METTL3/YTHDC1-mediated upregulation of LINC00294 promotes hepatocellular carcinoma progression.

Hepatocellular carcinoma (HCC) is a highly prevalent malignancy and the third highest contributor to cancer-associated deaths globally. Research has increasingly demonstrated a strong correlation between long noncoding RNAs (lncRNAs) and the incidence and progression of HCC. Nonetheless, the exact mechanism whereby the function of lncRNAs in HCC has not been elucidated. This study explored the pathological role of LINC00294 in HCC, as well as the modulatory mechanism involved. Based on the "The Cancer Genome Atlas (TCGA)" database and validation in HCC cell lines and tissues, the expression of LINC00294 was discovered to be upregulated in HCC tissues and correlated with tumor grade and the prognosis of patients with HCC. Functionally, LINC00294 stimulated the proliferation of HCC cells as well as the Warburg effect (aerobic glycolysis) to enhance progression of tumor in vivo. Mechanistically, METTL3/YTHDC1-mediated N6-methyladenosine (m6A) modification underwent a significant enrichment within LINC00294 and was shown to enhance its RNA stability. Moreover, LINC00294 promoted the interaction between YTHDC1 and HK2 and GLUT1 mRNA. Overall, our study illustrates the m6A modification-mediated epigenetic mechanism of LINC00294 expression and regulatory role in HK2and GLUT1 mRNA expression and indicate LINC00294 as a potential biomarker panel for prognostic prediction and treatment in HCC.

Automatic snoring detection using a hybrid 1D-2D convolutional neural network.

Snoring, as a prevalent symptom, seriously interferes with life quality of patients with sleep disordered breathing only (simple snorers), patients with obstructive sleep apnea (OSA) and their bed partners. Researches have shown that snoring could be used for screening and diagnosis of OSA. Therefore, accurate detection of snoring sounds from sleep respiratory audio at night has been one of the most important parts. Considered that the snoring is somewhat dangerously overlooked around the world, an automatic and high-precision snoring detection algorithm is required. In this work, we designed a non-contact data acquire equipment to record nocturnal sleep respiratory audio of subjects in their private bedrooms, and proposed a hybrid convolutional neural network (CNN) model for the automatic snore detection. This model consists of a one-dimensional (1D) CNN processing the original signal and a two-dimensional (2D) CNN representing images mapped by the visibility graph method. In our experiment, our algorithm achieves an average classification accuracy of 89.3%, an average sensitivity of 89.7%, an average specificity of 88.5%, and an average AUC of 0.947, which surpasses some state-of-the-art models trained on our data. In conclusion, our results indicate that the proposed method in this study could be effective and significance for massive screening of OSA patients in daily life. And our work provides an alternative framework for time series analysis.

Establishment of sex-specific predictive models for critical illness in Chinese people with the Omicron variant.

Introduction: The Omicron variant has rapidly spread throughout the world compared to the Delta variant and poses a great threat to global healthcare systems due to its immune evasion and rapid spread. Sex has been identified as a factor significantly associated with COVID-19 mortality, but it remains unclear which clinical indicators could be identified as risk factors in each sex group and which sex-specific risk factors might shape the worse clinical outcome, especially for Omicrons. This study aimed to confirm the relationship between sex and the progression of the Omicron variant and to explore its sex-biased risk factors. Methods: We conducted a retrospective study including 1,132 hospitalized patients with the COVID-19 Omicron variant from 5 December 2022 to 25 January 2023 at Shanghai General Hospital, and the medical history data and clinical index data of the inpatients for possible sex differences were compared and analyzed. Then, a sex-specific Lasso regression was performed to select the variables significantly associated with critical illness, including intensive care unit admission, invasive mechanical ventilation, or death. A logistic regression was used to construct a sex-specific predictive model distinctively for the critical illness outcome using selected covariates. Results: Among the collected 115 clinical indicators, up to 72 showed significant sex differences, including the difference in merit and the proportion of people with abnormalities. More importantly, males had greater critical illness (28.4% vs. 19.9%) and a significantly higher intensive care unit occupancy (20.96% vs. 14.49%) and mortality (13.2% vs. 4.9%), and males over 80 showed worse outcomes than females. Predictive models (AUC: 0.861 for males and 0.898 for females) showed 12 risk factors for males and 10 for females. Through a comprehensive sex-stratified analysis of a large cohort of hospitalized Omicron-infected patients, we identified the specific risk factors for critical illness by developing prediction models. Discussion: Sex disparities and the identified risk factors should be considered, especially in the personalized prevention and treatment of the COVID-19 Omicron variant.

