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1.
Blood ; 138(13): 1148-1161, 2021 09 30.
Artículo en Inglés | MEDLINE | ID: mdl-34125173

RESUMEN

Most patients with acute promyelocytic leukemia (APL) can be cured with combined all-trans retinoic acid (ATRA) and arsenic trioxide therapy, which induces the destruction of PML-RARA, the initiating fusion protein for this disease. However, the underlying mechanisms by which PML-RARA initiates and maintains APL cells are still not clear. Therefore, we identified genes that are dysregulated by PML-RARA in mouse and human APL cells and prioritized GATA2 for functional studies because it is highly expressed in preleukemic cells expressing PML-RARA, its high expression persists in transformed APL cells, and spontaneous somatic mutations of GATA2 occur during APL progression in mice and humans. These and other findings suggested that GATA2 may be upregulated to thwart the proliferative signal generated by PML-RARA and that its inactivation by mutation (and/or epigenetic silencing) may accelerate disease progression in APL and other forms of acute myeloid leukemia (AML). Indeed, biallelic knockout of Gata2 with CRISPR/Cas9-mediated gene editing increased the serial replating efficiency of PML-RARA-expressing myeloid progenitors (as well as progenitors expressing RUNX1-RUNX1T1, or deficient for Cebpa), increased mouse APL penetrance, and decreased latency. Restoration of Gata2 expression suppressed PML-RARA-driven aberrant self-renewal and leukemogenesis. Conversely, addback of a mutant GATA2R362G protein associated with APL and AML minimally suppressed PML-RARA-induced aberrant self-renewal, suggesting that it is a loss-of-function mutation. These studies reveal a potential role for Gata2 as a tumor suppressor in AML and suggest that restoration of its function (when inactivated) may provide benefit for AML patients.


Asunto(s)
Factor de Transcripción GATA2/genética , Leucemia Promielocítica Aguda/genética , Animales , Sistemas CRISPR-Cas , Línea Celular Tumoral , Progresión de la Enfermedad , Factor de Transcripción GATA2/metabolismo , Regulación Leucémica de la Expresión Génica , Genes Supresores de Tumor , Humanos , Leucemia Promielocítica Aguda/metabolismo , Leucemia Promielocítica Aguda/patología , Ratones , Mutación
2.
AJR Am J Roentgenol ; 220(2): 202-211, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36000664

RESUMEN

BACKGROUND. Suspicious lesions detected on contrast-enhanced breast MRI often undergo targeted ultrasound evaluation to determine whether they are amenable to ultrasound-guided biopsy. OBJECTIVE. The purpose of this study is to assess the utility of MRI-directed contrast-enhanced mammography (CEM) performed for biopsy planning for suspicious MRI-detected breast lesions and to compare its use with that of MRI-directed ultrasound. METHODS. This retrospective study included 120 patients (median age, 50.3 years) who underwent MRI-directed CEM from September 2014 to July 2020 for biopsy planning for a total of 140 suspicious breast MRI lesions; 109 lesions were also evaluated by MRI-directed ultrasound at the same visit. The reference standard was histopathology or at least 2 years of imaging follow-up for benign lesions. Rates of detecting a correlate for the MRI lesion, among all lesions and among malignant lesions, were compared between MRI-directed CEM, MRI-directed ultrasound, and combined MRI-directed CEM and ultrasound (i.e., with the correlate detected on either modality), by use of the McNemar test. The frequencies with which imaging modalities were used for biopsy guidance after MRI-directed imaging were determined. RESULTS. Twenty-three of 109 lesions were malignant. The lesion detection rate was higher for MRI-directed CEM than for MRI-directed ultrasound (69.7% [76/109] vs 45.9% [50/109]; p < .001) and higher for combined MRI-directed CEM and ultrasound (77.1% [84/109]) than for either MRI-directed CEM (p = .008) or MRI-directed ultrasound (p < .001). The rate of detection of malignant lesions was not significantly different between MRI-directed CEM and MRI-directed ultrasound (95.7% [22/23] vs 78.3% [18/23]; p = .13). A total of 31.2% (34/109) of lesions were seen on MRI-directed CEM only, and 7.3% (8/109) were seen on MRI-directed ultrasound only. A total of 17.4% (4/23) of malignant lesions were seen on MRI-directed CEM only, and none were seen on MRI-directed ultrasound only. Among lesions recommended for biopsy, stereotactic- or tomosynthesis-guided biopsy was recommended for 25.2% (26/103), ultrasound-guided biopsy for 35.9% (37/103), and MRI-guided biopsy for 38.8% (40/103). CONCLUSION. MRI-directed CEM detects a higher fraction of suspicious MRI lesions than does MRI-directed ultrasound. Combined MRI-directed CEM and ultrasound detects a higher fraction than either method does individually. CLINICAL IMPACT. MRI-directed CEM may be a useful alternate or complementary tool to MRI-directed ultrasound in biopsy planning for suspicious MRI lesions, facilitating the use of biopsy guidance methods other than MRI guidance.


