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1.
Haematologica ; 2024 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-38841800

RESUMEN

Diffuse large B-cell lymphoma (DLBCL) is the most common malignancy that develops in patients with ataxia-telangiectasia, a cancer-predisposing inherited syndrome characterized by inactivating germline ATM mutations. ATM is also frequently mutated in sporadic DLBCL. To investigate lymphomagenic mechanisms and lymphoma-specific dependencies underlying defective ATM, we applied ribonucleic acid (RNA)-seq and genome-scale loss-offunction clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 screens to systematically interrogate B-cell lymphomas arising in a novel murine model (Atm-/-nu-/-) with constitutional Atm loss, thymic aplasia but residual T-cell populations. Atm-/-nu-/-lymphomas, which phenotypically resemble either activated B-cell-like or germinal center Bcell-like DLBCL, harbor a complex karyotype, and are characterized by MYC pathway activation. In Atm-/-nu-/-lymphomas, we discovered nucleotide biosynthesis as a MYCdependent cellular vulnerability that can be targeted through the synergistic nucleotidedepleting actions of mycophenolate mofetil (MMF) and the WEE1 inhibitor, adavosertib (AZD1775). The latter is mediated through a synthetically lethal interaction between RRM2 suppression and MYC dysregulation that results in replication stress overload in Atm-/-nu-/-lymphoma cells. Validation in cell line models of human DLBCL confirmed the broad applicability of nucleotide depletion as a therapeutic strategy for MYC-driven DLBCL independent of ATM mutation status. Our findings extend current understanding of lymphomagenic mechanisms underpinning ATM loss and highlight nucleotide metabolism as a targetable therapeutic vulnerability in MYC-driven DLBCL.

2.
Cancer Cell ; 42(5): 850-868.e9, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38670091

RESUMEN

TP53-mutant blood cancers remain a clinical challenge. BH3-mimetic drugs inhibit BCL-2 pro-survival proteins, inducing cancer cell apoptosis. Despite acting downstream of p53, functional p53 is required for maximal cancer cell killing by BH3-mimetics through an unknown mechanism. Here, we report p53 is activated following BH3-mimetic induced mitochondrial outer membrane permeabilization, leading to BH3-only protein induction and thereby potentiating the pro-apoptotic signal. TP53-deficient lymphomas lack this feedforward loop, providing opportunities for survival and disease relapse after BH3-mimetic treatment. The therapeutic barrier imposed by defects in TP53 can be overcome by direct activation of the cGAS/STING pathway, which promotes apoptosis of blood cancer cells through p53-independent BH3-only protein upregulation. Combining clinically relevant STING agonists with BH3-mimetic drugs efficiently kills TRP53/TP53-mutant mouse B lymphoma, human NK/T lymphoma, and acute myeloid leukemia cells. This represents a promising therapy regime that can be fast-tracked to tackle TP53-mutant blood cancers in the clinic.


Asunto(s)
Apoptosis , Proteínas de la Membrana , Proteína p53 Supresora de Tumor , Proteína p53 Supresora de Tumor/genética , Humanos , Animales , Ratones , Proteínas de la Membrana/genética , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Mutación , Neoplasias Hematológicas/tratamiento farmacológico , Neoplasias Hematológicas/genética , Proteínas Proto-Oncogénicas c-bcl-2/genética , Fragmentos de Péptidos/farmacología , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Transducción de Señal/efectos de los fármacos , Proteínas Proto-Oncogénicas/genética
3.
Cancer Discov ; 14(2): 362-379, 2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-37877779

RESUMEN

Mutations in the tumor suppressor TP53 cause cancer and impart poor chemotherapeutic responses, reportedly through loss-of-function, dominant-negative effects and gain-of-function (GOF) activities. The relative contributions of these attributes is unknown. We found that removal of 12 different TP53 mutants with reported GOFs by CRISPR/Cas9 did not impact proliferation and response to chemotherapeutics of 15 human cancer cell lines and colon cancer-derived organoids in culture. Moreover, removal of mutant TP53/TRP53 did not impair growth or metastasis of human cancers in immune-deficient mice or growth of murine cancers in immune-competent mice. DepMap mining revealed that removal of 158 different TP53 mutants had no impact on the growth of 391 human cancer cell lines. In contrast, CRISPR-mediated restoration of wild-type TP53 extinguished the growth of human cancer cells in vitro. These findings demonstrate that LOF but not GOF effects of mutant TP53/TRP53 are critical to sustain expansion of many tumor types. SIGNIFICANCE: This study provides evidence that removal of mutant TP53, thereby deleting its reported GOF activities, does not impact the survival, proliferation, metastasis, or chemotherapy responses of cancer cells. Thus, approaches that abrogate expression of mutant TP53 or target its reported GOF activities are unlikely to exert therapeutic impact in cancer. See related commentary by Lane, p. 211 . This article is featured in Selected Articles from This Issue, p. 201.


