Proteomics-based identification of haptoglobin as a novel plasma biomarker in oral squamous cell carcinoma

Risk of head and neck cancer in relation to blood inflammatory biomarkers in the Swedish AMORIS cohort

Background

Inflammation is critically involved in the development of human cancer, and blood inflammatory biomarkers have been proposed to indicate the risk of different cancer types.

Methods

Using the Swedish Apolipoprotein-Related Mortality Risk (AMORIS) Cohort (N=812,073), we first performed a time-to-event analysis to evaluate the association of the baseline level of 12 blood inflammatory biomarkers measured during 1985-1996 with the subsequent risk of head and neck cancer (HNC) identified through the nationwide Swedish Cancer Register until end of 2020. A nested case-control study was further conducted to demonstrate the longitudinal trends of the studied biomarkers during the 30-year period prior to diagnosis of HNC.

Results

In the time-to-event analysis, we identified a total of 2,510 newly diagnosed HNC cases. There was an increased risk of HNC per standard deviation (SD) increase of haptoglobin (hazard ratio [HR]: 1.25; 95% confidence interval [CI]: 1.21-1.30), leukocytes (HR: 1.22; 95%CI: 1.17-1.28), sedimentation rate (HR: 1.17; 95%CI: 1.07-1.29), and monocytes (HR: 1.34; 95%CI: 1.07-1.68) at baseline, after adjustment for age, sex, fasting status, occupational status, and country of birth. In contrast, there was a decreased risk of HNC per SD increase of lymphocytes in % (HR: 0.85; 95%CI: 0.73-0.99) and lymphocyte-to-monocyte ratio (LMR) (HR: 0.81; 95%CI: 0.69-0.95) at baseline. In the nested case-control study using repeatedly measured biomarker levels, we found that individuals with HNC had consistently higher levels of haptoglobin, leukocytes, sedimentation rate, and monocytes, as well as consistently lower levels of lymphocytes in % and LMR, during the 30-year period prior to diagnosis, compared to controls.

Conclusion

Based on a cohort of more than half a million participants with up to 35 years of follow-up, our findings provide solid evidence supporting the presence of alterations in blood inflammatory biomarkers during the decades before diagnosis of HNC.

Comprehensive Review on Development of Early Diagnostics on Oral Cancer with a Special Focus on Biomarkers

One of the most frequent head and neck cancers is oral cancer, with less than half of those diagnosed surviving five years. Despite breakthroughs in the treatment of many other cancers, the prognosis for people with OSCC remains dismal. The conventional methods of detection include a thorough clinical examination, biochemical investigations, and invasive biopsies. Early identification and treatment are important for a better chance of extending a patient’s life. Early diagnosis may be possible by identifying biomarkers in biological fluids. Currently, the primary method for diagnosing oral lesions is a visual oral examination; however, such a technique has certain drawbacks, as individuals are recognized after their cancer has advanced to a severe degree. The first section of this review discusses several diagnostic techniques for cancer detection, while the second section discusses the present state of knowledge about known existing predictive markers for the timely identification of malignant lesions, as well as disease activity tracking. The aim of the paper is to conduct a critical review of existing oral cancer diagnostic processes and to consider the possible application of innovative technology for early detection. This might broaden our diagnostic choices and enhance our capacity to identify and treat oral malignant tumors more effectively.

Epithelial integrity, junctional complexes, and biomarkers associated with intestinal functions

An intact intestinal barrier is crucial for immune homeostasis and its impairment activates the immune system and may result in chronic inflammation. The epithelial cells of the intestinal barrier are connected by tight junctions, which form an anastomosing network sealing adjacent epithelial cells. Tight junctions are composed of transmembrane and cytoplasmic scaffolding proteins. Transmembrane tight junction proteins at the apical-lateral membrane of the cell consist of occludin, claudins, junctional adhesion molecules, and tricellulin. Cytoplasmic scaffolding proteins, including zonula occludens, cingulin and afadin, provide a direct link between transmembrane tight junction proteins and the intracellular cytoskeleton. Each individual component of the tight junction network closely interacts with each other to form an efficient intestinal barrier. This review aims to describe the molecular structure of intestinal epithelial tight junction proteins and to characterize their organization and interaction. Moreover, clinically important biomarkers associated with impairment of gastrointestinal integrity are discussed.

Serum HSP90-Alpha and Oral Squamous Cell Carcinoma : A Prospective Biomarker

AIM

Current study aims to perform differential protein expression analysis of serum samples from Oral squamous cell carcinoma (OSCC) patients and healthy controls in search of potential diagnostic and/or prognostic biomarker(s).

