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1.
Anal Chem ; 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39007441

RESUMEN

G-quadruplex structures within the nuclear genome (nG4) is an important regulatory factor, while the function of G4 in the mitochondrial genome (mtG4) still needs to be explored, especially in human sperms. To gain a better understanding of the relationship between mtG4 and mitochondrial function, it is crucial to develop excellent probes that can selectively visualize and track mtG4 in both somatic cells and sperms. Herein, based on our previous research on purine frameworks, we attempted for the first time to extend the conjugated structure from the C-8 site of purine skeleton and discovered that the purine derivative modified by the C-8 aldehyde group is an ideal platform for constructing near-infrared probes with extremely large Stokes shift (>220 nm). Compared with the compound substituted with methylpyridine (PAP), the molecule substituted with methylthiazole orange (PATO) showed better G4 recognition ability, including longer emission (∼720 nm), more significant fluorescent enhancement (∼67-fold), lower background, and excellent photostability. PATO exhibited a sensitive response to mtG4 variation in both somatic cells and human sperms. Most importantly, PATO helped us to discover that mtG4 was significantly increased in cells with mitochondrial respiratory chain damage caused by complex I inhibitors (6-OHDA and rotenone), as well as in human sperms that suffer from oxidative stress. Altogether, our study not only provides a novel ideal molecular platform for constructing high-performance probes but also develops an effective tool for studying the relationship between mtG4 and mitochondrial function in both somatic cells and human sperms.

2.
Ann Hematol ; 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38472362

RESUMEN

Multiple myeloma (MM) stands as the second most prevalent hematological malignancy, constituting approximately 10% of all hematological malignancies. Current guidelines recommend upfront autologous stem cell transplantation (ASCT) for transplant-eligible MM patients. This study seeks to delineate factors influencing post-ASCT outcomes in MM patients. Our cohort comprised 150 MM patients from Taipei Veterans General Hospital, with progression-free survival (PFS) as the primary endpoint and overall survival (OS) as the secondary endpoint. A Cox proportional hazards model was employed to discern potential predictive factors for survival. ASCT age ≥ 65 (hazard ratio [HR] 1.94, 95% confidence interval [CI] 1.08-3.47) and the presence of extramedullary disease (HR 2.53, 95% CI 1.53-4.19) negatively impacted PFS. Conversely, treatment response ≥ VGPR before ASCT (HR 0.52, 95% CI 0.31-0.87) and total CD34+ cells collected ≥ 4 × 106 cells/kg on the first stem cell harvesting (HR 0.52, 95% CI 0.32-0.87) were positively associated with PFS. For OS, patients with ISS stage III (HR 2.06, 95% CI 1.05-4.04), the presence of extramedullary disease (HR 3.92, 95% CI 2.03-7.58), light chain ratio ≥ 100 before ASCT (HR 7.08, 95% CI 1.45-34.59), post-ASCT cytomegalovirus infection (HR 9.43, 95% CI 3.09-28.84), and a lower conditioning melphalan dose (< 140 mg/m2; HR 2.75, 95% CI 1.23-6.17) experienced shorter OS. In contrast, post-ASCT day + 15 absolute monocyte counts (D15 AMC) > 500/µl (HR 0.36, 95% CI 0.17-0.79) and post-ASCT day + 15 platelet counts (D15 PLT) > 80,000/µl (HR 0.48, 95% CI 0.24-0.94) were correlated with improved OS. Significantly, early PLT and AMC recovery on day + 15 predicting longer OS represents a novel finding not previously reported. Other factors also align with previous studies. Our study provides real-world insights for post-ASCT outcome prediction beyond clinical trials.

