ABSTRACT
Obesity-induced chronic liver inflammation is a hallmark of nonalcoholic steatohepatitis (NASH)-an aggressive form of nonalcoholic fatty liver disease. However, it remains unclear how such a low-grade, yet persistent, inflammation is sustained in the liver. Here, we show that the macrophage phagocytic receptor TREM2, induced by hepatocyte-derived sphingosine-1-phosphate, was required for efferocytosis of lipid-laden apoptotic hepatocytes and thereby maintained liver immune homeostasis. However, prolonged hypernutrition led to the production of proinflammatory cytokines TNF and IL-1ß in the liver to induce TREM2 shedding through ADAM17-dependent proteolytic cleavage. Loss of TREM2 resulted in aberrant accumulation of dying hepatocytes, thereby further augmenting proinflammatory cytokine production. This ultimately precipitated a vicious cycle that licensed chronic inflammation to drive simple steatosis transition to NASH. Therefore, impaired macrophage efferocytosis is a previously unrecognized key pathogenic event that enables chronic liver inflammation in obesity. Blocking TREM2 cleavage to restore efferocytosis may represent an effective strategy to treat NASH.
Subject(s)
Non-alcoholic Fatty Liver Disease , Overnutrition , Humans , Non-alcoholic Fatty Liver Disease/pathology , Overnutrition/pathology , Liver/pathology , Inflammation/pathology , Obesity/pathology , Membrane Glycoproteins , Receptors, ImmunologicABSTRACT
Protein acetylation modification controlled by acetyltransferases (HATs) and histone deacetylases (HDACs) regulates multiple biologic processes including cell proliferation and migration. HDAC inhibitors (HDACi) are currently used as a promising epigenetic-based therapy for cancer treatment. Of the anticancer activity, accumulating evidence has shown that HDACi can enhance cell migration in subset of cancer cells. Thus, there is a critical need to identify such counter anticancer activity to HDACi in different cancer cell types and elucidate the rational in order to develop appropriate combination therapies in cancer treatment. In seeking to address the effect of HDACi on esophageal squamous cell carcinoma (ESCC) cells migration, trichostatin A (TSA), a canonical HDACi targeting class I and class II HDACs, was used. Here, we report the discovery that TSA augmented ESCC cells migration by increasing the acetylation of nuclear factor-κB/RelA at lysine 310 (K310). To elucidate the mechanism by which TSA promotes the migration of ESCC cells, plasmid of RelA K310R, a mutant precluding acetylation at K310, was transfected into ESCC cells. Blocking acetylation of RelA at K310 significantly arrogated TSA-induced cell migration. Mechanistic investigations revealed that TSA increased the level of acetylated RelA at K310 (RelA K310ac), thereby increasing the level of epithelia-mesenchymal transition (EMT) transcription factor slug mRNA, which in turn induced EMT. Overall, this study indicates that TSA promotes ESCC cells migration by RelA K310ac-slug-EMT pathway. Our findings provide a strategy to eradicate HDACi-induced ESCC cells migration by targeting RelA as a combination therapy with nonspecific HDACi in ESCC treatment.