A Spiking Neural Network Based on Retinal Ganglion Cells for Automatic Burn Image Segmentation.

Burn is a common traumatic disease. After severe burn injury, the human body will increase catabolism, and burn wounds lead to a large amount of body fluid loss, with a high mortality rate. Therefore, in the early treatment for burn patients, it is essential to calculate the patient's water requirement based on the percentage of the burn wound area in the total body surface area (TBSA%). However, burn wounds are so complex that there is observer variability by the clinicians, making it challenging to locate the burn wounds accurately. Therefore, an objective, accurate location method of burn wounds is very necessary and meaningful. Convolutional neural networks (CNNs) provide feasible means for this requirement. However, although the CNNs continue to improve the accuracy in the semantic segmentation task, they are often limited by the computing resources of edge hardware. For this purpose, a lightweight burn wounds segmentation model is required. In our work, we constructed a burn image dataset and proposed a U-type spiking neural networks (SNNs) based on retinal ganglion cells (RGC) for segmenting burn and non-burn areas. Moreover, a module with cross-layer skip concatenation structure was introduced. Experimental results showed that the pixel accuracy of the proposed reached 92.89%, and our network parameter only needed 16.6 Mbytes. The results showed our model achieved remarkable accuracy while achieving edge hardware affinity.

Innate immune responses against the fungal pathogen Candida auris.

Candida auris is a multidrug-resistant human fungal pathogen responsible for nosocomial outbreaks worldwide. Although considerable progress has increased our understanding of the biological and clinical aspects of C. auris, its interaction with the host immune system is only now beginning to be investigated in-depth. Here, we compare the innate immune responses induced by C. auris BJCA001 and Candida albicans SC5314 in vitro and in vivo. Our results indicate that C. auris BJCA001 appears to be less immunoinflammatory than C. albicans SC5314, and this differential response correlates with structural features of the cell wall.

SGLT2 inhibitor-empagliflozin treatment ameliorates diabetic retinopathy manifestations and exerts protective effects associated with augmenting branched chain amino acids catabolism and transportation in db/db mice.

Empagliflozin (EMPA) is the first sodium-glucose co-transporter 2 inhibitor to significantly reduce cardiovascular and kidney complications in type 2 diabetes mellitus. Given this, we speculate that EMPA may have the potential to intervene in diabetic retinopathy (DR), which is another diabetes-specific microvascular complication. Db/db mice were treated with EMPA for different periods to observe the retinas and related mechanisms. EMPA effectively balanced body weight and blood glucose levels, mitigated ocular edema and microaneurysm in db/db mice. EMPA significantly inhibited oxidative stress, apoptosis and recovered tight junction in diabetic retinas. MS/MS analyses showed that EMPA suppressed aberrant branched-chain amino acid (BCAAs) accumulation in db/db retinas, which led to the inhibition of the mammalian target of rapamycin activation, downregulation of inflammation, and angiogenic factors, including TNF-ɑ, IL-6, VCAM-1, and VEGF induced by diabetes. Furthermore, branched-chain α-keto acids (BCKAs), which are catabolites of BCAAs, were increased in diabetic retinas and decreased with EMPA application. Moreover, branched-chain ketoacid dehydrogenase kinase (BCKDK) was enhanced, BCKDHA and BCKDHB were decreased in diabetic retinas. This could be reversed by EMPA treatment, thus promoting BCAAs catabolism to decrease BCAAs and BCKAs accumulation in diabetic retinas. The high levels of BCAAs in the plasma and enhanced L-type amino acid transporter 1 (LAT1) were responsible for the high levels of BCAAs in diabetic retinas, which could be inhibited by EMPA. Overall, EMPA could ameliorate DR manifestations. The normalization of BCAAs catabolism and intake may play a role in this process. This study supports EMPA as a protective drug against DR.