3.
Exp Hematol Oncol ; 12(1): 35, 2023 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-37029450

RESUMEN

INTRODUCTION: Circulating monocytic myeloid-derived suppressive cells (M-MDSCs) are implicated as a poor prognostic factor and cause CAR T-cell failure in diffuse large B-cell lymphoma (DLBCL). Triggering receptors expressed on myeloid cells 2 (TREM2) are a transmembrane glycoprotein that polarize macrophages to anti-inflammation phenotype but have never been explored on M-MDSCs. This study aims to elucidate the expression and clinical impact of surface TREM2 on circulating M-MDSCs derived from DLBCL adults. METHODS: This prospective, observational study enrolled 100 adults with newly diagnosed and treatment-naïve DLBCL from May 2019 to October 2021. Human circulating M-MDSCs were obtained from freshly isolated peripheral blood, and each patient's surface-TREM2 level on M-MDSCs was normalized via a healthy control at the same performance of flow-cytometry analysis. Murine MDSCs derived from bone marrow (BM-MDSCs) were adopted to assess the link between Trem2 and cytotoxic T lymphocytes. RESULTS: More circulating M-MDSCs at diagnosis of DLBCL predicted worse progression-free (PFS) and overall survival (OS). Patients with higher IPI scores, bone marrow involvement, or lower absolute counts of CD4+ or CD8+ T cells in PB had significantly higher normalized TREM2 levels on M-MDSCs. Additionally, normalized TREM2 levels on M-MDSCs could be grouped into low (< 2%), medium (2-44%), or high (> 44%) levels, and a high normalized TREM2 level on M-MDSCs was proven as an independent prognostic factor for both PFS and OS via multivariate Cox regression analysis and associated with worst PFS and OS. Interestingly, normalized levels of surface TREM2 on M-MDSCs were negatively associated with absolute counts of PB CD8+ T cells and positively correlated with levels of intracellular arginase 1 (ARG1) within M-MDSCs. Wild-type BM-MDSCs had significantly higher mRNA levels of Arg1 and showed more prominent ability to suppress the proliferation of co-cultured CD8+ T cells than BM-MDSCs from Trem2 knockout mice, and the suppressive ability could be impaired by adding Arg1 inhibitors (CB1158) or supplementing L-arginine. CONCLUSION: In treatment-naïve DLBCL adults, a high surface-TREM2 level on circulating M-MDSCs is a poor prognostic factor for both PFS and OS and warrants further investigation for its potential as a novel target in immunotherapy.

4.
Nature ; 617(7959): 200-207, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37020024

RESUMEN

In all species, ribosomes synthesize proteins by faithfully decoding messenger RNA (mRNA) nucleotide sequences using aminoacyl-tRNA substrates. Current knowledge of the decoding mechanism derives principally from studies on bacterial systems1. Although key features are conserved across evolution2, eukaryotes achieve higher-fidelity mRNA decoding than bacteria3. In human, changes in decoding fidelity are linked to ageing and disease and represent a potential point of therapeutic intervention in both viral and cancer treatment4-6. Here we combine single-molecule imaging and cryogenic electron microscopy methods to examine the molecular basis of human ribosome fidelity to reveal that the decoding mechanism is both kinetically and structurally distinct from that of bacteria. Although decoding is globally analogous in both species, the reaction coordinate of aminoacyl-tRNA movement is altered on the human ribosome and the process is an order of magnitude slower. These distinctions arise from eukaryote-specific structural elements in the human ribosome and in the elongation factor eukaryotic elongation factor 1A (eEF1A) that together coordinate faithful tRNA incorporation at each mRNA codon. The distinct nature and timing of conformational changes within the ribosome and eEF1A rationalize how increased decoding fidelity is achieved and potentially regulated in eukaryotic species.


Asunto(s)
Bacterias , Biosíntesis de Proteínas , Humanos , Bacterias/genética , Bacterias/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Aminoacil-ARN de Transferencia/genética , Aminoacil-ARN de Transferencia/metabolismo , Imagen Individual de Molécula , Microscopía por Crioelectrón , Ribosomas/genética , Ribosomas/metabolismo
5.
Psychiatry Investig ; 20(1): 69-74, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36721888

RESUMEN

A growing number of neuroimaging studies have revealed abnormal brain structural and functional alterations in subjects with internet addiction (IA), however, with conflicting conclusions. We plan to conduct a systematic review and meta-analysis on the studies of voxelbased morphometry (VBM) and resting-state functional connectivity (rsFC), to reach a consolidated conclusion and point out the future direction in this field. A comprehensive search of rsFC and VBM studies of IA will be conducted in the PubMed, Cochrane Library, and Web of Science databases to retrieve studies published from the inception dates to August 2021. If the extracted data are feasible, activation likelihood estimation and seed-based d mapping methods will be used to meta-analyze the brain structural and functional changes in IA patients. This study will hopefully reach a consolidated conclusion on the impact of IA on human brain or point out the future direction in this field.

