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1.
Proc Natl Acad Sci U S A ; 119(11): e2106053119, 2022 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-35275789

RESUMEN

SignificanceDeep profiling of the plasma proteome at scale has been a challenge for traditional approaches. We achieve superior performance across the dimensions of precision, depth, and throughput using a panel of surface-functionalized superparamagnetic nanoparticles in comparison to conventional workflows for deep proteomics interrogation. Our automated workflow leverages competitive nanoparticle-protein binding equilibria that quantitatively compress the large dynamic range of proteomes to an accessible scale. Using machine learning, we dissect the contribution of individual physicochemical properties of nanoparticles to the composition of protein coronas. Our results suggest that nanoparticle functionalization can be tailored to protein sets. This work demonstrates the feasibility of deep, precise, unbiased plasma proteomics at a scale compatible with large-scale genomics enabling multiomic studies.


Asunto(s)
Proteínas Sanguíneas , Aprendizaje Profundo , Nanopartículas , Proteómica , Proteínas Sanguíneas/química , Nanopartículas/química , Corona de Proteínas/química , Proteoma , Proteómica/métodos
2.
J Am Chem Soc ; 146(9): 5823-5833, 2024 03 06.
Artículo en Inglés | MEDLINE | ID: mdl-38174701

RESUMEN

The biological significance of self-assembled protein filament networks and their unique mechanical properties have sparked interest in the development of synthetic filament networks that mimic these attributes. Building on the recent advancement of autoaccelerated ring-opening polymerization of amino acid N-carboxyanhydrides (NCAs), this study strategically explores a series of random copolymers comprising multiple amino acids, aiming to elucidate the core principles governing gelation pathways of these purpose-designed copolypeptides. Utilizing glutamate (Glu) as the primary component of copolypeptides, two targeted pathways were pursued: first, achieving a fast fibrillation rate with lower interaction potential using serine (Ser) as a comonomer, facilitating the creation of homogeneous fibril networks; and second, creating more rigid networks of fibril clusters by incorporating alanine (Ala) and valine (Val) as comonomers. The selection of amino acids played a pivotal role in steering both the morphology of fibril superstructures and their assembly kinetics, subsequently determining their potential to form sample-spanning networks. Importantly, the viscoelastic properties of the resulting supramolecular hydrogels can be tailored according to the specific copolypeptide composition through modulations in filament densities and lengths. The findings enhance our understanding of directed self-assembly in high molecular weight synthetic copolypeptides, offering valuable insights for the development of synthetic fibrous networks and biomimetic supramolecular materials with custom-designed properties.


Asunto(s)
Hidrogeles , Péptidos , Hidrogeles/química , Péptidos/química , Aminoácidos , Ácido Glutámico/química , Alanina/química
3.
FASEB J ; 36(1): e22121, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34951719

RESUMEN

Protein aggregation and degradation via autophagy (aggrephagy) are major strategies adopted by cells to remove misfolded polypeptides when there is proteasome dysfunction. The functional protein complex consisting of heat shock protein 70 (Hsp70), cochaperone ubiquitin ligase carboxyl-terminal of Hsp70/Hsp90 interacting protein (CHIP), and co-chaperone Bcl-2-associated athanogene 3 (BAG3) has been associated with the activation of protein aggregation. However, data on the mechanisms of action of the complex in the protein degradation remains scant. Here, we report that upon proteasome stress, the M2 isoform of pyruvate kinase (PKM2) promotes the aggregation of ubiquitinated proteins and its knockout or knockdown aggravates the sensitivity of cells to proteasome inhibitors. Besides, following proteasome inhibition, PKM2 promotes the interaction of BAG3 with CHIP and HSP70. Interestingly, re-expression of loss-of-function mutants in PKM2-knockout cells showed that the regulatory function of PKM2 in this progress does not depend on the activity of glycolytic enzymes or protein kinases. Taken together, these findings demonstrate that PKM2 mediates the formation of the CHIP-HSP70-BAG3 protein complex and promotes the aggregation of ubiquitinated misfolded proteins, thus compensating for proteasome stress in cells.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Reguladoras de la Apoptosis/metabolismo , Proteínas HSP70 de Choque Térmico/metabolismo , Complejos Multiproteicos/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Agregado de Proteínas , Piruvato Quinasa/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Proteínas Ubiquitinadas/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Reguladoras de la Apoptosis/genética , Células HEK293 , Proteínas HSP70 de Choque Térmico/genética , Células Hep G2 , Humanos , Complejos Multiproteicos/genética , Complejo de la Endopetidasa Proteasomal/genética , Piruvato Quinasa/genética , Ubiquitina-Proteína Ligasas/genética , Proteínas Ubiquitinadas/genética
4.
Biochem Biophys Res Commun ; 600: 60-66, 2022 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-35193074

