bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 3019: GIPC high expression rescues BRCA2 deficiency and promotes tumorigenesis
Authors: Ding Xia , Sharan Shyam K.
Published: August 2015

Breast cancer is the most prevalent cancer in women worldwide and mutation in breast cancer susceptible gene 2 (BRCA2) is one of the genetic factors conferring highest risk (40-70%) of developing breast cancer. Although BRCA2 proteins are known to maintain genomic stability mainly by homologous recombination-mediated DNA repair, a detailed mechanism of how BRCA2 loss induces tumorigenesis remains unclear. Interestingly, BRCA2 null mice display embryonic lethality, while inactivation of both alleles of BRCA2 in tumor cells renders them able to survive and are predisposed to tumorigenesis only when there are mutations in BRCA2 genetic interactors. In the current study, we tried to identify such genes using a mouse embryonic stem cell (mESC)-based insertional mutagenesis screen. In mESCs with one knockout allele of Brca2 and the other allele flanked by loxP sites, cell death can be induced by Cre-mediated loss of the conditional allele. To identify genes whose up-regulation can rescue cell death induced by loss of BRCA2, we transduced these mESC with murine stem cell retrovirus (MSCV) expressing Cre recombinase. We obtained Brca2-null mESCs that were rescued by the viral insertion and used them to clone the viral insertion sites. We identified several candidate genes that were up-regulated in viable mESCs. One of these genes encodes a PDZ domain-containing protein, GIPC3, and expression of Gipc3 mRNA was elevated 3 to 4-fold in the rescued clone. We were able to rescue lethality of Brca2-null mESC by overexpressing GIPC3. The rescued cells lost RAD51 foci formation in response to irradiation and were hypersensitive to DNA damaging agents and exhibited an overall increase in genomic instability. Mechanistically, GIPC3 can bind to APPL1 and APPL2, two adaptor proteins involved in AKT-mediated cell survival pathway. We found an increased level of the active form of AKT in GIPC3-rescued cells, and a knock down of APPL1 and APPL2 blocked the rescue by GIPC3 overexpression. We found that the Gipc3 transgene can partially rescue the lethality of Brca2 null embryos and contribute to tumorigenesis in K14-Cre; Brca2cko/cko mice. Besides GIPC3, another GIPC family member, GIPC1 can also rescue BRCA2 loss-induced lethality in mESCs. Oncomine analysis showed Gipc2 mRNA up-regulation in BRCA1 deficient human breast tumors, suggesting the possibility that high expression of all the GIPC family members (GIPC1, 2 and 3) might facilitate BRCA1 or BRCA2-loss induced tumorigenesis.

Citation Format: Xia Ding, Shyam K. Sharan. GIPC high expression rescues BRCA2 deficiency and promotes tumorigenesis. [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 3019. doi:10.1158/1538-7445.AM2015-3019
Abstract 3038: G quadruplex stabilization induces mitophagy in S. cerevisiae
Authors: Stundon Jennifer
Published: August 2015

G-quadruplex (G4) DNA structures are stable planar structures held together by multiple G-G base pairs. G4 structures are thought to affect transcription and other chromosomal processes but their presence in vivo is also expected to slow replication fork progression. Previous work from our lab demonstrates that the S. cerevisiae Pif1 5′ to 3′ DNA helicase is a particularly potent unwinder of G4 structures in vitro1. In addition, cells lacking the Pif1 helicase exhibit replication fork slowing and DNA breakage at G4 motifs, chromosomal sequences that form intra-molecular G4 structures in vitro1,2. In addition, treating yeast in vivo with the G4 stabilizing drug PhenDC3 increases G4-mediated genome instability3.

We treated a collection of 4,783 S. cerevisiae strains that each contained a single gene deletion with PhenDC3 to search for genes that are sensitive or resistant to PhenDC3. We will discuss results showing that several yeast genes that affect maintenance of mitochondrial DNA and autophagy induction are hypersensitive to PhenDC3. Using fluorescent microscopy and immunoblotting, we further demonstrate that treatment of wild type S. cerevisiae cells with PhenDC3 induces autophagy, and more specifically, mitophagy. Moreover, cells lacking Pif1 are themselves activated for autophagy.

Reference:

1 Paeschke, K. et al. Pif1 family helicases suppress genome instability at G-quadruplex motifs. Nature 497, 458-+, doi:10.1038/nature12149 (2013).

2 Paeschke, K., Capra, J. A. & Zakian, V. A. DNA replication through G-quadruplex motifs is promoted by the Saccharomyces cerevisiae Pif1 DNA helicase. Cell 145, 678-691, doi:10.1016/j.cell.2011.04.015 (2011).

3 Piazza, A. et al. Genetic instability triggered by G-quadruplex interacting Phen-DC compounds in Saccharomyces cerevisiae. Nucleic Acids Res 38, 4337-4348, doi:10.1093/nar/gkq136 (2010).

