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1.
Proc Natl Acad Sci U S A ; 120(1): e2211297120, 2023 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-36574664

RESUMEN

WD repeat domain 5 (WDR5) is a core scaffolding component of many multiprotein complexes that perform a variety of critical chromatin-centric processes in the nucleus. WDR5 is a component of the mixed lineage leukemia MLL/SET complex and localizes MYC to chromatin at tumor-critical target genes. As a part of these complexes, WDR5 plays a role in sustaining oncogenesis in a variety of human cancers that are often associated with poor prognoses. Thus, WDR5 has been recognized as an attractive therapeutic target for treating both solid and hematological tumors. Previously, small-molecule inhibitors of the WDR5-interaction (WIN) site and WDR5 degraders have demonstrated robust in vitro cellular efficacy in cancer cell lines and established the therapeutic potential of WDR5. However, these agents have not demonstrated significant in vivo efficacy at pharmacologically relevant doses by oral administration in animal disease models. We have discovered WDR5 WIN-site inhibitors that feature bicyclic heteroaryl P7 units through structure-based design and address the limitations of our previous series of small-molecule inhibitors. Importantly, our lead compounds exhibit enhanced on-target potency, excellent oral pharmacokinetic (PK) profiles, and potent dose-dependent in vivo efficacy in a mouse MV4:11 subcutaneous xenograft model by oral dosing. Furthermore, these in vivo probes show excellent tolerability under a repeated high-dose regimen in rodents to demonstrate the safety of the WDR5 WIN-site inhibition mechanism. Collectively, our results provide strong support for WDR5 WIN-site inhibitors to be utilized as potential anticancer therapeutics.


Asunto(s)
Péptidos y Proteínas de Señalización Intracelular , Neoplasias , Repeticiones WD40 , Animales , Humanos , Ratones , Cromatina , Péptidos y Proteínas de Señalización Intracelular/antagonistas & inhibidores , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Modelos Animales , Neoplasias/tratamiento farmacológico , Línea Celular Tumoral
2.
BMC Cancer ; 23(1): 468, 2023 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-37217880

RESUMEN

BACKGROUND: Breast cancer brain metastasis (BCBM) is a growing therapeutic challenge and clinical concern. Stromal cancer-associated fibroblasts (CAFs) are crucial factors in the modulation of tumorigeneses and metastases. Herein, we investigated the relationship between the expression of stromal CAF markers in metastatic sites, platelet-derived growth factor receptor-beta (PDGFR-ß), and alpha-smooth muscle actin (α-SMA) and the clinical and prognostic variables in BCBM patients. METHODS: Immunohistochemistry (IHC) of the stromal expression of PDGFR-ß and α-SMA was performed on 50 cases of surgically resected BCBM. The expression of the CAF markers was analyzed in the context of clinico-pathological characteristics. RESULTS: Expression of PDGFR-ß and α-SMA was lower in the triple-negative (TN) subtype than in other molecular subtypes (p = 0.073 and p = 0.016, respectively). And their expressions were related to a specific pattern of CAF distribution (PDGFR-ß, p = 0.009; α-SMA, p = 0.043) and BM solidity (p = 0.009 and p = 0.002, respectively). High PDGFR-ß expression was significantly related to longer recurrence-free survival (RFS) (p = 0.011). TN molecular subtype and PDGFR-ß expression were independent prognostic factors of recurrence-free survival (p = 0.029 and p = 0.030, respectively) and TN molecular subtype was an independent prognostic factor of overall survival (p < 0.001). CONCLUSIONS: Expression of PDGFR-ß in the stroma of BM was associated with RFS in BCBM patients, and the clinical implication was uniquely linked to the low expression of PDGFR-ß and α-SMA in the aggressive form of the TN subtype.