RESUMEN

p38δ is a member of p38 mitogen-activated protein kinases (MAPKs) family that displays cell- and tissue-specific expression patterns. Recent studies demonstrate that p38δ is centrally involved in several pathologic events, such as diabetes, neurodegeneration diseases, inflammatory diseases, and cancer, and suggest that it may be a potential target for diagnosis and therapy of specific diseases. A nanobody is a new type of antibody that exhibits high antigen-binding activity, solubility, stability, and easy production. This study utilized phage display to isolate nanobodies specifically against p38δ from a fully synthetic nanobody library. Two of them, nanobodies Nb13-6 and Nb13-1, display high binding activity to p38δ, less cross-reactivity with other p38 MAPKs, and high thermal and pH stabilities. Modeling and docking analysis indicated that Nb13-6 is mostly linked to the activation loop of p38δ. Furthermore, detailed studies revealed that Nb13-6 inhibited the protein kinase activity of p38δ and the growth of cancer cells. Therefore, this study provides p38δ-specific nanobodies that are promisingly exploited for diagnosing and treating p38δ-associated diseases.


Asunto(s)
Proteína Quinasa 14 Activada por Mitógenos , Anticuerpos de Dominio Único , Proteína Quinasa 13 Activada por Mitógenos , Fosforilación , Anticuerpos de Dominio Único/farmacología , Proteínas Quinasas p38 Activadas por Mitógenos
5.
Anticancer Drugs ; 33(9): 935-942, 2022 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-36066403

RESUMEN

Chronic stress has been reported to be associated with tumor initiation and progression. But the underlying mechanism and the specific role of tumor immunity in this process are still unknown. Herein, we applied the repeated restrain stress model in C57BL/6J mice and found that the tumor growth in stressed mice was accelerated compared with that in control mice. In addition, serotonin, also called 5-hydroxytryptamine (5-HT), in the serum of stressed mice was also elevated. Sertraline, a selective serotonin reuptake inhibitor used in the clinic, can restore the serum 5-HT level in stressed mice and restrain tumor growth. We further explored the distribution of major immune cells, including B lymphocytes cells, T lymphocytes, natural killer cells, dendritic cells, tumor-associated macrophages (TAM) and regulatory T cells (Treg). We found that the infiltration of CD8 + T cells in the tumor microenvironment (TME) decreased significantly in stressed mice. And the extra 5-HT treatment could further decrease the infiltration of CD8 + T cells in the TME. The expression of IFN-γ and Granular enzyme B (GzmB) in CD8 + T cells were also dropped in the stressed mice group, whereas the expression of programmed cell death protein 1 (PD-1) on CD8 + T cells was increased. The T cell deficiency induced by stress can be reversed by sertraline, indicating its promising role in strengthening the efficacy of anti-PDL1/PD-1 immunotherapy. The present study provides new mechanistic insights into the impact of chronic stress on antitumor immunity and implicates a novel combined immunotherapy strategy for cancer patients with chronic stress.


Asunto(s)
Receptor de Muerte Celular Programada 1 , Serotonina , Animales , Linfocitos T CD8-positivos , Línea Celular Tumoral , Ratones , Ratones Endogámicos C57BL , Inhibidores Selectivos de la Recaptación de Serotonina , Sertralina/farmacología , Microambiente Tumoral
6.
Biomacromolecules ; 23(1): 196-209, 2022 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-34964619

