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1.
J Cancer ; 15(12): 3724-3737, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38911385

RESUMEN

Background: Colorectal cancer (CRC) ranks third in terms of cancer incidence and fourth in terms of cancer-related deaths worldwide. Identifying potential biomarkers of CRC is crucial for treatment and drug development. Methods: In this study, we established a C57B/6N mouse model of colon carcinogenesis using azoxymethane-dextran sodium sulfate (AOM-DSS) treatment for 14 weeks to identify proteins associated with colon cancer. An isobaric tag for relative and absolute quantitation (iTRAQ)-based proteomic analysis was conducted on the cell membrane components enriched in the colonic mucosa. Additionally, tumor tissues and adjacent normal colon tissues were collected from patients with colon cancer for comparative protein and metabolite analyses. Results: In total, 74 differentially expressed proteins were identified in the tumor tissue samples from AOM/DSS-treated mice compared to both the adjacent tissue samples from AOM/DSS-treated mice and tissue samples from saline-treated control mice. Bioinformatics analysis revealed eight downregulated proteins enriched in the branched-chain amino acids pathway (valine, leucine, and isoleucine degradation). Moreover, these proteins are already known to be associated with the survival rate of patients with cancer. Targeted metabolomics showed increased levels of valine, leucine, and isoleucine in tumor tissues compared to those in adjacent normal tissues in patients with colon cancer. Furthermore, a real-time PCR experiment demonstrated that Aldehyde dehydrogenase, mitochondrial (short protein name ALDH2, gene name Aldh2) and Hydroxyacyl-coenzyme A dehydrogenase, mitochondrial (short protein name HCDH, gene name Hadh) (two genes) in the pathway of branched-chain amino acids) were downregulated in patients with colon cancer (colon tumor tissues vs. their adjacent colon tissues). ALDH2 expression was further validated by western blotting in AOM/DSS-treated mouse model and in clinical samples. Conclusion: This study highlighted the inactivation of the branched-chain amino acid degradation pathway in colon cancer and identified ALDH2 and HCDH as potential biomarkers for diagnosing colon cancer and developing new therapeutic strategies.

2.
BMC Infect Dis ; 23(1): 459, 2023 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-37430187

RESUMEN

BACKGROUND: This study aimed to establish an effective ultrasound diagnostic nomogram for benign or malignant lymph nodes in HIV-infected patients. METHODS: The nomogram is based on a retrospective study of 131 HIV-infected patients who underwent ultrasound assess at the Shanghai Public Health Clinical Center from December 2017 to July 2022. The nomogram's predictive accuracy and discriminative ability were determined by concordance index (C-index) and calibration curve analysis. A nomogram combining the lymph node US characteristics were generated based on the multivariate logistic regression results. RESULTS: Predictors contained in the ultrasound diagnostic nomogram included age (OR 1.044 95%CI: 1.014-1.074 P = 0.004), number of enlarged lymph node regions (OR 5.445 95%CI: 1.139-26.029 P = 0.034), and color Doppler flow imaging (CDFI) grades (OR 9.614 95%CI: 1.889-48.930 P = 0.006). The model displayed good discrimination with a C (ROC) of 0.775 and good calibration. CONCLUSIONS: The proposed nomogram may result in more-accurate diagnostic predictions for benign or malignant lymph nodes in patients with HIV infection.


Asunto(s)
Infecciones por VIH , Humanos , Nomogramas , Estudios Retrospectivos , China , Ultrasonografía , Ganglios Linfáticos/diagnóstico por imagen
3.
World J Surg Oncol ; 20(1): 404, 2022 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-36539825

RESUMEN

OBJECTIVE: This investigation aimed to explore the relationship between sarcopenia and severe postoperative complications, relapse-free survival (RFS), and overall survival (OS) in patients with retroperitoneal liposarcoma (RLPS). MATERIAL AND METHODS: This retrospective study included 72 RLPS patients (47 men, 25 women; mean age, 57.49 years, SD 10.92) who had abdominal CT exams. Clinical information was recorded, including RLPS characteristics (histologic subtypes, grade, size), laboratory assessment (ALB, PALB, A/G, Hb, SCr), relapse-free survival, overall survival, and postoperative complications. The relationships between those variables and RFS and OS were analyzed using Cox proportional hazard models. RESULTS: There were 8 severe postoperative complications (Clavien-Dindo grade > 2). The chi-square test showed sarcopenia was associated with severe postoperative complications (P = 0.011). In multivariate analysis, sarcopenia was not associated with relapse-free survival (P = 0.574) and overall survival (P = 0.578). CONCLUSIONS: Sarcopenia predicts worse surgical complications but does not affect relapse-free survival and overall survival.


