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1.
Cell ; 187(8): 1971-1989.e16, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38521060

RESUMEN

Amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) share many clinical, pathological, and genetic features, but a detailed understanding of their associated transcriptional alterations across vulnerable cortical cell types is lacking. Here, we report a high-resolution, comparative single-cell molecular atlas of the human primary motor and dorsolateral prefrontal cortices and their transcriptional alterations in sporadic and familial ALS and FTLD. By integrating transcriptional and genetic information, we identify known and previously unidentified vulnerable populations in cortical layer 5 and show that ALS- and FTLD-implicated motor and spindle neurons possess a virtually indistinguishable molecular identity. We implicate potential disease mechanisms affecting these cell types as well as non-neuronal drivers of pathogenesis. Finally, we show that neuron loss in cortical layer 5 tracks more closely with transcriptional identity rather than cellular morphology and extends beyond previously reported vulnerable cell types.


Asunto(s)
Esclerosis Amiotrófica Lateral , Degeneración Lobar Frontotemporal , Corteza Prefrontal , Animales , Humanos , Ratones , Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/metabolismo , Esclerosis Amiotrófica Lateral/patología , Demencia Frontotemporal/genética , Degeneración Lobar Frontotemporal/genética , Degeneración Lobar Frontotemporal/metabolismo , Degeneración Lobar Frontotemporal/patología , Perfilación de la Expresión Génica , Neuronas/metabolismo , Corteza Prefrontal/metabolismo , Corteza Prefrontal/patología , Análisis de Expresión Génica de una Sola Célula
2.
J Biol Chem ; 299(1): 102784, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36502921

RESUMEN

Deinococcus radiodurans is known for its remarkable ability to withstand harsh stressful conditions. The outermost layer of its cell envelope is a proteinaceous coat, the S-layer, essential for resistance to and interactions with the environment. The S-layer Deinoxanthin-binding complex (SDBC), one of the main units of the characteristic multilayered cell envelope of this bacterium, protects against environmental stressors and allows exchanges with the environment. So far, specific regions of this complex, the collar and the stalk, remained unassigned. Here, these regions are resolved by cryo-EM and locally refined. The resulting 3D map shows that the collar region of this multiprotein complex is a trimer of the protein DR_0644, a Cu-only superoxide dismutase (SOD) identified here to be efficient in quenching reactive oxygen species. The same data also showed that the stalk region consists of a coiled coil that extends into the cell envelope for ∼280 Å, reaching the inner membrane. Finally, the orientation and localization of the complex are defined by in situ cryo-electron crystallography. The structural organization of the SDBC couples fundamental UV antenna properties with the presence of a Cu-only SOD, showing here coexisting photoprotective and chemoprotective functions. These features suggests how the SDBC and similar protein complexes, might have played a primary role as evolutive templates for the origin of photoautotrophic processes by combining primary protective needs with more independent energetic strategies.


Asunto(s)
Deinococcus , Proteínas Bacterianas/metabolismo , Membrana Celular/metabolismo , Deinococcus/química , Deinococcus/citología , Deinococcus/metabolismo , Estrés Oxidativo , Superóxido Dismutasa/metabolismo
3.
Curr Issues Mol Biol ; 46(5): 3990-4003, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38785514

RESUMEN

Retinoic acid (RA) regulates stemness and differentiation in human embryonic stem cells (ESCs). Ewing sarcoma (ES) is a pediatric tumor that may arise from the abnormal development of ESCs. Here we show that RA impairs the viability of SK-ES-1 ES cells and affects the cell cycle. Cells treated with RA showed increased levels of p21 and its encoding gene, CDKN1A. RA reduced mRNA and protein levels of SRY-box transcription factor 2 (SOX2) as well as mRNA levels of beta III Tubulin (TUBB3), whereas the levels of CD99 increased. Exposure to RA reduced the capability of SK-ES-1 to form tumorspheres with high expression of SOX2 and Nestin. Gene expression of CD99 and CDKN1A was reduced in ES tumors compared to non-tumoral tissue, whereas transcript levels of SOX2 were significantly higher in tumors. For NES and TUBB3, differences between tumors and control tissue did not reach statistical significance. Low expression of CD99 and NES, and high expression of SOX2, were significantly associated with a poorer patient prognosis indicated by shorter overall survival (OS). Our results indicate that RA may display rather complex modulatory effects on multiple target genes associated with the maintenance of stem cell's features versus their differentiation, cell cycle regulation, and patient prognosis in ES.