OBJECTIVE

OSCC is diagnosed late, resulting in poor survival and high mortality. Identification of non-invasive prognostic biomarker is of utmost importance for early diagnosis and proper management of the disease; hence we used proteomic approach to identify potential biomarkers from serum.

METHODS

Serum samples (OSCC n=45 and control n=30) were depleted and proteins were separated using 2-D gel electrophoresis followed by identification by mass spectrometric analysis. Gene expression analysis of identified proteins in malignant and normal tissue was also performed to complement proteomics studies.

RESULTS

Among differentially expressed proteins, a noteworthy observation was up regulation of Heat shock protein alpha (HSP90α) from serum of oral cancer patients. We also observed elevated levels of Haptoglobin (HP) along with down regulation of Type II keratin cytoskeletal 1(KRT1) and serum Albumin (ALB) in oral cancer patients. Gene expression studies of identified proteins in malignant and normal tissue revealed a similar pattern with the exception of KRT1. We believe that elevated levels of serum HSP90 alpha might be used as a potential biomarker.

CONCLUSION

Our findings suggest the contribution of HSP90 alpha and other identified proteins in oral pathology as pro/anti apoptotic modulators, thus they are being considered as predictive biomarkers.

c-MYC-directed NRF2 drives malignant progression of head and neck cancer via glucose-6-phosphate dehydrogenase and transketolase activation

Rationale: NRF2, a redox sensitive transcription factor, is up-regulated in head and neck squamous cell carcinoma (HNSCC), however, the associated impact and regulatory mechanisms remain unclear.

Methods: The protein expression of NRF2 in HNSCC specimens was examined by IHC. The regulatory effect of c-MYC on NRF2 was validated by ChIP-qPCR, RT-qPCR and western blot. The impacts of NRF2 on malignant progression of HNSCC were determined through genetic manipulation and pharmacological inhibition in vitro and in vivo. The gene-set enrichment analysis (GSEA) on expression data of cDNA microarray combined with ChIP-qPCR, RT-qPCR, western blot, transwell migration/ invasion, cell proliferation and soft agar colony formation assays were used to investigate the regulatory mechanisms of NRF2.

Results: NRF2 expression is positively correlated with malignant features of HNSCC. In addition, carcinogens, such as nicotine and arecoline, trigger c-MYC-directed NRF2 activation in HNSCC cells. NRF2 reprograms a wide range of cancer metabolic pathways and the most notable is the pentose phosphate pathway (PPP). Furthermore, glucose-6-phosphate dehydrogenase (G6PD) and transketolase (TKT) are critical downstream effectors of NRF2 that drive malignant progression of HNSCC; the coherently expressed signature NRF2/G6PD/TKT gene set is a potential prognostic biomarker for prediction of patient overall survival. Notably, G6PD- and TKT-regulated nucleotide biosynthesis is more important than redox regulation in determining malignant progression of HNSCC.

Conclusions: Carcinogens trigger c-MYC-directed NRF2 activation. Over-activation of NRF2 promotes malignant progression of HNSCC through reprogramming G6PD- and TKT-mediated nucleotide biosynthesis. Targeting NRF2-directed cellular metabolism is an effective strategy for development of novel treatments for head and neck cancer.

Artificial Intelligence to Decode Cancer Mechanism: Beyond Patient Stratification for Precision Oncology

The multitude of multi-omics data generated cost-effectively using advanced high-throughput technologies has imposed challenging domain for research in Artificial Intelligence (AI). Data curation poses a significant challenge as different parameters, instruments, and sample preparations approaches are employed for generating these big data sets. AI could reduce the fuzziness and randomness in data handling and build a platform for the data ecosystem, and thus serve as the primary choice for data mining and big data analysis to make informed decisions. However, AI implication remains intricate for researchers/clinicians lacking specific training in computational tools and informatics. Cancer is a major cause of death worldwide, accounting for an estimated 9.6 million deaths in 2018. Certain cancers, such as pancreatic and gastric cancers, are detected only after they have reached their advanced stages with frequent relapses. Cancer is one of the most complex diseases affecting a range of organs with diverse disease progression mechanisms and the effectors ranging from gene-epigenetics to a wide array of metabolites. Hence a comprehensive study, including genomics, epi-genomics, transcriptomics, proteomics, and metabolomics, along with the medical/mass-spectrometry imaging, patient clinical history, treatments provided, genetics, and disease endemicity, is essential. Cancer Moonshot℠ Research Initiatives by NIH National Cancer Institute aims to collect as much information as possible from different regions of the world and make a cancer data repository. AI could play an immense role in (a) analysis of complex and heterogeneous data sets (multi-omics and/or inter-omics), (b) data integration to provide a holistic disease molecular mechanism, (c) identification of diagnostic and prognostic markers, and (d) monitor patient's response to drugs/treatments and recovery. AI enables precision disease management well beyond the prevalent disease stratification patterns, such as differential expression and supervised classification. This review highlights critical advances and challenges in omics data analysis, dealing with data variability from lab-to-lab, and data integration. We also describe methods used in data mining and AI methods to obtain robust results for precision medicine from "big" data. In the future, AI could be expanded to achieve ground-breaking progress in disease management.

