RESUMEN
Pancreatic ductal adenocarcinoma (PDAC) has limited treatment options, emphasizing the urgent need for effective therapies. The predominant driver in PDAC is mutated KRAS proto-oncogene, KRA, present in 90% of patients. The emergence of direct KRAS inhibitors presents a promising avenue for treatment, particularly those targeting the KRASG12C mutated allele, which show encouraging results in clinical trials. However, the development of resistance necessitates exploring potent combination therapies. Our objective was to identify effective KRASG12C-inhibitor combination therapies through unbiased drug screening. Results revealed synergistic effects with son of sevenless homolog 1 (SOS1) inhibitors, tyrosine-protein phosphatase non-receptor type 11 (PTPN11)/Src homology region 2 domain-containing phosphatase-2 (SHP2) inhibitors, and broad-spectrum multi-kinase inhibitors. Validation in a novel and unique KRASG12C-mutated patient-derived organoid model confirmed the described hits from the screening experiment. Our findings propose strategies to enhance KRASG12C-inhibitor efficacy, guiding clinical trial design and molecular tumor boards.
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BACKGROUND: Salt Overly Sensitive 1 (SOS1), a plasma membrane Na+/H+ exchanger, is essential for plant salt tolerance. Salt damage is a significant abiotic stress that impacts plant species globally. All living organisms require copper (Cu), a necessary micronutrient and a protein cofactor for many biological and physiological processes. High Cu concentrations, however, may result in pollution that inhibits the growth and development of plants. The function and production of mangrove ecosystems are significantly impacted by rising salinity and copper contamination. RESULTS: A genome-wide analysis and bioinformatics techniques were used in this study to identify 20 SOS1 genes in the genome of Kandelia obovata. Most of the SOS1 genes were found on the plasma membrane and dispersed over 11 of the 18 chromosomes. Based on phylogenetic analysis, KoSOS1s can be categorized into four groups, similar to Solanum tuberosum. Kandelia obovata's SOS1 gene family expanded due to tandem and segmental duplication. These SOS1 homologs shared similar protein structures, according to the results of the conserved motif analysis. The coding regions of 20 KoSOS1 genes consist of amino acids ranging from 466 to 1221, while the exons include amino acids ranging from 3 to 23. In addition, we found that the 2.0 kb upstream promoter region of the KoSOS1s gene contains several cis-elements associated with phytohormones and stress responses. According to the expression experiments, seven randomly chosen genes experienced up- and down-regulation of their expression levels in response to copper (CuCl2) and salt stressors. CONCLUSIONS: For the first time, this work systematically identified SOS1 genes in Kandelia obovata. Our investigations also encompassed physicochemical properties, evolution, and expression patterns, thereby furnishing a theoretical framework for subsequent research endeavours aimed at functionally characterizing the Kandelia obovata SOS1 genes throughout the life cycle of plants.
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Cobre , Filogenia , Proteínas de Plantas , Rhizophoraceae , Cobre/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Rhizophoraceae/genética , Rhizophoraceae/fisiología , Estrés Salino/genética , Regulación de la Expresión Génica de las Plantas , Genoma de Planta , Familia de Multigenes , Estrés Fisiológico/genética , Genes de Plantas , Tolerancia a la Sal/genética , Proteína SOS1/genética , Proteína SOS1/metabolismoRESUMEN
A key prerequisite for the successful application of protein crystallography in drug discovery is to establish a robust crystallization system for a new drug-target protein fast enough to deliver crystal structures when the first inhibitors have been identified in the hit-finding campaign or, at the latest, in the subsequent hit-to-lead process. The first crucial step towards generating well folded proteins with a high likelihood of crystallizing is the identification of suitable truncation variants of the target protein. In some cases an optimal length variant alone is not sufficient to support crystallization and additional surface mutations need to be introduced to obtain suitable crystals. In this contribution, four case studies are presented in which rationally designed surface modifications were key to establishing crystallization conditions for the target proteins (the protein kinases Aurora-C, IRAK4 and BUB1, and the KRAS-SOS1 complex). The design process which led to well diffracting crystals is described and the crystal packing is analysed to understand retrospectively how the specific surface mutations promoted successful crystallization. The presented design approaches are routinely used in our team to support the establishment of robust crystallization systems which enable structure-guided inhibitor optimization for hit-to-lead and lead-optimization projects in pharmaceutical research.