Follicular Helper T Cells Remodel the Immune Microenvironment of Pancreatic Cancer via Secreting CXCL13 and IL-21.

Immunosuppression is an important factor for the poor prognosis of pancreatic ductal adenocarcinoma (PDAC). Follicular helper T cells (Tfh cells) play an anti-tumor role in various malignant solid tumors and predict better patient prognosis. In the present study, we aimed to determine the immunosuppressive mechanism associated with Tfh cells and explore a new strategy to improve the tumor microenvironment of PDAC. Flow cytometry was used to detect the infiltration and proportion of Tfh cells in tumor tissues and peripheral blood from patients with PDAC. The spatial correlations of Tfh cells with related immune cells were evaluated using immunofluorescence. The function of Tfh cells was examined using in vitro and in vivo model systems. The high infiltration of Tfh cells predicted better prognosis in patients with PDAC. Tfh cells recruited CD8+ T cells and B cells by secreting C-X-C motif chemokine ligand 13 (CXCL13), and promoted the maturation of B cells into antibody-producing plasma cells by secreting interleukin 21 (IL-21), thereby promoting the formation of an immunoactive tumor microenvironment. The function of Tfh cells was inhibited by the programmed cell death 1 ligand 1 (PD-L1)/programmed cell death 1 (PD-1) signaling pathway in PDAC, which could be reversed using neoadjuvant chemotherapy. Treatment with recombinant CXCL13, IL-21 and Tfh cells alleviated tumor growth and enhanced the infiltration of CD8+ T cells and B cells, as well as B cell maturation in a PDAC mouse model. Our results revealed the important role of Tfh cells in mediating anti-tumor cellular immunity and humoral immunity in PDAC via secreting CXCL13 and IL-21 and determined a novel mechanism of immunosuppression in PDAC.

Evaluation of atherogenic lipoprotein-cholesterol to HDL cholesterol ratio as a prognostic test for ST-segment elevation myocardial infarction.

Background: The detectable component of triglyceride-rich lipoproteins (TGRLs), remnant lipoprotein cholesterol (RLP-c), has been proven being correlated with the progression of atherosclerosis and myocardial infarction. However, when taken as a risk predictor, the prognostic and diagnostic potential of RLP-c remains controversial in studies. In this study, we evaluated the hypothesis that atherogenic lipoprotein-cholesterol (AL-c), representing the sum of RLP-c and the sd-LDL-c, to the HDL-c ratio, could represent a better predictive indicator than RLP-c alone in ST-segment elevation myocardial infarction (STEMI). Methods: The 316 consecutive patients suffering from persistent chest discomfort admitted to the Shanghai General Hospital between January 2018 and June 2018 were enrolled. 149 STEMI patients (62% men, mean age 69.6 ± 13.3 years) were included as the study cohort. The AL-c/HDL-c ratio was calculated on admission in a cohort of electrocardiogram-confirmed STEMI patients and compared to other lipid profiles as a predictive indicator. Results: The AL-c/HDL-c ratio was significantly increased in STEMI patients compared with apparently healthy adults (0.93; IQR [0.71-1.18] vs 0.70; IQR [0.45-1.04]; p < 0.001). Gender dependency existed, and the male and female patients had median AL-c/HDL-c ratios of 1.01 and 0.79, respectively (p < 0.001). Compared to RLP-c, the AL-c/HDL-c ratio had a better prognostic value to predict STEMI risk in both sexes (AUC of 0.672 with a sensitivity of 0.794 in males and 0.613 with a sensitivity of 0.684 in females). Conclusions: The AL-c/HDL-c ratio could represent a convenient and sensitive biomarker for screening and predicting STEMI risk.

