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BACKGROUND: Depression is a heterogeneous disorder with high morbidity and disability rates that poses serious problems in regard to mental health care. It is now well established that N-methyl D-aspartate receptors (NMDARs) modulators are being increasingly explored as potential therapeutic options for treating depression, although relatively little is known about their mechanisms of action. NMDARs are glutamate-gated ion channels that are ubiquitously expressed in the central nervous system (CNS) and they have been shown to play key roles in excitatory synaptic transmission. GluN2A, the predominant Glu2N subunit of functional NMDARs in neurons, is involved in various physiological processes in the CNS and is associated with diseases such as anxiety, depression, and schizophrenia. However, the role of GluN2A in the pathophysiology of depression has not yet been elucidated. METHODS: We reviewed several past studies in order to better understand the function of GluN2A in depression. Additionally, we also summarized the pathogenesis of depression based on the regulation of GluN2A expression, particularly its interaction with neuroinflammation and neurogenesis, which has received considerable critical attention and is highly implicated in the onset of depression. RESULTS: These evidences suggest that GluN2A overexpression impairs structural and functional synaptic plasticity, which contributes to the development of depression. Consequently, this knowledge is vital for the development of selective antagonists targeting GluN2A subunits using pharmacological and molecular methods. CONCLUSIONS: Specific inhibition of GluN2A NMDAR subunit is resistant to chronic stress-induced depressive-like behaviors, making them promising targets for the development of novel antidepressants.
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Ciprofloxacin (CIP) is a widely used broad-spectrum antibiotic and has been associated with various side effects, making its accurate detection crucial for patient safety, drug quality compliance, and environmental and food safety. This study presents the development of a ternary nucleotide-lanthanide coordination nanoprobe, GMP-Tb-BDC (GMP: guanosine 5'-monophosphate, BDC: 2-amino-1,4-benzenedicarboxylic acid), for the sensitive and ratiometric detection of CIP. The GMP-Tb-BDC nanoprobe was constructed by incorporating the blue-emissive ligand BDC into the Tb/GMP coordination polymers. Upon the addition of CIP, the fluorescence of terbium ion (Tb3+ ) was significantly enhanced due to the coordination and fluorescence sensitization properties of CIP, while the emission of the BDC ligand remained unchanged. The nanoprobe demonstrated good linearity in the concentration range of 0-10 µM CIP. By leveraging mobile phone software to analyze the color signals, rapid on-site analysis of CIP was achieved. Furthermore, the nanoprobe exhibited accurate analysis of CIP in actual drug and milk samples. This study showcases the potential of the GMP-Tb-BDC nanoprobe for practical applications in CIP detection.
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Elementos de la Serie de los Lantanoides , Humanos , Ciprofloxacina , Nucleótidos , Ligandos , Terbio , Guanosina MonofosfatoRESUMEN
Sequential C-H functionalization of molecules containing multiple C-H bonds can efficiently lead to structural diversity. Herein we present the first chelation-assisted sequential α-/ß-C-H functionalization of E-styrenes with simple alkenes and alkynes in excellent regio- and stereo-selectivity. The process involves α C-H functionalization by six-membered exo-cyclopalladation to result in tri- and tetrasubstituted 1,3-dienes and ß C-H functionalization through seven-membered endo-cyclopalladation to produce tetra- and pentasubstituted 1,3,5-trienes in up to 97 % yield with up to >99/1 E/Z selectivity, both enabled by the chelation assistance of pyrazinamide. The protocol is demonstrated to be widely applicable, tolerant to a wide range of functional groups and bioactive fragments, and suitable for gram-scale synthesis as well as one-pot and two step preparation of trienes. Mechanistic experiments and density functional theory (DFT) calculations were performed to elucidate the selectivity and reactivity.