4.
Ann Oncol ; 35(7): 643-655, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38777726

RESUMEN

BACKGROUND: POLE and POLD1 proofreading deficiency (POLE/D1pd) define a rare subtype of ultramutated metastatic colorectal cancer (mCRC; over 100 mut/Mb). Disease-specific data about the activity and efficacy of immune checkpoint inhibitors (ICIs) in POLE/D1pd mCRC are lacking and it is unknown whether outcomes may be different from mismatch repair-deficient (dMMR)/microsatellite instability-high (MSI-H) mCRCs treated with ICIs. PATIENTS AND METHODS: In this global study, we collected 27 patients with mCRC harboring POLE/D1 mutations leading to proofreading deficiency and treated with anti-programmed cell death-ligand 1 alone +/- anti-cytotoxic T-lymphocyte antigen-4 agents. We collected clinicopathological and genomic characteristics, response, and survival outcomes after ICIs of POLE/D1pd mCRC and compared them with a cohort of 610 dMMR/MSI-H mCRC patients treated with ICIs. Further genomic analyses were carried out in an independent cohort of 7241 CRCs to define POLE and POLD1pd molecular profiles and mutational signatures. RESULTS: POLE/D1pd was associated with younger age, male sex, fewer RAS/BRAF driver mutations, and predominance of right-sided colon cancers. Patients with POLE/D1pd mCRC showed a significantly higher overall response rate (ORR) compared to dMMR/MSI-H mCRC (89% versus 54%; P = 0.01). After a median follow-up of 24.9 months (interquartile range: 11.3-43.0 months), patients with POLE/D1pd showed a significantly superior progression-free survival (PFS) compared to dMMR/MSI-H mCRC [hazard ratio (HR) = 0.24, 95% confidence interval (CI) 0.08-0.74, P = 0.01] and superior overall survival (OS) (HR = 0.38, 95% CI 0.12-1.18, P = 0.09). In multivariable analyses including the type of DNA repair defect, POLE/D1pd was associated with significantly improved PFS (HR = 0.17, 95% CI 0.04-0.69, P = 0.013) and OS (HR = 0.24, 95% CI 0.06-0.98, P = 0.047). Molecular profiling showed that POLE/D1pd tumors have higher tumor mutational burden (TMB). Responses were observed in both subtypes and were associated with the intensity of POLE/D1pd signature. CONCLUSIONS: Patients with POLE/D1pd mCRC showed more favorable outcomes compared to dMMR/MSI-H mCRC to treatment with ICIs in terms of tumor response and survival.


Asunto(s)
Neoplasias Colorrectales , ADN Polimerasa III , ADN Polimerasa II , Inhibidores de Puntos de Control Inmunológico , Mutación , Proteínas de Unión a Poli-ADP-Ribosa , Humanos , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Masculino , Femenino , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Persona de Mediana Edad , Anciano , ADN Polimerasa II/genética , Proteínas de Unión a Poli-ADP-Ribosa/genética , ADN Polimerasa III/genética , Adulto , Inestabilidad de Microsatélites , Anciano de 80 o más Años , Reparación de la Incompatibilidad de ADN
5.
An Acad Bras Cienc ; 96(2): e20230652, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38922275

RESUMEN

Trophic plasticity is a distinctive feature of freshwater fishes, representing an essential strategy for fish living in resource-variable environments. We analyzed the stomach contents of individuals sampled in two Atlantic Forest streams to identify the primary food sources consumed by Psalidodon aff. fasciatus and verify the existence of spatial, seasonal, and ontogenetic variations. The diet was determined by analyzing the stomach contents using the Volume Method to quantify the importance of food items. In general, Psalidodon aff. fasciatus was classified as an omnivorous species, consuming mainly insects, plant material, and filamentous algae. The results also showed significant effects for all factors considered (spatial, seasonal, and ontogenetic). Finally, Psalidodon aff. fasciatus demonstrated considerable trophic plasticity, which can result in better use of available resources in the environment and improved resource partitioning, reducing intraspecific and interspecific competition.


Asunto(s)
Characidae , Contenido Digestivo , Ríos , Estaciones del Año , Animales , Brasil , Characidae/fisiología , Characidae/clasificación , Conducta Alimentaria/fisiología , Bosques , Cadena Alimentaria
6.
Ann Oncol ; 34(11): 1025-1034, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37619846