Evaluation of Haptoglobin Genotype and Some Risk Factors of Cancer in Patients with Early Stage Esophageal Cancer

INTRODUCTION

Esophageal cancer is one of the most lethal gastrointestinal cancers that has a complex and diverse etiology, with several genetic and nutritional factors involved in its etiology. The purpose of this study was to investigate the type of haptoglobin genotype and its relationship with some nutritional and biochemical risk factors affecting the prevalence of esophageal cancer in patients with early stage esophageal cancer.

MATERIALS AND METHODS

In this study, 44 patients (20 males and 24 females) with early stage esophageal cancer and 44 healthy subjects, classified as control group, (19 males and 25 females) were selected. Haptoglobin (HP) genotype was determined employing PCR technique. Nutritional data were analyzed using standard food frequency questionnaire (FFQ) method. Serum levels of malondialdehyde (MDA), nitrate and nitrite were measured employing the colorimetric method. Serum levels of p53 protein were measured using the enzyme-linked immunosorbent assay (ELISA) technique.

RESULTS

The results of our study showed for the first time that HP1-1 genotype was the most prevalent genotype in esophageal cancer patients in Golestan province, Iran. HP2-2 genotype was the most frequent in the control group. Serum levels of MDA were significantly higher in the patients' group compared to the control group (P˂0.001). Weight and body mass index (BMI) were significantly lower in the patients' group than the control group (P<0.01). Food frequency analysis revealed that the consumption of fruits and vegetables in the patients' group was lower than that of the control group (P<0.05).

CONCLUSION

The results of our study showed for the first time that HP1-1 genotype is the dominant genotype in patients with esophageal cancer in Golestan province. As well, modification of nutritional pattern and consumption of high level of antioxidant compounds can be effective in reducing the prevalence of esophageal cancer in this region.

Proteomic Profiling for Serum Biomarkers in Mice Exposed to Ionizing Radiation

In response to large-scale radiological incidents, rapid, accurate, and early triage biodosimeters are urgently required. In this study, we investigated candidate radiation-responsive biomarkers using proteomics approaches in mouse models. A total of 452 dysregulated proteins were identified in the serum samples of mice exposed to 0, 2, 5.5, 7, and 8 Gy at 6, 24, and 72 hours postirradiation. Ninety-eight proteins, including 46 at 6 hours, 36 at 24 hours, and 36 at 72 hours, were identified as radiation-responsive proteins (RRPs). Gene Ontology analysis showed the RRPs were involved in proteolysis, extracellular space, hydrolase activity, and carbohydrate binding. Kyoto Encyclopedia of Genes and Genome enrichment showed the RRPs were regulated in "the pentose phosphate pathway," "the proteasome," and "AGE-RAGE signaling in diabetic complications." There were 3 proteins changed and overlapped at all the 3 time points, 8 proteins changed at 6 and 24 hours, 4 proteins changed at 24 and 72hours, and 2 proteins changed at both 6 and 72 hours. Of these proteins, ORM2, HP, SAA1, SAA2, MBL2, COL1A1, and APCS were identified as candidate biomarkers for biodosimeter-based diagnosis through Pearson correlation analysis.

Inflammatory Markers and MicroRNAs: The Backstage Actors Influencing Prognosis in Colorectal Cancer Patients

BACKGROUND

Colorectal cancer (CRC) remains a deadly disease, afflicting the lives of millions worldwide. The prognosis of CRC patients is best predicted by surgical resection and pathological analysis of specimens. Emerging evidence has attributed a significant role to inflammatory markers and microRNAs (miRNAs) in the prognosis and survival of CRC patients.

AIM

Here, we review the literature on inflammatory markers and miRNAs with an established role on survival rates, response to systemic chemotherapy, and other clinic-pathological parameters in CRC patients.

RESULTS

Our literature review revealed a critical role of inflammatory markers—specifically, the acute-phase proteins, inflammatory cytokines, and blood cell ratios—on prognostic outcomes in CRC patients. MiRNAs, on the other hand, were useful in predicting prognosis and clinical response and accordingly stratifying CRC patients for optimal drug selection.

