bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 2445: Cytoplasmic mislocalization of p27 promotes metastasis and its autoantibody correlates with prognosis in osteosarcoma
Authors: Nakka Manjula , Li Yiting , Kelly Aaron J. , Lau Ching C. , Krailo Mark , Barkauskas Donald A. , Hicks John , Man Tsz-Kwong
Published: July 2016

Development of metastasis is the major cause of death in osteosarcoma, which is the most common malignant bone tumor in children and young adults. However, detection of metastasis relies solely on imaging techniques and targeted treatments of metastatic patients are still not available to improve the dismal outcome. Using an immunoproteomic approach, we identified that p27 autoantibody was significantly elevated in the plasma of high-risk osteosarcoma patients. Results of immunohistochemistry showed that cytoplasmic mislocalization of p27 occurred in a majority of osteosarcoma cases and in highly metastatic osteosarcoma cell lines. We demonstrated that ectopic expression of cytoplasmic p27 and shRNA-mediated gene silencing promoted and inhibited, respectively, the migration and invasion of osteosarcoma cells. Additionally, a mutation in S10 or T198, but not T157, phosphosite abolished the pro-migration and invasion phenotypes of cytoplasmic p27, possibly through a RhoA-related mechanism. Furthermore, mice injected with cells carrying cytoplasmic p27 increased the development of pulmonary metastasis when compared to an empty vector control. Lastly, using a large cohort of serum samples (n = 233), we showed that a higher level of the p27 autoantibody significantly correlated with poor overall and event-free survival of osteosarcoma (p < 0.05). Together, our results suggest that the circulating p27 autoantibody can be used as a prognostic biomarker at diagnosis and cytoplasmic mislocalization of p27 is a frequent event in osteosarcoma, which can promote tumor cell motility and invasiveness as well as metastasis formation. Targeting specific p27 phosphorylations may provide a novel therapeutic approach for osteosarcoma patients with metastasis.

Citation Format: Manjula Nakka, Yiting Li, Aaron J. Kelly, Ching C. Lau, Mark Krailo, Donald A. Barkauskas, John Hicks, Tsz-Kwong Man. Cytoplasmic mislocalization of p27 promotes metastasis and its autoantibody correlates with prognosis in osteosarcoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2445.
Abstract 2449: Hedgehog pathway inhibition sensitizes embryonal rhabdomyosarcoma to standard chemotherapy
Authors: Manzella Gabriele , Kottarathil Tina , Schaefer Beat W.
Published: July 2016

Hedgehog (Hh) is one of the key pathways orchestrating embryonic development as well as regulating homeostasis of postnatal organs. Perturbation of Hh signaling activity is associated with the onset of different childhood cancer entities such as embryonal rhabdomyosarcoma (eRMS). According to this, previous findings from our laboratory revealed that the tumor initiating populations (TIPs) of eRMS retain high activity of the pathway, which boosts their tumorigenic potential and self-renewal ability. Moreover, TIPs are well known to be responsible for seeding recurrent tumors following standard chemotherapy. This phenomenon might explain the failure of cytotoxic drugs in high-risk eRMS patients for whom conventional therapeutic approaches remain inadequate.

Therefore, in this study we investigated the role of Hh pathway in the context of chemoresistance. We established several patient-derived xenograft (PDX) models and primary cells derived from diagnostic and relapsed tumor specimens. Histological and immunofluorescence analysis confirmed that both cellular and patient heterogeneity were preserved in our cohort. Interestingly, we found that Hh target genes were significantly upregulated in chemoresistant PDX tumors and demonstrated that the use of Hh antagonists could significantly sensitize eRMS cells toward debulking drugs such as doxorubicin, actinomycin and vincristine. Ongoing experiments aim at confirming these results in cells with selective knock- out of components of Hh pathway as well as at elucidating if chemotherapy might induce a selection of resistant clones or a transition of sensitive cancer cells toward a resistant phenotype with high Hh pathway activity.

In conclusion, our data indicate that inhibition of Hh signaling might represent a promising strategy to enhance the therapeutic window of standard cytotoxic agents.

Citation Format: Gabriele Manzella, Tina Kottarathil, Beat W. Schaefer. Hedgehog pathway inhibition sensitizes embryonal rhabdomyosarcoma to standard chemotherapy. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2449.
Abstract 2450: MYCN and TFAP4 promote neuroblastoma malignancy by cooperating in the regulation a subset of target genes involved in cancer cell growth and metastasis
Authors: Xue Chengyuan , Yu Denise M. , Gherardi Samuele , Koach Jessica , Milazzo Giorgio , Gamble Laura , Liu Bing , Russell Amanda , Liu Tao , Cheung Belamy B. , Marshall Glenn M. , Perini Giovanni , Haber Michelle , Norris Murray D.
Published: July 2016