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Cristalización , Cristalización/métodos , Cristalografía por Rayos X/métodos , Humanos , Descubrimiento de Drogas/métodos , Mutación , Modelos Moleculares , Proteínas Serina-Treonina Quinasas/químicaRESUMEN
The Kirsten rat sarcoma virus-son of sevenless 1 (KRAS-SOS1) axis drives tumor growth preferentially in pancreatic, colon, and lung cancer. Now, KRAS G12C mutated tumors can be successfully treated with inhibitors that covalently block the cysteine of the switch II binding pocket of KRAS. However, the range of other KRAS mutations is not amenable to treatment and the G12C-directed agents Sotorasib and Adragrasib show a response rate of only approximately 40%, lasting for a mean period of 8 months. One approach to increase the efficacy of inhibitors is their inclusion into proteolysis-targeting chimeras (PROTACs), which degrade the proteins of interest and exhibit much higher antitumor activity through multiple cycles of activity. Accordingly, PROTACs have been developed based on KRAS- or SOS1-directed inhibitors coupled to either von Hippel-Lindau (VHL) or Cereblon (CRBN) ligands that invoke the proteasomal degradation. Several of these PROTACs show increased activity in vitro and in vivo compared to their cognate inhibitors but their toxicity in normal tissues is not clear. The CRBN PROTACs containing thalidomide derivatives cannot be tested in experimental animals. Resistance to such PROTACS arises through downregulation or inactivation of CRBN or factors of the functional VHL E3 ubiquitin ligase. Although highly active KRAS and SOS1 PROTACs have been formulated their clinical application remains difficult.
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Proteolisis , Proteínas Proto-Oncogénicas p21(ras) , Proteína SOS1 , Humanos , Proteína SOS1/metabolismo , Proteína SOS1/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Animales , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Neoplasias/genética , Neoplasias/patología , Antineoplásicos/farmacología , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Quimera Dirigida a la ProteólisisRESUMEN
Lesions of the semilunar valve and the aortic arch can occur either in isolation or as part of well-described clinical syndromes. The polygenic cause of calcific aortic valve disease will be discussed including the key role of NOTCH1 mutations. In addition, the complex trait of bicuspid aortic valve disease will be outlined, both in sporadic/familial cases and in the context of associated syndromes, such as Alagille, Williams, and Kabuki syndromes. Aortic arch abnormalities particularly coarctation of the aorta and interrupted aortic arch, including their association with syndromes such as Turner and 22q11 deletion, respectively, are also discussed. Finally, the genetic basis of congenital pulmonary valve stenosis is summarized, with particular note to Ras-/mitogen-activated protein kinase (Ras/MAPK) pathway syndromes and other less common associations, such as Holt-Oram syndrome.
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Aorta Torácica , Válvula Aórtica , Humanos , Aorta Torácica/anomalías , Aorta Torácica/patología , Válvula Aórtica/anomalías , Válvula Aórtica/patología , Anomalías Múltiples/genética , Anomalías Múltiples/patología , Cardiopatías Congénitas/genética , Cardiopatías Congénitas/patología , Enfermedad de la Válvula Aórtica Bicúspide/genética , Estenosis de la Válvula Pulmonar/genética , Mutación , Receptor Notch1/genética , Enfermedad de la Válvula Aórtica/genética , Enfermedades de las Válvulas Cardíacas/genética , Enfermedades de las Válvulas Cardíacas/patología , Calcinosis/genética , Calcinosis/patología , Enfermedades Hematológicas/genética , Enfermedades Hematológicas/patología , Enfermedades Vestibulares/genética , Enfermedades Vestibulares/patologíaRESUMEN
Preclinical studies rarely test the efficacy of therapies in both sexes. The field of oncology is no exception in this regard. In a model of syngeneic, orthotopic, metastasized pancreatic ductal adenocarcinoma we evaluated the impact of sex on pathological features of this disease as well as on the efficacy and possible adverse side effects of a novel, small molecule-based therapy inhibiting KRAS:SOS1, MEK1/2 and PI3K signaling in male and female C57BL/6J mice. Male mice had less tumor infiltration of CD8-positive cells, developed bigger tumors, had more lung metastasis and a lower probability of survival compared to female mice. These more severe pathological features in male animals were accompanied by higher distress at the end of the experiment. The evaluated inhibitors BI-3406, trametinib and BKM120 showed synergistic effects in vitro. This combinatorial therapy reduced tumor weight more efficiently in male animals, although the drug concentrations were similar in the tumors of both sexes. These results underline the importance of sex-specific preclinical research and at the same time provide a solid basis for future studies with the tested compounds.