Citation Format: Jennifer Stundon. G quadruplex stabilization induces mitophagy in S. cerevisiae. [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 3038. doi:10.1158/1538-7445.AM2015-3038
Abstract 3054: Bioenergetic signature of stromal cells defines the aggressiveness of prostate cancer
Authors: Vayalil Praveen Kumar , Landar Aimee
Published: August 2015

Cancer-associated fibroblasts, though derived from multiple lineages, share common as well as unique characteristics and play a critical role in various aspects of neoplasia. Their activities range from contributing to tumor formation to promoting the growth and invasion of tumors. They also promote angiogenesis, provide a metabolically friendly tumor environment, and confer resistance to chemotherapy and radiation. Clinical trials targeting stromal cells were disappointing. The reason underlying this failure has been ascribed to the fact that stromal cells do change during cancer progression to aggressive form. As the cancer progresses, both prostate cancer cells as well as stromal cells have to ‘functionally adapt’ to the microenvironment within the tumor mass and mutually support their growth in a hostile environment. The major environmental factor that molds the biology of cancer cells and stromal components is low oxygen tension within the tumor. The key cellular organelle that is functionally affected by exposure to different oxygen tensions is the mitochondria. In this study we present the data on the progressive changes in the stromal cell mitochondrial function in relation to the aggressiveness of prostate cancer at atmospheric oxygen and at different oxygen tensions. This study reveals the potential use of mitochondrial functional assay for the screening of compounds that specifically target the bioenergetics of stromal cells. This information may also unravel the metabolic interaction between tumor- microenvironment that contributes to tumor development and progression of prostate cancer and potential mechanism of resistance to therapy offered by stromal cells.

Citation Format: Praveen Kumar Vayalil, Aimee Landar. Bioenergetic signature of stromal cells defines the aggressiveness of prostate 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 3054. doi:10.1158/1538-7445.AM2015-3054
Abstract 3059: miR-518c-5p promotes the metastasis of oral cancer cells in a CXCR4-dependent and -independent manner
Authors: Kinouchi Makoto , Uchida Daisuke , Kuribayashi Nobuyuki , Tamatani Tetsuya , Nagai Hirokazu , Kawamata Hitoshi , Miyamoto Youji
Published: August 2015

We have demonstrated that CXCR4 system is involved in the metastatic process of oral cancer. Recently, we identified the miR-518c-5p as a downstream target of the CXCR4 system, which was involved in the metastasis of B88, a CXCR4-expressing oral cancer cell line (2014 AACR annual meeting). In this study, we examined the function of miR-518c-5p in an oral cancer cell line, CAL27, which did not express CXCR4 and did not exhibit metastatic potential in vivo. We transfected a miR-518c expression vector into parental CAL27 cells and isolated a stable transfectant, CAL27-518c. We could detect the upregulation of miR-518c-5p in the miR-518c transfectants compared with mock cells, which was completely inhibited by treatment with the miR-518c-5p LNA inhibitor. The growth and migration of CAL27-518c cells were significantly enhanced compared with those of mock cells. The miR-518c-5p inhibitor significantly impaired the enhanced cell growth and migration of CAL27-518c cells, indicating that these phenomena were mainly dependent on the expression of miR-518c-5p. Next, we examined the function of miR-518c-5p in vivo. miR-518c or mock transfectants were inoculated into the masseter muscle or the blood vessels of nude mice. Tumor volume, lymph nodes metastasis, and lung metastasis were significantly increased in the mice inoculated with miR-518c transfectants. These results indicate miR-518c-5p promotes the metastasis of oral cancer in a CXCR4-dependent and -independent manner.

Citation Format: Makoto Kinouchi, Daisuke Uchida, Nobuyuki Kuribayashi, Tetsuya Tamatani, Hirokazu Nagai, Hitoshi Kawamata, Youji Miyamoto. miR-518c-5p promotes the metastasis of oral cancer cells in a CXCR4-dependent and -independent manner. [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 3059. doi:10.1158/1538-7445.AM2015-3059
Abstract 3061: In vivo role of miR-32 in prostate cancer
Authors: Latonen Leena , Scaravilli Mauro , Zhang Fuping , Ruusuvuori Pekka , Poutanen Matti , Visakorpi Tapio
Published: August 2015

The androgen receptor (AR) signaling pathway is central to the emergence of castration-resistant prostate cancer (CRPC). We set out to identify androgen-regulated microRNAs (miRNAs) that may contribute to the development of CRPC. We found miR-32 to be an androgen regulated miRNA which is differentially expressed in CRPC compared to benign prostatic hyperplasia (BPH) and able to provide a significant growth advantage to LNCaP cells by reducing apoptosis

To study how increased miR-32 expression contributes to prostate cancer formation and/or progression in vivo, and to search for in vivo targets of miR-32 in the prostate tissue, we have established transgenic mice expressing miR-32 specifically in the prostate. FVB/N mouse strain was used to create transgenic mice with probasin promoter (ARR2PB) driving expression of miR-32 androgen-responsively in prostate epithelium post-puberty. The mice develop and breed normally, and express the transgene specifically in the ventral and dorsolateral lobes of the prostate, with no transgene expression detected in anterior prostate or seminal vesicles up to six months of age. To provoke lesions in prostate epithelium, the miR-32 mice were cross-bred with mice heterozygous for tumor suppressor Pten. Histological analysis of the prostates of ARR2PB-miR-32xPten+/- mice shows increased number of prostatic intraepithelial neoplasia (PIN) lesions in the dorsal prostate compared to Pten+/- mice. In addition, transgenic miR-32 can induce goblet cell metaplasia in prostate epithelium in lateral to ventral prostate, in addition to stromal responses, in the prostate in the Pten+/- background.

In search for in vivo targets of miR-32, we have performed a gene expression microarray analysis comparing the wild type and ARR2PB-miR-32 prostate tissue. Several candidate targets have been identified, and will be discussed further for their potential cancer relevance.

We find that miR-32 is potentially an important gene in the progression of prostate cancer and a putative drug target. We are currently analyzing histology of the miR-32 transgenic mouse prostates further, and assessing tissue targets of miR-32. With the transgenic mouse model, we aim to determine whether miR-32 is an oncomiR for prostate cancer in vivo, and will assess the potency of miR-32 as a therapeutic target.

