bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract A07: Activating mutations in uveal melanoma convey sensitivity to g-alpha q inhibition
Authors: Hitchman Tyler D. , Ceraudo Emilie , Moore Amanda R. , Shoushtari Alexander N. , Francis Jasmine H. , Guan Youxin , Chen Juliet , Chang Matthew T. , Taylor Barry S. , Sakmar Thomas P. , Huber Thomas , Chi Ping , Chen Yu 
Published: June 2022

Abstract
Uveal melanoma (UVM) is the most common intraocular malignancy, which represents about 5% of all melanoma cases per year in the United States. Half of all patients eventually develop metastatic disease, resulting in an average survival rate of six months and a five-year survival rate of ~15%. Recent studies have revealed the underlying genetic landscape of uveal melanoma but have not resulted in any therapeutic options to effectively treat UVM. UVMs harbor mutually exclusive activating mutations in GPCR signaling: ~90% in G-protein alpha q (Gq) subunits GNAQ/GNA11, ~5% in the GPCR CYSLTR2, and ~4% in a downstream effector. These mutations aberrantly activate canonical PLCβ signaling: cleavage of PIP2 into DAG and IP3, both of which lead to PKC activation. In addition to uveal melanoma, recent studies have shown this exact pathway to be activated in a subset of cutaneous and mucosal melanomas as well as other diseases like blue nevi, leptomeningeal melanocytic neoplasms (LMNs), and Sturge-Weber syndrome. My project focuses on understanding how Gq signals in UVM tumorigenesis and if Gq inhibition has therapeutic potential in UVM by addressing the following aims: 1) Using a highly specific Gq inhibitor, I will ask how Gq inhibition effects different activating mutations in UVM using representative in vitro models. I have generated melanocytes dependent on different mutations in the PLCβ pathway to study pathway inhibition and therapeutic efficacy. Based on my preliminary data I will also interrogate the mechanistic basis for Gq inhibition sensitivity in GNAQQ209L driven melanocytes. 2) Determining clinical potential of this drug by testing its pharmacologic properties in vivo. Using the melanocytes I have generated along with UVM cell lines and our GEMM, we will be able to thoroughly test the drug’s efficacy against a variety of xenografts. 3) Taking advantage of the ability to inhibit active Gq, I will aim to identify other pathways activated downstream of Gq using proteomic and transcriptomic approaches. This may provide alternative therapeutic strategies to target this recalcitrant disease. The outcome of this research will indicate the effectiveness of Gq inhibition in UVM as well as elucidate currently unknown signaling pathways essential for UVM tumorigenesis.
Citation Format: Tyler D. Hitchman, Emilie Ceraudo, Amanda R. Moore, Alexander N. Shoushtari, Jasmine H. Francis, Youxin Guan, Juliet Chen, Matthew T. Chang, Barry S. Taylor, Thomas P. Sakmar, Thomas Huber, Ping Chi, Yu Chen. Activating mutations in uveal melanoma convey sensitivity to g-alpha q inhibition [abstract]. In: Proceedings of the AACR Special Conference on Melanoma: From Biology to Target; 2019 Jan 15-18; Houston, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(19 Suppl):Abstract nr A07.
Abstract A15: New treatment opportunities by in vivo and in vitro screening approaches in melanoma
Authors: Marocchi Federica , Granieri Letizia , Lotti Fiorenza , Palluzzi Fernando , Costanza Jole , Riva Laura , Bossi Daniela , Lanfrancone Luisa 
Published: June 2022

Abstract
Treatment of metastatic melanoma has been recently revolutionized by the use of targeted and immune inhibitors, though efficiently working only in a fraction of patients. Adverse effects still represent major challenges, as well as the rapid development of drug resistance upon treatment, thus suggesting that it is of utmost importance to elucidate additional molecular pathways and targets to better understand the biology of this tumor. In vivo RNAi screens done in patient-derived xenografts (PDXs) that fully phenocopy the original tumor of the patient represent a powerful tool to identify new putative essential and druggable candidates, and to repurpose drugs already approved for other indications. To this end we have recently generated a platform of melanoma PDXs with which we can recapitulate both melanoma growth and metastasization. We have performed in vivo shRNA screens, where we have found numerous and patient-specific epigenetic genes essential for tumor growth in vivo. With this platform, we have isolated novel frailties whose depletion favors cell senescence. Preliminary data using shRNA libraries of actionable genes for which drugs are already available suggest that specific drugs can be repurposed for melanoma treatment. We have proved that this approach can work in vivo, and we propose to convert it in an in vitro assay to rapidly translate new discoveries to the patient.