CONCLUSION

These biomarkers are easily measured in routine blood exams and can be used in adjunct to the tumor-node-metastasis (TNM) staging system to identify high-risk patients and those who are more likely to benefit from chemotherapy and other targeted therapies. However, more prospective studies are needed for the validation of these discussed prognostic and predictive biomarkers.

Proteomic analysis of oral cancer reveals new potential therapeutic targets involved in the Warburg effect

Activation of peroxisome proliferator-activated receptor alpha (PPARα) has been reported to disrupt tumour metabolism and to promote anticancer activity through interfering with the Warburg effect. This study is to investigate whether Warburg effect-related proteins also could be identified in oral tumour lesions and to explore the functional significance of PPARα in metabolic shift. Five pairs of tongue tumour tissues and adjacent reference tissues obtained from 4-NQO/arecoline induced mouse model were analyzed by 2-d-gel-electrophoresis and LC-MS. Further, the hexokinase II level, pyruvate dehydrogenase (PDH) activity, and metabolites of glycolysis and TCA cycle were all examined in order to validate the effect of PPARα on metabolic shift. Changes in protein expression levels revealed that seven proteins, which were involved in glycolysis, the tricarboxylic acid cycle, and the respiratory chain, were down-regulated in tumour tissues. We found that activation of PPARα through fenofibrate could inhibit oral cancer cell growth and switch the way of energy production from the Warburg effect to oxidative phosphorylation. Fenofibrate induced a reduction of hexokinase II protein levels, increases in PDH activity and metabolites of the TCA cycle, and an impairment of ATP production. These findings suggested that activation of the PPARα to reprogram the metabolic pathway might impair the Warburg effect and trigger cancer cell death. The study provides a novel view of changes in protein expression profiles involved in the Warburg effect during oral tumourigenesis. Activation of the PPARα to impair the Warburg effect might offer a new strategy for oral cancer treatment.

Dithiothreitol-based protein equalization technology to unravel biomarkers for bladder cancer

This study aimed to assess the benefits of dithiothreitol (DTT)-based sample treatment for protein equalization to assess potential biomarkers for bladder cancer. The proteome of plasma samples of patients with bladder carcinoma, patients with lower urinary tract symptoms (LUTS) and healthy volunteers, was equalized with dithiothreitol (DTT) and compared. The equalized proteomes were interrogated using two-dimensional gel electrophoresis and matrix assisted laser desorption ionization time of flight mass spectrometry. Six proteins, namely serum albumin, gelsolin, fibrinogen gamma chain, Ig alpha-1 chain C region, Ig alpha-2 chain C region and haptoglobin, were found dysregulated in at least 70% of bladder cancer patients when compared with a pool of healthy individuals. One protein, serum albumin, was found overexpressed in 70% of the patients when the equalized proteome of the healthy pool was compared with the equalized proteome of the LUTS patients. The pathways modified by the proteins differentially expressed were analyzed using Cytoscape. The method here presented is fast, cheap, of easy application and it matches the analytical minimalism rules as outlined by Halls. Orthogonal validation was done using western-blot. Overall, DTT-based protein equalization is a promising methodology in bladder cancer research.

Peroxiredoxin-2 and zinc-alpha-2-glycoprotein as potentially combined novel salivary biomarkers for early detection of oral squamous cell carcinoma using proteomic approaches

No effective screening method is available for oral squamous cell carcinoma (OSCC) that is recognized to influence by environmental factors as well as human papillomavirus (HPV) and Epstein-Barr virus (EBV). Therefore, we sought to identify salivary biomarkers for screening of OSCC with or without HPV and/or EBV infection. Saliva, lesion and oral exfoliated cells were collected from OSCC patients and cancer-free controls (CFCs) and grouped depending on their HPV- and EBV-infection status. Salivary protein was precipitated and subjected to 2-dimensional gel electrophoresis. Differential expression of proteins was identified by mass spectrometry and validated by Western blotting. Distinctive expression patterns of salivary proteins were detected in OSCC as compared with CFCs. Levels of peroxiredoxin-2 (PRDX-2) and zinc-alpha-2-glycoprotein (ZAG) were significantly up-regulated in OSCC cases (p<0.001) relative to CFCs. Similarly, these proteins were also up-regulated in lesion cells compared with oral exfoliated cells (p<0.001). However, the expression patterns of these proteins were not significantly influenced by patient histories (risk factors). In combination, these proteins yielded the highest discriminatory power (AUC=0.999), sensitivity (100%), and specificity (98.77%) in distinguishing the early stages of OSCC. The detection of PRDX-2 combining with ZAG protein could potentially be used as salivary biomarkers for early screening of OSCC.

