Discovery and Optimization of Pyrrolopyrimidine Derivatives as Selective Disruptors of the Perinucleolar Compartment, a Marker of Tumor Progression toward Metastasis

This document is the Accepted Manuscript version of a Published Work that appeared in final form in Journal of Medicinal Chemistry, Copyright © 2022 American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acs.jmedchem.2c00204.The perinucleolar compartment (PNC) is a dynamic subnuclear body found at the periphery of the nucleolus. The PNC is enriched with RNA transcripts and RNA-binding proteins, reflecting different states of genome organization. PNC prevalence positively correlates with cancer progression and metastatic capacity, making it a useful marker for metastatic cancer progression. A high-throughput, high-content assay was developed to identify novel small molecules that selectively reduce PNC prevalence in cancer cells. We identified and further optimized a pyrrolopyrimidine series able to reduce PNC prevalence in PC3M cancer cells at submicromolar concentrations without affecting cell viability. Structure–activity relationship exploration of the structural elements necessary for activity resulted in the discovery of several potent compounds. Analysis of in vitro drug-like properties led to the discovery of the bioavailable analogue, metarrestin, which has shown potent antimetastatic activity with improved survival in rodent models and is currently being evaluated in a first-in-human phase 1 clinical trial

Functional loss of IKBE leads to NF-KB deregulation in aggressive chronic lymphocytic leukemia

NF-?B is constitutively activated in chronic lymphocytic leukemia (CLL); however, the implicated molecular mechanisms remain largely unknown. Thus, we performed targeted deep sequencing of 18 core complex genes within the NF-?B pathway in a discovery and validation CLL cohort totaling 315 cases. The most frequently mutated gene was NFKBIE (21/315 cases; 7%), which encodes I?B?, a negative regulator of NF-?B in normal B cells. Strikingly, 13 of these cases carried an identical 4-bp frameshift deletion, resulting in a truncated protein. Screening of an additional 377 CLL cases revealed that NFKBIE aberrations predominated in poor-prognostic patients and were associated with inferior outcome. Minor subclones and/or clonal evolution were also observed, thus potentially linking this recurrent event to disease progression. Compared with wild-type patients, NFKBIE-deleted cases showed reduced I?B? protein levels and decreased p65 inhibition, along with increased phosphorylation and nuclear translocation of p65. Considering the central role of B cell receptor (BcR) signaling in CLL pathobiology, it is notable that I?B? loss was enriched in aggressive cases with distinctive stereotyped BcR, likely contributing to their poor prognosis, and leading to an altered response to BcR inhibitors. Because NFKBIE deletions were observed in several other B cell lymphomas, our findings suggest a novel common mechanism of NF-?B deregulation during lymphomagenesis. <br/

Generation of high-throughput three dimensional tumor spheroids for drug screening

Cancer cells have routinely been cultured in 2-dimensions (2D) on a plastic surface. This technique, however, lacks the true environment a tumor mass is exposed to in vivo. Solid tumors grow not as a sheet attached to plastic, but instead as aggregated cells in three dimensions interacting with their neighbors, and with distinct spatial properties such as polarity. These interactions cause the three dimensional (3D) cultured cells to acquire morphological and cellular characteristics which are more relevant to in vivo tumors1. Additionally, a tumor mass is in direct contact with other cell types such as stromal and immune cells, as well as extracellular matrix from all other cell types. The matrix which is deposited is comprised of macro-molecules such as collagen and fibronectin. In an attempt to increase the translation of research findings in oncology from the bench to the bedside many groups have started to investigate the use of three dimensional (3D) model systems in their drug development strategies. These systems are thought to be more physiologically relevant because they attempt to recapitulate the complex and heterogeneous environment of a tumor1 These systems, however, can be quite complex, and although amenable to growth in 96-well formats, and some now even in 384, offer few choices for large scale growth and screening. This observed gap has led to the development of the methods described here in detail to culture tumor spheroids in a high throughput capacity in 1536-well plates. A variety of cancer cell lines were successfully screened examining compound efficacy using a curated library of compounds targeting the MAPK pathway. The spheroid culture responses were then compared to the response of cells grown in 2D and differential activities are reported. These methods provide a unique protocol for testing compound activity in a high-throughput 3D setting

Mitella pauciflora Rosend.