Amplification of the MYCN oncogene, a member of the MYC family of transcriptional regulators, is one of the most powerful prognostic markers identified for poor outcome in neuroblastoma, the most common extracranial solid cancer in childhood. While MYCN has been established as a key driver of malignancy in neuroblastoma, the underlying molecular mechanisms are poorly understood. Transcription factor activating enhancer binding protein-4 (TFAP4), which plays important roles in cancer progression, has been reported to be a direct transcriptional target of MYC. In this study, we have shown that high expression of TFAP4 in primary neuroblastoma patients is associated with poor clinical outcome and furthermore that siRNA-mediated suppression of TFAP4 in MYCN-expressing neuroblastoma cells impaired migration and colony formation, and led to an increased proportion of cells in G1/S phase of the cell cycle. Chromatin immunoprecipitation and luciferase reporter assays demonstrated that TFAP4 expression is positively regulated by MYCN through direct promoter binding. In addition, when MYCN was overexpressed in neuroblastoma cells, TFAP4 was required for the observed increase in cell migration. Microarray analysis identified genes regulated by both MYCN and TFAP4 in neuroblastoma cells, including Phosphoribosyl-pyrophosphate synthetase-2 (PRPS2) and Syndecan-1 (SDC1), which are involved in cancer cell proliferation and metastasis. Overall this study unveils a complex regulatory circuit in which MYCN by elevating TFAP4 expression, cooperates with it to control a specific set of genes involved in tumor progression. These findings highlight the existence of a MYCN-TFAP4 axis in MYCN-driven neuroblastoma as well as identifying relevant therapeutic targets for aggressive forms of this disease.

Citation Format: Chengyuan Xue, Denise M. Yu, Samuele Gherardi, Jessica Koach, Giorgio Milazzo, Laura Gamble, Bing Liu, Amanda Russell, Tao Liu, Belamy B. Cheung, Glenn M. Marshall, Giovanni Perini, Michelle Haber, Murray D. Norris. MYCN and TFAP4 promote neuroblastoma malignancy by cooperating in the regulation a subset of target genes involved in cancer cell growth and metastasis. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2450.
Abstract 2506: Citral reduces breast tumor growth by inhibiting cancer stem cell marker ALDH1A3
Authors: Thomas Margaret L. , De Antueno Roberto , Coyle Krysta , Cruickshank Brianne , Giacomantonio Michael , Duncan Roy , Giacomantonio Carman , Marcato Paola
Published: July 2016

Breast cancer stem cells (CSCs) can be identified by increased Aldefluor activity which is primarily due to aldehyde dehydrogenase 1A3 (ALDH1A3) expression. In addition to being a CSC marker, ALDH1A3 regulates genes expression via inducing retinoic acid (RA) signaling and plays an important role in mediating progression of cancers, including breast, melanoma, lung and glioblastoma. Therefore, ALDH1A3 represents a novel druggable anti-cancer target of interest. There are no currently characterized inhibitors of the ALDH1A3 isoform, so twelve general ALDH inhibitors were tested for their effectiveness in targeting ALDH1A3 activity. Ability to directly inhibit ALDH activity was quantified with the Aldefluor assay on a patient tumor xenograft and on breast cancer cell lines with known ALDH isoform activity. Inhibition of RA signaling was quantified by measuring expression of the RA-inducible genes RARRES1 and RARβ. To investigate the anti-cancer properties of these compounds, apoptosis was quantified with the annexin V assay. Citral significantly reduced ALDH1A3- and ALDH2-associated Aldefluor activity in breast cancer cell lines and also reduced Aldefluor activity of a patient-derived xenograft. Citral reduced expression of RA-inducible genes through reducing ALDH1A3 activity. Citral induced apoptosis in vitro in an ALDH-independent manner in breast cancer cell lines and reduced proliferation in the MDA-MB-231 breast cancer cell line. Nanoparticle (NP)-encapsulated citral was generated for in vivo use and administered intravenously to female NOD/SCID mice harbouring MDA-MB-231 ALDH1A3-overexpression tumors. 10mg/kg NP-citral significantly decreased the growth of ALDH1A3-driven MDA-MB-231 tumors. Nanoparticle-encapsulated citral shows promise as an adjuvant therapy for patients with tumors that have a large population of high-ALDH1A3 CSCs.

Citation Format: Margaret L. Thomas, Roberto De Antueno, Krysta Coyle, Brianne Cruickshank, Michael Giacomantonio, Roy Duncan, Carman Giacomantonio, Paola Marcato. Citral reduces breast tumor growth by inhibiting cancer stem cell marker ALDH1A3. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2506.
Abstract 2508: A red-shifted fluorescent substrate for aldehyde dehydrogenase, AldeRed 588-A, for labeling viable ALDH-positive cells
Authors: Asbrock Nick , Chu Vi , Pomper Martin
Published: July 2016

Normal and cancer stem cells can be isolated based upon the enzymatic activity of aldehyde dehydrogenase I (ALDH1), a detoxifying enzyme responsible for oxidation of hazardous aldehyde byproducts. ALDH1 has been used to isolate cancer stem cells from various human malignancies including bladder, breast, cervical, colon, head and neck, liver, lung, pancreas, prostate and ovary. Currently, the ALDEFLUOR assay, is the only commercially available reagent for ALDH detection in live cells. The substrate used in this assay primarily emits in the green region of the electromagnetic spectrum (512nm). For researchers with valuable cell and transgenic animal models in which the target gene of interest has been tagged with eGFP, ALDEFLUOR therefore cannot be used. Selection of cells positive for aldehyde dehydrogenase (ALDH) activity from a green fluorescent background is thus difficult with existing reagents. We now describe a red-shifted fluorescent substrate for ALDH, AldeRed 588-A, that provides additional flexibility for utilizing ALDH as a marker for stem cell and cancer stem cell isolation. The activity of AldeRed 588-A was compared with the ALDEFLUOR reagent and demonstrated similar ability to fractionate ALDHpos cells in a number of cell lines tested.