Citation Format: Leena Latonen, Mauro Scaravilli, Fuping Zhang, Pekka Ruusuvuori, Matti Poutanen, Tapio Visakorpi. In vivo role of miR-32 in prostate 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 3061. doi:10.1158/1538-7445.AM2015-3061
Abstract 3062: miR-671-5p promotes epithelial-to-mesenchymal transition by downregulating FOXM1 expression in breast cancer
Authors: Tan Xiaohui , Fu Yebo , Chen Liang , An Shejuan , Lee Woojin , Lai Yinglei , Rezaei Katayoon , Tabbara Sana , Teal Christine B. , Man Yan-gao , Siegel Robert , Brem Rachel F. , Fu Sidney W.
Published: August 2015

microRNA (miRNA) dysfunction is associated with a variety of human diseases including cancer. Our previous study showed that miR-671-5p was deregulated during breast cancer progression. We aim to decipher the functional mechanism of miR-671-5p in breast cancer. We found that expression of miR-671-5p was decreased significantly in ductal carcinoma in situ (DCIS) and invasive ductal carcinoma (IDC) compared to normal and atypical ductal hyperplasia (ADH) in the microdissected formalin-fixed, paraffin-embedded (FFPE) tissues. Forkhead Box M1 (FOXM1), as an oncogenic transcription factor, was predicted as one of the direct targets of miR-671-5p, which was subsequently confirmed by luciferase assays. Forced expression of miR-671-5p in breast cancer cell lines downregulated FOXM1 expression, and attenuated the proliferation and invasion in breast cancer cell lines. Notably, overexpression of miR-671-5p resulted in a shift from epithelial-to-mesenchymal transition (EMT) to mesenchymal-to-epithelial transition (MET) phenotypes in MDA-MB-231 breast cancer cells and induced S-phase arrest. Moreover, miR-671-5p sensitized breast cancer cells to cisplatin, 5-fluorouracil (5-FU) and epirubicin exposure. Host cell reactivation (HCR) assays showed that miR-671-5p reduces DNA repair capability in post-drug exposed breast cancer cells. These data indicates that miR-671-5p functions as a tumor suppressor miRNA by directly targeting FOXM1 in breast cancer. Hence, miR-671-5p may serve as a novel therapeutic target for breast cancer management.

Citation Format: Xiaohui Tan, Yebo Fu, Liang Chen, Shejuan An, Woojin Lee, Yinglei Lai, Katayoon Rezaei, Sana Tabbara, Christine B. Teal, Yan-gao Man, Robert Siegel, Rachel F. Brem, Sidney W. Fu. miR-671-5p promotes epithelial-to-mesenchymal transition by downregulating FOXM1 expression in breast 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 3062. doi:10.1158/1538-7445.AM2015-3062
Abstract 3070: MicroRNA-155 directly targets PDCD4 and activates BIC promoter through AP-1 dependent transcription to replenish miR-155 expression in SAS cells
Authors: zargar shabir A. , Karunagaran Devarajan
Published: August 2015

Pdcd4 (programmed cell death 4) has been demonstrated to be a tumor suppressor gene and is expressed at higher levels during apoptosis. PDCD4 is down regulated in a subset of oral cancers (tongue and buccal cavity) and an association between its down-regulation by miR-21 and tumorigenesis and invasion in oral carcinoma has been demonstrated. In this study we show that miR-155 directly targets PDCD4 in SAS (tongue squamous carcinoma) cells. We demonstrate a positive feedback loop between miR-155 expression and AP-1 dependent transcription through the down regulation of PDCD4. Analysis of miR-155 promoter (BIC) showed the presence of NF-κB and AP-1 (c-Jun and c-Fos) transcription factor binding sites and PDCD4 is known to inhibit AP-1 dependent transcription. Ectopic expression of PDCD4 in SAS cells drastically reduced the BIC promoter activity via inhibition of AP-1 dependent transcription and down regulated the levels of miR-155. We also generated the Lentiviral based miR-155 sponge stable cells to down regulate miR-155 in SAS cells, and found an increase in PDCD4 protein levels. The activity of BIC promoter was relatively low in miR-155 sponge stable cells compared to control sponge stable cells as analyzed by a dual luciferase reporter assay. We have also seen the reduced rate of proliferation in miR-155 sponge stable cells compared to control sponge stable cells. Thus our data show that miR-155 directly targets PDCD4 and consequently activates AP-1 dependent transcription in BIC promoter and increasing the levels of miR-155.

Citation Format: shabir A. zargar, Devarajan Karunagaran. MicroRNA-155 directly targets PDCD4 and activates BIC promoter through AP-1 dependent transcription to replenish miR-155 expression in SAS 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 3070. doi:10.1158/1538-7445.AM2015-3070
Abstract 3071: MicroRNA-486 (miR-486) promotes invasion by targeting RECK in nasopharyngeal carcinoma cells
Authors: Lin Chin-Tarng , Wu Cheng-Der
Published: August 2015