SIGNIFICANCE

Our findings demonstrate a useful of combined detection of PRDX-2 and ZAG as a salivary biomarker for the early detection of OSCC.

Serum haptoglobin as a novel molecular biomarker predicting colorectal cancer hepatic metastasis

Early detection of liver metastasis is important for improving colorectal cancer (CRC) patient survival. Our previous studies showed haptoglobin was highly expressed in primary CRC tissues, especially in heterochronous metastatic cases. Here, we assessed the potential of serum haptoglobin (sHP) as a biomarker for early detection of CRC liver metastasis by evaluating the sHP in 475 CRC patients and 152 healthy volunteers. In the training set (250 cases), sHP level in CRC-M1 (1773.18 ± 690.25 ng/mL) were significantly increased as compared to in CRC-M0 (1544.37 ± 1497.65 ng/mL) or healthy (917.76 ± 571.59 ng/mL). And the high sHP level was correlated with poor survival. Logistic regression analysis revealed that sHP, serum carcinoembryonic antigen (sCEA) and serum carbohydrate antigen 19.9 (sCA19.9) level were the significant parameters for detecting liver metastasis. In leave-one-out-cross-validation, these three markers resulted in 89.1% sensitivity and 85.8% specificity for hepatic metastasis detection. In an independent test set (225 cases), receiver operating characteristic curve analysis of sHP in CRC liver metastasis showed an area under the curve of 0.735, with a sensitivity of 87.2% and a specificity of 59.9%. Combination of sHP, sCEA and sCA19.9 improved diagnostic accuracy to 0.880, with a sensitivity of 88.5% and a specificity of 87.8%. Silencing of HP by specific shRNA significantly inhibited the LOVO and SW620 cell invasion, and suppressed xenograft tumor invasive growth. In summary, these results demonstrate that sHP is associated with poor prognosis of CRC patients and that HP promotes colorectal cancer cell invasion. sHP combining with sCA19.9 and sCEA may be used as accurate predictors of CRC liver metastasis.

Discovery of potential serum protein biomarkers for lymph node metastasis in oral cancer

BACKGROUND

The purpose of our study was to identify serum protein biomarkers for node-positive oral squamous cell carcinoma (OSCC). Biomarkers indicating lymph node metastasis provides a valuable classification methodology to optimize treatment plans for patients with OSCC.

METHODS

Quantitative serum proteomic analysis of OSCCs with either node-positive or node-negative disease was performed with tandem mass spectrometry and isobaric tagging for relative and absolute quantitation (iTRAQ). Immunoassays were used to validate a panel of candidate protein biomarkers and receiver operating characteristic (ROC) analysis was used to evaluate the performance of the candidate biomarkers.

RESULTS

A total of 282 serum proteins were quantified between node-positive and node-negative OSCCs with the proteomic approach. Four candidate biomarkers, gelsolin, fibronectin, angiotensinogen, and haptoglobin, were validated in an independent group of patients with node-positive or node-negative OSCC. The best candidate biomarker, gelsolin, yielded a ROC value of 89% for node-positive OSCC, although the sample size for validation is relatively small. Fibronectin, gelsolin, and angiotensinogen were also found to be differentially expressed between cancer cell lines of node-positive and node-negative cancer origin.

CONCLUSION

Our studies suggest that testing of serum protein biomarkers might help detect lymph node metastasis of oral cancer. Because of limited sample size in our studies, long-term longitudinal studies with large populations of individuals with oral cancer are needed to validate these potential biomarkers.

Novel technologies for oral squamous carcinoma biomarkers in diagnostics and prognostics

BACKGROUND

Oral squamous cell carcinoma (OSCC) is a highly prevalent malignant pathology of the oral cavity. Despite the significant progress accomplished in the field of OSCC, the diagnosis is performed mostly in advanced stages; thus, novel biomarkers need to be developed for the diagnostic and prognostic of this malignancy. Many new technologies are used to provide indispensable information related to the pathogenesis of OSCC. The molecular profiling studies that incorporate genetic and epigenetic alterations need to be integrated in clinical practice as routine approaches to facilitate a better diagnostic and prognostic.

REVIEW

In this review, the authors present a summary of these novel technologies in the field of genomics, transcriptomics or proteomics, capable of generating data related to personalized diagnostic and treatment.