Citation Format: Nick Asbrock, Vi Chu, Martin Pomper. A red-shifted fluorescent substrate for aldehyde dehydrogenase, AldeRed 588-A, for labeling viable ALDH-positive cells. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2508.
Abstract 2516: TRIM8 modulates stem-like cells in glioblastoma
Authors: Zhang Changming , Subhas Mukherjee , Carol Tucker-Burden , Chau Monica , Kong Jun , Brat Daniel
Published: July 2016

Glioblastoma stem-like cells (GSC) contribute to rapid growth and clinical recurrence of these fatal tumors and are highly resistant to therapy. STAT3 is known to contribute to maintenance and proliferation of GSC. Here we report a novel protein known as Tri-partite Motif containing protein 8 (TRIM8) that modifies tumor growth through STAT3. TRIM8, previously referred to as “glioblastoma expressed ring finger protein” is expressed at equal levels in glioblastoma and normal brain samples, despite showing hemizygous deletion in 87% of cases in TCGA data. To uncover mechanisms, we knocked down TRIM8 in glioblastoma-derived neurospheres using sh-RNA and found that this reduced the levels of phosphorylated STAT3 (p-STAT3), C-MYC and SOX2. Overexpression of TRIM8 resulted in higher expression of p-STAT3, C-MYC, SOX2 and CD133. We also found that specifically blocking STAT3 in neurospheres by pharmacological inhibition reduced the expression of TRIM8. Conversely, upregulation of STAT3 induced by IL-6 results in increased expression of TRIM8. Together, our results indicate that TRIM8 could potentially regulate GSC by forming a positive feedback loop with STAT3.

Citation Format: Changming Zhang, Mukherjee Subhas, Tucker-Burden Carol, Monica Chau, Jun Kong, Daniel Brat. TRIM8 modulates stem-like cells in glioblastoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2516.
Abstract 2519: A novel role for brachyury as a key regulator of sonic hedgehog signaling (Shh) and maintenance of stemness in gliomas
Authors: Kesanakurti Divya , Canella Alessandro , Xu Jihong , Puduvalli Vinay K.
Published: July 2016

Glioblastomas are the most common and aggressive form of adult primary brain tumors and are associated with a dismal prognosis. Accumulating evidences suggest that a subset of therapy-resistant cancer stem cells are responsible for recurrence in tumors targeting which may help in gliomas. We identified a significant overexpression of Brachyury (T-box transcription factor) in correlation with glioma histological grade when compared to non-tumor brain controls, with the highest expression being in grade IV gliomas. We also observed increased expression of Brachyury in several glioma cell lines and stem cells (GSCs) when compared to normal human astrocytes. Serum-induced differentiation of GSCs resulted in loss of Brachyury expression along with decreased stem-cell marker levels in these cells, which prompted us to study the potential role of Brachyury in glioma stemness and to delineate the underlying signaling mechanisms. Specific shRNA-mediated knockdown of Brachyury significantly decreased proliferation, migration and invasion in glioma cell lines. Brachyury suppression led to inhibition of sphere formation of GSCs and decreased stem cells marker expression including CD133, nestin and Nanog. Brachyury knockdown also inhibited the activation of sonic hedgehog (Shh) signaling and decreased Gli1 levels in these cells. On the other hand, stable overexpression of Brachyury resulted in the activation of Shh pathway and elevated stem cell marker expression in GSCs. Based on these in vitro findings, our future studies will be focused on determining the role of Brachyury in orthotopic tumor growth in vivo. In summary, our data reveals a novel role for Brachyury in the regulation of tumor invasiveness and stemness, and indicates a potential for therapeutic targeting of Brachyury in patients with gliomas.

Citation Format: Divya Kesanakurti, Alessandro Canella, Jihong Xu, Vinay K. Puduvalli. A novel role for brachyury as a key regulator of sonic hedgehog signaling (Shh) and maintenance of stemness in gliomas. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2519.
Abstract 2522: S100A4 is a critical regulator of stemness and the mesenchymal phenotype in GBMs
Authors: Chow KIn-Hoe , Park Hee Jung , George Joshy , Gallup Andrew D. , Neilson Eric , Yun Kyuson
Published: July 2016

Glioblastoma (GBM) is one of the most incurable human cancers, and the mesenchymal subtype of GBMs has the worst prognosis. The mesenchymal phenotype and glioma stem cells (GSCs) are associated with tumor recurrence and therapy resistance. While growing evidence suggests that tumor microenvironment modulates stemness and the mesenchymal phenotype, little is known about how these phenotypes are coordinately regulated. Here we report that S100A4 is a critical regulator of stemness and the mesenchymal phenotype in GBMs. First, we show that S100a4 is a novel marker and a regulator of GBM TICs. Using genetically engineered mice and patient derived GBM tumorspheres, we show that S100a4 expression is enriched in TICs and that S100a4 function is critical for self-renewal of these cells. Furthermore, we demonstrate that selective ablation of S100a4+ cells in vivo is sufficient to block tumor growth. Second, we show that S100A4 regulates expression of EMT regulators, SNAIL2 and ZEB1, in addition to master transcriptional regulators of the mesenchymal signature genes (CEBPB/D, RUNX1, FOSL2, and BHLHE40), suggesting that S100A4 is an upstream (master) regulator of mesenchymal transition in GBMs. Third, we show that acidosis, a common environmental stress in malignant tumors, induces S100A4 and epithelial-mesenchymal transition (EMT) regulator expression. Importantly, S100A4 is required for acidosis-induced EMT and mesenchymal transition. Consistently, S100A4 expression is strongly associated with the mesenchymal subtype of GBMs, and S100A4 is an independent prognostic indicator for the mesenchymal subtype GBM patient survival. In summary, we show that S100A4 is a critical node in the molecular network that controls glioma stem cells and the mesenchymal phenotype, and propose that targeting S100A4 may simultaneously suppress mesenchymal transition and stemness of glioma cells, particularly in stressful tumor environments.