6.
Transfus Med Hemother ; 50(1): 39-50, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36818774

RESUMEN

Introduction: Autologous hematopoietic stem cell transplantation (ASCT) is a well-established treatment for patients with multiple myeloma (MM), and adequate stem cell collection must be assured before ASCT. However, prediction of poor mobilizers (PMs) is still difficult despite several risk factors for mobilization failure having been identified. Methods: We retrospectively analyzed MM patients at Taipei Veterans General Hospital in Taiwan who underwent stem cell collection between October 2006 and August 2020. A CD34+ cell collection of <1 × 106 cells/kg was defined as a mobilization failure. The primary endpoint was mobilization failure. The secondary endpoint was overall survival (OS). Odds ratios (ORs) and 95% confidence intervals (CIs) for mobilization failure were calculated using a logistic regression model. The cumulative incidence of mortality was estimated using the Kaplan-Meier method. Results: In the multivariate analysis, absolute monocyte count <500/µL (adjusted OR 10.75, 95% CI: 1.82-63.57, p = 0.009), platelet count <150,000/µL (adjusted OR 12.49, 95% CI: 2.65-58.89, p = 0.001) before mobilization, and time interval from diagnosis to stem cell harvest ≥180 days (adjusted OR 7.69, 95% CI: 1.61-36.87, p = 0.011) were risk factors for PMs. PM patients had poorer OS compared to patients with successful stem cell collection in the univariate analysis (log-rank test p = 0.027). The predicted probability of PMs was estimated by the multiple logistic regression model with a sensitivity of 84.6% and a specificity of 84.0%. Conclusion: Absolute monocyte count <500/µL, platelet count <150,000/µL, and treatment duration more than 180 days before stem cell mobilization are risk factors for unsuccessful stem cell collection. Our prediction models have high sensitivity and specificity for mobilization failure prediction and allow for early interventions for possible PMs.

7.
Cell ; 186(2): 346-362.e17, 2023 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-36638793

RESUMEN

Ribosomes frequently stall during mRNA translation, resulting in the context-dependent activation of quality control pathways to maintain proteostasis. However, surveillance mechanisms that specifically respond to stalled ribosomes with an occluded A site have not been identified. We discovered that the elongation factor-1α (eEF1A) inhibitor, ternatin-4, triggers the ubiquitination and degradation of eEF1A on stalled ribosomes. Using a chemical genetic approach, we unveiled a signaling network comprising two E3 ligases, RNF14 and RNF25, which are required for eEF1A degradation. Quantitative proteomics revealed the RNF14 and RNF25-dependent ubiquitination of eEF1A and a discrete set of ribosomal proteins. The ribosome collision sensor GCN1 plays an essential role by engaging RNF14, which directly ubiquitinates eEF1A. The site-specific, RNF25-dependent ubiquitination of the ribosomal protein RPS27A/eS31 provides a second essential signaling input. Our findings illuminate a ubiquitin signaling network that monitors the ribosomal A site and promotes the degradation of stalled translation factors, including eEF1A and the termination factor eRF1.


Asunto(s)
Proteínas de Unión al ARN , Transactivadores , Proteínas Portadoras/metabolismo , Factores de Elongación de Péptidos/genética , Biosíntesis de Proteínas , Proteínas Ribosómicas/metabolismo , Ribosomas/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación , Humanos , Células HeLa , Células HEK293 , Proteínas de Unión al ARN/metabolismo , Transactivadores/metabolismo , Factor 1 de Elongación Peptídica/metabolismo
8.
Cancer Med ; 12(7): 8089-8101, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36647765

RESUMEN

BACKGROUND: Frontline intensification (including consolidative whole-brain radiotherapy or high-dose chemotherapy with autologous stem-cell transplantation after induction therapy) has been proposed to treat primary central nervous system lymphoma (PCNSL). However, no prospective randomized trials have answered whether frontline intensification can offer a survival benefit to PCNSL patients. We aim to clarify the outcomes and survival influence of frontline intensification on real-world patients with different risk-stratified PCNSLs. METHODS: Between January 2003 and December 2016, 110 PCNSL adults were retrospectively included, and 76 patients achieved at least PR after induction therapy, including 38 patients who received frontline intensification. The median follow-up with the 31 survivors was 7.52 years. RESULTS: Of the 38 induction-completed patients who had not received frontline intensification, 95% achieved post-induction therapy CR/CRu; however, all inevitably recurred. In the 38 who received frontline intensification, CR/CRu improved from 45% (pre-frontline intensification) to 84% (post-frontline intensification), and they achieved significantly better PFS (non-reach vs. 522 days, p < 0.001) and OS (non-reach vs. 899 days, p < 0.001). Additionally, patients had similar PFS and OS rates when receiving HDC-ASCT and/or WBRT as frontline intensification. Frontline intensification significantly improved PFS and OS survival in higher-risk patients (intermediate/high IELSG risk, MSKCC group 2/3, or Nottingham/Barcelona score ≥ 2 points) but did not improve OS in lower-risk patients. Among the 38 patients who received frontline intensification, two had treatment-related mortality; 14 recurred after frontline intensification. MTX-based chemotherapy was the main salvage modality, and the median OS was 295 days after recurrence. Progressive disease and infection (especially pneumonia) are two major causes of mortality in patients who receive frontline intensification. CONCLUSIONS: When achieving CR/CRu/PR after induction chemotherapy, frontline intensification should be adopted to improve PFS and OS in real-world PCNSL patients, especially higher-risk patients.


