Inhibition of Raf-MEK-ERK and hypoxia pathways by Phyllanthus prevents metastasis in human lung (A549) cancer cell line

The effectiveness of blood-activating and stasis-transforming traditional Chinese medicines (BAST) in lung cancer progression-a comprehensive review

ETHNOPHARMACOLOGICAL RELEVANCE

Blood-activating and stasis-transforming traditional Chinese medicines (BAST) are a class of herbs that have the effect of dilating blood vessels and dispersing stagnation. Modern pharmaceutical research has demonstrated that they are capable of improving hemodynamics and micro-flow, resist thrombosis and promote blood flow. BAST contain numerous active ingredients, which can theoretically regulate multiple targets at the same time and have a wide range of pharmacological effects in the treatment of diseases including human cancers. Clinically, BAST have minimal side effects and can be used in combination with Western medicine to improve patients' quality of life, lessen adverse effects and minimize the risk of recurrence and metastasis of cancers.

AIM OF THE REVIEW

We aimed to summarize the research progression of BAST on lung cancer in the past five years and present a prospect for the future. Particularly, this review further analyzes the effects and molecular mechanisms that BAST inhibit the invasion and metastasis of lung cancer.

MATERIALS AND METHODS

Relevant studies about BSAT were collected from PubMed and Web of science.

RESULTS

Lung cancer is one of the malignant tumors with the highest mortality rate. Most patients with lung cancer are diagnosed at an advanced stage and are highly susceptible to metastasis. Recent studies have shown that BAST, a class of traditional Chinese medicine (TCM) with the function of opening veins and dispersing blood stasis, significantly improve hemodynamics and microcirculation, prevent thrombosis and promote blood flow, and thereby inhibiting the invasion and metastasis of lung cancer. In the current review, we analyzed 51 active ingredients extracted from BAST. It was found that BAST and their active ingredients contribute to the prevention of invasion and metastasis of lung cancer through multiple mechanisms, such as regulation of EMT process, specific signaling pathway and metastasis-related genes, tumor blood vessel formation, immune microenvironment and inflammatory response of tumors.

CONCLUSIONS

BSAT and its active ingredients have showed promising anticancer activity and significantly inhibit the invasion and metastasis of lung cancer. A growing number of studies have realized their potential clinical significance in the therapy of lung cancer, which will provide substantial evidences for the development of new TCM for lung cancer therapy.

A Review: Mechanism of Phyllanthus urinaria in Cancers-NF-κB, P13K/AKT, and MAPKs Signaling Activation

Phyllanthus urinaria has been characterized for its several biological and medicinal effects such as antiviral, antibacterial, anti-inflammatory, anticancer, and immunoregulation. In recent years, Phyllanthus urinaria has demonstrated potential to modulate the activation of critical pathways such as NF-κB, P13K/AKT, and ERK/JNK/P38/MAPKs associated with cell growth, proliferation, metastasis, and apoptotic cell death. To date, there is much evidence indicating that modulation of cellular signaling pathways is a promising approach to consider in drug development and discovery. Thus, therapies that can regulate cancer-related pathways are longed-for in anticancer drug discovery. This review's focus is to provide comprehensive knowledge on the anticancer mechanisms of Phyllanthus urinaria through the regulation of NF-κB, P13K/AKT, and ERK/JNK/P38/MAPKs signaling pathways. Thus, the review summarizes both in vitro and in vivo effects of Phyllanthus urinaria extracts or bioactive constituents with emphasis on tumor cell apoptosis. The literature information was obtained from publications on Google Scholar, PubMed, Web of Science, and EBSCOhost. The key words used in the search were "Phyllanthus" or "Phyllanthus urinaria" and cancer. P. urinaria inhibits cancer cell proliferation via inhibition of NF-κB, P13K/AKT, and MAPKs (ERK, JNK, P38) pathways to induce apoptosis and prevents angiogenesis. It is expected that understanding these fundamental mechanisms may help stimulate additional research to exploit Phyllanthus urinaria and other natural products for the development of novel anticancer therapies in the future.

RN181 regulates the biological behaviors of oral squamous cell carcinoma cells via mediating ERK/MAPK signaling pathway

OBJECTIVE

To explore the role of RN181 in the pathogenesis of oral squamous cell carcinoma (OSCC) cells via mediating ERK/MAPK signaling.

