Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
1.
Commun Biol ; 7(1): 824, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38971948

RESUMO

The expression dysregulation of microRNAs (miRNA) has been widely reported during cancer development, however, the underling mechanism remains largely unanswered. In the present work, we performed a systematic integrative study for genome-wide DNA methylation, copy number variation and miRNA expression data to identify mechanisms underlying miRNA dysregulation in lower grade glioma. We identify 719 miRNAs whose expression was associated with alterations of copy number variation or promoter methylation. Integrative multi-omics analysis revealed four subtypes with differing prognoses. These glioma subtypes exhibited distinct immune-related characteristics as well as clinical and genetic features. By construction of a miRNA regulatory network, we identified candidate miRNAs associated with immune evasion and response to immunotherapy. Finally, eight prognosis related miRNAs were validated to promote cell migration, invasion and proliferation through in vitro experiments. Our study reveals the crosstalk among DNA methylation, copy number variation and miRNA expression for immune regulation in glioma, and could have important implications for patient stratification and development of biomarkers for immunotherapy approaches.


Assuntos
Neoplasias Encefálicas , Variações do Número de Cópias de DNA , Metilação de DNA , Regulação Neoplásica da Expressão Gênica , Glioma , MicroRNAs , Humanos , Glioma/genética , Glioma/imunologia , Glioma/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/patologia , Epigenômica , Genômica , Redes Reguladoras de Genes , Linhagem Celular Tumoral , Evasão da Resposta Imune/genética , Epigênese Genética , Feminino , Masculino , Prognóstico , Gradação de Tumores
2.
Bioorg Chem ; 143: 106987, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38039927

RESUMO

Secreted proteins play critical roles in regulating immune responses, exerting cytotoxic effects on tumor cells, promoting inflammatory processes, and influencing cellular metabolism. Deciphering the intricate relationship between the heterogeneity of secreted proteins and their transcriptional states is pivotal in the study of cellular heterogeneity. Here we proposed a cell-antibody conjugate-based sequencing methodology (Cellab-seq) for joint characterization of secreted proteins and transcriptome. Cellab-seq utilizes a chemoenzymatic strategy to construct cell-antibody conjugates, which enables the capture of secreted proteins and their signal transduction with the incorporation of barcode detection antibodies. We applied Cellab-seq to investigate how gene expression influences the activity of secreted proteins in NK cells. Altogether, this strategy facilitates a nuanced understanding of cellular dynamics under diverse physiological conditions, ultimately contributing to the prevention, diagnosis and treatment of diseases.


Assuntos
Células Matadoras Naturais , Transcriptoma
3.
Adv Sci (Weinh) ; 10(33): e2203987, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37849233

RESUMO

Albeit the majority of eukaryotic genomes can be pervasively transcribed to a diverse population of lncRNAs and various subtypes of lncRNA are discovered. However, the genome-wide study of miRNA-derived lncRNAs is still lacking. Here, it is reported that over 800 miRNA gene-originated lncRNAs (molncRNAs) are generated from miRNA loci. One of them, molnc-301b from miR-301b and miR-130b, functions as an "RNA decoy" to facilitate dissociation of the chromatin remodeling protein SMARCA5 from chromatin and thereby sequester transcription and mRNA translation. Specifically, molnc-301b attenuates erythropoiesis by mitigating the transcription of erythropoietic and translation-associated genes, such as GATA1 and FOS. In addition, a useful and powerful CRISPR screen platform to characterize the biological functions of molncRNAs at large-scale and single-cell levels is established and 29 functional molncRNAs in hematopoietic cells are identified. Collectively, the focus is on miRNA-derived lncRNAs, deciphering their landscape during normal hematopoiesis, and comprehensively evaluating their potential roles.