Note: This abstract was not presented at the conference.
Citation Format: Federica Marocchi, Letizia Granieri, Fiorenza Lotti, Fernando Palluzzi, Jole Costanza, Laura Riva, Daniela Bossi, Luisa Lanfrancone. New treatment opportunities by in vivo and in vitro screening approaches in melanoma [abstract]. In: Proceedings of the AACR Special Conference on Melanoma: From Biology to Target; 2019 Jan 15-18; Houston, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(19 Suppl):Abstract nr A15.
Abstract A20: 17-Aminogeldanamycin inhibits cytoprotective UPR pathways and cooperates with inhibitors of the MAPK signaling cascade in apoptosis induction
Authors: Mielczarek-Lewandowska Aleksandra H. , Hartman Mariusz L. , Sztiller-Sikorska Malgorzata M. , Osrodek Marta , Gajos-Michniewicz Anna E. , Czyz Malgorzata E. 
Published: June 2022

Abstract
Geldanamycin is an inhibitor of Heat Shock Protein 90 (HSP90). Attenuation of HSP90 activity results in accumulation of unfolded proteins, induction of endoplasmic reticulum (ER) stress, and activation of unfolded protein response (UPR). HSP90 is a chaperone protein participating in appropriate folding of more than 100 proteins, including IRE1α and BRAFV600E. In melanoma cells, BRAFV600E was correlated with chronically induced ER stress and involved in UPR-induced resistance to apoptosis. As geldanamycin is highly hepatotoxic, geldanamycin derivatives exerting similar proapoptotic properties but higher selectivity towards cancer cells are needed. In the present study, 17-aminogeldanamycin exerted higher proapoptotic activity than geldanamycin in patient-derived melanoma cell populations as demonstrated by using fluorescence time-lapse imaging (IncuCyte ZOOM). We have also shown that 17-aminogeldanamycin inhibits ERK1/2 activity and cell proliferation,as well as induces apoptosis transiently, enhancing expression of HSP70 and GRP78. GRP78 regulates activity of the UPR pathway, and we have demonstrated that 17-aminogeldanamycin inhibits IRE1α-dependent pathway of UPR responsible for degradation of unfolded proteins and reduces levels of 36 kDa product of ATF6 cleavage in selected melanoma cell populations. Moreover, we have shown that combination of 17-aminogeldanamycin and trametinib induces apoptosis earlier and more efficiently. Our study suggests that cooperation of 17-aminogeldanamycin and trametinib might result from concurrent inhibition of the MAPK and protective UPR pathways but can be also associated with the basal UPR activity, which is diverse among drug-naïve melanoma cell populations. Further studies are necessary to fully explore antimelanoma capabilities of 17-aminogeldanamycin and its combination with targeted therapy. This work was financially supported by Grant 2014/15/B/NZ7/00947 from National Science Centre (Poland), and 502-03/1-156-01/502-14-318 from Medical University of Lodz.