Asunto(s)
Neoplasias del Colon , Proteína p53 Supresora de Tumor , Humanos , Ratones , Animales , Línea Celular Tumoral , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Mutación , Neoplasias del Colon/genética , Proliferación Celular
5.
Cell Death Differ ; 31(2): 150-158, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38097622

RESUMEN

Whole-genome screens using CRISPR technologies are powerful tools to identify novel tumour suppressors as well as factors that impact responses of malignant cells to anti-cancer agents. Applying this methodology to lymphoma cells, we conducted a genome-wide screen to identify novel inhibitors of tumour expansion that are induced by the tumour suppressor TRP53. We discovered that the absence of Arrestin domain containing 3 (ARRDC3) increases the survival and long-term competitiveness of MYC-driven lymphoma cells when treated with anti-cancer agents that activate TRP53. Deleting Arrdc3 in mice caused perinatal lethality due to various developmental abnormalities, including cardiac defects. Notably, the absence of ARRDC3 markedly accelerated MYC-driven lymphoma development. Thus, ARRDC3 is a new mediator of TRP53-mediated suppression of tumour expansion, and this discovery may open new avenues to harness this process for cancer therapy.


Asunto(s)
Linfoma , Neoplasias , Animales , Ratones , Arrestinas/genética , Arrestinas/metabolismo , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Neoplasias/genética
6.
Acta Derm Venereol ; 103: adv9400, 2023 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-37787418

RESUMEN

Type 2 diabetes is associated with an increased risk of herpes zoster and postherpetic neuralgia. However, the association of type 1 diabetes with herpes zoster or postherpetic neuralgia remains unclear. This retrospective cohort study using Taiwan's Health Insurance Research Database included 199,566 patients with type 1 diabetes and 1,458,331 with type 2 diabetes, identified during the period 2000 to 2012. Patients with type 1 diabetes had a significantly higher risk of developing herpes zoster than those with type 2 diabetes (p < 0.001). Across all age groups, the impact of diabetes on herpes zoster was greater in type 1 than in type 2 diabetes. Patients with both type 1 and type 2 diabetes had a 1.45-fold higher risk of post-herpetic neuralgia than those without diabetes (hazard ratio 1.45, 95% confidence interval 1.28-1.65; hazard ratio 1.45, 95% confidence interval 1.37-1.52, respectively), and there was no difference between the 2 types of diabetes (hazard ratio 1.06; 95% confidence interval 0.93-1.21). The results recommend consideration of herpes zoster vaccination at an earlier age in patients with type 1 diabetes.


Asunto(s)
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Herpes Zóster , Neuralgia Posherpética , Humanos , Neuralgia Posherpética/diagnóstico , Neuralgia Posherpética/epidemiología , Neuralgia Posherpética/complicaciones , Estudios de Cohortes , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiología , Estudios Retrospectivos , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/epidemiología , Herpes Zóster/epidemiología , Herpesvirus Humano 3
7.
WMJ ; 122(4): 262-267, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37768766

RESUMEN

BACKGROUND: Primary care physicians are often the first to identify signs and symptoms concerning for cancer. An important aspect of cancer screening is thorough skin examinations and subsequent referral to a dermatologist for atypical cutaneous presentations, which may be associated with an underlying visceral malignancy. Diagnostic considerations for pruritus without dermatitis ("itch without rash") in adults include senile pruritus, medication reaction, and paraneoplastic syndrome. Recognition of cutaneous manifestations of cancer should prompt cancer screening by primary care providers. OBJECTIVE: To update practicing physicians on current cancer screening guidelines with a specific focus on cutaneous clues to prompt further workup. METHODS: American Cancer Society and United States Preventive Services Task Force guidelines were systematically reviewed using PubMed and organizational websites during August and September, 2021, with review of Task Force Guidelines during October, 2022. RESULTS: Colorectal, cervical, breast, lung, skin, prostate, ovarian, hematologic, pancreatic, thyroid, testicular, bladder, oral, and gastric cancer screening guidelines are summarized. CONCLUSIONS: Primary care physicians can recognize atypical cutaneous conditions and facilitate referral to a dermatologist for evaluation and/or directly order tests themselves to initiate appropriate cancer screening.