RESUMEN

In cells, actin and tubulin polymerization is regulated by nucleation factors, which promote the nucleation and subsequent growth of protein filaments in a controlled manner. Mimicking this natural mechanism to control the supramolecular polymerization of macromolecular monomers by artificially created nucleation factors remains a largely unmet challenge. Biological nucleation factors act as molecular scaffolds to boost the local concentrations of protein monomers and facilitate the required conformational changes to accelerate the nucleation and subsequent polymerization. An accelerated assembly of synthetic poly(l-glutamic acid) into amyloid fibrils catalyzed by cationic silica nanoparticle clusters (NPCs) as artificial nucleation factors is demonstrated here and modeled as supramolecular polymerization with a surface-induced heterogeneous nucleation pathway. Kinetic studies of fibril growth coupled with mechanistic analysis demonstrate that the artificial nucleators predictably accelerate the supramolecular polymerization process by orders of magnitude (e.g., shortening the assembly time by more than 10 times) when compared to the uncatalyzed reaction, under otherwise identical conditions. Amyloid-like fibrillation was supported by a variety of standard characterization methods. Nucleation followed a Michaelis-Menten-like scheme for the cationic silica NPCs, while the corresponding anionic or neutral nanoparticles had no effect on fibrillation. This approach shows the effectiveness of charge-charge interactions and surface functionalities in facilitating the conformational change of macromolecular monomers and controlling the rates of nucleation for fibril growth. Molecular design approaches like these inspire the development of novel materials via biomimetic supramolecular polymerizations.


Asunto(s)
Amiloide , Péptidos , Amiloide/química , Proteínas Amiloidogénicas , Cinética , Péptidos/química , Polimerizacion
7.
Mol Cancer ; 20(1): 143, 2021 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-34742312

RESUMEN

Colorectal cancer (CRC) is a heterogeneous disease at the cellular and molecular levels. Kirsten rat sarcoma (KRAS) is a commonly mutated oncogene in CRC, with mutations in approximately 40% of all CRC cases; its mutations result in constitutive activation of the KRAS protein, which acts as a molecular switch to persistently stimulate downstream signaling pathways, including cell proliferation and survival, thereby leading to tumorigenesis. Patients whose CRC harbors KRAS mutations have a dismal prognosis. Currently, KRAS mutation testing is a routine clinical practice before treating metastatic cases, and the approaches developed to detect KRAS mutations have exhibited favorable sensitivity and accuracy. Due to the presence of KRAS mutations, this group of CRC patients requires more precise therapies. However, KRAS was historically thought to be an undruggable target until the development of KRASG12C allele-specific inhibitors. These promising inhibitors may provide novel strategies to treat KRAS-mutant CRC. Here, we provide an overview of the role of KRAS in the prognosis, diagnosis and treatment of CRC.


Asunto(s)
Biomarcadores de Tumor , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/terapia , Oncogenes , Proteínas Proto-Oncogénicas p21(ras)/genética , Neoplasias Colorrectales/metabolismo , Terapia Combinada/efectos adversos , Terapia Combinada/métodos , Manejo de la Enfermedad , Susceptibilidad a Enfermedades , Desarrollo de Medicamentos , Regulación Neoplásica de la Expresión Génica , Humanos , Biopsia Líquida/métodos , Biopsia Líquida/normas , Técnicas de Diagnóstico Molecular , Terapia Molecular Dirigida , Mutación , Pronóstico , Proteínas Proto-Oncogénicas p21(ras)/química , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Sensibilidad y Especificidad , Transducción de Señal , Relación Estructura-Actividad , Resultado del Tratamiento
8.
Cancer Sci ; 112(7): 2664-2678, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33934451

