Clinical tumour markers in lung cancer

Plasma SNORD42B and SNORD111 as potential biomarkers for early diagnosis of non‐small cell lung cancer

Background

Non‐small‐cell lung cancer (NSCLC) still occupied the leading reason of cancer death due to lack of availability of early detection. This study aimed to identify the effective biomarkers for the early‐stage NSCLC diagnostics based on plasma snoRNAs.

Materials and Methods

The differential snoRNAs between lung cancer patients and healthy donors were analyzed using the SNORic and TCGA databases. SNORD42B and SNORD111 were screened out and further verified in 48 FFPE NSCLC and adjacent normal tissues, as well as in plasma from 165 NSCLC patients and 118 health donors using qRT‐PCR. Next, their diagnostic efficiency, as well as combined with carcinoembryonic antigen (CEA), was obtained by the analysis of receiver operating characteristic (ROC).

Results

We first screened out 47 top differential snoRNAs, among which the top 10 upregulated snoRNAs in LUAD were U44, U75, U78, U77, SNORD72, SNORD13, SNORD12B, SCARNA5, U80, SNORD41, and in LUSC were U44, U75, U78, SNORD41, SNORD111, SNORA56, U17a, SNORD35A, SNORD32A, SNORA71D. SNORD42B and SNORD111 was significantly increased not only in tumor tissues but also in plasma from NSCLC and early‐stage NSCLC patients. They were capable to act as promising biomarkers for NSCLC and early‐stage NSCLC diagnosis. Moreover, CEA diagnostic efficiency for early‐stage NSCLC was significantly improved when combined with these two plasma snoRNAs.

Conclusion

SNORD42B and SNORD111 could act as the potential and non‐invasive diagnostic biomarkers for NSCLC and early‐stage NSCLC.

An auto-antibody identified from phenotypic directed screening platform shows host immunity against EV-A71 infection

Background

Enterovirus A71 (EV-A71) is a neurotropic virus which may cause severe neural complications, especially in infants and children. The clinical manifestations include hand-foot-and-mouth disease, herpangina, brainstem encephalitis, pulmonary edema, and other severe neurological diseases. Although there are some vaccines approved, the post-marketing surveillance is still unavailable. In addition, there is no antiviral drugs against EV-A71 available.

Methods

In this study, we identified a novel antibody that could inhibit viral growth through a human single chain variable fragment (scFv) library expressed in mammalian cells and panned by infection with lethal dose of EV-A71.

Results

We identified that the host protein α-enolase (ENO1) is the target of this scFv, and anti-ENO1 antibody was found to be more in mild cases than severe EV-A71 cases. Furthermore, we examined the antiviral activity in a mouse model. We found that the treatment of the identified 07-human IgG₁ antibody increased the survival rate after virus challenge, and significantly decreased the viral RNA and the level of neural pathology in brain tissue.

Conclusions

Collectively, through a promising intracellular scFv library expression and screening system, we found a potential scFv/antibody which targets host protein ENO1 and can interfere with the infection of EV-A71. The results indicate that the usage and application of this antibody may offer a potential treatment against EV-A71 infection.

Plasma SNORD83A as a potential biomarker for early diagnosis of non-small-cell lung cancer

Aim: This study aimed to access the efficacy of plasma small nucleolar RNAs in early diagnosis of non-small-cell lung cancer (NSCLC). Methods: SNORD83A was selected based on databases and further verified in 48 paired formalin-fixed, paraffin-embedded tissues, as well as in plasma from 150 NSCLC patients and 150 healthy donors. The diagnostic efficiency of plasma SNORD83A, as well as in combination with carcinoembryonic antigen, was determined by receiver operating characteristic analysis. Results: SNORD83A was significantly increased not only in tissues but also in plasma from NSCLC patients compared with those from healthy donors. Plasma SNORD83A was able to act as a diagnostic biomarker for NSCLC. The diagnostic efficiency of carcinoembryonic antigen was also significantly elevated for early-stage NSCLC when combined with SNORD83A. Conclusion: SNORD83A can serve as a diagnostic biomarker for NSCLC.

Functional Micro-/Nanomaterials for Multiplexed Biodetection

When analyzing biological phenomena and processes, multiplexed biodetection has many advantages over single-factor biodetection and is highly relevant to both human health issues and advancements in the life sciences. However, many key problems with current multiplexed biodetection strategies remain unresolved. Herein, the main issues are analyzed and summarized: 1) generating sufficient signal to label targets, 2) improving the signal-to-noise ratio to ensure total detection sensitivity, and 3) simplifying the detection process to reduce the time and labor costs of multiple target detection. Then, available solutions made possible by designing and controlling the properties of micro- and nanomaterials are introduced. The aim is to emphasize the role that micro-/nanomaterials can play in the improvement of multiplexed biodetection strategies. Through analyzing existing problems, introducing state-of-the-art developments regarding relevant materials, and discussing future directions of the field, it is hopeful to help promote necessary developments in multiplexed biodetection and associated scientific research.

CircRNA_102179 promotes the proliferation, migration and invasion in non-small cell lung cancer cells by regulating miR-330-5p/HMGB3 axis

Non-small cell lung cancer (NSCLC) accounting for 85 % of all lung cancer was one of the main causes of death worldwide. In this study, we investigated the role of circRNA_102179 in NSCLC development. The levels of circRNA_102179 in NSCLC tissues and cell lines were determined by quantitative real-time PCR assay (qRT-PCR). CCK8 and colony formation assays were applied to explore the effect of circRNA_102179 on the growth of NSCLC cells in vitro. Transwell assay was utilized to analyze the impact of circRNA_102179 on the migration and invasion of NSCLC cells. Target prediction and luciferase reporter assay were used to identify the interacting miRNA of circRNA_102179. The interaction among circRNA_102179/ miR-330-5p/HMGB3 was further validated by colony formation and Transwell invasion assays. Finally, the mouse xenograft NSCLC model was used to explore the role of circRNA_102179 in the tumor growth of NSCLC cells in vivo. CircRNA_102179 was overexpressed in NSCLC tissues and cells compared with normal lung tissues and human bronchial epithelial cells (HBEs). The down-regulation of circRNA_102179 markedly reduced the proliferation, migration, and invasion of NSCLC cells. Moreover, down-expression of circRNA_102179 significantly increased the level of miR-330-5p/HMGB3 in NSCLC cells. Further functional experiments indicated that over-expression of miR-330-5p reversed the inhibitory effect of circRNA_102179 on NSCLC cells growth, migration, and invasion. Our results reveal that circRNA_102179 facilitates the proliferation, migration, and invasion of NSCLC cell via modulating miR-330-5p/ HMGB3 axis in NSCLC cells.