Asunto(s)
Liposarcoma , Neoplasias Retroperitoneales , Sarcopenia , Masculino , Humanos , Femenino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Neoplasias Retroperitoneales/complicaciones , Neoplasias Retroperitoneales/cirugía , Liposarcoma/complicaciones , Liposarcoma/cirugía , Sarcopenia/complicaciones , Enfermedad Crónica , Complicaciones Posoperatorias
4.
J Clin Transl Res ; 8(5): 339-343, 2022 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-36090013

RESUMEN

Background: There are lacking standard treatment guidelines for aggressive fibromatosis (AF) because of its rarity. Aim: This study aimed to investigate the risk factors for recurrence and survival of abdominal AF after radical surgical resection. Methods: From August 2012 to December 2020, a retrospective analysis was conducted on the clinical data of 69 AF in Shanghai Public Health Clinical Center Affiliated to Fudan University, with the tumor locating either in the abdominal wall or in the abdominal cavity. The main observation end point was progression-free survival time (PFS) and overall survival time (OS). Results: All 69 patients achieved microscopic R0 resection, 10 (14.5%) had local recurrence, and 3 (4.3%) died. The PFS rate after 1, 3, 5, and 10 years was 96.8%, 87.7%, 78.8%, and 78.8%, respectively. The OS rate after 1, 3, 5, and 10 years was 100%, 100%, 92.9%, and 81.3%, respectively. In 10 patients with recurrence, the median recurrence time was 17.6 months. Concomitant familial adenomatous polyposis (FAP) and history of previous recurrence were independent risk factors of post-operative recurrence. Conclusion: After radical surgery of abdominal AF, the local recurrence rate was 15%. Concomitant FAP and a previous history of recurrence were independent risk factors of post-operative recurrence. R0 and a combined organ resection should be performed especially in FAP patients to minimize the recurrence and improve the prognosis. Relevance for Patients: The present study identifies the risk factors of recurrence in AF and suggests R0 resection especially in concomitant FAP patients. A wait-and-see strategy should not be generally implemented and radical surgery will bring clinical benefits to patients with such kind of rare disease.

5.
Front Surg ; 9: 935048, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35903259

RESUMEN

Introduction: Cowden syndrome is a rare autosomal dominant genetic disease associated with PTEN mutation and is mainly shown as systemic multisystem lesions. The incidence of adenocarcinoma of the duodenum with Cowden syndrome in Asian males is rare. We hereby describe the diagnosis, treatment, and prognosis of a patient with duodenal carcinoma and Cowden syndrome. Case Description: A 40-year-old Chinese man was hospitalized because of gastrointestinal hemorrhage and anemia due to infiltrating adenocarcinoma of the descending part of the duodenum. He also had typical signs of Cowden syndrome, such as multiple polyps of the gastrointestinal tract, macrocephaly, papilloma of the tongue, soles hyperkeratosis, and melanosis spots. After the pancreaticoduodenectomy (classic Whipple), the lesions revealed the presence of hamartomatoid polyps, and some of them mutated into non-mucinous adenocarcinoma (80%) and mucinous adenocarcinoma (20%). Further investigation showed a lack of PTEN protein expression in the duodenal neoplasm, and genetic analysis showed the mutation of p.E242fs in PTEN. The patient was followed up for 1 year. There was no appearance of recurrence or distant metastasis. Conclusion: It is suggested that we should pay more attention to the differential diagnosis of duodenal carcinoma combined with gastrointestinal polyps. If multiple gastrointestinal polyps with gastrointestinal bleeding are encountered, Cowden syndrome should be considered, and timely diagnosis and treatment should be implemented.

6.
J Oncol ; 2022: 9514697, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35813857

RESUMEN

Our previous study has indicated that cancer-associated fibroblasts (CAFs) play a crucial role in regulating gemcitabine resistance through transferring exosomal miRNA-106b to cancer cells. Tumor-associated macrophages (TAMs) are recently verified to facilitate gemcitabine resistance. However, the effect of CAFs in regulating TAMs function in pancreatic cancer (PCa) remains unclear. Here, primary CAFs were extracted from tumor tissues of PCa patients, and CAFs-derived exosomes (CAFs-Exo) were acquired and authenticated by transmission electron microscopy, qNano, and western blot analysis. The role of exosomal miRNA-320a in facilitating macrophage M2 polarization was investigated in vitro. We found that CAFs-derived conditioned medium (CM) possessed a higher potential to promote macrophage M2 polarization compared with normal fibroblasts (NFs) or PCa cell-derived CM. Furthermore, CAFs-Exo treatment polarized macrophage to M2 phenotype. miRNA-320a levels were remarkably increased in CAFs-Exo versus NFs-Exo. More important, miRNA-320a could be transferred from CAFs to macrophages through exosomes, and miRNA-320a overexpression in macrophages facilitated its M2 polarization. Functionally, miRNA-320a-overexpressed macrophages facilitated PCa cell proliferation and invasion. CAFs pretreated with miRNA-320a inhibitor reduced miRNA-320a expression in CAFs-Exo and led to decreased M2 macrophage polarization. Finally, we verified that miRNA-320a polarized macrophage to M2 phenotype by regulating PTEN/PI3Kγ signaling. Taken together, the current data demonstrated that CAFs-derived exosomal miRNA-320a facilitated macrophage M2 polarization to accelerate malignant behavior of PCa cells.

7.
World J Surg Oncol ; 20(1): 158, 2022 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-35585636

RESUMEN

BACKGROUND: Most retroperitoneal sarcoma (RPS) operations require combined multi-organ resection, and the proportion of unplanned reoperation is high. However, there are no relevant studies on reoperation for RPS. METHODS: Patients who underwent at least once unplanned reoperation at Shanghai Public Health Clinical Center, Fudan University, China, from August 2009 to December 2021 were retrospectively analyzed. The baseline characteristics, primary surgery, and reoperation information, postoperative complications, and survival were analyzed. RESULTS: A total of 51 patients were included. Among them, 21 (41.2%) were male and 30 (58.8%) were female. The median age was 51 (interquartile range [IQR], 49-63) years. Most (88.3%) had a history of abdominal surgery. Dedifferentiated liposarcoma, well-differentiated liposarcoma, leiomyosarcoma, and others accounted for 50.9%, 21.6%, 15.7%, and 11.8%, respectively. The conditions of the primary operation were as follows: 35 (68.6%) patients achieved complete surgical resection, 48 patients had combined organ resection, and a median of 3 (IQR, 2-4) organs was removed, of which 5 (9.9%) were combined with pancreaticoduodenectomy. The median operative time was 330 (IQR, 245-440) min, and the median estimated blood loss was 1500 (IQR, 500-2600) ml. The median postoperative hospital stay was 42 (IQR, 23-82) days. For reoperation, the most common reasons were bleeding (31.3%), complications related to intestinal anastomosis (27.4%), and intestinal perforation (19.9%). The mortality rate after reoperation was 39.2% (20/51). Twelve (23.5%) patients underwent reoperation at least twice. CONCLUSIONS: Unplanned reoperation among retroperitoneal sarcoma correlates with established measures of surgical quality.


Asunto(s)
Neoplasias Retroperitoneales , Sarcoma , Neoplasias de los Tejidos Blandos , China , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/cirugía , Reoperación , Neoplasias Retroperitoneales/cirugía , Estudios Retrospectivos , Sarcoma/cirugía , Neoplasias de los Tejidos Blandos/cirugía , Tasa de Supervivencia
8.
Antioxid Redox Signal ; 30(16): 1900-1910, 2019 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-30358421

RESUMEN

AIMS: Quantitative imaging of glutathione (GSH) with high spatial and temporal resolution is essential for studying the roles of GSH in redox biology. To study the long-standing question of compartmentalization of GSH, especially its distribution between the nucleus and cytosol, an organelle-targeted quantitative probe is needed. RESULTS: We developed a reversible reaction-based ratiometric fluorescent probe-HaloRT-that can quantitatively measure GSH dynamics with subcellular resolution in real time. Using HaloRT, we quantitatively measured the GSH concentrations in the nucleus and cytosol of HeLa cells and primary hepatocytes under different treatment conditions and found no appreciable concentration gradients between these two organelles. Innovation and Conclusion: We developed the first reversible ratiometric GSH probe that can be universally targeted to any organelle of interest. Taking advantage of this new tool, we provided definitive evidence showing that GSH concentrations are not significantly different between the nucleus and cytosol, challenging the view of nuclear compartmentalization of GSH.


Asunto(s)
Biomarcadores , Glutatión/metabolismo , Imagen Molecular , Colorantes Fluorescentes/química , Colorantes Fluorescentes/metabolismo , Células HeLa , Humanos , Espacio Intracelular/metabolismo , Microscopía Confocal , Estructura Molecular , Oxidación-Reducción
9.
Proc Natl Acad Sci U S A ; 113(18): 4970-5, 2016 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-27084884

RESUMEN

Protein-protein interactions (PPIs) play a central role in most biological processes, and therefore represent an important class of targets for therapeutic development. However, disrupting PPIs using small-molecule inhibitors (SMIs) is challenging and often deemed as "undruggable." We developed a cell-based functional assay for high-throughput screening to identify SMIs for steroid receptor coactivator-3 (SRC-3 or AIB1), a large and mostly unstructured nuclear protein. Without any SRC-3 structural information, we identified SI-2 as a highly promising SMI for SRC-3. SI-2 meets all of the criteria of Lipinski's rule [Lipinski et al. (2001) Adv Drug Deliv Rev 46(1-3):3-26] for a drug-like molecule and has a half-life of 1 h in a pharmacokinetics study and a reasonable oral availability in mice. As a SRC-3 SMI, SI-2 can selectively reduce the transcriptional activities and the protein concentrations of SRC-3 in cells through direct physical interactions with SRC-3, and selectively induce breast cancer cell death with IC50 values in the low nanomolar range (3-20 nM), but not affect normal cell viability. Furthermore, SI-2 can significantly inhibit primary tumor growth and reduce SRC-3 protein levels in a breast cancer mouse model. In a toxicology study, SI-2 caused minimal acute cardiotoxicity based on a hERG channel blocking assay and an unappreciable chronic toxicity to major organs based on histological analyses. We believe that this work could significantly improve breast cancer treatment through the development of "first-in-class" drugs that target oncogenic coactivators.


Asunto(s)
Bencimidazoles/farmacología , Hidrazonas/farmacología , Coactivador 3 de Receptor Nuclear/antagonistas & inhibidores , Animales , Bencimidazoles/farmacocinética , Neoplasias de la Mama/patología , Línea Celular Tumoral , Femenino , Humanos , Hidrazonas/farmacocinética , Ratones , Coactivador 3 de Receptor Nuclear/metabolismo , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Transcripción Genética/efectos de los fármacos
10.
Biochem Pharmacol ; 109: 70-82, 2016 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-27021842

RESUMEN

Agomelatine (AGM), an analog of melatonin, is a potential agonist at melatonin receptors 1/2 and a selective antagonist at 5-hydroxytryptamine 2C receptors. AGM is widely used for the treatment of major depressive episodes in adults. However, multiple adverse effects associated with AGM have been reported in clinical practice. It is little known about AGM metabolism in vitro and in vivo, although metabolism plays a pivotal role in its efficacy and safety. To elucidate metabolic pathways of AGM, we systemically investigated AGM metabolism and its bioactivation in human liver microsomes (HLM) and mice using metabolomic approaches. We identified thirty-eight AGM metabolites and adducts, among which thirty-two are novel. In HLM, we uncovered five GSH-trapped adducts and two semicarbazide-trapped aldehydes. Moreover, we characterized three N-acetyl cysteine conjugated-AGM adducts in mouse urine and feces, which were formed from the degradation of AGM_GSH adducts. Using recombinant CYP450 isoenzymes and chemical inhibitors, we demonstrated that CYP1A2 and CYP3A4 are primary enzymes contributing to the formation of AGM_GSH adducts and AGM_hydrazones. This study provided a global view of AGM metabolism and identified the novel pathways of AGM bioactivation, which could be utilized for further understanding the mechanism of adverse effects related to AGM and possible drug-drug interactions.


Asunto(s)
Acetamidas/orina , Sistema Enzimático del Citocromo P-450/metabolismo , Hipnóticos y Sedantes/orina , Microsomas Hepáticos/metabolismo , Receptores de Melatonina/agonistas , Acetamidas/química , Acetamidas/farmacocinética , Animales , Biotransformación , Heces/química , Regulación de la Expresión Génica , Glutatión/química , Humanos , Hipnóticos y Sedantes/química , Hipnóticos y Sedantes/farmacocinética , Isoenzimas/metabolismo , Redes y Vías Metabólicas/genética , Metabolómica , Ratones , Ratones Endogámicos ICR , Microsomas Hepáticos/efectos de los fármacos , Receptores de Melatonina/genética , Receptores de Melatonina/metabolismo , Semicarbacidas/química , Transducción de Señal
11.
PLoS One ; 10(10): e0140011, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26431029

RESUMEN

Triple negative breast cancer (TNBC) has the poorest prognosis of all types of breast cancer and currently lacks efficient targeted therapy. Chemotherapy is the traditional standard-of-care for TNBC, but is frequently accompanied by severe side effects. Despite the fact that high expression of steroid receptor coactivator 3 (SRC-3) is correlated with poor survival in estrogen receptor positive breast cancer patients, its role in TNBC has not been extensively investigated. Here, we show that high expression of SRC-3 correlates with both poor overall survival and post progression survival in TNBC patients, suggesting that SRC-3 can serve as a prognostic marker for TNBC. Furthermore, we demonstrated that bufalin, a SRC-3 small molecule inhibitor, when introduced even at nM concentrations, can significantly reduce TNBC cell viability and motility. However, because bufalin has minimal water solubility, its in vivo application is limited. Therefore, we developed a water soluble prodrug, 3-phospho-bufalin, to facilitate its in vivo administration. In addition, we demonstrated that 3-phospho-bufalin can effectively inhibit tumor growth in an orthotopic TNBC mouse model, suggesting its potential application as a targeted therapy for TNBC treatment.


Asunto(s)
Bufanólidos/farmacología , Coactivador 3 de Receptor Nuclear/metabolismo , Profármacos/farmacología , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/metabolismo , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Femenino , Humanos , Ratones , Ratones Endogámicos ICR , Ratones SCID , Receptores de Estrógenos/metabolismo
12.
Nat Cell Biol ; 17(9): 1112-23, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26237647

RESUMEN

A fundamental question regarding autophagosome formation is how the shape of the double-membrane autophagosomal vesicle is generated. Here we show that in mammalian cells assembly of an actin scaffold inside the isolation membrane (the autophagosomal precursor) is essential for autophagosomal membrane shaping. Actin filaments are depolymerized shortly after starvation and actin is assembled into a network within the isolation membrane. When formation of actin puncta is disrupted by an actin polymerization inhibitor or by knocking down the actin-capping protein CapZß, isolation membranes and omegasomes collapse into mixed-membrane bundles. Formation of actin puncta is PtdIns(3)P dependent, and inhibition of PtdIns(3)P formation by treating cells with the PI(3)K inhibitor 3-MA, or by knocking down Beclin-1, abolishes the formation of actin puncta. Binding of CapZ to PtdIns(3)P, which is enriched in omegasomes, stimulates actin polymerization. Our findings illuminate the mechanism underlying autophagosomal membrane shaping and provide key insights into how autophagosomes are formed.


Asunto(s)
Citoesqueleto de Actina/metabolismo , Autofagia , Proteína CapZ/fisiología , Membranas Intracelulares/metabolismo , Fagosomas/metabolismo , Citoesqueleto de Actina/ultraestructura , Animales , Células Cultivadas , Membranas Intracelulares/ultraestructura , Fagosomas/ultraestructura , Fosfatos de Fosfatidilinositol/metabolismo , Unión Proteica , Multimerización de Proteína , Transporte de Proteínas , Ratas
13.
ACS Chem Biol ; 10(3): 864-74, 2015 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-25531746

