor protein is upregulated and relocalized to the nucleus from cytoplasm by CCN5 in these cells and that these two events (i.e., upregulation and relocalization) of p27Kip1 is required for CCN5-induced growth inhibition of TNBC cells. In the absence of CCN5, p27Kip1 remains mostly in the cytoplasm, a state of aggressive nature of cancer cells. Mechanistically, CCN5 inhibits Skp2 expression, which seems to stabilize p27Kip1 protein in these cells. On the other hand, CCN5 also recruits FOXO3a to mediate transcriptional regulation of p27Kip1. The recruitment of FOXO3a is achieved by the induction of its expression and activity through shifting from cytoplasm to the nucleus. Our data indicate that CCN5 blocks PI3K/AKT signaling to dephosphorylate at S318, S253 and Thr32 in FOXO3a for nuclear relocalization and activation of FOXO3a. Inhibition of α6β1 diminishes CCN5 action on p27Kip1 in TNBC cells. Collectively, CCN5 may have therapeutic potential for TNBC.

Citation Format: Inamul Haque, Snigdha Banerjee, Archana De, Gargi Maity, Sandipto Sarkar, Douglas McGragor, Sushanta K. Banerjee. CCN5/wisp-2 induced growth arrest of aggressive triple negative breast cancer cells is promoted through accumulation and trafficking of p27kip1 . [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 1552. doi:10.1158/1538-7445.AM2014-1552
Abstract 1553: Rho guanine nucleotide exchange factor (ARHGEF) 10 is a putative tumor suppressor in pancreatic ductal adenocarcinoma
Authors: Joseph Joella , Radulovich Nikolina , Tsao Ming-Sound
Published: May 2015

Background: Pancreatic ductal adenocarcinoma (PDAC) accounts for over 90% of pancreatic malignancies, and is the fourth leading cause of cancer related deaths. Disease prognosis is quite poor, with less than 20% of patients eligible for curative surgical resection at time of diagnosis and overall survival rates of 2%. PDAC arises from the malignant transformation of ductal epithelial cells through progressive accumulation of loss of function mutations and deletions of tumor suppressor genes. Chromosome 8p has been shown to be a recurrent site of deletions in PDAC. Among the deleted genes is the Rho guanine nucleotide exchange factor 10 (ARHGEF10), a regulator of Rho signaling that is involved in mitotic spindle formation. Here, we evaluate ARHGEF10 for its potential role as a tumor suppressor in PDAC.

Methods: ARHGEF10 expression was assessed in 19 PDAC cell lines and in 53 patient tumor xenograft samples at both mRNA and protein levels. Publically available datasets were also used to determine correlation between ARHGEF10 mRNA expression and DNA copy number. After identifying PDAC cell lines with low ARHGEF10 expression, ARGHEF10 was stably overexpressed in these cell lines by lentiviral transduction. The effects of ARHGEF10 expression were then evaluated by in vivo tumorigenicity in immunodeficient mice, and by in vitro cell proliferation and cell motility wound healing assays.

Results: ARHGEF10 showed reduced expression in up to 70% of cell lines and patient tumor xenografts. Reduced ARHGEF10 expression correlated significantly with loss of copy number in PDAC cell lines. Stable overexpression of ARHGEF10 in PDAC cell lines significantly reduced tumor growth in immunodeficient mice. In addition, ARHGEF10 expression resulted in decreased cell motility in wound healing assays, but had minimal effect on cell proliferation. Experiments for in vitro assessment of invasion and changes in Rho activity are ongoing, and will be presented

Conclusions: This study suggests that ARHGEF10 may function as a tumor suppressor gene in PDAC.

Citation Format: Joella Joseph, Nikolina Radulovich, Ming-Sound Tsao. Rho guanine nucleotide exchange factor (ARHGEF) 10 is a putative tumor suppressor in pancreatic ductal adenocarcinoma. [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 1553. doi:10.1158/1538-7445.AM2014-1553
Abstract 1556: Regulation of cellular apoptosis via a novel protein-protein interaction of tumor suppressor p53 with the xenobiotic pregnane X receptor (PXR) in colon cancer cells
Authors: Robbins Delira F. , Wu Jing , Chen Taosheng
Published: May 2015

The cellular response to DNA damage comprises of DNA repair, cell-cycle checkpoint control and DNA damage-induced apoptosis to promote genomic integrity and suppress tumorigenesis. However, cancer cells can modulate the DNA damage response by suppressing DNA repair, altering cell cycle checkpoint control and ultimately downregulating tumor suppressors that contribute to apoptosis promoting genomic instability and avoidance of apoptosis.