Subject(s)
Epithelial-Mesenchymal Transition/drug effects , Esophageal Neoplasms/pathology , Esophageal Squamous Cell Carcinoma/pathology , Gene Expression Regulation, Neoplastic/drug effects , Hydroxamic Acids/pharmacology , Lysine/chemistry , Transcription Factor RelA/metabolism , Acetylation , Apoptosis , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Cell Movement , Cell Proliferation , Esophageal Neoplasms/drug therapy , Esophageal Neoplasms/metabolism , Esophageal Squamous Cell Carcinoma/drug therapy , Esophageal Squamous Cell Carcinoma/metabolism , Histone Deacetylase Inhibitors/pharmacology , Humans , Transcription Factor RelA/chemistry , Transcription Factor RelA/genetics , Tumor Cells, CulturedABSTRACT
Our previous study generated a series of cybrids containing mitochondria of synaptosomes from mice at different ages. The following functional analysis on these cybrids revealed an age-dependent decline of mitochondrial function. To understand the underlying mechanisms that contribute to the age-related mitochondrial dysfunction, we focused on three cybrids carrying mitochondria derived from synaptosomes of the old mice that exhibited severe respiratory deficiencies. In particular, we started with a comprehensive analysis of mitochondrial genome by high resolution, high sensitive deep sequencing method. Compared with young control, we detected a significant accumulation of heteroplasmic mtDNA mutations. These mutations included six alterations in main control region that has been shown to regulate overall gene-expression, and four alterations in protein coding region, two of which led to significant changes in complex I subunit ND5 and complex III subunit CytB. Interestingly, a reduced mtDNA-encoded protein synthesis was associated with the changes in the main control region. Likewise, mutations in ND5 and CytB were associated with defects in assembly of respiratory complexes. Altogether, the identified age-dependent accumulation of mtDNA mutations in mouse brain likely contributes to the decline in mitochondrial function.
Subject(s)
Aging/genetics , DNA, Mitochondrial/genetics , Mitochondrial Diseases/genetics , Mutation , Oxidative Phosphorylation , Aging/metabolism , Animals , DNA, Mitochondrial/metabolism , Electron Transport Complex I/genetics , Electron Transport Complex I/metabolism , Electron Transport Complex III/genetics , Electron Transport Complex III/metabolism , Humans , Mice , Mitochondrial Diseases/metabolism , RatsABSTRACT
MitoNEET is the first identified iron sulfur protein that located in the mitochondrial outer membrane. We showed that knockdown of mitoNEET did not affect the iron sulfur protein expression in mitochondria and cytoplasm, but significantly reduced the cytosolic aconitase activity. The reduction of aconitase activity was rescued by transfection of wild type mitoNEET, but not by mitoNEET mutants H87C and H87S. Our results confirm the observation that mitoNEET is important in transferring the iron sulfur clusters to the cytosolic aconitase in living cells and the His-87 ligand in mitoNEET plays important role in this process.
Subject(s)
Aconitate Hydratase/metabolism , Cytosol/metabolism , Histidine/metabolism , Iron-Sulfur Proteins/metabolism , Mitochondria/metabolism , Mitochondrial Proteins/metabolism , Binding Sites , Biological Transport, Active/physiology , Hep G2 Cells , Histidine/chemistry , Humans , MCF-7 Cells , Mitochondrial Proteins/chemistry , Protein BindingABSTRACT
A highly sensitive magnetic field sensor based on a fiber ring laser has been proposed and experimentally demonstrated. The magnetic field sensor was fabricated by introducing a rotary apparatus modulated by an external magnetic field into the fiber cavity to twist one section of the fiber. Due to the remarkable birefringence change induced into the laser cavity, the beat frequency generated between two polarizations of the laser is sensitive to the variation of applied magnetic field intensity. Experimental results show that the polarization mode beat frequency linearly shifts with the increment of the magnetic field intensity and the sensitivity reaches up to 7.09 KHz/Oe in the range of 0 - 437 Oe. Therefore, it will be a promising candidate for the weak magnetic field applications including military, hazard forecast and biomedical fields.
ABSTRACT
An ultra-compact optical fiber magnetic field sensor based on a microstructured optical fiber (MOF) modal interference and ferrofluid (FF) has been proposed and experimentally demonstrated. The magnetic field sensor was fabricated by splicing a tapered germanium-doped index guided MOF with six big holes injected with FF to two conventional single-mode fibers. The transmission spectra of the proposed sensor under different magnetic field intensities have been measured and theoretically analyzed. Due to an efficient interaction between the magnetic nanoparticles in FF and the excited cladding mode, the magnetic field sensitivity reaches up to117.9pm/mT with a linear range from 0mT to 30mT. Moreover, the fabrication process of the proposed sensor is simple, easy and cost-effective. Therefore, it will be a promising candidate for military, aviation industry, and biomedical applications, especially, for the applications where the space is limited.