Asunto(s)
Neoplasias Encefálicas , Neoplasias de la Mama , Femenino , Humanos , Actinas/metabolismo , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/patología , Relevancia Clínica , Fibroblastos/metabolismo , Pronóstico , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/genética , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Neoplasias Encefálicas/secundario
3.
Childs Nerv Syst ; 39(11): 3289-3294, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37354290

RESUMEN

Kaposiform hemangioendothelioma is an extremely rare vascular tumor which shows aggressive local growth. We present a case of rapid growing vascular skull tumor with dura invasion in a pediatric patient with neurofibromatosis type 1. A 14-year-old male complained of headache and dizziness for 1 month after minor head trauma. Brain magnetic resonance imaging (MRI) revealed a 5-cm-sized tumor in the left frontotemporal bone with internal hemorrhage and cystic changes. The gross total resection of tumor was done. At the 7-month follow-up, brain MRI revealed a recurrent skull tumor with intracranial dura mass. He underwent second surgery, and the pathologic diagnosis was suggestive of Kaposiform hemangioendothelioma. For this vascular proliferative tumor, mTOR inhibitor was treated for 6 months, and there was the recurred nodular-enhancing mass along the sphenoid ridge. After additional 2 months of medication, the following MRI revealed a decreased nodular-enhancing mass.


Asunto(s)
Síndrome de Kasabach-Merritt , Neoplasias Craneales , Neoplasias Vasculares , Adolescente , Humanos , Masculino , Síndrome de Kasabach-Merritt/diagnóstico por imagen , Síndrome de Kasabach-Merritt/cirugía , Recurrencia Local de Neoplasia , Base del Cráneo
4.
Acta Neurochir (Wien) ; 165(8): 2105-2109, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37421424

RESUMEN

Gamma knife radiosurgery (GKRS) has been accepted as a safe and effective treatment for vestibular schwannoma (VS). However, during follow-up, tumor expansion induced by irradiation can occur, and diagnosis of failure in radiosurgery for VS is still controversial. Tumor expansion with cystic enlargement causes some confusion regarding whether further treatment should be performed. We analyzed more than 10 years of clinical findings and imaging of patients with VS with cystic enlargement after GKRS. A 49-year-old male with hearing impairment was treated with GKRS (12 Gy; isodose, 50%) for a left VS with a preoperative tumor volume of 0.8 cc. The tumor size increased with cystic changes from the third year after GKRS, reaching a volume of 10.8 cc at 5 years after GKRS. At the 6th year of follow-up, the tumor volume started to decrease, up to 0.3 cc by the 14th year of follow-up. A 52-year-old female with hearing impairment and left facial numbness was treated with GKRS for a left VS (13 Gy; isodose, 50%). The preoperative tumor volume was 6.3 cc, which started to increase with cystic enlargement from the first year after GKRS, and reaching 18.2 cc by 5 years after GKRS. The tumor maintained a cystic pattern with slight changes in size, but no other neurologic symptoms developed during the follow-up period. After 6 years of GKRS, tumor regression was observed, eventually reaching a volume of 3.2 cc by the 13th year of follow-up. In both cases, persistent cystic enlargement in VS was observed at 5 years after GKRS, after which the tumors began to stabilize. After more than 10 years of GKRS, the tumor volume was less than that before GKRS. Enlargement with large cystic formation in the first 3-5 years after GKRS has been considered as treatment failure. However, our cases show that further treatment for cystic enlargement should be deferred for at least 10 years, especially in patients without neurological deterioration, as inadequate surgery can be prevented within that period.


Asunto(s)
Pérdida Auditiva , Neuroma Acústico , Radiocirugia , Masculino , Femenino , Humanos , Persona de Mediana Edad , Neuroma Acústico/diagnóstico por imagen , Neuroma Acústico/radioterapia , Neuroma Acústico/cirugía , Radiocirugia/efectos adversos , Radiocirugia/métodos , Resultado del Tratamiento , Insuficiencia del Tratamiento , Pérdida Auditiva/etiología , Estudios Retrospectivos , Estudios de Seguimiento
5.
Bioorg Med Chem Lett ; 29(6): 786-790, 2019 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-30728114

RESUMEN

The PD-1 immune checkpoint pathway is a highly validated target for cancer immunotherapy. Despite the potential advantages of small molecule inhibitors over antibodies, the discovery of small molecule checkpoint inhibitors has lagged behind. To discover small molecule inhibitors of the PD-1 pathway, we have utilized a fragment-based approach. Small molecules were identified that bind to PD-L1 and crystal structures of these compounds bound to PD-L1 were obtained.