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Polyphyllin VII is a biologically active herbal monomer extracted from the traditional Chinese herbal medicine Chonglou. Many studies have demonstrated the anticancer activity of polyphyllin VII against various types of cancers, such as colon, liver, and lung cancer, but its effect on breast cancer has not been elucidated. In this study, we demonstrate that polyphyllin VII inhibited proliferation, increased production of intracellular reactive oxygen species, and decreased mitochondrial membrane potential in breast cancer cells. Notably, polyphyllin VII also induced apoptosis via the mitochondrial pathway. Transcriptome sequencing was used to analyze the targets of PPVII in regulating breast cancer cells. Mechanistic studies showed that polyphyllin VII downregulated Son of Sevenless1 (SOS1) and inhibited the MAPK/ERK pathway. Furthermore, PPVII exerted strong antitumor effects in vivo in nude mice injected with breast cancer cells. Our results suggest that PPVII may promote apoptosis through regulating the SOS1/MAPK/ERK pathway, making it a possible candidate target for the treatment of breast cancer.
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Apoptosis , Neoplasias de la Mama , Regulación hacia Abajo , Sistema de Señalización de MAP Quinasas , Proteína SOS1 , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Neoplasias de la Mama/genética , Animales , Humanos , Femenino , Regulación hacia Abajo/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Proteína SOS1/metabolismo , Proteína SOS1/genética , Ratones Desnudos , Saponinas/farmacología , Saponinas/uso terapéutico , Proliferación Celular/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Ratones , Línea Celular Tumoral , Medicamentos Herbarios Chinos/farmacología , Fitoterapia , Antineoplásicos Fitogénicos/farmacología , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones Endogámicos BALB CRESUMEN
Oncogenic KRAS mutations drive an approximately 25 % of all human cancers. Son of Sevenless 1 (SOS1), a critical guanine nucleotide exchange factor, catalyzes the activation of KRAS. Targeting SOS1 degradation has engaged as a promising therapeutic strategy for KRAS-mutant cancers. Herein, we designed and synthesized a series of novel CRBN-recruiting SOS1 PROTACs using the pyrido[2,3-d]pyrimidin-7-one-based SOS1 inhibitor as the warhead. One representative compound 11o effectively induced the degradation of SOS1 in three different KRAS-mutant cancer cell lines with DC50 values ranging from 1.85 to 7.53 nM. Mechanism studies demonstrated that 11o-induced SOS1 degradation was dependent on CRBN and proteasome. Moreover, 11o inhibited the phosphorylation of ERK and displayed potent anti-proliferative activities against SW620, A549 and DLD-1 cells. Further optimization of 11o may provide us promising SOS1 degraders with favorable drug-like properties for developing new chemotherapies targeting KRAS-driven cancers.