Effects of α-enolase Gene Silencing on Reproductive-related Hormone Receptor Expression and Steroid Hormone Synthesis of Primary Granulosa Cells from Goose F1 Follicles

Introduction

Enolases are enzymes in the glycolytic pathway, which catalyse the reversible conversion of D-2-phosphoglycerate into phosphoenol pyruvate in the second half of the pathway. In this research, the effects of α-enolase (ENO1) on steroid reproductive-related hormone receptor expression and on hormone synthesis of primary granulosa cells from goose F1 follicles were studied.

Material and Methods

Primary granulosa cells from the F1 follicles of eight healthy 8-month-old Zi geese were separated and cultured. An ENO1 interference expression vector was designed, constructed and transfected into primary cultured granulosa cells. The mRNA expression levels of follicle-stimulating hormone receptor (FSHR), luteinising hormone receptor (LHR), oestrogen receptor α (ER α), oestrogen receptor β (ER β), growth hormone receptor (GHR) and insulin-like growth factor binding protein-1 (IGFBP-1) in the cells were evaluated as were the secretion levels of oestradiol, activin, progesterone, testosterone, inhibin and follistatin in cell supernatant.

Results

α-enolase gene silencing reduced the expression of FSHR, LHR, ERα, ERβ, GHR, and IGFBP-1 mRNA, potentiated the secretion of oestrogen, progesterone, testosterone, and follistatin of granulosa cells, and hampered the production of activin and inhibin.

Conclusion

ENO1 can regulate the reactivity of granulosa cells to reproductive hormones and regulate cell growth and development by adjusting their hormone secretion and reproductive hormone receptor expression. The study provided a better understanding of the functional action of ENO1 in the processes of goose ovary development and egg laying.

Correction of serum NSE reference intervals includes the unidentified hemolysis sample: 1-year data analysis from healthcare individuals

BACKGROUND

Reference intervals (RIs) are important for interpretation of laboratory results. Neuron-specific enolase (NSE) can be utilized to aid the diagnosis of various tumors. However, while red blood cells contain NSE αγ-isozymes, unrecognized slight hemolysis will result in increasing of NSE levels in serum. The aim of this study was to correct the NSE RIs from healthcare individuals results which may have unidentified microhemolysis.

METHODS

A total of 15 047 healthy individuals undergoing regular health care were recruited to redefine the NSE reference interval according to the CA28-A3 document. Volunteers with NSE level between 16.3 ng/mL and the upper limit of new RIs were performed venipuncture for NSE retest. Simultaneously, serum free hemoglobin (fHb) was performed with o-tolidine test.

RESULTS

Reestablishment of NSE RIs is 0-18.9 ng/mL, which is wider than 0-16.3 ng/mL provided by the manufacturer. Seventy-four volunteers with the NSE level between 16.3 and 18.9 ng/mL were performed venipuncture for NSE retest. The ratio of NSE level drop to normal is 85.1% (63/74) in the subsequent results; there are significant differences between the median NSE of two groups (18.15 vs 14.15 ng/mL). Subsequently, the fHb concentration of 22 healthy individuals from 74 individuals was measured; there are significant differences between the median fHb of two groups (58 vs 30 mg/L).

CONCLUSIONS

Some specimens with slightly elevated NSE may be attributed to the unrecognized slight hemolysis. The correction RIs may be expected to decrease the abnormal NSE results.

Serum CA50 levels in patients with cancers and other diseases

Carbohydrate antigen 50 (CA50) is initially reported as a cancer-specific antigen expressed on the surface of human colorectal Colo-205 cancer cells. Subsequently, increased serum CA50 levels are observed in patients not only with colorectal cancers but also other types of cancers. Eventually, serum CA50 is measured clinically as a cancer biomarker. However, serum CA50 level does not always increase in cancer patients but does increase in patients suffering from nonneoplasm diseases, which indicates that serum CA50 is not produced by cancer cells exclusively. Therefore, the serum CA50 levels in patients suffering different types of diseases should be systematically compared in order to comprehend the molecular nature of serum CA50 as a biomarker. In our current study, we measured and analyzed serum CA50 levels from 2113 patients with 14 clinically defined diseases with at least 30 independent tests for each disease in addition to 13,997 serum samples from individuals who attend their annual physical examination as healthy controls. Based on the mean, median, and -Log₁₀p values, we found that patients suffering from pancreatic cancer, cirrhosis, pancreatitis, lung cancer, type 2 diabetes mellitus, and colon cancer had highest levels of serum CA50 while patients suffering from coronary heart disease, gastric cancer, and rectum cancer showed comparable serum CA50 levels to that of healthy controls. Moreover, patients with osteoporosis, anemia, or gastritis had lower serum CA50 levels than that of healthy controls. Furthermore, healthy individuals older than 65 years old had increased serum CA50 levels compared with that of healthy controls. Taken together, these data suggest that serum CA50 is likely to be a system malfunction biomarker, and the serum CA50 levels could be used as diagnostic biomarkers not only for cancers but also for other nonneoplasm diseases.