Citation Format: KIn-Hoe Chow, Hee Jung Park, Joshy George, Andrew D. Gallup, Eric Neilson, Kyuson Yun. S100A4 is a critical regulator of stemness and the mesenchymal phenotype in GBMs. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2522.
Abstract 2532: Alginate-based 3D system for the enrichment and culture of cancer stem cells
Authors: Simon Karen A. , Murikipudi Sylaja , Rogoff Harry A. , Li Chiang J.
Published: July 2016

Cancer stem cells (CSCs)—cancer cells which have the ability to undergo “self-renewal” are considered to be responsible for the recurrence and metastasis of tumors. The development of a culture system which can mimic aspects of the tumor microenvironment within the cancer stem cell niche is important to elucidate the mechanisms that underlie the growth and survival of CSCs and to identify compounds that can target and eliminate this highly malignant cell population.

Here we demonstrate the use of an alginate-based 3D cell culture as an in vitro system for enriching and maintaining the stemness properties of cancer cell lines. In this work, we used alginate gels as a three-dimensional (3D) matrix to culture cancer cell lines. Alginate is an ideal system for CSC because of its inertness and ability to provide a hypoxic environment essential for maintaining the stem-like properties of these cells. We found that cells cultured in the alginate 3D matrix have increased CSC-related gene expression and alterations in metabolic-related gene expression that are consistent with changes reported to occur in CSC that help them to maintain their drug resistant and invasive properties.

In order to be useful as a drug screening platform to identify CSC targeting agents, we verified that the high stemness characteristics of the cells cultured in the alginate 3D matrix can be maintained over multiple passages and many months of continuous culture. The CSC cultures in the alginate 3D matrix were found to be resistant to both conventional chemotherapy and targeted therapeutics, while remaining sensitive to CSC targeting agents BB608 and BB503. These results support the potential of the alginate 3D culture system in the enrichment and expansion of CSCs, and provide a reliable in vitro system for the development and evaluation of CSC-targeting agents.

Citation Format: Karen A. Simon, Sylaja Murikipudi, Harry A. Rogoff, Chiang J. Li. Alginate-based 3D system for the enrichment and culture of cancer stem cells. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2532.
Abstract 2536: AP-1/Fra-1 as a target for therapy promotes chemoradiosensitivity of cancer and cancer stem cells
Authors: Das Bhudev C. , Tyagi Abhishek , Roy Bal Gangadhar , Bharti Alok C.
Published: July 2016

Transcription factor activator protein-1 (AP-1) super-family is known to modulate expression of array of genes during development of many cancers. It is also an indispensable factor for efficient expression of high risk HPV oncogenes E6/E7. Recent studies demonstrated the role of AP-1 in promoting stemness/quiescence of cancer stem cells. We have recently reported that HPVE6 oncogene controls stemness and self-renewal of cervical cancer stem cells through Hes1/NOTCH-1expression but little is known about factor(s) responsible for chemo- radioresistance of cancer stem cells. To understand this we have dissected the role of AP-1and its family members by using a herbal compound, curcumin and UV irradiation in cervical cancer. We isolated cervical cancer stem cells and enriched them by sequential gating from HPV+ve and HPV-ve human cervical cancer cell lines (SiHa and C33a) using a set of functional and phenotypic markers (ABCG2, CD49f, CD71, CD133). The isolated cervical cancer stem cells (SP+ve→CD49+veCD71−ve→CD133+ve) designated as CaCxSLCs displayed spheroid forming and self-renewal property with increased expression of HPVE6, AP-1 transcripts and a higher AP-1 DNA-binding activity compared to non-stem cancer cells (NSP−ve→CD49−veCD71+ve→ CD133−ve) or unsorted parental cells. Treatment with UV-radiation alone resulted in clonogenic survival of CaCxSLCs but not non-stem cancer cells with enhanced AP-1 expression and activation. In contrast, CaCxSLCs treated with UV in combination with curcumin, resulted in complete loss of AP-1 DNA-binding activity followed by decrease in sphere formation and percentage of SP cells but an increased expression of the fos-related antigen-1 (Fra-1) which has been earlier shown to us have tumor suppressor activity in cervical cancer.

Our study demonstrates a critical role of AP-1/Fra-1 signaling in imparting radiosensitization of cervical cancer stem cells. Curcumin, which down regulates almost all signalling pathways, including all members of AP-1 except Fra-1 indicating its role in chemo-radiosensitization of cancer stem cells. Thus combining curcumin with conventional cancer drugs may make cancer treatment most effective.