Asunto(s)
Neoplasias de la Mama , Medios de Contraste , Humanos , Persona de Mediana Edad , Femenino , Estudios Retrospectivos , Biopsia , Mamografía , Imagen por Resonancia Magnética/métodos , Biopsia Guiada por Imagen , Neoplasias de la Mama/diagnóstico por imagen
3.
J Arthroplasty ; 36(7S): S328-S331, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33888386

RESUMEN

BACKGROUND: Venous thromboembolism (VTE) is a serious complication of total hip arthroplasty (THA) and total knee arthroplasty (TKA). Apixaban is approved for VTE prophylaxis. This study seeks to ascertain the risk of VTE and bleeding complications in patients undergoing primary THA and TKA receiving apixaban for postoperative VTE prophylaxis for one of the following indications: high risk for VTE, previously on apixaban, and contraindication to the use of aspirin. METHODS: This is a retrospective cohort study of patients who underwent primary THA or TKA over a 17-month period and were prescribed apixaban for thromboprophylaxis postoperatively. RESULTS: 230 patients were included in the study, 110 TKA and 120 THA. The primary reasons for high-risk VTE status included personal and family history of VTE, and 13% were taking apixaban preoperatively for atrial fibrillation. 1 patient (0.43%) who underwent TKA had a DVT with PE. 2.6% of patients had wound complications requiring operative treatment, and 0.87% of THA patients underwent revision arthroplasty. CONCLUSION: The use of apixaban for VTE prophylaxis after primary THA and TKA in patients at high risk for VTE, in patients previously on apixaban, and in patients with a contraindication to the use of aspirin is associated with a low risk of VTE and bleeding complications.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Artroplastia de Reemplazo de Rodilla , Tromboembolia Venosa , Anticoagulantes , Artroplastia de Reemplazo de Cadera/efectos adversos , Artroplastia de Reemplazo de Rodilla/efectos adversos , Humanos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/prevención & control , Pirazoles , Piridonas , Estudios Retrospectivos , Tromboembolia Venosa/epidemiología , Tromboembolia Venosa/etiología , Tromboembolia Venosa/prevención & control
4.
Breast Cancer Res Treat ; 183(2): 403-410, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32656723

RESUMEN

PURPOSE: Little is known about the three-dimensional shape of breast cancer. Implicit to approaches that localize the center of the tumor for breast-conserving surgery (BCS) of non-palpable cancers is the assumption that breast cancers are spherical about a central point, which may not be accurate. METHODS: Pre-operative supine breast MRI images were obtained of 83 breast cancer patients undergoing partial mastectomy using supine MRI-guided resection techniques. Three-dimensional (3D) tumor models were derived after radiologists outlined tumor edges on successive MRI slices. Ideal resection volumes were determined by adding 1 cm in every dimension to the actual tumor volume. Geometrically defined parameters were used to define tumor shapes and associations between clinical variables and shapes were examined. RESULTS: Seventy-five patients had invasive cancer. Breast cancers were categorized into four tumor shapes: 34% of tumors were discoidal, 29% segmental, 19% spherical, and 18% irregular. If hypothetical spherical excisions were performed, non-spherical cases would excise 143% more tissue than the ideal resection volume. When the 3D shape of each tumor was provided to the surgeon during MR-guided BCS, the percentage of tissue overexcised in non-spherical cases was significantly less (143% vs. 66%, p < 0.001). CONCLUSIONS: Information obtained from a supine MRI can be used to generate 3D tumor models and rapidly classify breast tumor shapes. The vast majority of invasive cancers and DCIS are not spherical. Knowledge of tumor shape may allow surgeons to excise breast cancer more precisely.