Asunto(s)
Neoplasias del Sistema Nervioso Central , Trasplante de Células Madre Hematopoyéticas , Linfoma , Adulto , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Estudios Retrospectivos , Trasplante Autólogo , Terapia Combinada
9.
Hematol Oncol ; 41(1): 167-177, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36305496

RESUMEN

Hemophagocytic lymphohistiocytosis (HLH) is a heterogeneous group of hyperinflammatory statuses that are difficult to diagnose and can be life-threatening. Bone marrow (BM) hemophagocytosis is one of the diagnostic criteria according to HLH 2004 diagnostic criteria and HS score. Limited studies have focused on the prognostic factors of BM hemophagocytosis and its association with hematologic malignancies. We aimed to analyze the clinical significance of BM hemophagocytosis. Patients with BM hemophagocytosis, either by cytology or pathology, were enrolled at Taipei Veterans General Hospital from January 2002 to July 2021. Relevant clinical and laboratory data were extracted from medical records. Of 119 patients with BM hemophagocytosis, 57 were diagnosed with hematologic malignancies. The median age of the patients was 58, ranging from 21 to 90. Splenomegaly (adjusted odds ratio [aOR] 2.96; 95% confidence interval [CI] 1.13-7.79) was a risk factor for hematologic malignancies, while autoimmune disease (aOR 0.07; 95% CI 0.01-0.39) and increased D-dimer (aOR 0.25; 95% CI 0.07-0.92) were protective factors. Risk factors for mortality in patients with BM hemophagocytosis were hematologic malignancies (adjusted hazard ratio [aHR] 2.34; 95% CI 1.24-4.44), Eastern Cooperative Oncology Group score ≥3 (aHR 2.42; 95% CI 1.20-4.89) and thrombocytopenia (aHR 3.09; 95% CI 1.04-9.16). In conclusion, among patients with BM hemophagocytosis, splenomegaly was a predictor of hematologic malignancies. Patients with hematologic malignancies, poor performance status, or thrombocytopenia had a higher mortality risk. Further validation studies are warranted.


Asunto(s)
Neoplasias Hematológicas , Linfohistiocitosis Hemofagocítica , Humanos , Pronóstico , Médula Ósea/patología , Esplenomegalia/complicaciones , Esplenomegalia/patología , Linfohistiocitosis Hemofagocítica/etiología , Linfohistiocitosis Hemofagocítica/diagnóstico , Neoplasias Hematológicas/complicaciones , Neoplasias Hematológicas/patología , Estudios Retrospectivos
10.
Cancer Med ; 12(3): 3013-3026, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36127838

RESUMEN

BACKGROUND: Multiple myeloma (MM) is known for its immune disturbance and patients suffering from MM are thus vulnerable to opportunistic infections, including herpes zoster (HZ). As HZ infection remarkably affects patients' quality of life and poses huge economic burdens on the health system, we aim to identify the risk factors of HZ infection and evaluate the effects of different dosages, types, and durations of anti-HZ prophylaxis drugs to prevent HZ infection. METHODS: 551 MM patients at Taipei Veterans General Hospital in Taiwan between January 1, 2009 and August 31, 2021 were restrospectively analyzed. The patients' baseline characteristics were recorded. The primary endpoint of the study was the incidence of HZ infection among the studied patient population. Due to the lack of cost coverage from Taiwanese public health insurance on HZ prophylaxis drugs, the use of anti-HZ drugs mainly depends on physicians' preferences and patients' choices. RESULTS: In our study, prophylaxis was given to 283 of the patients. In the multivariate analysis, we included non-prophylaxis, age ≥ 60, corrected serum calcium ≥12 mg/dl, serum creatinine ≥2 mg/dl, serum ß2-microglobulin ≥5500 mg/L, autologous stem cell transplant (SCT), and allogeneic SCT for analysis. Our results demonstrated that the non-prophylaxis group (HR: 2.37, 95% CI 1.57-3.57) and patients receiving autologous SCT (HR: 2.22, 95% CI 1.28-3.86) and allogeneic SCT (HR: 5.12, 95% CI 1.13-23.22) had higher risk of HZ infection. The difference in dosage and types of anti-HZ drugs showed similar protective effects. In patients who stopped anti-HZ prophylaxis before active cancer-related treatment, a higher risk of getting HZ infection compared to the corresponding group was also observed (adjusted HR 3.09, 95% CI 1.35-7.07, p = 0.008). CONCLUSIONS: We concluded that MM patients should receive HZ prophylaxis drugs while receiving active cancer-related treatment. Patients receiving SCT are also at high risk of getting HZ infection, even under prophylaxis.