RESUMEN

Immunotherapy targeting the PD-L1/PD-1 pathway is a novel type of clinical cancer treatment, but only small subsets of patients can benefit from it because of multiple factors. PD-L1/PD-1 expression is a biomarker for predicting the efficacy of anti-PD-L1/PD-1 therapy, which highlights the importance of understanding the regulatory mechanisms of PD-L1 expression in cancer cells. Casp8 is an apical caspase protease involved in mediating cell apoptosis, but it also has multiple nonapoptotic functions. Casp8 mutations are associated with increased risks of cancer, and low expression of Casp8 is closely connected with poor prognosis in patients with cancer. In addition, mutations of Casp8 in lymphocytes also lead to human immunodeficiency, thereby causing dysfunction of the innate immune system, but the roles of Casp8 in antitumor immunity remain unclear. Here, we found that knocking down Casp8 in mouse melanoma cells promoted tumor progression in an immune system-dependent manner. Mechanistically, Casp8 induced PD-L1 degradation by upregulating TNFAIP3 (A20) expression, a ubiquitin-editing enzyme that results in PD-L1 ubiquitination. In addition, compared with Casp8fl/fl mice, mice with conditional deletion of Casp8 in natural killer (NK) cells (Ncr1iCre/+ Casp8fl/fl mice) showed a decreased frequency of IFN-γ+ and CD107a+ NK cells but an increased frequency of PD-1+ and CTLA-4+ NK cells. Melanoma cells with Casp8 knocked down exhibited sensitivity to anti-PD-1 or anti-CTLA-4 antibody treatments, particularly in Ncr1iCre/+Casp8fl/fl mice. Together, the results indicate that Casp8 induces PD-L1 degradation by upregulating A20 expression and that decreased Casp8 expression is a potential biomarker for predicting the sensitivity to anti-PD-L1/PD-1 immunotherapy.


Asunto(s)
Antígeno B7-H1/metabolismo , Caspasa 8/fisiología , Inmunoterapia Adoptiva/métodos , Melanoma/terapia , Proteína 3 Inducida por el Factor de Necrosis Tumoral alfa/metabolismo , Animales , Antígeno B7-H1/genética , Antígeno CTLA-4/metabolismo , Caspasa 8/genética , Línea Celular Tumoral , Progresión de la Enfermedad , Regulación hacia Abajo , Proteínas Activadoras de GTPasa/metabolismo , Interferón gamma/metabolismo , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/metabolismo , Proteínas de Membrana de los Lisosomas/metabolismo , Melanoma/inmunología , Melanoma/patología , Ratones , Ratones Endogámicos C57BL , Ratones Desnudos , FN-kappa B/metabolismo , Ubiquitinación , Regulación hacia Arriba
9.
Cancer Cell Int ; 21(1): 166, 2021 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-33712026

RESUMEN

BACKGROUND: Tumor metastasis is one of the leading reasons of the dismal prognosis of hepatocellular carcinoma (HCC). Epithelial-mesenchymal transition (EMT) is closely associated with tumor metastasis including HCC. The purpose of this study is to construct and validate an EMT-related gene signature for predicting the prognosis of HCC patients. METHODS: Gene expression data of HCC patients was downloaded from The Cancer Genome Atlas (TCGA) database. Gene set enrichment analysis (GSEA) was performed to found the EMT-related gene sets which were obviously distinct between normal samples and paired HCC samples. Cox regression analysis was used to develop an EMT-related prognostic signature, and the performance of the signature was evaluated by Kaplan-Meier curves and time-dependent receiver operating characteristic (ROC) curves. A nomogram incorporating the independent predictors was established. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression levels of the hub genes in HCC cell lines, and the role of PDCD6 in the metastasis of HCC was determined by functional experiments. RESULTS: An EMT-related 5-gene signature (PDCD6, TCOF1, TRIM28, EZH2 and FAM83D) was constructed using univariate and multivariate Cox regression analysis. Based on the signature, the HCC patients were classified into high- and low-risk groups, and patients in high-risk group had a poor prognosis. Time-dependent ROC and Cox regression analyses suggested that the signature could predict HCC prognosis exactly and independently. The predictive capacity of the signature was also validated in two external cohorts. GSEA results showed that many cancer-related signaling pathways such as PI3K/Akt/mTOR pathway and TGF-ß/SMAD pathway were enriched in high-risk group. The result of qRT-PCR revealed that PDCD6, TCOF1 and FAM83D were highly expressed in HCC cancer cells. Among them, PDCD6 were found to promote cell migration and invasion. CONCLUSION: The EMT-related 5-gene signature can serve as a promising prognostic biomarker for HCC patients and may provide a novel mechanism of HCC metastasis.

