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1.
Cancer Cell Int ; 22(1): 36, 2022 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-35073926

RESUMEN

BACKGROUND: To determine whether concurrent chemotherapy is necessary during locoregional radiotherapy (RT) after palliative chemotherapy (PCT) in patients with de novo metastatic nasopharyngeal carcinoma (mNPC). METHODS: A total of 746 patients with mNPC from 2000 to 2017 at our hospital were retrospectively reviewed. Among them, 355 patients received PCT followed by RT. Overall survival (OS) and progression-free survival (PFS), including locoregional progression-free survival (LRPFS) and distant progression-free survival (DPFS) were estimated with the Kaplan-Meier method and log-rank test. Cox proportional-hazards models, landmark analyses, propensity score matching, and subgroup analyses were used to address confounding. RESULTS: Of the patients included in our study, 192 received radiotherapy alone after PCT (PCT + RT), and 163 received concurrent chemoradiotherapy after PCT (PCT + CCRT). The prognosis of PCT + CCRT was significantly better than that of PCT + RT (5 year OS, 53.0 vs 36.2%; P = 0.004). After matching, the 5 year OS rates of the two groups were 55.7 and 39.0%, respectively (P = 0.034) and the median DPFS were 29.4 and 18.7 months, respectively (P = 0.052). Multivariate Cox regression analysis indicated that PCT + CCRT was an independent favorable prognostic factor (P = 0.009). In addition, conducting concurrent chemoradiotherapy after 4-6 cycles of PCT or conducting concurrent chemotherapy with single-agent platinum was associated with significant survival benefit in the matched cohort (5 year OS rate, 60.4 or 57.4%, respectively). The survival difference between groups remained significant when evaluating patients who survived for ≥ 1 year (P = 0.028). CONCLUSIONS: The optimal treatment strategy of mNPC is the combination of PCT followed by concurrent chemoradiotherapy. More specifically, concurrent chemoradiotherapy with single-agent platinum after 4-6 cycles of PCT is suggested.

2.
J Cell Physiol ; 234(9): 15035-15043, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30680718

RESUMEN

Hypoxia is a common biological hallmark of solid cancers, which has been proposed to be associated with oncogenesis and chemotherapy resistance. The purpose of the present study was to investigate the role and underlying mechanisms of olfactomedin 4 (OLFM4) in the hypoxia-induced invasion, epithelial-mesenchymal transition (EMT), and chemotherapy resistance of non-small-cell lung cancer (NSCLC). We observed dramatically upregulated expression of OLFM4 in several NSCLC cell lines, and this effect was more pronounced in A549 and H1299 cells. In addition, our data revealed that OLFM4 expression was remarkably increased in both A549 and H1299 cells under hypoxic microenvironment, accompanied by enhanced levels of hypoxia-inducible factor (HIF)-1α protein. The HIF-1α level was elevated in response to hypoxia, resulting in the regulation of OLFM4. Interestingly, OLFM4 was a positive regulator of hypoxia-driven HIF-1α production. Moreover, depletion of OLFM4 modulated multiple EMT-associated proteins, as evidenced by the enhanced E-cadherin levels along with the diminished expression of N-cadherin and vimentin in response to hypoxia, and thus blocked invasion ability of A549 and H1299 cells following exposure to hypoxia. Furthermore, ablation of OLFM4 accelerated the sensitivity of A549 cells to cisplatin under hypoxic conditions, implying that OLFM4 serves as a key regulator in chemotherapeutic resistance under hypoxia. In conclusion, OLFM4/HIF-1α axis might be a potential therapeutic strategy for NSCLC.