Asunto(s)
Neoplasias de la Mama/patología , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética/métodos , Mastectomía Segmentaria/métodos , Mastectomía/métodos , Carga Tumoral , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/cirugía , Femenino , Humanos , Persona de Mediana Edad
5.
Ann Surg Oncol ; 26(10): 3099-3108, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31359283

RESUMEN

BACKGROUND: Wire-localized excision of non-palpable breast cancer is imprecise, resulting in positive margins 15-35% of the time. METHODS: Women with a confirmed diagnosis of non-palpable invasive breast cancer (IBC) or ductal carcinoma in situ (DCIS) were randomized to a new technique using preoperative supine magnetic resonance imaging (MRI) with intraoperative optical scanning and tracking (MRI group) or wire-localized (WL group) partial mastectomy. The main outcome measure was the positive margin rate. RESULTS: In this study, 138 patients were randomly assigned. Sixty-six percent had IBC and DCIS, 22% had IBC, and 12% had DCIS. There were no differences in patient or tumor characteristics between the groups. The proportion of patients with positive margins in the MRI-guided surgery group was half that observed in the WL group (12 vs. 23%; p = 0.08). The specimen volumes in the MRI and WL groups did not differ significantly (74 ± 33.9 mL vs. 69.8 ± 25.1 mL; p = 0.45). The pathologic tumor diameters were underestimated by 2 cm or more in 4% of the cases by MRI and in 9% of the cases by mammography. Positive margins were observed in 68% and 58% of the cases underestimated by 2 cm or more using MRI and mammography, respectively, and in 15% and 14% of the cases not underestimated using MRI and mammography, respectively. CONCLUSIONS: A novel system using supine MRI images co-registered with intraoperative optical scanning and tracking enabled tumors to be resected with a trend toward a lower positive margin rate compared with wire-localized partial mastectomy. Margin positivity was more likely when imaging underestimated pathologic tumor size.


Asunto(s)
Neoplasias de la Mama/cirugía , Carcinoma Ductal de Mama/cirugía , Carcinoma Intraductal no Infiltrante/cirugía , Carcinoma Lobular/cirugía , Imagen por Resonancia Magnética/métodos , Mamografía/métodos , Mastectomía Segmentaria/métodos , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/patología , Carcinoma Intraductal no Infiltrante/patología , Carcinoma Lobular/patología , Femenino , Estudios de Seguimiento , Humanos , Márgenes de Escisión , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos
6.
Ann Surg Oncol ; 24(10): 2950-2956, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28766199

RESUMEN

BACKGROUND: Wire-localized excision of nonpalpable breast cancer is imprecise, resulting in positive margins 25-30% of the time. METHODS: Patients underwent preoperative supine magnetic resonance imaging (MRI). A radiologist outlined the tumor edges on consecutive images, creating a three-dimensional (3D) view of its location. Using 3D printing, a bra-like plastic form (the Breast Cancer Locator [BCL]) was fabricated, with features that allowed a surgeon to (1) mark the edges of the tumor on the breast surface; (2) inject blue dye into the breast 1 cm from the tumor edges; and (3) place a wire in the tumor at the time of surgery. RESULTS: Nineteen patients with palpable cancers underwent partial mastectomy after placement of surgical cues using patient-specific BCLs. The cues were in place in <5 min and no adverse events occurred. The BCL accurately localized 18/19 cancers. In the 18 accurately localized cases, all 68 blue-dye injections were outside of the tumor edges. Median distance from the blue-dye center to the pathologic tumor edge was 1.4 cm, while distance from the blue dye to the tumor edge was <5 mm in 4% of injections, 0.5-2.0 cm in 72% of injections, and >2 cm in 24% of injections. Median distance from the tumor center to the BCL-localized wire and to the clip placed at the time of diagnosis was similar (0.49 vs. 0.73 cm) on specimen mammograms. CONCLUSIONS: Information on breast cancer location and shape derived from a supine MRI can be transferred safely and accurately to patients in the operating room using a 3D-printed form.


Asunto(s)
Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/patología , Carcinoma Intraductal no Infiltrante/patología , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética/métodos , Mastectomía Segmentaria , Cirugía Asistida por Computador/métodos , Neoplasias de la Mama/cirugía , Carcinoma Ductal de Mama/cirugía , Carcinoma Intraductal no Infiltrante/cirugía , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Invasividad Neoplásica , Estadificación de Neoplasias , Posición Supina
7.
Angew Chem Int Ed Engl ; 55(29): 8353-7, 2016 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-27264992

RESUMEN

A range of isoxazole-containing amino acids was synthesized that displaced acetyl-lysine-containing peptides from the BAZ2A, BRD4(1), and BRD9 bromodomains. Three of these amino acids were incorporated into a histone H4-mimicking peptide and their affinity for BRD4(1) was assessed. Affinities of the isoxazole-containing peptides are comparable to those of a hyperacetylated histone H4-mimicking cognate peptide, and demonstrated a dependence on the position at which the unnatural residue was incorporated. An isoxazole-based alkylating agent was developed to selectively alkylate cysteine residues in situ. Selective monoalkylation of a histone H4-mimicking peptide, containing a lysine to cysteine residue substitution (K12C), resulted in acetyl-lysine mimic incorporation, with high affinity for the BRD4 bromodomain. The same technology was used to alkylate a K18C mutant of histone H3.