10.
Macromol Rapid Commun ; 42(8): e2000677, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33522026

RESUMEN

Inspired by protein polymerizations, much progress has been made in making "polymer-like" supramolecular structures from small synthetic subunits through non-covalent bonds. A few regulation mechanisms have also been explored in synthetic platforms to create supramolecular polymers and materials with dynamic properties. Herein, a type of reactive regulator that facilitates the dimerization of the monomer precursors through dynamic bonds to trigger the supramolecular assembly from small molecules in an aqueous solution is described. The supramolecular structures are crystalline in nature and the reaction coupled assembly strategy can be extended to a supramolecular assembly of aromatic amide derivatives formed in-situ. The method may be instructive for the development of supramolecular nanocrystalline materials with desired physical properties.


Asunto(s)
Compuestos Heterocíclicos , Polímeros , Sustancias Macromoleculares , Polimerizacion , Agua
11.
J Cell Mol Med ; 24(5): 3167-3182, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31991051

RESUMEN

OBJECTIVES: Investigation of mechanism related to excessive invasion of trophoblast cells in placenta accreta spectrum disorders (PAS) provides more strategies and ideas for clinical diagnosis and treatment. MATERIALS AND METHODS: Blood and placental samples were collected from included patients. The distribution and expression of CXCL12, CXCR4 and CXCR7 proteins in the paraffin of placental tissue in the included cases were analysed, and we analyse the downstream pathways or key proteins involved in cell invasion. RESULTS: Firstly, our results determined that CXCL12 and CXCR4/CXCR7 were increased in extravillous trophoblastic cell (CXCL12: P < .001; CXCR4: P < .001; CXCR7: P < .001), and the expression levels were closely related to the invasion depth of trophoblastic cells. Secondly, CXCL12 has the potential to become a biochemical indicator of PAS since the high expression of placental trophoblast CXCL12 may be an important source of blood CXCL12. Using lentivirus-mediated RNA interference and overexpression assay, it was found that both chemokine CXCL12 and receptor CXCR4/CXCR7 are associated with regulation of trophoblast cell proliferation, migration and invasion. Further results proved that through the activating the phosphorylation and increasing the expression of MLC and AKT proteins in the Rho/rock, PI3K/AKT signalling pathway, CXCL12, CXCR4 and CXCR7 could up-regulate the expression of RhoA, Rac1 and Cdc42 proteins to promote the migration and invasion of extravillous trophoblastic cell and ultimately formate the placenta accrete compare to the normal placenta. CONCLUSIONS: Our research proved that trophoblasts may contribute to a PAS-associated increase in CXCL12 levels in maternal blood. CXCL12 is not only associated with biological roles of PAS, but may also be potential for prediction of PAS.


Asunto(s)
Quimiocina CXCL12/sangre , Enfermedades Placentarias/sangre , Receptores CXCR4/sangre , Receptores CXCR/sangre , Adulto , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Quimiocina CXCL12/genética , Femenino , Regulación de la Expresión Génica/genética , Humanos , Fosforilación/genética , Placenta Accreta/patología , Enfermedades Placentarias/genética , Enfermedades Placentarias/patología , Embarazo , Receptores CXCR/genética , Receptores CXCR4/genética , Trofoblastos/metabolismo , Trofoblastos/patología
12.
J Cell Physiol ; 235(1): 221-231, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31187497

RESUMEN

The motility of mesenchymal stem cells (MSCs) is highly related to their homing in vivo, a critical issue in regenerative medicine. Our previous study indicated copper (Cu) might promote the recruitment of endogenous MSCs in canine esophagus defect model. In this study, we investigated the effect of Cu on the motility of bone marrow mesenchymal stem cells (BMSCs) and the underlying mechanism in vitro. Cu supplementation could enhance the motility of BMSCs, and upregulate the expression of hypoxia-inducible factor 1α (Hif1α) at the protein level, and upregulate the expression of rho family GTPase 3 (Rnd3) at messenger RNA and protein level. When Hif1α was silenced by small interfering RNA (siRNA), Cu-induced Rnd3 upregulation was blocked. When Rnd3 was silenced by siRNA, the motility of BMSCs was decreased with or without Cu supplementation, and Cu-induced cytoskeleton remodeling was neutralized. Furthermore, overexpression of Rnd3 also increased the motility of BMSCs and induced cytoskeleton remodeling. Overall, our results demonstrated that Cu enhanced BMSCs migration through, at least in part, cytoskeleton remodeling via Hif1α-dependent upregulation of Rnd3. This study provided an insight into the mechanism of the effect of Cu on the motility of BMSCs, and a theoretical foundation of applying Cu to improve the recruitment of BMSCs in tissue engineering and cytotherapy.