8.
Children (Basel) ; 10(9)2023 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-37761501

RESUMEN

Suctioning of newborns immediately after birth, as part of delivery room resuscitation, is only recommended if the airway is obstructed. The aim of this study was to describe the use of suctioning during newborn resuscitation among survivors versus those who died within 3 days and potential suction-related heart rate responses and associations to newborn characteristics. This was a retrospective observational study from July 2013 to July 2016 in a referral hospital in rural Tanzania. Research assistants observed and documented all deliveries, newborn resuscitations were video-recorded, and newborn heart rates were captured with a dry-electrode electrocardiogram. Liveborn infants ≥34 weeks gestation who received ventilation and with complete datasets were eligible. All 30 newborns who died were included, and a total of 46 survivors were selected as controls. Videos were annotated and heart rate patterns were observed before and after the suction events. Suctioning was performed more frequently than recommended. No differences were found in suctioning characteristics between newborns who died versus those who survived. In 13% of suction events, a significant heart rate change (i.e., arrhythmia or brief/sustained >15% fall in heart rate) was observed in relation to suctioning. This represents a potential additional harm to already depressed newborns undergoing resuscitation.

9.
Semin Perinatol ; 47(7): 151824, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37748941

RESUMEN

Blended learning is a learner-centered educational method that combines online and traditional face-to-face educational strategies. Simulation is a commonly utilized platform for experiential learning and an ideal component of a blended learning curriculum. This section describes blended learning, including its strengths and limitations, educational frameworks, uses within health professions education, best practices, and challenges. Also included is a brief introduction to simulation-based education, along with theoretical and real-world examples of how simulation may be integrated into a blended learning curriculum. Examples of blended learning in Neonatal-Perinatal Medicine, specifically within the Neonatal Resuscitation Program, procedural skills training, and the National Neonatology Curriculum, are reviewed.


Asunto(s)
Neonatología , Humanos , Recién Nacido , Resucitación , Curriculum , Aprendizaje , Aprendizaje Basado en Problemas
10.
Oncogene ; 42(37): 2776-2781, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37567974

RESUMEN

The BH3-mimetic drug Venetoclax, a specific inhibitor of anti-apoptotic BCL-2, has had clinical success for the treatment of chronic lymphocytic leukaemia and acute myeloid leukaemia. Attention has now shifted towards related pro-survival BCL-2 family members, hypothesising that new BH3-mimetic drugs targeting these proteins may emulate the success of Venetoclax. BH3-mimetics targeting pro-survival MCL-1 or BCL-XL have entered clinical trials, but managing on-target toxicities is challenging. While increasing evidence suggests BFL-1/A1 is a resistance factor for diverse chemotherapeutic agents and BH3-mimetic drugs in haematological malignancies, few studies have explored the role of BCL-W in the development, expansion, and therapeutic responses of cancer. Previously, we found that BCL-W was not required for the ongoing survival and growth of various established human Burkitt lymphoma and diffuse large B cell lymphoma cell lines. However, questions remained about whether BCL-W impacts lymphoma development. Here, we show that BCL-W appears dispensable for MYC-driven lymphomagenesis, and such tumours arising in the absence of BCL-W show no compensatory changes to BCL-2 family member expression, nor altered sensitivity to BH3-mimetic drugs. These results demonstrate that BCL-W does not play a major role in the development of MYC-driven lymphoma or the responses of these tumours to anti-cancer agents.