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Long noncoding RNAs play important roles in the occurrence and development of many malignant cancers. This study focuses on the effects of LINC01087 on gastric cancer and its underlying mechanism. In the present study, LINC01087 and CAAP1 were found to be upregulated, and miR-135a-5p was diminished in gastric cancer specimens and cells. Inhibition of LINC01087 resulted in cell proliferation inhibition and induced cell apoptosis through the intrinsic apoptosis signaling pathway, as evidenced by the activation of caspase-3 and caspase-9. An investigation of the signaling pathway revealed that the effects on proliferation and apoptosis following LINC01087 knockdown were mediated by suppression of CAAP1. Furthermore, application of a miR-135a-5p inhibitor or overexpression of CAAP1 could attenuate the apoptotic effect achieved by LINC01087 inhibition, confirming the involvement of miR-135a-5p/CAAP1 signaling in the occurrence of gastric cancer. In conclusion, the LINC01087/miR-135a-5p/CAAP1 axis modulates gastric cancer tumorigenesis and pathogenesis and presents new insight into gastric cancer targeted therapy.
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MicroARNs , Neoplasias Gástricas , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Neoplasias Gástricas/genética , Apoptosis/genética , Carcinogénesis , Transducción de Señal , Proliferación Celular , Línea Celular Tumoral , Regulación Neoplásica de la Expresión GénicaRESUMEN
Both geometric architecture and electronic configurations of heme proteins contribute to its activity. In this work we designed and synthesized a series of four copper(II) porphyrin complexes (4-, 3-, 2- and 1-Cu) where the molecular conformations are modulated by a pair of stepwise shortened straps on the same porphyrin side (cis-ortho) to give double bow-shaped skeletons. Single crystal structures demonstrate that the straps gradually increase the saddle deformation and the deviation of the metal centers, which is in accordance with two, unusual d-orbital reconstructions of two different ground states, as revealed by 4â K EPR and DFT calculations. In the study of the electrocatalytic hydrogen evolution reaction (HER), 1-Cu, with the shortest straps, showed the most apparent improvement of activity. Second coordination sphere (SCS) effects created by the double bow-shaped architecture and the strong saddle porphyrin core in 1-Cu are found to play key roles in proton trapping during the catalytic process. The work contributes a novel strategy to improve the catalytic performance of heme analogs through ligand geometric modulation.
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Hemoproteínas , Porfirinas , Cobre , Hemo , Hidrógeno , Conformación MolecularRESUMEN
Multiple self-construction behavior of cyclic oligoesters is described. Rigid braces and elastic hinges are periodically incorporated into these cyclomers, which enables these rings to form various topological frameworks, such as holes, caves or cages with different sizes and shapes, through self-folding. Among them, the cave-type cyclomer self-assembles into nanotunnels and then forms porous materials via self-packing of these tunnels. This discovery provides a new perspective for the construction of novel materials aided by multiple supramolecular effects. In this work, the simplest rigid brace components and ones with soft hinges were chosen to construct cyclomers to confirm the supramolecular strategy.
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Tirantes , PorosidadRESUMEN
Neuro-degenerative disease is a common progressive nervous system disorder that leads to serious clinical consequences. Gait rhythm dynamics analysis is essential for evaluating clinical states and improving quality of life for neuro-degenerative patients. The magnitude of stride-to-stride fluctuations and corresponding changes over time-gait dynamics-reflects the physiology of gait, in quantifying the pathologic alterations in the locomotor control system of health subjects and patients with neuro-degenerative diseases. Motivated by algebra topology theory, a topological data analysis-inspired nonlinear framework was adopted in the study of the gait dynamics. Meanwhile, the topological representation-persistence landscapes were used as input of classifiers in order to distinguish different neuro-degenerative disease type from healthy. In this work, stride-to-stride time series from healthy control (HC) subjects are compared with the gait dynamics from patients with amyotrophic lateral sclerosis (ALS), Huntington's disease (HD), and Parkinson's disease (PD). The obtained results show that the proposed methodology discriminates healthy subjects from subjects with other neuro-degenerative diseases with relatively high accuracy. In summary, our study is the first attempt to provide a topological representation-based method into the disease classification with gait rhythms measured from the stride intervals to visualize gait dynamics and classify neuro-degenerative diseases. The proposed method could be potentially used in earlier interventions and state monitoring.