3.
J Cell Biochem ; 120(9): 15369-15377, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31038794

RESUMEN

Long noncoding RNAs (lncRNAs) have been implicated in colorectal cancer (CRC). And lncRNA RP11-138J23.1 (CRCAL-3) was previously reported as a candidate regulator of CRC development. But its regulating functions have not been fully elucidated. Here, we analyzed RNA sequencing data from the Cancer Genome Atlas (TCGA) and 253 CRC patients treated in our hospital to assess expression dysregulation of CRCAL-3, and the correlation between CRCAL-3 expression and disease progression. Further, polymerase chain reaction (PCR) assay on different cell lines and knockdown experiments by small interfering RNA were performed to assess functions of CRCAL-3 in proliferation and migration of CRC cells. As a result, analyses on TCGA datasets showed an upregulated CRCAL-3 expression in 14 solid tumors, including CRC. PCR assay on 253 cases of CRC tissue and 114 cases of normal adjacent tissue confirmed this expression upregulation. Also, CRCAL-3 expression was exhibited by survival analyses on the 253 CRC patients, to have a negative correlation with patients' overall and progression-free survivals. PCR assay on different cell lines showed that CRC cells expressed a higher level of CRCAL-3, compared with normal colonic epithelial cells. In vitro knockdown of CRCAL-3 resulted in an obvious retardation of proliferation and migration in two CRC cell lines (HCT116 and DLD-1). Moreover, CRCAL-3 knockdown was observed in xenograft models to repress cell proliferation and enhance cisplatin sensitivity. Taking these results together, CRCAL-3 emerged as a biomarker for early diagnosis, prognosis prediction, and individualized treatment of CRC.


Asunto(s)
Neoplasias Colorrectales/patología , Perfilación de la Expresión Génica/métodos , ARN Largo no Codificante/genética , Regulación hacia Arriba , Animales , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Neoplasias Colorrectales/genética , Progresión de la Enfermedad , Femenino , Regulación Neoplásica de la Expresión Génica , Células HCT116 , Humanos , Masculino , Ratones , Trasplante de Neoplasias , Análisis de Secuencia de ARN , Análisis de Supervivencia
4.
Cancer Cell Int ; 19: 141, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31139018

RESUMEN

BACKGROUND: Whether PD-L1/PD-1 expression plays a significant role in the prognosis of NPC is still controversial. The present study mainly aimed to investigate the prognostic significance of PD-L1/PD-1 expression in patients with NPC. METHODS: A systematical research was performed in the PubMed, Web of Science, EMBASE, and the Cochrane Library databases up to January 06, 2019. Eighteen studies met eligible criteria were included in the meta-analysis. Quality assessment of included articles was evaluated by Newcastle-Ottawa quality assessment scale (NOS). Pooled hazard ratios (HRs) and their corresponding 95% confidence intervals (95% CIs) were used to elucidated the primary endpoint, overall survival (OS), and the secondary endpoints. Furthermore, the relationship between clinicopathological features of NPC and PD-L1/PD-1 expression was estimated by relative ratios (RRs) and 95% CIs. RESULTS: A total of 1836 patients from 15 included studies concerning PD-L1 and 678 patients from six studies regarding PD-1 were included in the meta-analysis. Pooled results revealed that PD-L1 expression in NPC did not correlate with OS (HR 1.34 95% CI 0.93-1.93, p = 0.11), DFS (HR 1.82, 95% CI 0.86-3.85, p = 0.12), PFS (HR 1.19, 95% CI 0.46-3.08, p = 0.72), and DMFS (HR 2.26, 95% CI 0.60-8.56, p = 0.23). Meanwhile, no statistically significant differences existed between the expression level of PD-1 in tumor infiltrating lymphocytes (TILs) and the OS in NPC, with the pooled HR 1.29 (95% CI 0.68-2.42, p = 0.44). In subgroup analysis, higher expression of PD-L1 in immune cells correlated with better OS in patients with NPC, with a pooled HR 0.68 (95% CI 0.47-0.99, p = 0.04). Among the clinicopathological features included in our study, we found that the positive expression of PD-L1 in NPC associated with the higher expression of PD-1 (RR 1.25, 95% CI 1.02-1.52, p = 0.03). CONCLUSIONS: Our meta-analysis indicated that higher/positive expression of PD-L1/PD-1 may not serve as suitable biomarkers for the prognosis of NPC, which was not in consistent with some previous studies about the prognostic value of PD-L1/PD-1 in other types of tumors. Despite the positive results in subgroup analysis and study about clinicopathological features, it may still need corroboration of prospective and large-scale studies.