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Antineoplásicos , Proliferación Celular , Diseño de Fármacos , Proteína SOS1 , Humanos , Proteína SOS1/metabolismo , Proteína SOS1/antagonistas & inhibidores , Antineoplásicos/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Relación Estructura-Actividad , Línea Celular Tumoral , Estructura Molecular , Ensayos de Selección de Medicamentos Antitumorales , Relación Dosis-Respuesta a Droga , Pirimidinas/farmacología , Pirimidinas/síntesis química , Pirimidinas/química , Pirimidinonas/farmacología , Pirimidinonas/síntesis química , Pirimidinonas/química , Quimera Dirigida a la ProteólisisRESUMEN
BACKGROUND: CSLCs(Cancer stem cell-like cells), which are central to tumorigenesis, are intrinsically influenced by epigenetic modifications. This study aimed to elucidate the underlying mechanism involving the DNMT1/miR-152-3p/SOS1 axis in regulating the self-renewal and tumor growth of LCSLCs (lung cancer stem-like cells). MATERIALS AND METHODS: Target genes of miR-152-3p were predicted using TargetScan Human 8.0. Self-renewal and tumor growth of LCSLC were compared in suspension-cultured non-small cell lung cancer (NSCLC) cell lines H460 and A549 cell-derived globe cells. Functional effects of the DNMT1/miR-152-3p/SOS1 axis were assessed through gain-of-function experiments in vitro and in vivo. Additionally, luciferase reporter assays were employed to analyze the interaction among DNMT1, miR-152-3p, and SOS1. RESULTS: Our findings highlight a negative interaction between DNMT1 and miR-152-3p, resulting in reduced miR-152-3p level. This, in turn, leads to the alleviation of the inhibitory effect of miR-152-3p on the target gene SOS1, ultimately activating SOS1 and playing an essential role in self-renewal and tumor growth of LCSLC. However, the alteration of SOS1 does not affect DNMT1/miR-152-3p regulation. Therefore, it is reasonable to infer that the DNMT1/miR-152-3p negative feedback loop critically sustains self-renewal and tumor growth of LCSLC through SOS1. CONCLUSIONS: This study reveals a novel mechanism underpinning self-renewal and tumor growth of CSLC (cancer stem cell) in NSCLC and identifies potential therapeutic targets for NSCLC treatment.
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Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , MicroARNs , Humanos , Carcinoma de Pulmón de Células no Pequeñas/patología , Movimiento Celular , Proliferación Celular , Metilación de ADN , Regulación Neoplásica de la Expresión Génica , Neoplasias Pulmonares/patología , MicroARNs/genética , MicroARNs/metabolismo , Células Madre Neoplásicas/metabolismo , Línea Celular TumoralRESUMEN
The RAS-MAPK signaling pathway, crucial for cell proliferation and differentiation, involves key proteins KRAS and SOS1. Mutations in the KRAS and SOS1 genes are implicated in various cancer types, including pancreatic, lung, and juvenile myelomonocytic leukemia. There is considerable interest in identifying inhibitors targeting KRAS and SOS1 to explore potential therapeutic strategies for cancer treatment. In this study, advanced in silico techniques were employed to screen small molecule libraries at this interface, leading to the identification of promising lead compounds as potential SOS1 inhibitors. Comparative analysis of the average binding free energies of these predicted potent compounds with known SOS1 small molecule inhibitors revealed that the identified compounds display similar or even superior predicted binding affinities compared to the known inhibitors. These findings offer valuable insights into the potential of these compounds as candidates for further development as effective anti-cancer agents.
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Proteínas Proto-Oncogénicas p21(ras) , Proteína SOS1 , Bibliotecas de Moléculas Pequeñas , Proteína SOS1/metabolismo , Proteína SOS1/antagonistas & inhibidores , Proteína SOS1/química , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/farmacología , Humanos , Proteínas Proto-Oncogénicas p21(ras)/antagonistas & inhibidores , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/genética , Antineoplásicos/farmacología , Antineoplásicos/química , Simulación del Acoplamiento Molecular , Unión Proteica , Evaluación Preclínica de MedicamentosRESUMEN
Pancreatic cancer has a dismal prognosis due to late detection and lack of efficient therapies. The Kirsten rat sarcoma virus (KRAS) oncogene is mutated in up to 90% of all pancreatic ductal adenocarcinomas (PDACs) and constitutes an attractive target for therapy. However, the most common KRAS mutations in PDAC are G12D (44%), G12V (34%) and G12R (20%) that are not amenable to treatment by KRAS G12C-directed cysteine-reactive KRAS inhibitors such as Sotorasib and Adagrasib that exhibit clinical efficacy in lung cancer. KRAS G12C mutant pancreatic cancer has been treated with Sotorasib but this mutation is detected only in 2%-3% of PDAC. Recently, the KRAS G12D-directed MRTX1133 inhibitor has entered clinical trials and more of such inhibitors are in development. The other KRAS mutations may be targeted indirectly via inhibition of the cognate guanosine exchange factor (GEF) Son of Sevenless 1 that drives KRAS. These agents seem to provide the means to target the most frequent KRAS mutations in PDAC and to improve patient outcomes.