Asunto(s)
Antígeno B7-H1/metabolismo , Bibliotecas de Moléculas Pequeñas/metabolismo , Antígeno B7-H1/antagonistas & inhibidores , Antígeno B7-H1/química , Cristalografía por Rayos X , Humanos , Enlace de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Unión Proteica , Bibliotecas de Moléculas Pequeñas/química
6.
Biochemistry ; 57(32): 4952-4958, 2018 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-30011190

RESUMEN

To test for on target toxicity of a new chemical entity, it is important to have comparable binding affinities of the compound in the target proteins from humans and the test species. To evaluate our myeloid cell leukemia-1 (Mcl-1) inhibitors, we tested them against rodent Mcl-1 and found a significant loss of binding affinity when compared to that seen with human Mcl-1. To understand the affinity loss, we used sequence alignments and structures of human Mcl-1/inhibitor complexes to identify the important differences in the amino acid sequences. One difference is human L246 (F226 in rat, F227 in mouse) in the ligand binding pocket. Mutating rat F226 to a Leu restores affinity, but the mouse F227L mutant still has a ligand affinity that is lower than that of human Mcl-1. Another mutation of mouse F267, located ∼12 Šfrom the ligand pocket, to the human/rat cysteine, F267C, improved the affinity and combined with F227L resulted in a mutant mouse protein with a binding affinity similar to that of human Mcl-1. To help understand the structural components of the affinity loss, we obtained an X-ray structure of a mouse Mcl-1/inhibitor complex and identified how the residue changes reduced compound complementarity. Finally, we tested Mcl-1 of other preclinical animal models (canine, monkey, rabbit, and ferret) that are identical to humans in terms of these two residues and found that their Mcl-1 bound our compounds with affinities comparable to that of human Mcl-1. These results have implications for understanding ligand selectivity for similar proteins and for the interpretation of preclinical toxicology studies with Mcl-1 inhibitors.


Asunto(s)
Proteína 1 de la Secuencia de Leucemia de Células Mieloides/química , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/metabolismo , Secuencia de Aminoácidos , Animales , Cristalografía por Rayos X , Perros , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Humanos , Ratones , Datos de Secuencia Molecular , Unión Proteica/efectos de los fármacos , Conejos , Ratas , Homología de Secuencia de Aminoácido , Relación Estructura-Actividad
7.
Anal Biochem ; 548: 44-52, 2018 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-29444450

RESUMEN

K-RAS is mutated in approximately 30% of human cancers, resulting in increased RAS signaling and tumor growth. Thus, RAS is a highly validated therapeutic target, especially in tumors of the pancreas, lung and colon. Although directly targeting RAS has proven to be challenging, it may be possible to target other proteins involved in RAS signaling, such as the guanine nucleotide exchange factor Son of Sevenless (SOS). We have previously reported on the discovery of small molecules that bind to SOS1, activate SOS-mediated nucleotide exchange on RAS, and paradoxically inhibit ERK phosphorylation (Burns et al., PNAS, 2014). Here, we describe the discovery of additional, structurally diverse small molecules that also bind to SOS1 in the same pocket and elicit similar biological effects. We tested >160,000 compounds in a fluorescence-based assay to assess their effects on SOS-mediated nucleotide exchange. X-Ray structures revealed that these small molecules bind to the CDC25 domain of SOS1. Compounds that elicited high levels of nucleotide exchange activity in vitro increased RAS-GTP levels in cells, and inhibited phospho ERK levels at higher treatment concentrations. The identification of structurally diverse SOS1 binding ligands may assist in the discovery of new molecules designed to target RAS-driven tumors.