8.
PLoS Genet ; 8(8): e1002936, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22952455

RESUMEN

Degeneration of synaptic and axonal compartments of neurons is an early event contributing to the pathogenesis of many neurodegenerative diseases, but the underlying molecular mechanisms remain unclear. Here, we demonstrate the effectiveness of a novel "top-down" approach for identifying proteins and functional pathways regulating neurodegeneration in distal compartments of neurons. A series of comparative quantitative proteomic screens on synapse-enriched fractions isolated from the mouse brain following injury identified dynamic perturbations occurring within the proteome during both initiation and onset phases of degeneration. In silico analyses highlighted significant clustering of proteins contributing to functional pathways regulating synaptic transmission and neurite development. Molecular markers of degeneration were conserved in injury and disease, with comparable responses observed in synapse-enriched fractions isolated from mouse models of Huntington's disease (HD) and spinocerebellar ataxia type 5. An initial screen targeting thirteen degeneration-associated proteins using mutant Drosophila lines revealed six potential regulators of synaptic and axonal degeneration in vivo. Mutations in CALB2, ROCK2, DNAJC5/CSP, and HIBCH partially delayed injury-induced neurodegeneration. Conversely, mutations in DNAJC6 and ALDHA1 led to spontaneous degeneration of distal axons and synapses. A more detailed genetic analysis of DNAJC5/CSP mutants confirmed that loss of DNAJC5/CSP was neuroprotective, robustly delaying degeneration in axonal and synaptic compartments. Our study has identified conserved molecular responses occurring within synapse-enriched fractions of the mouse brain during the early stages of neurodegeneration, focused on functional networks modulating synaptic transmission and incorporating molecular chaperones, cytoskeletal modifiers, and calcium-binding proteins. We propose that the proteins and functional pathways identified in the current study represent attractive targets for developing therapeutics aimed at modulating synaptic and axonal stability and neurodegeneration in vivo.


Asunto(s)
Lesiones Encefálicas , Drosophila , Degeneración Nerviosa , Sinapsis , Aldehído Deshidrogenasa/genética , Aldehído Deshidrogenasa/metabolismo , Animales , Axones/metabolismo , Axones/patología , Axones/fisiología , Lesiones Encefálicas/metabolismo , Lesiones Encefálicas/patología , Calbindina 2 , Drosophila/genética , Drosophila/fisiología , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Proteínas del Choque Térmico HSP40/genética , Proteínas del Choque Térmico HSP40/metabolismo , Enfermedad de Huntington/genética , Enfermedad de Huntington/metabolismo , Ratones , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Mutación , Degeneración Nerviosa/metabolismo , Degeneración Nerviosa/patología , Proteómica , Proteína G de Unión al Calcio S100/genética , Proteína G de Unión al Calcio S100/metabolismo , Ataxias Espinocerebelosas/genética , Ataxias Espinocerebelosas/metabolismo , Sinapsis/metabolismo , Sinapsis/patología , Tioléster Hidrolasas/genética , Tioléster Hidrolasas/metabolismo , Degeneración Walleriana/metabolismo , Degeneración Walleriana/patología , Quinasas Asociadas a rho/genética , Quinasas Asociadas a rho/metabolismo
9.
J Am Chem Soc ; 136(26): 9308-19, 2014 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-24946055

RESUMEN

Small-molecule inhibitors that target bromodomains outside of the bromodomain and extra-terminal (BET) sub-family are lacking. Here, we describe highly potent and selective ligands for the bromodomain module of the human lysine acetyl transferase CBP/p300, developed from a series of 5-isoxazolyl-benzimidazoles. Our starting point was a fragment hit, which was optimized into a more potent and selective lead using parallel synthesis employing Suzuki couplings, benzimidazole-forming reactions, and reductive aminations. The selectivity of the lead compound against other bromodomain family members was investigated using a thermal stability assay, which revealed some inhibition of the structurally related BET family members. To address the BET selectivity issue, X-ray crystal structures of the lead compound bound to the CREB binding protein (CBP) and the first bromodomain of BRD4 (BRD4(1)) were used to guide the design of more selective compounds. The crystal structures obtained revealed two distinct binding modes. By varying the aryl substitution pattern and developing conformationally constrained analogues, selectivity for CBP over BRD4(1) was increased. The optimized compound is highly potent (Kd = 21 nM) and selective, displaying 40-fold selectivity over BRD4(1). Cellular activity was demonstrated using fluorescence recovery after photo-bleaching (FRAP) and a p53 reporter assay. The optimized compounds are cell-active and have nanomolar affinity for CBP/p300; therefore, they should be useful in studies investigating the biological roles of CBP and p300 and to validate the CBP and p300 bromodomains as therapeutic targets.