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Esclerosis Amiotrófica Lateral/fisiopatología , Marcha/fisiología , Enfermedad de Huntington/fisiopatología , Enfermedad de Parkinson/fisiopatología , Adulto , Anciano , Esclerosis Amiotrófica Lateral/clasificación , Área Bajo la Curva , Teorema de Bayes , Estudios de Casos y Controles , Árboles de Decisión , Femenino , Humanos , Enfermedad de Huntington/clasificación , Masculino , Persona de Mediana Edad , Dinámicas no Lineales , Enfermedad de Parkinson/clasificación , Reconocimiento de Normas Patrones Automatizadas , Curva ROCRESUMEN
A heme oxygen binding behavior was described through a unique geometric and electronic comparison of zinc porphyrin complexes. In this work, a charge transfer model for saddled metalloporphyrin complexes outlined the push effects of the ring nonplanarity and axial imidazole, and the pull effect of the axial dioxygen. The origin and role of the horizontal (ring nonplanarity) push effect and its relationship to the vertical (axial ligand) push/pull effect and its contribution to dioxygen binding were considered from the perspectives of crystal structures, theoretical calculations, and bathochromic shifts. Single-point energy and molecular orbital calculations starting from crystal structures were used to obtain the electronic structures of zinc porphyrin complexes. This study not only revealed that the electronic behavior of metalloporphyrins is driven by ring nonplanarity and axial ligation but also afforded new insight into the oxygen carrier mechanism in heme.
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Hemo/química , Metaloporfirinas/química , Transporte de Electrón , Modelos Moleculares , Conformación MolecularRESUMEN
BACKGROUND: Hepatocellular carcinoma (HCC) is a common human malignant cancer due to a high metastatic capacity and the recurrence rate is also high. This study is aim to investigate the role of musashi1 as a potential biomarker for therapy of HCC. METHODS: The mRNA and protein expression levels of musashi1 were detected in HCC samples and cell lines. The malignant properties of HCC cells, including proliferation, invasion and migration were measured by overexpressing or knocking down expression of musashi1. Additionally, the correlation between musashi1 and clinicopathological indexes and prognosis were analyzed. The expression of CD44 was measured and the correlation between CD44 and musashi1 was analyzed. RESULTS: In vitro cytological experiments demonstrated that musashi1 was elevated in HCC samples and cell lines and this increased expression affected cancer cell viability, migration and invasive capacity by activating of the Wnt/ß-catenin signaling pathway. Analysis of clinicopathological characteristics suggested that up-regulation of musashi1 was related to metastasis potential and a poor prognosis. Besides, there was a positive correlation between CD44 and musashi1 expression. Upregulation of musashi1 in malignant liver tumors may have contributed to the maintenance of stem-cell like characteristics of HCC cells. CONCLUSIONS: Upregulation of musashi1 could enhance malignant development of HCC cells and thus might be a novel marker for HCC therapy.
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Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Proteínas de Unión al ARN/metabolismo , Vía de Señalización Wnt , Actinas/metabolismo , Proteína de la Poliposis Adenomatosa del Colon/metabolismo , Carcinoma Hepatocelular/mortalidad , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/secundario , Proliferación Celular , Transformación Celular Neoplásica , Ciclina D1/metabolismo , Femenino , Humanos , Receptores de Hialuranos/metabolismo , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Terapia Molecular Dirigida , Invasividad Neoplásica , Metástasis de la Neoplasia , Pronóstico , ARN Mensajero/metabolismo , Regulación hacia Arriba , beta Catenina/metabolismoRESUMEN
Triplet-triplet energy transfer (EnT) is a fundamental activation pathway in photocatalysis. In this work, we report the mechanistic origins of the triplet excited state of carbazole-cyanobenzene donor-acceptor (D-A) fluorophores in EnT-based photocatalytic reactions and demonstrate the key factors that control the accessibility of the 3LE (locally excited triplet state) and 3CT (charge-transfer triplet state) via a combined photochemical and transient absorption spectroscopic study. We found that the energy order between 1CT (charge transfer singlet state) and 3LE dictates the accessibility of 3LE/3CT for EnT, which can be effectively engineered by varying solvent polarity and D-A character to depopulate 3LE and facilitate EnT from the chemically more tunable 3CT state for photosensitization. Following the above design principle, a new D-A fluorophore with strong D-A character and weak redox potential is identified, which exhibits high efficiency for Ni(II)-catalyzed cross-coupling of carboxylic acids and aryl halides with a wide substrate scope and high selectivity. Our results not only provide key fundamental insight on the EnT mechanism of D-A fluorophores but also establish its wide utility in EnT-mediated photocatalytic reactions.