Single chain precursor prohaptoglobin promotes angiogenesis by upregulating expression of vascular endothelial growth factor (VEGF) and VEGF receptor2

Prohaptoglobin (proHp) is processed into mature haptoglobin via site-specific cleavage. Although haptoglobin has been well studied, the functions of proHp remain unclear. We investigated the angiogenic action of proHp in endothelial cells, demonstrating that proHp upregulated vascular endothelial growth factor (VEGF) and VEGF receptor 2 (VEGFR2) expression and endothelial sprouting and branching. ProHp-induced sprouting was attenuated by a VEGFR2 inhibitor. Moreover, proHp was detected in sera of cancer patients by immunoprecipitation and Western blot. These findings indicate that proHp promotes angiogenesis via VEGF/VEGFR2 signalling, and serum proHp level may be a useful biomarker for diseases associated with angiogenesis.

Identification of host-immune response protein candidates in the sera of human oral squamous cell carcinoma patients

One of the most common cancers worldwide is oral squamous cell carcinoma (OSCC), which is associated with a significant death rate and has been linked to several risk factors. Notably, failure to detect these neoplasms at an early stage represents a fundamental barrier to improving the survival and quality of life of OSCC patients. In the present study, serum samples from OSCC patients (n = 25) and healthy controls (n = 25) were subjected to two-dimensional gel electrophoresis (2-DE) and silver staining in order to identify biomarkers that might allow early diagnosis. In this regard, 2-DE spots corresponding to various up- and down-regulated proteins were sequenced via high-resolution MALDI-TOF mass spectrometry and analyzed using the MASCOT database. We identified the following differentially expressed host-specific proteins within sera from OSCC patients: leucine-rich α2-glycoprotein (LRG), alpha-1-B-glycoprotein (ABG), clusterin (CLU), PRO2044, haptoglobin (HAP), complement C3c (C3), proapolipoprotein A1 (proapo-A1), and retinol-binding protein 4 precursor (RBP4). Moreover, five non-host factors were detected, including bacterial antigens from Acinetobacter lwoffii, Burkholderia multivorans, Myxococcus xanthus, Laribacter hongkongensis, and Streptococcus salivarius. Subsequently, we analyzed the immunogenicity of these proteins using pooled sera from OSCC patients. In this regard, five of these candidate biomarkers were found to be immunoreactive: CLU, HAP, C3, proapo-A1 and RBP4. Taken together, our immunoproteomics approach has identified various serum biomarkers that could facilitate the development of early diagnostic tools for OSCC.

Utility of models of the gastrointestinal tract for assessment of the digestion and absorption of engineered nanomaterials released from food matrices

Engineered metal/mineral, lipid and biochemical macromolecule nanomaterials (NMs) have potential applications in food. Methodologies for the assessment of NM digestion and bioavailability in the gastrointestinal tract are nascent and require refinement. A working group was tasked by the International Life Sciences Institute NanoRelease Food Additive project to review existing models of the gastrointestinal tract in health and disease, and the utility of these models for the assessment of the uptake of NMs intended for food. Gastrointestinal digestion and absorption could be addressed in a tiered approach using in silico computational models, in vitro non-cellular fluid systems and in vitro cell culture models, after which the necessity of ex vivo organ culture and in vivo animal studies can be considered. Examples of NM quantification in gastrointestinal tract fluids and tissues are emerging; however, few standardized analytical techniques are available. Coupling of these techniques to gastrointestinal models, along with further standardization, will further strengthen methodologies for risk assessment.

Measurement of serum paraoxonase activity and MDA concentrations in patients suffering with oral squamous cell carcinoma

BACKGROUND

Oxidative stress is associated with many diseases including cancer. Oral squamous cell carcinoma (OSCC) is a prevalent cancer involving oral cavity. We evaluate the activity of paraoxonase 1 (PON1) in serum samples of subjects suffering from OSCC along with malondialdehyde (MDA) levels, a marker for oxidative stress. Antioxidant status in OSCC may reflect the role of oxidative imbalance in the disease.

METHODS

Forty-five patients suffering with OSCC and 30 healthy controls were selected for the study. Serum paraoxonase (PON) and arylesterase (ARE) activities were measured in subjects suffering from OSCC and their healthy counterparts. To examine the status of lipid peroxidation, MDA concentrations were estimated and a correlation was determined between PON activities and MDA concentrations. MDA expression in cancer and normal adjacent tissue was studied through immunohistochemical (IHC) analysis. Total reactive oxygen species (ROS) level was determined in serum from normal and diseased subjects. Our results revealed that both PON and ARE activities of PON1 were significantly decreased in OSCC patients. Serum MDA concentrations were inversely correlated to PON activity. Immunohistochemical analysis showed a higher expression of MDA in cancerous tissue. Total ROS levels were found to be significantly elevated in cancer subjects.