RESUMEN

BACKGROUND: The prognostic value of KRAS and BRAFV600E mutations in stage III colon cancer (CC) remains controversial and has never been clearly analyzed in patients with microsatellite instability-high (MSI-H) tumors due to sample size limitations. Data are also lacking for KRAS submutations and prognosis. PATIENTS AND METHODS: We examined clinicopathological variables and prognosis in patients with surgically resected stage III CC who participated in seven clinical trials from the ACCENT/IDEA databases. Associations between KRAS exon 2 and BRAFV600E mutations and time to recurrence (TTR), overall survival (OS), and survival after recurrence (SAR) were assessed using a Cox model. We also analyzed the prognostic value of KRAS exon 2 submutations. RESULTS: Among 8460 patients, 11.4% had MSI-H status. In the MSI-H group, BRAFV600E, KRAS exon 2 mutants, and double-wild-type statuses were detected in 40.6%, 18.1%, and 41.3%, respectively, whereas and in the microsatellite stable (MSS) group, these were detected in 7.7%, 38.6%, and 53.8%, respectively. In the MSS group, 5-year TTR rates of 61.8%, 66.3%, and 72.9% were observed among patients with BRAFV600E, KRAS exon 2 mutants, and those who were DWT, respectively [adjusted hazard ratio (HR) = 1.58 and 1.31, both P < 0.001]. In the MSI-H group, 5-year TTR rates did not differ significantly among the mutated subgroups. Similar results were found for OS. However, survival after relapse was significantly shorter in the KRAS exon 2- and BRAFV600E-mutated patients in both MSS (adjusted HR = 2.06 and 1.15; both P < 0.05) and MSI-H (adjusted HR = 1.99 and 1.81; both P < 0.05) groups. In the MSS group, KRAS exon 2 mutations were associated with TTR, but only p.G12C, p.G12D, and p.G13D were associated with poor outcomes after disease recurrence. CONCLUSIONS: Testing for both KRAS and BRAFV600E mutations in stage III patients should be considered as they can better define individual patient prognosis, and may also enable patient selection for (neo)adjuvant trials dedicated to specific molecular subtypes with poor prognosis.


Asunto(s)
Neoplasias del Colon , Inestabilidad de Microsatélites , Proteínas Proto-Oncogénicas B-raf , Proteínas Proto-Oncogénicas p21(ras) , Pronóstico , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/genética , Ensayos Clínicos Controlados Aleatorios como Asunto , Humanos , Proteínas Proto-Oncogénicas p21(ras)/genética , Exones , Proteínas Proto-Oncogénicas B-raf/genética , Masculino , Femenino , Persona de Mediana Edad , Resultado del Tratamiento
7.
Ann Oncol ; 34(8): 703-713, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37269904

RESUMEN

BACKGROUND: Mismatch repair-deficient (dMMR) tumors displaying microsatellite instability (MSI) represent a paradigm for the success of immune checkpoint inhibitor (ICI)-based immunotherapy, particularly in patients with metastatic colorectal cancer (mCRC). However, a proportion of patients with dMMR/MSI mCRC exhibit resistance to ICI. Identification of tools predicting MSI mCRC patient response to ICI is required for the design of future strategies further improving this therapy. PATIENTS AND METHODS: We combined high-throughput DNA and RNA sequencing of tumors from 116 patients with MSI mCRC treated with anti-programmed cell death protein 1 ± anti-cytotoxic T-lymphocyte-associated protein 4 of the NIPICOL phase II trial (C1, NCT03350126, discovery set) and the ImmunoMSI prospective cohort (C2, validation set). The DNA/RNA predictors whose status was significantly associated with ICI status of response in C1 were subsequently validated in C2. Primary endpoint was progression-free survival by immune RECIST (iRECIST) (iPFS). RESULTS: Analyses showed no impact of previously suggested DNA/RNA indicators of resistance to ICI, e.g. MSIsensor score, tumor mutational burden, or specific cellular and molecular tumoral contingents. By contrast, iPFS under ICI was shown in C1 and C2 to depend both on a multiplex MSI signature involving the mutations of 19 microsatellites hazard ratio cohort C2 (HRC2) = 3.63; 95% confidence interval (CI) 1.65-7.99; P = 1.4 × 10-3] and the expression of a set of 182 RNA markers with a non-epithelial transforming growth factor beta (TGFB)-related desmoplastic orientation (HRC2 = 1.75; 95% CI 1.03-2.98; P = 0.035). Both DNA and RNA signatures were independently predictive of iPFS. CONCLUSIONS: iPFS in patients with MSI mCRC can be predicted by simply analyzing the mutational status of DNA microsatellite-containing genes in epithelial tumor cells together with non-epithelial TGFB-related desmoplastic RNA markers.


Asunto(s)
Neoplasias del Colon , Neoplasias Colorrectales , Neoplasias del Recto , Humanos , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Inestabilidad de Microsatélites , Estudios Prospectivos , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Reparación de la Incompatibilidad de ADN/genética
8.
PLoS Biol ; 18(8): e3000820, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32866173