Citation Format: Bhudev C. Das, Abhishek Tyagi, Bal Gangadhar Roy, Alok C. Bharti. AP-1/Fra-1 as a target for therapy promotes chemoradiosensitivity of cancer and cancer stem cells. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2536.
Abstract 255: Docetaxel inhibits testosterone mediated activation of the AR pathway by SLCO1B3
Authors: de Morree Ellen S. , Aghai Ashraf , Gibson Alice A. , Mathijssen Ron H.J. , Wiemer Eric A.C. , Sparreboom Alex , van Weerden Wytske M. , de Wit Ronald
Published: July 2016

Background

Docetaxel is the first line of chemotherapy in metastatic castration resistant prostate cancer (mCRPC) patients. More than 50% of prostate cancer tumors express the solute carrier organic anion transporter family member 1B3 (SLCO1B3/OATP1B3), an uptake transporter that actively transports docetaxel into the cell. Interestingly, SLCO1B3 is also a transporter of endogenous substrates, such as testosterone. As the androgen receptor (AR) pathway is still active in mCRPC patients, we hypothesize that docetaxel can interact with the uptake of testosterone through SLCO1B3, which would result in decreased AR-pathway activation and subsequent tumor growth inhibition.

Materials and Methods

SLCO1B3 overexpressing cells (CHO-1B3) were used for uptake experiments with radioactively labeled hormones, such as estradiol-β-glucuronide (E2G). We stably transfected prostate cancers cells (PC346C-DCC and PC346C-DCC-G) with SLCO1B3 or with a green fluorescent protein (GFP) tag only. An androgen responsive element (ARE)-luciferase assay was created as a sensitive measure of AR pathway activation. ARE-activity and prostate specific antigen (PSA) production were analyzed with an ELISA assay after exposure to 1nM testosterone for 30 minutes with or without preincubation with docetaxel 10 μM in SLCO1B3 overexpressing and GFP- tagged control cells.

Results

SLCO1B3 overexpressing cells showed testosterone-mediated activation of the AR pathway: ARE-activity increased 6.4-fold and PSA production 7-fold in SLCO1B3-overexpressing cells as compared to control cells. Pre-incubation of CHO-1B3 cells with docetaxel resulted in reduced uptake of E2G to the level observed in control cells. Similarly, after exposure to testosterone and docetaxel ARE-activity was significantly decreased in SLCO1B3-overexpressing cells compared to that of controls.

Conclusion: Docetaxel inhibits the activation of the AR pathway via SLCO1B3. This is a novel anti-androgenic effect exerted by docetaxel in addition to inhibition of the AR translocation that we demonstrated previously. Experiments are ongoing to investigate if testosterone uptake via SLCO1B3 is inhibited by docetaxel.

Citation Format: Ellen S. de Morree, Ashraf Aghai, Alice A. Gibson, Ron H.J. Mathijssen, Eric A.C. Wiemer, Alex Sparreboom, Wytske M. van Weerden, Ronald de Wit. Docetaxel inhibits testosterone mediated activation of the AR pathway by SLCO1B3. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 255.
Abstract 2550: Identification of novel BRCA founder mutations in middle eastern breast cancer patients using capture and sanger sequencing analysis
Authors: Bu Rong , Siraj Abdul K. , Al-Obaisi Khadija A. S. , Beg Shaham , Al Hazmi Mohsen , Kong Yan , Ajarim Dahish , Al-Dayel Fouad , Al-Kuraya Khawla S.
Published: July 2016

Ethnic differences of breast cancer genomics have prompted us to investigate the spectra of BRCA1 and BRCA2 mutations in different populations. The prevalence and effect of BRCA 1 and BRCA 2 mutations in Saudi population is not fully explored. We conducted this study to characterize the prevalence of BRCA mutations in Middle Eastern breast cancer patients from Saudi Arabia. A total of 486 clinically high risk breast cancer patients were recruited from the King Faisal Specialist Hospital & Research Centre from 1990 and 2011. Comprehensive BRCA1 and BRCA2 mutation screening was performed using capture sequencing and/or Sanger Sequencing of all coding exons of BRCA1 and BRCA2 in 190 cases. Thereafter, the validation was done using a panel of detected mutations in an additional 296 high risk breast cancer cases. Among the total 486 cases analyzed, 9 deleterious BRCA mutations were identified in 28 (5.8%) cases, comprising 25 cases in BRCA 1 and three cases in BRCA 2. The six BRCA 1 recurrent mutations (c. 1140dupG, c.4065_4068delTCAA, c.4136_4137delCT, c.4524G>A, c.5251C>T and c.5530delC) accounted for 96% (24/25) of all BRCA 1 mutant cases in this cohort. The one recurrent BRCA 2

mutation (c.7007G>A) accounted for 66.6% (2/3) of all BRCA2 mutant cases. Haplotype analysis was performed to confirm two BRCA1 recurrent mutations are novel putative founder mutation. In this study our findings suggest that BRCA mutations account for substantial proportion of high risk breast cancer cases in Middle Eastern population. Knowing the spectrum and frequency of founder mutation in this population will help in developing cost-effective rapid screening assay which can facilitate genetic testing and counseling for breast cancer risk assessment.