Although PXR is well established as a xenobiotic nuclear receptor that plays a central role in xenobiotic metabolism and disposition, emerging evidence suggest PXR as a regulator of apoptosis, promoting a malignant phenotype, both in vitro and in vivo. The tumor suppressor p53 can be activated in the presence of DNA damage and can induce cell cycle arrest to allow for DNA repair, or ultimately apoptosis suppressing tumor formation. We hypothesized that the novel protein-protein interaction between PXR and p53 contributes to the oncogenic functions of PXR enhancing colon carcinogenesis. Using immunoprecipitation, we found that PXR forms a protein-protein interaction with p53, resulting in reduced p53 activation and expression of downstream pro-apoptotic genes. In addition, utilizing the soft agar assay, we found that PXR overexpression leads to increased malignant transformation in colon cancer cells. Our findings show for the first time that PXR can physically bind to p53, resulting in downregulation of p53 activity and increased malignant transformation in colon cancer cells. Thus, these results provide insight into the biological significance of novel protein-protein interactions with PXR and how the PXR-p53 protein-protein interaction influences p53-mediated mechanism of tumor suppression.

Citation Format: Delira F. Robbins, Jing Wu, Taosheng Chen. Regulation of cellular apoptosis via a novel protein-protein interaction of tumor suppressor p53 with the xenobiotic pregnane X receptor (PXR) in 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 1556. doi:10.1158/1538-7445.AM2014-1556
Abstract 1568: Cellular mechanisms of tumor regression following Myc inhibition
Authors: Lu Dan , Burkhart Deborah L. , Griffin Julian L. , Littlewood Trevor D. , Evan Gerard I.
Published: May 2015

Myc is a pleiotropic transcription factor associated with various aspects of cell growth. Tumor cells often have deregulated Myc expression, which consequently promotes uncontrolled proliferation. Recent work in our lab using a mouse model of lung cancer has demonstrated that expression of a dominant negative form of Myc causes tumor regression whilst having mild and reversible effects on normal proliferating tissues. However the cellular mechanism of how Myc inhibition leads to tumor regression is not known. Here we show that Myc inhibition causes metabolic changes in tumor cells associated with a reduced proliferative/biosynthetic state. Furthermore, we demonstrate that Myc inhibition leads to p21 expression independently of p53 and may account for tumor cell cycle arrest.

Citation Format: Dan Lu, Deborah L. Burkhart, Julian L. Griffin, Trevor D. Littlewood, Gerard I. Evan. Cellular mechanisms of tumor regression following Myc inhibition. [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 1568. doi:10.1158/1538-7445.AM2014-1568
Abstract 1569: The nuclear export signal (NES) within CALM is necessary for CALM-AF10-induced leukemia
Authors: Suzuki Mai , Yamagata Kazutsune , Aikawa Yukiko , Watanabe Toshio , Kitabayashi Issay
Published: May 2015

The CALM-AF10 fusion gene, which results from a t(10;11) translocation, is found in a variety of hematopoietic malignancies. Certain HOXA cluster genes and MEIS1 genes are upregulated in patients and mouse models that express CALM-AF10. Wild-type CALM primarily localizes in a diffuse pattern within the cytoplasm, whereas AF10 localizes in the nucleus; however, it is not clear where CALM-AF10 acts to induce leukemia. To investigate the influence of localization on leukemogenesis involving CALM-AF10, we determined the nuclear export signal (NES) within CALM that is necessary and sufficient for cytoplasmic localization of CALM-AF10. Mutations in the NES eliminated the capacity of CALM-AF10 to immortalize murine bone-marrow cells in vitro and to promote development of acute myeloid leukemia in mouse models. Furthermore, a fusion of AF10 with the minimal NES could immortalize bone-marrow cells and induce leukemia in mice. These results suggest that during leukemogenesis, CALM-AF10 plays its critical roles in the cytoplasm.