Asunto(s)
Sistema de Señalización de MAP Quinasas , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Proteína SOS1/metabolismo , Células HeLa , Humanos , Proteínas Proto-Oncogénicas p21(ras)/química , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteína SOS1/química , Proteína SOS1/genética
8.
Childs Nerv Syst ; 34(4): 765-770, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29209883

RESUMEN

CASE PRESENTATION: An 11-year-old boy presented with a complaint of a painful temporal mass. Brain magnetic resonance imaging (MRI) showed a 3-cm-sized, homogeneously enhancing mass in the greater wing of the left sphenoid bone, which was diagnosed as Langerhans cell histiocytosis (LCH). Chemotherapy with vincristine and prednisolone was performed for 1 year. After 1 year and 11 months off treatment, he developed symptoms such as polydipsia and polyuria. Brain MRI showed thickening of the pituitary stalk with enhancement, suggestive of LCH involvement, and no recurrence in the sphenoid bone. After 4 years and 4 months off treatment, he developed multiple, subcutaneous, asymptomatic, and yellowish variable-sized papules on his face, posterior neck, and back, which were pathologically diagnosed as juvenile xanthogranuloma (JXG). Brain MRI revealed multifocal enhancing skull lesions in the left parietal, right frontal, and left occipital bones, which were also diagnosed as JXG. After 5 years and 8 months off treatment, the number of variable-sized skin lesions was increased without changes in the lesions in the skull and pituitary stalk. CONCLUSION: We report a case of disseminated JXG occurring after treatment of LCH. These clinical co-presentations suggested a close relationship between their pathogenesis.


Asunto(s)
Antineoplásicos/efectos adversos , Histiocitosis de Células de Langerhans/tratamiento farmacológico , Xantogranuloma Juvenil/inducido químicamente , Antígenos CD/metabolismo , Antígenos de Diferenciación Mielomonocítica/metabolismo , Encéfalo/diagnóstico por imagen , Niño , Estudios de Seguimiento , Histiocitosis de Células de Langerhans/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Masculino , Prednisolona/efectos adversos , Vincristina/efectos adversos , Xantogranuloma Juvenil/diagnóstico por imagen
9.
Bioorg Med Chem ; 25(12): 3087-3092, 2017 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-28428041

RESUMEN

Amplification of the gene encoding Myeloid cell leukemia-1 (Mcl-1) is one of the most common genetic aberrations in human cancer and is associated with high tumor grade and poor survival. Recently, we reported on the discovery of high affinity Mcl-1 inhibitors that elicit mechanism-based cell activity. These inhibitors are lipophilic and contain an acidic functionality which is a common chemical profile for compounds that bind to albumin in plasma. Indeed, these Mcl-1 inhibitors exhibited reduced in vitro cell activity in the presence of serum. Here we describe the structure of a lead Mcl-1 inhibitor when bound to Human Serum Albumin (HSA). Unlike many acidic lipophilic compounds that bind to drug site 1 or 2, we found that this Mcl-1 inhibitor binds predominantly to drug site 3. Site 3 of HSA may be able to accommodate larger, more rigid compounds that do not fit into the smaller drug site 1 or 2. Structural studies of molecules that bind to this third site may provide insight into how some higher molecular weight compounds bind to albumin and could be used to aid in the design of compounds with reduced albumin binding.


Asunto(s)
Proteína 1 de la Secuencia de Leucemia de Células Mieloides/antagonistas & inhibidores , Albúmina Sérica/metabolismo , Sitios de Unión , Línea Celular , Cristalografía por Rayos X , Humanos , Ligandos , Simulación del Acoplamiento Molecular , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/metabolismo , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Unión Proteica , Albúmina Sérica/química
10.
Proc Natl Acad Sci U S A ; 111(9): 3401-6, 2014 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-24550516

RESUMEN

Aberrant activation of the small GTPase Ras by oncogenic mutation or constitutively active upstream receptor tyrosine kinases results in the deregulation of cellular signals governing growth and survival in ∼30% of all human cancers. However, the discovery of potent inhibitors of Ras has been difficult to achieve. Here, we report the identification of small molecules that bind to a unique pocket on the Ras:Son of Sevenless (SOS):Ras complex, increase the rate of SOS-catalyzed nucleotide exchange in vitro, and modulate Ras signaling pathways in cells. X-ray crystallography of Ras:SOS:Ras in complex with these molecules reveals that the compounds bind in a hydrophobic pocket in the CDC25 domain of SOS adjacent to the Switch II region of Ras. The structure-activity relationships exhibited by these compounds can be rationalized on the basis of multiple X-ray cocrystal structures. Mutational analyses confirmed the functional relevance of this binding site and showed it to be essential for compound activity. These molecules increase Ras-GTP levels and disrupt MAPK and PI3K signaling in cells at low micromolar concentrations. These small molecules represent tools to study the acute activation of Ras and highlight a pocket on SOS that may be exploited to modulate Ras signaling.


