bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract A05: Identification of RASA1 as a novel melanoma tumor suppressor gene
Authors: Sung Hyeran , Kanchi Krishna L. , Messina Jane , Lee Ji-Hyun , Ding Li , Wilson Richard K. , Weber Jeffrey S. , Kim Minjung 
Published: July 2015

Abstract
Hyperactivation of the Ras-Raf-Mitogen-activated protein kinase (MAPK) pathway via frequent activating mutations in NRAS and BRAF has been commonly observed in melanoma. Novel mutations in other components of this pathway such as MEK1, MEK2, MAP3K5, and MAP3K9 have been reported recently by high-throughput sequencing efforts. In addition, NF1 (neurofibromatosis type 1), one of the Ras GTPase activating proteins (RasGAPs), has been shown to be mutated or suppressed in melanoma. However, importance of other RasGAPs has not been addressed in melanoma.
To obtain a comprehensive view of melanoma genomes, we conducted whole genome sequencing (WGS) of 15 metastatic melanomas and matched normal PBMC genomes from 13 melanoma patients. All melanoma genomes from these 13 patients contained at least one mutation in genes of Ras-Raf-MAPK pathway (MAPK1, MAP3K1, MAP4K2, MAP3K14, NRAS, and BRAF). In addition, we identified two novel, clustered somatic missense mutations (p.Tyr472His and p.Leu481Phe) in RASA1 (RAS p21 protein activator 1, p120RasGAP) that negatively regulates Ras by catalyzing the hydrolysis of active Ras-GTP to inactive Ras-GDP. In this study, we addressed functional roles of RASA1 in melanoma tumorigenesis. Ectopic expression of wild-type RASA1 in human melanoma cell lines SKMEL28 and WM983C (with BRAF V600E) decreased, while RASA1 Y472H mutant enhanced soft agar colony formation, tumor growth, and Ras activity. The RASA1 L481F mutant lost its tumor suppressive activity. The siRNA- or shRNA-mediated knockdown of RASA1 promoted soft agar colony formation, tumor growth, and RAS activation in human melanoma cell lines IGR1 and KML1 (with BRAFV600E). Mechanistically, RASA1 required RasGAP activity to suppress colony formation and showed higher activity toward R-Ras isoform among Ras superfamily of small GTPases. To determine RASA1 level in melanocytic lesions, immunohistochemical analysis of RASA1 on human melanoma tissue microarray (TMA) was performed. RASA1 expression was frequently down-regulated in metastatic melanoma samples (11.4% (4/35) of lymph node metastasis and 3.4% (1/29) of distal metastases) compared to primary melanomas (33.3% (21/63)) and dysplastic nevi (44.1% (15/34)). Thus, these data support that RASA1 is a novel melanoma tumor suppressor that is inactivated by loss of expression or by mutation.
Citation Format: Hyeran Sung, Krishna L. Kanchi, Jane Messina, Ji-Hyun Lee, Li Ding, Richard K. Wilson, Jeffrey S. Weber, Minjung Kim. Identification of RASA1 as a novel melanoma tumor suppressor gene. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Melanoma: From Biology to Therapy; Sep 20-23, 2014; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(14 Suppl):Abstract nr A05.
Abstract A08: CADM1 is a TWIST1 regulated suppressor of melanoma invasion
Authors: Hartsough Edward J. , Weiss Michele B. , Rosenbaum Sheera R. , Aplin Andrew E. 
Published: July 2015