Asunto(s)
Movimiento Celular/efectos de los fármacos , Cobre/farmacología , Citoesqueleto/metabolismo , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/fisiología , Proteínas de Unión al GTP rho/metabolismo , Animales , Regulación de la Expresión Génica/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Regulación hacia Arriba , Proteínas de Unión al GTP rho/genética
13.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 35(1): 81-86, 2018 02 25.
Artículo en Zh | MEDLINE | ID: mdl-29745605

RESUMEN

The aim of this article is to study the regulatory feedback loop between ß-catenin and IQ motif containing GTPase activating protein 1 (IQGAP1), as well as the effect of this regulation loop in colon cancer cell proliferation. Western blot was used to detect the expression of IQGAP1 and ß-catenin after changing their expression respectively by transfection in SW1116 cells. CCK-8 cell proliferation assay was used to detect the effect of IQGAP1 involved in the proliferation of SW1116 cells promoted by ß-catenin. The results of Western blot indicated that ß-catenin could positively regulate IQGAP1, while IQGAP1 silencing could up-regulate ß-catenin, forming a negative feedback loop. The results of CCK-8 showed that IQGAP1 silencing inhibited ß-catenin-mediated proliferation in SW1116 cells. In conclusion, our research reveals a negative regulatory feedback loop between ß-catenin and IQGAP1 which has a remarkable effect on the proliferation ability of colon cancer cells.

14.
J Am Chem Soc ; 139(32): 11106-11116, 2017 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-28776987

RESUMEN

Supramolecular polymerization or assembly of proteins or large macromolecular units by a homogeneous nucleation mechanism can be quite slow and require specific solution conditions. In nature, protein assembly is often regulated by molecules that modulate the electrostatic interactions of the protein subunits for various association strengths. The key to this regulation is the coupling of the assembly process with a reversible or irreversible chemical reaction that occurs within the constituent subunits. However, realizing this complex process by the rational design of synthetic molecules or macromolecules remains a challenge. Herein, we use a synthetic polypeptide-grafted comb macromolecule to demonstrate how the in situ modulation of interactions between the charged macromolecules affects their resulting supramolecular structures. The kinetics of structural formation was studied and can be described by a generalized model of nucleated polymerization containing secondary pathways. Basic thermodynamic analysis indicated the delicate role of the electrostatic interactions between the charged subunits in the reaction-induced assembly process. This approach may be applicable for assembling a variety of ionic soft matters that are amenable to chemical reactions in situ.

15.
Tumour Biol ; 35(1): 387-96, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23929390

RESUMEN

There have been many trials trying to prove the benefit of radiotherapy for gastric cancer; however, the results were either inclusive or controversial. The purpose of the study was to elucidate the effect of radiotherapy on gastric cancer delivered as perioperative or palliative treatment. We conducted systematic searches for trials exploring the effect of radiotherapy on gastric cancer. In the subgroup of patients receiving preoperative radiotherapy for gastric cancer, a significant benefit was found on 10-year overall survival with a hazard ratio (HR) of 0.75 (95% confidence interval (CI), 0.61 to 0.91); however, the benefit on 5-year overall survival was not proven (HR, 0.68; 95%CI, 0.45 to 1.01). There are also no significant differences in resection rate and radical resection rate between group of patients receiving radiotherapy and control group with a relative risk (RR) of 1.06 (95%CI, 0.99 to 1.13) and 1.12 (95%CI 0.93 to 1.36), respectively. In the subgroup of patients receiving postoperative radiotherapy for gastric cancer, survival benefits were found on 3- and 5-year progression-free survival with HR of 0.69 (95%CI, 0.53 to 0.90) and HR of 0.70 (95%CI, 0.61 to 0.80), respectively. Survival benefits of adjuvant radiotherapy on 3- and 5-year progression-free survival were also found; nonetheless, there was no evidence of significant difference in 3-year overall survival (HR, 0.70; 95%CI, 0.61 to 1.01). The effect of radiotherapy on 5-year overall survival was also quite controversial. In short, gastric cancer patients could benefit from radiotherapy both in the form of preoperative radiotherapy and postoperative radiotherapy.