Citation Format: Mai Suzuki, Kazutsune Yamagata, Yukiko Aikawa, Toshio Watanabe, Issay Kitabayashi. The nuclear export signal (NES) within CALM is necessary for CALM-AF10-induced leukemia. [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 1569. doi:10.1158/1538-7445.AM2014-1569
Abstract 157: Lapatinib induces IL-6 expression via MAPK pathway in triple-negative breast cancer cells
Authors: Hsiao Yu-Chun , Chen Yun-Ju , Tang Chih-Hsin , Huang Wei-Chien
Published: May 2015

Lapatinib, the dual epidermal growth factor receptor (EGFR) and HER2 tyrosine kinase inhibitor (TKI), have been tested in triple negative breast cancer (TNBC) patients in several clinical studies. However, limited clinic benefit was observed, and the metastatic ability of TNBC cells was even unexpectedly enhanced by these anti-cancer drugs in our previous studies. In this study, we found that induction of interleukin-6 (IL-6) expression was induced in lapatinib-treated cells to contribute to their increased ability of migration. Treatment of cells with the IL-6 antibody abolished the lapatinib-induced cell migration. In response to lapatinib treatment, Raf-1, Mitogen-activated protein kinases (MAPK), c-Jun N-terminal kinases (JNK), p38 mitogen activated protein kinase (p38 or p38-MAPK), and activator protein 1 (AP-1) signaling pathways were activated to mediated the induction of IL-6 level. Furthermore, downregulation of miR-7 was found to result in the lapatinib-induced activation of Raf-1signaling pathway and IL-6 expression. Taken together, our results indicated that lapatinib enhanced the migratory ability of TNBC by increasing IL-6 expression via the Raf-1, MAPK, JNK, p38, and AP-1 pathways.

Citation Format: Yu-Chun Hsiao, Yun-Ju Chen, Chih-Hsin Tang, Wei-Chien Huang. Lapatinib induces IL-6 expression via MAPK pathway in triple-negative breast 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 157. doi:10.1158/1538-7445.AM2014-157
Abstract 1573: TUSC4 functions as tumor suppressor by regulating BRCA1 stability and functions
Authors: Peng Yang , Lin Shiaw-Yih
Published: May 2015

Expression of the BRCA1 tumor suppressor is frequently lost in breast cancer and associated with aggressive phenotypes through as yet undetermined mechanisms. In this study, we demonstrated that the tumor suppressor TUSC4 (Tumor Suppressor Candicate 4) physically interacts with multiple DNA damage response proteins and prevent its degradation by E3 ligase ubqutination pathways. Knockdown of TUSC4 enhanced BRCA1 polyubiquitination, leading to BRCA1 protein degradation and significantly reduced the efficacy of homologous recombination repair. Notably, ectopic expression of TUSC4 effectively suppressed multiple breast cancer cells proliferation, invasion, and colony formation in vitro and tumor growth in vivo. Furthermore, TUSC4 knockdown was sufficient to transform normal mammary epithelial cells and enhance the sensitivity of cells to PARP inhibitors. Microarray analysis of TUSC4 knockdown also indicated critical changes and the global impact to cancer development. Therefore, TUSC4 acts as a bona fide tumor suppressor gene through the mechanism of regulating BRCA1 protein stability and function.

Citation Format: Yang Peng, Shiaw-Yih Lin. TUSC4 functions as tumor suppressor by regulating BRCA1 stability and functions. [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 1573. doi:10.1158/1538-7445.AM2014-1573
Abstract 1574: CDK5 negatively regulates Rho by phosphorylating and activating the Rho-GAP and tumor suppressor functions of DLC1
Authors: Tripathi Brajendra K. , Qian Xiaolan , Mertins Philipp , Wang Dunrui , Papageorge Alex , Carr Steven , Lowy Douglas R.
Published: May 2015