Asunto(s)
Indoles/metabolismo , Modelos Moleculares , Complejos Multiproteicos/metabolismo , Piperidinas/metabolismo , Conformación Proteica , Proteínas Proto-Oncogénicas p21(ras)/antagonistas & inhibidores , Proteína SOS1/metabolismo , Cromatografía Liquida , Cromatografía en Capa Delgada , Cristalografía por Rayos X , Polarización de Fluorescencia , Células HeLa , Humanos , Ligandos , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Estructura Molecular , Complejos Multiproteicos/química , Proteínas Proto-Oncogénicas p21(ras)/química , Proteína SOS1/química
11.
Acta Neurochir (Wien) ; 157(3): 389-98, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25585838

RESUMEN

BACKGROUND: IA-Tx and advanced dynamic imaging studies have been adopted for ischemic stroke patient treatment. Many patients are treated with IV-tPA, but this treatment is not always feasible. In this study, IA-Tx was used for patients for whom IV-tPA was not indicated or when IV-tPA did not result in recanalization. METHODS: A total of 156 patients treated with IA-Tx were retrospectively reviewed. Of these, 72 patients were treated with a full dose of IV-tPA before receiving the IA-Tx; the remaining 84 patients only received IA-Tx. An initial imaging study using CTA and acute stroke MRI followed. Patients' demographics and clinical results were recorded and compared according to P/D mismatching and IV-tPA. RESULTS: Among P/D-mismatched patients, the recanalization rate was 80 % and the symptomatic intracranial hemorrhage rate was 14.5 %, while among P/D-matched patients, the rates were 63 % and 41.3 % respectively (p < 0.05). A favorable clinical outcome occurred in 49.1 % of P/D-mismatched, but only in 21.7 % of P/D-matched patients (p < 0.05). Among patients who were treated with IV-tPA before undergoing IA-Tx, the recanalization rate was 79.2 % and the sICH rate was 27.8 %, while it was 71.4 % and 17.9 % in patients who did not receive IV-tPA (p < 0.05). CONCLUSIONS: Patients who have P/D mismatching and are treated with IA-Tx have higher recanalization rates and a greater probability of a favorable outcome than patients who have P/D matching and receive IA-Tx. For patients who do not undergo successful recanalization after IV-tPA or who are not indicated for IV-tPA, the authors recommend IA-Tx after undergoing appropriate imaging evaluation.


Asunto(s)
Isquemia Encefálica/tratamiento farmacológico , Imagen de Difusión por Resonancia Magnética , Accidente Cerebrovascular/tratamiento farmacológico , Terapia Trombolítica/métodos , Anciano , Isquemia Encefálica/diagnóstico , Femenino , Fibrinolíticos/administración & dosificación , Fibrinolíticos/uso terapéutico , Humanos , Infusiones Intravenosas , Inyecciones Intravenosas , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Accidente Cerebrovascular/diagnóstico , Terapia Trombolítica/efectos adversos , Activador de Tejido Plasminógeno/administración & dosificación , Activador de Tejido Plasminógeno/uso terapéutico
12.
World Neurosurg ; 187: e199-e209, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38641244

RESUMEN

BACKGROUND: The development of artificial intelligence (AI) raises ethical concerns about its side effects on the attitudes and behaviors of clinicians and medical practitioners. The authors aim to understand the medical ethics of AI-based chatbots and to suggest coping strategies for an emerging landscape of increased access and potential ambiguity using AI. METHODS: This study examines the medical ethics of AI-based chatbots (Chat generative pretrained transformer [GPT], Bing Chat, and Google's Bard) using multiple-choice questions. ChatGPT and Bard correctly answered all questions (5/5), while Bing Chat correctly answered only 3 of 5 questions. ChatGPT explained answers simply. Bing Chat explained answers with references, and Bard provided additional explanations with details. RESULTS: AI has the potential to revolutionize medical fields by improving diagnosis accuracy, surgical planning, and treatment outcomes. By analyzing large amounts of data, AI can identify patterns and make predictions, aiding neurosurgeons in making informed decisions for increased patient wellbeing. As AI usage increases, the number of cases involving AI-entrusted judgments will rise, leading to the gradual emergence of ethical issues across interdisciplinary fields. The medical field will be no exception. CONCLUSIONS: This study suggests the need for safety measures to regulate medical ethics in the context of advancing AI. A system should be developed to verify and predict pertinent issues.


