bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 2955: SMYD2 regulates chromatin modifier KMT2D in ER+/PIK3CA mutant breast cancer
Authors: Blawski Ryan , Sallaku Mirna , Guo Xinyu , Kittane Srushti , Scaltriti Maurizio , Luo Minkui , Toska Eneda 
Published: June 2022

Abstract
Breast cancer leads current cancer diagnoses worldwide, accounting for 1 in 4 cancer cases and 1 in 6 cancer deaths in women. Over 70% of breast tumors are hormone receptor positive and can be treated with endocrine therapy, however tumor recurrence remains a major obstacle. Oncogenic mutations in the catalytic subunit of PI3K occur in up to 40% of ER+/HER2- negative breast tumors, making it a promising therapeutic target. Clinically, PI3K inhibitors have shown limited efficacy as monotherapy due to a number of resistance mechanisms, including an upregulation of ER-dependent signaling. Identification of the ER-PI3K signaling crosstalk led to clinical trials which resulted in the approval of the PI3K inhibitor alpelisib in combination with fulvestrant in patients with hormone-refractory ER+/PIK3CA-mutant breast cancer. Further work uncovered a key role for the chromatin modifier KMT2D in regulating ER-dependent transcription upon PI3K inhibition. PI3K effectors AKT1/SGK1 negatively regulate KMT2D through direct S1331 phosphorylation. When PI3K is inhibited, this downstream regulatory event is lost, leading to increased chromatin recruitment of KMT2D and an upregulation of ER-dependent transcription. We have identified a novel methylation site on KMT2D, at K1330 directly adjacent to S1331, catalyzed by the lysine methyltransferase SMYD2. Knockdown of SMYD2 sensitizes ER+/PIK3CA mutant breast cancer cell lines to PI3K inhibition. The combination of SMYD2 knockdown and alpelisib leads to a significant reduction in tumor growth compared to alpelisib alone in a xenograft model. Mechanistically, SMYD2 knockdown is able to attenuate alpelisib-induced KMT2D chromatin binding globally and at ER loci. Accordingly, loss of SMYD2 abrogates alpelisib-induced changes in gene expression, including ER-dependent transcription. Altogether our results demonstrate a role for epigenetic therapy using SMYD2 inhibitors in combination with alpelisib for the treatment of ER+/PIK3CA mutant breast cancer.
Citation Format: Ryan Blawski, Mirna Sallaku, Xinyu Guo, Srushti Kittane, Maurizio Scaltriti, Minkui Luo, Eneda Toska. SMYD2 regulates chromatin modifier KMT2D in ER+/PIK3CA mutant breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2955.
Abstract 2958: Chromatin repressor complex as a converge point of RAS and PP2A activities in lung cancer
Authors: Sharma Mukund , Aakula Anna , Tabaro Francesco , Pavic Karolina , Huhtaniemi Riikka , Nykter Matti , Westermarck Jukka 
Published: June 2022

Abstract
Protein phosphatase 2A (PP2A) is a tumor suppressor while RAS proteins are potent oncogenes in different cancer types. It is well established that RAS-mediated oncogenic transformation requires simultaneous inhibition of PP2A, but the molecular basis of their interaction is poorly understood. To address the target mechanisms co-regulated by RAS and PP2A we performed a phosphoproteomics screen upon RAS or PP2A manipulation. Overall the results indicated that RAS and PP2A regulate overlapping cellular processes, and that their activities might in particular converge at epigenetic machineries.
To study the RAS and PP2A synergy on transcriptional and epigenome regulation we performed multi-omics analysis of cancer cells in which RAS and PP2A activities were modulated. PP2A inhibition resulted in global gene activation while RAS inhibition lead predominantly to gene repression. Use of GFP reporter indicative of epigenetic silencing further confirmed the role of PP2A as a transcriptional repressor and RAS as a transcriptional activator. To investigate the DNA methylation changes and chromatin remodeling effects upon PP2A modulation we used RRBS (Reduced representation bisulfite sequencing) & ATAC-seq (Assay for Transposase-Accessible Chromatin using sequencing) respectively. PP2A inhibition resulted in global DNA hypomethylation and an open state of chromatin confirming its role as a global repressor of epigenetic processes.
To delineate the molecular mechanism behind the transcriptional regulation by RAS and PP2A we monitored the chromatin recruitment of transcriptional repressors upon PP2A or RAS manipulation. Either pharmacological or siRNA mediated PP2A or RAS modulation significantly affected gene repressor complex recruitment to the chromatin. Role of phosphorylation as a critical switch for chromatin repressor complex recruitment was demonstrated by CRISPR/Cas9-mediated mutagenesis of PP2A target phosphorylation site, which also led to a clear phenotype in in vivo tumorigenesis and oncogenic transcription.
Collectively these results identify a novel phosphorylation switch on chromatin repressor complex as a converge point of KRAS and PP2A activities in lung cancer. Generally the results provide first indications to global importance of PP2A-mediated phosphorylation regulation in epigenetic gene regulation in cancer.
Citation Format: Mukund Sharma, Anna Aakula, Francesco Tabaro, Karolina Pavic, Riikka Huhtaniemi, Matti Nykter, Jukka Westermarck. Chromatin repressor complex as a converge point of RAS and PP2A activities in lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2958.
Abstract 2959: Investigating the oncogenic effects and mechanisms of the SMYD3 methyltransferase in HPV-negative head and neck squamous cell carcinoma
Authors: Murali Madhavi , Tsai Daniel , Nigam Nupur , Burkitt Kyunghee , Kim Sohyoung , Cheng Hui , Saloura Vassiliki 
Published: June 2022

