RESUMO
OBJECTIVES: Detection of early neoplastic lesions is crucial for improving the survival rates of patients with gastric cancer. Optical enhancement mode 2 is a new image-enhanced endoscopic technique that offers bright images and can improve the visibility of neoplastic lesions. This study aimed to compare the detection of neoplastic lesions with optical enhancement mode 2 and white-light imaging (WLI) in a high-risk population. METHODS: In this prospective multicenter randomized controlled trial, patients were randomly assigned to optical enhancement mode 2 or WLI groups. Detection of suspicious neoplastic lesions during the examinations was recorded, and pathological diagnoses served as the gold standard. RESULTS: A total of 1211 and 1219 individuals were included in the optical enhancement mode 2 and WLI groups, respectively. The detection rate of neoplastic lesions was significantly higher in the optical enhancement mode 2 group (5.1% vs. 1.9%; risk ratio, 2.656 [95% confidence interval, 1.630-4.330]; p < 0.001). The detection rate of neoplastic lesions with an atrophic gastritis background was significantly higher in the optical enhancement mode 2 group (8.6% vs. 2.6%, p < 0.001). The optical enhancement mode 2 group also had a higher detection rate among endoscopists with different experiences. CONCLUSIONS: Optical enhancement mode 2 was more effective than WLI for detecting neoplastic lesions in the stomach, and can serve as a new method for screening early gastric cancer in clinical practice. CLINICAL REGISTRY: United States National Library of Medicine (https://www. CLINICALTRIALS: gov), ID: NCT040720521.
Assuntos
Detecção Precoce de Câncer , Gastroscopia , Aumento da Imagem , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/patologia , Neoplasias Gástricas/diagnóstico , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Prospectivos , Gastroscopia/métodos , Detecção Precoce de Câncer/métodos , Idoso , Aumento da Imagem/métodos , Gastrite Atrófica/diagnóstico , Gastrite Atrófica/patologia , Gastrite Atrófica/diagnóstico por imagem , AdultoRESUMO
AIM: To investigate the mechanism of calcyclin binding protein/Siah-1 interacting protein (CacyBP/SIP) nuclear translocation in promoting the proliferation of gastric cancer (GC) cells. METHODS: The effect of CacyBP/SIP nuclear translocation on cell cycle was investigated by cell cycle analysis. Western blot analysis was used to assess the change in expression of cell cycle regulatory proteins and proteasome-mediated degradation of p27Kip1. Co-immunoprecipitation (co-IP) analysis was performed to examine the binding of CacyBP/SIP with Skp1. A CacyBP/SIP truncation mutant which lacked the Skp1 binding site was constructed and fused to a fluorescent protein. Subsequently, the effect on Skp1 binding with the fusion protein was examined by co-IP, while localization of fluorescent fusion protein observed by confocal laser microscopy, and change in p27Kip1 protein expression assessed by Western blot analysis. RESULTS: CacyBP/SIP nuclear translocation induced by gastrin promoted progression of GC cells from G1 phase. However, while CacyBP/SIP nuclear translocation was inhibited using siRNA to suppress CacyBP/SIP expression, cell cycle was clearly inhibited. CacyBP/SIP nuclear translocation significantly decreased the level of cell cycle inhibitor p27Kip1, increased Cyclin E protein expression whereas the levels of Skp1, Skp2, and CDK2 were not affected. Upon inhibition of CacyBP/SIP nuclear translocation, there were no changes in protein levels of p27Kip1 and Cyclin E, while p27Kip1 decrease could be prevented by the proteasome inhibitor MG132. Moreover, CacyBP/SIP was found to bind to Skp1 by immunoprecipitation, an event that was abolished by mutant CacyBP/SIP, which also failed to stimulate p27Kip1 degradation, even though the mutant could still translocate into the nucleus. CONCLUSION: CacyBP/SIP nuclear translocation contributes to the proliferation of GC cells, and CacyBP/SIP exerts this effect, at least in part, by stimulating ubiquitin-mediated degradation of p27Kip1.