5.
Nucleic Acids Res ; 44(18): 8786-8798, 2016 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-27407105

RESUMEN

In eukaryotic cells the CDC7/DBF4 kinase, also known as DBF4-dependent kinase (DDK), is required for the firing of DNA replication origins. CDC7 is also involved in replication stress responses and its depletion sensitises cells to drugs that affect fork progression, including Topoisomerase 2 poisons. Although CDC7 is an important regulator of cell division, relatively few substrates and bona-fide CDC7 phosphorylation sites have been identified to date in human cells. In this study, we have generated an active recombinant CDC7/DBF4 kinase that can utilize bulky ATP analogues. By performing in vitro kinase assays using benzyl-thio-ATP, we have identified TOP2A as a primary CDC7 substrate in nuclear extracts, and serine 1213 and serine 1525 as in vitro phosphorylation sites. We show that CDC7/DBF4 and TOP2A interact in cells, that this interaction mainly occurs early in S-phase, and that it is compromised after treatment with CDC7 inhibitors. We further provide evidence that human DBF4 localises at centromeres, to which TOP2A is progressively recruited during S-phase. Importantly, we found that CDC7/DBF4 down-regulation, as well S1213A/S1525A TOP2A mutations can advance the timing of centromeric TOP2A recruitment in S-phase. Our results indicate that TOP2A is a novel DDK target and have important implications for centromere biology.


Asunto(s)
Antígenos de Neoplasias/metabolismo , Proteínas de Ciclo Celular/metabolismo , Centrómero/genética , Centrómero/metabolismo , ADN-Topoisomerasas de Tipo II/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas de Ciclo Celular/antagonistas & inhibidores , Replicación del ADN , Humanos , Fosforilación , Proteínas de Unión a Poli-ADP-Ribosa , Unión Proteica , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Origen de Réplica , Fase S
6.
Mol Reprod Dev ; 84(6): 517-524, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28383772

RESUMEN

Incomplete reprogramming of a donor nucleus following somatic cell nuclear transfer (SCNT) results in aberrant expression of developmentally important genes, and is the primary source of the phenotypic abnormalities observed in cloned animals. Expression of non-coding RNAs in the murine Dlk1-Dio3 imprinted domain was previously shown to correlate with the pluripotency of mouse induced pluripotent stem cells. In this study, we examined the transcription of the bovine orthologs from this locus, MICO1 (Maternal intergenic circadian oscillating 1) and MICO1OS (MICO1 opposite strand), in tissues from artificially inseminated and SCNT calves that died during the perinatal period. A single-nucleotide polymorphism (SNP), a T-to-C transition, was used to analyze the allelic transcription of MICO1. Our results indicate monoallelic expression of the MICO1C allele among the six analyzed tissues (heart, liver, spleen, lung, kidney, and brain) of artificially inseminated calves, indicating that this gene locus may be imprinted in bovine. Conversely, we observed variable allelic transcription of MICO1 in SCNT calves. We asked if DNA methylation regulated the monoallelic expression of MICO1 and MICO1OS by evaluating the methylation levels of six regions within or around this locus in tissues with normal or aberrant MICO1 transcription; all of the samples from either artificially inseminated or SCNT calves exhibited hypermethylation, implying that DNA methylation may not be involved in regulating its monoallelic expression. Furthermore, three imprinted genes (GTL2, MEG9, and DIO3) nearby MICO1 showed monoallelic expression in SCNT calves with aberrant MICO1 transcription, indicating that not all of the genes in the bovine DLK1-DIO3 domain are mis-regulated.


Asunto(s)
Clonación de Organismos , Regulación de la Expresión Génica/genética , Sitios Genéticos , Impresión Genómica , Técnicas de Transferencia Nuclear , Polimorfismo de Nucleótido Simple , Animales , Bovinos , Transcripción Genética/genética
7.
Artículo en Inglés | MEDLINE | ID: mdl-28723584

RESUMEN

Phenotypic flexibility in traits can allow organisms to cope with environmental challenges. However, the ecological consequences (e.g., growth) of SMR flexibility in fish are poorly understood. Juvenile qingbo (Spinibarbus sinensis) were reared individually with two levels of food resources (satiation or limited) with either continuous feeding (CF) or starvation-refeeding (SR). In the CF experiment, SMR increased when individuals were fed either the satiation or limited diets, but no difference was found in average specific growth rate somatic growth (SGR) between the two food availabilities. The relationship between flexibility in SMR and SGR, feeding efficiency (FE) and food intake (FI) was positive in the satiation group but not in the limited food group. In the SR experiment, the initial SMR of individuals was negatively correlated with the SGR during starvation. During refeeding, the starved individuals increased both body mass and SMR under both food availabilities. Individuals with a greater increase in SMR were fed more and also had greater SGR and FE under the satiation diet, but these results were not observed under the limited diet. The average FE under the limited diet was greater than that under the satiation diet, causing there to be no significant difference in final body mass between the diet treatments at the end of refeeding. Our study suggested that SMR flexibility can allow individuals to maximize their potential growth performance in an environment with changing food availability, and the benefits from greater flexibility in SMR could be offset by their maintenance metabolism under environmental stress.


