Translational and Therapeutic Evaluation of RAS-GTP Inhibition by RMC-6236 in RAS-Driven Cancers.

RAS-driven cancers comprise up to 30% of human cancers. RMC-6236 is a RAS(ON) multi-selective noncovalent inhibitor of the active, GTP-bound state of both mutant and wild-type variants of canonical RAS isoforms with broad therapeutic potential for the aforementioned unmet medical need. RMC-6236 exhibited potent anticancer activity across RAS-addicted cell lines, particularly those harboring mutations at codon 12 of KRAS. Notably, oral administration of RMC-6236 was tolerated in vivo and drove profound tumor regressions across multiple tumor types in a mouse clinical trial with KRASG12X xenograft models. Translational PK/efficacy and PK/PD modeling predicted that daily doses of 100 mg and 300 mg would achieve tumor control and objective responses, respectively, in patients with RAS-driven tumors. Consistent with this, we describe here objective responses in two patients (at 300 mg daily) with advanced KRASG12X lung and pancreatic adenocarcinoma, respectively, demonstrating the initial activity of RMC-6236 in an ongoing phase I/Ib clinical trial (NCT05379985). SIGNIFICANCE: The discovery of RMC-6236 enables the first-ever therapeutic evaluation of targeted and concurrent inhibition of canonical mutant and wild-type RAS-GTP in RAS-driven cancers. We demonstrate that broad-spectrum RAS-GTP inhibition is tolerable at exposures that induce profound tumor regressions in preclinical models of, and in patients with, such tumors. This article is featured in Selected Articles from This Issue, p. 897.

Concurrent inhibition of oncogenic and wild-type RAS-GTP for cancer therapy.

RAS oncogenes (collectively NRAS, HRAS and especially KRAS) are among the most frequently mutated genes in cancer, with common driver mutations occurring at codons 12, 13 and 611. Small molecule inhibitors of the KRAS(G12C) oncoprotein have demonstrated clinical efficacy in patients with multiple cancer types and have led to regulatory approvals for the treatment of non-small cell lung cancer2,3. Nevertheless, KRASG12C mutations account for only around 15% of KRAS-mutated cancers4,5, and there are no approved KRAS inhibitors for the majority of patients with tumours containing other common KRAS mutations. Here we describe RMC-7977, a reversible, tri-complex RAS inhibitor with broad-spectrum activity for the active state of both mutant and wild-type KRAS, NRAS and HRAS variants (a RAS(ON) multi-selective inhibitor). Preclinically, RMC-7977 demonstrated potent activity against RAS-addicted tumours carrying various RAS genotypes, particularly against cancer models with KRAS codon 12 mutations (KRASG12X). Treatment with RMC-7977 led to tumour regression and was well tolerated in diverse RAS-addicted preclinical cancer models. Additionally, RMC-7977 inhibited the growth of KRASG12C cancer models that are resistant to KRAS(G12C) inhibitors owing to restoration of RAS pathway signalling. Thus, RAS(ON) multi-selective inhibitors can target multiple oncogenic and wild-type RAS isoforms and have the potential to treat a wide range of RAS-addicted cancers with high unmet clinical need. A related RAS(ON) multi-selective inhibitor, RMC-6236, is currently under clinical evaluation in patients with KRAS-mutant solid tumours (ClinicalTrials.gov identifier: NCT05379985).

The cumulative incidence and risk factors associated with 5-year conversion to knee arthroplasty following primary meniscus repair or primary meniscectomy.

Background: This study aimed to observe the 5-year knee arthroplasty conversion incidence rate and associated risk factors in patients who underwent meniscus procedures. Methods: Using a national database, we analyzed patients who had undergone primary meniscus repair or meniscectomy without prior knee surgeries. The cumulative knee arthroplasty conversion incidence was determined via Kaplan Meier analysis. Risk factors for conversion within 5 years were assessed using a Cox proportional hazard ratio model, with results as hazard ratios (HR). Results: 8125 patients had meniscus repair, while 240,209 had meniscectomy. 5-year conversion rates: repair 1.7%, meniscectomy 8.4%. Arthroplasty likelihood decreased as age decreased for repair (70+ [HR: 162.20]; 60-69 [HR: 81.64]; 50-59 [HR: 49.85]; 40-49 [HR: 17.79]; p < 0.001 all). Additional risk factors included male sex (HR: 0.35; p < 0.001) and higher Charlson Comorbidity Index (CCI) (CCI1 [HR: 1.28; p = 0.012]). For meniscectomy, arthroplasty likelihood also decreased with age (70+ [HR: 99.41]; 60-69 [HR: 84.57]; 50-59 [HR: 66.60]; 40-49 [HR: 36.15]; 30-39 [HR: 10.18]; p < 0.001 all). Additional risk factors included male sex (HR: 0.68; p < 0.001), obesity (HR: 1.18; p < 0.001), smoking (HR: 0.1.12; p = 0.010), and higher CCI (CCI1 [HR: 1.25]; CCI2 [HR 1.39]; CCI3+ [HR 1.46]; p < 0.001 all). Conclusion: This study revealed the national 5-year conversion incidence following primary meniscus repair (1.7%) and meniscectomy (8.4%). It also enhanced understanding of age, sex, obesity, smoking, comorbidities (CCI), and knee arthroplasty likelihood after meniscus procedures.