Abstract
Human papillomavirus (HPV)-negative head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer type in the world and is associated with an overall poor prognosis. The protein methyltransferase SET and MYND domain-containing 3 (SMYD3), which trimethylates H3K4 and H4K20, can stimulate gene transcription and activate several oncogenic pathways, including epithelial-mesenchymal transition, and cell cycle related pathways. Additionally, its expression is associated with a poor prognosis in various cancer types, such as colon and ovarian cancer. This study aims to decipher whether SMYD3 has direct oncogenic effects and relevant mechanisms in HPV-negative HNSCC. Our preliminary results have demonstrated that SMYD3 is significantly overexpressed in HPV-negative HNSCC compared to normal and dysplastic epithelium. SMYD3 knockdown decreased cellular proliferation and clonal capacity in CFAs after siRNA-mediated SMYD3 knockdown in several HPV-negative HNSCC cell lines or CRISPR-mediated SMYD3 knockout. Cell cycle analysis of CRISPR SMYD3 KO cell lines showed a significant decrease in the S phase, supporting that cell cycle arrest may be a mechanism through which this decreased cellular proliferation occurs. Nuclear/cytoplasmic dissociation and western blotting of 6 HPV-negative HNSCC cell lines, and immunohistochemistry for SMYD3 in primary and recurrent/metastatic HPV-negative HNSCC tumor tissues have identified the expression of SMYD3 in both the cytoplasm and nucleus, with greater expression in the cytoplasm than the nucleus. Ongoing experiments aim to investigate the effects of SMYD3 knockdown on the global proteome, as well as its effects on histone post-translational modifications in HPV-negative HNSCC cell lines. Genome-wide mapping for SMYD3, H3K4me3 and H4K20me3 in HPV- negative HNSCC cells using CUT&RUN assays are ongoing with the goal to identify direct downstream gene targets regulated by human SMYD3. Finally, we plan to investigate if SMYD3 knockout decreases tumor growth in NSG xenografts. This study may provide the biological rational to target SMYD3 as a novel therapeutic avenue in HPV-negative HNSCC.
Citation Format: Madhavi Murali, Daniel Tsai, Nupur Nigam, Kyunghee Burkitt, Sohyoung Kim, Hui Cheng, Vassiliki Saloura. Investigating the oncogenic effects and mechanisms of the SMYD3 methyltransferase in HPV-negative head and neck squamous cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2959.
Abstract 2970: Oncometabolites confer vulnerabilities in NAD biosynthesis via NAPRT gene silencing
Authors: Noronha Katelyn , Liang Jiayu , Bindra Ranjit 
Published: June 2022