Gamma-enolase predicts lung damage in severe acute pancreatitis-induced acute lung injury

Severe acute pancreatitis (SAP) associated acute lung injury (ALI) accounts for about 70% mortality of SAP patients. However, there are no precise biomarkers for the disease currently. Herein, we evaluated the potential of gamma-enolase (ENO2), against its universal isoform alpha-enolase (ENO1), as a marker of SAP-ALI in a rat model. Firstly, 16 male Sprague-Dawley rats were randomly divided into two groups, Sham (n = 8) and SAP-ALI (n = 8), for pancreatitis induction. Ultra-structure examination by electron microscopy and HE staining were used for lung injury assessment. Lung tissue expressions of alpha-enolase and gamma-enolase were evaluated by qRT-PCR and immunohistochemistry. In a prospective validation experiment, 28 rats were used: sham (n = 8), SAP-ALI at 3 h (3 h, n = 10), and SAP-ALI at 24 h (24 h, n = 10). Lung tissue damage, tissue expression and circulating alpha-enolase and gamma-enolase levels were evaluated. Elevated serum levels of α-amylase and TNF-α were observed in SAP rats but not in sham-operated rats. Histological examination of pancreatic and lung tissues indicated marked damage in SAP rats. While alpha-enolase was universally expressed, gamma-enolase was expressed only in damaged lung tissues. Gamma-enolase was detected in lung tissues, BALF, and serum as early as 3 h post-surgery when physical pathological damage was not apparent. Unlike alpha-enolase, secreted and/or circulating gamma-enolase level progressively increased, especially in serum, as lung damage progressed. Thus, gamma-enolase may signal and correlate lung tissue damage well before obvious physical pathological tissue damage and might be a candidate diagnostic and/or prognostic marker.

Preoperative CEA, NSE, SCC, TPA and CYFRA 21.1 Serum Levels as Prognostic Indicators in Resected Non-Small Cell Lung Cancer

In 62 patients affected by resectable non-small cell lung cancer (NSCLC) submitted to radical surgery we evaluated the prognostic significance of CEA, NSE, SCC, TPA and CYFRA 21.1 serum levels at diagnosis, as well as the predictive ability of these tumor markers with respect to histological type and pathological stage. The group was composed of 56 male and 6 female patients; the median age was 62 years (range 29–73 years). Thirty-four patients had a histological diagnosis of adenocarcinoma and 28 of squamous cell carcinoma; with regard to pathological stage, 32 patients had stage I, 4 patients stage II and 23 patients stage IIIA disease. A good predictive ability with respect to histological type was obtained with SCC serum levels; as for pathological stage, TPA and CYFRA 21.1 were found to have moderate predictive ability. In this series of patients, at a median follow-up of 55 months after surgery, we found that both TPA and CYFRA 21.1 serum levels at diagnosis were reliable predictors of overall survival, high values of these markers being associated with a worse prognosis.

Arthritic role of Porphyromonas gingivalis in collagen-induced arthritis mice

Epidemiological studies show an association between rheumatoid arthritis (RA) and periodontal disease. Porphyromonas gingivalis (P.gingivalis) is a well-known pathogen in periodontitis. This study investigated the pathogenic effects of P.gingivalis on autoimmune arthritis in vivo. Collagen-induced arthritis (CIA) mice were intraperitoneally injected with W83 and 2561 strains of P.gingivalis. Infection with P.gingivalis exacerbated arthritis score in CIA mice. Synovial inflammation and bone destruction in CIA mice infected with P.gingivalis were more severe than in uninfected CIA mice. Both W83 and 2561 strains were more pro-arthritic after arthritis symptom was fully activated. Interestingly, only W83 strain was arthritogenic before autoimmune reaction initiated. Citrullination was detected in synovial tissue of CIA mice and CIA mice inoculated with P.gingivalis, but not in normal control mice. The citrullinated area was greater in P.gingivalis-infected CIA mice than in non-infected CIA mice. This study showed that P.gingivalis exacerbated disease in a mouse model of autoimmune arthritis and increased the expression of citrullinated antigens in the synovium. The arthritogenic effects of P.gingivalis were at least in part, dependent upon the bacterial strain with or without fimbriae expression, route and time of infection. P.gingivalis-mediated citrullination may explain the possible link between periodontal disease and RA.

Identification of α-enolase as a prognostic and diagnostic precancer biomarker in oral submucous fibrosis

AIMS

Diagnostic ambiguities regarding the malignant potentiality of oral submucous fibrosis (OSF), an oral precancerous condition having dysplastic and non-dysplastic isoforms are the major failure for early intervention of oral squamous cell carcinoma (OSCC) patients. Our goal is to identify proteomic signatures from biopsies that can be used as precancer diagnostic marker for patient suffering from OSF.

METHODS

The high throughput techniques adopting de novo peptide sequencing (1D SDS-PAGE coupled nanoLC MALDI tandem mass spectrometry (MS/MS)-based peptide mass fingerprint), immunohistochemistry (IHC), Western blot (WB) and real-time PCR (RT-PCR) analysis are considered for such biomarker identification and multilevel validations.

RESULTS

Alpha-enolase is identified as an overexpressed protein in biopsies of oral submucous fibrosis with dysplasia (OSFWD) compared with oral submucous fibrosis without dysplasia (OSFWT) and normal oral mucosa (NOM). Total proteome analysis of an overexpressed protein band around 47 kDa of OSFWD identifies 334 peptides corresponding to 61 human proteins. Among them α-enolase is identified as a prime protein with highest number of peptides (44 out of 334 peptides) and sequence coverage (66.4%). Furthermore, RT-PCR, WB and IHC analysis also show mRNA and tissue level upregulation of α-enolase in OSFWD validating α-enolase as precancer marker.

CONCLUSIONS

This study for the first time identifies and validates α-enolase as a novel biomarker for early diagnosis of malignant potentiality of OSF. Hence, the identified protein marker, α-enolase can help in early therapeutic intervention of OSF patients leading to the reduction of patient's pain, treatment cost and enhancement of patient's quality of life.