The tumor suppressor Deleted in Liver Cancer 1 (DLC1) is frequently down-regulated in various human cancers, including breast, prostate, liver, and non-small cell lung cancer (NSCLC). Although the tumor suppressor function of DLC1 depends on its Rho-GAP (GTPase activating protein) activity, which converts Rho from the active GTP-bound form to the inactive GDP-bound form, the mechanisms regulating this activity are poorly understood. Here we determined that CDK5, a predominantly cytoplasmic serine/threonine kinase, negatively regulates Rho-GTP in normal and transformed cells that express DLC1, and that this regulation is attributable to the ability of CDK5 to activate DLC1. We found that CDK5, phosphorylates four serine residues (S120, S205, S422, S509) in the N-terminal region of DLC1, which reduces the binding of the N-terminus to the Rho-GAP domain. The phosphorylation of these serine residues stimulate the tumor suppressor activity of DLC1 - as determined by anchorage-independent growth and tumor xenograft formation - by increasing its Rho-GAP activity and facilitating its binding of several ligands. Serine-to-alanine mutations of the 4 serines increased binding between the DLC1 N-terminus and its Rho-GAP domain, resulting in a mutant protein that lacked these activities. We infer that the N-terminus of DLC1 functions as an auto-inhibitory domain that binds the Rho-GAP domain, and that phosphorylation of the N-terminal 4 serines by CDK5 reduces this interaction, activateing the Rho-GAP and tumor suppressor activities of DLC1. Interestingly, in NSCLC, the expression of CDK5, which has numerous targets, can be associated with a poor prognosis, suggesting that its activity in NSCLC might select for down-regulation of DLC1. Consistent with this hypothesis, we found that siRNA knock-down of endogenous DLC1 in a NSCLC line greatly increased the ability of CDK5 to stimulate neoplastic growth of the line. We also found, in a publicly available tumor database, that poorly differentiated NSCLC is much more likely to express high levels of CDK5 mRNA together with low levels of DLC1 mRNA than is well differentiated NSCLC. Thus, we have identified negative Rho regulation as a new function for CDK5, found DLC1 is the key target for this regulation, elucidated a CDK5-dependent post-translational modification for activating DLC1, and demonstrated the relevance of these observations to NSCLC.

Citation Format: Brajendra K. Tripathi, Xiaolan Qian, Philipp Mertins, Dunrui Wang, Alex Papageorge, Steven Carr, Douglas R. Lowy. CDK5 negatively regulates Rho by phosphorylating and activating the Rho-GAP and tumor suppressor functions of DLC1. [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 1574. doi:10.1158/1538-7445.AM2014-1574
Abstract 1576: Characterization of a mouse line lacking the PDZ-binding domain of PTEN
Authors: Chan Andrew M. , Guan Hong , Many Alex M.
Published: May 2015

PTEN encodes a phosphatase for phosphatidylinositides and serves as a key negative regulator of the phosphatidylinositol 3-kinase signaling pathway. PTEN possesses a carboxyl-terminal Postsynaptic density-95/Dlg-1/ZO-1-binding domain (PDZ-BD) implicated in membrane targeting. Since the physiological function of this domain was unclear, a mouse strain lacking this domain was generated. PtenΔPDZ/ΔPDZ mice developed normally although the haploinsufficient mice (PtenΔPDZ/-) were under represented by 50% based on Mendelian ratio of inheritance. PtenΔPDZ/- mice that survived to adulthood harbored a ∼8 % increase in brain masses when compared to PTEN heterozygous (Pten+/-) animals. However, PtenΔPDZ/- mice do not have a greater propensity in neoplastic progression of the prostate, lymph nodes, and endometrium. Independently, the Primary astrocytes from PtenΔPDZ/ΔPDZ mice displayed marginally greater Akt activation following stimulation by epidermal growth factor although both proliferative and migratory capacities were not altered. Crossing PtenΔPDZ/ΔPDZ mice with a breast cancer model, MMTV-PyMT; and a glioblastoma model, GFAP-Ha-Ras, resulted in enhanced metastasis and reduced survival, respectively. Overall, these data provide the first demonstration of a physiological relevance of PTEN PDZ-BD in embryonic development, brain size regulation and tumor progression.