Abstract
Melanoma is the deadliest form of skin cancer; however, with early detection prior to metastatic dissemination, patients generally have a good prognosis. Recently, our lab has implicated the transcription factor TWIST1 in the progression of melanoma towards metastasis. In melanoma cells, we found that RAS-RAF-MEK-ERK (ERK1/2 pathway) signaling increases TWIST1 expression, which promotes invasive properties in the dermal microenvironment, at least in part by enhancing levels of the matrix metalloproteinase, MMP1. Other TWIST1-regulated targets are poorly described. In this study, we compared expression-profiling data from cells expressing shRNA against TWIST1 or cells overexpressing TWIST1 in order to identify TWIST1-regulated genes. KEGG and GO analysis revealed that TWIST1 is responsible for regulating a number of genes involved in cellular adhesion. We found that TWIST1 levels inversely correlate with levels of cell adhesion molecule 1 (CADM1, also known as NECL-2, IGSF4, TSLC1, SynCAM). Chromatin immunoprecipitation (ChIP) studies and promoter assays demonstrated that TWIST1 physically interacts with the CADM1 promoter and this is associated with reduced CADM1 levels. Additionally, CADM1 expression is inversely associated with ERK1/2 signaling and TWIST1 expression. Modulation of cellular CADM1 levels did not affect proliferation rates; however, overexpression of CADM1 augmented cell-cell interaction, cell aggregation, and reduced trans-endothelial invasion. Furthermore, exogenous CADM1 inhibited serum-directed migration and invasion through Matrigel-coated Boyden chambers, whereas knockdown of CADM1 was associated with enhanced migratory and invasive properties. Taken together, these data provide evidence that CADM1 is negatively regulated by TWIST1 and may act as a suppressor of melanoma invasion.
Citation Format: Edward J. Hartsough, Michele B. Weiss, Sheera R. Rosenbaum, Andrew E. Aplin. CADM1 is a TWIST1 regulated suppressor of melanoma invasion. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Melanoma: From Biology to Therapy; Sep 20-23, 2014; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(14 Suppl):Abstract nr A08.
Abstract A25: WWOX phosphorylation at Ser14 enhances melanoma docking and growth in the lung and liver in mice
Authors: Su Wan-Pei , Wang Wan-Jen , Chang Nan-Shan 
Published: July 2015

Abstract
Understanding of the fundamental cell behavior would help develop strategies for cancer stem cell eradication. Metastatic cancer cells tend to have epigenetically inactivated WWOX gene and are highly aggressive. Time-lapse microscopy revealed that they sense the surrounding WWOX-expressing normal or cancer cells, run away from them, and divide rapidly in order to survive. With time of growth and increased space pressure, these cancer cells grow as spheres with the expression of pluripotent stem cell markers such as Oct4, SSEA-4, TRA-1-60, and others. WWOX is re-expressed in the cancer stem cell spheres with S14 phosphorylation (pS14), suggesting that pS14WWOX is a potential cancer stem cell marker. Notably, organs, expressing pS14WWOX, are susceptible for melanoma cell docking and homing in vivo. Suppression of WWOX phosphorylation at Ser14 by micromolar levels of full-length Zfra1-31 or truncated Zfra4-10 prevents melanoma growth in the lung and liver in mice. Zfra stimulates non-T and non-B memory Hyal-2+ CD3- CD19- lymphocytes in the mouse spleens by binding to membrane hyaluronidase Hyal-2 and probably suppressing the TGF-beta/Hyal-2/WWOX/Smad4 signaling. In vitro education of Hyal-2+ CD3- CD19- cells suppresses melanoma growth in vivo.
Citation Format: Wan-Pei Su, Wan-Jen Wang, Nan-Shan Chang. WWOX phosphorylation at Ser14 enhances melanoma docking and growth in the lung and liver in mice. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Melanoma: From Biology to Therapy; Sep 20-23, 2014; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(14 Suppl):Abstract nr A25.
Abstract A33: Loss of tumor suppressors KAI1 and p27 identifies a unique subgroup of primary melanoma patients with poor survival
Authors: Cheng Yabin , Zhang Guohong , Tang Yun , Chen Guangdi , Safaee Gholamreza , Rotte Annand , Martinka Magdalena , McElwee Kevin , Zhou Youwen 
Published: July 2015