Asunto(s)
Proteína de Unión a CREB/química , Proteína p300 Asociada a E1A/química , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/farmacología , Sitios de Unión , Proteína de Unión a CREB/genética , Proteína de Unión a CREB/metabolismo , Técnicas de Química Sintética , Cristalografía por Rayos X , Descubrimiento de Drogas , Evaluación Preclínica de Medicamentos/métodos , Proteína p300 Asociada a E1A/metabolismo , Recuperación de Fluorescencia tras Fotoblanqueo , Genes p53 , Células HeLa/efectos de los fármacos , Humanos , Indoles/química , Isoxazoles/química , Ligandos , Microsomas Hepáticos/efectos de los fármacos , Modelos Moleculares , Estructura Molecular , Estructura Terciaria de Proteína , Bibliotecas de Moléculas Pequeñas/metabolismo , Relación Estructura-Actividad
10.
Angew Chem Int Ed Engl ; 53(24): 6126-30, 2014 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-24821300

RESUMEN

The benzoxazinone and dihydroquinoxalinone fragments were employed as novel acetyl lysine mimics in the development of CREBBP bromodomain ligands. While the benzoxazinone series showed low affinity for the CREBBP bromodomain, expansion of the dihydroquinoxalinone series resulted in the first potent inhibitors of a bromodomain outside the BET family. Structural and computational studies reveal that an internal hydrogen bond stabilizes the protein-bound conformation of the dihydroquinoxalinone series. The side chain of this series binds in an induced-fit pocket forming a cation-π interaction with R1173 of CREBBP. The most potent compound inhibits binding of CREBBP to chromatin in U2OS cells.


Asunto(s)
Proteína de Unión a CREB/genética , Cationes/química , Epigenómica/métodos , Ligandos , Modelos Moleculares , Unión Proteica
11.
J Am Coll Radiol ; 21(8): 1208-1215, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38461915

RESUMEN

Breast cancer incidence and mortality continue to increase in Africa. In Tanzania, breast cancer is the second leading cause of cancer death for women, and breast cancer incidence and mortality are projected to increase by 80% by 2030. Education gaps among health care workers, delayed presentation, limited screening, and low health literacy all pose significant challenges to providing optimal breast cancer care. Considering these factors, it is imperative to train expert breast radiologists. We present a collaborative breast radiology training program in Tanzania aimed at building local capacity to address national breast cancer challenges. Although cancer control in Africa faces many challenges, developing customized training programs for breast radiology, in conjunction with national cancer programs, may represent a key strategy for addressing breast cancer.


Asunto(s)
Neoplasias de la Mama , Tanzanía , Humanos , Neoplasias de la Mama/diagnóstico por imagen , Femenino , Radiología/educación , Curriculum , Desarrollo de Programa , Detección Precoz del Cáncer
12.
J Breast Imaging ; 6(3): 277-287, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38537570

RESUMEN

OBJECTIVE: We investigated patient experience with screening contrast-enhanced mammography (CEM) to determine whether a general population of women with dense breasts would accept CEM in a screening setting. METHODS: In this institutional review board-approved prospective study, patients with heterogeneous and extremely dense breasts on their mammogram were invited to undergo screening CEM and complete pre-CEM and post-CEM surveys. On the pre-CEM survey, patients were asked about their attitudes regarding supplemental screening in general. On the post-CEM survey, patients were asked about their experience undergoing screening CEM, including causes and severity of any discomfort and whether they would consider undergoing screening CEM again in the future or recommend it to a friend. RESULTS: One hundred sixty-three women were surveyed before and after screening CEM. Most patients, 97.5% (159/163), reported minimal or no unpleasantness associated with undergoing screening CEM. In addition, 91.4% (149/163) said they would probably or very likely undergo screening CEM in the future if it cost the same as a traditional screening mammogram, and 95.1% (155/163) said they would probably or very likely recommend screening CEM to a friend. Patients in this study, who were all willing to undergo CEM, more frequently reported a family history of breast cancer than a comparison cohort of women with dense breasts (58.2% vs 47.1%, P = .027). CONCLUSION: Patients from a general population of women with dense breasts reported a positive experience undergoing screening CEM, suggesting screening CEM might be well received by this patient population, particularly if the cost was comparable with traditional screening mammography.