Asunto(s)
Conducta Alimentaria , Peces/crecimiento & desarrollo , Animales , Peces/metabolismo , Peces/fisiología
8.
Cell Discov ; 10(1): 70, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38937452

RESUMEN

KRAS mutations are highly prevalent in a wide range of lethal cancers, and these mutant forms of KRAS play a crucial role in driving cancer progression and conferring resistance to treatment. While there have been advancements in the development of small molecules to target specific KRAS mutants, the presence of undruggable mutants and the emergence of secondary mutations continue to pose challenges in the clinical treatment of KRAS-mutant cancers. In this study, we developed a novel molecular tool called tumor-targeting KRAS degrader (TKD) that effectively targets a wide range of KRAS mutants. TKD is composed of a KRAS-binding nanobody, a cell-penetrating peptide selectively targeting cancer cells, and a lysosome-binding motif. Our data revealed that TKD selectively binds to KRAS in cancer cells and effectively induces KRAS degradation via a lysosome-dependent process. Functionally, TKD suppresses tumor growth with no obvious side effects and enhances the antitumor effects of PD-1 antibody and cetuximab. This study not only provides a strategy for developing drugs targeting "undruggable" proteins but also reveals that TKD is a promising therapeutic for treating KRAS-mutant cancers.

9.
BMC Bioinformatics ; 14: 41, 2013 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-23384097

RESUMEN

BACKGROUND: Interferon-gamma (IFN-gamma) and interleukin-6 (IL-6) are multifunctional cytokines that regulate immune responses, cell proliferation, and tumour development and progression, which frequently have functionally opposing roles. The cellular responses to both cytokines are activated via the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway. During the past 10 years, the crosstalk mechanism between the IFN-gamma and IL-6 pathways has been studied widely and several biological hypotheses have been proposed, but the kinetics and detailed crosstalk mechanism remain unclear. RESULTS: Using established mathematical models and new experimental observations of the crosstalk between the IFN-gamma and IL-6 pathways, we constructed a new crosstalk model that considers three possible crosstalk levels: (1) the competition between STAT1 and STAT3 for common receptor docking sites; (2) the mutual negative regulation between SOCS1 and SOCS3; and (3) the negative regulatory effects of the formation of STAT1/3 heterodimers. A number of simulations were tested to explore the consequences of cross-regulation between the two pathways. The simulation results agreed well with the experimental data, thereby demonstrating the effectiveness and correctness of the model. CONCLUSION: In this study, we developed a crosstalk model of the IFN-gamma and IL-6 pathways to theoretically investigate their cross-regulation mechanism. The simulation experiments showed the importance of the three crosstalk levels between the two pathways. In particular, the unbalanced competition between STAT1 and STAT3 for IFNR and gp130 led to preferential activation of IFN-gamma and IL-6, while at the same time the formation of STAT1/3 heterodimers enhanced preferential signal transduction by sequestering a fraction of the activated STATs. The model provided a good explanation of the experimental observations and provided insights that may inform further research to facilitate a better understanding of the cross-regulation mechanism between the two pathways.


Asunto(s)
Interferón gamma/farmacología , Interleucina-6/farmacología , Modelos Biológicos , Quinasas Janus/metabolismo , Factor de Transcripción STAT1/metabolismo , Factor de Transcripción STAT3/metabolismo , Transducción de Señal , Proteínas Supresoras de la Señalización de Citocinas/metabolismo
10.
Medicine (Baltimore) ; 102(20): e33850, 2023 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-37335697