Neuron-Specific Enolase Predicts Poor Outcome After Cardiac Arrest and Targeted Temperature Management: A Multicenter Study on 1,053 Patients

OBJECTIVE

Outcome prediction after cardiac arrest is important to decide on continuation or withdrawal of intensive care. Neuron-specific enolase is an easily available, observer-independent prognostic biomarker. Recent studies have yielded conflicting results on its prognostic value after targeted temperature management.

DESIGN, SETTING, AND PATIENTS

We analyzed neuron-specific enolase serum concentrations 3 days after nontraumatic in-hospital cardiac arrest and out-of-hospital cardiac arrest and outcome of patients from five hospitals in Germany, Austria, and Italy. Patients were treated at 33°C for 24 hours. Cerebral Performance Category was evaluated upon ICU discharge. We performed case reviews of good outcome patients with neuron-specific enolase greater than 90 μg/L and poor outcome patients with neuron-specific enolase less than or equal to 17 μg/L (upper limit of normal).

MEASUREMENTS AND MAIN RESULTS

A neuron-specific enolase serum concentration greater than 90 μg/L predicted Cerebral Performance Category 4-5 with a positive predictive value of 99%, false positive rate of 0.5%, and a sensitivity of 48%. All three patients with neuron-specific enolase greater than 90 μg/L and Cerebral Performance Category 1-2 had confounders for neuron-specific enolase elevation. An neuron-specific enolase serum concentration less than or equal to 17 μg/L excluded Cerebral Performance Category 4-5 with a negative predictive value of 92%. The majority of 14 patients with neuron-specific enolase less than or equal to 17 μg/L who died had a cause of death other than hypoxic-ischemic encephalopathy. Specificity and sensitivity for prediction of poor outcome were independent of age, sex, and initial rhythm but higher for out-of-hospital cardiac arrest than for in-hospital cardiac arrest patients.

CONCLUSION

High neuron-specific enolase serum concentrations reliably predicted poor outcome at ICU discharge. Prediction accuracy differed and was better for out-of-hospital cardiac arrest than for in-hospital cardiac arrest patients. Our "in-the-field" data indicate 90 μg/L as a threshold associated with almost no false positives at acceptable sensitivity. Confounders of neuron-specific enolase elevation should be actively considered: neuron-specific enolase-producing tumors, acute brain diseases, and hemolysis. We strongly recommend routine hemolysis quantification. Neuron-specific enolase serum concentrations less than or equal to 17 μg/L argue against hypoxic-ischemic encephalopathy incompatible with reawakening.

Non-Coding RNAs in Lung Cancer: Contribution of Bioinformatics Analysis to the Development of Non-Invasive Diagnostic Tools

Lung cancer is currently the leading cause of cancer related mortality due to late diagnosis and limited treatment intervention. Non-coding RNAs are not translated into proteins and have emerged as fundamental regulators of gene expression. Recent studies reported that microRNAs and long non-coding RNAs are involved in lung cancer development and progression. Moreover, they appear as new promising non-invasive biomarkers for early lung cancer diagnosis. Here, we highlight their potential as biomarker in lung cancer and present how bioinformatics can contribute to the development of non-invasive diagnostic tools. For this, we discuss several bioinformatics algorithms and software tools for a comprehensive understanding and functional characterization of microRNAs and long non-coding RNAs.

Clinically Meaningful Use of Blood Tumor Markers in Oncology

Before the introduction of modern imaging techniques and the recent developments in molecular diagnosis, tumor markers (TMs) were among the few available diagnostic tools for the management of cancer patients. Easily obtained from serum or plasma samples, TMs are minimally invasive and convenient, and the associated costs are low. Single TMs were traditionally used but these have come under scrutiny due to their low sensitivity and specificity when used, for example, in a screening setting. However, recent research has shown superior performance using a combination of multiple TMs as a panel for assessment, or as part of validated algorithms that also incorporate other clinical factors. In addition, newer TMs have been discovered that have an increased sensitivity and specificity profile for defined malignancies. The aim of this review is to provide a concise overview of the appropriate uses of both traditional and newer TMs and their roles in diagnosis, prognosis, and the monitoring of patients in current clinical practice. We also look at the future direction of TMs and their integration with other diagnostic modalities and other emerging serum based biomarkers, such as circulating nucleic acids, to ultimately advance diagnostic performance and improve patient management.

A potential role for VEGF in the diagnostic approach of pleural effusions

BACKGROUND

Vascular endothelial growth factor (VEGF) may play a role in pleural fluid formation, as it represents a potent inducer of capillary permeability. We aimed to investigate the diagnostic utility of VEGF levels in pleural fluid and serum in patients with pleural effusions with initially negative diagnostic work up.

METHODS

Seventy-one patients with exudative lymphocytic pleural effusions undiagnosed after initial diagnostic work up were enrolled in this prospective study and their clinical course was followed up to 24 months. VEGF levels were measured in serum and pleural fluid by using immunoenzymometric assay.

RESULTS

During the follow up period, in 43 patients the pleural effusion was eventually attributed to malignancy while in the rest 28 patients it was due to non-malignant causes (benign and unknown origin). Patients with malignancy had significantly higher VEGF levels in pleural fluid compared to patients with non-malignant effusions (1,506 vs. 588 pg/dL, P=0.0001), while no statistically significant difference was found in the VEGF serum levels between the two groups.

CONCLUSIONS

Pleural VEGF levels may be helpful in identifying malignant pleural effusion (MPE) in patients with negative diagnostic work up at the initial assessment and help in selecting patients for more invasive procedures.

Mediastinal lymph node metastasis of renal cell carcinoma: A case report

Renal cell carcinoma (RCC) may metastasize to mediastinal lymph nodes without any abdominal lymph node involvement. The present study describes an autopsy-proven case of RCC presenting with a large mediastinal mass; the case had been previously misdiagnosed as small cell lung carcinoma due to imaging analysis results, an elevated serum level of neuron-specific enolase and the presence of small atypical cells with a high nuclear/cytoplasmic ratio. Despite RCC occurrence being rare, it should be considered in the differential diagnosis, particularly when a mass located in the kidneys presents with metastases to the mediastinal lymph nodes, even if there is no involvement of the abdominal lymph nodes and the primary lesion is of a small size.

