Publications by authors named "Melissa M Ronan"

KRASG12C selective inhibitors, such as sotorasib and adagrasib, have raised hopes of targeting other KRAS mutant alleles in cancer patients. We report that KRAS wild-type amplified tumor models are sensitive to treatment with the small molecule KRAS inhibitors BI-2493 and BI-2865. These pan-KRAS inhibitors directly target the "OFF" state of KRAS and result in potent anti-tumor activity in pre-clinical models of cancers driven by KRAS mutant proteins.

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One of the most robust synthetic lethal interactions observed in multiple functional genomic screens has been the dependency on protein arginine methyltransferase 5 (PRMT5) in cancer cells with MTAP deletion. We report the discovery of the clinical stage MTA-cooperative PRMT5 inhibitor AMG 193, which preferentially binds PRMT5 in the presence of MTA and has potent biochemical and cellular activity in MTAP-deleted cells across multiple cancer lineages. In vitro, PRMT5 inhibition induces DNA damage, cell cycle arrest, and aberrant alternative mRNA splicing in MTAP-deleted cells.

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Aberrant DNA repair is a hallmark of cancer, and many tumors display reduced DNA repair capacities that sensitize them to genotoxins. Here, we demonstrate that the differential DNA repair capacities of healthy and transformed tissue may be exploited to obtain highly selective chemotherapies. We show that the novel N3-(2-fluoroethyl)imidazotetrazine "KL-50" is a selective toxin toward tumors that lack the DNA repair protein O-methylguanine-DNA-methyltransferase (MGMT), which reverses the formation of O-alkylguanine lesions.

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Transcription factors (TFs) are important mediators of aberrant transcriptional programs in cancer cells. In this study, we focus on TF activity (TFa) as a biomarker for cell-line-selective anti-proliferative effects, in that high TFa predicts sensitivity to loss of function of a given gene (i.e.

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Broad-spectrum RAS inhibition has the potential to benefit roughly a quarter of human patients with cancer whose tumours are driven by RAS mutations. RMC-7977 is a highly selective inhibitor of the active GTP-bound forms of KRAS, HRAS and NRAS, with affinity for both mutant and wild-type variants. More than 90% of cases of human pancreatic ductal adenocarcinoma (PDAC) are driven by activating mutations in KRAS.

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Unlabelled: Medulloblastoma is one of the most common malignant brain tumors of children, and 30% of medulloblastomas are driven by gain-of-function genetic lesions in the Sonic Hedgehog (SHH) signaling pathway. EYA1, a haloacid dehalogenase phosphatase and transcription factor, is critical for tumorigenesis and proliferation of SHH medulloblastoma (SHH-MB). Benzarone and benzbromarone have been identified as allosteric inhibitors of EYA proteins.

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Citron kinase (CITK) is an AGC-family serine/threonine kinase that regulates cytokinesis. Despite knockdown experiments implicating CITK as an anticancer target, no selective CITK inhibitors exist. We transformed a previously reported kinase inhibitor with weak off-target CITK activity into a first-in-class CITK chemical probe, .

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Article Synopsis
  • Chromosomal instability (CIN) is a common feature in aggressive cancers, such as high-grade serous ovarian cancer (HGSOC) and triple-negative breast cancer (TNBC), often linked to TP53 mutations.
  • Researchers discovered that KIF18A motor protein inhibitors can activate the mitotic checkpoint, causing selective death of cancer cells with CIN, especially those with TP53 mutations.
  • These inhibitors demonstrated minimal side effects on normal human bone marrow cells and showed significant tumor regression in HGSOC and TNBC models in mice, suggesting a promising targeted therapy for CIN-associated cancers.
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Article Synopsis
  • Scientists found that blocking RAS, a gene that can cause cancer when mutated, might help about 25% of cancer patients.
  • They tested a drug called RMC-7977 on various cancer models, especially pancreatic cancer, and saw it stopped tumors from growing without harming normal tissue.
  • The drug caused cancer cells to die off, but normal cells only slowed down a bit, showing it could be a good option for treating pancreatic cancer.
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Anticancer nucleosides are effective against solid tumors and hematologic malignancies, but typically are prone to nucleoside metabolism resistance mechanisms. Using a nucleoside-specific multiplexed high-throughput screening approach, we discovered 4'-ethynyl-2'-deoxycytidine (EdC) as a third-generation anticancer nucleoside prodrug with preferential activity against diffuse large B-cell lymphoma (DLBCL) and acute lymphoblastic leukemia (ALL). EdC requires deoxycytidine kinase (DCK) phosphorylation for its activity and induces replication fork arrest and accumulation of cells in S-phase, indicating it acts as a chain terminator.

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The histone lysine demethylases KDM4A-C are involved in physiologic processes including stem cell identity and self-renewal during development, DNA damage repair, and cell-cycle progression. KDM4A-C are overexpressed and associated with malignant cell behavior in multiple human cancers and are therefore potential therapeutic targets. Given the role of KDM4A-C in development and cancer, we aimed to test the potent, selective KDM4A-C inhibitor QC6352 on oncogenic cells of renal embryonic lineage.

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NADPH oxidases (NOXs) are transmembrane enzymes that are devoted to the production of reactive oxygen species (ROS). In cancers, dysregulation of NOX enzymes affects ROS production, leading to redox unbalance and tumor progression. Consequently, NOXs are a drug target for cancer therapeutics, although current therapies have off-target effects: there is a need for isoenzyme-selective inhibitors.

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Transcriptional enhanced associate domain (TEAD) proteins together with their transcriptional coactivator yes-associated protein (YAP) and transcriptional coactivator with the PDZ-binding motif (TAZ) are important transcription factors and cofactors that regulate gene expression in the Hippo pathway. In mammals, the TEAD families have four homologues: TEAD1 (TEF-1), TEAD2 (TEF-4), TEAD3 (TEF-5), and TEAD4 (TEF-3). Aberrant expression and hyperactivation of TEAD/YAP signaling have been implicated in a variety of malignancies.

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Article Synopsis
  • TEAD and YAP/TAZ are important proteins that help control gene activity and are linked to some types of cancer, making them good targets for new drugs.
  • Scientists faced challenges in designing small drugs to affect TEAD, but they found a way to create a special drug called MYF-03-69 that binds to TEAD effectively and stops cancer growth.
  • Further development led to a stronger version of the drug, MYF-03-176, which was successful in stopping tumors in mice and shows promise for treating cancers related to TEAD and YAP.
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  • Scientists are looking at a protein called ERK5 to see how it affects diseases like cancer and inflammation.
  • They tried using a drug to stop ERK5 from working, but it didn’t have the same effects as removing it completely, which means ERK5 might have other important jobs.
  • Researchers created a new tool called INY-06-061 to study ERK5 better, but this tool also didn’t do what they expected when they tested it on cancer cells and inflammation.
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Cyclin-dependent kinases 4 and 6 (CDK4/6) represent a major therapeutic vulnerability for breast cancer. The kinases are clinically targeted via ATP competitive inhibitors (CDK4/6i); however, drug resistance commonly emerges over time. To understand CDK4/6i resistance, we surveyed over 1,300 breast cancers and identified several genetic alterations (e.

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