Nasopharyngeal carcinoma (NPC) is a common cancer in Taiwanese and people living in the southeastern region of China. In order to investigate NPC pathogenesis, our laboratory has previously established NPC-TW01 cell line, which was derived from a Taiwanese NPC patient. We also established a NPC-TW01N1 cell line, which was derived from the NPC xenograft in SCID mouse. Both NPC-TW01 and NPC-TW01N1 cell lines have an identical DNA profile (STR). NPC-TW01N1 cell line has higher malignant potency than NPC-TW01 line. For example, the proliferation and invasion capabilities of NPC-TW01N1 line were higher than that of NPC-TW01 line. When we used microRNA microarray to compare the endogenous microRNA expression profiles between NPC-TW01 and NPC-TW01N1 lines, the miR-486, miR-200a and other miRNAs showed higher expression in NPC-TW01N1 cell. Transfection of exogenous miR-486 or anti-miR-486 into NPC-TW01 cells or NPC-TW01N1 cells revealed that miR-486 involves in the regulation of NPC cell progression and invasion. To determine whether miR-486 targeted gene involves in progression and invasion, we analyzed microRNA targeted gene database, Ingenuity pathway databases, and cDNA expression microarrays from miR-486 transfected cells. We found that the RECK gene is one of miR-486 candidate targeted genes that involves in NPC cell progression and invasion. We used pmirGLO luciferase reporter vector assays to demonstrate that miR-486 directly targets RECK 3′ UTR. When we transfected miR-486 or RECK siRNA into NPC cells, we found that they can accelerate tumor progression and invasion. It is concluded that miR-486 and RECK genes maybe potential targets for NPC therapy.

Citation Format: Chin-Tarng Lin, Cheng-Der Wu. MicroRNA-486 (miR-486) promotes invasion by targeting RECK in nasopharyngeal carcinoma 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 3071. doi:10.1158/1538-7445.AM2015-3071
Abstract 3073: Reorganization of metastamiRs in the evolution of metastatic aggressive high-risk neuroblastoma
Authors: Khan Faizan Haider , Ramraj SatishKumar , Aravindan Sheeja , Natarajan Mohan , Herman Terence H. , Aravindan Natarajan
Published: August 2015

MetastamiRs have momentous clinical relevance and have been correlated with disease progression in many tumors. In this study, we identified neuroblastoma metastamiRs exploiting unique mouse models of favorable and high-risk metastatic human neuroblastoma. Further, we related their deregulation to the modulation of target proteins and established their association with clinical outcomes. Whole genome miRNA microarray analysis identified 74 metastamiRs across the manifold of metastatic tumors. RT-qPCR on select miRNAs validated profile expression. Results from bio-informatics across the ingenuity pathway, miRCancer, and literature data-mining endorsed the expression of these miRNAs in multiple tumor systems and showed their role in metastasis, identifying them as metastamiRs. Immunoblotting and TMA-IHC analyses revealed alterations in the expression/phosphorylation of metastamiRs’ targets, including ADAMTS-1, AKT1/2/3, ASK1, AURKβ, Birc1, Birc2, Bric5, β-CATENIN, CASP8, CD54, CDK4, CREB, CTGF, CXCR4, CYCLIN-D1, EGFR, ELK1, ESR1, CFOS, FOSB, FRA, GRB10, GSK3β, IL1α, JUND, kRAS, KRTAP1, MCP1, MEGF10, MMP2, MMP3, MMP9, MMP10, MTA2, MYB, cMYC, NF2, NOS3, P21, pP38, PTPN3, CLEAVED PARP, PKC, SDF-1β, SEMA3D, SELE, STAT3, TLR3, TNFα, TNFR1, and VEGF in aggressive cells ex vivo and in a manifold of metastatic tumors in vivo. Clinical outcome association analysis with the validated metastamiRs’ targets correlated strongly with poor overall and relapse-free survival. For the first time, these results identified a comprehensive list of neuroblastoma metastamiRs, related their deregulation to altered expression of protein targets, and established their association with poor clinical outcomes. The identified set of distinctive neuroblastoma metastamiRs could serve as potential candidates for diagnostic markers for the switch from favorable to high-risk metastatic disease.

Citation Format: Faizan Haider Khan, SatishKumar Ramraj, Sheeja Aravindan, Mohan Natarajan, Terence H. Herman, Natarajan Aravindan. Reorganization of metastamiRs in the evolution of metastatic aggressive high-risk neuroblastoma. [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 3073. doi:10.1158/1538-7445.AM2015-3073
Abstract 3079: Mechanism of hsa-miR-15a in EMT and chemoresistance in colorectal cancer
Authors: Fesler Andrew , Zhai Haiyan , Ju Jingfang
Published: August 2015

Epigenetic alterations such as non-coding microRNAs are critical factors in EMT and chemoresistance. Hsa-miR-15a, as one of the first miRNA identified to be associated with cancer, has been investigated for its role in several types of cancer. We are interested in understanding the molecular and cellular mechanism of hsa-miR-15a in colorectal cancer as hsa-miR-15a is down-regulated in colon cancer and associated with poor patient prognosis. In this study, we have identified several direct key targets of hsa-miR-15a that impact EMT transition, cell cycle and apoptosis. Our results show that the expression of BMI-1, an important regulator of EMT, was suppressed by hsa-miR-15a. The reduction of hsa-miR-15a in colorectal cancer patient samples was significantly inversely correlated with BMI-1 over-expression. Hsa-miR-15a also suppresses the expression of anti-apoptotic protein BCL-2. The suppression of BMI-1, BCL-2 as well as other key targets by hsa-miR-15a has potential for increasing chemosensitivity as well as disrupting cancer stem cell self renewal. In addition, hsa-miR-15a also has potential as a prognostic biomarker in colorectal cancer. This work will provide a further understanding of the mechanism of hsa-miR-15a loss in colorectal cancer and its clinical significance in relationship with its targets and pathways. The functional significance of hsa-miR-15a in regulating key targets and pathways establishes the foundation for hsa-miR-15a as a potential novel therapeutic strategy for treating colorectal cancer.