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Terapia Molecular Dirigida , Mutación , Neoplasias Pancreáticas , Proteínas Proto-Oncogénicas p21(ras) , Humanos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/genética , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/tratamiento farmacológico , Carcinoma Ductal Pancreático/patología , Carcinoma Ductal Pancreático/metabolismo , Antineoplásicos/uso terapéutico , Antineoplásicos/farmacología , AnimalesRESUMEN
Son of sevenless homolog 1 (SOS1) plays a pivotal role as a molecular switch in the conversion of GDP-bound inactive KRAS to its active GTP-bound form, making SOS1 a promising therapeutic target for KRAS-driven cancers. While the most advanced SOS1 inhibitor has processed to phase I clinical trial, the exploration of novel SOS1 targeting strategies with distinct modes of action remains required. By employing proteolysis targeting chimera (PROTAC) technology, we obtained a series of new SOS1 degraders. The representative compound LHF418 potently induced SOS1 degradation with a DC50 value of 209.4 nM and a Dmax value of over 80 %. Mechanistic studies have illuminated that compound LHF418 induced the formation of ternary complex involving SOS1-PROTAC-cereblon (CRBN) and triggered SOS1 protein degradation in a CRBN- and proteasome-dependent manner. In addition, compound LHF418 effectively inhibited KRAS-RAF-ERK signalling, leading to the suppression of colony formation in KRAS-driven cancer cells. Overall, compound LHF418 represents a new lead compound in the developing novel and potent therapy for the treatment of KRAS-driven cancers.
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Quimera Dirigida a la Proteólisis , Proteínas Proto-Oncogénicas p21(ras) , Línea Celular Tumoral , Proteolisis , Proteínas Proto-Oncogénicas p21(ras)/genética , Transducción de SeñalRESUMEN
The Son of Sevenless 1 (SOS1) guanine nucleotide exchange factor, prevalent across eukaryotic species, plays a pivotal role in facilitating the attachment of RAS protein to GTP, thereby regulating the activation of intracellular RAS proteins. This regulation is part of a feedback mechanism involving SOS1, which allows both activators and inhibitors of SOS1 to exert control over downstream signaling pathways, demonstrating potential anti-tumor effects. Predominantly, small molecule modulators that target SOS1 focus on a hydrophobic pocket within the CDC25 protein domain. The effectiveness of these modulators largely depends on their ability to interact with specific amino acids, notably Phe890 and Tyr884. This interaction is crucial for influencing the protein-protein interaction (PPI) between RAS and the catalytic domain of SOS1. Currently, most small molecule modulators targeting SOS1 are in the preclinical research phase, with a few advancing to clinical trials. This progression raises safety concerns, making the assurance of drug safety a primary consideration alongside the enhancement of efficacy in the development of SOS1 modulators. This review encapsulates recent advancements in the chemical categorization of SOS1 inhibitors and activators. It delves into the evolution of small molecule modulation targeting SOS1 and offers perspectives on the design of future generations of selective SOS1 small molecule modulators.