RESUMEN

RATIONALE: Only 20 cases of pediatric primary renal non-Hodgkin's lymphoma have been reported since 1995, rare cases and a variety of imaging manifestations have led to difficulties in its diagnosis and treatment. PATIENT CONCERNS: Herein, we share in detail a case of primary renal lymphoma (PRL) in a child and summarize the common clinical manifestations, imaging features, and prognostic factors of pediatric PRL by retrospectively analyzing cases reported in the literature. A 2-year-old boy presented to the clinic with a large mass on the right side of his abdomen along with loss of appetite. DIAGNOSES: Imaging revealed a large right renal mass, nearly replacing the entire renal tissue, along with numerous small nodules in the left kidney. Given no local adenopathy and metastases, the diagnosis was unclear. A percutaneous renal puncture was performed, which proved the diagnosis of Burkitt's lymphoma. Since no bone marrow involvement, this child was diagnosed with pediatric PRL. INTERVENTIONS: This PRL boy was treated with the NHL-BFM95 protocol and supportive care. OUTCOMES: Unfortunately, this boy died of multiple organ failure in the fifth month of treatment. LESSONS: As per literature review, the presentation of pediatric PRL is fatigue, loss of appetite, weight loss, abdominal swelling, or other nonspecific symptoms. Although in 81% of cases it often infiltrates the bilateral kidneys, urine abnormalities caused by pediatric PRL are uncommon. 76.2% of pediatric PRL were boys and 2/3 of all cases presented as diffuse renal enlargement. Those PRL presented as masses could easily be misdiagnosed as WT or other malignancies. Absent of local enlarged lymph node, no necrosis or calcification suggest atypical presentation of renal masses and a percutaneous biopsy is needed in timely establishing the accurate diagnosis for appropriate treatment. Based on our experience, percutaneous renal puncture core biopsy is a safe procedure.


Asunto(s)
Linfoma de Burkitt , Enfermedades Renales , Masculino , Humanos , Niño , Preescolar , Femenino , Estudios Retrospectivos , Riñón/diagnóstico por imagen , Riñón/patología , Linfoma de Burkitt/patología , Enfermedades Renales/patología , Nefrectomía
11.
Apoptosis ; 17(8): 832-41, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22484481

RESUMEN

Juglanthraquinone C (1,5-dihydroxy-9,10-anthraquinone-3-carboxylic acid, JC), a naturally occurring anthraquinone isolated from the stem bark of Juglans mandshurica, shows strong cytotoxicity in various human cancer cells in vitro. Here, we first performed a structure-activity relationship study of six anthraquinone compounds (JC, rhein, emodin, aloe-emodin, physcion and chrysophanol) to exploit the relationship between their structural features and activity. The results showed that JC exhibited the strongest cytotoxicity of all compounds evaluated. Next, we used JC to treat several human cancer cell lines and found that JC showed an inhibitory effect on cell viability in dose-dependent (2.5-10 µg/ml JC) and time-dependent (24-48 h) manners. Importantly, the inhibitory effect of JC on HepG2 (human hepatocellular carcinoma) cells was more significant as shown by an IC(50) value of 9 ± 1.4 µg/ml, and 36 ± 1.2 µg/ml in L02 (human normal liver) cells. Further study suggested that JC-induced inhibition HepG2 cell proliferation was associated with S phase arrest, decreased protein expression of proliferation marker Ki67, cyclin A and cyclin-dependent kinase (CDK) 2, and increased expression of cyclin E and CDK inhibitory protein Cip1/p21. In addition, JC significantly triggered apoptosis in HepG2 cells, which was characterized by increased chromatin condensation and DNA fragmentation, activation of caspase-9 and -3, and induction of a higher Bax/Bcl2 ratio. Collectively, our study demonstrated that JC can efficiently inhibit proliferation and induce apoptosis in HepG2 cells.


Asunto(s)
Antraquinonas/farmacología , Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Medicamentos Herbarios Chinos/farmacología , Juglans/química , Puntos de Control de la Fase S del Ciclo Celular/efectos de los fármacos , Caspasa 3/metabolismo , Caspasa 9/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Activación Enzimática , Células Hep G2 , Humanos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Relación Estructura-Actividad , Proteína X Asociada a bcl-2/metabolismo
12.
Bioorg Med Chem Lett ; 22(1): 313-8, 2012 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-22142540

RESUMEN

The synthesis of nine bivalent lactosides (based on ditriazoles, diamides, a glycocyclophane and an acyclic analogue of the glycocyclophane) and one monovalent lactosyl triazole facilitated the assessment of the sensitivity of plant/animal lectins to this type of ligand display. The inhibitory potency of the compounds was determined in two assays of increasing biorelevance. These were solid-phase and cell binding set-ups. Hereby, the ability of the compounds to inhibit the binding of two plant agglutinins and the entire set of adhesion/growth-regulatory galectins from one organism (chicken) to a glycoprotein or to cell surfaces was systematically evaluated. Differential sensitivities were detected between plant and animal lectins and also between distinct galectin forms within the chicken series. Two of the bivalent probes can be considered as sensors for interlectin differences. Most pronounced were the selectivities of N-glycosyl 1,2,3-triazole derivatives for the chimera-type galectin and its proteolytically truncated version.