RESUMEN

Mutations in the gene encoding the microtubule-severing protein spastin (spastic paraplegia 4 [SPG4]) cause hereditary spastic paraplegia (HSP), associated with neurodegeneration, spasticity, and motor impairment. Complicated forms (complicated HSP [cHSP]) further include cognitive deficits and dementia; however, the etiology and dysfunctional mechanisms of cHSP have remained unknown. Here, we report specific working and associative memory deficits upon spastin depletion in mice. Loss of spastin-mediated severing leads to reduced synapse numbers, accompanied by lower miniature excitatory postsynaptic current (mEPSC) frequencies. At the subcellular level, mutant neurons are characterized by longer microtubules with increased tubulin polyglutamylation levels. Notably, these conditions reduce kinesin-microtubule binding, impair the processivity of kinesin family protein (KIF) 5, and reduce the delivery of presynaptic vesicles and postsynaptic α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors. Rescue experiments confirm the specificity of these results by showing that wild-type spastin, but not the severing-deficient and disease-associated K388R mutant, normalizes the effects at the synaptic, microtubule, and transport levels. In addition, short hairpin RNA (shRNA)-mediated reduction of tubulin polyglutamylation on spastin knockout background normalizes KIF5 transport deficits and attenuates the loss of excitatory synapses. Our data provide a mechanism that connects spastin dysfunction with the regulation of kinesin-mediated cargo transport, synapse integrity, and cognition.


Asunto(s)
Ácido Glutámico/metabolismo , Cinesinas/metabolismo , Trastornos de la Memoria/metabolismo , Trastornos de la Memoria/fisiopatología , Memoria a Corto Plazo , Neuronas/metabolismo , Espastina/deficiencia , Tubulina (Proteína)/metabolismo , Potenciales de Acción , Animales , Membrana Celular/metabolismo , Espinas Dendríticas/metabolismo , Espinas Dendríticas/ultraestructura , Potenciales Postsinápticos Excitadores , Hipocampo/patología , Hipocampo/fisiopatología , Ratones Noqueados , Microtúbulos/metabolismo , Microtúbulos/ultraestructura , Actividad Motora , Neuronas/patología , Neuronas/ultraestructura , Transporte de Proteínas , Espastina/metabolismo , Sinapsis/metabolismo , Sinapsis/ultraestructura , Vesículas Sinápticas/metabolismo
9.
Exp Brain Res ; 241(4): 1173-1183, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36912948

RESUMEN

Impairments in several domains of cognitive functions are observed in people with Type 2 Diabetes Mellitus (T2DM), often accompanied by low Brain-derived neurotrophic factor (BDNF) concentrations. Although aerobic and resistance exercise enhances cognitive functions and raises BDNF concentrations in several populations, it remained uncertain in T2DM subjects. This study compared the effects of a single bout of aerobic (AER, 40 min of treadmill walk at 90-95% of the maximum walk speed) or resistance (RES, 3 × 10 repetitions in eight exercises at 70% of 10-RM) exercise on specific cognitive domain performance and plasma BDNF concentrations of physically active T2DM subjects. Eleven T2DM subjects (9 women/2 men; 63 ± 7 years) performed two counterbalanced trials on non-consecutive days. Stroop Color and Word (SCW) task [assessing the attention (congruent condition) and inhibitory control (incongruent condition)], Visual response time (assessing the response time), and blood collection (for plasma BDNF concentrations) were performed pre and post-exercise sessions. With distinct magnitude, both AER and RES improved the incongruent-SCW (d = - 0.26 vs. - 0.43 in AER and RES, respectively; p < 0.05), RT(best) (d = - 0.31 vs. - 0.52, p < 0.05), and RT(1-5) (d = - 0.64 vs. - 0.21, p < 0.05). The congruent-SCW and RT(6-10) were not statistically different. Plasma BDNF concentrations were elevated 11% in AER (d = 0.30) but decreased by 15% in RES (d = - 0.43). A single session of aerobic or resistance exercise similarly improved the inhibitory control and response time of physically active T2DM subjects. Nevertheless, aerobic and resistance exercise sessions induced an opposite clinical effect in plasma BDNF concentrations.


Asunto(s)
Diabetes Mellitus Tipo 2 , Entrenamiento de Fuerza , Masculino , Persona de Mediana Edad , Humanos , Femenino , Anciano , Diabetes Mellitus Tipo 2/terapia , Factor Neurotrófico Derivado del Encéfalo , Tiempo de Reacción , Ejercicio Físico/fisiología
10.
Dis Esophagus ; 36(10)2023 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-37039273

RESUMEN

Self-expanding metallic stents (SEMS) are considered the treatment of choice for the palliation of dysphagia and fistulas in inoperable esophageal neoplasms. However, the safety of SEMSs in patients who received or who will be submitted to radiotherapy (RT) is uncertain. The study aimed to evaluate the impact of RT on adverse events (AEs) in patients with esophageal cancer with SEMSs. This is a retrospective study conducted at a tertiary cancer hospital from 2009 to 2018. We collected information regarding RT, the histological type of the tumor, the model of SEMSs and AEs after stent placement. Three hundred twenty-three patients with malignant stenosis or fistula were treated with SEMSs. The predominant histological type was squamous cell carcinoma (79.6%). A total of 282 partially covered and 41 fully covered SEMSs were inserted. Of the 323 patients, 182 did not received RT, 118 received RT before SEMS placement and 23 after. Comparing the group that received RT before stent insertion with the group that did not, the first one presented a higher frequency of severe pain (9/118 7.6% vs. 3/182 1.6%; P = 0.02). The group treated with RT after stent placement had a higher risk of global AEs (13/23 56.5% vs. 63/182 34.6%; P = 0.019), ingrowth/overgrowth (6/23 26.1% vs. 21/182 11.5%; P = 0.045) and gastroesophageal reflux (2/23 8.7% vs. 2/182 1.1%; P = 0.034). Treatment with RT before stent placement in patients with inoperable esophageal neoplasm prolongs survival and is associated with an increased risk of severe chest pain. Treatment with RT of patients with an esophageal stent increases the frequency of minor, not life-threatening AEs.


