Proteomic characterization of the cytotoxic mechanism of gold (III) porphyrin 1a, a potential anticancer drug

There has been increasing interest in the potential applications of gold (III) complexes as anticancer drugs with higher cytotoxicity and fewer side effects than existing metal anticancer drugs. Our previous findings demonstrated that gold (III) porphyrin la preferentially induced apoptosis in a cancer cell line (SUNE1). In this study, we identified differentially expressed proteins related to the drug's cytotoxic action by comparing the protein alterations induced by gold (III) porphyrin la and cisplatin treatments. Several clusters of altered proteins were identified, including cellular structure and stress-related chaperone proteins, proteins involved in reactive oxygen species and enzyme proteins, translation factors, proteins that mediate cell proliferation or differentiation, and proteins participating in the internal degradation systems. Our results indicated that multiple factors leading to apoptosis were involved in drug cytotoxicity in SUNE1 cells. The balance between pro-apoptotic and anti-apoptotic signals determined the final fate of cancer cells. © 2006 Wiley-VCH Verlag GmbH & Co. KGaA.postprin

Comparative proteomic analysis of esophageal squamous cell carcinoma

Ranking as the fourth commonest cancer, esophageal squamous cell carcinoma (ESCC) represents one of the leading causes of cancer death in China. One of the main reasons for the low survival rate is that neoplasms in esophagus are not detected until they have invaded into surrounding tissues or spread throughout the body at advanced stages. A better understanding of the malignant mechanism and early diagnosis are important for fighting ESCC. In this study, we used proteomics to analyze ESCC tissues, aiming at defining the proteomic features implicated in the multistage progression of esophageal carcinogenesis. Proteins that exhibited significantly different expressions were identified by peptide mass fingerprinting and validated by Western blotting and reverse transcriptase-polymerase chain reaction. The protein changes were then correlated to the different grades of disease differentiation. Compared to those in adjacent normal epitheliums, the expression of 15 proteins including enolase, elongation factor Tu, isocitrate dehydrogenase, tubulin alpha-1 chain, tubulin beta-5 chain, actin (cytoplasmic 1), glyceraldehyde-3 phosphate dehydrogenase, tropomyosin isoform 4 (TPM4), prohibitin, peroxiredoxin 1 (PRX1), manganese-containing superoxide dismutase (MnSOD), neuronal protein, and transgelin was up-regulated; and the expression of five proteins including TPM1, squamous cell carcinoma antigen 1 (SCCA1), stratifin, peroxiredoxin 2 isoform a, and alpha B crystalline was down-regulated in cancer tissues with a statistical significance (p < 0.05). In addition, the differential expression of SCCA1, PRX1, MnSOD, TPM4, and prohibitin can be observed in precancerous lesions of ESCC. The expression of stratifin, prohibitin, and SCCA1 dropped with increasing dedifferentiation of ESCC. These data may suggest that these proteins contribute to the multistage process of carcinogenesis, tumor progression, and invasiveness of ESCC. © 2005 WILEY-VCH Verlag GmbH & Co. KGaA.postprin

Diverse proteomic alterations in gastric adenocarcinoma

Gastric adenocarcinoma is one of the most common cancers in Asian countries including China. Although its incidence rates in the West are lower than that in Asia, gastric cancer is still a major health problem worldwide, being second only to lung cancers in the number of deaths it causes. Helicobacter pylori infection has been identified as the major pathogen, but the detailed pathogenesis of gastric carcinoma remains elusive. Due to the lack of suitable and specific biomarkers for early detection, most cases of the disease are diagnosed at late stages and the survival rate is low. In this study, we used a proteomic approach to globally analyze the protein profiles of paired surgical specimens of primary gastric adenocarcinoma and nontumor mucosa aiming at identifying specific disease-associated proteins as potential clinical biomarkers and for carcinogenetic study. Compared to nontumor tissues, multiple protein alterations were found in tumor tissues. Some of these alterations involve variations in the expression of cytoskeleton proteins, including an increase in cytokeratin 8 and tropomyosin isoform and a decrease in cytokeratin 20. Co-up-regulations of heat-shock proteins and glycolytic enzymes were observed in tumor tissues, indicating self-protective efforts of cells and the growing energy requirement during malignant transformation. Diverse regulations also occurred with proteins involved in cell proliferation and differentiation, such as GMP reductase 2 and creatine kinase B, and proteins bearing potential tumor suppressor activities, including prohibitin and selenium binding protein 1. More interestingly, a human stomach-specific protein, 18 kDa antrum mucosa protein, was found to be dramatically under-expressed in cancer tissues, implicating a possible special pathological role for this protein in gastric carcinogenesis. Further comprehensive evaluation by globally considering the altered factors may result in the discovery of a biomarker index for effective assessment of the disease and may provide in-depth information for better understanding the pathogenesis of gastric cancer.postprin