Citation Format: Andrew Fesler, Haiyan Zhai, Jingfang Ju. Mechanism of hsa-miR-15a in EMT and chemoresistance 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 3079. doi:10.1158/1538-7445.AM2015-3079
Abstract 308: The role of PTEN PDZ-binding domain in mammary gland tumorigenesis
Authors: Yan Mingfei , Or Penelope , Chan Andrew
Published: August 2015

PTEN functions as a key negative regulator of PI3K-Akt pathway through its lipid phosphatase activity. Mutations or loss of PTEN is frequently observed in brain, breast, prostate and endometrial cancer. PTEN also possesses a PDZ-binding domain (PDZ-BD) at its carboxyl terminus, which can be recruited by PDZ-containing proteins like ZO-1 to cell tight junction. Therefore, PTEN may have a potential role in regulating epithelial tight junction integrity. To study the role of PTEN PDZ-BD in breast epithelial tumorigenesis, a PTEN-ΔPDZ mice lacking this domain was generated and further crossed with MMTV-PyMT breast cancer model. As a result, PTENΔPDZ/MMTV-PyMT mice show enhanced tumor growth and metastasis. To elucidate tumor suppressive mechanisms of PTEN PDZ-BD, three-dimensional cultures of PTENΔPDZ mouse mammary epithelial cells (MMEs) was carried out. Though PTEN-ΔPDZ MMEs spheres have normal morphogenesis in 3D culture, they possess larger diameters than wild-type (WT). Besides, both tight junction (ZO-1) and adherent junction (E-Cadherin) of MMEs were examined in 3D culture, though no major differences in cell junction and polarity was observed between PTEN-ΔPDZ and PTEN-WT. Future work will study signaling activities of PTEN-ΔPDZ/MMTV-PyMT breast cancer cells, morphogenesis, polarity and cell junction of PTEN-ΔPDZ/MMTV-PyMT MMEs in 3D cultures.

This work was supported by NIH RO1 (CA133669), Hong Kong Research Grant Council (460713) and Hong Kong PhD Fellowship Scheme (PF12-13584)

Citation Format: Mingfei Yan, Penelope Or, Andrew Chan. The role of PTEN PDZ-binding domain in mammary gland tumorigenesis. [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 308. doi:10.1158/1538-7445.AM2015-308
Abstract 3094: Sprouty and cell proliferation in colorectal cancer
Authors: Zhang Qiong , Shim Katherine , Wright Kevin , Jurkevich Alexander , Khare Sharad
Published: August 2015

BACKGROUND & AIMS: Sprouty (SPRY) proteins are evolutionarily conserved modulators of mitogen-activated protein kinase pathway. SPRY2 appears to function as a tumor suppressor in other cancers, whereas we reported that SPRY2 functions as an oncogene in colorectal cancer (CRC). To further understand the oncogenic potential of SPRY1 and SPRY2 in CRC, we investigated the mechanisms by which these proteins regulate cell proliferation in CRC. MATERIALS & METHODS: Human CRC cDNA arrays were employed to assess mRNA levels of SPRY1, SPRY2 and p21. SPRY1 and SPRY2 were knocked-down in CaCo2 colon cancer cells by siRNA. Effects of SPRY were assessed by immunoblotting, real time PCR, luciferase reporter assay, and confocal microscopy. Mouse embryonic fibroblasts (MEFs) derived from SPRY mutant mice were utilized to dissect SPRY functions in mesenchymal cells. RESULTS: In this study, surprisingly, we present evidence to suggest that concomitant activation of ERK, p-38 and AKT signaling cascades is insufficient to drive cancer cell proliferation in SPRY modulated cells. Suppression of SPRY in colon cancer cells upregulates p21, a cell cycle inhibitor. SPRY2 dependent p21 promoter activation may account for upregulation of p21 expression and inhibition of cancer cell proliferation. Underscoring the biological relevance of these findings, recombination of floxed SPRY1 and SPRY2 alleles in mouse embryonic fibroblasts (MEFs) resulted in increased expression of p21. Finally, in a human CRC cDNA array we established an inverse correlation of SPRY1 and SPRY2 with p21 mRNA expression. CONCLUSIONS: Together, this study indicates that SPRY is a target of therapeutic intervention in CRC.

Citation Format: Qiong Zhang, Katherine Shim, Kevin Wright, Alexander Jurkevich, Sharad Khare. Sprouty and cell proliferation 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 3094. doi:10.1158/1538-7445.AM2015-3094
Abstract 3102: AZD1152HQPA Accurin™ nanoparticles inhibit growth of diffuse large B-cell lymphomas and small cell lung cancer
Authors: Ashton Susan , Taylor Paula , Curtis Nicola , Pilling James , Dorval Thierry , Hrkach Jeff , Jewsbury Philip J. , Barry Simon T.
Published: August 2015