Asunto(s)
Densidad de la Mama , Neoplasias de la Mama , Medios de Contraste , Mamografía , Humanos , Femenino , Mamografía/métodos , Persona de Mediana Edad , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/diagnóstico , Medios de Contraste/administración & dosificación , Estudios Prospectivos , Anciano , Adulto , Detección Precoz del Cáncer/métodos , Encuestas y Cuestionarios , Mama/diagnóstico por imagen , Intensificación de Imagen Radiográfica/métodos , Tamizaje Masivo/métodos
13.
J Med Chem ; 67(17): 15521-15536, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39190548

RESUMEN

Aurora A kinase, a cell division regulator, is frequently overexpressed in various cancers, provoking genome instability and resistance to antimitotic chemotherapy. Localization and enzymatic activity of Aurora A are regulated by its interaction with the spindle assembly factor TPX2. We have used fragment-based, structure-guided lead discovery to develop small molecule inhibitors of the Aurora A-TPX2 protein-protein interaction (PPI). Our lead compound, CAM2602, inhibits Aurora A:TPX2 interaction, binding Aurora A with 19 nM affinity. CAM2602 exhibits oral bioavailability, causes pharmacodynamic biomarker modulation, and arrests the growth of tumor xenografts. CAM2602 acts by a novel mechanism compared to ATP-competitive inhibitors and is highly specific to Aurora A over Aurora B. Consistent with our finding that Aurora A overexpression drives taxane resistance, these inhibitors synergize with paclitaxel to suppress the outgrowth of pancreatic cancer cells. Our results provide a blueprint for targeting the Aurora A-TPX2 PPI for cancer therapy and suggest a promising clinical utility for this mode of action.


Asunto(s)
Antimitóticos , Aurora Quinasa A , Proteínas de Ciclo Celular , Proteínas Asociadas a Microtúbulos , Humanos , Animales , Aurora Quinasa A/antagonistas & inhibidores , Aurora Quinasa A/metabolismo , Proteínas de Ciclo Celular/antagonistas & inhibidores , Proteínas de Ciclo Celular/metabolismo , Antimitóticos/farmacología , Antimitóticos/química , Línea Celular Tumoral , Proteínas Asociadas a Microtúbulos/metabolismo , Ratones , Proteínas Nucleares/metabolismo , Proteínas Nucleares/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/química , Ensayos Antitumor por Modelo de Xenoinjerto , Antineoplásicos/farmacología , Antineoplásicos/química , Relación Estructura-Actividad , Paclitaxel/farmacología , Ratones Desnudos
14.
RSC Med Chem ; 14(10): 2035-2047, 2023 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-37859710

RESUMEN

The phosphatidylinositol 5-phosphate 4-kinases (PI5P4Ks) are therapeutic targets for diseases such as cancer, neurodegeneration and immunological disorders as they are key components in regulating cell signalling pathways. In an effort to make probe molecules available for further exploring these targets, we have previously reported PI5P4Kα-selective and PI5P4Kγ-selective ligands. Herein we report the rational design of PI5P4Kα/γ dual inhibitors, using knowledge gained during the development of selective inhibitors for these proteins. ARUK2007145 (39) is disclosed as a potent, cell-active probe molecule with ADMET properties amenable to conducting experiments in cells.

15.
Br J Pharmacol ; 180(1): 80-93, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36106615

RESUMEN

BACKGROUND AND PURPOSE: Small interfering RNA (siRNA) targeting liver angiotensinogen lowers blood pressure, but its effects in hypertensive diabetes are unknown. EXPERIMENTAL APPROACH: To address this, TGR (mRen2)27 rats (angiotensin II-dependent hypertension model) were made diabetic with streptozotocin over 18 weeks and treated with either vehicle, angiotensinogen siRNA, the AT1 antagonist valsartan, the ACE inhibitor captopril, valsartan + siRNA or valsartan + captopril for the final 3 weeks. Mean arterial pressure (MAP) was measured via radiotelemetry. KEY RESULTS: MAP before treatment was 153 ± 2 mmHg. Diabetes resulted in albuminuria, accompanied by glomerulosclerosis and podocyte effacement, without a change in glomerular filtration rate. All treatments lowered MAP and cardiac hypertrophy, and the largest drop in MAP was observed with siRNA + valsartan. Treatment with siRNA lowered circulating angiotensinogen by >99%, and the lowest circulating angiotensin II and aldosterone levels occurred in the dual treatment groups. Angiotensinogen siRNA did not affect renal angiotensinogen mRNA expression, confirming its liver-specificity. Furthermore, only siRNA with or without valsartan lowered renal angiotensin I. All treatments lowered renal angiotensin II and the reduction was largest (>95%) in the siRNA + valsartan group. All treatments identically lowered albuminuria, whereas only siRNA with or without valsartan restored podocyte foot processes and reduced glomerulosclerosis. CONCLUSION AND IMPLICATIONS: Angiotensinogen siRNA exerts renoprotection in diabetic TGR (mRen2)27 rats and this relies, at least in part, on the suppression of renal angiotensin II formation from liver-derived angiotensinogen. Clinical trials should now address whether this is also beneficial in human diabetic kidney disease.