Proteomic approach to study the cytotoxicity of dioscin (saponin)

Dioscin, extracted from the root of Polygonatum zanlanscianense pamp, exhibits cytotoxicity towards human myeloblast leukemia HL-60 cells. Proteomic analysis revealed that the expression of mitochondrial associated proteins was substantially altered in HL-60 cells corresponding to the dioscin treatment, suggesting that mitochondria are the major cellular target of dioscin. Mitochondrial functional studies validated that mitochondrial apoptotic pathway was initiated by dioscin treatment. Changes in proteome other than mitochondrial related proteins implicate that other mechanisms were also involved in dioscin-induced apoptosis in HL-60 cells, including the activity impairment in protein synthesis, alterations of phosphatases in cell signaling, and deregulation of oxidative stress and cell proliferation. Current study of protein alterations in dioscin-treated HL-60 cells suggested that dioscin exerts cytotoxicity through multiple apoptosis-inducing pathways. © 2006 Wiley-VCH Verlag GmbH & Co. KGaA.postprin

Sample entropy analysis of EEG signals via artificial neural networks to model patients' consciousness level based on anesthesiologists experience.

Electroencephalogram (EEG) signals, as it can express the human brain's activities and reflect awareness, have been widely used in many research and medical equipment to build a noninvasive monitoring index to the depth of anesthesia (DOA). Bispectral (BIS) index monitor is one of the famous and important indicators for anesthesiologists primarily using EEG signals when assessing the DOA. In this study, an attempt is made to build a new indicator using EEG signals to provide a more valuable reference to the DOA for clinical researchers. The EEG signals are collected from patients under anesthetic surgery which are filtered using multivariate empirical mode decomposition (MEMD) method and analyzed using sample entropy (SampEn) analysis. The calculated signals from SampEn are utilized to train an artificial neural network (ANN) model through using expert assessment of consciousness level (EACL) which is assessed by experienced anesthesiologists as the target to train, validate, and test the ANN. The results that are achieved using the proposed system are compared to BIS index. The proposed system results show that it is not only having similar characteristic to BIS index but also more close to experienced anesthesiologists which illustrates the consciousness level and reflects the DOA successfully.This research is supported by the Center forDynamical Biomarkers and Translational Medicine, National Central University, Taiwan, which is sponsored by Ministry of Science and Technology (Grant no. MOST103-2911-I-008-001). Also, it is supported by National Chung-Shan Institute of Science & Technology in Taiwan (Grant nos. CSIST-095-V301 and CSIST-095-V302)

Endoscopic submucosal dissection vs laparoscopic colorectal resection for early colorectal epithelial neoplasia

published_or_final_versio

Proteomic analysis of a preneoplastic phenotype in ovarian surface epithelial cells derived from prophylactic oophorectomies