Abstract
Objective: Melanoma is a highly heterogeneous disease. A certain subgroup of patients with primary melanomas exhibits a greater potential to develop metastatic disease and thus has worse survival. The present study attempts to identify the molecular features shared by metastatic melanomas and the subgroup of primary melanomas, and use the information to assist clinicians to design personalized therapy for primary melanoma patients.
Patients and methods: Seven previously reported biomarkers, including BRAF, Dicer, Fbw7, KAI1, MMP2, p27 and Tip60, were investigated. A training cohort with 250 melanoma patients (145 primary melanomas and 105 metastatic melanomas) and an independent cohort with 92 primary melanoma patients were used for the study. Logistic regression analysis was used to identify discriminate biomarkers of metastatic melanoma from primary melanoma. Kaplan-Meier survival and multivariate Cox proportional hazard regression analysis were performed to assess the significance of the molecular signature in the prognosis of melanoma.
Results: In the training cohort, we found the loss expression of KAI1 and p27 to be most significant between metastatic and primary melanoma. The primary melanoma patients with loss expression of both KAI1 and p27 had poor 5-year survival in both training cohort (P = 0.002) and independent cohort (P = 0.03). Multivariate Cox regression analysis showed that the KAI1-/p27- signature was an independent factor for disease- specific survival (P = 0.004). More important, compared to KAI1 and p27 as an individual prognostic marker, the KAI1-/p27- signature is more closely associated with melanoma patient survival: the P value is 0.004 for KAI1-/p27-, and 0.044, 0.181 for KAI1 and p27, respectively.
Conclusion: Loss of both KAI1 and p27 defines a subgroup of primary melanoma patients with poor prognosis, and the combination signature is better than individual biomarker. The clinical significance of KAI1 and p27 warrants further assessment in prospective clinical trials.
Citation Format: Yabin Cheng, Guohong Zhang, Yun Tang, Guangdi Chen, Gholamreza Safaee, Annand Rotte, Magdalena Martinka, Kevin McElwee, Youwen Zhou. Loss of tumor suppressors KAI1 and p27 identifies a unique subgroup of primary melanoma patients with poor survival. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Melanoma: From Biology to Therapy; Sep 20-23, 2014; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(14 Suppl):Abstract nr A33.
Abstract B15: Combination chemotherapy in melanoma using EZH2 inhibitor
Authors: Sengupta Deepanwita , Avaritt Nathan L. , Tackett Alan J. 
Published: July 2015

Abstract
Melanoma is the deadliest variety of skin cancer, which according to the American Cancer Society (ACS) will account for around 9710 deaths and diagnosis of around 76,100 new melanoma cases in the current year. According to the ACS, melanoma is also the fastest growing cancer, and hence it is vital to investigate the pathogenesis involved in the advanced stage of melanoma, and design effective therapeutics for its treatment.
Aberrant activity of the histone methyltransferase enhancer of zeste homolog 2 (EZH2) has been reported to be associated with different types of cancer. The EZH2 catalyzes the deposition of the repressive mark histone H3 lysine 27 trimethylation (H3K27me3) on the promoter of the target genes using the catalytic SET domain, thereby epigenetically silencing the expression of the target genes. This is because the H3K27me3 mark results in chromatin compaction which reduces the accessibility of various transcription factors to the gene, and hence adversely affects transcription. Several of such EZH2 target genes have been found to be tumor suppressor genes like RUNX3, DAB2IP, and E-cadherin, and silencing of such tumor suppressor genes is a chief mechanism by which EZH2 leads to cancer progression. Hence derepression of the tumor suppressor genes by inhibition of EZH2 could be an effective treatment strategy in different types of cancer.
There has been no study till date investigating the role of EZH2 in melanoma. Our laboratory is investigating the role of EZH2 in the pathogenesis involved in the advanced stage of melanoma, to enable the design of effective therapeutic strategies for the treatment of melanoma. Drugs targeting epigenetic modifiers are becoming increasingly popular because of the fact that most epigenetic modifications and their effects can be reversed using these drugs. Our lab has strong evidence that metastatic (or advanced) melanoma is associated with upregulation of EZH2 and H3K27me3. We have also observed that EZH2 inhibition inhibits proliferation and invasion, and also induces apoptosis in metastatic melanoma cells. Recently our lab is performing combination chemotherapeutic studies in vitro, where EZH2 inhibitor GSK126 (S-adenosyl-methionine competitive inhibitor) is being used in combination with conventional chemotherapeutics like cisplatin and Bcl-2 inhibitors. Our results strongly suggest that when EZH2 inhibitor is used in combination with cisplatin or Bcl-2 inhibitor in metastatic melanoma cell lines, the inhibition is synergistic. This synergistic effect of GSK126 and cisplatin or Bcl-2 inhibitor has been found to be caspase-mediated.
Citation Format: Deepanwita Sengupta, Nathan L. Avaritt, Alan J. Tackett. Combination chemotherapy in melanoma using EZH2 inhibitor. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Melanoma: From Biology to Therapy; Sep 20-23, 2014; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(14 Suppl):Abstract nr B15.
Abstract B27: Wnt5A-expressing melanoma cells show classical markers of senescence following radiation and therapeutic stress, but retain the ability to metastasize and proliferate at distant sites
Authors: Webster Marie R. , Xu Mai , Kinzler Kathryn , Kaur Amanpreet , Appleton Jessica , O'Connell Michael P. , Marchbank Katie , Valiga Alexander , Dang Vanessa , Perego Michela , Zhang Gao , Slipicevic Ana , Keeney Frederick , Lehrmann Elin , Wood William , Becker Kevin , Kossenkov Andrew V. , Herlyn Meenhard , Murphy Maureen , Weeraratna Ashani T. 
Published: July 2015