Single-Cell Sequencing-Enabled Hexokinase 2 Assay for Noninvasive Bladder Cancer Diagnosis and Screening by Detecting Rare Malignant Cells in Urine.

Bladder cancer (BC) is among the most common tumors with a high recurrence rate, necessitating noninvasive and sensitive diagnostic methods. Accurate detection of exfoliated tumor cells (ETCs) in urine is crucial for noninvasive BC diagnosis but suffers from limited sensitivity when ETCs are rare and confounded by reactive, regenerative, or reparative cells. Single-cell sequencing (SCS) enables accurate detection of ETCs by surveying oncogenic driver mutations or genome-wide copy number alternations. To overcome the low-throughput limitation of SCS, we report a SCS-validated cellular marker, hexokinase 2 (HK2), for high-throughput screening cells in urine and detecting ETCs engaging elevated glycolysis. In the SCS-based training set, a total of 385 cells from urine samples of eight urothelial carcinoma (UC) patients were sequenced to establish a HK2 threshold that achieved >90% specificity for ETC detection. This urine-based HK2 assay was tested with a blinded patient group (n = 384) including UC and benign genitourinary disorders as a validation cohort for prospectively evaluating diagnostic accuracy. The sensitivity, specificity, positive predictive value, and negative predictive value of the assay were 90, 88, 83, and 93%, respectively, which were superior to urinary cytology. For investigating the potential to be a screening test, the HK2 assay was tested with a group of healthy individuals (n = 846) and a 6-month follow-up. The specificity was 98.4% in this health group. Three participants were found to have >5 putative ETCs that were sequenced to exhibit recurrent copy number alternations characteristic of malignant cells, demonstrating early BC detection before current clinical methods.

Donor polymorphisms of Rap1A rs494453 contribute to a higher risk of hepatocellular carcinoma recurrence following liver transplantation.

Background: Hepatocellular carcinoma (HCC) recurrence appears commonly after liver transplantation (LT), and it severely affected the long-term survival of patients. Previous studies have proved that Rap1A is involved in hepatocarcinogenesis and metastasis, and demonstrated the significant association between Rap1A gene rs494453 polymorphism and HCC. However, the relationship between Rap1A rs494453 polymorphism and HCC recurrence after LT remained unclear. Methods: A total of 74 HCC patients who underwent LT from July 2005 to June 2015 was analyzed. The genotypes of both donors and recipients had been confirmed as Rap1A rs494453. The independent risk factors that associated with HCC recurrence were investigated with univariate and multivariate logistic regression analysis. The recurrence-free (RFS) and overall survival (OS) were calculated with Cox regression analysis. The Rap1A rs494453 genotype frequencies were determined using the Χ² test and the minor allele frequencies (MAFs) of Rap1A rs494453 genotypes were calculated by Hardy-Weinberg equilibrium. Results: We found that the donor Rap1A rs494453 polymorphism was profoundly associated with HCC recurrence after LT. Moreover, the Milan criteria, microvascular invasion and donor Rap1A rs494453 genotype were proved to be independent risk factors for HCC recurrence. Patients with donor AG/GG genotypes had a distinct lower RFS and OS than AA genotype. The TNM stage, Milan criteria, microvascular invasion, and donor Rap1A rs494453 genotype were independent factors for the RFS of LT patients. Conclusions: Donor Rap1A rs494453 is a potential predictive marker for HCC recurrence risk after LT.

Microstructure and Wear Properties of Micro Arc Oxidation Ceramic Coatings.

The interaction effect of micro arc oxidation (MAO) parameters on the microstructure and wear properties was investigated. The results showed that the electric current and oxidation time significantly influenced the thickness and grinding crack width of the ceramic coatings within the range of the selected parameters, and the interaction effect of the electrical parameters was not obvious. The surface morphology, cross-section morphology, and element distribution of the coatings were observed using scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). The results showed that ceramic coatings with γ-Al2O3 and α-Al2O3 formed, which enhanced the coating performance. After that, the microhardness and wear resistance were tested. Under the optimal process, the microhardness of a coating section was up to 1200 HV0.1, and the friction coefficient was just 0.3. When wear occurred, the volcanic microstructures experienced extrusion and deformation, and then peeled off under shear stress, which led to the formation of a grinding crack. The main failure modes of the micro arc oxidation coatings were abrasive wear and spalling failure.