Citation Format: Aleksandra H. Mielczarek-Lewandowska, Mariusz L. Hartman, Malgorzata M. Sztiller-Sikorska, Marta Osrodek, Anna E. Gajos-Michniewicz, Malgorzata E. Czyz. 17-Aminogeldanamycin inhibits cytoprotective UPR pathways and cooperates with inhibitors of the MAPK signaling cascade in apoptosis induction [abstract]. In: Proceedings of the AACR Special Conference on Melanoma: From Biology to Target; 2019 Jan 15-18; Houston, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(19 Suppl):Abstract nr A20.
Abstract A22: Effects of CDK4/6/MAPK targeting combinations on melanoma and the tumor immune microenvironment
Authors: Teh Jessica L.F. , Cheng Phil F. , Erkes Dan E. , Purwin Timothy J. , Field Conroy , Hollingworth Connor , Aguirre-Ghiso Julio , Levesque Mitch P. , Dummer Reinhard , Aplin Andrew E. 
Published: June 2022

Abstract
Trials utilizing cyclin-dependent kinases 4/6 (CDK4/6) inhibitor alone or in combination with BRAF and MEK inhibitors are under way in melanoma, but their use needs to be optimized. MEK plus CDK4/6i combinations lead to tumor regressions in vivo; however, residual disease and acquired resistance frequently persisted. Previously, we showed that amplification or mutation of NRAS was associated with acquired resistance in in vivo mutant NRAS models and mutant BRAF patient samples, respectively. These mechanisms led to upregulation of mTOR-S6 pathway. Here, we observed upregulation of dormancy signature and increased NR2F1 expression in residual disease. To further identify targetable pathway alterations associated with these resistance mechanisms, we have established longitudinal cell lines from multiple metastases from a single patient on the LOGIC2 (BRAF-MEK-CDK4/6i) trial. RPPA analysis highlights differences between the lines that we are further analyzing in functional assays. There is also increasing evidence that CDK4/6 inhibitors (CDK4/6i) may regulate the tumor immune microenvironment. We show that MEK plus CD4/6i led to better control of tumor growth in syngeneic models compared to immune-deficient NSG mice. The response to MEK plus CDK4/6i was associated with increased infiltration of CD8 positive T cells and T-cell activation markers. Together, we aim to identify mechanisms underlying resistance/tolerance to MEK plus CDK4/6i and to determine effects on the tumor immune microenvironment to inform potential new treatment strategies.
Citation Format: Jessica L.F. Teh, Phil F. Cheng, Dan E. Erkes, Timothy J. Purwin, Conroy Field, Connor Hollingworth, Julio Aguirre-Ghiso, Mitch P. Levesque, Reinhard Dummer, Andrew E. Aplin. Effects of CDK4/6/MAPK targeting combinations on melanoma and the tumor immune microenvironment [abstract]. In: Proceedings of the AACR Special Conference on Melanoma: From Biology to Target; 2019 Jan 15-18; Houston, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(19 Suppl):Abstract nr A22.
Abstract A26: Humanized mouse model: A model to understand mechanisms of immune non-responsiveness to immune checkpoint inhibitors in melanoma
Authors: Somasundaram Rajasekharan , Samarkina Anastasia , Connelly Thomas , Choi Robin , Choi Hedy , Muthumani Kar , Xu Xiaowei , Kaestner Klaus , Herlyn Meenhard 
Published: June 2022

Abstract
Immune checkpoint inhibitor therapy (anti-CTLA4 or anti-PD1 antibodies) is rapidly emerging as a front-line treatment option for many solid tumors. However, only a third of melanoma patients respond to immune checkpoint blockade. Currently available mouse xenograft and transgenic models have many shortcomings and are unable to address the basis of therapy resistance and immune nonresponsiveness that are observed in patients. Thus, there is an urgent need to establish an in vivo model with a human immune microenvironment that can address issues of therapy resistance. Our laboratory has developed a novel humanized mouse melanoma model. Immunodeficient NSG mice were reconstituted with human CD34+ cells and after 8-12 weeks, mice are fully reconstituted with human innate (monocyte/myeloid lineage cells, dendritic cells and NK cells) and adaptive (T and B cells) immune cells. Humanized mice were then challenged with HLA-matched melanoma cells, and the functional ability of human immune cells to restrict tumor growth was monitored. Delayed tumor growth was observed in humanized mice, indicating in vivo sensitization of human immune cells to melanoma. This was confirmed by in vitro demonstration of human lymphocytes from tumor-bearing mice showing enhanced cytokine expression after stimulation with melanoma antigen peptides. In therapy studies, tumor-bearing humanized mice treated with anti-PD-1 showed restricted tumor growth. Anti-PD-1 therapy resulted in enhanced infiltration of T cells that correlated with tumor response. MassCyTOF studies were performed using a panel of immune markers to understand the mechanism of therapy nonresponsiveness in some tumors. Downmodulation of HLA-class I molecules and increased presence of FOXP3+ cells in the tumor region were seen. Our results suggest that humanized mouse melanoma model can be explored further to understand the causes of therapy resistance and immune nonresponsiveness.