Assuntos
Adenocarcinoma/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Neoplasias Gástricas/metabolismo , Transporte Ativo do Núcleo Celular , Adenocarcinoma/genética , Adenocarcinoma/patologia , Proteínas de Ligação ao Cálcio/genética , Linhagem Celular Tumoral , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p27/genética , Pontos de Checagem da Fase G1 do Ciclo Celular , Humanos , Complexo de Endopeptidases do Proteassoma/metabolismo , Ligação Proteica , Estabilidade Proteica , Proteólise , Interferência de RNA , Proteínas Ligases SKP Culina F-Box/metabolismo , Transdução de Sinais , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Transfecção , UbiquitinaçãoRESUMO
AIM: To investigate the role of nuclear translocation of calcyclin binding protein, also called Siah-1 interacting protein (CacyBP/SIP), in gastric carcinogenesis. METHODS: The expression of CacyBP/SIP protein in gastric cancer cell lines was detected by Western blot. Immunofluorescence experiments were performed on gastric cancer cell lines that had been either unstimulated or stimulated with gastrin. To confirm the immunofluorescence findings, the relative abundance of CacyBP/SIP in nuclear and cytoplasmic compartments was assessed by Western blot. The effect of nuclear translocation of CacyBP/SIP on cell proliferation was examined using MTT assay. The colony formation assay was used to measure clonogenic cell survival. The effect of CacyBP/SIP nuclear translocation on cell cycle progression was investigated. Two CacyBP/SIP-specific siRNA vectors were designed and constructed to inhibit CacyBP/SIP expression in order to reduce the nuclear translocation of CacyBP/SIP, and the expression of CacyBP/SIP in stably transfected cells was determined by Western blot. The effect of inhibiting CacyBP/SIP nuclear translocation on cell proliferation was then assessed. RESULTS: CacyBP/SIP protein was present in most of gastric cancer cell lines. In unstimulated cells, CacyBP/SIP was distributed throughout the cytoplasm; while in stimulated cells, CacyBP/SIP was found mainly in the perinuclear region. CacyBP/SIP nuclear translocation generated a growth-stimulatory effect on cells. The number of colonies in the CacyBP/SIP nuclear translocation group was significantly higher than that in the control group. The percentage of stimulated cells in G1 phase was significantly lower than that of control cells (69.70% ± 0.46% and 65.80% ± 0.60%, control cells and gastrin-treated SGC7901 cells, P = 0.008; 72.99% ± 0.46% and 69.36% ± 0.51%, control cells and gastrin-treated MKN45 cells, P = 0.022). CacyBP/SIPsi1 effectively down-regulated the expression of CacyBP/SIP, and cells stably transfected by CacyBP/SIPsi1 were then chosen for further cellular assays. In CacyBP/SIPsi1 stably transfected cells, CacyBP/SIP was shown to be distributed throughout the cytoplasm, irregardless of whether they were stimulated or not. After CacyBP/SIP nuclear translocation was reduced, there had no major effect on cell proliferation, as shown by MTT assay. There had no enhanced anchorage-dependent growth upon stimulation, as indicated by colony formation in flat plates. No changes appeared in the percentage of cells in G0-G1 phase in either cell line (71.09% ± 0.16% and 70.86% ± 0.25%, control cells and gastrin-treated SGC7901-CacyBP/SIPsi1 cells, P = 0.101; 74.17% ± 1.04% and 73.07% ± 1.00%, control cells and gastrin-treated MKN45-CacyBP/SIPsi1 cells, P = 0.225). CONCLUSION: CacyBP/SIP nuclear translocation promotes the proliferation and cell cycle progression of gastric cancer cells.
Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Núcleo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Gastrinas/farmacologia , Neoplasias Gástricas/metabolismo , Transporte Ativo do Núcleo Celular , Proteínas de Ligação ao Cálcio/genética , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Núcleo Celular/patologia , Relação Dose-Resposta a Droga , Humanos , Interferência de RNA , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Fatores de Tempo , TransfecçãoRESUMO
PURPOSE: Carbamylation, an important post-translational modification of proteins, inevitably causes conformational changes of lens proteins. It may increase aggregation between crystallin molecules and disrupt the close packing required for transparency thus leading to cataract. The aim of this study was to isolate the primary targets of carbamylation in the lens and identify them by mass spectrometry. MATERIALS AND METHODS: Fresh intact bovine lenses were incubated with 100 mM potassium cyanate for 7 days. The proteins in the water-soluble fractions from the normal control and the cyanate-modified lens proteins were separated by two-dimensional (2-D) gel electrophoresis with identification after silver staining. Protein spots that differed between the normal and carbamylated groups were selected for further analysis using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS). RESULTS: The 2-D gel results showed that the major lens proteins were in the section of pI 5-8, with relative molecular masses of 20-35 kDa, and changes in the carbamylated fraction like strings of beads indicating modification. The mass spectrometry analysis and a database search identified carbamylated proteins originating from alphaA-crystallin, betaB2- and gammaS-(betaS)-crystallins. CONCLUSIONS: These crystallins may be vulnerable proteins targeted by carbamylation. The accumulated aggregation and loss of chaperone activity may contribute to cataract formation.