Assuntos
MicroRNAs , RNA Longo não Codificante , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Estudo de Associação Genômica Ampla , Fatores de Transcrição/genética
4.
Ann Med ; 55(1): 2227425, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37387123

RESUMO

BACKGROUND: Amyloid light chain (AL) amyloidosis is the most common systemic amyloidosis. The objective of this scoping review was to map the available literature on the diagnosis of AL amyloidosis in China. MATERIALS AND METHODS: The published academic papers related to the diagnosis of AL amyloidosis were screened from 1 January 2000 to 15 September 2021. Chinese patients who have suspected AL amyloidosis were included. The included studies were categorized into accuracy studies and descriptive studies based on if the studies supplied the diagnostic accuracy data or not. The information on the diagnostic methods reported by included studies was synthesized. RESULTS: Forty-three articles were included for the final scoping review, with 31 belonging to descriptive studies and 12 having information on diagnostic accuracy. Although cardiac involvement was second top in Chinese patients with AL amyloidosis, a cardiac biopsy was rare. Next, we found light chain classification and monoclonal (M-) protein identification were essential methods for the diagnosis of AL amyloidosis in China. In addition, some combined tests (e.g. immunohistochemistry and serum free light chain, immunohistochemistry and immunofixation electrophoresis, and serum free light chain and immunofixation electrophoresis) can increase the sensitivity of the diagnosis. Finally, several adjuvant methods (e.g. Imaging, N-terminal-pro hormone BNP, and brain natriuretic peptide test) were important for AL amyloidosis diagnosis. CONCLUSION: This scoping review details the characteristics and results of the recently published studies on diagnosing AL Amyloidosis in China. Biopsy is the most important method for AL Amyloidosis diagnosis in China. In addition, combined tests and some adjuvant methods played essential roles in the diagnosis. Further research is required to determine an acceptable and feasible diagnostic algorithm after symptom onset. REGISTRATION: INPLASY2022100096KEY MESSAGESThis scoping review details the characteristics and results of the recently published studies on diagnosing Amyloid light chain (AL) Amyloidosis in China.Biopsy is the most important method for AL Amyloidosis diagnosis in China.Combined tests and some adjuvant methods played essential roles in the diagnosis.


Assuntos
Amiloidose , Amiloidose de Cadeia Leve de Imunoglobulina , Humanos , Adjuvantes Imunológicos , Amiloidose/diagnóstico , População do Leste Asiático , Amiloidose de Cadeia Leve de Imunoglobulina/diagnóstico
5.
ACS Pharmacol Transl Sci ; 6(5): 702-709, 2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37200809

RESUMO

5-Fluorouracil and 5-fluorouracil-based prodrugs have been used clinically for decades to treat cancer. Their anticancer effects are most prominently ascribed to inhibition of thymidylate synthase (TS) by metabolite 5-fluoro-2'-deoxyuridine 5'-monophosphate (FdUMP). However, 5-fluorouracil and FdUMP are subject to numerous unfavorable metabolic events that can drive undesired systemic toxicity. Our previous research on antiviral nucleotides suggested that substitution at the nucleoside 5'-carbon imposes conformational restrictions on the corresponding nucleoside monophosphates, rendering them poor substrates for productive intracellular conversion to viral polymerase-inhibiting triphosphate metabolites. Accordingly, we hypothesized that 5'-substituted analogs of FdUMP, which is uniquely active at the monophosphate stage, would inhibit TS while preventing undesirable metabolism. Free energy perturbation-derived relative binding energy calculations suggested that 5'(R)-CH3 and 5'(S)-CF3 FdUMP analogs would maintain TS potency. Herein, we report our computational design strategy, synthesis of 5'-substituted FdUMP analogs, and pharmacological assessment of TS inhibitory activity.

6.
Nat Cell Biol ; 24(8): 1278-1290, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35927451

RESUMO

METTL3 encodes the predominant catalytic enzyme to promote m6A methylation in nucleus. Recently, accumulating evidence has shown the expression of METTL3 in cytoplasm, but its function is not fully understood. Here we demonstrated an m6A-independent mechanism for METTL3 to promote tumour progression. In gastric cancer, METTL3 could not only facilitate cancer progression via m6A modification, but also bind to numerous non-m6A-modified mRNAs, suggesting an unexpected role of METTL3. Mechanistically, cytoplasm-anchored METTL3 interacted with PABPC1 to stabilize its association with cap-binding complex eIF4F, which preferentially promoted the translation of epigenetic factors without m6A modification. Clinical investigation showed that cytoplasmic distributed METTL3 was highly correlated with gastric cancer progression, and this finding could be expanded to prostate cancer. Therefore, the cytoplasmic METTL3 enhances the translation of epigenetic mRNAs, thus serving as an oncogenic driver in cancer progression, and METTL3 subcellular distribution can assist diagnosis and predict prognosis for patients with cancer.