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The electrons of NO and Co are strongly delocalized in normal {Co-NO}8 species. In this work, {Co-NO}8 complexes are induced to convert from (CoII)+â¢-NO⢠to CoIII-NO- by a core contraction of 0.06 Å in saddled cobalt(II) porphyrins. This intramolecular electron transfer mechanism indicates that nonplanarity of porphyrin is involved in driving conversion of the NO units from electrophilic NO⢠as a bent geometry to nucleophilic NO- as a linear geometry. This implies that distortion acts as a trigger in enzymes containing tetrapyrrole. The electronic behaviors of the CoII ions and Co-NO moieties were confirmed by X-ray crystallography, EPR spectroscopy, theoretical calculation, UV-vis and IR spectroscopy, and electrochemistry.
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Cobalto/química , Óxido Nítrico/química , Tetrapirroles/química , Transporte de Electrón , Modelos Moleculares , Estructura Molecular , Teoría Cuántica , Tetrapirroles/síntesis químicaRESUMEN
The predominant distortion of heme is responsible for its electronic activity, catalytic ability and spectral properties. In this work, altogether 12 new X-ray structures of saddled, waved and ruffled porphyrins are reported. Three types of deformed porphyrins as mimics of heme were evaluated and analyzed by geometric deconstruction, spectral comparison, and electrochemical tracking, which shows a unique relationship of deformation fashions and distortion degree to the geometry of the core and electron transfer ability of rings in these enzyme containing porphyrins. These mimics can adjust their core geometry for changing the structures of potential metals; while for rings themselves, they can also regulate the electron activity by switching the HOMO of the large π systems. These deformed porphyrins can be used as ideal mimics for heme. These findings help us to understand the principle and contribution of these deformations to electron transfer in catalytic oxidation and photoreactions. The nonplanar mimics have been synthesized through a modular synthetic approach under Adler-Longo or Lindsey condensation conditions.
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The free unpaired electron in Fe(3+) ions cannot be directly removed, and needs a transfer pathway with at least four steps to overcome the high energy barriers to form Fe(4+) ions. Fine changes in the electronic structure of Fe(3+) ions on spin conversion were identified through a deeper analysis of the diffraction, spectral and electrochemical data for six non-planar iron porphyrins. Fe(3+) ions can form four d electron tautomers as the compression of the central ion is increased. This indicates that the Fe(3+) ion undergoes a multistep electron transfer where the total energy gap of electron transfer is split into several smaller gaps to form high-valent Fe(4+) ions. We find that the interchange of these four electron tautomers is clearly related to the core size of the macrocycle in the current series. The large energy barrier to produce iron(iv) complexes is overcome through a gradient effect of multiple energy levels. In addition, a possible porphyrin Fe(3+)Ë radical may be formed from its stable isoelectronic form, porphyrin Fe(3+), under strong core contraction. These results indicate the important role of heme distortion in its catalytic oxidation functions.
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Hemo/química , Hierro/química , Oxígeno/química , Porfirinas/química , Catálisis , Cobalto/química , Cristalografía por Rayos X , Espectroscopía de Resonancia por Spin del Electrón , Electrones , Radicales Libres , Iones , Modelos Moleculares , Conformación Molecular , Estructura Molecular , Oxidación-ReducciónRESUMEN
In this work, four saddled Pd(II) porphyrins were developed as photocatalyst for N-dealkylation of triethyl Rhodamine (TER) under visible light, and their catalytic ability was found to be negatively related to the out-of-plane of their macrocycles. Two important relationships involving the metalloporphyrins as catalyst were revealed: (1) a photoexcitative semiconductor effect between the 4dx2-ᵧ2(Pd) and a2u(π) orbitals of Pd(II) porphyrin on the dealkylation. (2) a domino process from strap length, ring geometry, core deformation, d-π gap variation, to photocatalytic activity. Two revelations imply a unidirectional electron transfer route from axial ligand, to central metal, to porphyrin ring based on photoexcitation and guide the design and development of complex photocatalysts, and their revelation is attributed to the acquisition of a series of Pd(II) porphyrins with continuous ring distortion. The findings help to understand the photocatalytic single electron transfer (SET)-first mechanism based on metallic complex.