Asunto(s)
Química Farmacéutica/métodos , Glicósidos/química , Lectinas/química , Aglutininas/química , Animales , Sitios de Unión , Membrana Celular/química , Pollos , Relación Dosis-Respuesta a Droga , Diseño de Fármacos , Galectinas/química , Glicoproteínas/química , Cinética , Ligandos , Modelos Químicos , Lectinas de Plantas/química , Sensibilidad y Especificidad , Triazoles/química
13.
Org Biomol Chem ; 10(34): 6893-907, 2012 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-22842468

RESUMEN

The emerging functional versatility of cellular glycans makes research on the design of synthetic inhibitors a timely topic. In detail, the combination of ligand (or headgroup or contact site) structure with spatial parameters that depend on topological and geometrical factors underlies the physiological selectivity of glycan-protein (lectin) recognition. We herein tested a panel of bi-, tri- and tetravalent compounds against two plant agglutinins and adhesion/growth-regulatory lectins (galectins). In addition, we examined the impact of headgroup tailoring (converting lactose to 2'-fucosyllactose) in combination with valency increase in two assay types of increasing biorelevance (from solid-phase binding to cell binding). Compounds were prepared using copper-catalysed azide alkyne cycloaddition from peracetylated lactosyl or 2'-fucosyllactosyl azides. Significant inhibition was achieved for the plant toxin with a tetravalent compound. Different levels of sensitivity were noted for the three groups of the galectin family. The headgroup extension to 2'-fucosyllactose led to a selectivity gain, especially for the chimera-type galectin-3. Valency increase established discrimination against the homodimeric proteins, whereas the combination of valency with the headgroup extension led to discrimination against the tandem-repeat-type galectin-8 for chicken galectins but not human galectins-3 and -4. Thus, detailed structure-activity profiling of glycoclusters combined with suitably modifying the contact site for the targeted lectin will help minimize cross-reactivity among this class of closely related proteins.


Asunto(s)
Lectinas/antagonistas & inhibidores , Polisacáridos/síntesis química , Polisacáridos/farmacología , Animales , Conformación de Carbohidratos , Técnicas de Química Sintética , Pollos , Galectinas/antagonistas & inhibidores , Humanos , Modelos Moleculares , Lectinas de Plantas/antagonistas & inhibidores , Polisacáridos/química , Relación Estructura-Actividad , Especificidad por Sustrato
14.
Org Biomol Chem ; 10(15): 2923-7, 2012 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-22286559

RESUMEN

A series of N-substituted ε-hexonolactams have been designed and prepared by a concise route with a tandem ring-expansion reaction as the key step. Some of the N-substituted ε-hexonolactams show better enhancements to N370S mutant ß-glucocerebrosidase activity than NB-DNJ and NN-DNJ. Both the experimental results and computational studies highlight the importance of the carbonyl group for stabilizing protein folds in the mutant enzyme. The structure-activity relationships are also discussed. These novel N-alkylated iminosugars are promising pharmacological chaperones for the treatment of N370S mutant Gaucher disease.


Asunto(s)
Activadores de Enzimas/síntesis química , Enfermedad de Gaucher/tratamiento farmacológico , Glucosilceramidasa/metabolismo , Iminoazúcares/síntesis química , Lactamas/síntesis química , 1-Desoxinojirimicina/análogos & derivados , 1-Desoxinojirimicina/farmacología , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Activación Enzimática , Activadores de Enzimas/farmacología , Enfermedad de Gaucher/enzimología , Enfermedad de Gaucher/patología , Glucosilceramidasa/química , Glucosilceramidasa/genética , Humanos , Iminoazúcares/farmacología , Cinética , Lactamas/farmacología , Modelos Moleculares , Mutación , Pliegue de Proteína , Relación Estructura-Actividad
15.
Int J Mol Sci ; 13(12): 17185-209, 2012 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-23242155