Citation Format: Rajasekharan Somasundaram, Anastasia Samarkina, Thomas Connelly, Robin Choi, Hedy Choi, Kar Muthumani, Xiaowei Xu, Klaus Kaestner, Meenhard Herlyn. Humanized mouse model: A model to understand mechanisms of immune non-responsiveness to immune checkpoint inhibitors in melanoma [abstract]. In: Proceedings of the AACR Special Conference on Melanoma: From Biology to Target; 2019 Jan 15-18; Houston, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(19 Suppl):Abstract nr A26.
Abstract A28: Identification of NGLY1-mediated protein deglycosylation as a vulnerable point in melanoma
Authors: Lin Victor , Zolekar Ashwini , Mishra Nigam , Ho Yin Ying , Hayatshahi Hamed , Parab Abhishek , Sampat Rohit , Liao Xiaoyan , Hoffmann Peter , Liu Jin , Emmitte Kyle , Wang Yu-Chieh 
Published: June 2022

Abstract
Although NGLY1 is known as a pivotal enzyme that catalyzes the deglycosylation of denatured glycoproteins, information regarding the responses of human cancer and normal cells to NGLY1 suppression is limited. While studying the NGLY1 deficiency-caused neurodevelopmental variations in patients with a congenital deglycosylation disorder, we made an intriguing discovery that the expression of NGLY1 appears to be dysregulated in human melanoma cells. We have examined how NGLY1 expression affects viability, tumor growth, and responses to therapeutic agents in melanoma cells and an animal model. Molecular mechanisms contributing to NGLY1 suppression-induced anticancer responses were revealed by systems biology and chemical biology studies. Using computational and medicinal chemistry-assisted approaches, we established novel NGLY1-inhibitory small molecules. Compared with normal cells, NGLY1 was upregulated in melanoma cell lines and patient tumors. NGLY1 knockdown caused melanoma cell death and tumor growth retardation. Targeting NGLY1 in melanoma cells induced pleiotropic responses, predominantly stress signaling-associated apoptosis and cytokine surges, which synergize with the antimelanoma activity of standard chemotherapy and targeted therapy agents. Pharmacologic and molecular biology tools that inactivate NGLY1 elicited highly similar responses in melanoma cells. Unlike normal cells, melanoma cells presented distinct responses and high vulnerability to NGLY1 suppression. Our work demonstrated the significance of NGLY1 in melanoma cells, provided mechanistic insights into how NGLY1 inactivation leads to eradication of melanoma with limited impact on normal cells, and suggested that targeting NGLY1 represents a novel antimelanoma strategy with the opportunity of a broad therapeutic window.
Citation Format: Victor Lin, Ashwini Zolekar, Nigam Mishra, Yin Ying Ho, Hamed Hayatshahi, Abhishek Parab, Rohit Sampat, Xiaoyan Liao, Peter Hoffmann, Jin Liu, Kyle Emmitte, Yu-Chieh Wang. Identification of NGLY1-mediated protein deglycosylation as a vulnerable point in melanoma [abstract]. In: Proceedings of the AACR Special Conference on Melanoma: From Biology to Target; 2019 Jan 15-18; Houston, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(19 Suppl):Abstract nr A28.
Abstract B08: Identification and characterization of Rho family GTPases as drivers of drug resistance in BRAFV600 mutant melanoma
Authors: Schillo Jacob L. , Feddersen Charlotte R. , Varzavand Afshin , Vaughn Hayley R. , Wadsworth Lexy S. , Voigt Andrew P. , Zhu Eliot Y. , Riordan Jesse D. , Stipp Christopher S. , Dupuy Adam J. 
Published: June 2022

Abstract
The serine/threonine protein kinase BRAF is mutated in approximately 50% of cutaneous melanomas, leading to hyperactivation of the MAPK/ERK pathway. The most common mutations, BRAFV600, can be targeted by selective kinase inhibitors, such as vemurafenib. Although initial clinical response to BRAF inhibition (BRAFi) is encouraging, 90% of patients develop drug resistance within a few months. Drug resistance can be delayed, but not prevented, by combining BRAFi with an MEK inhibitor (MEKi), such as cobimetinib. While some resistance mechanisms are known, disease progression on drug cannot be explained in all patients. We performed a gain-of-function mutagenesis screen utilizing the Sleeping Beauty transposon system to identify novel drivers of resistance in BRAFV600E mutant melanoma cells sensitive to current therapies. We chose four of the top candidates from our screen and validated the ability to drive resistance to both vemurafenib and vemurafenib-cobimetinib combination treatment in multiple melanoma cell lines. In an effort to determine the broader role of candidate vemurafenib-resistance drivers, we conducted an additional in vivo mutagenesis screen, of which genetic analysis is ongoing. Our initial cell-based screen identified two members of the Dbl family of guanine nucleotide exchange factors (GEFs), VAV1 and MCF2, as candidate drivers of vemurafenib resistance. A375 melanoma cells overexpressing VAV1 or MCF2 maintain significant growth under vemurafenib treatment, while control cells do not. Functional tests of VAV1 and MCF2 identified that the active form of two Rho family members, RAC1 and CDC42, increases following treatment with vemurafenib, suggesting a PAK-mediated pathway of resistance. In addition, all candidates that were tested elevated ERK signaling in the presence of vemurafenib. Many of the extracellular signaling pathways known to drive increased vemurafenib resistance activate Rho signaling. Our results suggest that Dbl family members may play an important role in this process. Understanding how Rho activation occurs and its consequences for drug resistance in melanoma will provide critical insights into the design and validation of future targeted therapies.
Citation Format: Jacob L. Schillo, Charlotte R. Feddersen, Afshin Varzavand, Hayley R. Vaughn, Lexy S. Wadsworth, Andrew P. Voigt, Eliot Y. Zhu, Jesse D. Riordan, Christopher S. Stipp, Adam J. Dupuy. Identification and characterization of Rho family GTPases as drivers of drug resistance in BRAFV600 mutant melanoma [abstract]. In: Proceedings of the AACR Special Conference on Melanoma: From Biology to Target; 2019 Jan 15-18; Houston, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(19 Suppl):Abstract nr B08.
Abstract B12: Potential neoantigen release and increased lymphocyte activity is facilitated by matrix metalloproteinase-dependent cleavage of mutant matrisome peptides in cutaneous melanoma
Authors: Zaman Saif , Chobrutskiy Boris I. , Patel Jay S. , Callahan Blake M. , Mihyu Moody , Diviney Andrea , Tong Wei Lue , Blanck George 
Published: June 2022

Abstract
Introduction: Proteases in the cancer microenvironment have been studied for decades, with a general conclusion that such proteases facilitate the spread of cancer, although there is some controversy regrading that conclusion in later stages of cancer development. More recently, a very large collection of data regarding mutant amino acids in the potential substrates of the cancer microenvironment has become available.
Methods: To better understand the potential impact of these mutant amino acids on protease function and cancer progression, we established a bioinformatics approach to assessing the impact of melanoma mutants, among a previously defined set of ECM structural proteins, on MMP2, a protease extensively associated with melanoma in terms of both protease sensitivity and MHC class I binding using original software. Additionally, T-cell receptor TRα and TRβ recombinations were bioinformatically obtained using whole-exome sequencing data from 479 melanoma tumor samples.
Results: Tumor samples with mutant amino acids adjacent to ECM structural protein, MMP2-cleavage sites represented a better survival rate and a larger proportion of mutant peptides with high HLA class I binding affinities, particularly in comparison to melanoma samples lacking a T-cell infiltrate. Furthermore, even better MHC class I binders, as a group, were identified among the sample representing ECM structural proteins mutants not adjacent to MMP2 sensitive sites and evincing a relatively poor survival rate.
Conclusion: Overall, this analysis suggested that MMP2 has the capacity of freeing mutant peptides that could facilitate an antitumor response and a better survival rate, and this analysis has the potential of resolving some of the controversy surrounding the role of cancer proteases in cancer progression.
Citation Format: Saif Zaman, Boris I. Chobrutskiy, Jay S. Patel, Blake M. Callahan, Moody Mihyu, Andrea Diviney, Wei Lue Tong, George Blanck. Potential neoantigen release and increased lymphocyte activity is facilitated by matrix metalloproteinase-dependent cleavage of mutant matrisome peptides in cutaneous melanoma [abstract]. In: Proceedings of the AACR Special Conference on Melanoma: From Biology to Target; 2019 Jan 15-18; Houston, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(19 Suppl):Abstract nr B12.
Abstract B13: Intrinsic microsomal PGE2 synthase-1 associates with poor patient survival and T-cell infiltration, and regulates immunosuppression in human and mouse melanoma models
Authors: Kim Sun-Hee , Roszik Jason , Cho Sungnam , Ogata Dai , Ekmekcioglu Suhendan , Grimm Elizabeth A 
Published: June 2022

Abstract
Our research has identified microsomal prostaglandin E2 synthase 1 (mPGES1) as an important downstream effector of the cyclooxygenase 2 (COX2) pathway often expressed by melanoma cells, and largely responsible for tumor-mediated immunosuppression. We observed clear correlations in expression and co-localization of COX2 and mPGES1, for which both are associated with increased expression of immunosuppressive markers in human melanoma. In a syngeneic melanoma mouse model, mPGES1 knockout increased melanoma expression of PD-L1 showing about 25% positive cells, increased infiltration of CD8a+ T cells (around 8 fold) and CD8a+ dendritic cells (around 10 fold) into tumors and suppressed tumor growth (around 70%). Durable tumor regression was observed in mice bearing mPGES1 knockout tumors that were given anti-PD-1 therapy. Analysis of a stage III melanoma tissue microarray revealed significant associations between high mPGES1 expression and low CD8+ infiltration, which correlated with poor survival. Collectively, our results are the first to illustrate a potential role for mPGES1-inhibition and selective targeting in melanoma immune evasion and in supporting the durability of response to PD-1 checkpoint immunotherapy. Research in the development of mPGES1 inhibitors is needed to validate their use as safe treatment options, but they appear attractive and feasible based on data to date.
Citation Format: Sun-Hee Kim, Jason Roszik, Sungnam Cho, Dai Ogata, Suhendan Ekmekcioglu, Elizabeth A Grimm. Intrinsic microsomal PGE2 synthase-1 associates with poor patient survival and T-cell infiltration, and regulates immunosuppression in human and mouse melanoma models [abstract]. In: Proceedings of the AACR Special Conference on Melanoma: From Biology to Target; 2019 Jan 15-18; Houston, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(19 Suppl):Abstract nr B13.