Citation Format: Andrew M. Chan, Hong Guan, Alex M. Many. Characterization of a mouse line lacking the PDZ-binding domain of PTEN. [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 1576. doi:10.1158/1538-7445.AM2014-1576
Abstract 1580: Age-related difference in the susceptibility phthalate-induced injury in Sprague-Dawley rat
Authors: Traore Kassim
Published: May 2015

Di-2-ethylhexyl phthalate (DEHP), a commonly used plasticizer of synthetic polymers causes liver tumorigenesis, and both short and long-term effects on the reproductive system of male rats. Whether initial exposures to DEHP in early developmental stage affect the susceptibility to injury by subsequent exposures later in life remain unknown. Pregnant dams of Sprague Dawley rats were gavage with vehicle, 100 or 750 mg/kg bw/day of DEHP from Gestational Day 14 (GND14) until birth. After resting for twenty days, at postnatal day 21 (PND21) male offspring were gavage with vehicle, DEHP (100 or 750 mg/Kg/d) for 14 days (PND21-35). On PND35, offspring were sacrificed, serum testosterone (T) levels, body and organ (testis, liver and kidney) weight were examined. The data reveals that DEHP 750 mg/Kg/d but not 100mg/Kg/d treatment were sufficient to cause damage to testis when exposures occurs during either gestational or peripubertal (PND21-35) period. Interestingly, our data also indicated that subsequent exposures to DEHP (100 mg/Kg/day) in utero and at peri-pubertal stage were also effective to causing significant injury to testis. The serum T levels were reduced in all DEHP treatment groups. Next, we investigated the effects of peripubertal exposure to DEHP on the susceptibility to injury by subsequent exposure during adulthood. PND21 rats were subjected to oral administration of Oil, DEHP (100mg/kg/day or 750mg/kg/day) for 14 days (PND21-35). The rats were allowed to rest for 25 days until PND60. At PND60, rats were divided into groups and subsequently exposed to oil or DEHP (100 or 750 mg/Kg/d) for 14days (PND60-74). At PND74 the rats were sacrificed, serum T levels, body and organ weights were determined. Interestingly, no significant injury was observed in any of the treatment groups. Instead, and enhanced serum T levels were observed in DEHP-treated adult rats compared to control. Together, this study shows that the susceptibility to injuries following subsequent DEHP exposure is age-dependent, with immature male rats more susceptible while adults are resistant. In addition, the data also indicated that injuries sustained during peri-pubertal exposure are at least in part reversible. This work was supported by NIH-NIGMS-SCORE 2 grant SC2GM099578.

Citation Format: Kassim Traore. Age-related difference in the susceptibility phthalate-induced injury in Sprague-Dawley rat. [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 1580. doi:10.1158/1538-7445.AM2014-1580
Abstract 1581: Ethanol overrides DNA synthesis inhibition in response to PAHs (tobacco smoke carcinogens): a mechanistic explanation
Authors: Mukherjee Jagat J. , Kumar Subodh
Published: May 2015

It is a well-established fact that alcohol intake with smoking presents a potential health risk to human. Mechanistic understanding in this regard is not clear. We previously reported that DNA damage by tobacco smoke carcinogens polynuclear aromatic hydrocarbons (PAHs) is responded by cells through induction of cell growth inhibition in different cell lines. Here we observed that ethanol (EtOH) treatment at physiologically relevant concentration (60 mM) increases DNA synthesis in DNA damaging carcinogen (BPDE) treated cells. BPDE treatment of cells elicits G1-S cell cycle arrest, but EtOH does not have any significant modulating effect on G1-S arrest indicating increased DNA synthesis by EtOH is due to modulation of some other signaling event(s). EtOH co-treatment/pretreatment is unable to modulate BPDE-induced p53 accumulation and p53 phosphorylation at ser15 and ser20 indicating increased DNA synthesis by EtOH is p53 independent. We also observed that EtOH co-treatment/pretreatment potentiates BPDE-induced phosphorylation and activation of ERKs only and not p38 MAPK. Interestingly, treatment of cells with MEK1 inhibitor (PD098059) significantly reduced ethanol's ability to increase DNA synthesis in BPDE treated cells. This finding indicates that the ability of EtOH to potentiate BPDE-induced ERK activation may potentiate PAH-induced tumorigenesis.