Ubiquitin specific peptidase 5 promotes ovarian cancer cell proliferation through deubiquitinating HDAC2.

Globally, epithelial ovarian cancer (EOC) is the most common gynecological malignancy with poor prognosis. The expression and oncogenic roles of ubiquitin specific peptidase 5 (USP5) have been reported in several cancers except EOC. In the current study, USP5 amplification was highly prevalent in patients with EOC and associated with higher mRNA expression of USP5. USP5 amplification and overexpression was positively correlated with poor prognosis of patients of ovarian serous carcinomas. Disruption of USP5 profoundly repressed cell proliferation by inducing cell cycle G0/G1 phase arrest in ovarian cancer cells. Additionally, USP5 knockdown inhibited xenograft growth in nude mice. Knockdown of USP5 decreased histone deacetylase 2 (HDAC2) expression and increased p27 (an important cell cycle inhibitor) expression in vitro and in vivo. The promoting effects of USP5 overexpression on cell proliferation and cell cycle transition, as well as the inhibitory effects of USP5 overexpression on p27 expression were mediated by HDAC2. Moreover, USP5 interacted with HDAC2, and disruption of USP5 enhanced the ubiquitination of HDAC2. HDAC2 protein was positively correlated USP5 protein, and negatively correlated with p27 protein in ovarian serous carcinomas tissues. Collectively, our data suggest the oncogenic function of USP5 and the potential regulatory mechanisms in ovarian carcinogenesis.

Expanded CD14hiCD16- Immunosuppressive Monocytes Predict Disease Severity in Patients with Acute Pancreatitis.

Mild acute pancreatitis (AP) is a self-limiting disease, whereas severe AP has high mortality because of enhanced systemic inflammation and multiple organ failure. In experimental models of AP, infiltration of monocytes and activation of monocyte-derived macrophages largely determine the severity of the disease. Our previous studies have shown that CD11b+Ly-6Chi inflammatory monocytes were mobilized from bone marrow into peripheral blood and inflamed pancreas during the early stage of AP. However, the phenotype and characteristics of circulating monocytes in patients with AP are not well defined. Fifty patients with AP and nine age- and sex-matched healthy volunteers were enrolled in this study. Compared with those of healthy volunteers, the proportion of CD14hiCD16- monocytes and the level of myeloid-related cytokines/chemokines were increased in AP patients within 48 h after disease onset, especially in patients with a severe disease course. Moreover, the increased monocyte proportions were associated with decreased HLA-DR expression and a reduced T cell count. Notably, dynamic changes in circulating CD14hiCD16- monocytes and their HLA-DR expression, as well as in CD4+ T cells, were obviously different between moderate severe AP and severe AP. Last, area under the receiver operating characteristic analysis showed that the combination of CD14hiCD16- monocyte proportions with their HLA-DR level had higher accuracy for predicting the severity of AP. Taken together, the ratio of CD14hiCD16- monocytes and their HLA-DR level might assist in predicting the severity of disease in AP patients at admission and in monitoring patients' clinical status during recovery.

Decreased Susceptibility to Azithromycin Among Clinical Shigella Isolates from China.