CONCLUSIONS

Along with other antioxidants, PON levels may act as an indicator of oxidative stress in cancer.

Quantitative proteomic analysis by iTRAQ for identification of candidate biomarkers in plasma from acute respiratory distress syndrome patients

Acute respiratory distress syndrome (ARDS) is a major cause of morbidity and mortality in critical patients. Proteomic analysis of plasma from individuals with ARDS could elucidate new biomarkers for diagnosis and pathophysiology and identify potential ARDS treatment targets. In this study, we recruited 26 patients (15 controls, 11 ARDS). The ARDS group was subdivided into two groups depending on the type of injury: (1) direct lung injury (AD) and (2) indirect lung injury (AI). Using iTRAQ (isobaric tags for relative and absolute quantitation) analysis, we identified 2429 peptides representing 132 plasma proteins. Among these, 16 were differentially expressed in ARDS patients, including 11 overlapping proteins between the AI and AD group and 5 AI-specific proteins. Protein annotation revealed that lipid transport and complement activation were significantly enriched in the biological process category, and lipid transporter, transporter, and serine-type peptidase activities were significantly enriched in the molecular function category. IPA (Ingenuity Pathway Analysis) signaling pathways revealed that the overlapping proteins were involved in a variety of signaling pathways, including those underlying acute phase response; liver X receptor/retinoid X receptor (LXR/RXR) and farnesoid X (FXR)/RXR activation; clathrin-mediated endocytosis; atherosclerosis; interleukin (IL)-12; complement system; and cytokine, nitric oxide, and reactive oxygen species production in macrophages. We present the first proteomic analysis of ARDS plasma using the iTRAQ approach. Our data provide new biomarker candidates and shed light on potential pathological mechanisms underlying ARDS.

Proteomics: methodologies and applications to the study of human diseases

Proteomic approach has allowed large-scale studies of protein expression in different tissues and body fluids in discrete conditions and/or time points. Recent advances of methodologies in this field have opened new opportunities to obtain relevant information on normal and abnormal processes occurring in the human body. In the current report, the main proteomics techniques and their application to human disease study are reviewed.

Proteomics-based identification of plasma biomarkers in oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is an aggressive cancer and its occurrence is closely related to betel nut chewing in Taiwan. However, there are few prognostic and diagnostic biomarkers for this disease especially for its association with betel nut chewing. Recent progresses in quantitative proteomics have offered opportunities to discover plasma proteins as biomarkers for tracking the progression and for understanding the molecular mechanisms of OSCC. In present study, plasma samples from OSCC patients with at least 5-year history of betel nut chewing and healthy donors were analyzed by fluorescence 2D-DIGE-based proteomic analysis. Totally, 38 proteins have been firmly identified representing 13 unique gene products. These proteins mainly function in inflammatory responses (such as fibrinogen gamma chain) and transport (Apolipoprotein A-I). Additionally, the current quantitative proteomic approach has identified numerous OSCC biomarkers including fibrinogen (alpha/beta/gamma) chain, haptoglobin, leucine-rich alpha-2-glycoprotein and ribosomal protein S6 kinase alpha-3 (RSK2) which have not been reported and may be associated with the progression and development of the disease. In summary, this study reports a comprehensive patient-based proteomic approach for the identification of potential plasma biomarkers in OSCC. The potential of utilizing these markers for screening and treating OSCC warrants further investigations.

Correspondence between salivary proteomic pattern and clinical course in primary Sjögren syndrome and non-Hodgkin's lymphoma: a case report

Background

In the last years human proteomic has represented a promising tool to promote the communication between basic and clinical science.

Methods

To explore the correspondence between salivary proteomic profile and clinical response, herein, we used a proteomic approach to analyse the whole saliva of a patient with primary Sjögren's Syndrome (pSS) and non-Hodgkin's-MALT type parotid lymphoma before, during and after a standard treatment with cyclophosphamide (CTX) and rituximab (RTX). To identify any discriminatory therapeutic salivary biomarker patient's whole saliva was collected at the baseline, after the fourth infusion of rituximab, and on remission and analysed combining two-dimensional electrophoresis (2DE) and MALDI-TOF/TOF mass spectrometry.

Results

Proteomic results obtained from the comparison of salivary samples indicated several qualitative and quantitative modifications in the salivary expression of putative albumin, immunoglobulin J chain, Ig kappa chain C region, alpha-1-antitrypsin, haptoglobin and Ig alpha-1 chain C region.