Asunto(s)
Antineoplásicos , Linfoma de Burkitt , Linfoma de Células B Grandes Difuso , Humanos , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Apoptosis , Linfoma de Burkitt/tratamiento farmacológico , Linfoma de Burkitt/genética , Linfoma de Burkitt/patología , Línea Celular Tumoral , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Linfoma de Células B Grandes Difuso/genética , Linfoma de Células B Grandes Difuso/metabolismo , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/genética , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo
11.
Int J Mol Sci ; 24(13)2023 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-37446191

RESUMEN

Cholesterol is essential for cellular function and is stored as cholesteryl esters (CEs). CEs biosynthesis is catalyzed by the enzymes acyl-CoA:cholesterol acyltransferase 1 and 2 (ACAT1 and ACAT2), with ACAT1 being the primary isoenzyme in most cells in humans. In Alzheimer's Disease, CEs accumulate in vulnerable brain regions. Therefore, ACATs may be promising targets for treating AD. F12511 is a high-affinity ACAT1 inhibitor that has passed phase 1 safety tests for antiatherosclerosis. Previously, we developed a nanoparticle system to encapsulate a large concentration of F12511 into a stealth liposome (DSPE-PEG2000 with phosphatidylcholine). Here, we injected the nanoparticle encapsulated F12511 (nanoparticle F) intravenously (IV) in wild-type mice and performed an HPLC/MS/MS analysis and ACAT enzyme activity measurement. The results demonstrated that F12511 was present within the mouse brain after a single IV but did not overaccumulate in the brain or other tissues after repeated IVs. A histological examination showed that F12511 did not cause overt neurological or systemic toxicity. We then showed that a 2-week IV delivery of nanoparticle F to aging 3xTg AD mice ameliorated amyloidopathy, reduced hyperphosphorylated tau and nonphosphorylated tau, and reduced neuroinflammation. This work lays the foundation for nanoparticle F to be used as a possible therapy for AD and other neurodegenerative diseases.


Asunto(s)
Enfermedad de Alzheimer , Humanos , Ratones , Animales , Ratones Transgénicos , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/patología , Liposomas , Distribución Tisular , Espectrometría de Masas en Tándem , Acetil-CoA C-Acetiltransferasa/metabolismo
12.
Artículo en Inglés | MEDLINE | ID: mdl-37465092

RESUMEN

The blood oxygen level dependent (BOLD) signal from functional magnetic resonance imaging (fMRI) is a noninvasive technique that has been widely used in research to study brain function. However, fMRI suffers from susceptibility-induced off resonance fields which may cause geometric distortions and mismatches with anatomical images. State-of-the-art correction methods require acquiring reverse phase encoded images or additional field maps to enable distortion correction. However, not all imaging protocols include these additional scans and thus cannot take advantage of these susceptibility correction capabilities. As such, in this study we aim to enable state-of-the-art distortion correction with FSL's topup algorithm of historical and/or limited fMRI data that include only a structural image and single phase encoded fMRI. To do this, we use 3D U-net models to synthesize undistorted fMRI BOLD contrast images from the structural image and use this undistorted synthetic image as an anatomical target for distortion correction with topup. We evaluate the efficacy of this approach, named SynBOLD-DisCo (synthetic BOLD images for distortion correction), and show that BOLD images corrected using our approach are geometrically more similar to structural images than the distorted BOLD data and are practically equivalent to state-of-the-art correction methods which require reverse phase encoded data. Future directions include additional validation studies, integration with other preprocessing operations, retraining with broader pathologies, and investigating the effects of spin echo versus gradient echo images for training and distortion correction. In summary, we demonstrate SynBOLD-DisCo corrects distortion of fMRI when reverse phase encoding scans or field maps are not available.

13.
J Surg Res ; 287: 168-175, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36933548

RESUMEN

INTRODUCTION: Enoxaparin is administered for venous thromboembolic (VTE) prophylaxis in bariatric surgery patients. There is concern whether body mass index (BMI)-based enoxaparin dosing consistently achieves prophylactic targets in patients with severe obesity. METHODS: This retrospective study included patients who underwent bariatric surgery at an academic medical center from Jan 2015-May 2021 and had an anti-Xa level drawn 2.5-6 h after ≥3 doses of BMI-based prophylactic enoxaparin. The primary outcome was the percentage of patients who achieved a target anti-Xa level. Secondary outcomes were prevalence of venous thromboembolic and bleeding events within 30 d post-operatively. RESULTS: Overall, 137 patients were included. Mean BMI was 59.1 ± 10.4 kg/m2, mean age was 43.9 ± 13.3 y and 110 patients (80.3%) were female. Target anti-Xa levels were achieved in 116 patients (84.7%); 14 (10.2%) were above target and 7 (5.1%) were below target. Patients with above target anti-Xa levels were significantly shorter in height than those within target range (167.1 versus 159.8 cm, P = 0.003). Five patients (3.6%) had a bleeding event; no thromboembolisms occurred. Anti-Xa levels correlated more strongly with enoxaparin dose per unit estimated blood volume (EBV) than dose per unit BMI (Rho = 0.54 versus Rho = 0.33). CONCLUSIONS: Target range anti-Xa levels were achieved in 85% of patients using BMI-based enoxaparin dosing. Patients with above target anti-Xa levels were significantly shorter by nearly 3 inches, suggesting an increased risk of overdosing enoxaparin in shorter, obese patients. An EBV-based dosing regimen may better account for patient height and is supported by a greater correlation with anti-Xa levels with dosing based on EBV than BMI.