Note: This abstract was not presented at the meeting.

Citation Format: Jagat J. Mukherjee, Subodh Kumar. Ethanol overrides DNA synthesis inhibition in response to PAHs (tobacco smoke carcinogens): a mechanistic explanation. [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 1581. doi:10.1158/1538-7445.AM2014-1581
Abstract 1586: Toxicity screening, apoptosis hallmark events and nitro reduction of novel quinolinium salts (BQS) on lymphoma cells
Authors: Rios-Rodriguez Karoline , Soto Jessica , Velez Christian , Cox Osvaldo , Rivera Juan P. , Zayas Beatriz
Published: May 2015

The main purpose of this research was to evaluate the effects of two novel benzazolo[3,2-a]quinolinium salts (ABQ-48 and NBQ48) on lymphoma cells (TOLEDO). The cationic nature of these BQS can facilitate its interaction with cell organelles such as mitochondria and DNA. To determine its potential cytotoxic effects the compounds were screened through the NCI 60 cell line protocol which determines the cell viability inhibitory activity in various cancer histological types. The IC50 dose for these compounds was determined and used to assess their apoptosis induction capacity evaluating apoptosis hallmark events such as DNA Fragmentation, Caspase 3&7 activators and mitochondrial membrane permeabilization. Additionally cell reduction potential of the compounds was measured. Results from the NCI 60 cell line protocol demonstrated the toxicity of BQS in multiple cancer types including breast and colon cancer cells. Preliminary results indicated mitochondrial membrane permeabilization on cells treated with NBQ48 (51.3%) and ABQ48 (57.67%) comparable to the positive controls camptothecin (51.6%) and valinomycin (55.3%). Treated cells also presented DNA fragmentation with NBQ48 and ABQ48 (28%) comparable to the positive control 37%. Preliminary data for caspases 3&7 activation strongly suggest an intrinsic apoptosis pathway. Analysis of the reduction of nitro substituted compound NBQ 48 to the amino substituted ABQ 48 on treated cells was determined by measuring an increment on fluorescence emission, characteristic of an amino specie. In conclusion, the study provides evidence of the induction of key apoptotic events as part of the mechanism of action of these novel BQS.

Citation Format: Karoline Rios-Rodriguez, Jessica Soto, Christian Velez, Osvaldo Cox, Juan P. Rivera, Beatriz Zayas. Toxicity screening, apoptosis hallmark events and nitro reduction of novel quinolinium salts (BQS) on lymphoma 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 1586. doi:10.1158/1538-7445.AM2014-1586
Abstract 1590: Expression and function of Sirt6 in muscle invasive bladder cancer
Authors: Wu Minghui , Dickinson Shohreh , Zhang Jingsong
Published: May 2015

Unlike most other solid tumors, there is limited success of targeted agents in treating metastatic bladder cancer (BC), a lethal disease with a median overall survival of merely 13-15 months. No prevalent “drugable” driver mutations have been identified in muscle invasive bladder cancer (MIBC) so far. Several high profile publications in the past few years have put Sirt6, a member of the class III histone deacetylase in the center stage of cancer metabolism and DNA repair. We therefore assessed the expression and function of Sirt6 in MIBC. Inconsistent with its proposed function as a tumor suppressor in colon cancer, the gene expression datasets available in Oncomine did not reveal significant differences in Sirt6 mRNA levels among normal urothelium, superficial BC and MIBC. Compared to normal urothelium, carcinoma in situ, superficial BC, the median Sirt6 mRNA was the lowest in MIBC in the Dyrkjot bladder 3 dataset, but this was not statistically significant. We then studied Sirt6 protein expression with immunohistochemistry (IHC) in commercial tissue microarray as well as radical cystoprostatectomy samples in our total cancer care tumor bank. Sirt6 IHC were reviewed by pathologist and considered positive for Sirt6 if more than 5% of the tumor cells had at least 1+ Sirt6 nuclear staining. Positive Sirt6 IHC was detected in 33/56 (59%) of T2 (grade 1-3), 2/23 T3 (9%) and 0/3 T4 urothelial carcinoma. All the grade 3/high grade T3 urothelial carcinomas were negative for Sirt6 IHC. Negative Sirt6 IHC was also noted in 2 adenocarcinomas, 1 sarcomatoid carcinoma and 1 small cell MIBC. 1/18 (5%) lymph node metastasis had positive Sirt6 IHC. Consistent with its role of inhibiting aerobic glycolysis, bladder cancer cell lines with higher Srit6 have lower glucose uptake and lower lactate production. Knocking down Sirt6 expression in bladder cancer cell lines, however, did not sensitize bladder cancer lines to drug induced DNA damage. Among MIBC, much higher frequency of Sirt6 IHC positivity was noted in T2 urothelial carcinoma than T3, T4 and non-urothelial carcinomas. Data with bladder cancer cell lines suggest the function of Sirt6 in bladder cancer is primarily inhibiting aerobic glycolysis.