Abstract
Senescence is a cytostatic cell fate that can be induced by oncogene activation, replicative stress or therapy-induced stress. Therapy-induced senescence (TIS) of tumor cells can be initiated by anti-cancer compounds or radiation. TIS is generally considered to be irreversible, and as such this process is believed to be a desirable therapeutic outcome. In this study, we show that melanomas characterized by high levels of the signaling molecule Wnt5A respond to irradiation by undergoing growth arrest, and by expressing classical markers of senescence, including positivity for senescence-associated beta-galactosidase (SA-β-gal), senescence associated heterochromatic foci (SAHF), H3K9Me chromatin marks, and PML bodies. Even though these cells are positive for classical markers of senescence, we find that they retain their ability to migrate and invade. Further, these Wnt5A-high cells are able to proliferate following metastasis and form new tumors in the lung, while expressing increased markers of senescence. Silencing Wnt5A reduces expression of these senescence markers and decreases invasiveness. Finally, Wnt5A-high melanoma cells treated with PLX4720, a BRAFV600E targeted therapy, also increase markers of a TIS response, while remaining invasive. The combined data challenge the paradigm that TIS is a desirable therapeutic endpoint. They also point to Wnt5A as a master regulator of this senescence-like stress-induced phenotype in melanoma.
Citation Format: Marie R. Webster, Mai Xu, Kathryn Kinzler, Amanpreet Kaur, Jessica Appleton, Michael P. O'Connell, Katie Marchbank, Alexander Valiga, Vanessa Dang, Michela Perego, Gao Zhang, Ana Slipicevic, Frederick Keeney, Elin Lehrmann, William Wood, III, Kevin Becker, Andrew V. Kossenkov, Meenhard Herlyn, Maureen Murphy, Ashani T. Weeraratna. Wnt5A-expressing melanoma cells show classical markers of senescence following radiation and therapeutic stress, but retain the ability to metastasize and proliferate at distant sites. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Melanoma: From Biology to Therapy; Sep 20-23, 2014; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(14 Suppl):Abstract nr B27.
Abstract B32: Responses of direct in vivo melanoma xenograft cells to targeted therapeutics
Authors: Basken Joel , Fujita Mayumi , Ahn Natalie 
Published: July 2015

Abstract
The purpose of this study was to investigate the mechanism of resistance of a melanoma cell line generated from a direct in vivo xenograft (DIVX) model. Although BRAF and MKK1/2 inhibitors have produced positive clinical responses in melanoma patients with BRAF-V600 mutations, between 25-50% of patients show intrinsic resistance. Deciphering the mechanisms of intrinsic resistance will be critical for developing future treatment strategies. MB947P cells were established from a direct in vivo xenograft of a resected metastatic melanoma and exhibited innate resistance to apoptosis induced by MKK1/2 inhibitor (AZD6244/selumetinib). In contrast, the established metastatic melanoma cell line, WM239A, showed a strong apoptotic response, induced by inhibitor. Microarray expression profiling was carried out on MB947P and WM239A cells in the presence and absence of drug. The results showed that in MB947P cells inhibitor-dependent induction of Bim was minimal. In contrast, Bim was strongly induced by inhibitor in WM239A cells, where siRNA knockdown of Bim demonstrated its requirement for the apoptotic response. This suggests that the lack of apoptotic response in MB947P cells may be caused by a block in Bim induction through an unknown mechanism. Finally, co-culture of MB947P and WM239A cells showed partial inhibition of the apoptotic response in WM239A cells after AZD6244 treatment. This suggests the potential existence of a soluble factor in MB947P cells that confers resistance to apoptosis in WM239A cells. We propose that mechanisms for resistance to apoptosis in direct in vivo xenograft cell lines may ultimately inform mechanisms for resistance in patient tumors.
Citation Format: Joel Basken, Mayumi Fujita, Natalie Ahn. Responses of direct in vivo melanoma xenograft cells to targeted therapeutics. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Melanoma: From Biology to Therapy; Sep 20-23, 2014; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(14 Suppl):Abstract nr B32.
Abstract B33: PKC resistance in uveal melanoma is mediated by activation of AKT and reversed by BYL719, the PI3Kα inhibitor
Authors: Musi Elgilda , Ambrosini Grazia , Schwartz Gary K. 
Published: July 2015