Assuntos
Metiltransferases , Neoplasias Gástricas , Adenosina/metabolismo , Carcinogênese/genética , Epigênese Genética , Humanos , Masculino , Metiltransferases/genética , Metiltransferases/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Neoplasias Gástricas/genética
7.
Biochim Biophys Acta Mol Basis Dis ; 1868(11): 166508, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35905940

RESUMO

Sarcopenia and obese sarcopenia are increasingly prevalent chronic diseases with multifactorial pathogenesis, and no approved therapeutic drug to date. In the established sarcopenic mice models, muscle weakness, ectopic lipid deposition, and inflammatory responses in both serum and gastrocnemius muscle were observed, which were even deteriorated in obese sarcopenic models. With metformin intervention for 5 months, metformin exhibited benefits and restoring effects on gastrocnemius muscle of sarcopenic mice, but less effective on that of obese sarcopenic mice, as reflected in the increased percentage of muscle mass and enlarged fiber cross-sectional area, enhanced grip strength and exercise capacities, as well as the ameliorated ectopic lipid deposition and partially restored level of TNF-α, IL-1ß, IL-6, MCP-1 and IL-1α, which may be via the activation of phospho-AMPKα (Thr172). The significant up-regulated mRNA and protein level of lipolysis related proteins like hormone-sensitive lipase (HSL) and adipose triglyceride lipase (ATGL) may contribute to the ameliorated ectopic lipid deposition with metformin intervention. The uptake of free fatty acid may be also inhibited in obese sarcopenic mice with metformin administration, as reflected in down-regulated mRNA and protein level of fatty acid transporter CD36. Furthermore, NF-κB signaling pathway was involved in the anti-inflammatory effect of metformin. These findings suggest that metformin treatment may be conducive to the prevention of age-related sarcopenia by regulating lipid metabolism in skeletal muscle, i.e. enhanced lipolysis and attenuated hyper-inflammatory responses, which may be AMPK-dependent processes. Moreover, high-fat diet would aggravate the damage to ageing in skeletal muscles and reduced their reactivity to metformin.


Assuntos
Metformina , Sarcopenia , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Anti-Inflamatórios , Ácidos Graxos não Esterificados/metabolismo , Interleucina-6/metabolismo , Lipase/metabolismo , Metformina/farmacologia , Metformina/uso terapêutico , Camundongos , Camundongos Obesos , Músculo Esquelético/metabolismo , NF-kappa B/metabolismo , Obesidade/complicações , Obesidade/tratamento farmacológico , Obesidade/metabolismo , RNA Mensageiro/metabolismo , Sarcopenia/tratamento farmacológico , Sarcopenia/etiologia , Esterol Esterase , Fator de Necrose Tumoral alfa/metabolismo
8.
Cancer Cell Int ; 22(1): 222, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35788237

RESUMO

BACKGROUND: Intravenous daratumumab (DARA IV) has been increasingly used in the treatment of amyloid light-chain (AL) amyloidosis. However, the outcomes for patients administered with DARA IV have not been aggregated. The objective of this systematic review and meta-analysis was to investigate the efficacy and safety of DARA IV for AL amyloidosis. METHODS: We searched Medline, EMBASE, Cochrane Library and Web of Science up to 17 June 2021. Response rates and survival rates, and the corresponding 95% confidence intervals (CIs) were pooled and calculated using a fixed-effects model. RESULTS: Thirty studies (5 cohort studies and 25 single-arm studies) with 997 patients were included. In patients receiving DARA IV-based treatments, very good partial response or better response rate, complete response rate, very good partial response rate, partial response rate and overall response rate were 66% (95% CI, 62-69%), 30% (95% CI, 23-36%), 40% (95% CI, 33-46%), 17% (95% CI, 14-21%), and 77% (95% CI, 73-80%), respectively. Cardiac and renal responses were 41% (95% CI, 34-49%) and 43% (95% CI, 32-54%), respectively. 58% (95% CI, 49-66%) of patients achieved PFS one year or longer. 2.5% (range, 1-10.0%) of patients experienced grade 3 or 4 adverse events, of which the most common adverse event was lymphocytopenia (range, 13.6-25.0%). CONCLUSION: This study supports the efficacy and safety of DARA IV for the treatment of patients with AL amyloidosis.