A mass spectrometric insight into the origins of benign gynecological disorders

Applications of mass spectrometry (MS) are rapidly expanding and encompass molecular and cellular biology. MS aids in the analysis of in vivo global molecular alterations, identifying potential biomarkers which may improve diagnosis and treatment of various pathologies. MS has added new dimensionality to medical research. Pioneering gynecologists now study molecular mechanisms underlying female reproductive pathology with MS-based tools. Although benign gynecologic disorders including endometriosis, adenomyosis, leiomyoma, and polycystic ovarian syndrome (PCOS) carry low mortality rates, they cause significant physical, mental, and social detriments. Additionally, some benign disorders are unfortunately associated with malignancies. MS-based technology can detect malignant changes in formerly benign proteomes and metabolomes with distinct advantages of speed, sensitivity, and specificity. We present the use of MS in proteomics and metabolomics, and summarize the current understanding of the molecular pathways concerning female reproductive anatomy. Highlight discoveries of novel protein and metabolite biomarkers via MS-based technology, we underscore the clinical application of these techniques in the diagnosis and management of benign gynecological disorders. © 2015 Wiley Periodicals, Inc. Mass Spec Rev 36:450-470, 2017.

Proteomics in gastric cancer research: Benefits and challenges

Among various cancers, gastric cancer (GC) exhibits relatively high morbidity and mortality rate worldwide. The lack of effective methods in early detection and diagnosis, and immediate therapies makes treating such disease a challenge for both clinicians and oncologists. Proteomics has emerged as a promising technology platform for rationally identifying biomarkers and novel therapeutic targets for GC, as well as discovering underlying mechanisms of carcinogenesis. Its application has greatly benefited mechanistic studies of this disease. This review will demonstrate the applications of proteomic technology in GC research. The advantages and shortcomings of this technology, as reflected by current studies, will also be discussed to improve and expand its application in the field of cancer research.

Regulation of cellular iron metabolism and its implications in lung cancer progression

Iron is essential for life and is involved in numerous metabolic processes including cell growth and proliferation. However, excess iron in the body raises the risk of developing cancer due to its capacity to engage in redox cycling and free radical production. Therefore, iron can contribute to both carcinogenesis and tumor growth. Both epidemiologic and laboratory studies have demonstrated that the effects of iron overload are associated with the tumorigenesis of lung cancer and growth of lung cancer cells. In particular, the discovery of hepcidin and several iron transporters in the past decade may warrant reconsideration of the role of iron in carcinogenesis and tumor cell proliferation in lung cancer. Pathways of iron uptake, storage, efflux, and regulation are all disturbed in cancer, suggesting that reprogramming of iron metabolism is a critical aspect of tumor cell survival. Although these pathways in lung cancer have been identified and extensively studied, many issues on the metabolic processes of iron in lung cancer cells have not been addressed. Targeting metabolic pathways of iron may provide new tools for lung cancer prognosis and therapy.

A microarray method for identifying tumor antigens by screening a tumor cDNA expression library against cancer sera

The immune system responds to tumor cells. The challenge has been how to effectively use these responses to treat or protect against cancer. Toward the goal of developing a cancer vaccine, we are pursuing methodologies for the discovery and testing of useful antigens. We present an array-based approach for discovering these B cell antigens by directly screening for specific host-sera reactivity to lysates from tumor-derived cDNA expression libraries. Several cancer-specific antigens were identified, and these are currently being validated as potential candidates.

Individualized correction of neuron-specific enolase (NSE) measurement in hemolyzed serum samples

BACKGROUND

Accuracy of serum neuron-specific enolase (NSE) measurement is paramount, particularly in the context of neurological outcome prognostication. However, NSE measurements are compromised by even slight hemolysis, as it is abundant in red blood cells (RBCs). We derived and validated an individualized hemolysis correction equation in an attempt to reduce the current rejection rate of 14% at our institution.

METHODS

Intracellular NSE was measured in RBC lysates to determine concentration variability. A correction equation was derived, accounting for both RBC-derived NSE false-elevation and hemoglobin-derived signal quenching. The performance of this individualized correction was evaluated in intentionally hemolyzed samples and accuracy was compared to a generalized correction.

RESULTS

Significant inter-individual variability of RBC NSE was observed, with an almost two-fold range (15.7-28.5 ng NSE/mg Hb, p<0.001); intra-individual variability was insignificant. The individualized hemolysis correction equation derived: NSE(corr)=NSE(meas)-(Hb(serum))(NSE(RBCs/Hb))+0.0844(Hb(serum))+1.1 corrected 95% of the intentionally hemolyzed samples to within ±5 ng/ml of corresponding baseline NSE concentrations, compared to 74% using a generalized formula.

CONCLUSIONS

The individualized hemolysis correction provides increased accuracy in the estimation of true serum NSE concentrations for hemolyzed samples, compared to a generalized approach, by accounting for inter-individual RBC NSE variability. Incorporating this correction should reduce sample rejection rates and overall health care costs.