Asunto(s)
Trastornos de Deglución , Neoplasias Esofágicas , Estenosis Esofágica , Stents Metálicos Autoexpandibles , Humanos , Estudios Retrospectivos , Resultado del Tratamiento , Stents/efectos adversos , Neoplasias Esofágicas/terapia , Neoplasias Esofágicas/complicaciones , Trastornos de Deglución/etiología , Trastornos de Deglución/terapia , Cuidados Paliativos , Stents Metálicos Autoexpandibles/efectos adversos , Estenosis Esofágica/terapia
11.
Sensors (Basel) ; 23(10)2023 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-37430841

RESUMEN

Microfluidic-based platforms have become a hallmark for chemical and biological assays, empowering micro- and nano-reaction vessels. The fusion of microfluidic technologies (digital microfluidics, continuous-flow microfluidics, and droplet microfluidics, just to name a few) presents great potential for overcoming the inherent limitations of each approach, while also elevating their respective strengths. This work exploits the combination of digital microfluidics (DMF) and droplet microfluidics (DrMF) on a single substrate, where DMF enables droplet mixing and further acts as a controlled liquid supplier for a high-throughput nano-liter droplet generator. Droplet generation is performed at a flow-focusing region, operating on dual pressure: negative pressure applied to the aqueous phase and positive pressure applied to the oil phase. We evaluate the droplets produced with our hybrid DMF-DrMF devices in terms of droplet volume, speed, and production frequency and further compare them with standalone DrMF devices. Both types of devices enable customizable droplet production (various volumes and circulation speeds), yet hybrid DMF-DrMF devices yield more controlled droplet production while achieving throughputs that are similar to standalone DrMF devices. These hybrid devices enable the production of up to four droplets per second, which reach a maximum circulation speed close to 1540 µm/s and volumes as low as 0.5 nL.


Asunto(s)
Microfluídica , Ácidos Nucleicos , Bioensayo , Dispositivos Laboratorio en un Chip , Tecnología
12.
Int J Mol Sci ; 24(20)2023 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-37894922

RESUMEN

Changes in epigenetic programming have been proposed as being key events in the initiation and progression of childhood cancers. HMT euchromatic histone lysine methyltransferase 2 (G9a, EHMT2), which is encoded by the G9a (Ehmt2) gene, as well as its related protein GLP, which is encoded by the GLP/Ehmt1 gene, participate in epigenetic regulation by contributing to a transcriptionally repressed chromatin state. G9a/GLP activation has been reported in several cancer types. Herein, we evaluated the role of G9a in two solid pediatric tumors: neuroblastoma (NB) and Ewing sarcoma (ES). Our results show that G9a/Ehmt2 and GLP/Ehmt1 expression is higher in tumors with poorer prognosis, including St4 International Neuroblastoma Staging System (INSS) stage, MYCN amplified NB, and metastatic ES. Importantly, higher G9a and GLP levels were associated with shorter patient overall survival (OS) in both NB and ES. Moreover, pharmacological inhibition of G9a/GLP reduced cell viability in NB and ES cells. These findings suggest that G9a and GLP are associated with more aggressive NB and ES tumors and should be further investigated as being epigenetic targets in pediatric solid cancers.


Asunto(s)
Neuroblastoma , Sarcoma de Ewing , Niño , Humanos , Supervivencia Celular/genética , Epigénesis Genética , Antígenos de Histocompatibilidad/genética , Antígenos de Histocompatibilidad/metabolismo , Histona Metiltransferasas/metabolismo , N-Metiltransferasa de Histona-Lisina/genética , N-Metiltransferasa de Histona-Lisina/metabolismo , Neuroblastoma/genética , Sarcoma de Ewing/genética
13.
Ann Oncol ; 33(6): 628-637, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35306156