Abstract
Cancer associated mutations in citric acid cycle enzymes cause overproduction of 2-hydroxyglutarate (2HG), fumarate, or succinate, commonly referred to as oncometabolites. These oncometabolite producing mutations are prevalent in 70% of gliomas, &gt;76% of hereditary leiomyomatosis and renal cell carcinoma, and &gt;25% of paraganglioma and pheochromocytomas, respectively. These oncometabolite producing cancers harbor vulnerabilities in multiple cellular pathways because oncometabolites competitively inhibit alpha ketoglutarate dependent dioxygenases. This group of enzymes includes the ten eleven translocation (TET) family of enzymes, which catalyze locus specific DNA demethylation. Thus, oncometabolite producing cancers have been shown to exhibit global DNA hypermethylation, which drastically alters gene expression in the cell and is thought to occur via TET inhibition. Cells with isocitrate dehydrogenase 1 (IDH1) mutations, which produce 2HG, have loss of expression of a critical NAD biosynthesis enzyme, nicotinate phosphoribosyltransferase (NAPRT). We show that in addition to IDH1 mutant cells, fumarate hydratase (FH)-deficient isogenic cell lines, which overproduce fumarate, show loss of NAPRT expression, which can be targeted by nicotinamide phosphoribosyltransferase (NAMPT) inhibitors. The goal of our work is to determine if this NAPRT silencing is present in many oncometabolite producing cancers, elucidate the mechanism of silencing, and test therapies to target this vulnerability in NAD biosynthesis. FH-deficient cancer cell lines show reduction of NAPRT mRNA levels by qRT-PCR and absence of protein by western blot, suggesting a reduction in NAPRT transcription. In addition, FH-deficient cell lines exhibit synthetic lethality in short term cell viability assays when treated with NAMPT inhibitor, FK866, which inhibits a parallel NAD biosynthesis pathway. Cell viability is not rescued by nicotinic acid supplementation in FH-deficient lines while parental lines are rescuable, validating the loss of functional NAPRT in only FH-deficient lines. Furthermore, patient samples of FH-deficient renal cell carcinomas show higher NAPRT promoter methylation compared to healthy tissue via methylation array. Ongoing studies are investigating the role of TET1/2/3 enzymes in NAPRT promoter methylation. Together, these results suggest that hypermethylation of the NAPRT promoter is associated with silencing of NAPRT expression in FH-deficient cancers, which can be therapeutically targeted through NAMPT inhibition.
Citation Format: Katelyn Noronha, Jiayu Liang, Ranjit Bindra. Oncometabolites confer vulnerabilities in NAD biosynthesis via NAPRT gene silencing [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2970.
Abstract 2977: Profiling oncogenic Ras mutant drugs with homogeneous bioluminescent immunoassays
Authors: Zegzouti Hicham , Engel Laurie , Swiatnicki Matthew , Alves Juliano , Goueli Said A. 
Published: June 2022

Abstract
Activating KRAS mutations present in many cancers are difficult to target with drugs until recently with the FDA approval of sotorasib (AMG-510), a KRAS G12C selective inhibitor. In an effort to study Ras inhibitors in cells and identify new compounds that inhibit Ras and its downstream signaling, assays such as western or ELISA are commonly used. These traditional immunoassays can be tedious, require multiple washing steps, and are not easily adaptable to a high throughput screening (HTS) format. To overcome these limitations, we developed Lumit, a novel immunoassay approach that combines bioluminescent enzyme subunit complementation technology and immunodetection. We applied this bioluminescent and homogeneous “Add and Read” assay to analyze Ras signaling pathway activation and inhibition through multiple nodes of the pathway including detection of phosphorylated ERK. The assay was used to profile different allele specific inhibitors with cell lines harboring different activating KRAS mutations and obtained the predicted pharmacology and selectivity. The potency of PROTAC compound targeting selective degradation of KRAS G12C was also tested using Lumit and the result showed that maximal decrease in RAS signaling was achieved. Unlike current assays that require lengthy sample preparation and multiple washing steps, the Lumit immunoassay provides an alternative platform because it is homogeneous and allows to decipher signaling pathways activities in a fast and simple manner. Our results demonstrate that this bioluminescent technology can be adapted to any signaling pathway node, allowing scientists to streamline the analysis of signaling pathways of interest such as Ras, and identify much needed inhibitors of its mutants.
Citation Format: Hicham Zegzouti, Laurie Engel, Matthew Swiatnicki, Juliano Alves, Said A. Goueli. Profiling oncogenic Ras mutant drugs with homogeneous bioluminescent immunoassays [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2977.
Abstract 2981: Loss of the small GTPase RHOA enhances lymphomagenesis and impairs the activity of lenalidomide in mantle cell lymphoma
Authors: Santos Juliana C. , Ribeiro Marcelo L. , Roue Gael 
Published: June 2022