Multi-modal profiling of human fetal liver hematopoietic stem cells reveals the molecular signature of engraftment.

The human hematopoietic stem cell harbors remarkable regenerative potential that can be harnessed therapeutically. During early development, hematopoietic stem cells in the fetal liver undergo active expansion while simultaneously retaining robust engraftment capacity, yet the underlying molecular program responsible for their efficient engraftment remains unclear. Here, we profile 26,407 fetal liver cells at both the transcriptional and protein level including ~7,000 highly enriched and functional fetal liver hematopoietic stem cells to establish a detailed molecular signature of engraftment potential. Integration of transcript and linked cell surface marker expression reveals a generalizable signature defining functional fetal liver hematopoietic stem cells and allows for the stratification of enrichment strategies with high translational potential. More precisely, our integrated analysis identifies CD201 (endothelial protein C receptor (EPCR), encoded by PROCR) as a marker that can specifically enrich for engraftment potential. This comprehensive, multi-modal profiling of engraftment capacity connects a critical biological function at a key developmental timepoint with its underlying molecular drivers. As such, it serves as a useful resource for the field and forms the basis for further biological exploration of strategies to retain the engraftment potential of hematopoietic stem cells ex vivo or induce this potential during in vitro hematopoietic stem cell generation.

Two cadmium coordination polymers with bridging acetate and phenyl-enedi-amine ligands that exhibit two-dimensional layered structures.

Poly[tetra-µ2-acetato-κ8O:O'-bis-(µ2-benzene-1,2-di-amine-κ2N:N')dicadmium], [Cd2(CH3COO)4(C6H8N2)2] n , (I), and poly[[(µ2-acetato-κ2O:O')(acetato-κ2O,O')(µ2-benzene-1,3-di-amine-κ2N:N')cadmium] hemihydrate], {[Cd(CH3COO)2(C6H8N2)]·0.5H2O} n , (II), have two-dimensional polymeric structures in which monomeric units are joined by bridging acetate and benzenedi-amine ligands. Each of the CdII ions has an O4N2 coordination environment. The coordination geometries of the symmetry-independent CdII ions are distorted octa-hedral and distorted trigonal anti-prismatic in (I) and distorted anti-prismatic in (II). Both compounds exhibit an intra-layer hydrogen-bonding network. In addition, the water of hydration in (II) is involved in inter-layer hydrogen bonding.

Poly[[tris-(µ2-acetato-κ(2) O:O')(4-chloro-benzene-1,2-di-amine-κN)(µ3-hydroxido)dizinc] ethanol monosolvate].

The title compound, {[Zn2(CH3CO2)3(OH)(C6H7ClN2)]·C2H5OH} n , has alternating octa-hedrally and tetra-hedrally coordinated Zn(2+) ions. The octa-hedral coordination sphere is composed of one N atom of the monodentate di-amino-chloro-benzene ligand, three acetate O atoms and two bridging hydroxide ligands. The tetra-hedral coordination sphere consists of three acetate O atoms and the hydroxide ligand. The zinc ions are bridged by acetate and hydroxide ligands. The result is a laddered-chain structure parallel to [100] with ethanol solvent mol-ecules occupying the space between the chains. The di-amine ligand chlorine substitutent is disordered over two equally populated positions as a result of a crystallographically imposed inversion center between adjacent ligands. The ethanol solvent mol-ecule exhibits disorder with the two components having refined occupancies of 0.696 (11) and 0.304 (11). O-H⋯O hydrogen bonds form between the hydroxide ligand and the ethanol solvent mol-ecule. N-H⋯O and N-H⋯N hydrogen bonding between the uncoordinated amine group and the acetate ligands and the coordinated amine group are also observed.

Crystal structures of three lead(II) acetate-bridged di-amino-benzene coordination polymers.

Poly[tris-(acetato-κ(2) O,O')(µ2-acetato-κ(3) O,O':O)tetra-kis-(µ3-acetato-κ(4) O,O':O:O')bis-(benzene-1,2-di-amine-κN)tetra-lead(II)], [Pb4(CH3COO)8(C6H8N2)2] n , (I), poly[(acetato-κ(2) O,O')(µ3-acetato-κ(4) O,O':O:O')(4-chloro-benzene-1,2-diamine-κN)lead(II)], [Pb(CH3COO)2(C6H7ClN2)] n , (II), and poly[(κ(2) O,O')(µ3-acetato-κ(4) O,O':O:O')(3,4-di-amino-benzo-nitrile-κN)lead(II)], [Pb(CH3COO)2(C7H7N3)] n , (III), have polymeric structures in which monomeric units are joined by bridging acetate ligands. All of the Pb(II) ions exhibit hemidirected coordination. The repeating unit in (I) is composed of four Pb(II) ions having O6, O6N, O7 and O6N coordination spheres, respectively, where N represents a monodentate benzene-1,2-di-amine ligand and O acetate O atoms. Chains along [010] are joined by bridging acetate ligands to form planes parallel to (10-1). (II) and (III) are isotypic and have one Pb(II) ion in the asymmetric unit that has an O6N coordination sphere. Pb2O2 units result from a symmetry-imposed inversion center. Polymeric chains parallel to [100] exhibit hydrogen bonding between the amine and acetate ligands. In (III), additional hydrogen bonds between cyano groups and non-coordinating amines join the chains by forming R 2 (2)(14) rings.