Citation Format: Rong Bu, Abdul K. Siraj, Khadija A. S. Al-Obaisi, Shaham Beg, Mohsen Al Hazmi, Yan Kong, Dahish Ajarim, Fouad Al-Dayel, Khawla S. Al-Kuraya. Identification of novel BRCA founder mutations in middle eastern breast cancer patients using capture and sanger sequencing analysis. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2550.
Abstract 2555: Promoter DNA methylation patterns in breast tumor and matched adjacent non-tumor tissues in the breast cancer family registry
Authors: Wu Hui-Chen , Hibshoosh Hanina , Santella Regina , Terry Mary Beth
Published: July 2016

Alterations in DNA methylation occur frequently in breast carcinogenesis, but little is known about the DNA methylation changes in familial breast tumors. To examine whether the DNA methylation profiles in breast cancer tissues from high risk women from breast cancer families are similar to breast tumor tissues from The Cancer Genome Atlas project (TCGA), we measured DNA methylation by next generation sequencing in 48 genes identified in TCGA in 40 formalin-fixed, paraffin-embedded tumor tissues, and the corresponding adjacent non-tumor tissues from women with invasive breast cancer at the New York site of the Breast Cancer Family Registry (BCFR). We observed differences in DNA methylation patterns between tumor and normal adjacent tissue for five of the selected genes (RYR2, C1orf14, SLC7A14, SEPW1, and RPTOR). The methylation levels in tumor and adjacent tissues, respectively were 24% and 14% for RYR2, (p = 0.01), 55% and 29% for C1orf14 (p = 0.01), 32% and 21% for SLC7A14 (p = 0.002), 53% and 28% for RPTOR (p = 0.01) and 74% and 38% SEPW1 (p<0.0001). We only confirmed 5 of the 48 loci identified in TCGA in our sample of high risk women, suggesting genes identified from TCGA may be different than those in high-risk women. As tissue-specific methylation may prove to have strong prognostic significance, this suggests a critical need to engage in large-scale studies examining genome-wide DNA methylation profiles in high risk women in order to understand the etiology of familial breast cancer.

Citation Format: Hui-Chen Wu, Hanina Hibshoosh, Regina Santella, Mary Beth Terry. Promoter DNA methylation patterns in breast tumor and matched adjacent non-tumor tissues in the breast cancer family registry. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2555.
Abstract 2557: Germline mutations in renal cancer predisposing genes: Analysis of the Geisinger MyCode population
Authors: Williams Heinric , Metpally Raghu , Mohamed Mahmoud , Krishnamurthy Sarath , Kip Sertac , Carey David J. , Baras Aris , Overton John
Published: July 2016

Renal cell cancer (RCC) is not a single disease but is made up of a number of cancers, each with a unique histology, biology, clinical course and response to therapy. Alterations in at least 16 hereditary genes have been attributed to the risk of developing RCC. In this study, we describe the prevalence and spectrum of germline variants among these genes and highlight correlations between germline genotype with tumor phenotype. Using the Geisinger MyCode cohort, we sequenced the whole exomes of 42,933 subjects. Subjects were divided into those with a renal cancer diagnosis, other cancer diagnosis and no cancer diagnosis. We analyzed the DNA sequences of 16 hereditary renal cancer genes from each of these groups. The damaging mutations was determined by following ACMG guidelines. Among the 42,933 subjects in the Geisinger MyCode cohort, 168 were diagnosed with RCC. None of these subjects had a family history of RCC. Clear cell RCC (ccRCC) was the most predominant histology (77%), followed by Type 1 papillary RCC (7%), chromophobe RCC (6%), and Type 2 papillary RCC (5%). Mutations in all the predisposing genes were identified in all the renal cancer subtypes but only a subset were deemed damaging. The top 2 ccRCC predisposing genes with damaging or likely damaging mutations were TSC2 (8%) and SDHD (4%). While TSC2 damaging variants were also found in the other histologies, novel TSC2 variants were differentially associated with high grade and metastatic disease in ccRCC as compared to those with low grade or non-metastatic disease. The genes harboring damaging or likely damaging variants in Type 1 and Type 2 papillary RCC were MET and FH respectively. Predisposing RCC germline mutations were found in a significant number of subjects with sporadic RCC. Family history was unhelpful in predicting the affected subjects. Knowledge of these mutations would be beneficial in counseling patients and their families as well as improving our understanding of the disease to direct patient care.

Citation Format: Heinric Williams, Raghu Metpally, Mahmoud Mohamed, Sarath Krishnamurthy, Sertac Kip, David J. Carey, Aris Baras, John Overton. Germline mutations in renal cancer predisposing genes: Analysis of the Geisinger MyCode population. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2557.
Abstract 2558: A retrospective analysis of the spectrum of genetic variations associated with hereditary cancers in Indians
Authors: Mahadevan Lakshmi , Nair Aditya , Ramprasad Vedam L.
Published: July 2016

The hereditary cancer burden in India is on the rise due to an increase in awareness of the disease, decrease in the cost of genetic testing and opportunities for genetic counseling. More and more individuals from high risk families are undergoing genetic testing to assess their likelihood of developing the disease. On the other hand, the clinical community is facing a significant challenge on how to interpret and classify a variant as disease-causing or benign. This is because a large fraction of the variants identified in the affected individuals from India have not been reported in hereditary disease databases such as the Breast cancer Information Core (BIC), Clinvar and Swissvar. These variants of unknown significance (VUS) present in individuals from high risk families create a great deal of uncertainty on clinical follow up and disease management. We performed a retrospective analysis on more than 300 affected cases of hereditary ovarian and breast cancer tested at our genomics center in the last three years. We compiled all the known pathogenic variants and compared their distribution in the Indian cohort with what has been reported worldwide. The most prevalent mutation in BRCA1 p.Glu23Valfs*17 (185delAG) was detected at a frequency of 20.34% in line with what has been found worldwide. In addition, frameshift mutations in BRCA1 and BRCA2 were most frequently detected in breast and ovarian cancer in line with previous findings. Additionally, our analysis identified 13 novel previously unreported and potentially pathogenic variants in BRCA1 and BRCA2 genes. Variants were also detected in several moderate penetrance genes such as CHEK2, BARD1 and ATM involved in DNA damage response and in MSH2 and MSH6 genes regulating epigenetic control through chromatin modification. In this study, we report novel pathogenic variants in genes associated with hereditary breast and ovarian cancer in the Indian population.