Asunto(s)
Herpes Zóster , Mieloma Múltiple , Humanos , Mieloma Múltiple/terapia , Calidad de Vida , Herpes Zóster/tratamiento farmacológico , Herpes Zóster/epidemiología , Herpes Zóster/prevención & control , Factores de Riesgo , Trasplante de Células Madre/efectos adversos , Incidencia , Estudios Retrospectivos
11.
Medicine (Baltimore) ; 101(39): e30723, 2022 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-36181054

RESUMEN

Bladder cancer (BC) is one of the most common male malignant tumors and the most common urological tumor. However, the molecular mechanism and role of PLK1 on bladder cancer were unclear. Therefore, the study aims to explore the potential part of the overall survival of bladder cancer through bioinformatics analysis. GSE121711 and GSE130598, from the Gene Expression Omnibus database. The GEO2R screened differently expressed genes, and DAVID and Metascape were used for functional annotation. The cytoHubba made hub genes identification and expression. A total of 50 BC participants were recruited. After surgery, 50 BC tumor samples from BC patients and 50 adjacent standard bladder tissue samples were obtained. The RT-qPCR assay was performed to verify the expression of hub genes. The Kaplan-Meier Plotter analyzed the effect of hub gene expression for overall survival of BC. The compulsory module of Molecular Complex Detection tool analysis was shown, which included CDK1, TTK, AURKB, MELK, PLK1, and BUB1. And the six hub genes were up-regulated in the BC compared with the normal tissues. The relative expression levels of CDK1, TTK, AURKB, MELK, PLK1, and BUB1 were significantly higher in BC samples compared with the regular kidney tissue groups. The result demonstrated that CDK1, TTK, AURKB, MELK, PLK1, and BUB1 might be considered biomarkers for BC. Overall survival analysis showed that BC patients with high expression level of PLK1 had poorer overall survival times than those with low expression level (P < .05). The expression levels of CDK1, TTK, AURKB, MELK, and BUB1 was not related to the overall survival of BC patients (P > .05). The PLK1 gene might provide new ideas and evidence for bladder cancer research.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Neoplasias de la Vejiga Urinaria , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Biología Computacional , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Pronóstico , Proteínas Serina-Treonina Quinasas/genética , Neoplasias de la Vejiga Urinaria/genética , Quinasa Tipo Polo 1
12.
Nat Chem ; 14(12): 1443-1450, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36123449

RESUMEN

Ternatin-family cyclic peptides inhibit protein synthesis by targeting the eukaryotic elongation factor-1α. A potentially related cytotoxic natural product ('A3') was isolated from Aspergillus, but only 4 of its 11 stereocentres could be assigned. Here, we synthesized SR-A3 and SS-A3-two out of 128 possible A3 epimers-and discovered that synthetic SR-A3 is indistinguishable from naturally derived A3. Relative to SS-A3, SR-A3 exhibits an enhanced residence time and rebinding kinetics, as revealed by single-molecule fluorescence imaging of elongation reactions catalysed by eukaryotic elongation factor-1α in vitro. An increased residence time-stereospecifically conferred by the unique ß-hydroxyl in SR-A3-was also observed in cells. Consistent with its prolonged duration of action, thrice-weekly dosing with SR-A3 led to a reduced tumour burden and increased survival in an aggressive Myc-driven mouse lymphoma model. Our results demonstrate the potential of SR-A3 as a cancer therapeutic and exemplify an evolutionary mechanism for enhancing cyclic peptide binding kinetics via stereospecific side-chain hydroxylation.


Asunto(s)
Antineoplásicos , Imagen Individual de Molécula , Animales , Ratones , Cinética , Antineoplásicos/farmacología , Péptidos Cíclicos/farmacología
13.
ACS Chem Biol ; 16(8): 1354-1364, 2021 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-34251165

RESUMEN

Cordyheptapeptide A is a lipophilic cyclic peptide from the prized Cordyceps fungal genus that shows potent cytotoxicity in multiple cancer cell lines. To better understand the bioactivity and physicochemical properties of cordyheptapeptide A with the ultimate goal of identifying its cellular target, we developed a solid-phase synthesis of this multiply N-methylated cyclic heptapeptide which enabled rapid access to both side chain- and backbone-modified derivatives. Removal of one of the backbone amide N-methyl (N-Me) groups maintained bioactivity, while membrane permeability was also preserved due to the formation of a new intramolecular hydrogen bond in a low dielectric solvent. Based on its cytotoxicity profile in the NCI-60 cell line panel, as well as its phenotype in a microscopy-based cytological assay, we hypothesized that cordyheptapeptide was acting on cells as a protein synthesis inhibitor. Further studies revealed the molecular target of cordyheptapeptide A to be the eukaryotic translation elongation factor 1A (eEF1A), a target shared by other lipophilic cyclic peptide natural products. This work offers a strategy to study and improve cyclic peptide natural products while highlighting the ability of these lipophilic compounds to effectively inhibit intracellular disease targets.