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Núcleo Familiar , Transducción de Señal , Descubrimiento de Drogas , Dominio CatalíticoRESUMEN
The plasmalemma Na+/H+ antiporter Salt Overly Sensitive 1 (SOS1) is responsible for the efflux of Na+ from the cytoplasm, an important determinant of salt resistance in plants. In this study, an ortholog of SOS1, referred to as NsSOS1, was cloned from Nitraria sibirica, a typical halophyte that grows in deserts and saline-alkaline land, and its expression and function in regulating the salt tolerance of forest trees were evaluated. The expression level of NsSOS1 was higher in leaves than in roots and stems of N. sibirica, and its expression was upregulated under salt stress. Histochemical staining showed that ß-glucuronidase (GUS) driven by the NsSOS1 promoter was strongly induced by abiotic stresses and phytohormones including salt, drought, low temperature, gibberellin, and methyl jasmonate, suggesting that NsSOS1 is involved in the regulation of multiple signaling pathways. Transgenic 84â¯K poplar (Populus alba × P. glandulosa) overexpressing NsSOS1 showed improvements in survival rate, root biomass, plant height, relative water levels, chlorophyll and proline levels, and antioxidant enzyme activities versus non-transgenic poplar (NT) under salt stress. Transgenic poplars accumulated less Na+ and more K+ in roots, stems, and leaves, which had a lower Na+/K+ ratio compared to NT under salt stress. These results indicate that NsSOS1-mediated Na+ efflux confers salt tolerance to transgenic poplars, which show more efficient photosynthesis, better scavenging of reactive oxygen species, and improved osmotic adjustment under salt stress. Transcriptome analysis of transgenic poplars confirmed that NsSOS1 not only mediates Na+ efflux but is also involved in the regulation of multiple metabolic pathways. The results provide insight into the regulatory mechanisms of NsSOS1 and suggest that it could be used to improve the salt tolerance of forest trees.
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Populus , Plantas Tolerantes a la Sal , Plantas Tolerantes a la Sal/genética , Plantas Tolerantes a la Sal/metabolismo , Tolerancia a la Sal/genética , Plantas Modificadas Genéticamente/metabolismo , Antiportadores/metabolismo , Populus/metabolismo , Estrés Fisiológico , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMEN
KRAS activation is known to be modulated by a guanine nucleotide exchange factor (GEF), namely, Son of Sevenless1 (SOS1). SOS1 facilitates the exchange of GDP to GTP thereby leading to activation of KRAS. The binding of GDP/GTP to KRAS at the REM/allosteric site of SOS1 regulates the activation of KRAS at CDC25/catalytic site by facilitating its exchange. Different aspects of the allosteric activation of KRAS through SOS1 are still being explored. To understand the SOS1 mediated activation of KRAS, molecular dynamics simulations for a total of nine SOS1 complexes (KRAS-SOS1-KRAS) were performed. These nine systems comprised different combinations of KRAS-bound nucleotides (GTP/GDP) at REM and CDC25 sites of SOS1. Various conformational and thermodynamic parameters were analyzed for these simulation systems. MMPBSA free energy analysis revealed that binding at CDC25 site of SOS1 was significantly low for GDP-bound KRAS as compared to that of GTP-bound KRAS. It was observed that presence of either GDP/GTP bound KRAS at the REM site of SOS1 affected the activation related changes in the KRAS present at CDC25 site. The conformational changes at the catalytic site of SOS1 resulting from GDP/GTP-bound KRAS at the allosteric changes may hint at KRAS activation through different pathways (slow/fast/rare). The allosteric effect on activation of KRAS at CDC25 site may be due to conformations adopted by switch-I, switch-II, beta2 regions of KRAS at REM site. The effect of structural rearrangements occurring at allosteric KRAS may have led to increased interactions between SOS1 and KRAS at both the sites. The SOS1 residues involved in these important interactions with KRAS at the REM site were R694, S732 and K735. Whereas the ones interacting with KRAS at CDC25 site were S807, W809 and K814. This may suggest the crucial role of these residues in guiding the allosteric activation of KRAS at CDC25 site. The conformational shifts observed in the switch-I, switch-II and alpha3 regions of KRAS at CDC25 site may be attributed to be a part of allosteric activation. The binding affinities, interacting residues and conformational dynamics may provide an insight into development of inhibitors targeting the SOS1 mediated KRAS activation.