Objective. To study the pattern of protein expression associated with a predisposition to develop ovarian cancer. Methods. Prophylactic oophorectomy is used to prevent ovarian carcinoma in high-risk populations who have a strong family history of breast/ovarian cancer. In ovarian specimens of these women, the ovarian surface epithelium (OSE), which is tissue of origin of epithelial ovarian cancer, often shows altered morphology, growth patterns and differentiation features that are believed to be preneoplastic. This study has used a proteomic approach, based on two-dimensional gel electrophoresis and mass spectrometry, to compare the protein profiles of OSE from women with a history of familial ovarian cancer (FH-OSE), i.e., at least two first-degree relatives with such cancer and/or testing positive for BRCA1 mutations, to those without such history (NFH-OSE). Results. Of >1500 protein spots, there were 8 proteins whose levels were significantly altered in FH-OSE. Three were known ovarian tumor associated proteins, others were novel changes. A number of the alterations seen were accompanied with protein modifications and have not been previously reported. There was a predominance of sequences related to the stress response pathway. Differential expression of selected genes was confirmed by Western blotting and real-time reverse transcription polymerase chain reaction. Conclusions. Our findings define the OSE phenotype of women at a high risk of developing ovarian cancer. Protein alterations seen in these tissues may represent an early, irreversible, non-mutational step in ovarian epithelial neoplastic progression and may be potential early and sensitive markers for the evaluation of cancer risk. © 2005 Elsevier Inc. All rights reserved.postprin

The Embryotrophic Activity of Oviductal Cell-derived Complement C3b and iC3b, a Novel Function of Complement Protein in Reproduction

The oviduct-derived embryotrophic factor, ETF-3, enhances the development of trophectoderm and the hatching process of treated embryos. Monoclonal anti-ETF-3 antibody that abolishes the embryotrophic activity of ETF-3 recognized a 115-kDa protein from the conditioned medium of immortalized human oviductal cells. Mass spectrometry analysis showed that the protein was complement C3. Western blot analysis using an antibody against C3 confirmed the cross-reactivities between anti-C3 antibody with ETF-3 and anti-ETF-3 antibody with C3 and its derivatives, C3b and iC3b. Both derivatives, but not C3, were embryotrophic. iC3b was most efficient in enhancing the development of blastocysts with larger size and higher hatching rate, consistent with the previous reported embryotrophic activity of ETF-3. Embryos treated with iC3b contained iC3b immunoreactivity. The oviductal epithelium produced C3 as evidenced by the presence of C3 immunoreactivity and mRNA in the human oviduct and cultured oviductal cells. Cyclical changes in the expression of C3 immunoreactivity and mRNA were also found in the mouse oviduct with the highest expression at the estrus stage. Molecules involving in the conversion of C3b to iC3b and binding of iC3b were present in the human oviduct (factor I) and mouse preimplantation embryo (Crry and CR3), respectively. In conclusion, the present data showed that the oviduct produced C3/C3b, which was converted to iC3b to stimulate embryo development.postprin

Cefotaxime/sulbactam plus gentamicin as a potential carbapenem- and amikacin-sparing first-line combination for neonatal sepsis in high ESBL prevalence settings

BACKGROUND: Infection with ESBL-producing Enterobacteriaceae infection is ubiquitous in some neonatal ICUs and increasing levels of antibiotic resistance are a cause for urgent concern. Delineation of bacterial and viral sepsis can be challenging, often leading to patients receiving empirical antibiotics without or whilst waiting for a definitive causal diagnosis. Empirical therapy is often dependent on broad-spectrum ‘Watch’ antibiotics, contributing to further resistance. METHODS: ESBL-producing Enterobacteriaceae clinical isolates found to have caused neonatal sepsis and meningitis underwent a detailed in vitro screening including susceptibility testing, chequerboard combination analysis and hollow-fibre infection model dynamic analyses using combinations of cefotaxime, ampicillin and gentamicin in combination with β-lactamase inhibitors. RESULTS: Additivity or synergy was found for all antibiotic combinations against seven Escherichia coli and three Klebsiella pneumoniae clinical isolates. Cefotaxime or ampicillin plus sulbactam combined with gentamicin was able to consistently inhibit the growth of ESBL-producing isolates at typical neonatal doses, and the combination cleared the hollow-fibre infection model system of organisms resistant to each agent alone. The combination of cefotaxime/sulbactam and gentamicin was consistently bactericidal at clinically achievable concentrations (Cmax of 180, 60 and 20 mg/L for cefotaxime, sulbactam and gentamicin, respectively). CONCLUSIONS: The addition of sulbactam to cefotaxime or ampicillin to the typical first-line empirical therapy could obviate the need for carbapenems and amikacin in settings with high ESBL-infection prevalence