Asunto(s)
Inteligencia Artificial , Ética Médica , Neurocirugia , Inteligencia Artificial/ética , Humanos , Neurocirugia/ética , Neurocirujanos/ética , Procedimientos Neuroquirúrgicos/ética
13.
J Korean Neurosurg Soc ; 67(2): 249-256, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38211582

RESUMEN

The Leksell frame-based transcerebellar approach was proposed with the arc support frame attached upside down to the Z coordinate. This study presented practical tips and considerations for obtaining adequate tissue samples for deep-seated cerebellar lesions or lower brainstem lesions specifically those accessible via the cerebellar peduncle. For practical insights, the Leksell coordinate frame G was fixed to prevent the anterior screw implantation within the temporalis muscle, to avoid interference with the magnetic resonance (MR)-adapter, and taking into account the magnetic field of MR in close proximity to the tentorium. After mounting of indicator box, the MR imaging evaluation should cover both the indicator box and the infratentorial region that deviated from it. The coordinates [X, Y, Za, Arc0, Ringa0] obtained from Leksell SurgiPlan® software (Elekta, Stockholm, Sweden) with arc 00 located on the patient's right side were converted to [X, Y, Zb=360-Za, Arc0, Ringb0=Ringa0-1800]. The operation was performed in the prone position under general anesthesia in four patients with deep cerebellar (n=3) and brainstem (n=1) tumors. The biopsy results showed two cases of diffuse large B-cell lymphoma, one metastatic braintumor and one glioblastoma. One patient required frame repositioning as a complication. Drawing upon the methodology outlined in existing literature, we anticipate that imparting supplementary expertise could render the stereotactic biopsy of infratentorial tumors more consistent and manageable for the practitioner, thereby facilitating adequate tissue samples and minimizing patient complications.

14.
Elife ; 122024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38682900

RESUMEN

The chromatin-associated protein WD Repeat Domain 5 (WDR5) is a promising target for cancer drug discovery, with most efforts blocking an arginine-binding cavity on the protein called the 'WIN' site that tethers WDR5 to chromatin. WIN site inhibitors (WINi) are active against multiple cancer cell types in vitro, the most notable of which are those derived from MLL-rearranged (MLLr) leukemias. Peptidomimetic WINi were originally proposed to inhibit MLLr cells via dysregulation of genes connected to hematopoietic stem cell expansion. Our discovery and interrogation of small-molecule WINi, however, revealed that they act in MLLr cell lines to suppress ribosome protein gene (RPG) transcription, induce nucleolar stress, and activate p53. Because there is no precedent for an anticancer strategy that specifically targets RPG expression, we took an integrated multi-omics approach to further interrogate the mechanism of action of WINi in human MLLr cancer cells. We show that WINi induce depletion of the stock of ribosomes, accompanied by a broad yet modest translational choke and changes in alternative mRNA splicing that inactivate the p53 antagonist MDM4. We also show that WINi are synergistic with agents including venetoclax and BET-bromodomain inhibitors. Together, these studies reinforce the concept that WINi are a novel type of ribosome-directed anticancer therapy and provide a resource to support their clinical implementation in MLLr leukemias and other malignancies.