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SRC homology 3 (SH3) domains are critical interaction modules that orchestrate the assembly of protein complexes involved in diverse biological processes. They facilitate transient protein-protein interactions by selectively interacting with proline-rich motifs (PRMs). A database search revealed 298 SH3 domains in 221 human proteins. Multiple sequence alignment of human SH3 domains is useful for phylogenetic analysis and determination of their selectivity towards PRM-containing peptides (PRPs). However, a more precise functional classification of SH3 domains is achieved by constructing a phylogenetic tree only from PRM-binding residues and using existing SH3 domain-PRP structures and biochemical data to determine the specificity within each of the 10 families for particular PRPs. In addition, the C-terminal proline-rich domain of the RAS activator SOS1 covers 13 of the 14 recognized proline-rich consensus sequence motifs, encompassing differential PRP pattern selectivity among all SH3 families. To evaluate the binding capabilities and affinities, we conducted fluorescence dot blot and polarization experiments using 25 representative SH3 domains and various PRPs derived from SOS1. Our analysis has identified 45 interacting pairs, with binding affinities ranging from 0.2 to 125 micromolar, out of 300 tested and potential new SH3 domain-SOS1 interactions. Furthermore, it establishes a framework to bridge the gap between SH3 and PRP interactions and provides predictive insights into the potential interactions of SH3 domains with PRMs based on sequence specifications. This novel framework has the potential to enhance the understanding of protein networks mediated by SH3 domain-PRM interactions and be utilized as a general approach for other domain-peptide interactions.
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Péptidos , Dominios Homologos src , Humanos , Secuencia de Aminoácidos , Proteína Adaptadora GRB2/metabolismo , Unión Proteica , Filogenia , Péptidos/metabolismo , Prolina/metabolismoRESUMEN
Kirsten rat sarcoma 2 viral oncogene homolog (KRAS) is the most frequently mutated oncogene in human cancers with mutations predominantly occurring in codon 12. These mutations disrupt the normal function of KRAS by interfering with GTP hydrolysis and nucleotide exchange activity, making it prone to the GTP-bound active state, thus leading to sustained activation of downstream pathways. Despite decades of research, there has been no progress in the KRAS drug discovery until the groundbreaking discovery of covalently targeting the KRASG12C mutation in 2013, which led to revolutionary changes in KRAS-targeted therapy. So far, two small molecule inhibitors sotorasib and adagrasib targeting KRASG12C have received accelerated approval for the treatment of non-small cell lung cancer (NSCLC) harboring KRASG12C mutations. In recent years, rapid progress has been achieved in the KRAS-targeted therapy field, especially the exploration of KRASG12C covalent inhibitors in other KRASG12C-positive malignancies, novel KRAS inhibitors beyond KRASG12C mutation or pan-KRAS inhibitors, and approaches to indirectly targeting KRAS. In this review, we provide a comprehensive overview of the molecular and mutational characteristics of KRAS and summarize the development and current status of covalent inhibitors targeting the KRASG12C mutation. We also discuss emerging promising KRAS-targeted therapeutic strategies, with a focus on mutation-specific and direct pan-KRAS inhibitors and indirect KRAS inhibitors through targeting the RAS activation-associated proteins Src homology-2 domain-containing phosphatase 2 (SHP2) and son of sevenless homolog 1 (SOS1), and shed light on current challenges and opportunities for drug discovery in this field.