Citation Format: Lakshmi Mahadevan, Aditya Nair, Vedam L. Ramprasad. A retrospective analysis of the spectrum of genetic variations associated with hereditary cancers in Indians. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2558.
Abstract 2581: Determinants for compliance to colorectal cancer screening in Korea: A multilevel analysis
Authors: Shin Aesun , Woo Hyeongtaek
Published: July 2016

BACKGROUND: This study aimed at investigating the individual and area level factors associated with colorectal cancer screening attendance.

METHODS: Colorectal cancer screening participation as well as other individual level data were gathered from the fifth Korea National Health and Nutrition Examination Survey, 2010-2012. The area level data were extracted from 2009 Health promotion strategies and programs development for health inequalities alleviation (Shin et al.,2009). Multilevel model was used for data analysis.

RESULTS: Information on a total of 8,783 individuals (3,777 men and 5,006 women) aged 50 years and older and deprivation index of each areas were used in the final analysis. Among individual level variables, men were more likely to participated in colorectal cancer screening within 5 years than women (58.0% for men vs 53.9% for women)(Odds Ratio (OR) = 0.85; 95% CI 0.73 to 0.99), and highest among age 60-69 (63.3%). Area level variables's explained class-level variance was 6.4%.

CONCLUSION: In this study, by applying the multilevel analysis we can find that colorectal cancer screening attendance rate is associated with both individual and community factors.

Citation Format: Aesun Shin, Hyeongtaek Woo. Determinants for compliance to colorectal cancer screening in Korea: A multilevel analysis. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2581.
Abstract 2601: Gingerol aspirinate derivatives as novel chemopreventive agents for colon cancer
Authors: Zhu Yingdong , Wang Fang , Zhao Yantao , Wang Pei , Sang Shengmin
Published: July 2016

Regular aspirin use has been convincingly shown to reduce the risk of colorectal cancer. However, long-term use of aspirin leads to gastrotoxicity. Herein, we designed and synthesized a novel class of gingerol- and shogaol-based aspirin prodrugs to simultaneously release aspirin and gingerol or shogaol to attenuate the side effects caused by aspirin. Prodrug GAS exerted enhanced anticancer activities, which are better than a physical mixture of aspirin and 6-gingerol as well as each individual. In addition, GAS eliminated the gastric toxicity induced by aspirin in mice. Metabolism of GAS in mice showed that the majority of GAS is decomposed to release 6-gingerol and aspirin or salicylic acid either in the intestine or after absorption. Mechanistic studies demonstrate GAS could dose-dependently inhibit COX pathway. These findings highlighted the improved anticancer properties of gingerol-based aspirin prodrugs. GAS may represent novel and safe alternatives of aspirin for the purpose of daily use in the future.

Citation Format: Yingdong Zhu, Fang Wang, Yantao Zhao, Pei Wang, Shengmin Sang. Gingerol aspirinate derivatives as novel chemopreventive agents for colon cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2601.
Abstract 2612: Zinc inhibits Orai1-mediated Ca2+ signals and proliferation in esophageal cancer cells
Authors: Choi Sangyong , Cui Chaochu , Luo Yanhong , Ko Jae-Kyun , Ma Jianjie , Fu Liwu , Korichneva Irina , Pan Zui
Published: July 2016

Intracellular Ca2+ signals, including oscillations, regulate proliferation, migration, and other cellular events in cancer cells. Zinc (Zn), an essential micronutrient, has been studied for its chemopreventive effects in several cancers, including esophageal cancer. Although there is a growing research interest in the cross-talk between Ca2+ and Zn signaling, it remains elusive as to how Zn prevents tumor growth and whether Ca2+ signaling is involved. Our previous report demonstrated that Orai1, a store-operated Ca2+ entry (SOCE) channel, is highly expressed in esophageal squamous cell carcinoma (ESCC) compared to normal tissues, and that the elevated expression of Orai1 is strongly associated with poor prognosis in patients. In the current study, we show that physiological levels of Zn can significantly suppress cell proliferation in KYSE-150, a human ESCC cell line. We also show that Zn is able to inhibit Orai1-mediated SOCE and intracellular Ca2+ oscillations, both which are known as proliferation signals. Based on the topology information of Orai1, we hypothesized that the histidine residue in linker region between transmembrane 1 and 2 of Orai1 (H113) as well as three cysteine residues may play a critical role in Zn-inhibitory effects. Using a point mutation approach, we exhibit that the Zn-inhibitory effects on both SOCE and cell proliferation are vanished in KYSE-150 cells containing Orai1 H113A mutant. Furthermore, KYSE-150 cells expressing Orai1 with any mutation in cysteine residues (C126A, C143A and C195A) display significant loss of Zn-inhibitory functions. These results indicate that the four amino acid residues are likely to be involved in Zn-inhibitory effects on SOCE and cell proliferation.

Taken together, our data suggest that dietary Zn may inhibit Orai1-mediated SOCE and intracellular Ca2+ signaling, which in turn suppresses cell proliferation in ESCC. Further studies are required to search for novel and effective prevention strategies as well as therapeutic options targeting on Zn and Ca2+ signaling in ESCC.