RESUMEN

Insulin-like growth factor 1 receptor (IGF1R) is an attractive drug target for cancer therapy and research on IGF1R inhibitors has had success in clinical trials. A particular challenge in the development of specific IGF1R inhibitors is interference from insulin receptor (IR), which has a nearly identical sequence. A few potent inhibitors that are selective for IGF1R have been discovered experimentally with the aid of computational methods. However, studies on the rapid identification of IGF1R-selective inhibitors using virtual screening and confidence-level inspections of ligands that show different interactions with IGF1R and IR in docking analysis are rare. In this study, we established virtual screening and binding-mode prediction workflows based on benchmark results of IGF1R and several kinase receptors with IGF1R-like structures. We used comprehensive analysis of the known complexes of IGF1R and IR with their binding ligands to screen specific IGF1R inhibitors. Using these workflows, 17 of 139,735 compounds in the NCI (National Cancer Institute) database were identified as potential specific inhibitors of IGF1R. Calculations of the potential of mean force (PMF) with GROMACS were further conducted for three of the identified compounds to assess their binding affinity differences towards IGF1R and IR.


Asunto(s)
Antineoplásicos/química , Bases de Datos de Compuestos Químicos , Simulación del Acoplamiento Molecular , Proteínas de Neoplasias/antagonistas & inhibidores , Receptores de Somatomedina/antagonistas & inhibidores , Ensayos de Selección de Medicamentos Antitumorales , Humanos , National Cancer Institute (U.S.) , Proteínas de Neoplasias/química , Receptor IGF Tipo 1 , Receptores de Somatomedina/química , Estados Unidos
16.
Sci Rep ; 12(1): 7118, 2022 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-35504960

RESUMEN

Natural killer/T-cell lymphoma (NKTCL) in children and adolescents is a rare type of T/NK cell neoplasms. The aim of the present study was to analyze the clinicopathological and genetic features of this rare entity of lymphoma. We evaluated the clinical, histopathological and molecular features of 22 young people with NKTCL, including 15 males and 7 females, with a median age of 15 years. The results revealed that the nasal site was the most involved region while non-nasal sites were observed in 27.3% out of all cases. The tumor cells were composed of small­sized to large cells and 19 (86.4%) cases exhibited coagulative necrosis. The neoplastic cells in all patients were positive for CD3 and the cytotoxic markers. Nineteen (86.4%) cases were positive for CD56. Reduced expression of CD5 was observed in all available cases. CD30 was heterogeneously expressed in 15 (75.0%) cases. All 22 patients were EBV positive. Seven (36.8%) out of all the 19 patients during the follow-up died of the disease, and the median follow­up period was 44 months. Moreover, patients treated with radiotherapy/chemotherapy showed significantly inferior OS compared with the untreated patients. High mutation frequencies were detected including KMT2C (5/5), MST1 (5/5), HLA-A (3/5) and BCL11A (3/5), which involved in modifications, tumor suppression and immune surveillance. These results suggest that NKTCL in children and adolescents exhibits histopathological and immunohistochemical features similar to the cases in adults. Active treatment is necessary after the diagnosis of NKTCL is confirmed. Furthermore, genetic analyse may provide a deep understanding of this rare disease.


Asunto(s)
Linfoma Extranodal de Células NK-T , Células T Asesinas Naturales , Adolescente , Adulto , Niño , Femenino , Humanos , Antígeno Ki-1 , Células Asesinas Naturales/patología , Linfoma Extranodal de Células NK-T/diagnóstico , Masculino , Células T Asesinas Naturales/patología , Estudios Retrospectivos
17.
Quant Imaging Med Surg ; 12(1): 384-394, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34993087

RESUMEN

BACKGROUND: The present study aimed to use magnetic resonance (MR) to explore the dynamic changes of the ischiofemoral space (IFS) under the triaxial motion of the hip joint and verify the clinical test mechanism for ischiofemoral impingement (IFI). METHODS: A prospective design was used to screen 37 patients with clinically confirmed IFI, which included a total of 67 lateral hips, and 39 healthy controls with a total of 69 lateral hips. A dynamic MR examination was performed in positions designed by a simulated IFI test (adduction, adduction with 30° external rotation, 30° internal rotation, supine with 30° flexion, and prone with 30° backward extension). The IFS (mm) and quadratus femoris space (QFS, mm) were measured in different positions. All the data were evaluated independently by three musculoskeletal radiologists. The differences between the two groups were compared using the two-tailed t-test. RESULTS: The IFS and QFS in the case group were smaller than those in the control group. The IFS and QFS were significantly reduced in the prone with backward extension and adduction with external rotation positions of the hip. The correlation coefficients of the IFI test and long-stride walking (LSW) test were -0.621 and -0.715 for IFS and -0.653 and -0.696 for QFS, respectively. CONCLUSIONS: In this study, the mechanism of the IFI-specific clinical examination (IFI and LSW tests) was verified by triaxial dynamic MR imaging of the hip joint, which provided a dynamic imaging basis for the clinical application of the IFI-specific impingement test. The IFI impingement test can be used as a specific clinical test for IFI screening.