9.
Genome Biol ; 22(1): 290, 2021 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-34649616

RESUMO

BACKGROUND: Cellular RNA-binding proteins (RBPs) have multiple roles in post-transcriptional control, and some are shown to bind DNA. However, the global localization and the general chromatin-binding ability of RBPs are not well-characterized and remain undefined in hematopoietic cells. RESULTS: We first provide a full view of RBPs' distribution pattern in the nucleus and screen for chromatin-enriched RBPs (Che-RBPs) in different human cells. Subsequently, by generating ChIP-seq, CLIP-seq, and RNA-seq datasets and conducting combined analysis, the transcriptional regulatory potentials of certain hematopoietic Che-RBPs are predicted. From this analysis, quaking (QKI5) emerges as a potential transcriptional activator during monocytic differentiation. QKI5 is over-represented in gene promoter regions, independent of RNA or transcription factors. Furthermore, DNA-bound QKI5 activates the transcription of several critical monocytic differentiation-associated genes, including CXCL2, IL16, and PTPN6. Finally, we show that the differentiation-promoting activity of QKI5 is largely dependent on CXCL2, irrespective of its RNA-binding capacity. CONCLUSIONS: Our study indicates that Che-RBPs are versatile factors that orchestrate gene expression in different cellular contexts, and identifies QKI5, a classic RBP regulating RNA processing, as a novel transcriptional activator during monocytic differentiation.


Assuntos
Diferenciação Celular/genética , Cromatina/metabolismo , Monócitos/metabolismo , Proteínas de Ligação a RNA/metabolismo , Ativação Transcricional , Linhagem Celular , Quimiocina CXCL2 , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Humanos , Mutação , Regiões Promotoras Genéticas , Proteínas de Ligação a RNA/genética , Transcriptoma
10.
J Pain Res ; 14: 2665-2675, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34483686

RESUMO

PURPOSE: To determine whether the teaching method of seminars combined with case-based learning (CBL) is superior to the traditional lecture-based learning (LBL) for teaching cancer pain in medical oncology internship. METHODS: Sixty medical and nursing interns in the medical oncology department of our hospital were selected between January 2019 and December 2020. Thirty students received traditional LBL instruction as the control group, and 30 students received combined seminars and CBL instruction as the observation group. The teaching evaluation and assessment was performed by theoretical and practical examinations and questionnaires. RESULTS: In the after-class examination, case analysis, clinical practice and overall scores of the observation group were higher than those of the control group (all p < 0.001). Theoretical knowledge scores did not differ significantly between the two groups (p = 0.470). In the questionnaire regarding attitudes towards opioid use, the observation group had better perceptions of using opioids than the control group (all p < 0.01). In the meantime, students in the observation group outperformed the control group in four aspects: self-learning (p < 0.001), analytical and problem-solving (p < 0.001), clinical thinking (p = 0.001), and clinical practice (p = 0.002) abilities all improved, while stimulating learning interest (p = 0.184) and enhancing theoretical knowledge mastery (p = 0.221) were not significantly different from those of the control group. Overall, students in the observation group were more satisfied with the teaching, teaching methods and teacher performances than the control group (all p < 0.001). CONCLUSION: Compared to the LBL, the combination of seminars and CBL is a more effective teaching method for cancer pain management, which is worth further study.