Asunto(s)
Péptidos y Proteínas de Señalización Intracelular , Proteína de la Leucemia Mieloide-Linfoide , Proteínas Nucleares , Ribosomas , Proteína p53 Supresora de Tumor , Humanos , Antineoplásicos/farmacología , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Línea Celular Tumoral , N-Metiltransferasa de Histona-Lisina/metabolismo , N-Metiltransferasa de Histona-Lisina/genética , Péptidos y Proteínas de Señalización Intracelular/antagonistas & inhibidores , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteína de la Leucemia Mieloide-Linfoide/metabolismo , Proteína de la Leucemia Mieloide-Linfoide/genética , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Ribosomas/efectos de los fármacos , Ribosomas/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/genética , Peptidomiméticos/farmacología
15.
bioRxiv ; 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-37546802

RESUMEN

The chromatin-associated protein WD Repeat Domain 5 (WDR5) is a promising target for cancer drug discovery, with most efforts blocking an arginine-binding cavity on the protein called the "WIN" site that tethers WDR5 to chromatin. WIN site inhibitors (WINi) are active against multiple cancer cell types in vitro, the most notable of which are those derived from MLL-rearranged (MLLr) leukemias. Peptidomimetic WINi were originally proposed to inhibit MLLr cells via dysregulation of genes connected to hematopoietic stem cell expansion. Our discovery and interrogation of small molecule WIN site inhibitors, however, revealed that they act in MLLr cell lines to suppress ribosome protein gene (RPG) transcription, induce nucleolar stress, and activate p53. Because there is no precedent for an anti-cancer strategy that specifically targets RPG expression, we took an integrated multi-omics approach to further interrogate the mechanism of action of WINi in MLLr cancer cells. We show that WINi induce depletion of the stock of ribosomes, accompanied by a broad yet modest translational choke and changes in alternative mRNA splicing that inactivate the p53 antagonist MDM4. We also show that WINi are synergistic with agents including venetoclax and BET-bromodomain inhibitors. Together, these studies reinforce the concept that WINi are a novel type of ribosome-directed anti-cancer therapy and provide a resource to support their clinical implementation in MLLr leukemias and other malignancies.

16.
J Korean Neurosurg Soc ; 66(5): 573-581, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37667635

RESUMEN

OBJECTIVE: Due to the implementation of vaccinations and the development of therapeutic agents, the coronavirus disease 2019 (COVID-19) pandemic that started at the end of 2019 has entered a new phase. As a result, neurosurgeons should reconsider the way they treat their patients. As the COVID-19 situation prolongs, the change in neurosurgical emergency patients according to the number of confirmed cases is no longer clear. Outpatient treatment by telephone was permitted according to government policy. In addition, visits to caregivers in the intensive care unit were limited. METHODS: The electronic medical records of patients who had been treated over the phone for a month (during April 2020, while the hospital was closing) were reviewed. Meanwhile, according to the limited visits to the intensive care unit, a video meeting was held with the caregivers. After the video meeting, satisfaction was evaluated using a questionnaire. RESULTS: During April 2020, 1021 patients received non-face-to-face care over the telephone. Among the patients, no critical medical problem occurred due to non-face-to-face care. From July 2021 to December 2021, 321 patients were admitted to the neurosurgical intensive care unit and 107 patients (33.3%) including their caregivers agreed to video visits. Twice a week, advance notice was given that access would be made through a mobile device and the nurse explained to caregivers how to use the mobile device. The time for the video meeting was approximately 20 minutes per patient. Based on the questionnaire, 81 respondents (75.7%) answered that they agreed, and 26 respondents (24.3%) answered that they strongly agreed that was easy to communicate through video meetings. Fifty-two (48.6%) agreed and 55 (51.4%) strongly agreed that they were easy to understand the doctor's explanation. For overall satisfaction with this video meeting, three respondents (2.8%) gave 4/5 points and 95 respondents (88.8%) gave 5/5 points, and nine (8.4%) gave 3/5 points. Their reason was that there was not enough time. CONCLUSION: In situations where patient visits are limited, video meetings through a mobile device can provide sufficient satisfaction to caregivers. Telemedicine will likely become common in the near future. Health care professionals should prepare and respond to these needs and changes. Therefore, establishing a system with institutional support is necessary.