Inhibitors of the Aurora Kinases have been developed to treat both liquid and solid tumours. The prodrug AZD1152 is an inhibitor of Aurora kinase B that is clinically active in acute myeloid leukaemia. Despite this clinical proof-of-concept, the broader clinical utility of AZD1152 is limited by the requirement for continuous IV infusion, and the mechanism-related dose-limiting toxicities seen with this class of inhibitors, in particular bone marrow toxicity.   To address these challenges and maximise the clinical utility, an Accurin nanoparticle containing AZD1152HQPA, the active metabolite of AZD1152, has been developed. In preclinical models, the AZD1152HQPA Accurin shows increased efficacy without the bone marrow toxicity seen with the prodrug formulation.  In preclinical studies, models of Diffuse Large B Cell Lymphoma (DLBCL) and Small Cell Lung Cancer (SCLC) show sensitivity to monotherapy Aurora B kinase inhibitors.  Consistent with this, AZD1152 inhibits the growth of subsets of DLBCL and SCLC cells lines in vitro, while in vivo, AZD1152HQPA Accurin consistently reduces the growth of DLBCL and SCLC models.  When given at 25mg/kg on days 1 and 3, AZD1152HQPA Accurin gave either equivalent or superior activity to AZD1152 delivered at 25mg/kg on days 1, 2, 3 and 4. When the dose-schedule was explored, increasing the dose intensity increases the anti-tumour effect, while modifying the timing and dose intensity of each dose cycle also influenced the anti-tumour activity. In a DLBCL model, low dose AZD1152HQPA Accurin (25mg/kg delivered as a fractionated dose on day 1 and 3) gave tumour stasis or partial regression, while a higher dose (50mg/kg delivered weekly) gave increased tumour response, which was durable on repeated dosing. The timing of AZD1152HQPA Accurin doses had significant impact on the shape of the tumour response, indicating that optimal scheduling is important to maximize the benefits of sustained release and enhanced tumour accumulation of Accurin nanoparticles. Collectively the preclinical data indicate that the AZD1152HQPA Accurin has the potential for activity in SCLC and DLBCL; is able to be used flexibly; and has an improved therapeutic index.

Citation Format: Susan Ashton, Paula Taylor, Nicola Curtis, James Pilling, Thierry Dorval, Jeff Hrkach, Philip J. Jewsbury, Simon T. Barry. AZD1152HQPA Accurin™ nanoparticles inhibit growth of diffuse large B-cell lymphomas and small cell 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 3102. doi:10.1158/1538-7445.AM2015-3102
Abstract 3109: A functional microRNA screening approach that identifies microRNAs affecting melanoma cell invasion
Authors: Weber Claudia E.M. , Luo Chonglin , Hotz-Wagenblatt Agnes , Osen Wolfram , Holland-Letz Tim , Eichmüller Stefan B.
Published: August 2015

Melanoma is a fast progressing tumor which tends to metastasize at small size and at early time point. miRNA profiling has been performed for a variety of cancer types, however, the results obtained differ substantially among published studies. Therefore, it is of major interest to unravel miRNA networks involved in melanoma progression as, for example, in tumor cell invasion. In order to follow this aim, we established a functional screening approach based on a high-throughput invasion assay using a human miRNA mimics library consisting of 988 miRNAs (miRBase Version 13.0). Applying this strategy, we could identify miRNAs that enhanced the invasive capacity of A375 melanoma cells (oncogenic miRNAs), as well as miRNAs with a lowering effect on invasiveness, latters found predominantly down-regulated in melanoma and thus considered as tumor-suppressors. miR-339-3p was one of the promising candidates which inhibited invasion when transfected into different melanoma cell lines. In addition, miR-339-3p expression was significantly decreased in melanoma cell lines compared to normal human melanocytes. Furthermore, the myeloid leukemia cell differentiation protein (MCL-1) was identified as a novel target of miR-339-3p and found to be down-regulated by miR-339-3p both on protein and on mRNA level. MCL1 down-regulation by siRNA could mimic inhibited invasion as observed after miR-339-3p transfection. Our findings indicate that miR-339-3p can act as a tumor suppressor in melanoma and its expression might contribute to the varying degrees of aggressiveness among different melanomas. We believe that our approach can unravel possible therapeutics checkpoints which might be used therapeutically, to counteract tumor spread.

Citation Format: Claudia E.M. Weber, Chonglin Luo, Agnes Hotz-Wagenblatt, Wolfram Osen, Tim Holland-Letz, Stefan B. Eichmüller. A functional microRNA screening approach that identifies microRNAs affecting melanoma cell invasion. [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 3109. doi:10.1158/1538-7445.AM2015-3109
Abstract 3115: miR-30a-5p functions as a tumor suppressor gene in gastric cancer
Authors: Min Jimin , Han Tae-su , Choi Boram , Hur Keun , Lee Hyuk-Joon , Yang Han-Kwang
Published: August 2015

Gastric cancer (GC) is the second leading cause of cancer-related death. MicroRNAs(miRNAs) are an abundant class of negative gene regulator and regulate multiple gene targets. miRNAs control a wide range of biological functions such as cellular proliferation, differentiation and apoptosis. Moreover, many miRNAs are highly conserved, and their deregulation is often associated with human malignancies. The aims of this study are to determine the miR-30a functions as a tumor suppressor gene and to evaluate whether the miR-30a-5p is able to use the diagnostic or prognostic marker in GC. To identify the gastric tumor-associated miRNAs, miRNA microarray was performed using the gastric cancer tissues. Among them, miR-30a-5p was down-regulated in GC tissues compared to normal mucosa. qRT-PCR was employed to confirm the microarray results. MiR-30a-5p expression was frequently down-regulated in our GC cohort, (n = 55, P<0.0001). To determine the miR-30a-5p biological functions in GC, miR-30a-5p mimic or inhibitor was treated in GC cell lines. Ectopic expression of miR-30a-5p decreased cell growth, migration capacity and colony formation in vitro. Some previous studies have elucidated that miR-30a-5p is associated with metastasis in some cancer types. Accordingly, we confirmed its expression in our GC cohort with lymph node metastasis (n = 13) using qRT-PCR. MiR-30a-5p was significantly down-regulated in lymph node metastasis tissues than normal or tumor tissues. Taken together, the miR-30a-5p expression was frequently down-regulated in GC and lymph node metastasis. In addition, the miR-30a-5p suppressed tumorigenesis. Therefore, we suggest that miR-30a-5p activation may be a useful strategy of GC patient therapy and it can serve as a diagnostic or prognostic marker for GC.