18.
Int J Biol Macromol ; 222(Pt A): 90-100, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36165870

RESUMEN

The structural characteristics and immunoregulatory activities of neutral heteropolysaccharide (AVRP-N) separated from the roots of Apocynum venetum L. were extensively investigated. The results showed that the weight average molecular mass (Mw) of AVRP-N was 6.430 × 103 Da. Moreover, the backbone is composed of natural acetylated (1 â†’ 4)-ß-D-Man and (1 â†’ 5)-α-L-Ara domains. The mannan is composed of →4)-ß-D-Manp-(1→, →4)-ß-D-Glcp-(1→, and the terminal group α-D-Galp-(1→ attached to →4,6)-ß-D-Manp-(1→ at O-6. Araban is composed of →5)-α-L-Araf-(1→; the terminal group α-L-Araf-(1→attached to→2,3,5)-α-L-Araf-(1→ at O-2, O-3 and →3,5)-α-L-Araf-(1→ at O-3. In addition, the senior structure shows that AVRP-N has a triple-helix conformation. Furthermore, AVRP-N exhibited immunomodulatory effects, which could significantly regulate the proliferation of mouse splenic lymphocytes by enhancing the secretion of the cytokines (IFN-γ, IL-2, IL-4, and IL-10). Our results provide new structural and immunoregulatory information for natural polysaccharides derived from Apocynum venetum L.


Asunto(s)
Apocynum , Ratones , Animales , Polisacáridos/farmacología , Polisacáridos/química , Mananos , Raíces de Plantas , Peso Molecular
19.
Front Oncol ; 12: 892510, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35785157

RESUMEN

Objective: This study aimed to establish a prognostic stratified model of chemotherapy-based comprehensive treatment for patients with locoregional recurrent nasopharyngeal carcinoma (lrNPC), to help individualized treatment decision-making. Materials and Methods: This study retrospectively reviewed patients with lrNPC who received chemotherapy-based comprehensive treatment from January 1, 2010, to December 31, 2018. A total of 422 eligible patients were divided into test (n = 338) and validation (n = 84) cohorts. A LASSO cox regression model was used to identify significant prognostic factors for overall survival (OS) in the test cohort. A nomogram was then developed based on a combined consideration of clinically meaningful prognostic factors and statistically significant prognostic factors. The performance of the nomogram was assessed with Harrell's concordance index (C-index) and calibration plots. Results: Five significant factors were identified: age, albumin (ALB), T stage after recurrent (rT), neutrophil to lymphocyte ratio (NLR), and systematic immune-inflammation index (SII). The nomogram was established with these five factors. C-index was 0.636 in the test cohort and 0.610 in the validation cohort. The calibration curves for the OS rate at 3, and 5 years showed an excellent agreement in both cohorts. In addition, the corresponding risk classification system successfully classified patients into low- and high-risk groups and performed well in stratification (P < 0.001). Conclusions: The nomogram shows well prognostic performance for lrNPC patients receiving chemotherapy-based comprehensive treatment.

20.
J Org Chem ; 76(7): 2001-9, 2011 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-21375224

RESUMEN

A versatile and concise synthesis of N-alkylated 1,4-dideoxy-1,4-imino-D-arabinitol and 1,4-dideoxy-1,4-imino-L-xylitol derivatives is described. These were prepared using pseudohemiketal lactams as key intermediates, which in turn were obtained from sucrose. The key intermediates were prepared by a diastereospecific tandem reaction which facilitated the introduction of various substituents on the nitrogen atom of the iminosugars.


Asunto(s)
Lactamas/química , Alcoholes del Azúcar/síntesis química , Xilitol/análogos & derivados , Alquilación , Arabinosa , Iminofuranosas/síntesis química , Iminofuranosas/química , Espectroscopía de Resonancia Magnética , Estructura Molecular , Estereoisomerismo , Alcoholes del Azúcar/química , Xilitol/síntesis química , Xilitol/química
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