Abstract
The small GTPase Ras homolog family member A (RHOA) is one of the most extensively investigated members of the Rho GTPase family, that acts as a molecular switch controlling a wide variety of signal transduction pathways. Although RHOA has long been implicated in malignant transformation in solid tumors, recent evidences have demonstrated its tumor suppressor activity in different subgroups of B-cell non-Hodgkin lymphoma (B-NHL). Here, using a panel of 11 cell lines covering the most common and/or aggressive B-NHL subtypes, we observed that the lowest mRNA and protein levels of RHOA are found in mantle cell lymphoma (MCL), the most aggressive entity with a median overall survival of 5-7 years. Depletion of RHOA expression and activity was carried out in the two RHOA+ MCL cell lines, REC-1 and Z-138, by CRISPR/Cas9-mediated gene edition followed by RHOA pulldown activation assay. In RHOA knockout (KO) subclones, cell proliferation was increased by 40%, in association with a 10-fold increase in mitotic index and a 3-fold potentiation of cell migration, as assessed respectively by CellTitter-Glo assay, histone H3-pSer10 labeling and Transwell assay, thus suggesting a tumor suppressor role of RHOA in MCL malignancy. Comparative RNA-seq analysis of RHOAWT and RHOAKO MCL subclones then highlighted a crucial role of RHOA and its downstream signaling in the control of MCL cell proliferation, cell cycle and cell migration. Interestingly, the immunomodulatory drug lenalidomide has previously shown to regulate such processes and to be clinically active in patients with relapsed/refractory MCL. In a co-culture system associating RHOAWT MCL cells with peripheral blood-derived effector cells, we observed that lenalidomide treatment facilitated the formation of immunological synapse, as revealed by simultaneous immunodetection of effector T cells, target B cells and perforin, and by quantification of lactate dehydrogenase (LDH) release. Conversely, lenalidomide exhibited minimal effect in the RHOAKO MCL co-cultures, as shown by a 30-40% decrease in the formation of immune synapse and a 4-fold decrease in LDH secretion. Taken together, these data provide the first insight into the tumor suppressive activity of RHOA in MCL and into its requirement for the immune-mediated mechanism of action of lenalidomide in this disease. Ongoing in vivo validation studies will be presented.
Citation Format: Juliana C. Santos, Marcelo L. Ribeiro, Gael Roue. Loss of the small GTPase RHOA enhances lymphomagenesis and impairs the activity of lenalidomide in mantle cell lymphoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2981.
Abstract 2987: A versatile assay suite for the discovery of new KRAS pathway inhibitors
Authors: Kouznetsova Ekaterina , McCauley Lauren , Steinke-Neal Elaine , Sullivan Timothy , Primavera Louis , Eells Rebecca , Ma Haiching 
Published: June 2022

Abstract
The small GTPase, KRAS, is a known oncogene and a desirable drug target due to prevalence of mutations with poor disease prognosis. The absence of good druggable binding pockets has made modulator compound discovery challenging and unsuccessful. Identification of new inhibitor target sites has led to the resurgence of interest in KRAS drug discovery. To facilitate drug discovery activities targeting KRAS/MAPK pathway, we have produced the full spectrum of pathway proteins including kinases, wild type and mutated KRAS, guanine nucleotide exchange factor and effectors. This poster will summarize our most recent assay development efforts for biochemical and biophysical assays for these targets.
Citation Format: Ekaterina Kouznetsova, Lauren McCauley, Elaine Steinke-Neal, Timothy Sullivan, Louis Primavera, Rebecca Eells, Haiching Ma. A versatile assay suite for the discovery of new KRAS pathway inhibitors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2987.
Abstract 299: Self-assembling nanoparticles: A novel approach for targeted cancer treatment using tumor treating fields
Authors: Desai Preshita Prafulla , Prabhu Sunil 
Published: June 2022