12.
Biomed Res Int ; 2020: 6152925, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32280692

RESUMO

A STRN-ALK fusion protein has been recently identified as a potential therapeutic target in multiple cancers; however, the role of STRN alone in regulating the biological function of hepatocellular carcinoma (HCC) remains unclear. In this study, we firstly detected an overexpression of STRN in HCC tissues compared to that in adjacent nontumour (ANT) tissues through IHC analysis, and the expression level of this protein was positively correlated with lymph node metastasis and TNM stage. In vitro, high expression of STRN was also confirmed in different HCC cell lines, and regulation of STRN expression in Huh7 cells did not significantly affect tumour cell proliferation or apoptosis but was positively correlated with tumour cell invasion and migration capacities. Moreover, both the knockdown and overexpression of STRN in Huh7 cells can lead to cell morphological changes that are accompanied with an alteration of epithelial-mesenchymal transition (EMT) molecular markers E-cadherin and Vimentin. Finally, STRN was further proved to be negatively related to E-cadherin expression but positively related to Vimentin expression in human HCC tissue samples. Taken together, STRN is upregulated in HCC and acts as a tumour promoter regulating cell invasion and migration through facilitating the EMT process.


Assuntos
Apoptose , Proteínas de Ligação a Calmodulina/genética , Carcinoma Hepatocelular/genética , Proliferação de Células , Transição Epitelial-Mesenquimal/genética , Neoplasias Hepáticas/genética , Proteínas de Membrana/genética , Proteínas do Tecido Nervoso/genética , Antígenos CD/genética , Antígenos CD/metabolismo , Biomarcadores Tumorais , Caderinas/genética , Caderinas/metabolismo , Proteínas de Ligação a Calmodulina/metabolismo , Carcinoma Hepatocelular/diagnóstico , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Marcadores Genéticos , Células Hep G2 , Humanos , Neoplasias Hepáticas/diagnóstico , Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Vimentina/genética , Vimentina/metabolismo
13.
J Exp Clin Cancer Res ; 37(1): 65, 2018 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-29566713

RESUMO

BACKGROUND: PHD-finger domain protein 5A (PHF5A) is a highly conserved small transcriptional regulator also involved in pre-mRNA splicing; however, its biological functions and molecular mechanisms in non-small cell lung cancer (NSCLC) have not yet been investigated. The purpose of this study was to determine the functional relevance and therapeutic potential of PHF5A in lung adenocarcinoma (LAC). METHODS: The expression of PHF5A in LAC tissues and adjacent non-tumor (ANT) tissues was investigated using immunohistochemistry of a tissue microarray, qRT-PCR, western blot and bioinformatics. The function of PHF5A was determined using several in vitro assays and also in vivo assay by lentiviral vector-mediated PHF5A depletion in LAC cell lines. RESULTS: PHF5A was highly upregulated in LAC tissues compared with the ANT counterparts, and closely associated with tumor progression and poor patient prognosis. These results were further confirmed by findings of the TCGA database. Moreover, functional studies demonstrated that PHF5A knockdown not only resulted in reduced cell proliferation, increased cell apoptosis, and cell cycle arrest, but also suppressed migration and invasion in LAC cells. PHF5A silencing was also found to inhibit LAC tumor growth in nude mice. Microarray and bioinformatics analyses revealed that PHF5A depletion led to dysregulation of multiple tumor signaling pathways; selected factors in key signaling pathways were verified in vitro. CONCLUSIONS: The data suggest for the first time that PHF5A is an oncoprotein that contributes to LAC progression by regulating multiple signaling pathways, and may constitute a prognostic factor and potential new therapeutic target in NSCLC.


Assuntos
Adenocarcinoma de Pulmão/metabolismo , Biomarcadores Tumorais , Proteínas de Transporte/metabolismo , Proteínas Oncogênicas/metabolismo , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/mortalidade , Adenocarcinoma de Pulmão/patologia , Adulto , Idoso , Animais , Apoptose/genética , Proteínas de Transporte/genética , Linhagem Celular Tumoral , Proliferação de Células , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Biologia Computacional , Modelos Animais de Doenças , Progressão da Doença , Feminino , Expressão Gênica , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Redes Reguladoras de Genes , Xenoenxertos , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Gradação de Tumores , Metástase Neoplásica , Estadiamento de Neoplasias , Proteínas Oncogênicas/genética , Proteínas de Ligação a RNA , Análise Serial de Tecidos , Transativadores
14.
Drug Chem Toxicol ; 39(2): 167-73, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26154125