METHODS

The expression of RN181 was detected in OSCC tissues and cells. CAL27 and SCC-15 cells were divided into Control, Empty, RN181, si-RN181, U0126 (an inhibitor of ERK/MAPK pathway) and si-RN181 + U0126 groups. MTT was used to determine cell proliferation, flow cytometry to determine cell cycle and apoptosis, Transwell assay and wound healing test to determine cell invasion and migration, respectively. Western blotting was used to measure the protein expression. Furthermore, a xenograft tumor model was established to observe the effect of RN181 on the in vivo growth of OSCC cells.

RESULTS

RN181 was down-regulated in OSCC tissues and cells. As compared to the Control group, CAL27 and SCC-15 cells in the RN181 group and U0126 group presented with decreases in the proliferation, invasion and migration, but increases in the cell ratio at the G0/G1 phase and apoptosis, while the p-ERK 1/2/ERK 1/2 was down-regulated. Cells in the si-RN181 group manifested the opposite changes. U0126 could reverse the positive effect of si-RN181 on the growth of OSCC cells. In vivo experiment demonstrated that the tumor growth and weight were reduced in the RN181 group, with decreased Ki67 positive expression and elevated TUNEL positive cells.

CONCLUSION

RN181 was down-regulated in OSCC, and it could inhibit the proliferation, invasion and migration, cause the G0/G1 arrest, while promote the apoptosis of OSCC cells via inhibiting ERK/MAPK pathway.

Isorhamnetin inhibited migration and invasion via suppression of Akt/ERK-mediated epithelial-to-mesenchymal transition (EMT) in A549 human non-small-cell lung cancer cells

In the present study, we investigated the potential effects of Isorhamnetin on the growth and metastasis of A549 human lung cancer cells, as well as the underlying mechanism. Treatment with Isorhamnetin exhibited a dose- and time-dependent inhibition on A549 cell proliferation. Furthermore, the cell adhesion and Transwell assay showed that treatment with Isorhamnetin (2.5, 5, and 10 μM) for 48 h resulted in a significant inhibition effect on cell adhesion, invasion and migration of A549 cells, depending on concentration, which was associated with the suppression of matrix metalloproteinase (MMP)-2 and MMP-9 activity and protein expression. Moreover, Isorhamnetin effectively suppressed the expressions of epithelial-to-mesenchymal transition (EMT) markers, as evidenced by the down-regulation of N-cadherin, vimentin and snail, as well as up-regulation of E-cadherin protein expression. Additionally, these inhibitions were mediated by interrupting AKT/ERK1/2 signaling pathways. Taken together, the results of the current study demonstrated that Isorhamnetin may become a good anti-metastastic agent against lung cancer A549 cell line by the suppression of EMT via interrupting Akt/ERK1/2 signaling pathway.

Alterations of Human Plasma Proteome Profile on Adaptation to High-Altitude Hypobaric Hypoxia

For individuals migrating to or residing permanently in high-altitude regions, environmental hypobaric hypoxia is a primary challenge that induces several physiological or pathological responses. It is well documented that human beings adapt to hypobaric hypoxia via some protective mechanisms, such as erythropoiesis and overproduction of hemoglobin; however, little is known on the alterations of plasma proteome profiles in accommodation to high-altitude hypobaric hypoxia. In the present study, we investigated differential plasma proteomes of high altitude natives and lowland normal controls by a TMT-based proteomic approach. A total of 818 proteins were identified, of which 137 were differentially altered. Bioinformatics (including GO, KEGG, protein-protein interactions, etc.) analysis showed that the differentially altered proteins were basically involved in complement and coagulation cascades, antioxidative stress, and glycolysis. Validation results demonstrated that CCL18, C9, PF4, MPO, and S100A9 were notably up-regulated, and HRG and F11 were down-regulated in high altitude natives, which were consistent with TMT-based proteomic results. Our findings highlight the contributions of complement and coagulation cascades, antioxidative stress, and glycolysis in acclimatization to hypobaric hypoxia and provide a foundation for developing potential diagnostic or/and therapeutic biomarkers for high altitude hypobaric hypoxia-induced diseases.

FLOT1 promotes tumor development, induces epithelial-mesenchymal transition, and modulates the cell cycle by regulating the Erk/Akt signaling pathway in lung adenocarcinoma

Background

FLOT1 is a scaffolding protein of lipid rafts that is believed to be involved in numerous cellular processes. However, few studies have explored the function of FLOT1 in the development of lung adenocarcinoma (LUAD) and the underlying mechanisms of FLOT1 activity.