RESUMEN

BACKGROUND: Histological characteristics at the invasive front may reflect tumor aggressiveness; specifically, tumor budding (Bd) is an emerging prognostic biomarker in colon cancer (CC). We explored further the significance of Bd for risk stratification by evaluating survival of stage III CC patients included in the IDEA-France phase III trial. PATIENTS AND METHODS: This post-hoc study was conducted on tissue slides from 1048 stage III CC patients. Bd was scored by central review by the Bd criteria of the 2016 International Tumor Budding Consensus Conference (ITBCC 2016) and classified as Bd1 (0-4 buds/0.785 mm2), Bd2 (5-9 buds), and Bd3 (≥10 buds) categories. Disease-free survival (DFS) and overall survival (OS) were analyzed by the log-rank test. Clinicopathological features and Immunoscore® were correlated with Bd. RESULTS: Overall, Bd1, Bd2, and Bd3 were observed in 39%, 28%, and 33% of CC, respectively. Bd2 and Bd3 were associated with vascular (P = 0.002) and perineural invasions (P = 0.0009). The 3-year DFS and the 5-year OS rates for Bd (1 versus 2-3) were 79.4% versus 67.2% (P = 0.001) and 89.2% versus 80.8% (P = 0.001), respectively. This was confirmed after adjustment for relevant clinicopathological features for DFS [hazard ratio (HR) 1.41, 95% confidence interval (CI) 1.12-1.77, P = 0.003] and OS (HR 1.65, 95% CI 1.22-2.22, P = 0.001). When combined with pTN stage and Immunoscore® subgroups, Bd significantly improved disease prognostication. CONCLUSIONS: Bd demonstrated its independent prognostic value for DFS and OS. Given these findings, Bd as per the ITBCC 2016 should be mandatory in every pathology report in stage III CC patients. Bd and Immunoscore® could play a complementary role in personalized health care in this setting.


Asunto(s)
Neoplasias del Colon , Neoplasias del Colon/patología , Supervivencia sin Enfermedad , Francia/epidemiología , Humanos , Estadificación de Neoplasias , Pronóstico , Modelos de Riesgos Proporcionales
14.
Ann Oncol ; 33(10): 1052-1060, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35764271

RESUMEN

BACKGROUND: In the phase II multicohort CheckMate 142 study, nivolumab plus low-dose (1 mg/kg) ipilimumab provided robust and durable clinical benefit with a manageable safety profile in previously treated patients with microsatellite instability-high/mismatch repair-deficient (MSI-H/dMMR) metastatic colorectal cancer (mCRC) at 13.4- and 25.4-month median follow-up (Overman MJ, Lonardi S, Wong KYM et al. Durable clinical benefit with nivolumab plus ipilimumab in DNA mismatch repair-deficient/microsatellite instability-high metastatic colorectal cancer. J Clin Oncol. 2018;36:773-779. Overman MJ, Lonardi S, Wong KYM, et al. Nivolumab plus low-dose ipilimumab in previously treated patients with microsatellite instability-high/mismatch repair deficient metastatic colorectal cancer: long-term follow-up. J Clin Oncol. 2019;37:635). Here, we present results from the 4-year follow-up of these patients. PATIENTS AND METHODS: Patients received nivolumab (3 mg/kg) plus low-dose (1 mg/kg) ipilimumab every 3 weeks (four doses) followed by nivolumab (3 mg/kg) every 2 weeks until disease progression. Primary endpoint was investigator-assessed objective response rate (ORR; as per RECIST version 1.1). RESULTS: A total of 119 patients were treated; 76% had ≥2 prior lines of therapy. Median follow-up was 50.9 months (range 46.9-62.7 months). Median duration of therapy was 24.9 months [95% confidence interval (CI) 15.8-33.2 months]. Investigator-assessed ORR increased from 55% (95% CI 45% to 64%) at 13.4 months to 65% (95% CI 55% to 73%) at 50.9 months with a disease control rate of 81% (95% CI 72% to 87%). The complete response rate increased from 3% at 13.4 months to 13% at 50.9 months. Partial responses were observed in 52% of patients; 21% had stable disease, and 12% had progressive disease. Median time to response was 2.8 months (range 1.1-37.1 months), and median duration of response was not reached (range 1.4+ to 58.0+ months). At data cut-off, 37 (48%) patients had ongoing responses. Median progression-free survival was not reached [95% CI 38.4 months-not estimable (NE)], and median overall survival was not reached (95% CI NE). Grade 3-4 treatment-related adverse events (TRAEs) were observed in 32% of patients; 13% of patients had any-grade TRAEs leading to discontinuation. CONCLUSIONS: The results confirm long-term benefit of nivolumab plus low-dose ipilimumab for previously treated patients with MSI-H/dMMR mCRC. The safety profile was manageable with no new safety signals.