Citation Format: Jimin Min, Tae-su Han, Boram Choi, Keun Hur, Hyuk-Joon Lee, Han-Kwang Yang. miR-30a-5p functions as a tumor suppressor gene in gastric 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 3115. doi:10.1158/1538-7445.AM2015-3115
Abstract 3123: miR-520b inhibits malignancy of head-neck cancer through suppression of cancer stemness by targeting to CD44 molecule
Authors: Lu Ya-Ching , Cheng Ann-Joy
Published: August 2015

MicroRNAs (miRNAs) have been implicated playing important role in regulating malignant progression of cancer. Here, we characterized the functional effects and regulatory mechanism of miR-520b in head-neck cancer (HNC). Without affecting cell growth, exogenous transduction of miR-520b into HNC cell lines significantly increased sensitivity to the therapeutic drug and radiation treatment, indicating that miR-520b possesses pro-apoptotic function. Transduction of miR-520b also decreased cell adhesion and mobile ability, accompanying with the reversion of epithelial- mesenchymal transition. Significantly, miR-520b suppressed the conversion of cancer stem cell (CSC) as demonstrated by reduced expressions of stemness markers (nestin and CD44), inhibiting sphenoid cell formation, and inhibiting pluripotent stemness regulators (Twist, Nanog and Oct4). Furthermore, CD44 was identified the direct target of miR-520b, which was shown by the response to miR-520b modulation via either exogenous or antigomir transduction. Functional analyses also confirmed this regulatory mechanism. The altered cell mobility and sphenoid forming ability by miR-520b modulation were rescued upon CD44 silencing. The miR-520b induced stemness regulators were also inhibited when simultaneously silencing CD44. Study in xenografted mice showed that miR-520b knockdown led to an acceleration of tumorigenesis. Reversely, miR-520b transduction dramatically restrained tumor growth, along with the inhibition of stem cell regulatory proteins. Taken together, our finding demonstrated that miR-520b inhibits malignancy of HNC through regulation of cancer stemness by targeting to CD44 molecule. Our finding provides molecular mechanism of miR-520b in HNC, which may also yield insights as novel targeting therapeutic strategy for HNC.

Citation Format: Ya-Ching Lu, Ann-Joy Cheng. miR-520b inhibits malignancy of head-neck cancer through suppression of cancer stemness by targeting to CD44 molecule. [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 3123. doi:10.1158/1538-7445.AM2015-3123
Abstract 3126: Survival in glioblastoma cancer patients is predicted by miR-340, that regulates key cancer hallmarks by inhibiting NRAS
Authors: Fiore Danilo , Quintavalle Cristina , Donnarumma Elvira , Roscigno Giuseppina , Iaboni Margherita , Russo Valentina , Adamo Assunta , De Martino Fabio , Greco Adelaide , Romano Giulia , Ylermi Soini , Brunetti Arturo , Croce Carlo Maria , Condorelli Gerolama
Published: August 2015

Glioblastoma is the most frequent brain tumor in adults and is the most lethal form of human cancer. Despite the improvements in treatments, patients survival remains poor. Nevertheless, a subset of patients survives longer than 3 years and they are classified as long-term survivors (LTS). The molecular and cellular mechanisms underlying the rare phenomenon of LTS are not well known. MicroRNAs (miRNAs or miRs) are a class of endogenous non-coding RNA of 19-24 nucleotides in length that have an important role in the negative regulation of gene expression. Deregulation of miRNAs is linked to the pathogenesis of many types of cancer. We performed a nanostring miRNA analysis on long and short glioblastoma survivors patients to individuate miRs potentially involved in LTS phenotype. Using this approach, we identified miR-340 as a novel tumor-suppressor-miR in glioblastoma. miR-340 expression was increased in LTS compared to short term survivors. Moreover, a log-rank test analysis on both the data collected from TCGA database and from a cohort of glioblastoma patients present in our lab revealed that low levels of miR-340 were a risk indicator for glioblastoma patients survival. miR-340 overexpression decreased cell proliferation, anchorage independent cell growth, cell cycle and response to temozolomide in different glioblastoma cell lines. We identified NRAS as a direct target of miR-340. Rescue experiments showed its essential role in mediating the onco-suppressive activity of miR-340. The overexpression of miR-340 decreased the activation of ERKs and AKT, the main pathways downstream NRAS. Furthermore, glioblastoma cells stably infected with a lentivirus encoding miR-340 exhibited a drastic reduction of tumor growth in nude mice. In conclusion, our findings reveal miR-340 as a new tumor-suppressor miRNA up-regulated in LTS in glioblastoma. Its expression inversely correlates with survival of glioblastoma patients. miR-340 is able to regulate multiple tumorigenic features of glioblastoma cells, offering a novel potential prognostic and therapeutical target for glioblastoma.