Asunto(s)
Neoplasias Gástricas/radioterapia , Quimioterapia Adyuvante , Humanos , Periodo Posoperatorio , Radioterapia Adyuvante , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/terapia
16.
Acta Pharm Sin B ; 14(5): 1895-1923, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38799634

RESUMEN

RAS mutations occur in approximately 30% of tumors worldwide and have a poor prognosis due to limited therapies. Covalent targeting of KRAS G12C has achieved significant success in recent years, but there is still a lack of efficient therapeutic approaches for tumors with non-G12C KRAS mutations. A highly promising approach is to target the MAPK pathway downstream of RAS, with a particular focus on RAF kinases. First-generation RAF inhibitors have been authorized to treat BRAF mutant tumors for over a decade. However, their use in RAS-mutated tumors is not recommended due to the paradoxical ERK activation mainly caused by RAF dimerization. To address the issue of RAF dimerization, type II RAF inhibitors have emerged as leading candidates. Recent clinical studies have shown the initial effectiveness of these agents against RAS mutant tumors. Promisingly, type II RAF inhibitors in combination with MEK or ERK inhibitors have demonstrated impressive efficacy in RAS mutant tumors. This review aims to clarify the importance of RAF dimerization in cellular signaling and resistance to treatment in tumors with RAS mutations, as well as recent progress in therapeutic approaches to address the problem of RAF dimerization in RAS mutant tumors.

17.
Transl Cancer Res ; 13(6): 3003-3015, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38988934

RESUMEN

Background: Adjuvant chemotherapy (ACT) is a well-recognized and well-established treatment for surgically resected non-small cell lung cancer (NSCLC), but its suitability for elderly patients remains controversial. Further investigation is warranted to guide ACT decisions in this demographic. Methods: We extracted data from the Surveillance, Epidemiology, and End Results (SEER) database, focusing on patients aged 70 years or older who underwent surgical resection for stage IB, II, or III NSCLC as per the 7th edition of the American Joint Committee on Cancer staging system (AJCC 7th edition). Propensity score matching (PSM), Kaplan-Meier analysis, and Cox regression were employed for statistical analyses. Results: There were 503 participants received ACT in this study of 2,000 patients aged 70 or older with stage IB-IIIB NSCLC who underwent surgical resection without preoperative chemotherapy. Overall, ACT did not significantly correlate with extended overall survival (OS) (P=0.07) compared to non-ACT. After 2:1 PSM, the matched cohort comprised 317 non-ACT and 206 ACT recipients. Post-PSM, the ACT group exhibited improved OS (P=0.044) compared to the non-ACT group. Cox regression analysis identified gender, primary tumor site, histologic grade, N stage, and ACT as independent predictors of OS (P<0.05). Subgroup analysis indicated amplified ACT benefits in individuals aged 70-79 years, male, with N1 stage, or those without radiotherapy. Conclusions: ACT may confer benefits to elderly stage IB-IIIB NSCLC patients, particularly those aged 70-79 years, male, and with N1 stage.

18.
NPJ Biofilms Microbiomes ; 10(1): 5, 2024 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-38245554

RESUMEN

A high-fat diet (HFD) may be linked to an increased colorectal cancer (CRC) risk. Stem cell proliferation and adipokine release under inflammatory and obese conditions are the main factors regulating CRC progression. Furthermore, alterations in intestinal flora have been linked to tumorigenesis and tumour progression. However, whether a HFD can promote CRC occurrence by altering intestinal flora remains unclear. The objective of this study was to identify bacterial strains enriched by a HFD and investigate the association and mechanism by which a HFD and bacterial enrichment promote CRC occurrence and development. In this study, the intestinal microbiota of mice was assessed using 16S rRNA and metagenomic sequencing. Serum metabolites of HFD-fed mice were assessed using tandem liquid chromatography-mass spectrometry. CRC cell lines and organoids were co-cultured with Coriobacteriaceae to evaluate the effect of these bacteria on the CPT1A-ERK signalling pathway. We found that Coriobacteriaceae were enriched in the colons of HFD-fed mice. An endogenous Coriobacteriaceae strain, designated as Cori.ST1911, was successfully isolated and cultured from the stools of HFD-fed mice, and the tumorigenic potential of Cori.ST1911 in CRC was validated in several CRC mouse models. Furthermore, Cori.ST1911 increased acylcarnitine levels by activating CPT1A, demonstrating the involvement of the CPT1A-ERK axis. We also found that the endogenous Lactobacillus strain La.mu730 can interfere with Cori.ST1911 colonisation and restore gut barrier function. In conclusion, we identified a novel endogenous intestinal Coriobacteriaceae, Cori.ST1911, which might lead to a new gut microbiota intervention strategy for the prevention and treatment of CRC.