Asunto(s)
Neoplasias del Colon , Neoplasias Colorrectales , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias del Colon/tratamiento farmacológico , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Reparación de la Incompatibilidad de ADN/genética , Estudios de Seguimiento , Humanos , Ipilimumab , Inestabilidad de Microsatélites , Nivolumab/uso terapéutico
15.
PLoS Comput Biol ; 17(6): e1008994, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34138845

RESUMEN

Effectively designing and evaluating public health responses to the ongoing COVID-19 pandemic requires accurate estimation of the prevalence of COVID-19 across the United States (US). Equipment shortages and varying testing capabilities have however hindered the usefulness of the official reported positive COVID-19 case counts. We introduce four complementary approaches to estimate the cumulative incidence of symptomatic COVID-19 in each state in the US as well as Puerto Rico and the District of Columbia, using a combination of excess influenza-like illness reports, COVID-19 test statistics, COVID-19 mortality reports, and a spatially structured epidemic model. Instead of relying on the estimate from a single data source or method that may be biased, we provide multiple estimates, each relying on different assumptions and data sources. Across our four approaches emerges the consistent conclusion that on April 4, 2020, the estimated case count was 5 to 50 times higher than the official positive test counts across the different states. Nationally, our estimates of COVID-19 symptomatic cases as of April 4 have a likely range of 2.3 to 4.8 million, with possibly as many as 7.6 million cases, up to 25 times greater than the cumulative confirmed cases of about 311,000. Extending our methods to May 16, 2020, we estimate that cumulative symptomatic incidence ranges from 4.9 to 10.1 million, as opposed to 1.5 million positive test counts. The proposed combination of approaches may prove useful in assessing the burden of COVID-19 during resurgences in the US and other countries with comparable surveillance systems.


Asunto(s)
COVID-19/epidemiología , Gripe Humana , Modelos Estadísticos , Vigilancia de la Población , SARS-CoV-2 , Humanos , Incidencia , Gripe Humana/diagnóstico , Gripe Humana/epidemiología , Gripe Humana/mortalidad , Pandemias , Estados Unidos , Virología
16.
An Acad Bras Cienc ; 94(suppl 3): e20211404, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36417610

RESUMEN

The number of isotopic studies on Quaternary megafauna has increased over the last decades, yet, there is no published data addressing the status of scientific production of this research field. The present study shows the results of a bibliometric research carried out in the Scopus database where the publishing trends within this scientific field was analyzed using the open source software tool SciMAT. We retrieved 278 papers published from 1980 to 2019 and observed that a significant increase in publishing has mainly occurred in the last decade analyzed here. We also identified some of the field´s most influential articles and journals; recognized that carbon, oxygen and nitrogen isotopes are the most used markers in these studies; and that the most cited taxa are representatives of Equidae, Bovidae and Proboscidae. Also, Paleoecology is the basic thematic area, whereas Climate and Paleoenvironmental Changes is the one with the greatest development potential. Our results clearly show that the isotopic study on Quaternary megafauna is still under development and that some subjects could be further explored, such as analyzing more taxa within Carnivora, Pilosa, Notoungulata, Cetartiodactyla and Perissodactyla as well as using other less frequent stable isotope markers, such as strontium, calcium and hydrogen.


Asunto(s)
Bibliometría , Publicaciones , Humanos , Bases de Datos Factuales
17.
An Acad Bras Cienc ; 94(suppl 2): e20211207, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35730898

RESUMEN

Three SAR-derived observations of dark surface patches along the Northeastern Brazilian coastline by the end of 2019 were misreported in the Brazilian media as oil spill-related. Unfortunately, these observations were misled by false positives or look-alikes. Therefore, this paper aims to technically evaluate these look-alike classes by analyzing image attributes found to be helpful to the identification of ocean targets, including oil spills, rain cells, biofilms, and low wind conditions. We use image augmentation to extend our dataset size and create the probability density function curves. The processing includes image segmentation, optimal attribute extraction, and classification with random forest classifiers. Our results contrast with the open-source oil spill detection system and patch classifier methodology called "RIOSS." Analysis of the feature probability density functions based on optimal attributes is promising since we could capture most of the false positive targets in the three SAR-reported images in 2019. The only exception was the biofilm slick observed on October 28th, where the RIOSS mistakenly classified this organic patch as a low wind region with oil spots. This pitfall is acceptable at this project stage since we had only five biogenic film samples to train the algorithm.


Asunto(s)
Contaminación por Petróleo , Contaminantes Químicos del Agua , Brasil , Monitoreo del Ambiente/métodos , Contaminación por Petróleo/análisis , Radar , Contaminantes Químicos del Agua/análisis , Viento
18.
Pestic Biochem Physiol ; 184: 105129, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35715067