Asunto(s)
Antineoplásicos/farmacología , Factor 1 de Elongación Peptídica/antagonistas & inhibidores , Péptidos Cíclicos/farmacología , Inhibidores de la Síntesis de la Proteína/farmacología , Antineoplásicos/síntesis química , Línea Celular Tumoral , Humanos , Estructura Molecular , Péptidos Cíclicos/síntesis química , Biosíntesis de Proteínas/efectos de los fármacos , Inhibidores de la Síntesis de la Proteína/síntesis química , Técnicas de Síntesis en Fase Sólida , Relación Estructura-Actividad
14.
Chem Commun (Camb) ; 57(18): 2265-2268, 2021 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-33533357

RESUMEN

Novel purine-based iridium complexes were designed for selective determination of ER viscosity. The Ir-PH possessed excellent ER targeting ability and could distinguish the viscosity changes under ER stress by fluorescence lifetime image microscopy (FLIM), which may accelerate the development of relative quantitative detection of microenvironment changes at the subcellular level.


Asunto(s)
Complejos de Coordinación/metabolismo , Estrés del Retículo Endoplásmico/fisiología , Retículo Endoplásmico/metabolismo , Iridio/química , Purinas/química , Células A549 , Complejos de Coordinación/química , Fluorescencia , Humanos , Procesamiento de Imagen Asistido por Computador , Microscopía Fluorescente/métodos , Viscosidad
15.
Support Care Cancer ; 29(7): 3991-3999, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33398428

RESUMEN

PURPOSE: Multiple myeloma (MM), a clonal plasma cell malignancy, composes around 10% of hematologic malignancies. Though recent advances in treatment have dramatically improved MM survival, some aggressive courses of disease and dismal outcomes still exist. Low body weight, undernutrition, and cachexia are noted at MM diagnosis. We aim to evaluate the impact of low body mass index (BMI) and undernutrition in MM patients. METHODS: We retrospectively analyzed MM patients at Taipei Veterans General Hospital in Taiwan between January 1, 2006 and October 31, 2018. Being underweight is defined as having a BMI of under 18.5 kg/m2. The patient's baseline characteristics, including BMI, serum albumin level, and comorbidities, etc., were recorded. The primary endpoint of the study was all-cause mortality. A Cox regression model was used to estimate the risk factors of mortality. RESULTS: A total of 378 newly diagnosed MM patients were enrolled in this study. The median age of the patients was 69. Thirty patients (7.9%) were underweight at diagnosis. The median overall survival was 1.3 years (95% CI 0.3-5.7) and 5.0 years (95% CI 3.1-5.9) for patients with low BMI and for patients with normal or higher BMI, respectively. In the multivariate analysis, low BMI (95% CI 1.07-4.44), ECOG ≥2 (95% CI 1.02-2.89), hypoalbuminemia (95% CI 1.21-4.01), high LDH (95% CI 1.22-3.49), and light chain ratio > 100 (95% CI 1.06-2.77) were independent risk factors of mortality. CONCLUSION: MM patients who were underweight, with hypoalbuminemia, poor performance status, higher LDH, and light chain ratio > 100 were associated with poor overall survival.


Asunto(s)
Caquexia/complicaciones , Caquexia/mortalidad , Mieloma Múltiple/complicaciones , Delgadez/complicaciones , Delgadez/mortalidad , Anciano , Femenino , Humanos , Masculino , Mieloma Múltiple/mortalidad , Estudios Retrospectivos , Factores de Riesgo , Análisis de Supervivencia
16.
Ann Hematol ; 99(8): 1813-1822, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32607596

RESUMEN

Infection is associated with great morbidity and mortality in patients with multiple myeloma (MM), but evidence for invasive fungal infections (IFIs) is lacking. We aimed to investigate risk factors for IFI in MM patients and to determine its impact on patients' survival. We retrospectively analyzed MM patients at Taipei Veterans General Hospital in Taiwan between January 2002 and October 2018. MM was diagnosed according to the International Myeloma Working Group criteria. IFI was defined according to the European Organization for Research and Treatment of Cancer/Mycoses Study Group criteria. All risk factors of IFI in MM patients were estimated using Cox regression models in the univariate and multivariate analyses. Of the 623 patients recruited, 22 (3.5%) were diagnosed with proven or probable IFI. Light chain disease (adjusted hazard ratio [HR] 6.74, 95% confidence interval [CI] 2.10-21.66), hemoglobin less than 8 g/dl (adjusted HR 3.34, 95% CI 1.32-8.42), serum albumin < 3.5 g/dl (adjusted HR 3.24, 95% CI 1.09-9.68), and having received allogeneic stem cell transplantation (allo-SCT) (adjusted HR 5.98, 95% CI 1.62-22.03) were significantly associated with IFI in the multivariate analysis. Contracting IFI was in turn associated with early mortality (adjusted HR 11.60, 95% CI 1.26-106.74). Light chain disease, anemia, hypoalbuminemia, and receiving allo-SCT were independent predictors of IFI in MM patients. The early mortality risk is much higher in those encountering IFI. Physicians must be aware of the rare but potentially lethal infections.