ERK phosphorylation is predictive of resistance to IGF-1R inhibition in small cell lung cancer

New therapies are critically needed to improve the outcome for patients with small cell lung cancer (SCLC). Insulin-like growth factor 1 receptor (IGF-1R) inhibition is a potential treatment strategy for SCLC: the IGF-1R pathway is commonly upregulated in SCLC and has been associated with inhibition of apoptosis and stimulation of proliferation through downstream signaling pathways, including phosphatidylinositol-3-kinase-Akt and mitogen-activated protein kinase. To evaluate potential determinants of response to IGF-1R inhibition, we assessed the relative sensitivity of 19 SCLC cell lines to OSI-906, a small molecule inhibitor of IGF-1R, and the closely related insulin receptor. Approximately one third of these cell lines were sensitive to OSI-906, with an IC50 < 1 μmol/L. Cell line expression of IGF-1R, IR, IGF-1, IGF-2, IGFBP3, and IGFBP6 did not correlate with sensitivity to OSI-906. Interestingly, OSI-906 sensitive lines expressed significantly lower levels of baseline phospho-ERK relative to resistant lines (P = 0.006). OSI-906 treatment resulted in dose-dependent inhibition of phospho-IGF-1R and phospho-Akt in both sensitive and resistant cell lines, but induced apoptosis and cell-cycle arrest only in sensitive lines. We tested the in vivo efficacy of OSI-906 using an NCI-H187 xenograft model and two SCLC patient xenografts in mice. OSI-906 treatment resulted in 50% tumor growth inhibition in NCI-H187 and 30% inhibition in the primary patient xenograft models compared with mock-treated animals. Taken together our data support IGF-1R inhibition as a viable treatment strategy for a defined subset of SCLC and suggest that low pretreatment levels of phospho-ERK may be indicative of sensitivity to this therapeutic approach.

α-Enolase, a multifunctional protein: its role on pathophysiological situations

α-Enolase is a key glycolytic enzyme in the cytoplasm of prokaryotic and eukaryotic cells and is considered a multifunctional protein. α-enolase is expressed on the surface of several cell types, where it acts as a plasminogen receptor, concentrating proteolytic plasmin activity on the cell surface. In addition to glycolytic enzyme and plasminogen receptor functions, α-Enolase appears to have other cellular functions and subcellular localizations that are distinct from its well-established function in glycolysis. Furthermore, differential expression of α-enolase has been related to several pathologies, such as cancer, Alzheimer's disease, and rheumatoid arthritis, among others. We have identified α-enolase as a plasminogen receptor in several cell types. In particular, we have analyzed its role in myogenesis, as an example of extracellular remodelling process. We have shown that α-enolase is expressed on the cell surface of differentiating myocytes, and that inhibitors of α-enolase/plasminogen binding block myogenic fusion in vitro and skeletal muscle regeneration in mice. α-Enolase could be considered as a marker of pathological stress in a high number of diseases, performing several of its multiple functions, mainly as plasminogen receptor. This paper is focused on the multiple roles of the α-enolase/plasminogen axis, related to several pathologies.

Potential application of non-small cell lung cancer-associated autoantibodies to early cancer diagnosis

To identify a panel of tumor associated autoantibodies which can potentially be used as biomarkers for the early diagnosis of non-small cell lung cancer (NSCLC). Thirty-five unique and in-frame expressed phage proteins were isolated. Based on the gene expression profiling, four proteins were selected for further study. Both receiver operating characteristic curve analysis and leave-one-out method revealed that combined measurements of four antibodies produced have better predictive accuracies than any single marker alone. Leave-one-out validation also showed significant relevance with all stages of NSCLC patients. The panel of autoantibodies has a high potential for detecting early stage NSCLC.

Mass spectrometry analysis of the post-translational modifications of alpha-enolase from pancreatic ductal adenocarcinoma cells

Enolase is a key glycolytic enzyme that catalyzes the dehydration of 2-phosphoglycerate to phosphoenolpyruvate. Recently, enolase was revealed as an important protein in pathophysiological processes since it was found on the surface of hematopoietic cells and overexpressed in several tumor cells. Our previous studies demonstrated that alpha-enolase is up-regulated in pancreatic ductal adenocarcinoma (PDAC). In this present work, we further characterized the alpha-enolase from PDAC and normal pancreatic duct cells by mass spectrometry using LTQ-Orbitrap and identified multiple post-translational modifications of alpha-enolase, such as phosphorylation, acetylation, and methylation. The result showed that more acetylated lysines, methylated aspartic acids, and glutamic acids were found in PDAC cells than that of normal pancreatic duct cells.

Lung cancer-associated auto-antibodies measured using seven amino acid peptides in a diagnostic blood test for lung cancer

Autoantibody profiling is a developing approach that incorporates immune recognition of myriad aberrant cancer proteins into a single diagnostic assay. We have previously described methodology to screen T7-phage NSCLC-cDNA libraries for phage-expressed proteins recognized by NSCLC-associated antibodies, and developed a multiplex assay that has excellent ability to discriminate NSCLC from control samples. This follow-up report describes the development and testing of a diagnostic autoantibody assay that uses seven amino-acid peptides as capture proteins. A random-peptide M13-phage library was screened for proteins recognized by cancer-associated antibodies. One hundred twenty-one NSCLC case and control samples were divided into two groups for training and validation, or alternately, evaluated sequentially in a leave-one-out analysis. Candidate antibody-markers were ranked by statistical discrimination between cases and controls. Receiver-Operating-Characteristic (ROC-AUC) suggested the predictive potential of various marker combinations. A five-marker combination (AUC = 0.982) afforded 90% sensitivity and 73% specificity in a training-and-testing strategy. Leave-one-out validation provided similar class prediction. Data confirm the potential of antibody profiling to provide high levels of cancer prediction. Random peptide libraries offer a universal source of capture proteins for antibody profiling that obviates the need for tumor-specific library construction and abrogates inherent problems with tumor heterogeneity during biomarker discovery.

A joint detection of CEA and CA-50 levels in saliva and serum of patients with tumors in oral region and salivary gland

OBJECTIVE

To detect the levels of carcinoembryonic antigen (CEA) and carcinoma associated antigen CA-50 in the patients with oral or salivary malignant tumors.

METHODS

The concentrations of salivary CEA and CA-50 were assayed in 80 patients of oral and salivary malignant tumors, 40 patients of benign tumors and 80 health controls. In 80 patients with malignant tumors, serum CEA and CA-50 were also assayed by enzyme-linked immunoabsorbent assay and immunoradiometric analysis, respectively.

RESULTS

Salivary CEA and CA-50 levels were significantly higher in malignant tumors than in benign tumors and in health controls, respectively (P < 0.001). Only 7 cases and 3 cases of 80 patients with malignant tumors were found having increased serum CEA and CA-50 levels, respectively.