RESUMO

Paraquat (PQ) is a widely used herbicide associated with a high mortality rate, yet, there are no effective treatments for PQ poisoning. PQ may damage alveolar type II cells leading to moderate to severe acute respiratory distress syndrome (ARDS). The present study was undertaken to show that PQ causes alveolar type II (A549) cell death and to evaluate whether chloroquine (CQ) can protect A549 cells against PQ-induced cell death. The results showed that high concentrations of PQ resulted in toxicity, as indicated by a decrease in cell viability. More importantly, for the first time, CQ was found to improve cell viability of PQ treated A549 cells. Moreover, our data demonstrated that CQ increased lysosome-associated membrane protein-1, lysosome-associated membrane protein-2 and light chain-3 expressions, suggesting that the mechanism by which CQ rescues PQ-induced cytotoxicity may be through protection of the lysosomal membrane or up-regulation of autophagy. In conclusion, our study indicates that CQ may be used as a potential drug to rescue PQ-induced ARDS.


Assuntos
Autofagia/efeitos dos fármacos , Cloroquina/farmacologia , Células Epiteliais/efeitos dos fármacos , Herbicidas/toxicidade , Paraquat/toxicidade , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Humanos , Membranas Intracelulares/efeitos dos fármacos , Membranas Intracelulares/metabolismo , Proteínas de Membrana Lisossomal/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Lisossomos/patologia
15.
Bioconjug Chem ; 16(5): 1126-32, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16173789

RESUMO

(99m)Technetium-labeled diethylenetriamine pentaacetic acid-polyethylene glycol-folate (DTPA-PEG-folate) was synthesized and tested as a radiopharmaceutical agent, which targeted the lymphatic system with metastatic tumor. Folic acid was reacted with H2N-PEG-NH2 to yield H2N-PEG-folate. After purification by anion-exchange chromatography, the product was reacted with cyclic DTPA. By removal of unreacted DTPA by size-exclusion chromatography, DTPA-PEG-Folate was obtained. Fluorescein-5-isothiocyanate (FITC)-labeled DTPA-PEG-folate and DTPA-PEG-OCH3 were prepared via a dicyclohexylcarbodiimide-mediated coupling. In vitro competitive binding test showed that the uptake of [125I] folic acid was inhibited by DTPA-PEG-folate and the 50% inhibitory concentration was 4.37 pmol/L (R2 = 0.9922). The relative affinity of DTPA-PEG-FITC was 0.18 for human folate receptor comparing with folic acid. In cultured tumor cells, uptake of fluorescence-labeled DTPA-PEG-folate was found to increase significantly in folate-deficient medium compared with that of untargeted DTPA-PEG-OCH3 and FITC-ethylenediamine. The competition with free folic acid blocked the cell uptake of DTPA-PEG-folate. These results confirmed the DTPA-PEG-folate entered into KB cells through the folate receptor endocytosis pathway in vitro. The radiolabeled yield of [(99m)Tc] DTPA-PEG-folate was in excess of 98%, and specific activities of 7.4 kBq (0.2 microCi/microg) were achieved. After subcutaneous injection, [(99m)Tc] DTPA-PEG-folate exhibited an initial increase and successive decline of accumulation in popliteal nodes in normal Wistar rats. Expect for the kidney, uptake by other tissues was rather low. In a normal rabbit imagine study, the lymphatic vessels were readily visualized by single-photon-emission computed tomography following subcutaneous injection of [(99m)Tc] DTPA-PEG-folate. In conclusion, the [(99m)Tc] DTPA-PEG-folate conjugate may have a potential as a lymphatic tumor-targeted radiopharmaceutical.


Assuntos
Ácido Fólico/química , Ácido Fólico/farmacologia , Ácido Pentético/química , Polietilenoglicóis/química , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/farmacologia , Tecnécio/química , Animais , Linhagem Celular Tumoral , Cromatografia em Gel , Cromatografia por Troca Iônica , Fluoresceína-5-Isotiocianato/química , Ácido Fólico/síntese química , Humanos , Microscopia de Fluorescência , Coelhos , Ratos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA