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1.
J Clin Invest ; 133(14)2023 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-37463446

RESUMEN

Human epidermal growth factor receptor 2-targeted (HER2-targeted) therapy is the mainstay of treatment for HER2+ breast cancer. However, the proteolytic cleavage of HER2, or HER2 shedding, induces the release of the target epitope at the ectodomain (ECD) and the generation of a constitutively active intracellular fragment (p95HER2), impeding the effectiveness of anti-HER2 therapy. Therefore, identifying key regulators in HER2 shedding might provide promising targetable vulnerabilities against resistance. In the current study, we found that upregulation of dolichyl-phosphate N-acetylglucosaminyltransferase (DPAGT1) sustained high-level HER2 shedding to confer trastuzumab resistance, which was associated with poor clinical outcomes. Upon trastuzumab treatment, the membrane-bound DPAGT1 protein was endocytosed via the caveolae pathway and retrogradely transported to the ER, where DPAGT1 induced N-glycosylation of the sheddase - ADAM metallopeptidase domain 10 (ADAM10) - to ensure its expression, maturation, and activation. N-glycosylation of ADAM10 at N267 protected itself from ER-associated protein degradation and was essential for DPAGT1-mediated HER2 shedding and trastuzumab resistance. Importantly, inhibition of DPAGT1 with tunicamycin acted synergistically with trastuzumab treatment to block HER2 signaling and reverse resistance. These findings reveal a prominent mechanism for HER2 shedding and suggest that targeting DPAGT1 might be a promising strategy against trastuzumab-resistant breast cancer.


Asunto(s)
Antineoplásicos , Neoplasias de la Mama , Humanos , Femenino , Trastuzumab/farmacología , Trastuzumab/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Transducción de Señal , Proteínas de la Membrana/metabolismo , Resistencia a Antineoplásicos , Línea Celular Tumoral , Antineoplásicos/farmacología
2.
J Pathol ; 260(1): 17-31, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36715683

RESUMEN

Macropinocytosis is an effective strategy to mitigate nutrient starvation. It can fuel cancer cell growth in nutrient-limited conditions. However, whether and how macropinocytosis contributes to the rapid proliferation of hepatocellular carcinoma cells, which frequently experience an inadequate nutrient supply, remains unclear. Here, we demonstrated that nutrient starvation strongly induced macropinocytosis in some hepatocellular carcinoma cells. It allowed the cells to acquire extracellular nutrients and supported their energy supply to maintain rapid proliferation. Furthermore, we found that the phospholipid flippase ATP9A was critical for regulating macropinocytosis in hepatocellular carcinoma cells and that high ATP9A levels predicted a poor outcome for patients with hepatocellular carcinoma. ATP9A interacted with ATP6V1A and facilitated its transport to the plasma membrane, which promoted plasma membrane cholesterol accumulation and drove RAC1-dependent macropinocytosis. Macropinocytosis inhibitors significantly suppressed the energy supply and proliferation of hepatocellular carcinoma cells characterised by high ATP9A expression under nutrient-limited conditions. These results have revealed a novel mechanism that overcomes nutrient starvation in hepatocellular carcinoma cells and have identified the key regulator of macropinocytosis in hepatocellular carcinoma. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/metabolismo , Membrana Celular , Neoplasias Hepáticas/metabolismo , Nutrientes , Fosfolípidos/metabolismo
3.
Theranostics ; 13(1): 339-354, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36593950

RESUMEN

Rationale: Chemoresistance is a major challenge in the clinical management of patients with breast cancer. Mutant p53 proteins tend to form aggregates that promote tumorigenesis in cancers. We here aimed to explore the mechanism for the generation of mutant p53 aggregates in breast cancer and assess its role in inducing chemoresistance. Methods: Expression of BCL2-associated athanogene 2 (BAG2) was evaluated by qRT-PCR, western blotting, and immunohistochemistry in breast cancer patient specimens. The significance of BAG2 expression in prognosis was assessed by Kaplan-Meier survival analysis and the Cox regression model. The roles of BAG2 in facilitating the formation of mutant p53 aggregates were analyzed by co-immunoprecipitation, immunofluorescence, and semi-denaturing detergent-agarose gel electrophoresis assays. The effects of BAG2 on the chemoresistance of breast cancer were demonstrated by cell function assays and mice tumor models. Results: In the present study, we found that BAG2 was significantly upregulated in relapse breast cancer patient tissues and high BAG2 was associated with a worse prognosis. BAG2 localized in mutant p53 aggregates and interacted with misfolded p53 mutants. BAG2 exacerbated the formation of the aggregates and recruited HSP90 to promote the propagation and maintenance of the aggregates. Consequently, BAG2-mediated mutant p53 aggregation inhibited the mitochondrial apoptosis pathway, leading to chemoresistance in breast cancer. Importantly, silencing of BAG2 or pharmacological targeting of HSP90 substantially reduced the aggregates and increased the sensitivity of chemotherapy in breast cancer. Conclusion: These findings reveal a significant role of BAG2 in the chemoresistance of breast cancer via exacerbating mutant p53 aggregates and suggest that BAG2 may serve as a potential therapeutic target for breast cancer patients with drug resistance.


Asunto(s)
Neoplasias de la Mama , Resistencia a Antineoplásicos , Chaperonas Moleculares , Proteína p53 Supresora de Tumor , Animales , Ratones , Línea Celular Tumoral , Resistencia a Antineoplásicos/genética , Proteínas HSP90 de Choque Térmico/metabolismo , Recurrencia Local de Neoplasia , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Neoplasias de la Mama/genética , Humanos , Femenino
4.
Cancer Res ; 82(22): 4191-4205, 2022 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-36112698

RESUMEN

Tumor metastasis is one of the major causes of high mortality in patients with hepatocellular carcinoma (HCC). Sustained activation of STAT3 signaling plays a critical role in HCC metastasis. RNA binding protein (RBP)-mediated posttranscriptional regulation is involved in the precise control of signal transduction, including STAT3 signaling. In this study, we investigated whether RBPs are important regulators of HCC metastasis. The RBP MEX3C was found to be significantly upregulated in highly metastatic HCC and correlated with poor prognosis in HCC. Mechanistically, MEX3C increased JAK2/STAT3 pathway activity by downregulating SOCS3, a major negative regulator of JAK2/STAT3 signaling. MEX3C interacted with the 3'UTR of SOCS3 and recruited CNOT7 to ubiquitinate and accelerate decay of SOCS3 mRNA. Treatment with MEX3C-specific antisense oligonucleotide significantly inhibited JAK2/STAT3 pathway activation, suppressing HCC migration in vitro and metastasis in vivo. These findings highlight a novel mRNA decay-mediated mechanism for the disruption of SOCS3-driven negative regulation of JAK2/STAT3 signaling, suggesting MEX3C may be a potential prognostic biomarker and promising therapeutic target in HCC. SIGNIFICANCE: This study reveals that RNA-binding protein MEX3C induces SOCS3 mRNA decay to promote JAK2/STAT3 activation and tumor metastasis in hepatocellular carcinoma, identifying MEX3C targeting as a potential approach for treating metastatic disease.


Asunto(s)
Carcinoma Hepatocelular , Janus Quinasa 2 , Neoplasias Hepáticas , Estabilidad del ARN , Proteínas de Unión al ARN , Factor de Transcripción STAT3 , Proteína 3 Supresora de la Señalización de Citocinas , Humanos , Carcinoma Hepatocelular/patología , Janus Quinasa 2/genética , Janus Quinasa 2/metabolismo , Neoplasias Hepáticas/patología , ARN Mensajero/genética , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Transducción de Señal , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/metabolismo , Proteína 3 Supresora de la Señalización de Citocinas/genética , Proteína 3 Supresora de la Señalización de Citocinas/metabolismo , Proteínas Supresoras de la Señalización de Citocinas/genética
5.
Discov Oncol ; 13(1): 81, 2022 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-36002694

RESUMEN

BACKGROUND: Distant metastasis is the prominent factor for cancer-induced death of gastric cancer in which peritoneum is one of the dominating targets of gastric cancer metastasis. However, there is still a lack of effective predictive indicators and treatment methods for gastric cancer patients with peritoneal metastasis. METHODS: A clustering assay was used to investigate the cell aggregates formation ability. While the soft agar assay and anoikis assay were performed to detect the anchorage-independent growth and anoikis-resistant ability respectively. Luciferase activity assay, western blotting and immunofluorescence were used to explore the effect of HMMR on AKT signaling activity. The peritoneal implantation model was examined to explore the role of HMMR in vivo. RESULTS: Silencing of HMMR expression markedly reduced the peritoneal metastasis of gastric cancer cells through reducing cell-cell interactions. Mechanistically, HA-HMMR could activate Akt signaling, thus succeeding in distant colonization and metastatic outgrowth. Importantly, inducible depletion of HMMR significantly abrogates peritoneal implantation of gastric cancer in vitro and in vivo. CONCLUSION: Our study highlights that HMMR promotes peritoneal implantation of gastric cancer. A better understanding of HMMR's functions and mechanism might provide a novel therapeutic target and prognostic marker for metastatic gastric cancer.

7.
Clin Transl Med ; 12(1): e725, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-35090098

RESUMEN

Triple-negative breast cancer (TNBC) is fast-growing and highly metastatic with the poorest prognosis among the breast cancer subtypes. Inactivation of glycogen synthase kinase 3 beta (GSK3ß) plays a vital role in the aggressiveness of TNBC; however, the underlying mechanism for sustained GSK3ß inhibition remains largely unknown. Here, we find that protein phosphatase 1 regulatory inhibitor subunit 14C (PPP1R14C) is upregulated in TNBC and relevant to poor prognosis in patients. Overexpression of PPP1R14C facilitates cell proliferation and the aggressive phenotype of TNBC cells, whereas the depletion of PPP1R14C elicits opposite effects. Moreover, PPP1R14C is phosphorylated and activated by protein kinase C iota (PRKCI) at Thr73. p-PPP1R14C then represses Ser/Thr protein phosphatase type 1 (PP1) to retain GSK3ß phosphorylation at high levels. Furthermore, p-PPP1R14C recruits E3 ligase, TRIM25, toward the ubiquitylation and degradation of non-phosphorylated GSK3ß. Importantly, the blockade of PPP1R14C phosphorylation inhibits xenograft tumorigenesis and lung metastasis of TNBC cells. These findings provide a novel mechanism for sustained GSK3ß inactivation in TNBC and suggest that PPP1R14C might be a potential therapeutic target.


Asunto(s)
Glucógeno Sintasa Quinasa 3 beta/efectos de los fármacos , Péptidos y Proteínas de Señalización Intracelular/genética , Neoplasias de la Mama Triple Negativas/genética , Progresión de la Enfermedad , Femenino , Glucógeno Sintasa Quinasa 3 beta/genética , Humanos , Péptidos y Proteínas de Señalización Intracelular/efectos adversos , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/metabolismo
8.
J Phys Chem Lett ; 12(50): 12135-12141, 2021 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-34913699

RESUMEN

This paper describes a photocatalytic hydrogen evolution system that is dynamically and reversibly responsive to the pH of the surrounding solution through the actuation of a microhydrogel (microgel) matrix that hosts the photocatalysts (CdSe/CdS nanorods). The reversible actuation occurs within 0.58 (swelling) and 1.7 s (contraction). ΔpH = 0.01 relative to the pKa of the tertiary amine on the microgel polymer (7.27) results in a reversible change in the average diameter of the microgel hosts by a factor of 2.4 and a change in the photocatalytic turnover frequency (TOF) by a factor of 5. Kinetic isotope effect and photoluminescence quenching experiments reveal that the scavenging of the photoexcited hole by sulfite ions is the rate-limiting step and leads to the observed response of the TOF to pH through the actuation of the microgel. Molecular dynamics simulations quantify a greater local concentration of sulfite hole scavengers for pH < pKa.


Asunto(s)
Hidrogeles/química , Luz , Compuestos de Cadmio/química , Catálisis , Óxido de Deuterio/química , Concentración de Iones de Hidrógeno , Cinética , Simulación de Dinámica Molecular , Nanotubos/química , Compuestos de Selenio/química , Sulfuros/química
9.
Nat Commun ; 12(1): 7006, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34853315

RESUMEN

Nicotine addiction and the occurrence of lymph node spread are two major significant factors associated with esophageal cancer's poor prognosis; however, nicotine's role in inducing lymphatic metastasis of esophageal cancer remains unclear. Here we show that OTU domain-containing protein 3 (OTUD3) is downregulated by nicotine and correlates with poor prognosis in heavy-smoking esophageal cancer patients. OTUD3 directly interacts with ZFP36 ring finger protein (ZFP36) and stabilizes it by inhibiting FBXW7-mediated K48-linked polyubiquitination. ZFP36 binds with the VEGF-C 3-'UTR and recruits the RNA degrading complex to induce its rapid mRNA decay. Downregulation of OTUD3 and ZFP36 is essential for nicotine-induced VEGF-C production and lymphatic metastasis in esophageal cancer. This study establishes that the OTUD3/ZFP36/VEGF-C axis plays a vital role in nicotine addiction-induced lymphatic metastasis, suggesting that OTUD3 may serve as a prognostic marker, and induction of the VEGF-C mRNA decay might be a potential therapeutic strategy against human esophageal cancer.


Asunto(s)
Regulación hacia Abajo/efectos de los fármacos , Neoplasias Esofágicas/metabolismo , Metástasis Linfática , Nicotina/farmacología , Estabilidad del ARN/fisiología , Proteasas Ubiquitina-Específicas/metabolismo , Factor C de Crecimiento Endotelial Vascular/metabolismo , Inductores de la Angiogénesis/farmacología , Animales , Línea Celular Tumoral , Neoplasias Esofágicas/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células HEK293 , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , ARN Mensajero/metabolismo , Tristetraprolina/metabolismo , Proteasas Ubiquitina-Específicas/genética , Factor C de Crecimiento Endotelial Vascular/genética
10.
J Phys Chem A ; 125(39): 8626-8634, 2021 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-34585571

RESUMEN

This paper presents the reaction mechanism, cross sections, and product energy partitioning for the O + CO2 reaction, calculated using Born-Oppenheimer molecular dynamics simulations with the quasiclassical trajectory (BOMD-QCT) method. At collision energies up to 9.5 eV, three reactions, oxygen exchange (above ∼1.5 eV), abstraction (above ∼5.5 eV), and dissociation (above ∼7.5 eV) occur, with abstraction and dissociation involving either an insertion-elimination mechanism or a stripping mechanism. The insertion-elimination mechanism involves the formation of a planar CO3 intermediate which lies 0.52 eV above the ground-state CO2; the energetic barrier for oxygen abstraction via this mechanism is 3.52 eV. Interestingly, the insertion-elimination mechanism predominately contributes to the cross sections at collision energies just above the effective energetic threshold for the abstraction and dissociation reactions; at higher collision energies, the contribution from the stripping mechanism increases and eventually dominates. At a collision energy of 9.5 eV, the cross sections for oxygen exchange, abstraction, and dissociation are 4.17 a02, 1.58 a02, and 0.68 a02, respectively. The lower reaction cross sections, higher effective reaction barrier, and product energy distribution of the stripping mechanism were attributed to the short lifetime (28 fs) of the OCOO species compared with that of the CO3 species (45 fs) that arises in the insertion-elimination mechanism. For the exchange reaction, it is found that roughly 40% of the reactant translational energy ends up in CO2 vibration, which provides a single-collision mechanism to produce highly excited CO2. We also studied intersystem crossing effects using trajectory surface hopping calculations and find no changes compared to single surface (triplet) calculations at energies below 7.5 eV; however, at 7.5 eV and higher the abstraction cross sections are changed by as much as 20%, and the (very small) dissociation cross sections are changed by factors of four or more.

11.
Chem Catal ; 1(1): 106-116, 2021 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-34337591

RESUMEN

The use of visible-light photosensitizers to power [2+2] photocycloadditions that produce complex tetrasubstituted cyclobutanes is a true success of photochemistry, but the scope of this reaction has been limited to activated α, ß-unsaturated carbonyls. This paper describes selective intermolecular homo- and hetero-[2+2] photocycloadditions of terminal and internal aryl conjugated dienes - substrates historically unsuited for this reaction because of their multiple possible reaction pathways and product configurations - through triplet-triplet energy transfer from CdSe nanocrystal photocatalysts, to generate valuable and elusive syn-trans aryl vinylcyclobutanes. The negligible singlet-triplet splitting of nanocrystals' excited states allows them to drive the [2+2] pathway over the competing [4+2] photoredox pathway, a chemoselectivity not achievable with any known molecular photosensitizer. Reversible tethering of the cyclobutane product to the nanocrystal surface results in near quantitative yield of the syn-trans product. Flat colloidal CdSe nanoplatelets produce cyclobutanes coupled at the terminal alkenes of component dienes with up to 89% regioselectivity.

12.
Cancer Res ; 81(13): 3525-3538, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-33975879

RESUMEN

Balancing mRNA nuclear export kinetics with its nuclear decay is critical for mRNA homeostasis control. How this equilibrium is aberrantly disrupted in esophageal cancer to acquire cancer stem cell properties remains unclear. Here we find that the RNA-binding protein interleukin enhancer binding factor 2 (ILF2) is robustly upregulated by nicotine, a major chemical component of tobacco smoke, via activation of JAK2/STAT3 signaling and significantly correlates with poor prognosis in heavy-smoking patients with esophageal cancer. ILF2 bound the THO complex protein THOC4 as a regulatory cofactor to induce selective interactions with pluripotency transcription factor mRNAs to promote their assembly into export-competent messenger ribonucleoprotein complexes. ILF2 facilitated nuclear mRNA export and inhibited hMTR4-mediated exosomal degradation to promote stabilization and expression of SOX2, NANOG, and SALL4, resulting in enhanced stemness and tumor-initiating capacity of esophageal cancer cells. Importantly, inducible depletion of ILF2 significantly increased the therapeutic efficiency of cisplatin and abrogated nicotine-induced chemoresistance in vitro and in vivo. These findings reveal a novel role of ILF2 in nuclear mRNA export and maintenance of cancer stem cells and open new avenues to overcome smoking-mediated chemoresistance in esophageal cancer. SIGNIFICANCE: This study defines a previously uncharacterized role of nicotine-regulated ILF2 in facilitating nuclear mRNA export to promote cancer stemness, suggesting a potential therapeutic strategy against nicotine-induced chemoresistance in esophageal cancer.


Asunto(s)
Resistencia a Antineoplásicos , Neoplasias Esofágicas/patología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células Madre Neoplásicas/patología , Nicotina/farmacología , Proteína del Factor Nuclear 45/metabolismo , ARN Mensajero/metabolismo , Transporte Activo de Núcleo Celular , Animales , Apoptosis , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Proliferación Celular , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Proteína Homeótica Nanog/genética , Proteína Homeótica Nanog/metabolismo , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/metabolismo , Agonistas Nicotínicos/farmacología , Proteína del Factor Nuclear 45/genética , Pronóstico , ARN Mensajero/genética , Factores de Transcripción SOXB1/genética , Factores de Transcripción SOXB1/metabolismo , Tasa de Supervivencia , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
13.
J Hematol Oncol ; 14(1): 6, 2021 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-33407765

RESUMEN

BACKGROUND: HOMER family scaffolding proteins (HOMER1-3) play critical roles in the development and progression of human disease by regulating the assembly of signal transduction complexes in response to extrinsic stimuli. However, the role of HOMER protein in breast cancer remains unclear. METHODS: HOMER3 expression was examined by immunohistochemistry in breast cancer patient specimens, and its significance in prognosis was assessed by Kaplan-Meier survival analysis. The effects of HOMER3 in growth factor-induced ß-Catenin activation were analyzed by assays such as TOP/FOP flash reporter, tyrosine phosphorylation assay and reciprocal immunoprecipitation (IP) assay. Role of HOMER3 in breast cancer metastasis was determined by cell function assays and mice tumor models. RESULTS: Herein, we find that, among the three HOMER proteins, HOMER3 is selectively overexpressed in the most aggressive triple negative breast cancer (TNBC) subtype, and significantly correlates with earlier tumor metastasis and shorter patient survival. Mechanismly, HOMER3 interacts with both c-Src and ß-Catenin, thus providing a scaffolding platform to facilitate c-Src-induced ß-Catenin tyrosine phosphorylation under growth factor stimulation. HOMER3 promotes ß-Catenin nuclear translocation and activation, and this axis is clinically relevant. HOMER3 promotes and is essential for EGF-induced aggressiveness and metastasis of TNBC cells both in vitro and in vivo. CONCLUSION: These findings identify a novel role of HOMER3 in the transduction of growth factor-mediated ß-Catenin activation and suggest that HOMER3 might be a targetable vulnerability of TNBC.


Asunto(s)
Proteínas de Andamiaje Homer/metabolismo , Neoplasias Pulmonares/secundario , Neoplasias de la Mama Triple Negativas/patología , beta Catenina/metabolismo , Animales , Línea Celular Tumoral , Femenino , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Ratones Endogámicos BALB C , Ratones Desnudos , Fosforilación , Neoplasias de la Mama Triple Negativas/metabolismo , Tirosina/metabolismo
14.
Cancer Lett ; 503: 43-53, 2021 04 10.
Artículo en Inglés | MEDLINE | ID: mdl-33352248

RESUMEN

Chemotherapy regimens containing cisplatin remain the first-line treatments for patients with oral squamous cell cancer (OSCC); however, the treatment effect is often transient because of chemoresistance and recurrence. Understanding the mechanisms of chemoresistance in OSCC might provide novel targetable vulnerabilities. In the present study, we revealed that Forkhead box D1 (FOXD1) is upregulated in OSCC and predicted poor prognosis. Moreover, ectopic expression of FOXD1 promoted, while silencing of FOXD1 inhibited, the epithelial-mesenchymal transition (EMT) and chemoresistance of OSCC, both in vitro and in vivo. Mechanistically, FOXD1 binds to the promoter of long non-coding RNA Cytoskeleton Regulator RNA (CYTOR) and activates its transcription. CYTOR then acts as a competing endogenous RNA to inhibit miR-1252-5p and miR-3148, thus upregulating lipoma preferred partner (LPP) expression. Importantly, the CYTOR/LPP axis was proven to be essential for FOXD1-induced EMT and chemoresistance in OSCC. These findings reveal a novel mechanism for the chemotherapy resistance of OSCC, suggesting that FOXD1 might be a potential prognostic marker and anti-resistance therapeutic target.


Asunto(s)
Carcinoma de Células Escamosas/patología , Resistencia a Antineoplásicos , Factores de Transcripción Forkhead/metabolismo , Neoplasias de la Boca/patología , ARN Largo no Codificante/genética , Regulación hacia Arriba , Animales , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Línea Celular Tumoral , Proteínas del Citoesqueleto/genética , Transición Epitelial-Mesenquimal , Factores de Transcripción Forkhead/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Proteínas con Dominio LIM/genética , Ratones , MicroARNs/genética , Neoplasias de la Boca/genética , Neoplasias de la Boca/metabolismo , Trasplante de Neoplasias , Pronóstico , Regiones Promotoras Genéticas
15.
Angew Chem Int Ed Engl ; 59(31): 13037-13043, 2020 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-32347593

RESUMEN

We investigate a family of dinuclear dysprosium metallocene single-molecule magnets (SMMs) bridged by methyl and halogen groups [Cp'2 Dy(µ-X)]2 (Cp'=cyclopentadienyltrimethylsilane anion; 1: X=CH3 - ; 2: X=Cl- ; 3: X=Br- ; 4: X=I- ). For the first time, the magnetic easy axes of dysprosium metallocene SMMs are experimentally determined, confirming that the orientation of them are perpendicular to the equatorial plane which is made up of dysprosium and bridging atoms. The orientation of the magnetic easy axis for 1 deviates from the normal direction (by 10.3°) due to the stronger equatorial interactions between DyIII and methyl groups. Moreover, its magnetic axes show a temperature-dependent shifting, which is caused by the competition between exchange interactions and Zeeman interactions. Studies of fluorescence and specific heat as well as ab initio calculations reveal the significant influences of the bridging ligands on their low-lying exchange-based energy levels and, consequently, low-temperature magnetic properties.

16.
Adv Mater ; 32(8): e1906600, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31944429

RESUMEN

A novel method for synthesizing and photopatterning colloidal crystals via light-responsive DNA is developed. These crystals are composed of 10-30 nm gold nanoparticles interconnected with azobenzene-modified DNA strands. The photoisomerization of the azobenzene molecules leads to reversible assembly and disassembly of the base-centered cubic (bcc) and face-centered cubic (fcc) crystalline nanoparticle lattices. In addition, UV light is used as a trigger to selectively remove nanoparticles on centimeter-scale thin films of colloidal crystals, allowing them to be photopatterned into preconceived shapes. The design of the azobenzene-modified linking DNA is critical and involves complementary strands, with azobenzene moieties deliberately staggered between the bases that define the complementary code. This results in a tunable wavelength-dependent melting temperature (Tm ) window (4.5-15 °C) and one suitable for affecting the desired transformations. In addition to the isomeric state of the azobenzene groups, the size of the particles can be used to modulate the Tm window over which these structures are light-responsive.


Asunto(s)
ADN/química , Nanopartículas del Metal/química , Rayos Ultravioleta , Compuestos Azo/química , Oro/química , Dispersión del Ángulo Pequeño , Temperatura de Transición , Difracción de Rayos X
17.
Nano Lett ; 19(10): 7309-7316, 2019 10 09.
Artículo en Inglés | MEDLINE | ID: mdl-31518135

RESUMEN

The plasmonic properties of tip-substrate composite systems are of vital importance to near-field optical spectroscopy, in particular tip-enhanced Raman spectroscopy (TERS), which enables operando studies of nanoscale chemistry at a single molecule level. The nanocavities formed in the tip-substrate junction also offer a highly tunable platform for studying field-matter interactions at the nanoscale. While the coupled nanoparticle dimer model offers a correct qualitative description of gap-mode plasmon effects, it ignores the full spectrum of multipolar tip plasmon modes and their interaction with surface plasmon polariton (SPP) excitation in the substrate. Herein, we perform the first tip-enhanced Raman excitation spectroscopy (TERES) experiment and use the results, both in ambient and aqueous media, in combination with electrodynamics simulations, to explore the plasmonic response of a Au tip-Au substrate composite system. The gap-mode plasmon features a wide spectral window corresponding to a host of tip plasmon modes interacting with the plasmonic substrate. Simulations of the electric field confinement demonstrate that optimal spatial resolution is achieved when a hybrid plasmon mode that combines a multipolar tip plasmon and a substrate SPP is excited. Nevertheless, a wide spectral window over 1000 nm is available for exciting the tip plasmon with high spatial resolution, which enables the simultaneous resonant detection of different molecular species. This window is robust as a function of tip-substrate distance and tip radius of curvature, indicating that many choices of tips will work, but it is restricted to wavelengths longer than ∼600 nm for the Au tip-Au substrate combination. Other combinations, such as Ag tip-Ag substrate, can access wavelengths as low as 350 nm.

18.
Ann Surg Treat Res ; 97(1): 1-6, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31297346

RESUMEN

PURPOSE: The combination of indocyanine green and methylene blue (ICG + MB) was reported to be an efficient tracer method in sentinel lymph node biopsy (SLNB). However, whether this method is superior to MB only or carbon nanoparticles (CN) is controversial. This study was to evaluate the efficacy of the three methods in SLNB for breast cancer, and to analyze its influencing factors. METHODS: One hundred eighty patients with early breast cancer were recruited and randomly divided into 3 groups. Each group comprising of 60 patients with SLNB using ICG + MB, MB, and CN, respectively. Then the 3 groups were compared in detection rate, mean number of SLNs, and the detection rates and number of metastatic sentinel lymph nodes (SLNs). RESULTS: The detection rate of SLNs was 100% (60 of 60) in ICG + MB group, 96.7% (58 of 60), and 98.3% (59 of 60) in MB and CN group, respectively, with no significant difference (P = 0.362). Totally, 204 SLNs (mean ± standard deviation [SD] [range], 3.4 ± 1.4 [2-8]) were detected in ICG + MB group, 102 (1.7 ± 0.7 [0-3]) and 145 (2.4 ± 0.7 [0-6]) in MB and CN group, indicating significant difference (P < 0.001). The detection rate of metastatic SLN was 23.3% (14 of 60) in ICG + MB group, which was higher than 18.3% (11 of 60) and 20% (11 of 60) in MB and CN group, respectively, but showed no statistical significance (P = 0.788). CONCLUSION: ICG + MB method was superior to MB only and CN only methods in the mean number of SLNs, thus predicting axillary lymph node metastasis more accurately. Therefore, in areas where the standard method is not available, ICG + MB may be more suitable as an alternative tracer for SLNB.

19.
Dalton Trans ; 48(28): 10407-10411, 2019 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-31241102

RESUMEN

To conclude the design principle for high-performance erbium-based single-ion magnets (SIMs), two half-sandwich type erbium complexes 1Er [(LOMe)Er(COT)] (LOMe = [(η5-C5H5)Co{P([double bond, length as m-dash]O)(OMe)2}3], COT = cyclooctatetraenyl) and 2Er [(THF)2(OAr)Er(COT)] (Ar = 2,6-Dipp2C6H3, Dipp = 2,6-diisopropylphenyl) were synthesized, and structurally and magnetically characterized. Both of them exhibited SIM behavior. Their magnetic relaxation behaviours were further elucidated by ab initio calculations and near-IR emission spectroscopy. The results demonstrated that an axial ligand with a weaker electron-donating effect was preferential to construct high blocking barrier erbium-based SIMs.

20.
Onco Targets Ther ; 12: 2171-2180, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30988621

RESUMEN

BACKGROUND: IRAK1 has been shown to be abnormally expressed in a set of tumors leading to tumorigenesis and progression. IRAK1 is a therapeutic target that drives breast cancer metastasis and resistance to paclitaxel. However, the exact role of IRAK1 in neoadjuvant chemotherapy (NCT) for breast cancer remains unclear. The aim of this study was to investigate the relationship between the expression of IRAK1 and the clinicopathological parameters and survival prognosis of breast cancer patients treated with NCT. PATIENTS AND METHODS: Based on the clinical data and mRNA microarray data from 1,085 breast cancer patients in The Cancer Genome Atlas, the correlation between IRAK1 expression and clinicopathological parameters of breast cancer was analyzed. Immunohistochemistry was performed to evaluate the expression of IRAK1. The Human Protein Atlas and the String database were used to analyze the expression of IRAK1 protein and its interaction with altered neighboring proteins in breast cancer. IRAK1 alteration was analyzed in cBioPortal database. GEO enrichment of IRAK1 was performed using WEB-based Gene SeT AnaLysis Toolkit. RESULTS: The expression of IRAK1 was significantly downregulated following NCT. The decreased expression of IRAK1 following NCT was positively correlated with reduced tumor size. Finally, survival analysis confirmed that a shorter survival period was correlated to higher expression of IRAK1 both before and after NCT. CONCLUSION: These findings advanced our understanding about the expression pattern of IRAK1 in breast cancer, especially in those patients who were treated with NCT, suggesting that IRAK1 could be used as a prognostic indicator, as well as a potential indicator for evaluating NCT efficacy for breast cancer patients.

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