Methods

FLOT1 knockdown and overexpression models were constructed via lentivirus. Cell growth, invasion, migration, and apoptosis were detected to evaluate the role of FLOT1 in LUAD development. Epithelial–mesenchymal transition (EMT) and cell cycle regulatory markers were then examined. Finally, the influence of FLOT1 on the Erk/Akt signaling pathway was investigated.

Results

FLOT1 promoted cell growth, invasion, and migration and inhibited cell apoptosis. In addition, FLOT1 induced EMT and modulated the cell cycle by activating the Erk/Akt signaling pathway.

Conclusion

The findings indicate a significant role of FLOT1 in LUAD development. Targeting FLOT1 may be a potential therapeutic strategy for LUAD.

Not Everyone Fits the Mold: Intratumor and Intertumor Heterogeneity and Innovative Cancer Drug Design and Development

Disruptive innovations in medicine are game-changing in nature and bring about radical shifts in the way we understand human diseases, their treatment, and/or prevention. Yet, disruptive innovations in cancer drug design and development are still limited. Therapies that cure all cancer patients are in short supply or do not exist at all. Chief among the causes of this predicament is drug resistance, a mechanism that is much more dynamic than previously understood. Drug resistance has limited the initial success experienced with biomarker-guided targeted therapies as well. A major contributor to drug resistance is intratumor heterogeneity. For example, within solid tumors, there are distinct subclones of cancer cells, presenting profound complexity to cancer treatment. Well-known contributors to intratumor heterogeneity are genomic instability, the microenvironment, cellular genotype, cell plasticity, and stochastic processes. This expert review explains that for oncology drug design and development to be more innovative, we need to take into account intratumor heterogeneity. Initially thought to be the preserve of cancer cells, recent evidence points to the highly heterogeneous nature and diverse locations of stromal cells, such as cancer-associated fibroblasts (CAFs) and cancer-associated macrophages (CAMs). Distinct subpopulations of CAFs and CAMs are now known to be located immediately adjacent and distant from cancer cells, with different subpopulations exerting different effects on cancer cells. Disruptive innovation and precision medicine in clinical oncology do not have to be a distant reality, but can potentially be achieved by targeting these spatially separated and exclusive cancer cell subclones and CAF subtypes. Finally, we emphasize that disruptive innovations in drug discovery and development will likely come from drugs whose effect is not necessarily tumor shrinkage.

A Review of the Phytochemistry and Pharmacology of Phyllanthus urinaria L

The genus Phyllanthus (L.) is one of the most important groups of plants belonging to the Phyllantaceae family. Phyllanthus urinaria (L.) is an annual perennial herbal species found in tropical Asia, America, China, and the Indian Ocean islands. P. urinaria is used in folk medicine as a cure to treat jaundice, diabetes, malaria, and liver diseases. This review provides traditional knowledge, phytochemistry, and biological activities of P. urinaria. The literature reviewed for this article was obtained from the Web of Science, SciFinder, PubMed, ScienceDirect, and Google Scholar journal papers published prior to December 2017. Phytochemical investigations reveal that the plant is a rich source of lignans, tannins, flavonoids, phenolics, terpenoids, and other secondary metabolites. Pharmacological activities include anticancer, hepatoprotective, antidiabetic, antimicrobial, and cardioprotective effects. Thus, this present review summarizes the phytochemical constituents and their biological activities including biological studies on various crude extracts and fractions both in vitro and in vivo, and on clinical trial information about P. urinaria. This review compiles 93 naturally occurring compounds from P. urinaria along with their structures and pharmacological activities. The review is expected to stimulate further research on P. urinaria, and its pharmacological potential to yield novel therapeutic agents.

What Has Come out from Phytomedicines and Herbal Edibles for the Treatment of Cancer?

Several modern treatment strategies have been adopted to combat cancer with the aim of minimizing toxicity. Medicinal plant-based compounds with the potential to treat cancer have been widely studied in preclinical research and have elicited many innovations in cutting-edge clinical research. In parallel, researchers have eagerly tried to decrease the toxicity of current chemotherapeutic agents either by combining them with herbals or in using herbals alone. The aim of this article is to present an update of medicinal plants and their bioactive compounds, or mere changes in the bioactive compounds, along with herbal edibles, which display efficacy against diverse cancer cells and in anticancer therapy. It describes the basic mechanism(s) of action of phytochemicals used either alone or in combination therapy with other phytochemicals or herbal edibles. This review also highlights the remarkable synergistic effects that arise between certain herbals and chemotherapeutic agents used in oncology. The anticancer phytochemicals used in clinical research are also described; furthermore, we discuss our own experience related to semisynthetic derivatives, which are developed based on phytochemicals. Overall, this compilation is intended to facilitate research and development projects on phytopharmaceuticals for successful anticancer drug discovery.