Asunto(s)
Neoplasias Colorrectales , Microbioma Gastrointestinal , Ratones , Animales , Dieta Alta en Grasa/efectos adversos , ARN Ribosómico 16S/genética , Carcinogénesis , Microbioma Gastrointestinal/fisiología , Neoplasias Colorrectales/etiología
19.
J Am Chem Soc ; 135(31): 11417-20, 2013 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-23697509

RESUMEN

Controlled assembly of inorganic nanoparticles (NPs) into structurally defined supramolecular polymers will create nanomaterials with new collective properties. However, supramolecular polymerization of isotropic NPs remains a challenge because of the lack of anisotropic interactions in these monomers to undergo directional associations for the cooperative growth of supramolecular chains. Herein we report self-assembly behavior of poly(l-glutamic acid)-grafted gold NPs in solution and describe how combined attractive and repulsive interactions influence the shape and size of the resulting supramolecular assemblies. The study shows that the chain growth of supramolecular polymers can be achieved from the NP monomers and the process occurs in two distinct stages, with a slow nucleation step followed by a faster chain propagation step. The resulting supramolecular structures depend on both the grafting density of the poly(l-glutamic acid) on the NPs and the size of the NPs.


Asunto(s)
Oro/química , Nanopartículas/química , Ácido Poliglutámico/química , Polimerizacion , Modelos Moleculares , Nanopartículas/ultraestructura , Tamaño de la Partícula
20.
Transl Cancer Res ; 12(10): 2742-2753, 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37969392

RESUMEN

Background: There is variability in the prognosis of stage III-N2 lung adenocarcinoma (LUAD) patients. The current tumor-node-metastasis (TNM) staging is not sufficient to precisely estimate the prognosis of stage III-N2 LUAD patients. The Surveillance, Epidemiology, and End Results (SEER) database collected first-hand information from a large number of LUAD patients. Based on the SEER database, this study aimed to determine the prognostic factors that affect overall survival (OS) in stage III-N2 LUAD patients and then establish a nomogram for predicting OS in this type of cancer to identify the high-risk population that may require more frequent surveillance or intensive care. Methods: Data for 1,844 stage III-N2 primary LUAD patients who were registered between 2010 and 2015 were obtained from the SEER database. These patients were randomly assigned to either training (n=1,290) or validation (n=554) cohorts at a 7:3 ratio. The univariate and multivariate Cox regression (UCR and MCR) analyses were performed to find the relevant independent prognostic factors. To predict the OS based on these prognostic factors, a nomogram was then developed. The performance of the nomogram was examined based on the calibration curves, and receiver operating characteristic (ROC) curves. The ability of nomogram to stratify patient risk was validated by Kaplan-Meier survival analysis. Results: Age, gender, tumor location, T-stage and treatment modality (chemotherapy, radiation therapy, surgery and scope of lymph node dissection) of stage III-N2 LUAD patients were significantly associated with prognosis. The area under the curve (AUC) values of OS predicted by the nomogram constructed with these factors at 12-, 36- and 60-month were 0.784, 0.762 and 0.763 in the training cohort, whereas 0.707, 0.685 and 0.705 in the validation cohort, respectively. Additionally, calibration curves demonstrated concordance between predicted and observed outcomes. Nomogram risk stratification provides a meaningful distinction between patients with various survival risks. Conclusions: A survival prediction model that may be useful for risk stratification and decision-making is developed and validated for stage III-N2 LUAD patients. A high-risk patient predicted by the prediction model may require more frequent surveillance or intensive care.

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