Assuntos
Cristalino/metabolismo , Espectrometria de Massas , Processamento de Proteína Pós-Traducional , Cadeia A de alfa-Cristalina/metabolismo , Cadeia B de beta-Cristalina/metabolismo , Animais , Bovinos , Eletroforese em Gel Bidimensional , Técnicas In Vitro , Peso Molecular , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Cadeia A de alfa-Cristalina/química , Cadeia B de beta-Cristalina/química , gama-Cristalinas/química , gama-Cristalinas/metabolismoRESUMO
AIM: To investigate the effect of firing noise on gastrointestinal transit and probe its mechanism by measuring the levels of plasma polypeptide hormones. METHODS: A total of 64 SD rats were randomly divided into a control group and three stimulating groups. Firing noise of different intensity by sub-machine guns was used as inflicting factor. The effect of firing noise on liquid substance gastrointestinal transit and solid substance gastrointestinal transit was observed by measuring the ratio of carbon powder suspension transmitting and barium sticks transmitting respectively. Plasma levels of polypeptide hormones were measured by radio-immunoassay. RESULTS: The noise accelerated gastrointestinal transit of solid food by more than 80 db;and accelerated gastrointestinal transit of liquid food significantly by more than 120 db. Meantime, plasma levels of plasma motilin (MTL)(157.47+/-16.08; 151.90+/-17.08), somatostatin (SS)(513.97+/-88.77; 458.25+/-104.30), substance P (SP)(115.52+/-20.70; 110.28+/-19.96) and vasoactive intestinal peptide (VIP) (214.21+/-63.17; 251.76+/-97.24) remarkably changed also. CONCLUSION: Within a certain intensity range, the firing noise changes the levels of rat plasma gastrointestinal hormones, but the gastrointestinal transit is still normal. Beyond the range, the noise induces plasma hormone levels disturbance and gastrointestinal transit disorder.
Assuntos
Hormônios Gastrointestinais/sangue , Trânsito Gastrointestinal , Ruído , Hormônios Peptídicos/sangue , Animais , Explosões , Ratos , Ratos Sprague-DawleyRESUMO
OBJECTIVE: To evaluate the preventive potential of intraoperative or early postoperative local administration of peptide PIII into the abdominal cavity against peritoneal carcinomatosis. METHODS: Human gastric cancer cells of the line GC9811 were inoculated subcutaneously into nude mice to cause subcutaneous carcinoma. The 8th generation cancer was taken out to isolate the cancer cells to be inoculated into the serous membrane at the greater curvature of the stomach. Forty-eight nude BALB/C-nu/nu mice underwent implantation of the 8th generation cancer cells into the serous membrane at the greater curvature of the stomach via minilaparotomy so as to establish models of peritoneal carcinoma The 48 mice were randomly divided into 3 equal groups: Group 1 (control group); Group 2, undergoing intraperitoneal perfusion of 100 microg of peptide PIII, and post-operative intraperitoneal perfusion of 2 mg/kg peptide PIII twice; and Group 3, undergoing post-operative intraperitoneal perfusion of 100 microg/kg peptide PIII twice. Six mice in every group were sacrificed on the day 23 to undergo pathological examination. The other mice in every group were used to evaluate the survival rate. The tumor-bearing mice showing manifestations of failure were killed to undergo pathology. RESULTS: The weight of individual tumor was not significantly different among the 3 groups. The number of peritoneal metastatic nodules of Group 2 was (9.2 +/- 1.3), significantly less than those of Group 1 and 3 [(126.3 +/- 9.6) and (64.2 +/- 8.3) respectively, both P < 0.01]. The number of metastatic nodules > 2 mm of Group 2 was 1.6 +/- 0.2, significantly less then those of Groups 1 and 3 [(51.2 +/- 3.6) and (21.7 +/- 4.9) respectively, both P < 0.01]. The survival rate of Group 2 was significantly longer than those of Groups 1 and 3 (both P < 0.01). CONCLUSION: Peptide PIII does not significantly inhibit the growth of GC, but significantly reduce the peritoneal metastasis of GC. An ideal targeting chemotherapy, intra-operative application of peptide PIII into the abdominal cavity plus intraperitoneal perfusion is an attractive and promising strategy to prevent peritoneal metastasis of GC.