Asunto(s)
Cirugía Bariátrica , Tromboembolia Venosa , Humanos , Femenino , Adulto , Persona de Mediana Edad , Masculino , Enoxaparina , Índice de Masa Corporal , Anticoagulantes/efectos adversos , Estudios Retrospectivos , Tromboembolia Venosa/etiología , Tromboembolia Venosa/prevención & control , Heparina de Bajo-Peso-Molecular/uso terapéutico , Hemorragia/inducido químicamente , Hemorragia/prevención & control , Cirugía Bariátrica/efectos adversos
14.
Int J Mol Sci ; 24(6)2023 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-36982602

RESUMEN

Cholesterol is a key component of all mammalian cell membranes. Disruptions in cholesterol metabolism have been observed in the context of various diseases, including neurodegenerative disorders such as Alzheimer's disease (AD). The genetic and pharmacological blockade of acyl-CoA:cholesterol acyltransferase 1/sterol O-acyltransferase 1 (ACAT1/SOAT1), a cholesterol storage enzyme found on the endoplasmic reticulum (ER) and enriched at the mitochondria-associated ER membrane (MAM), has been shown to reduce amyloid pathology and rescue cognitive deficits in mouse models of AD. Additionally, blocking ACAT1/SOAT1 activity stimulates autophagy and lysosomal biogenesis; however, the exact molecular connection between the ACAT1/SOAT1 blockade and these observed benefits remain unknown. Here, using biochemical fractionation techniques, we observe cholesterol accumulation at the MAM which leads to ACAT1/SOAT1 enrichment in this domain. MAM proteomics data suggests that ACAT1/SOAT1 inhibition strengthens the ER-mitochondria connection. Confocal and electron microscopy confirms that ACAT1/SOAT1 inhibition increases the number of ER-mitochondria contact sites and strengthens this connection by shortening the distance between these two organelles. This work demonstrates how directly manipulating local cholesterol levels at the MAM can alter inter-organellar contact sites and suggests that cholesterol buildup at the MAM is the impetus behind the therapeutic benefits of ACAT1/SOAT1 inhibition.


Asunto(s)
Enfermedad de Alzheimer , Colesterol , Animales , Ratones , Enfermedad de Alzheimer/metabolismo , Colesterol/metabolismo , Retículo Endoplásmico/metabolismo , Mamíferos/metabolismo , Mitocondrias/metabolismo , Esteroles/metabolismo , Acetil-CoA C-Aciltransferasa/metabolismo , Esterol O-Aciltransferasa/metabolismo
15.
Int J Mol Sci ; 24(6)2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36982689

RESUMEN

Cholesterol is stored as cholesteryl esters by the enzymes acyl-CoA:cholesterol acyltransferases/sterol O:acyltransferases (ACATs/SOATs). ACAT1 blockade (A1B) ameliorates the pro-inflammatory responses of macrophages to lipopolysaccharides (LPS) and cholesterol loading. However, the mediators involved in transmitting the effects of A1B in immune cells is unknown. Microglial Acat1/Soat1 expression is elevated in many neurodegenerative diseases and in acute neuroinflammation. We evaluated LPS-induced neuroinflammation experiments in control vs. myeloid-specific Acat1/Soat1 knockout mice. We also evaluated LPS-induced neuroinflammation in microglial N9 cells with and without pre-treatment with K-604, a selective ACAT1 inhibitor. Biochemical and microscopy assays were used to monitor the fate of Toll-Like Receptor 4 (TLR4), the receptor at the plasma membrane and the endosomal membrane that mediates pro-inflammatory signaling cascades. In the hippocampus and cortex, results revealed that Acat1/Soat1 inactivation in myeloid cell lineage markedly attenuated LPS-induced activation of pro-inflammatory response genes. Studies in microglial N9 cells showed that pre-incubation with K-604 significantly reduced the LPS-induced pro-inflammatory responses. Further studies showed that K-604 decreased the total TLR4 protein content by increasing TLR4 endocytosis, thus enhancing the trafficking of TLR4 to the lysosomes for degradation. We concluded that A1B alters the intracellular fate of TLR4 and suppresses its pro-inflammatory signaling cascade in response to LPS.


Asunto(s)
Lipopolisacáridos , Microglía , Animales , Ratones , Aciltransferasas/metabolismo , Colesterol/metabolismo , Lipopolisacáridos/toxicidad , Lipopolisacáridos/metabolismo , Ratones Noqueados , Microglía/metabolismo , Enfermedades Neuroinflamatorias , Receptor Toll-Like 4/metabolismo
16.
Cell Death Differ ; 30(4): 1033-1046, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36739334

RESUMEN

Mutant TP53 proteins are thought to drive the development and sustained expansion of cancers at least in part through the loss of the wild-type (wt) TP53 tumour suppressive functions. Therefore, compounds that can restore wt TP53 functions in mutant TP53 proteins are expected to inhibit the expansion of tumours expressing mutant TP53. APR-246 has been reported to exert such effects in malignant cells and is currently undergoing clinical trials in several cancer types. However, there is evidence that APR-246 may also kill malignant cells that do not express mutant TP53. To support the clinical development of APR-246 it is important to understand its mechanism(s) of action. By establishing isogenic background tumour cell lines with different TP53/TRP53 states, we found that APR-246 can kill malignant cells irrespective of their TP53/TRP53 status. Accordingly, RNAseq analysis revealed that treatment with APR-246 induces expression of the same gene set in Eµ-Myc mouse lymphoma cells of all four possible TRP53 states, wt, wt alongside mutant, knockout and knockout alongside mutant. We found that depending on the type of cancer cell and the concentration of APR-246 used, this compound can kill malignant cells through induction of various programmed cell death pathways, including apoptosis, necroptosis and ferroptosis. The sensitivity of non-transformed cells to APR-246 also depended on the cell type. These findings reveal that the clinical testing of APR-246 should not be limited to cancers expressing mutant TP53 but expanded to cancers that express wt TP53 or are TP53-deficient.


Asunto(s)
Genes p53 , Proteína p53 Supresora de Tumor , Animales , Ratones , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Apoptosis , Línea Celular Tumoral , Mutación
18.
Plast Reconstr Surg ; 150(5): 941e-949e, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-35993869

RESUMEN

BACKGROUND: Fat necrosis is a well-recognized complication following autologous fat grafting. The purpose of this study was to evaluate the incidence of fat necrosis after large-volume fat grafting and identify risk factors for fat necrosis. METHODS: A retrospective review was performed on 83 consecutive patients who underwent large-volume fat grafting (>100 cc) to the breast performed by the senior author (L.P.B.) between September of 2011 and May of 2016. Fat necrosis was defined as palpable nodules, or nodules seen on imaging. RESULTS: A total of 148 breasts underwent 170 autologous fat transplantations. Indications included the following: 72 reconstructions after surgical therapy and 98 cosmetic augmentations. Mean age was 48 years, median graft volume was 300 cc, and median length of follow-up 423 days. Overall incidence of necrosis was 32.9 percent, with 47.8 percent in previously irradiated patients. Increased incidence of necrosis was associated with increasing fat graft volumes (OR, 1.002; p = 0.032), increasing body mass index (OR, 1.13; p = 0.04), and simultaneous implant exchange with fat ( p = 0.003). Fat grafting volumes greater than 450 cc in a single breast were also associated with an increase in fat necrosis ( p = 0.04). Within a group of six patients who had bilateral fat grafting with unilateral radiation therapy, there was a significant increase in necrosis on the irradiated side ( p = 0.015). In a cohort of non-BRAVA patients, reconstruction (compared to augmentation) was associated with fat necrosis ( p = 0.039). CONCLUSIONS: Increased rates of fat necrosis were associated with volumes greater than 450 cc, patients undergoing concurrent implant exchange with fat grafting, and fat grafting after a history of lumpectomy or mastectomy without preexpansion. In addition, radiation therapy may be associated with a higher rate of complications. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.