Abstract
Tumor Treating Fields (TTFields) are used in cancer treatment as they offer increased efficacy, safety, and low adverse effects. They have shown significant potential in pancreatic cancer (PC) clinical trials when combined with chemotherapy. It is pertinent to know that although TTFields-chemotherapy combination definitely enhances the treatment efficacy, it also results in chemotherapy induced severe adverse effects. To resolve this, we earlier reported development of Gemcitabine loaded self-assembling cationic-anionic polymer nanoparticles (S-CAP NPs) capable of achieving TTFields-triggered targeted drug release at the PC tumor site. Initially, four S-CAP NPs [C4 and C7 from chitosan- bovine serum albumin (Chitosan-BSA) S-CAP NPs; P5 and P8 from polyethylenimine- bovine serum albumin (PEI-BSA) S-CAP NPs] were shortlisted [Table 1 - particle size: ~ 200 nm; % encapsulation efficiency (EE): 55-65%]. For proof-of-concept studies, effect of TTFields on the % EE and % cumulative drug release of the S-CAP-NPs was investigated. The studies revealed (Table 1) significant reduction (p value &lt; 0.05) in the % EE of S-CAP NPs within 48h TTFields treatment, confirming that the TTFields destabilize the NPs triggering targeted drug release. Similarly, In vitro drug release studies showed significant increase (p&lt; 0.01) in rate of drug release from S-Cap NPs in presence of TTFields. The cell inhibition assay confirmed the synergism in cell apoptosis wherein PEI-BSA S-CAP NPs showed higher efficacy compared to chitosan-BSA S-CAP NPs. Further, additional stability studies continued over a period of 18 months confirmed stable formulations. In vivo acute and chronic toxicity studies are underway to identify the most optimum dose of S-CAP NPs for further in vivo efficacy studies. To summarize, S-CAP-NPs present a promising avenue to achieve targeted chemotherapy in conjunction with TTFields. This work is supported by AACR-Novocure tumor treating fields research fellowship.
Table 1. Effect of TTFields on % encapsulation efficiency (n=3). Data represented as Mean ± SD. Batch Particle size (nm) Encapsulation efficiency (%) - 0h Encapsulation efficiency (%) - 24h - 150 KHZ Encapsulation efficiency (%) - 48h - 150 KHZ Chitosan-BSA S-CAP NPs C4 210.54 ± 38.96 61.26 ± 5.11 36.21 ± 3.53 24.86 ± 3.19 C7 215.67 ± 32.55 65.31 ± 5.84 32.19 ± 2.68 21.86 ± 4.64 PEI-BSA S-CAP NPs P5 198.29 ± 41.05 58.83 ± 3.33 27.66 ± 3.31 18.96 ± 3.96 P8 209.92 ± 31.33 64.31 ± 5.13 24.83 ± 4.29 19.42 ± 2.73
Citation Format: Preshita Prafulla Desai, Sunil Prabhu. Self-assembling nanoparticles: A novel approach for targeted cancer treatment using tumor treating fields [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 299.
Abstract 2990: Role of CCR6-CCL20 chemokine axis in colon cancer
Authors: Brock Briana A. , Singh Shailesh , Mir Hina A. 
Published: June 2022

Abstract
Colon cancer remains the third leading cause of cancer-related deaths because chemotherapeutics currently offered to treat early, and advanced colon cancer fail to achieve optimal clinical response. Therefore, development of more efficacious treatment option is crucial to improve clinical outcomes. We have used TCGA and CPTAC analysis from UALCAN data base for the expression of CCR6 and CCL20 in colon cancer tissue compared to adjacent normal. RT-qPCR and proteomics approach were used for analysis of CCR6 and CCL20 expression in colon cancer cell lines. Our data shows higher expression of CCR6 and its ligand CCL20 in colon cancer tissue and cell lines. We further investigated involvement of CCR6/CCL20 on therapeutic response of 5-Fluorouracil and Oxaliplatin commonly used to treat colon cancer. Our data suggest that colon cancer cell lines respond poorly to 5-Fluorouracil and Oxaliplatin when treated with CCL20 and blocking CCR6 with anti-CCR6 improves cytotoxic effect of 5-Fluorouracil and Oxaliplatin. Poor response to chemotherapeutic after CCR6 activation was primarily due to activation molecular and cellular phenotypes and alteration in cell cycle. In conclusion, our data suggest that CCR6/CCL20 promotes colon cancer progression and CCR6-mediates signals contributed to poor response to conventional therapeutic such as 5-Fluorouracil and Oxaliplatin. Hence, targeting CCR6 in early stage will prevent metastasis, enhance therapeutic efficacy and reduce toxicity and will be a promising approach to improve clinical outcome.
Citation Format: Briana A. Brock, Shailesh Singh, Hina A. Mir. Role of CCR6-CCL20 chemokine axis in colon cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2990.