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Antineoplásicos , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Terapia Molecular Dirigida , Proteínas Proto-Oncogénicas p21(ras) , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Descubrimiento de Drogas , Guanosina Trifosfato , Neoplasias Pulmonares/tratamiento farmacológico , Mutación , Proteínas Proto-Oncogénicas p21(ras)/antagonistas & inhibidores , Proteínas Proto-Oncogénicas p21(ras)/genética , Antineoplásicos/química , Antineoplásicos/uso terapéuticoRESUMEN
K-Ras is a frequently mutated oncogene in human malignancies, and the development of inhibitors targeting various oncogenic K-Ras mutant proteins is a major challenge in targeted cancer therapy, especially K-Ras(G12C) is the most common mutant, which occurs in pancreatic ductal adenocarcinoma (PDAC), non-small cell lung cancer (NSCLC), colorectal cancer (CRC) and other highly prevalent malignancies. In recent years, significant progress has been made in developing small molecule covalent inhibitors targeting K-Ras(G12C), thanks to the production of nucleophilic cysteine by the G12C mutant, breaking the "spell" that K-Ras protein cannot be used as a drug target. With the successful launch of sotorasib and adagrasib, the development of small molecule inhibitors targeting various K-Ras mutants has continued to gain momentum. In recent years, with the popularization of highly sensitive surface plasmon resonance (SPR) technology, fragment-based drug design strategies have shown great potential in the development of small molecule inhibitors targeting K-Ras(G12C), but with the increasing number of clinically reported acquired drug resistance, addressing inhibitor resistance has gradually become the focus of this field, indirectly indicating that such small molecule inhibitors still the potential for the development of these small molecule inhibitors are also indirectly indicated. This paper traces the development of small molecule covalent inhibitors targeting K-Ras(G12C), highlighting and analyzing the structural evolution and optimization process of each series of inhibitors and the previous inhibitor design methods and strategies, as well as their common problems and general solutions, in order to provide inspiration and help to the subsequent researchers.
RESUMEN
KRAS is the most commonly mutated oncogene. Targeted therapies have been developed against mediators of key downstream signaling pathways, predominantly components of the RAF/MEK/ERK kinase cascade. Unfortunately, single-agent efficacy of these agents is limited both by intrinsic and acquired resistance. Survival of drug-tolerant persister cells within the heterogeneous tumor population and/or acquired mutations that reactivate receptor tyrosine kinase (RTK)/RAS signaling can lead to outgrowth of tumor-initiating cells (TICs) and drive therapeutic resistance. Here, we show that targeting the key RTK/RAS pathway signaling intermediates SOS1 (Son of Sevenless 1) or KSR1 (Kinase Suppressor of RAS 1) both enhances the efficacy of, and prevents resistance to, the MEK inhibitor trametinib in KRAS-mutated lung (LUAD) and colorectal (COAD) adenocarcinoma cell lines depending on the specific mutational landscape. The SOS1 inhibitor BI-3406 enhanced the efficacy of trametinib and prevented trametinib resistance by targeting spheroid-initiating cells in KRASG12/G13-mutated LUAD and COAD cell lines that lacked PIK3CA comutations. Cell lines with KRASQ61 and/or PIK3CA mutations were insensitive to trametinib and BI-3406 combination therapy. In contrast, deletion of the RAF/MEK/ERK scaffold protein KSR1 prevented drug-induced SIC upregulation and restored trametinib sensitivity across all tested KRAS mutant cell lines in both PIK3CA-mutated and PIK3CA wild-type cancers. Our findings demonstrate that vertical inhibition of RTK/RAS signaling is an effective strategy to prevent therapeutic resistance in KRAS-mutated cancers, but therapeutic efficacy is dependent on both the specific KRAS mutant and underlying comutations. Thus, selection of optimal therapeutic combinations in KRAS-mutated cancers will require a detailed understanding of functional dependencies imposed by allele-specific KRAS mutations.
Asunto(s)
Neoplasias Colorrectales , Fosfatidilinositol 3-Quinasas , Humanos , Línea Celular Tumoral , Fosfatidilinositol 3-Quinasa Clase I/genética , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Quinasas Quinasa Quinasa PAM/metabolismo , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Mutación , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismoRESUMEN
Kristen rat sarcoma (KRAS) is one of the most common oncogenes in human cancers. As a guanine nucleotide exchange factor, Son of Sevenless Homologue 1 (SOS1) represents a potential therapeutic concept for the treatment of KRAS-mutant cancers because of its activation on KRAS and downstream signaling pathways. In this review, we provide a comprehensive overview of the structure, biological function, and regulation of SOS1. We also focus on the recent advances in SOS1 inhibitors and emphasize their binding modes, structure-activity relationships and pharmacological activities. We hope that this publication can provide a comprehensive compendium on the rational design of SOS1 inhibitors.