17.
Brain Tumor Res Treat ; 11(3): 216-218, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37550822

RESUMEN

A 44-year-old female patient who had been diagnosed with breast cancer visited our oncology department. She had developed right-side weakness and mild dysarthria, and MRI revealed a 4-cm cystic-enhancing lesion in her left frontal lobe. Her surgery was postponed 48 hours after receiving 5-aminolevulinic acid (5-ALA), because a problem with thyroid function that had not been noticed before was discovered. The main lesion was enhanced on navigation and appeared to be a gross tumor; its 5-ALA uptake was very high. Specimens obtained from this location were histologically confirmed to contain tumor cells. The operation was completed, and removal of all enhancing lesions was confirmed by MRI within 24 hours postoperatively. The pathology report confirmed metastatic ductal carcinoma. The clinical efficacy of 5-ALA was confirmed even 48 hours after administration into a metastatic brain tumor from breast cancer.

18.
Brain Tumor Res Treat ; 11(2): 94-102, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37151151

RESUMEN

The paper provides a comprehensive overview of the growth and development of Hwasun Neurosurgery at Chonnam National University Hwasun Hospital over the past 18 years. As the first brain tumor center in Korea when it was established in April 2004, Hwasun Neurosurgery has since become one of the leading institutions in brain tumor education and research in the country. Its impressive clinical and basic research capabilities, dedication to professional education, and numerous academic achievements have all contributed to its reputation as a top-tier institution. We hope this will become a useful guide for other brain tumor centers or educational institutions by sharing the story of Hwasun Neurosurgery.

19.
J Med Chem ; 66(24): 16783-16806, 2023 12 28.
Artículo en Inglés | MEDLINE | ID: mdl-38085679

RESUMEN

The chromatin-associated protein WDR5 (WD repeat domain 5) is an essential cofactor for MYC and a conserved regulator of ribosome protein gene transcription. It is also a high-profile target for anti-cancer drug discovery, with proposed utility against both solid and hematological malignancies. We have previously discovered potent dihydroisoquinolinone-based WDR5 WIN-site inhibitors with demonstrated efficacy and safety in animal models. In this study, we sought to optimize the bicyclic core to discover a novel series of WDR5 WIN-site inhibitors with improved potency and physicochemical properties. We identified the 3,4-dihydrobenzo[f][1,4]oxazepin-5(2H)-one core as an alternative scaffold for potent WDR5 inhibitors. Additionally, we used X-ray structural analysis to design partially saturated bicyclic P7 units. These benzoxazepinone-based inhibitors exhibited increased cellular potency and selectivity and favorable physicochemical properties compared to our best-in-class dihydroisoquinolinone-based counterparts. This study opens avenues to discover more advanced WDR5 WIN-site inhibitors and supports their development as novel anti-cancer therapeutics.


Asunto(s)
Antineoplásicos , Repeticiones WD40 , Animales , Descubrimiento de Drogas , Antineoplásicos/farmacología
20.
J Clin Neurosci ; 98: 45-52, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35131724

RESUMEN

OBJECTIVE: Indocyanine green (ICG) has been used in endoscopic surgery in the neurosurgical field, but it has been challenging to determine the associated efficiency due to limitations with visualization in the previous endoscopic system. A new endoscopic system was recently introduced; therefore, we summarize our experiences with the application and integration of the system. METHODS: From March to June 2021, a newly introduced endoscopic system was used in 10 patients. (8 pituitary adenomas, and 2 tuberculum sellae meningiomas) and 12.5 mg of ICG was injected for each study. RESULTS: Six pituitary adenomas, including one acromegaly, were well identified with ICG. However, two pituitary adenomas, presented with apoplexy and two meningiomas were not visualized with ICG. CONCLUSIONS: The ICG provides real-time information during endoscopic endonasal surgery. We suggest that the pituitary adenoma can be stained with an ICG using the fusion-fluorescence imaging endoscopic system. This approach will enhance the surgeon's ability to remove the tumor with preserve the normal gland more safely.


Asunto(s)
Adenoma , Neoplasias Meníngeas , Meningioma , Neoplasias Hipofisarias , Adenoma/diagnóstico por imagen , Adenoma/cirugía , Humanos , Verde de Indocianina , Neoplasias Meníngeas/diagnóstico por imagen , Neoplasias Meníngeas/cirugía , Meningioma/diagnóstico por imagen , Meningioma/cirugía , Imagen Óptica , Neoplasias Hipofisarias/diagnóstico por imagen , Neoplasias Hipofisarias/patología , Neoplasias Hipofisarias/cirugía
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