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The rotation of meso-aryl groups in porphyrins depends on the degree of macrocyclic distortion and is also influenced by the surrounding temperature. Dynamic NMR methods and crystal structures of series of nonplanar metalloporphyrins reveal that macrocyclic distortion lowers the rotational barrier by weakening the nonbinding interactions of neighboring groups, while increased temperature allows the rotational barrier to be overcome more readily. Two empirical methods are developed to acquire the rotational barrier. This type of strained molecule can act as an adjustable molecular turnstile through adjusting the degree of macrocyclic distortion and changing the surrounding temperature.
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Laparoscopic pancreaticoduodenectomy (LPD) is a technically demanding procedure but is gradually gaining acceptance in clinical practice. This study was performed to compare the short-term outcomes of LPD with open pancreaticoduodenectomy (OPD). The perioperative data of the patients who underwent LPD (nâ =â 25) and OPD (nâ =â 40) from January 1, 2017 to December 31, 2021 at Zhangjiagang Hospital Affiliated to Soochow University were collected and retrospectively analyzed. All patients received R0 resection, and none of the patients died within the perioperative period. The preoperative data (gender, age, body mass index [BMI], and preoperative bilirubin), the intraoperative data (operative time, number of retrieved lymph nodes), and postoperative data (level 1 monitoring time, postoperative fluid diet time, postoperative fluid feeding time, and hospitalization cost) were comparable between the 2 groups (Pâ >â .05). The estimated blood loss, abdominal drainage tube removal time, postoperative hospital stay, catheter removal time, and analgesic drug use were significantly lesser in the LPD group, when compared to the OPD group (Pâ <â .05). LPD is safe and feasible. Compared to OPD, LPD has less surgical trauma, less intraoperative bleeding, and faster postoperative recovery.
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Laparoscopía , Neoplasias Pancreáticas , Humanos , Pancreaticoduodenectomía/efectos adversos , Pancreaticoduodenectomía/métodos , Estudios Retrospectivos , Neoplasias Pancreáticas/cirugía , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/cirugía , Tiempo de Internación , Resultado del Tratamiento , Laparoscopía/métodosRESUMEN
Background: Gallbladder carcinoma (GBC) is a biliary tract tumor with a high mortality rate. The objectives of this study were to explore the risk factors of GBC in patients with gallstones and to establish effective screening indicators. Methods: A total of 588 patients from medical centers in two different regions of China were included in this study and defined as the internal test samples and the external validation samples, respectively. We retrospectively reviewed the differences in clinicopathologic data of the internal test samples to find the independent risk factors that affect the occurrence of GBC. Then, we constructed three different combined predictive factors (CPFs) through the weighting method, integral system, and nomogram, respectively, and named them CPF-A, CPF-B, and CPF-C sequentially. Furthermore, we evaluated these indicators through calibration and DCA curves. The ROC curve was used to analyze their diagnostic efficiency. Finally, their diagnostic capabilities were validated in the external validation samples. Results: In the internal test samples, the results showed that five factors, namely, age (RR = 3.077, 95% CI: 1.731-5.496), size of gallstones (RR = 13.732, 95% CI: 5.937-31.762), course of gallstones (RR = 2.438, 95% CI: 1.350-4.403), CEA (RR = 9.464, 95% CI: 3.394-26.392), and CA199 (RR = 9.605, 95% CI: 4.512-20.446), were independent risk factors for GBC in patients with gallstones. Then, we established three predictive indicators: CPF-A, CPF-B, and CPF-C. These models were further validated using bootstrapping with 1,000 repetitions. Calibration and decision curve analysis showed that the three models fit well. Meanwhile, multivariate analysis showed that CPF-B and CPF-C were independent risk factors for GBC in patients with gallstones. In addition, the validation results of the external validation samples are essentially consistent with the internal test samples. Conclusion: Age (≤58.5 vs. >58.5 years), size of gallstones (≤1.95 vs. >1.95cm), course of gallstones (≤10 vs. >10 years), CEA (≤5 vs. >5 ng/ml), and CA199 (≤37 vs. >37 U/ml) are independent risk factors for GBC in patients with gallstones. When positive indicators were ≥2 among the five independent risk factors or the score of the nomogram was >82.64, the risk of GBC was high in gallstone patients.