Abstract
Uveal melanoma is the one of most common intraocular malignancies of the adult eye. Recently, Protein Kinase C (PKC) inhibitors have been used, as single agent and in combination, to treat GNAQ/GNA11-mutant uveal melanoma. However, patients may develop resistance to drug therapy. We have studied mechanisms of PKC resistance in uveal melanoma by exposing GNAQ/GNA11 mutant cell lines (92.1, Omm1.3 and Omm1) to increasing concentrations of the PKC inhibitor AEB071 for extended periods of time. Cell survival, as measured by cell proliferation assays, indicates IC50s of &gt; 5μM, ten times higher than the sensitive parental cells. Western blot analysis indicates increased expression of p-MARCKS (the PKC substrate), p-ERK and p-AKT in the resistant cells. When treated with AEB071, there was no evidence of PKC enzyme inhibition and no suppression of p-MARCKS, p-ERK or p-AKT. Though resistant to AEB071, treatment of the resistant cells with BYL719, a PI3Kα inhibitor, shows inhibition of cell growth (IC50s between 1 and 2 μM) with inhibition of p-AKT similar to that of the parental cells. Furthermore, this effect on growth inhibition can be enhanced by combining AEB071 with BYL719 resulting in inhibition of p-ERK, p-S6 and p-AKT despite persistent activation of p-MARCKS. Analysis of p-glycoprotein (MDR) in the PKC resistant cell lines showed no differences when compared to the parental cell lines, suggesting that this effect is not due to differences in drug accumulation. These studies support the combination of AEB071 and BYL719 as a means to maintain sensitization to PKC inhibitor therapy despite the onset of drug resistance. A clinical trial with AEB071 and BYL719 will be initiated shortly.
Citation Format: Elgilda Musi, Grazia Ambrosini, Gary K. Schwartz. PKC resistance in uveal melanoma is mediated by activation of AKT and reversed by BYL719, the PI3Kα inhibitor. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Melanoma: From Biology to Therapy; Sep 20-23, 2014; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(14 Suppl):Abstract nr B33.
Abstract B38: Melanoma patient-derived xenografts accurately models the disease and develop fast enough to guide treatment decisions
Authors: Einarsdottir Berglind O. , Bagge Roger Olofsson , Bhadury Joydeep , Jespersen Henrik , Nilsson Lisa M. , Mattsson Jan , Truvé Katarina , Naredi Peter , Nilsson Ola , Lopez Marcela Davila , Stierner Ulrika , Ny Lars , Nilsson Jonas A. 
Published: July 2015

Abstract
The development of novel therapies against melanoma would benefit from individualized tumor models to ensure the rapid and accurate identification of biomarkers of therapy response. Previous studies have suggested that patient-derived xenografts (PDXes) could be used in biomarker of response discovery. However, the clinical utility of PDXes in guiding real-time treatment decisions have only been reported in anecdotal forms. In the present study we aimed to develop a platform of melanoma patient-derived xenografts (PDXes), to assess whether treatment responses in mice would be applicable as a pre-selection tool for clinical trials. To that end, tumor biopsies from patients with stage III and IV metastatic malignant melanoma were transplanted into immunocompromised mice. Most melanoma biopsies generated serially transplantable PDX models, and their histology, and mutation status resembled their corresponding patient biopsy. RNAseq demonstrated that the expression profiles of the tumors are maintained throughout several passages in mice. The potential treatment for one patient was revealed by an in vitro drug screen and treating PDXes with the MEK inhibitor trametinib. In another patient, the BRAF mutation predicted the response of both the patient and its corresponding PDXes to MAP kinase pathway-targeted therapy. Importantly, in this unselected group of patients, the time from biopsy for generation of PDXes until death was significantly longer than the time required to reach the treatment phase of the PDXes. Thus, we demonstrate that it would be clinically meaningful to use this type of platform for a large proportion of melanoma patients as a pre-selection tool in clinical trials.
Citation Format: Berglind O. Einarsdottir, Roger Olofsson Bagge, Joydeep Bhadury, Henrik Jespersen, Lisa M. Nilsson, Jan Mattsson, Katarina Truvé, Peter Naredi, Ola Nilsson, Marcela Davila Lopez, Ulrika Stierner, Lars Ny, Jonas A. Nilsson. Melanoma patient-derived xenografts accurately models the disease and develop fast enough to guide treatment decisions. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Melanoma: From Biology to Therapy; Sep 20-23, 2014; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(14 Suppl):Abstract nr B38.