The aim of this study was to detect the decreased susceptibility to azithromycin (DSA) and associated mechanisms in Shigella from China. Three hundred and ninety-two Shigella isolates, including 134 Shigella flexneri and 258 Shigella sonnei isolates, were examined for minimum inhibitory concentrations (MICs) and zone sizes to azithromycin by broth microdilution and disk diffusion methods, respectively. The MICs were compared with corresponding zone diameters to find whether there was uniformity between both tests. Twelve macrolide-resistant genes located on mobile elements were determined for the DSA isolates by PCR, and chromosomal efflux pump activity was analyzed using Phe-Arg-ß-naphthylamide inhibition test and quantitative real-time PCR. Shigella isolates displayed MICs of 0.125-512 µg/ml and zone sizes of 6-26 mm against azithromycin. There were 80 (20.4%) isolates to be DSA. No significant difference was found between the DSA rates of S. flexneri and S. sonnei isolates (p = 0.052). There was an intimate relativity between MICs and zone diameters (p < 0.001). Only the plasmid-borne mphA conferring high-level DSA was detected in 55.0% (44/80) DSA-Shigella isolates. This study highlighted the prevalence of DSA-Shigella and mphA in the region studied. Clinical laboratories and clinicians should pay attention to the elevated azithromycin MICs in Shigella spp.

[The relationship between high-sensitivity C-reactive protein and peripheral artery disease].

OBJECTIVE: To investigate the association between high-sensitivity C-reactive protein and peripheral arterial disease. METHODS: The study population comprised 643 subjects aged at least 40 years in whom both CRP and ankle-brachial index were measured. The survey included information on demographic characteristics, clinical examinations and ankle-brachial index (ABI). Ankle-brachial index (ABI) < 0.9 was diagnostic of PAD. RESULTS: 64 subjects (10%) were diagnosed as PAD. The prevalence of current smoking, hypertension, diabetes, low HDL cholesterol and history of cardiovascular disease in the participants with PAD were higher than without (P < 0.05). The prevalence of hypertension, diabetes, and history of cardiovascular disease was higher in subjects with high CRP (P < 0.05). In logistic regression analyses, the moderate CRP group and high CRP group had a two-fold higher OR compared with the low CRP group. The P-trend across CRP groups was statistically significant (P = 0.036). High log-transformed hs-CRP level was significantly related to PAD after adjustment for the cardiovascular risk factors mentioned above (P = 0.007). CONCLUSION: hs-CRP is related to PAD and high level hs-CRP is an independent risk factor for PAD in Chinese adults aged 40 years and more.

Process outgrowth in oligodendrocytes is mediated by CNP, a novel microtubule assembly myelin protein.

Oligodendrocytes (OLs) extend arborized processes that are supported by microtubules (MTs) and microfilaments. Little is known about proteins that modulate and interact with the cytoskeleton during myelination. Several lines of evidence suggest a role for 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNP) in mediating process formation in OLs. In this study, we report that tubulin is a major CNP-interacting protein. In vitro, CNP binds preferentially to tubulin heterodimers compared with MTs and induces MT assembly by copolymerizing with tubulin. CNP overexpression induces dramatic morphology changes in both glial and nonglial cells, resulting in MT and F-actin reorganization and formation of branched processes. These morphological effects are attributed to CNP MT assembly activity; branched process formation is either substantially reduced or abolished with the expression of loss-of-function mutants. Accordingly, cultured OLs from CNP-deficient mice extend smaller outgrowths with less arborized processes. We propose that CNP is an important component of the cytoskeletal machinery that directs process outgrowth in OLs.

Human serum proteins preseparated by electrophoresis or chromatography followed by tandem mass spectrometry.

Electrophoretic and chromatographic sample preparations were compared and together detected the presence of some 600 types of protein products in human serum. Proteins from crude serum preseparated by ionic electrophoresis, chromatography, or a combination of both were analyzed. Proteins were digested with trypsin or chymotrypsin. Naturally occurring peptides were also collected by reversed-phase chromatography. The resulting peptides were identified by tandem mass spectrometry. The peptides were either desorbed by a laser from a metal chip into a quadrupole-time-of-flight mass spectrometer or ionized as an electro-spray from reversed-phase chromatography via a metal needle under voltage into an ion-trap mass spectrometer. All of the commonly known proteins associated with serum were detected, and the two mass spectrometers agreed on the identity of abundant serum proteins. Preseparation of serum proteins prior to digestion markedly enhanced the capacity to detect un-common proteins from blood. Electrophoretic- and chromatography-based experiments were found to be complementary. Many novel cellular proteins not previously associated with serum were recorded.