The synergistic effect of propofol and ulinastatin suppressed the viability of the human lung adenocarcinoma epithelial A549 cell line

Ulinastatin and propofol (PPF) are recognized for their anticancer properties. The aim of the present study was to evaluate the synergistic antitumor effect of PPF followed by ulinastatin against A549 cells. In MTT assays, PPF (10, 20 and 30 µM) followed by 200 U/ml ulinastatin was more effective at inhibiting A549 cell viability compared with PPF (10, 20 and 30 µM) or 200 U/ml ulinastatin. PPF (10, 20 and 30 µM) followed by 200 U/ml ulinastatin treatments synergistically increased the number of S cells and synergistically reduced the number of G2/M cells associated with PPF stimulation in a dose-dependent manner. Western blot analysis demonstrated that the antitumor effect of PPF followed by 200 U/ml ulinastatin treatments were associated with the downregulated expression of extracellular signal-regulated kinase 1 and 2 phosphorylation (p-ERK1/2) and matrix metalloproteinases 2 (MMP-2). In conclusion, these data demonstrated that PPF (20 and 30 µM) followed by 200 U/ml ulinastatin treatments synergistically stimulated a significant proportion of A549 cells in S phase. Furthermore, the combination synergistically reduced a significant proportion of A549 cells in G2/M phase and synergistically suppressed the viability of A549 cells, which was possibly related regulation of the expression of p-ERK1/2 and MMP-2 in A549 cells.

Caveolin-1 promotes Ewing sarcoma metastasis regulating MMP-9 expression through MAPK/ERK pathway

Ewing sarcoma (ES) is a bone and soft tissue sarcoma affecting mostly children and young adults. Caveolin-1 (CAV1) is a well-known target of EWS/FLI1, the main driver of ES, with an oncogenic role in ES. We have previously described how CAV1 is able to induce metastasis in ES via matrix metalloproteinase-9 (MMP-9). In the present study we showed how CAV1 silencing in ES reduced MEK1/2 and ERK1/2 phosphorylation. Accordingly, chemical inhibition of MEK1/2 resulted in reduction in MMP-9 expression and activity that correlated with reduced migration and invasion. IQ Motif Containing GTPase Activating Protein 1 (IQGAP1) silencing reduced MEK1/2 and ERK1/2 phosphorylation and MMP-9 expression. Furthermore, IQGAP1 silenced cells showed a marked decrease in their migratory and invasive capacity. We demonstrated that CAV1 and IQGAP1 localize in close proximity at the cellular edge, thus IQGAP1 could be the connecting node between CAV1 and MEK/ERK in ES metastatic phenotype. Analysis of the phosphorylation profile of CAV1-silenced cells showed a decrease of p-ribosomal protein S6 (RPS6). RPS6 can be phosphorylated by p90 ribosomal S6 kinases (RSK) proteins. CAV1-silenced cells showed reduced levels of p-RSK1 and treatment with U0126 provoked the same effect. Despite not affecting ERK1/2 and RPS6 phosphorylation status neither MMP-9 expression nor activity, RSK1 silencing resulted in a reduced migratory and invasive capacity in vitro and reduced incidence of metastases in vivo in a novel orthotopic model. The present work provides new insights into CAV1-driven metastatic process in ES unveiling novel key nodes.