Asunto(s)
Angiotensina II , Diabetes Mellitus Experimental , Hipertensión , Enfermedades Renales , ARN Interferente Pequeño , Animales , Humanos , Ratas , Albuminuria , Angiotensina II/efectos de los fármacos , Angiotensina II/genética , Presión Sanguínea/efectos de los fármacos , Presión Sanguínea/genética , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/metabolismo , Hipertensión/tratamiento farmacológico , Hígado/metabolismo , Renina/metabolismo , Sistema Renina-Angiotensina , Valsartán/farmacología , Enfermedades Renales/tratamiento farmacológico , Enfermedades Renales/metabolismo , Enfermedades Renales/prevención & control , ARN Interferente Pequeño/metabolismo , ARN Interferente Pequeño/farmacología , ARN Interferente Pequeño/uso terapéutico
16.
J Med Chem ; 66(1): 804-821, 2023 01 12.
Artículo en Inglés | MEDLINE | ID: mdl-36516442

RESUMEN

Owing to their central role in regulating cell signaling pathways, the phosphatidylinositol 5-phosphate 4-kinases (PI5P4Ks) are attractive therapeutic targets in diseases such as cancer, neurodegeneration, and immunological disorders. Until now, tool molecules for these kinases have been either limited in potency or isoform selectivity, which has hampered further investigation of biology and drug development. Herein we describe the virtual screening workflow which identified a series of thienylpyrimidines as PI5P4Kγ-selective inhibitors, as well as the medicinal chemistry optimization of this chemotype, to provide potent and selective tool molecules for further use. In vivo pharmacokinetics data are presented for exemplar tool molecules, along with an X-ray structure for ARUK2001607 (15) in complex with PI5P4Kγ, along with its selectivity data against >150 kinases and a Cerep safety panel.


Asunto(s)
Neoplasias , Transducción de Señal , Humanos , Isoformas de Proteínas , Encéfalo , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/química
17.
Radiol Case Rep ; 17(4): 1099-1103, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35169408

RESUMEN

Nipple discharge is a common complaint among adult women and is often evaluated by galactography. Contrast-enhanced mammography (CEM) is an emerging breast imaging modality that is useful in the evaluation of patients with nipple discharge who have a negative galactogram, especially if they are not good candidates for contrast-enhanced MRI. Here we present a case of a 37-year-old female who was 22 weeks pregnant and presented with suspicious nipple discharge. The patient initially underwent galactography, which was negative, and was subsequently referred for CEM for further evaluation. One week after the galactogram, the patient underwent CEM which revealed persistent intraductal iodinated contrast from the galactogram. The retained intraductal contrast obscured the area of concern on the CEM and limited evaluation for underlying areas of enhancement. Given the increasing popularity of CEM in breast imaging practice and its utility in the evaluation of patients with nipple discharge, recognition of retained intraductal contrast as a source of artifact on CEM is important so that steps can be taken to prevent acquiring a limited and/or non-diagnostic CEM. We suggest several practical steps the radiologist can take when planning the diagnostic workup of patients with nipple discharge to ensure the patient will be able to successfully undergo CEM, if needed. These steps will help reduce unnecessary patient exposure to radiation and intravenous contrast and avoid a delay in diagnosis and treatment.