Asunto(s)
Infecciones Fúngicas Invasoras/epidemiología , Infecciones Fúngicas Invasoras/terapia , Mieloma Múltiple/epidemiología , Mieloma Múltiple/terapia , Trasplante de Células Madre , Adulto , Anciano , Anciano de 80 o más Años , Aloinjertos , Femenino , Humanos , Infecciones Fúngicas Invasoras/sangre , Infecciones Fúngicas Invasoras/etiología , Masculino , Persona de Mediana Edad , Mieloma Múltiple/sangre , Factores de Riesgo
17.
J Chin Med Assoc ; 83(8): 743-750, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32371665

RESUMEN

BACKGROUND: Thrombotic microangiopathy (TMA) syndromes are potentially life-threatening complications and are defined as integrated syndromes of microangiopathic hemolytic anemia, thrombocytopenia, and organ injury. Systemic lupus erythematosus (SLE) is an autoimmune disease that can affect various organs, including the hematopoietic system. SLE can complicate with TMA and can be categorized into two distinct groups by chronological association: TMA occurring as the initial presentation and leading to a diagnosis of SLE concurrently (TMA-cSLE) or TMA developing in patients previously diagnosed as having SLE (TMA-pSLE). We examined the differences in clinical characteristics, treatment responses, and clinical outcomes between these groups. METHODS: We reviewed data of patients diagnosed as having TMA and SLE at Taipei Veterans General Hospital between 2002 and 2013. We included 29 patients: 8 and 21 in TMA-cSLE and TMA-pSLE groups, respectively. All underwent plasma exchange. Patients' demographic and clinical characteristics, disease activity, and treatment modality were summarized. RESULTS: Overall survival (OS) from SLE or TMA diagnosis was poor for the TMA-cSLE group. Median OS from SLE diagnosis was 2.9 months in the TMA-cSLE group and 103.5 months in the TMA-pSLE group (p < 0.001). Median OS from TMA diagnosis was 2.9 months in the TMA-cSLE group and 10.7 months in the TMA-pSLE group (p = 0.58). Time to TMA remission after treatment appeared longer in the TMA-cSLE group (38.00 vs 10.76 days). Multivariate Cox analysis revealed TMA-cSLE and anti-RNP positivity were independent risk factors for mortality in SLE patients with TMA. CONCLUSION: The occurrence of TMA with SLE is rare, and its vigorous course results in high mortality and morbidity rates. In patients without a history of autoimmune disease, early suspicion of TMA and working-up for SLE under this condition are vital. Early recognition of TMA-cSLE and prompt plasma exchange with upfront immunosuppressive therapies for TMA-cSLE patients or anti-RNP-positive patients may improve their prognosis.


Asunto(s)
Lupus Eritematoso Sistémico/complicaciones , Microangiopatías Trombóticas/etiología , Adulto , Femenino , Humanos , Lupus Eritematoso Sistémico/mortalidad , Lupus Eritematoso Sistémico/terapia , Masculino , Intercambio Plasmático , Pronóstico , Estudios Retrospectivos , Ribonucleoproteínas/inmunología , Microangiopatías Trombóticas/mortalidad , Microangiopatías Trombóticas/terapia , Adulto Joven
18.
J Med Case Rep ; 14(1): 43, 2020 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-32183896