CONCLUSIONS

The measurement of CEA and CA-50 levels in saliva were more sensitive than in serum. This may be more useful as prognostic indicators in early diagnosis of oral and salivary malignant tumors.

CEA levels in serum and BAL in patients suffering from lung cancer: correlation with individuals presenting benign lung lesions and healthy volunteers

BACKGROUND

Carcinoembryonic antigen (CEA) is a tumor marker belonging to the immunoglobulin gene superfamily of adhesion molecules. CEA is synthesized by epithelial and tumor cells. In this study, CEA levels in sera and bronchoalveolar lavage fluid (BAL) were measured in patients with malignant lung cancer and benign lung diseases.

METHODS

In the present study CEA was measured in serum using IRMA methods and in bronchoalveolar lavage of individuals undergoing fiberoptic bronchoscopy. Fifty patients with lung cancer (G1), 20 patients with benign lung lesions (G2), and a control group consisted of 20 individuals (G3) were enrolled in the study.

RESULTS

We found that serum CEA levels were significantly higher in G1 compared to G2 and G3 (p < 0.01). No significant difference in serum CEA levels was found between smokers and nonsmokers in any of the three groups studied. CEA was significantly higher in G1 BAL (p < 0.05) compared to G2 and G3 BAL. Furthermore, a statistically significant difference was found in CEA levels in BAL between smokers and nonsmokers of G2.

CONCLUSIONS

CEA levels in BAL of normal individuals may be influenced by smoking and other factors that affect lung epithelial cell function. Thus, CEA measurement in BAL alone has little value in the diagnosis of malignancy. BAL CEA levels in smokers of G2 are found significantly higher compared with nonsmokers of the same group and healthy individuals. Smokers of G2 have to be followed up carefully for the possibility of lung cancer growth.

Targeting receptor tyrosine kinase signalling in small cell lung cancer (SCLC): what have we learned so far?

Small cell lung cancer (SCLC) is an aggressive form of lung cancer, which represents 13% of all cases and is strongly associated with cigarette smoking. The survival of SCLC patients is dismal and has not greatly improved in the last 20 years, despite advances in chemotherapy regimens and a better understanding of SCLC biology. The development of resistance to chemotherapy and metastasis are commonly recognized as important causes of poor clinical outcome in SCLC. Targeting receptor tyrosine kinase (RTK) signalling represents an attractive approach to develop new drugs for SCLC, in view of the accumulating data demonstrating that polypeptide growth factors play a key role in driving SCLC cell proliferation, chemoresistance and metastasis. The insulin-like growth factor-I receptor (IGF-IR), c-Kit, vascular endothelial growth factor receptor (VEGFR) and epidermal growth factor receptor (EGFR) have been identified as potential drug targets in SCLC. Moreover, downstream signalling mediators of RTKs, such as phosphoinositide 3-kinase (PI3K)/Akt and the mammalian target of rapamycin (mTOR) may also represent attractive candidate molecules for anti-cancer therapies in SCLC. Here we will review the available data concerning results with RTK inhibitors in SCLC and the clinical trials undertaken to investigate the potential of these compounds as anti-tumour agents in SCLC.

Multiplex Measurement of Seven Tumor Markers Using an Electrochemical Protein Chip

An electrochemical immunosensor for performing multianalyte measurements of tumor markers is described. The sensor consisted of an array of immunosensing electrodes fabricated on a glass substrate. Each electrode contained a different immobilized antigen and was capable of measuring a specific tumor marker using electrochemical enzyme-based competitive immunoassay. Using this arrangement, multiple analytes could be measured simultaneously by performing the technical operations for a single assay. The biosensor was used to measure the concentrations of seven important tumor markers: AFP, ferritin, CEA, hCG-beta, CA 15-3, CA 125, and CA 19-9. The sensor had excellent precision and accuracy and was comparable in performance to single-analyte ELISAs (1.9-8.1% interassay CV; <2 ng/mL (or units/mL) detection limit for most analytes). Multianalyte assays provide significant advantages over single-analyte tests in terms of cost per test, labor, test throughput, and convenience. We anticipate that chip-based sensors, as described herein, will be suitable for the mass production of economical, miniaturized lab-on-a-chip devices that will have applications in a wide range of clinical, environmental, and biodefense applications.

Subcellular and Functional Proteomic Analysis of the Cellular Responses Induced by Helicobacter pylori

Helicobacter pylori infection is a crucial factor in the pathogenesis of several digestive disorders, including peptic ulcers, chronic gastritis, and gastric cancer. Moreover H. pylori induces disease-specific protein expression in gastric epithelial cells. The aim of the present study was to characterize proteins differentially expressed in H. pylori-infected gastric epithelial AGS cells. An in vitro model was established using a multiplicity of infection of 100 and evaluating the effectiveness of H. pylori infection by functional analyses. Changes in protein patterns were identified using a proteomic approach consisting of two-dimensional fluorescence difference gel electrophoresis and mass spectrometry. The expression of many proteins was found to be altered, and 28 of these were identified and classified as protein synthesis- and folding-related proteins, cytoskeleton proteins, metabolic enzymes, transcription- and translation-related proteins, angiogenesis/metastasis-related proteins, cell communication/signal transduction-related proteins, or others (oxygen-regulated protein and oncoprotein). The expression profiles of eight of these proteins, laminin gamma-1 chain precursor, valosin-containing protein, heat shock 70-kDa protein, mitochondrial matrix protein P1, FK506-binding protein 4, T-complex protein 1, enolase alpha, and 14-3-3 beta were further examined in cancerous and paired surrounding normal tissues by immunoblot assay and immunohistochemical staining to identify molecular targets that may be involved in the pathogenesis of H. pylori-induced gastric diseases. On the basis of our results, valosin-containing protein, mitochondrial matrix protein P1, T-complex protein 1, enolase alpha, and 14-3-3 beta may play a crucial role in H. pylori-induced gastric carcinogenesis by mediating antiapoptotic and proliferative responses.