RESUMEN

Glutathione (GSH) plays an important role in maintaining redox homeostasis inside cells. Currently, there are no methods available to quantitatively assess the GSH concentration in live cells. Live cell fluorescence imaging revolutionized the field of cell biology and has become an indispensable tool in current biological studies. In order to minimize the disturbance to the biological system in live cell imaging, the probe concentration needs to be significantly lower than the analyte concentration. Because of this, any irreversible reaction-based GSH probe can only provide qualitative results within a short reaction time and will exhibit maximum response regardless of the GSH concentration if the reaction is completed. A reversible reaction-based probe with an appropriate equilibrium constant allows measurement of an analyte at much higher concentrations and, thus, is a prerequisite for GSH quantification inside cells. In this contribution, we report the first fluorescent probe-ThiolQuant Green (TQ Green)-for quantitative imaging of GSH in live cells. Due to the reversible nature of the reaction between the probe and GSH, we are able to quantify mM concentrations of GSH with TQ Green concentrations as low as 20 nM. Furthermore, the GSH concentrations measured using TQ Green in 3T3-L1, HeLa, HepG2, PANC-1, and PANC-28 cells are reproducible and well correlated with the values obtained from cell lysates. TQ Green imaging can also resolve the changes in GSH concentration in PANC-1 cells upon diethylmaleate (DEM) treatment. In addition, TQ Green can be conveniently applied in fluorescence activated cell sorting (FACS) to measure GSH level changes. Through this study, we not only demonstrate the importance of reaction reversibility in designing quantitative reaction-based fluorescent probes but also provide a practical tool to facilitate redox biology studies.


Asunto(s)
Células Epiteliales/metabolismo , Colorantes Fluorescentes/química , Glutatión/análisis , Imagen Molecular/métodos , Células 3T3-L1 , Animales , Células Epiteliales/ultraestructura , Colorantes Fluorescentes/síntesis química , Glutatión/metabolismo , Células HeLa , Células Hep G2 , Humanos , Ratones , Oxidación-Reducción
14.
Proc Natl Acad Sci U S A ; 110(52): 21165-70, 2013 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-24324172

RESUMEN

Phosphatidylinositol 3,5-bisphosphate [PI(3,5)P2] is a low-abundance phosphoinositide presumed to be localized to endosomes and lysosomes, where it recruits cytoplasmic peripheral proteins and regulates endolysosome-localized membrane channel activity. Cells lacking PI(3,5)P2 exhibit lysosomal trafficking defects, and human mutations in the PI(3,5)P2-metabolizing enzymes cause lysosome-related diseases. The spatial and temporal dynamics of PI(3,5)P2, however, remain unclear due to the lack of a reliable detection method. Of the seven known phosphoinositides, only PI(3,5)P2 binds, in the low nanomolar range, to a cytoplasmic phosphoinositide-interacting domain (ML1N) to activate late endosome and lysosome (LEL)-localized transient receptor potential Mucolipin 1 (TRPML1) channels. Here, we report the generation and characterization of a PI(3,5)P2-specific probe, generated by the fusion of fluorescence tags to the tandem repeats of ML1N. The probe was mainly localized to the membranes of Lamp1-positive compartments, and the localization pattern was dynamically altered by either mutations in the probe, or by genetically or pharmacologically manipulating the cellular levels of PI(3,5)P2. Through the use of time-lapse live-cell imaging, we found that the localization of the PI(3,5)P2 probe was regulated by serum withdrawal/addition, undergoing rapid changes immediately before membrane fusion of two LELs. Our development of a PI(3,5)P2-specific probe may facilitate studies of both intracellular signal transduction and membrane trafficking in the endosomes and lysosomes.


Asunto(s)
Colorantes Fluorescentes/metabolismo , Imagen Molecular/métodos , Fosfatos de Fosfatidilinositol/metabolismo , Canales de Potencial de Receptor Transitorio/metabolismo , Procesamiento de Imagen Asistido por Computador , Microscopía Confocal , Unión Proteica , Canales de Potencial de Receptor Transitorio/genética , Vesículas Transportadoras/metabolismo
15.
J Am Chem Soc ; 135(30): 10938-41, 2013 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-23848502

RESUMEN

Disulfide has been the only widely used functionality to serve as a reduction responsive trigger in drug delivery. We introduce thioester as a novel thiol responsive chemistry for drug delivery, whose reactivity can be conveniently modulated by choosing the appropriate steric environment around the thioester. Compared with disulfides, thioesters are facile to synthesize and have an order of magnitude broader kinetic tunability. A novel traceless reversible protein PEGylation reagent is developed based on thioester chemistry.


Asunto(s)
Polietilenglicoles/química , Compuestos de Sulfhidrilo/química , Ligando Inductor de Apoptosis Relacionado con TNF/química , Esterificación/efectos de los fármacos , Glutatión/farmacología , Humanos , Células Jurkat , Modelos Moleculares , Oxidación-Reducción/efectos de los fármacos , Conformación Proteica , Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo
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