Asunto(s)
Neoplasias de la Mama , Necrosis Grasa , Mamoplastia , Humanos , Persona de Mediana Edad , Femenino , Necrosis Grasa/epidemiología , Necrosis Grasa/etiología , Mamoplastia/efectos adversos , Mamoplastia/métodos , Mastectomía/efectos adversos , Neoplasias de la Mama/etiología , Tejido Adiposo/trasplante , Trasplante Autólogo/efectos adversos , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento
19.
J Psychiatr Pract ; 28(4): 310-318, 2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-35797687

RESUMEN

Benzodiazepine withdrawal is a widespread problem with potentially severe and deadly consequences. Currently, the only medications available for treating benzodiazepine withdrawal are short-acting and long-acting benzodiazepines. Identifying other drugs to help in treating benzodiazepine withdrawal is necessary. Gabapentin, an anxiolytic drug that is also used off-label to treat alcohol withdrawal, is a potential candidate for modulating benzodiazepine withdrawal. Using electronic records from a large inpatient psychiatric facility, a retrospective study of 172 patients presenting with benzodiazepine withdrawal was conducted to determine if the coincidental use of gabapentin for other medical conditions was associated with better outcomes of benzodiazepine withdrawal (N=57 gabapentin, N=115 no gabapentin). The primary outcomes were hospital length of stay and total amount of benzodiazepines given (lorazepam milligram equivalent). In this retrospective analysis of electronic medical record data, the patients experiencing benzodiazepine withdrawal who received gabapentin as an adjunct to the use of benzodiazepines were administered a smaller amount of benzodiazepines and had a shorter length of hospital stay relative to the comparison group who did not receive adjunctive gabapentin. These results suggest the potential use of gabapentin as an adjunct to the use of benzodiazepines for treating benzodiazepine withdrawal. The limitations of this study included a small sample size and variability in medication management strategies across the sample.


Asunto(s)
Alcoholismo , Síndrome de Abstinencia a Sustancias , Benzodiazepinas/efectos adversos , Gabapentina/uso terapéutico , Humanos , Estudios Retrospectivos , Síndrome de Abstinencia a Sustancias/tratamiento farmacológico
20.
Appl Microbiol Biotechnol ; 106(12): 4523-4537, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35713659

RESUMEN

Sequence-based screening has been widely applied in the discovery of novel microbial enzymes. However, majority of the sequences in the genomic databases were annotated using computational approaches and lacks experimental characterization. Hence, the success in obtaining the functional biocatalysts with improved characteristics requires an efficient screening method that considers a wide array of factors. Recombinant expression of microbial enzymes is often hampered by the undesirable formation of inclusion body. Here, we present a systematic in silico screening method to identify the proteins expressible in soluble form and with the desired biological properties. The screening approach was adopted in the recombinant expression of dimethyl sulfide (DMS) monooxygenase in Escherichia coli. DMS monooxygenase, a two-component enzyme consisting of DmoA and DmoB subunits, was used as a model protein. The success rate of producing soluble and active DmoA is 71% (5 out of 7 genes). Interestingly, the soluble recombinant DmoA enzymes exhibited the NADH:FMN oxidoreductase activity in the absence of DmoB (second subunit), and the cofactor FMN, suggesting that DmoA is also an oxidoreductase. DmoA originated from Janthinobacterium sp. AD80 showed the maximum NADH oxidation activity (maximum reaction rate: 6.6 µM/min; specific activity: 133 µM/min/mg). This novel finding may allow DmoA to be used as an oxidoreductase biocatalyst for various industrial applications. The in silico gene screening methodology established from this study can increase the success rate of producing soluble and functional enzymes while avoiding the laborious trial and error involved in the screening of a large pool of genes available. KEY POINTS: • A systematic gene screening method was demonstrated. • DmoA is also an oxidoreductase capable of oxidizing NADH and reducing FMN. • DmoA oxidizes NADH in the absence of external FMN.


Asunto(s)
Escherichia coli , Oxigenasas de Función Mixta , Escherichia coli/genética , Escherichia coli/metabolismo , Mononucleótido de Flavina/metabolismo , Oxigenasas de Función Mixta/metabolismo , NAD/metabolismo , Oxidorreductasas/genética , Oxidorreductasas/metabolismo , Sulfuros
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