原著和名: コチャルメルサウ科名: ユキノシタ科 = Saxifragaceae採集地: 高知県 吾川郡 池川町 (土佐 吾川郡 池川町)採集日: 1979/3/27採集者: 萩庭丈壽整理番号: JH000809国立科学博物館整理番号: TNS-VS-95080

Design and Discovery of N-(3-(2-(2-hydroxyethoxy)-6-morpholinopyridin-4-yl)-4-methylphenyl)-2-(trifluoromethyl)isonicotinamide (LXH254), A selective, efficacious, well-tolerated RAF inhibitor targeting RAS mutant cancers: The path to the clinic

RAS and BRAF oncogenes are mutated in more than one-third of human cancers and exquisite dependency on CRAF, MEK1/2 and ERK1/2 has been demonstrated in preclinical models of RAS mutant cancer. Direct pharmacological inhibition of RAS has remained elusive and efforts to target CRAF have been challenging due to the nature of the RAF signaling complex downstream of activated RAS and the poor overall kinase selectivity profile of putative RAF inhibitors such as sorafenib and RAF265. Herein, we describe 15 (LXH254), a selective B/C RAF inhibitor, which has been developed through a hypothesis-driven approach focusing on drug-like properties. We have previously disclosed the discovery of 3 (RAF709), a preclinical tool compound which was potent, selective, efficacious, and well-tolerated in preclinical models, but the high intrinsic clearance [HLM Cl(int) = 94] precluded further development.X The high clearance of 3 by HLM prompted the medicinal chemistry team to further investigate close analogs as well as novel scaffolds. While keeping drug-like properties in mind, the team identified multiple cell-potent scaffolds with low-to-moderate human clearance and progressed them into in-vivo pharmacology studies. Unexpectedly, the majority of novel scaffolds caused significant body weight loss in mice for unknown reasons, with the 2-pyridine series emerging as the only scaffold which was not plagued by this problem. A structure-based approach led to the realization that an alcohol side-chain in the 2-position of the pyridine could interact with the DFG loop and significantly improve cell potency. Further mitigation of human intrinsic clearance and time-dependent inhibition of CYP3A4 (TDI) led to the discovery of 15, which had favorable PK and proved to be efficacious in multiple xenograft models such as Calu-6 (KRASQ61K),with a favorable therapeutic index. Due to its excellent in vitro/ in vivo properties, it has progressed through preclinical toxicology studies and now being tested as a single agent and as a combination partner in phase 1 clinical trial

Efficacy and Mechanism of Action of Low Dose Emetine against Human Cytomegalovirus.

Infection with human cytomegalovirus (HCMV) is a threat for pregnant women and immunocompromised hosts. Although limited drugs are available, development of new agents against HCMV is desired. Through screening of the LOPAC library, we identified emetine as HCMV inhibitor. Additional studies confirmed its anti-HCMV activities in human foreskin fibroblasts: EC50-40±1.72 nM, CC50-8±0.56 μM, and selectivity index of 200. HCMV inhibition occurred after virus entry, but before DNA replication, and resulted in decreased expression of viral proteins. Synergistic virus inhibition was achieved when emetine was combined with ganciclovir. In a mouse CMV (MCMV) model, emetine was well-tolerated, displayed long half-life, preferential distribution to tissues over plasma, and effectively suppressed MCMV. Since the in vitro anti-HCMV activity of emetine decreased significantly in low-density cells, a mechanism involving cell cycle regulation was suspected. HCMV inhibition by emetine depended on ribosomal processing S14 (RPS14) binding to MDM2, leading to disruption of HCMV-induced MDM2-p53 and MDM2-IE2 interactions. Irrespective of cell density, emetine induced RPS14 translocation into the nucleus during infection. In infected high-density cells, MDM2 was available for interaction with RPS14, resulting in disruption of MDM2-p53 interaction. However, in low-density cells the pre-existing interaction of MDM2-p53 could not be disrupted, and RPS14 could not interact with MDM2. In high-density cells the interaction of MDM2-RPS14 resulted in ubiquitination and degradation of RPS14, which was not observed in low-density cells. In infected-only or in non-infected emetine-treated cells, RPS14 failed to translocate into the nucleus, hence could not interact with MDM2, and was not ubiquitinated. HCMV replicated similarly in RPS14 knockdown or control cells, but emetine did not inhibit virus replication in the former cell line. The interaction of MDM2-p53 was maintained in infected RPS14 knockdown cells despite emetine treatment, confirming a unique mechanism by which emetine exploits RPS14 to disrupt MDM2-p53 interaction. Summarized, emetine may represent a promising candidate for HCMV therapy alone or in combination with ganciclovir through a novel host-dependent mechanism