RESUMEN

BACKGROUND: Extranodal natural killer/T cell lymphoma, nasal type, is one of the more common subtypes of mature T cell lymphoma, especially in the Far East Asian population. This aggressive histologic subtype of peripheral T cell lymphomas is frequently susceptible to exposure of Epstein-Barr virus infection. The optimal treatment is not well elucidated. For stage IV disseminated extranodal natural killer/T cell lymphoma, induction chemotherapy with consolidative autologus or allogeneic hematopoietic stem cell transplantation is recommended as the major first-line treatment. However, there is controversy over which type of chemotherapy is most appropriate and effective as a bridge to autologus or allogeneic hematopoietic stem cell transplantation in patients with newly diagnosed disseminated advanced-stage or relapsed extranodal natural killer/T cell lymphoma because of cancer chemoresistance or associated complications. Pralatrexate is the first US Food and Drug Administration-approved novel agent for the treatment of refractory/recurrent peripheral T cell lymphomas. In our case, pralatrexate was used as a successful bridge to allogeneic hematopoietic stem cell transplantation in a patient with advanced-stage disseminated extranodal natural killer/T cell lymphoma refractory to first-line chemotherapy. CASE PRESENTATION: We presented a case report of a 29-year-old Asian man diagnosed as having stage IV disseminated extranodal natural killer/T cell lymphoma, nasal type, with skin and bone marrow involvement, whose disease was primary refractory to first-line dexamethasone, methotrexate, ifosfamide, L-asparaginase, and etoposide chemotherapy, but obviously responded to treatment with two cycles of single-agent pralatrexate treatment. Monitoring Epstein-Barr virus viremia revealed dramatic downregulation. In addition to complete remission of the involvement of bone marrow and nasal cavity, skin involvement also obtained partial remission. The extranodal natural killer/T cell lymphoma successfully achieved complete remission after a bridge to allogeneic hematopoietic stem cell transplantation. CONCLUSIONS: This is the first study to present pralatrexate as a successful bridge to allogeneic hematopoietic stem cell transplantation in a 29-year-old Asian male patient with advanced-stage extranodal natural killer/T cell lymphoma refractory to first-line dexamethasone, methotrexate, ifosfamide, L-asparaginase, and etoposide chemotherapy. This case provides a novel treatment opinion for extranodal natural killer/T cell lymphoma, especially for the Far East Asian population.


Asunto(s)
Aminopterina/análogos & derivados , Trasplante de Células Madre Hematopoyéticas , Linfoma Extranodal de Células NK-T/terapia , Acondicionamiento Pretrasplante , Adulto , Aloinjertos/efectos de los fármacos , Aminopterina/uso terapéutico , Humanos , Masculino , Estadificación de Neoplasias , Inducción de Remisión , Taiwán/epidemiología
19.
Cancer Med ; 9(6): 2134-2145, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32011103

RESUMEN

BACKGROUND: Although various prognostic models for primary central nervous system lymphoma (PCNSL) have been developed, there is no consensus regarding the optimal prognostic index. We aimed to evaluate potential prognostic factors and construct a novel predictive model for PCNSL patients. METHODS: We enrolled newly diagnosed PCNSL patients between 2003 and 2015. The primary endpoint was progression-free survival (PFS), and the secondary endpoint was overall survival (OS). The prognostic factors identified using multivariate Cox proportional hazards models were used to develop a predictive model. We subsequently validated the prognostic model in an independent cohort. We also evaluated the validity of the existing scores: the International Extranodal Lymphoma Study Group (IELSG), the Nottingham/Barcelona (NB), and the Memorial Sloan-Kettering Cancer Center models (MSKCC). RESULTS: We identified 101 patients with newly diagnosed PCNSL at our center. Multivariate analysis showed that age ≥80, deep brain lesions, and ECOG ≥2 were independent risk factors of PFS. Assigning one point for each factor, we constructed a novel prognostic model, the Taipei Score, with four distinct risk groups (0-3 points). The performances of the Taipei Score in discriminating both PFS and OS in the training cohort were significant, and the score was validated in the external validation cohort. The IELSG, NB and MSKCC models had insufficient discriminative ability for either PFS or OS in both cohorts. CONCLUSION: The Taipei Score is a simple model that discriminates PFS and OS for PCNSL patients. The score may offer disease risk stratification and facilitate clinical decision-making.


Asunto(s)
Neoplasias del Sistema Nervioso Central/mortalidad , Linfoma no Hodgkin/mortalidad , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias del Sistema Nervioso Central/sangre , Neoplasias del Sistema Nervioso Central/diagnóstico , Neoplasias del Sistema Nervioso Central/terapia , Quimioradioterapia/métodos , Toma de Decisiones Clínicas/métodos , Irradiación Craneana , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Linfoma no Hodgkin/sangre , Linfoma no Hodgkin/diagnóstico , Linfoma no Hodgkin/terapia , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Supervivencia sin Progresión , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Medición de Riesgo/métodos , Factores de Riesgo , Adulto Joven
20.
Org Lett ; 22(4): 1495-1498, 2020 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-32026682

RESUMEN

A general method has been developed for the formation of glycosyl chlorides and bromides from picolinic esters under mild and neutral conditions. Benchtop stable picolinic esters are activated by a copper(II) halide species to afford the corresponding products in high yields with a traceless leaving group. Rare ß glycosyl chlorides are accessible via this route through neighboring group participation. Additionally, glycosyl chlorides with labile protecting groups previously not easily accessible can be prepared.


Asunto(s)
Bromuros/síntesis química , Quelantes/química , Cloruros/síntesis química , Ésteres/química , Glicósidos/síntesis química , Picolinas/química , Bromuros/química , Cloruros/química , Glicósidos/química , Estructura Molecular
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