Citation Format: Danilo Fiore, Cristina Quintavalle, Elvira Donnarumma, Giuseppina Roscigno, Margherita Iaboni, Valentina Russo, Assunta Adamo, Fabio De Martino, Adelaide Greco, Giulia Romano, Soini Ylermi, Arturo Brunetti, Carlo Maria Croce, Gerolama Condorelli. Survival in glioblastoma cancer patients is predicted by miR-340, that regulates key cancer hallmarks by inhibiting NRAS. [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 3126. doi:10.1158/1538-7445.AM2015-3126
Abstract 3136: Adoptive transfer of bone marrow T cells induces antitumor immune responses in murine models of melanoma and neuroblastoma
Authors: Kodumudi Krithika N. , Weber Amy , Moore Ellen , Sarnaik Amod , Pilon-Thomas Shari
Published: August 2015

Bone marrow (BM) serves as a reservoir for a unique population of memory T cells. Tumor-specific T cells have been identified in the bone marrow of cancer patients. However, few direct functional analyses of tumor-specific responses in T cells isolated from BM have been performed. In this study, we investigated the ability of bone marrow T cells to induce anti-tumor immunity in mice bearing neuro2A neuroblastoma or B16 melanoma. To demonstrate the presence of antigen-specific T cells in BM, we first examined the percent of antigen-specific CD8+ T cells in vaccinated mice. The overall percent of antigen-specific CD8+ T cells was much higher in BM compared to spleen and lymph nodes of vaccinated mice. To investigate the ability of antigen-specific BM T cells to induce cytotoxic function, BM T cells were isolated from mice vaccinated with OVASIINFEKL peptide pulsed dendritic cells (DC). Expanded BM T cells from DC vaccinated mice co-cultured with M05 or irrelevant tumor cells led to tumor-specific cytotoxicity (p<0.001). In B16 tumor-bearing mice, T cells isolated from BM produced IFN-gamma in response to gp100 peptide (1400+210 pg/ml). Adoptive transfer of BM T cells isolated from B16-bearing mice led to a delay in tumor growth compared to control groups (p<0.001). In the neuroblastoma model, T cells isolated from BM of neuro2A-bearing mice produced higher levels of IFN-gamma and were tumor-specific (250+90 pg/ml, p<0.01 compared to T cells cultured with irrelevant tumor cells). Adoptive transfer of expanded BM T cells and DC vaccination in the setting of BM transplant led to a significant delay in tumor growth and enhanced survival in neuro2A bearing mice compared to BM transplant + DC vaccination alone group (p<0.02). These studies demonstrate that tumor-specific T cells can be isolated from the BM of tumor-bearing mice. Adoptive transfer of T cells expanded from the BM can delay tumor growth and improve survival. These studies support the isolation and expansion of T cells from the BM for use in adoptive cell therapy strategies in patients with neuroblastoma and melanoma.

Citation Format: Krithika N. Kodumudi, Amy Weber, Ellen Moore, Amod Sarnaik, Shari Pilon-Thomas. Adoptive transfer of bone marrow T cells induces antitumor immune responses in murine models of melanoma and neuroblastoma. [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 3136. doi:10.1158/1538-7445.AM2015-3136
Abstract 3170: IL17 favours carcinogenesis and limits the anti-tumor responses in pancreatic cancer
Authors: Cappello Paola , Curto Roberta , Mucciolo Gianluca , Rolla Simona , Tonoli Elisabetta , Novelli Francesco
Published: August 2015

Pancreatic ductal adenocarcinoma (PDA) is a fatal medical condition with few advances in therapy and patient survival. The role of IL17 and Th17 in cancer progression and anti-tumor immunity is still controversial. In this study we have investigated the role of IL17 and Th17 in PDA carcinogenesis and anti-tumor responses.

IL-17 production and Th17 percentage in blood from PDA patients and control subjects as well from genetically engineered mice (GEM) that spontaneously develop PDA, were analysed by ELISA and FACS respectively. Survival of GEM mice crossed with IL-17 KO mice (GEM/IL17KO) was analysed by Kaplan-Meier analysis. WT or IL17KO mice that were prophylactically vaccinated with a plasmid coding for the PDA-associated antigen α-enolase (ENO1) (1-3), were subsequently injected with PDA cell line derived from GEM. Tumor growth and the induction of an antigen-specific immune response were monitored.

We have found a statistically significant increase of peripheral Th17 cells and a decrease of Th1 in PDA patients compared to healthy subjects. GEM mice showed 3-fold more RORγT+ cells at the onset of duct transformation, which dropped to the level of control mice at 20 weeks and lasted until 35 weeks. Notably, GEM/IL17 KO mice survived significantly more than GEM mice, even if there were no changes in the tumor onset. In addition, in GEM/IL17 KO mice, we observed an increased fibrotic reaction compared to GEM mice starting from early stage of disease. Lastly, ENO-1 DNA vaccination in IL17KO mice significantly decreased PDA cells growth and enhanced the CD8 T cell response compared to that observed in WT mice.

Our data suggest that the absence of IL17 does not affect the tumor onset but the progression, likely affecting the immune response, which seems to be able to better counteract tumor growth in the absence of this cytokine.

Tomaino et al., J Proteome Res. 2007;6:4025-31; Cappello et al, Int. J. Cancer. 2009;125:639-48; Cappello P et al, Gastroenterology. 2013;144:1098-106.

Citation Format: Paola Cappello, Roberta Curto, Gianluca Mucciolo, Simona Rolla, Elisabetta Tonoli, Francesco Novelli. IL17 favours carcinogenesis and limits the anti-tumor responses in pancreatic 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 3170. doi:10.1158/1538-7445.AM2015-3170