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Background and Aims: The study aimed to create a new staging model for radiotherapy-based treatment for prognostic hepatocellular carcinoma (HCC) classification. Methods: The training cohort comprised 658 patients receiving stereotactic body radiotherapy and external validation cohort comprised 533 patients receiving three-dimensional conformal radiotherapy and intensity-modulated radiotherapy. We established a modified staging system as follows: stage I, solitary nodule without macrovascular invasion, or 2-3 nodules no more than 3.0 cm apart, and performance status (PS) 0-2 (Ia: ALBI-1 grade; Ib: ALBI-2 or 3 grade); stage II: 2-3 nodules with any one nodule more than 3.0-cm apart, or ≥4 nodules, and performance status 0-2 (IIa: ALBI-1 grade; IIb: ALBI-2 grade); stage III: macrovascular invasion, regional lymph node metastasis or distant metastasis, and performance status 0-2 (IIIa: ALBI-1 grade; IIIb: ALBI-2 grade); stage IV: performance status 3-4, or performance status 0-2 with ALBI-3 grade. We analyzed long-term overall survival based on different stages. Results: The staging model showed an excellent ability to discriminate patients according to four stages and seven substages with notably different curves in the training and validation cohort. The median survival decreased from stages I to IV with 63.0 months in stage I (not reached in Ia, and 53.0 months in Ib), 24.0 months in stage II (28.0 months in IIa, and 22.0 months in IIb), 11.0 months in stage III (18.0 months in IIIa, and 9.0 months in IIIb), and less than 9.0 months in stage IV in the training cohort. Conclusions: The modified staging model may provide an alternative for clinical radiation oncologists.
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Ruffle- and dome-type porphyrins were developed as model systems to investigate the role of deformation mode and degree of distortion in heme. Their crystal structures revealed that as the degree of distortion increases, cavity size can be contracted in the ruffle mode and expanded in the dome mode, and the size of cavity can exceed the limit of free metal ions from the fourth period (see scheme).
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Hemo/química , Hemoproteínas/química , Porfirinas/química , Cristalografía por Rayos X , Modelos Moleculares , Estructura MolecularRESUMEN
BACKGROUND: Rho GDP dissociation inhibitor 2 (RhoGDI2) has been shown to contribute to the aggressive phenotypes of human cancers, such as tumor metastasis and chemoresistance. OBJECTIVE: This study aimed to assess the effects of RhoGDI2 on tumor progression and chemoresistance in pancreatic cancer cells. METHODS: The expression of RhoGDI2 in pancreatic cancer cells was detected by Western blot analysis. Gain-of-function and loss-of-function approaches were done to examine the malignant phenotypes of the RhoGDI2-expressing or RhoGDI2-depleting cells. The correlation between RhoGDI2 and Snail was also analyzed. RESULTS: Differential expression of RhoGDI2 protein in pancreatic cancer cell lines was identified. Gain-of-function and loss-of-function experiments showed that RhoGDI2 induced the malignant phenotypes of pancreatic cancer cells, including proliferation, migration, invasion, and gemcitabine (GEM) chemoresistance. The upregulation of RhoGDI2 stimulated the expression of Snail, resulting in the altered expression of epithelial marker E-cadherin and mesenchymal marker Vimentin, which were characteristics of the tumorigenic activity of epithelial-mesenchymal transition. The expression of RhoGDI2 and Snail was upregulated in clinical tumor samples, and higher expression of RhoGDI2 or Snail was significantly associated with poor patient survival in pancreatic ductal adenocarcinoma (PDAC). CONCLUSION: The findings indicated that RhoGDI2 promoted GEM resistance and tumor progression in pancreatic cancer and that RhoGDI2 might be a potential therapeutic target in patients with PDAC.