RESUMEN

Callosobruchus maculatus is the main pest cowpea (Vigna unguiculata). Given its relevance as an insect pest, studies have focused in finding toxic compounds which could prevent its predatory action towards the seeds. Clitoria fairchildiana is a native Amazon species, whose seeds are refractory to insect predation. This characteristic was the basis of our interest in evaluating the toxicity of its seed proteins to C. maculatus larvae. Seed proteins were fractioned, according to their solubility, to albumins (F1), globulins (F2), kaphyrins (F3), glutelins (F4), linked kaphyrins (F5) and cross-linked glutelins (F6). The fractionated proteins were quantified, analysed by tricine-SDS-PAGE and inserted into the diet of this insect pest in order to evaluate their insecticidal potential. The most toxic fraction to C. maculatus, the propanol soluble F3, was submitted to molecular exclusion chromatography and all of the peaks obtained, F3P1, F3P2, F3P3, caused a reduction of larval mass, especially F3P1, seen as a major ~12 kDa electrophoretic band. This protein was identified as a vicilin-like protein by mass spectrometry and BLAST analysis. The alignment of the Cfvic (C. fairchildiana vicilin) peptides with a V. unguiculata vicilin sequence, revealed that Cfvic has at least five peptides (ALLTLVNPDGR, AILTLVNPDGR, NFLAGGKDNV, ISDINSAMDR, NFLAGEK) which lined up with two chitin binding sites (ChBS). This finding was corroborated by chitin affinity chromatography and molecular docking of chitin-binding domains for N-Acetyl-D-glucosamine and by the reduction of Cfvic chitin affinity after chemical modification of its Lys residues. In conclusion, Cfvic is a 12 kDa vicilin-like protein, highly toxic to C. maculatus, acting as an insect toxin through its ability to bind to chitin structures present in the insect midgut.


Asunto(s)
Clitoria , Escarabajos , Animales , Quitina/metabolismo , Clitoria/metabolismo , Escarabajos/metabolismo , Cotiledón/metabolismo , Glútenes/análisis , Glútenes/metabolismo , Larva/metabolismo , Simulación del Acoplamiento Molecular , Proteínas de Almacenamiento de Semillas , Semillas/química
19.
Pestic Biochem Physiol ; 183: 105082, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35430072

RESUMEN

Schinus terebinthifolius, Raddi, has been extensively studied due to its anti-inflammatory and antibiotic properties. S. terebinthifolius was also toxic to some insects, however little has been explored about the nature of its insecticide compounds or the toxicity of this plant to insect species. In this work, we investigate the toxicity of S. terebinthifolius seed flour against the insect C. maculatus. S. terebinthifolius seed flour interfered with the post hatch development of the C. maculatus larvae, decreasing larval survival, mass and length. Using DEAE-cellulose chromatography, five protein fractions were isolated, a non-retained fraction (NRF) and four retained fractions, eluted with 0.25, 0.5, 0.7 and 1.0 M NaCl. Proteins with varying molecular masses were observed in all fractions. The majority protein bands were identified by mass spectrometry analysis and among the main identified proteins are 11S globulins (such glycinin), lipoxygenase, chitinases, 7S globulins (vicilins, canavalin and ß conglycinin), annexin, catalase and sucrose binding protein. All DEAE-protein fractions were toxic to the insect, interfering with the post hatch larval development and survival. Decreases greater than 90% were observed in the larval mass and length at 20 days after oviposition (DAO) for larvae raised on diet containing 0.5% of some fractions. Alterations in the level of proteins, glucose and in the activity of the enzymes lipases and cysteine proteases were also detected in these larvae. Our results show that seeds of S. terebinthifolius have an arsenal of toxic proteins with potential for the control of the insect C. maculatus.


Asunto(s)
Anacardiaceae , Escarabajos , Vigna , Gorgojos , Animales , Femenino , Harina , Larva , Semillas/química , Gorgojos/metabolismo
20.
Int J Mol Sci ; 23(19)2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-36232374

RESUMEN

Proteolysis-targeting chimeras (PROTACs) are molecules that selectively degrade a protein of interest (POI). The incorporation of ligands that recruit mouse double minute 2 (MDM2) into PROTACs, forming the so-called MDM2-based PROTACs, has shown promise in cancer treatment due to its dual mechanism of action: a PROTAC that recruits MDM2 prevents its binding to p53, resulting not only in the degradation of POI but also in the increase of intracellular levels of the p53 suppressor, with the activation of a whole set of biological processes, such as cell cycle arrest or apoptosis. In addition, these PROTACs, in certain cases, allow for the degradation of the target, with nanomolar potency, in a rapid and sustained manner over time, with less susceptibility to the development of resistance and tolerance, without causing changes in protein expression, and with selectivity to the target, including the respective isoforms or mutations, and to the cell type, overcoming some limitations associated with the use of inhibitors for the same therapeutic target. Therefore, the aim of this review is to analyze and discuss the characteristics of MDM2-based PROTACs developed for the degradation of oncogenic proteins and to understand what potential they have as future anticancer drugs.


Asunto(s)
Antineoplásicos , Neoplasias , Proteínas Proto-Oncogénicas c-mdm2 , Animales , Ratones , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Proteolisis , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo
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