Effects of hemolysis and storage condition on neuron-specific enolase (NSE) in cerebrospinal fluid and serum: implications in clinical practice

The concentration of neuron-specific enolase (NSE) in serum and cerebrospinal fluid (CSF) has been used as a biomarker in some cancers and, more recently, in neurodegenerative diseases. Pre-analytical conditions are very important for the quality of returned results. In this study, we evaluated the effects of storage conditions (temperature and duration of storage) and hemolysis on the concentration of NSE in serum and CSF. Our results demonstrate that samples for NSE measurement may be stored at -80 degrees C for no more than 6 months in the case of CSF and 9 months in the case of serum samples. Even invisible hemolysis may increase NSE levels in samples. Consequently, an index of hemolysis should be determined before deciding whether or not to perform NSE measurement.

Cell cycle related proteins as prognostic parameters in radically resected non-small cell lung cancer

BACKGROUND

Experimental evidence suggests that lung cancer development and progression can be linked to an increased proliferation rate.

AIMS/METHODS

To evaluate the immunohistochemical expression of seven components of the cell cycle machinery in a series of well characterised non-small cell lung cancer (NSCLC) specimens (n = 105).

RESULTS

Multivariate analysis revealed that simultaneous loss of expression of three of these factors--cyclin D1, the cyclin dependent kinase inhibitor p16, and the tumour suppressor retinoblastoma protein Rb2/p130--correlated with survival, confirming the hypothesis that the cyclin D1-p16-retinoblastoma tumour suppressor pathway is inactivated in most lung cancer samples.

CONCLUSIONS

These results suggest that loss of control of cell cycle checkpoints is a common occurrence in lung cancer and support the idea that functional cooperation between different cell cycle regulatory proteins constitutes another level of regulation in cell growth control and tumour suppression.

Using protein microarray as a diagnostic assay for non-small cell lung cancer

RATIONALE

Phenotypic and genotypic heterogeneity of lung cancer likely precludes the identification of a single predictive marker and suggests the importance of identifying and measuring multiple markers.

OBJECTIVES

We describe the use of a fluorescent protein microarray to identify and measure multiple non-small cell lung cancer-associated antibodies and show how simultaneous measurements can be combined into a single diagnostic assay.

METHODS

T7 phage cDNA libraries of non-small cell lung cancer were first biopanned with plasma samples from normal subjects and patients with non-small cell lung cancer to enrich the component of tumor-associated proteins, and then applied to microarray slides. Two hundred twelve immunogenic phage-expressed proteins were identified from roughly 4,000 clones, using high-throughput screening with patient plasmas and assayed with 40 cancer and 41 normal plasma samples. Twenty patient and 21 normal plasma samples were randomly chosen and used for statistical determination of the predictive value of each putative marker. Statistical analysis identified antibody reactivity to seven unique phage-expressed proteins that were significantly different (p < 0.01) between patient and normal groups. The remaining 20 patient and 20 normal plasma samples were used as an independent test of the predictive ability of the selected markers.

MAIN RESULTS

Measurements of the 5 most predictive phage proteins were combined in a logistic regression model that achieved 90% sensitivity and 95% specificity in prediction of patient samples, whereas leave-one-out statistical analysis achieved 88.9% diagnostic accuracy among all 81 samples.

CONCLUSION

Our data indicate that antibody profiling is a promising approach that could achieve high diagnostic accuracy for non-small cell lung cancer.

Prognostic Value of the Carcinoembryonic Antigen Found in Pleural Lavage Fluid From Patients With Lung Carcinoma

OBJECTIVE

To detect the tumor marker carcinoembryonic antigen (CEA) in pleural lavage fluid taken during surgery from patients with pulmonary carcinoma without associated pleural effusion and assess its possible prognostic implications.

PATIENTS AND METHODS

A prospective, observational study was undertaken to include consecutive patients who underwent surgical treatment for lung carcinoma in which pleural lavage was performed prior to closure of the thoracic cavity (study group). The same techniques and measurements were used in patients undergoing thoracotomy for benign disease (control group). The preoperative blood level of CEA was also quantified.

RESULTS

In the study group, the median CEA levels in blood and pleural lavage fluid were 2.90 ng/mL and 0.40 ng/mL respectively; these figures are higher than those corresponding to the control group. A CEA level of 0.30 ng/mL in pleural lavage fluid was established as a cutoff point, based on the corresponding receiver operating characteristic curve, with a sensitivity of 68.4% and a specificity of 35.7%. A graph of survival in relation to this cutoff point revealed a statistically significant effect (P<.05).

CONCLUSIONS

It is possible to detect CEA in pleural lavage fluid from the thoracic cavity of patients with lung carcinoma. The values obtained are higher than those found in fluid from patients without neoplastic disease, and this parameter functions as an independent predictor of disease course.

Cellular stress-related protein expression in Helicobacter pylori-infected gastric epithelial AGS cells

Helicobacter pylori infection leads to gastroduodenal inflammation, peptic ulceration, and gastric carcinoma. Moreover, H. pylori may induce disease-specific protein expression in gastric epithelial cells. The present study was aimed at determining differentially expressed proteins in H. pylori-infected gastric epithelial AGS cells. AGS cells were treated with H. pylori at a bacterium/cell ratio of 300:1 for 12 h. Altered protein patterns as separated by two-dimensional electrophoresis using pH gradients of 4-7 were conclusively identified by matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) analysis of the peptide digests. Four differentially expressed proteins, whose expression levels were increased by more than two-fold in H. pylori-infected cells, were analyzed. These proteins (14-3-3 protein alpha/beta, cullin homolog 3, alpha-enolase, ezrin) are known to be related to cell proliferation, cell adhesion, and carcinogenesis, and may be mediated by cellular stress, such as reactive oxygen species. In conclusion, the identification of these differentially expressed proteins provide valuable information for the understanding of the pathophysiologic mechanisms of H. pylori-induced gastric diseases, and may be useful as prognostic indices of H. pylori-related gastric disorders.