Conclusion

This study suggests that clinical and functional changes of the salivary glands driven by autoimmune and lymphoproliferative processes might be reflected in patients' whole saliva proteins, shedding new light on the potential usefulness of salivary proteomic analysis in the identification of prognostic and therapeutic biomarkers for patients with pSS and non Hodgkin's lymphomas.

Fucosylated glycoproteomic approach to identify a complement component 9 associated with squamous cell lung cancer (SQLC)

Human lung cancer is a major cause of cancer mortality worldwide. Understanding the pathophysiological features and the development of novel biomarkers for diagnosis as well as treatment are major tasks. In the present study, sera from ten SQLC patients and healthy control (HEC) were collected and pooled, respectively. The pooled sera were depleted via an immunoaffinity method and further subjected to fucosylation enrichment. Enriched fucosylated glycoproteins were resolved by SDS-PAGE and subsequently analyzed by LC-ESI-MS/MS. From comparative proteomic analysis, we selected the C9 protein. C9 protein levels were validated by Western blot, protein arrays and the fucosylation levels of C9 by hybrid lectin ELISA (HLE) in the sera of 120 HEC and 118 SQLC patients. The C9 protein level was 6.4-fold higher in SQLC patients compared to HEC, as determined by Western blot analysis. The results were concurrently confirmed by a protein array that showed a C9 level significantly higher in SQLC patients, as compared to HEC, with a sensitivity of 53% and a specificity of 89%. C9 fucosylation levels were significantly higher in SQLC patients compared to HEC (p<0.05) when tested by HLE. These findings suggest that C9 and fucosylated form could serve as a useful marker for SQLC.

Zonulin and its regulation of intestinal barrier function: the biological door to inflammation, autoimmunity, and cancer

The primary functions of the gastrointestinal tract have traditionally been perceived to be limited to the digestion and absorption of nutrients and to electrolytes and water homeostasis. A more attentive analysis of the anatomic and functional arrangement of the gastrointestinal tract, however, suggests that another extremely important function of this organ is its ability to regulate the trafficking of macromolecules between the environment and the host through a barrier mechanism. Together with the gut-associated lymphoid tissue and the neuroendocrine network, the intestinal epithelial barrier, with its intercellular tight junctions, controls the equilibrium between tolerance and immunity to non-self antigens. Zonulin is the only physiological modulator of intercellular tight junctions described so far that is involved in trafficking of macromolecules and, therefore, in tolerance/immune response balance. When the finely tuned zonulin pathway is deregulated in genetically susceptible individuals, both intestinal and extraintestinal autoimmune, inflammatory, and neoplastic disorders can occur. This new paradigm subverts traditional theories underlying the development of these diseases and suggests that these processes can be arrested if the interplay between genes and environmental triggers is prevented by reestablishing the zonulin-dependent intestinal barrier function. This review is timely given the increased interest in the role of a "leaky gut" in the pathogenesis of several pathological conditions targeting both the intestine and extraintestinal organs.

Fenofibrate exhibits a high potential to suppress the formation of squamous cell carcinoma in an oral-specific 4-nitroquinoline 1-oxide/arecoline mouse model

The excessive use of areca nut and/or tobacco may induce the production of free radicals and reactive oxygen species, which affect the lipid contents of the cell membrane and are possibly involved in tumorigenic processes in the oral cavity. The aim of this study was to investigate the therapeutic efficacy of fenofibrate (0.1% or 0.3%, w/w), a ligand of the peroxisome proliferator-activated receptor alpha (PPARα), in a 4-nitroquinoline 1-oxide (4-NQO)/arecoline-induced oral cancer mouse model. The carcinogen, 4-NQO/arecoline, was administrated to C57BL/6JNarl mice for 8weeks followed by fenofibrate treatment for 12 or 20weeks. After 28weeks, changes in serum lipids, the multiplicity of tumor lesions, and tumor sizes were determined together with changes in the immunohistochemical expressions of PPARα, acetyl-coenzyme A carboxylase (ACC), the epidermal growth factor receptor (EGFR), and cyclooxygenase-2 (COX2). The results showed that when compared to the 4-NQO/arecoline only group, 0.3% fenofibrate treatment increased serum total cholesterol, low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) levels. 0.3% fenofibrate treatment suppressed the incidence rate of tongue lesions, reduced the multiplicity of squamous cell carcinoma (SCC), decreased the tumor size, and increased the immunoreactivity of EGFR and COX2 in oral dysplasia but decreased EGFR and COX2 expressions in SCC. These findings indicated that fenofibrate reduced the tumor incidence rate and suppressed the tumor progression into SCC and that these molecular events might be linked to the EGFR and COX2 regulatory pathways. We suggest that fenofibrate provides a new strategy for preventing oral tumor progression.