Citation Format: Minghui Wu, Shohreh Dickinson, Jingsong Zhang. Expression and function of Sirt6 in muscle invasive bladder 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 1590. doi:10.1158/1538-7445.AM2014-1590
Abstract 1596: CXCL13 as a mediator of oncogenic PKCϵ in prostate cancer
Authors: Garg Rachana , Abba Martin , Kazanietz Marcelo G.
Published: May 2015

Protein kinase C epsilon (PKCϵ), a member of the PKC family of phorbol ester/diacylglycerol receptors, has emerged as an oncogenic kinase and plays important role in cell survival, mitogenesis and invasion. PKCϵ is up-regulated in most epithelial cancers, including prostate cancer. We recently showed that transgenic PKCϵ overexpression in the mouse prostate under the control of probasin (PB) promoter leads to hyperplasia and prostatic intraepithelial neoplastic lesions but is insufficient to drive neoplastic changes. Strikingly, when we intercrossed the prostate-specific PKCϵ transgenic mice with mice haploinsufficient for Pten, a common genetic alteration in human prostate cancer, the resulting compound mutant mice (PB-PKCϵ;Pten+/- mice) developed fully invasive adenocarcinoma (unpublished observation). In the present study, to explore the mechanistic aspects of the observed cooperativity between PKCϵ overexpression and Pten deficiency, we stably overexpressed PKCϵ in mouse prostate epithelial lines that are either heterozygous (P8) or homozygous (CaP8) for Pten deletion. PKCϵ overexpression led to significant enhancement in cell proliferation as well as enhanced the levels of phospho-Akt, phospho-Erk and phospho-mTOR; these effects are more pronounced in CaP8 cells. Moreover, migration, invasion, clonogenic and soft agar colony formation assays revealed a striking synergism between PKCϵ overexpression and Pten loss. Furthermore, analysis of global gene expression by microarray revealed significant changes in gene related to EMT, adhesion, metabolism, and invasiveness following PKCϵ overexpression, Pten loss or both. In particular, a chemokine CXCL13 was found to be majorly up-regulated in CaP8-PKCϵ cells. Measurement of CXCL13 mRNA by qPCR or CXCL13 release to the conditioned medium (CM) by ELISA showed increased levels in PKCϵ overexpressing or Pten depleted cells, and these effects were synergistically enhanced in CaP8-PKCϵ cells. Remarkably, CM from CaP8-PKCϵ cells led to significant induction in growth and motility of P8 cells. Importantly, CXCL13 RNAi depletion reduced the proliferative and migratory capacity of CaP8-PKCϵ cells, thereby establishing the potential relevance of CXCL13 in the phenotypic effects of PKCϵ overexpression and Pten loss. Concurrently, the growth and motile activity of P8 cells were enhanced in response to exogenously added CXCL13. Overall, our results argue for the role of CXCL13 in mediating effects of oncogenic PKCϵ in prostate cancer.

Citation Format: Rachana Garg, Martin Abba, Marcelo G. Kazanietz. CXCL13 as a mediator of oncogenic PKCϵ in prostate 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 1596. doi:10.1158/1538-7445.AM2014-1596