Hsa-miR-623 suppresses tumor progression in human lung adenocarcinoma

Our previous study revealed that Ku80 was overexpressed in lung cancer tissues and hsa-miR-623 regulated the Ku80 expression; however, the detailed function of hsa-miR-623 in lung cancer was unclear. We identified that hsa-miR-623 bound to the 3'-UTR of Ku80 mRNA, thus significantly decreasing Ku80 expression in lung adenocarcinoma cells. Hsa-miR-623 was downregulated in lung adenocarcinoma tissues compared with corresponding non-tumorous tissues, and its expression was inversely correlated with Ku80 upregulation. Downregulation of hsa-miR-623 was associated with poor clinical outcomes of lung adenocarcinoma patients. Hsa-miR-623 suppressed lung adenocarcinoma cell proliferation, clonogenicity, migration and invasion in vitro. Hsa-miR-623 inhibited xenografts growth and metastasis of lung adenocarcinoma in vivo. Ku80 knockdown in lung adenocarcinoma cells suppressed tumor properties in vitro and in vivo similar to hsa-miR-623 overexpression. Further, hsa-miR-623 overexpression decreased matrix metalloproteinase-2 (MMP-2) and MMP-9 expression levels, with decreased ERK/JNK phosphorylation. Inhibition of hsa-miR-623 or overexpression of Ku80 promoted lung adenocarcinoma cell invasion, activated ERK/JNK phosphorylation and increased MMP-2/9 expressions, which could be reversed by ERK kinase inhibitor or JNK kinase inhibitor. In summary, our results showed that hsa-miR-623 was downregulated in lung adenocarcinoma and suppressed the invasion and metastasis targeting Ku80 through ERK/JNK inactivation mediated downregulation of MMP-2/9. These findings reveal that hsa-miR-623 may serve as an important therapeutic target in lung cancer therapy.

Xanthohumol inhibits the extracellular signal regulated kinase (ERK) signalling pathway and suppresses cell growth of lung adenocarcinoma cells

Aberrant activation of the Ras/MEK/ERK signaling pathway has been frequently observed in non-small-cell lung carcinoma (NSCLC) and its important role in cancer progression and malignant transformation has been documented. Hence, the ERK1/2 kinase cascade becomes a potential molecular target in cancer treatment. Xanthohumol (XN, a prenylated chalcone derived from hope cones) is known to possess a broad spectrum of chemopreventive and anticancer activities. In our studies, the MTT and BrdU assays revealed that XN demonstrated greater antiproliferative activity against A549 lung adenocarcinoma cells than against the lung adenocarcinoma H1563 cell line. We observed that XN was able to suppress the activities of ERK1/2 and p90RSK kinases, followed by inhibition of phosphorylation and activation of the CREB protein. Additionally, the XN treatment of the cancer cells caused upregulation of key cell cycle regulators p53 and p21 as well as downregulation of cyclin D1. As a result, the cytotoxic effect of XN was attributed to the cell cycle arrest at G1 phase and induction of apoptosis indicated by increased caspase-3 activity. Thus, XN might be a promising anticancer drug candidate against lung carcinomas.

Suppression of ERK1/2 and hypoxia pathways by four Phyllanthus species inhibits metastasis of human breast cancer cells

Chemotherapies remain far from ideal due to drug resistance; therefore, novel chemotherapeutic agents with higher effectiveness are crucial. The extracts of four Phyllanthus species, namely Phyllanthus niruri, Phyllanthus urinaria, Phyllanthus watsonii, and Phyllanthus amarus, were shown to induce apoptosis and inhibit metastasis of breast carcinoma cells (MCF-7). The main objective of this study was to determine the pathways utilized by these four Phyllanthus species to exert anti-metastatic activities. A cancer 10-pathway reporter was used to investigate the pathways affected by the four Phyllanthus species. Results indicated that these Phyllanthus species suppressed breast carcinoma metastasis and proliferation by suppressing matrix metalloprotein 2 and 9 expression via inhibition of the extracellular signal-related kinase (ERK) pathway. Additionally, inhibition of hypoxia-inducible factor 1-α in the hypoxia pathway caused reduced vascular endothelial growth factor and inducible nitric oxide synthase expression, resulting in anti-angiogenic effects and eventually anti-metastasis. Two-dimensional gel electrophoresis identified numerous proteins suppressed by these Phyllanthus species, including invasion proteins, anti-apoptotic protein, protein-synthesis proteins, angiogenic and mobility proteins, and various glycolytic enzymes. Our results indicated that ERK and hypoxia pathways are the most likely targets of the four Phyllanthus species for the inhibition of MCF-7 metastasis.

Tspan9 inhibits the proliferation, migration and invasion of human gastric cancer SGC7901 cells via the ERK1/2 pathway

Tetraspanins are a heterogeneous group of 4-transmembrane proteins that recruit other cell surface receptors and signaling proteins into tetraspanin-enriched microdomains (TEMs). TEMs of various types are involved in the regulation of cell growth, migration and invasion of several tumor cell types, both as suppressors or promotors. Tetraspanin 9 (Tspan9, NET-5, PP1057), a member of the transmembrane 4 superfamily (TM4SF) of tetraspanins, reportedly regulates platelet function in concert with other platelet tetraspanins and their associated proteins. Our previous study demonstrated that Tspan9 is also expressed in gastric cancer (GC), but the role of Tspan9 in GC has not been well characterized. In this study, we investigated the influence of Tspan9 on proliferation, migration and invasion of human gastric cancer SGC7901 cells using CCK-8 assay, cell cycle analysis, wound-healing assay and Transwell assay. Western blot analysis and ELISA assay were also performed to identify the potential mechanisms involved. The proliferation, migration and invasion of human gastric cancer SGC7901 cells were significantly inhibited by overexpression of Tspan9. In addition, Tspan9 downregulated the phosphorylation of extracellular signal-regulated kinases 1 and 2 (ERK1/2) and the secretion levels of proteins related to tumor metastasis, such as matrix metalloproteinase-9 (MMP-9) and urokinase plasminogen activator (uPA). Our study indicated that Tspan9 inhibited SGC7901 cell proliferation, migration and invasion through the ERK1/2 pathway.

MiR-451 suppresses cell proliferation and metastasis in A549 lung cancer cells

Recent study showed that inflammation was related to lung cancer. However, the exact cause of lung inflammation leading to carcinogenesis is unknown. MicroRNAs (miRNAs) are a group of endogenous non-coding small RNAs that regulate the activity of targeted mRNAs by inflammatory response in many diseases. MiR-451 was reported to relate to the development of lung cancer and metastasis of glioma. But the effect of miR-451 on cell proliferation, migration, and invasion of lung cancer is not really clear. In order to explore the molecular mechanism of the occurrence and development of lung cancer, we investigated the effect of human miR-451 on the proliferation, invasion, and metastasis in lung cancer cell line A549. The miR-451 expression construct was generated into pGenesil-1.1 and transfected into A549 cells. Results showed that the recombinant vectors were verified by sequencing. And miR-451 was over-expressed in A549 by real-time RT PCR. Furthermore, the proliferation, invasion, and metastasis of the cells in miR-451 group were inhibited significantly compared with those in control and A549 groups by MTT assay, Transwell invasion assay, and wound-healing assay. And the lung cancer metastasis factors (MMP-2, MMP-9, VEGF, and CXCR4) were decreased in miR-451 group by Western blot. Moreover, it was proved that inflammation-related gene-PSMB8 was a target for miR-451 by bioinformatics analysis and dual-luciferase reporter assay. And the protein expressions of PSMB8 and NOS2 were decreased in miR-451 group compared with those in control and A549 groups. Therefore, our findings indicated that miR-451 related to PSMB8/NOS2 inflammatory factors may suppress the development and migration of lung cancer, providing evidence for the role of miR-451 in lung cancer.

Proteomic identification of novel differentiation plasma protein markers in hypobaric hypoxia-induced rat model

Background

Hypobaric hypoxia causes complex changes in the expression of genes, including stress related genes and corresponding proteins that are necessary to maintain homeostasis. Whereas most prior studies focused on single proteins, newer methods allowing the simultaneous study of many proteins could lead to a better understanding of complex and dynamic changes that occur during the hypobaric hypoxia.

Methods

In this study we investigated the temporal plasma protein alterations of rat induced by hypobaric hypoxia at a simulated altitude of 7620 m (25,000 ft, 282 mm Hg) in a hypobaric chamber. Total plasma proteins collected at different time points (0, 6, 12 and 24 h), separated by two-dimensional electrophoresis (2-DE) and identified using matrix assisted laser desorption ionization time of flight (MALDI-TOF/TOF). Biological processes that were enriched in the plasma proteins during hypobaric hypoxia were identified using Gene Ontology (GO) analysis. According to their properties and obvious alterations during hypobaric hypoxia, changes of plasma concentrations of Ttr, Prdx-2, Gpx -3, Apo A-I, Hp, Apo-E, Fetub and Nme were selected to be validated by Western blot analysis.

Results

Bioinformatics analysis of 25 differentially expressed proteins showed that 23 had corresponding candidates in the database. The expression patterns of the eight selected proteins observed by Western blot were in agreement with 2-DE results, thus confirming the reliability of the proteomic analysis. Most of the proteins identified are related to cellular defense mechanisms involving anti-inflammatory and antioxidant activity. Their presence reflects the consequence of serial cascades initiated by hypobaric hypoxia.

Conclusion/Significance

This study provides information about the plasma proteome changes induced in response to hypobaric hypoxia and thus identification of the candidate proteins which can act as novel biomarkers.