Citation Format: Sangyong Choi, Chaochu Cui, Yanhong Luo, Jae-Kyun Ko, Jianjie Ma, Liwu Fu, Irina Korichneva, Zui Pan. Zinc inhibits Orai1-mediated Ca2+ signals and proliferation in esophageal cancer cells. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2612.
Abstract 2619: Novel biomarkers and molecular alterations for breast cancer initiation and susceptibility
Authors: Marino Natascia , Johnson Mariah L. , Tanaka Hiromi , Wu Xi , Mathieson Theresa , Henry Jill E. , Ivan Mircea , Liu Yunlong , Rufenbarger Connie , Storniolo. Anna Maria V.
Published: July 2016

Background: Despite significant advances in diagnosis and treatment, breast cancer remains the leading cause of cancer-related death in women worldwide. Therefore, there is a critical need to identify molecular mechanisms responsible for cancer initiation and progression. To date, there have been attempts to identify biomarkers that can predict progression of pre-malignant lesions (i.e. DCIS) to invasive carcinoma. Our study aims to identify earliest markers of breast cancer initiation.

Methods: We evaluated local (breast tissue) and systemic (serum/plasma) molecular alterations associated with breast cancer susceptibility using the unique resources available at the Komen Normal Tissue Bank at IUSCC. Human specimens (serum/plasma and breast tissue) donated by women before their cancer was clinically detectable were used to identify circulating biomarkers that are associated with breast cancer risk. Specimens from age-matched controls were used for comparison. Sera/plasma were analyzed for circulating miRNAs and telomeric level in the cell-free circulating DNA (cfDNA). We employed next generation sequencing to obtain transcriptome in the “normal” breast of women who eventually developed breast cancer and age-matched control normal breast.

Results/Discussion: Serum/plasma of women who developed breast cancer showed variation in circulating miRNAs as well as telomeric cfDNA levels as compared to the healthy control group. Among 385 microRNAs detected in circulation, 10 miRNAs were present at different levels in the susceptible group. In addition, susceptible group displayed reduced levels of plasma telomeric cfDNA and telomere shortening in breast epithelium.

Transcriptome analysis of microdissected breast epithelium and stroma revealed molecular alterations in the “normal” breast tissue associated with cancer development. Pathway analyses of these differentially expressed genes are underway to determine the mechanisms associated with breast cancer initiation.

Conclusion/Impact: Functional analysis of biomarkers identified in this study may help in cancer risk assessment and improvement of preventive therapy.

Citation Format: Natascia Marino, Mariah L. Johnson, Hiromi Tanaka, Xi Wu, Theresa Mathieson, Jill E. Henry, Mircea Ivan, Yunlong Liu, Connie Rufenbarger, Anna Maria V. Storniolo. Novel biomarkers and molecular alterations for breast cancer initiation and susceptibility. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2619.
Abstract 262: Combination therapy of folate-targeted chemotherapeutics with anti-PD-1 antibody against folate receptor-positive tumors in immunocompetent murine models
Authors: Lu Yingjuan June , Wheeler Leroy W. , Cross Vicky , Westrick Elaine , Lloyd Alex , Leamon Christopher P.
Published: July 2016

The PD-1/PD-L1 (programmed cell death protein 1; programmed death-ligand 1) pathway plays a key role in immunological tolerance and autoimmunity. PD-1 is primarily expressed on activated T and B cells while its receptor, PD-L1, is expressed in a variety of cell types including resting lymphocytes, DCs, and macrophages. Recently, multiple human solid tumor types (melanoma, NSCLC, RCC, ovarian, and colorectal cancer) have been found to overexpress PD-L1 within its tumor microenvironment. More importantly, PD-1/PD-L1 blocking agents (pembrolizumab, nivolumab, lambrolizumab, MPDL3280A) have been found active as a single agent or in combination with chemotherapy and some have produced durable clinical responses. On the other hand, human epithelial tumors are also known to overexpress the high-affinity folate receptor (FR)-alpha that is capable of bringing folate-linked drugs into the cell cytosol via endocytosis. Using flow cytometry, we assessed PD-L1 expression in various FR-positive syngeneic mouse tumor models (M109, Renca, L1210A, 4T1-Cl2, ID8-Cl15). PD-L1 expression was found to vary significantly among different tumor types and could be found not only on CD45- malignant cells but also on tumor stromal cells such as F4/80+CD11b+ tumor-associated macrophages. Using a rat anti-mouse PD-1 antibody (clone RMP1-14), we studied in-vivo efficacy of a folate-targeted chemotherapy in combination with PD-1/PD-L1 blockage in PD-L1-expressing tumor models. In syngeneic models with high PD-L1 expression and tumor-infiltrating lymphocytes, a synergistic and curable anti-tumor effect was observed and the animals developed tumor-protective immunity against rechallenge. Thus, our preliminary results suggest that folate-targeted chemotherapeutics may also be enhanced by PD-1/PD-L1 blockage by means of overcoming tumor-mediated immune suppression

Citation Format: Yingjuan June Lu, Leroy W. Wheeler, Vicky Cross, Elaine Westrick, Alex Lloyd, Christopher P. Leamon. Combination therapy of folate-targeted chemotherapeutics with anti-PD-1 antibody against folate receptor-positive tumors in immunocompetent murine models. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 262.