Mining biomarkers in human sera using proteomic tools.

One of the major difficulties in mining low abundance biomarkers from serum or plasma is due to the fact that a small number of proteins such as albumin, alpha2-macroglobulin, transferrin, and immunoglobulins, may represent as much as 80% of the total serum protein. The large quantity of these proteins makes it difficult to identify low abundance proteins in serum using traditional 2-dimensional electrophoresis. We recently used a combination of multidimensional liquid chromatography and gel electrophoresis coupled to matrix-assisted laser desorption/ionization-quadrupole-time of flight and Ion Trap liquid chromatography-tandem mass spectrometry to identify protein markers in sera of Alzheimer's disease (AD), insulin resistance/type-2 diabetes (IR/D2), and congestive heart failure (CHF) patients. We identified 8 proteins that exhibit higher levels in control sera and 36 proteins that exhibit higher levels in disease sera. For example, haptoglobin and hemoglobin are elevated in sera of AD, IR/D2, and CHF patients. The levels of several other proteins including fibrinogen and its fragments, alpha 2-macroglobulin, transthyretin, pro-platelet basic protein, protease inhibitors clade A and C, as well as proteins involved in the classical complement pathway such as complement C3, C4, and C1 inhibitor, were found to differ between IR/D2 and control sera. The sera levels of proteins, such as the 10 kDa subunit of vitronectin, alpha 1-acid glycoprotein, apolipoprotein B100, fragment of factor H, and histidine-rich glycoprotein were observed to be different between AD and controls. The differences observed in these biomarker candidates were confirmed by Western blot and the enzyme-linked immunosorbent assay. The biological meaning of the proteomic changes in the disease states and the potential use of these changes as diagnostic tools or for therapeutic intervention will be discussed.

Processing of serum proteins underlies the mass spectral fingerprinting of myocardial infarction.

The MALDI-TOF spectra of peptides from the sera of normal and myocardial infarction patients produced patterns that provided an accurate diagnostic of MI. In myocardial infarction, the spectral pattern originated from the cleavage of complement C3 alpha chain to release the C3f peptide and cleavage of fibrinogen to release peptide A. The fibrinogen peptide A and complement C3f peptide were in turn progressively truncated by aminopeptidases to produce two families of fragments that formed the characteristic spectral pattern of MI. Time course and inhibitor studies demonstrated that the peptide patterns in the serum reflect the balance of disease-specific-protease and aminopeptidase activity ex vivo.

Identification of differentially expressed proteins in human glioblastoma cell lines and tumors.

An in-frame deletion of 801 bp in exons 2-7 (type III mutation) of the epidermal growth factor receptor (EGFR) is detected at high incidence in primary glioblastoma tumors. A proteomic approach was used to generate differential protein expression maps of fetal human astrocytes (FHA), human glioblastoma cell lines U87MG and U87MG expressing type III EGFR deletion (U87MGdeltaEGFR) that confers high malignancy to tumor cells. Two-dimensional gel electrophoresis followed by in-gel digestion of separated spots and protein identification by LC-MS-MS and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) identified 23 proteins expressed at higher levels or exclusively in FHA and 29 proteins expressed at higher levels or exclusively in U87MG cells. Three proteins, ubiquitin, cystatin B, and tissue transglutaminase (TTG), were upregulated in U87MGdeltaEGFR relative to U87MG. Four proteins highly expressed by U87MG cells, Hsp27, major vault protein, TTG, and cystatin B, were analyzed by Western blot, ELISA, or RT-PCR in cell extracts and in tissue samples of glioblastoma multiforme (GBM; grade IV), low-grade astrocytomas (grades I and II), and nonmalignant brain lesions. All four proteins were highly expressed in GBM tissues compared to nonmalignant brain. These proteins may be used as diagnostic or functional (e.g., multiple drug resistance, invasiveness) markers for glioblastoma tumors.