18.
Acad Radiol ; 29(8): 1266-1274, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-34924281

RESUMEN

RATIONALE AND OBJECTIVES: To explore the effectiveness of the video medium and YouTube platform in conveying residency program and community information to prospective applicants during the 2020-2021 virtual residency interview cycle. To garner insights on the virtual-only residency interview experience and our video-centered approach through survey data collected from interviewing candidates for potential implementation in future application cycles. MATERIALS AND METHODS: 13 custom content videos were produced highlighting our radiology residency program and uploaded onto a newly created YouTube channel and the institutional website during the late summer through fall of the 2020-2021 residency interview cycle. Feedback on the videos was generated using YouTube analytics and an anonymous 10-question survey sent to interviewing candidates. RESULTS: As of September 29, 2021, the date when residency programs could begin reviewing ERAS applications for the 2021-2022 cycle, the videos amassed 4487 views with over 149 hours' worth of material viewed. 57 of 114 interviewed candidates responded to the survey. Feedback was overwhelmingly positive with 84% of respondents agreeing that the videos positively influenced their decision to apply to our program, 77% of respondents judging our video-based format to be overall more effective in delivering residency program information than text-based media (website, email etc.), and 86% feeling adequately informed about the program through the virtual interview process and provided electronic resources. 79% of respondents felt our videos to be more informative than the resources from other radiology programs encountered during the interviewing cycle. Finally, a majority 72% of respondents are open to virtual interviewing in the future. CONCLUSIONS: Our program's video-centered approach was one of many creative media solutions employed by residency programs across the nation to help make virtual interviewing an adequate replacement to the traditional in-person interviewing experience. While further investigation is needed to determine which methods communicate residency program information best in the virtual setting, our initial experience and data show the video-centered approach to be overwhelmingly positive with applicants and at a minimum, we've established a baseline process and aesthetic for others to improve upon.


Asunto(s)
Internado y Residencia , Radiología , Humanos , Selección de Personal , Estudios Prospectivos , Radiografía
19.
J Med Chem ; 65(4): 3359-3370, 2022 02 24.
Artículo en Inglés | MEDLINE | ID: mdl-35148092

RESUMEN

Phosphatidylinositol 5-phosphate 4-kinases (PI5P4Ks) are emerging as attractive therapeutic targets in diseases, such as cancer, immunological disorders, and neurodegeneration, owing to their central role in regulating cell signaling pathways that are either dysfunctional or can be modulated to promote cell survival. Different modes of binding may enhance inhibitor selectivity and reduce off-target effects in cells. Here, we describe efforts to improve the physicochemical properties of the selective PI5P4Kγ inhibitor, NIH-12848 (1). These improvements enabled the demonstration that this chemotype engages PI5P4Kγ in intact cells and that compounds from this series do not inhibit PI5P4Kα or PI5P4Kß. Furthermore, the first X-ray structure of PI5P4Kγ bound to an inhibitor has been determined with this chemotype, confirming an allosteric binding mode. An exemplar from this chemical series adopted two distinct modes of inhibition, including through binding to a putative lipid interaction site which is 18 Å from the ATP pocket.


Asunto(s)
Adenosina Trifosfato/metabolismo , Fosfotransferasas (Aceptor de Grupo Alcohol)/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/farmacología , Quinazolinas/síntesis química , Quinazolinas/farmacología , Tiofenos/síntesis química , Tiofenos/farmacología , Regulación Alostérica/efectos de los fármacos , Unión Competitiva , Cristalografía por Rayos X , Humanos , Modelos Moleculares , Simulación del Acoplamiento Molecular , Fosfotransferasas (Aceptor de Grupo Alcohol)/química , Especificidad por Sustrato
20.
Surg Oncol ; 44: 101843, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36067629

RESUMEN

BACKGROUND: Evaluate whether the Breast Cancer Locator™ (BCL), a novel guidance system based on supine MRI images, can be safely and effectively deployed by several surgeons at multiple sites. METHODS: Patients with palpable breast cancer underwent supine MRI at their local institution. A three dimensional (3D) digital image of the tumor in the breast was derived from supine MRI images and used to generate 1) an interactive 3D virtual image of the tumor in the breast (Visualizer) and 2) a plastic bra-like form that allowed the surgeon to place a central wire and bracketing wires in the breast (BCL). The primary objective was to determine the proportion of patients who had the central localization wire deployed within the cancer on specimen mammogram. RESULTS: Fourteen patients were enrolled at 4 different sites by 6 surgeons. BCLs were successfully manufactured for all patients. The central wire was deployed within the tumor on specimen mammogram in 12 of the 13 patients who had a central wire placed (92%). The cancer was excised with negative margins in 14/14 cases (100%). No adverse events occurred. CONCLUSIONS: Supine MRI image acquisition was accomplished successfully across multiple sites. Multiple surgeons utilized the BCL system to localize cancers accurately and safely.


Asunto(s)
Neoplasias de la Mama , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Mamografía , Mastectomía Segmentaria/métodos , Plásticos
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