ABSTRACT
Lappulaeffusa D.H.Liu & W.J.Li, a new species of Boraginaceae from Xinjiang, China, is described and illustrated in this study. The new species is morphologically similar to Lappulahimalayensis and L.tadshikorum. However, it can be distinguished from the compared species by several characteristics, such as: stem single, erect, frequently branched at middle and above, densely spreading hispid, hairs discoid at base; corolla white or blue; fruit compressed, heteromorphic nutlets with two rows of marginal glochids, nutlets acute ovoid, disc narrowly ovate-triangular. The diagnosis of the new species is supported with comprehensive investigation including photographs, detailed description, notes on etymology, distribution and habitat, conservation status, as well as comparisons with morphologically similar species.
ABSTRACT
The HAP clade, mainly including Helichrysum Mill, Anaphalis DC., and Pseudognaphalium Kirp., is a major component of tribe Gnaphalieae (Asteraceae). In this clade, Anaphalis represents the largest genus of Asian Gnaphalieae. The intergeneric relationships among Anaphalis and its related genera and the infrageneric taxonomy of this genus are complex and remain controversial. However, there are few studies that have focused on these issues. Herein, based on the current most comprehensive sampling of the HAP clade, especially Anaphalis, we conducted phylogenetic analyses using chloroplast (cp) genome and nuclear ribosomal DNA (nrDNA) to evaluate the relationships within HAP clade, test the monophyly of Anaphalis, and examine the infrageneric taxonomy of this genus. Meanwhile, the morphological characters were verified to determine the circumscription and infrageneric taxonomy system of Anaphalis. Additionally, the biogeographical history, diversification processes, and evolution of crucial morphological characters were estimated and inferred. Our phylogenetic analyses suggested that Anaphalis is polyphyletic because it nested with Helichrysum and Pseudognaphalium. Two and four main clades of Anaphalis were identified in cp genome and nrDNA trees, respectively. Compared with nrDNA trees, the cp genome trees were more effective for phylogenetic resolution. After comprehensively analyzing morphological and phylogenetic evidence, it was concluded that the achene surface ornamentation and leaf base showed less homoplasy and supported the two Anaphalis lineages that were inferred from cp genome. Our biogeographical analyses based on cp genome indicated that HAP clade underwent rapid diversification from late Miocene to Pliocene. The two Anaphalis lineages appeared to have originated in Africa, then spread to Western and Southern Asia, and subsequently moved into Southwestern China forming a diversity center. The dispersal patterns of the two Anaphalis lineages were different. One dispersed around the world, except in Africa and South America. The other one dispersed to Eastern and Southeastern Asia from the ancestral origin region.
ABSTRACT
OBJECTIVE: To study the relationship between CD4 + CD25 + Foxp3 + regulatory T cells and Th17 responses during pulmonary infection of Chlamydia muridarum (Cm) in BALB/c mice. [Methods] BALB/c mice aged 6-8 weeks were inoculated intranasally with 5 x 103 IFU of Cm to set up the murine model of Chlamydial pneumonia. The boet weight changes, the growth of Cm and the pathology in the lung were monitored at different time post-infection. In determine the CD4 + CD25 + Foxp3 + regulatory T cells responses in BALB/c mice, intracellular cytokine staining was used to assay the percentage of CD4 + CD25 + Foxp3 + T cells in the spleen and mediastinum lymph node (MLN). The production of cytokines/chemokines in the lung were monitored, including IL-6,TGF-beta,IL-17 ,IL-2 (by ELISA), K(C and MIP-2 (by RT-PCR). RESULTS: Intranasally infected with 5 x 10(3) IFU of Cm in mice resulted in chlamydial pneumonitis featured by body weight lost, chlamydia growth and pathological damage in the lung compared with their uninfected counterparts. On day 3 post-infection, the percentage of CD4 + CD25 + Foxp3 + T cells in the spleen and MLN were significantly decreased than the control mice; then began to increase and recover to the original level on day 7 post-infection. The production of Th17 associated cytokines/chemokines such as IL-6, IL-17, KCand MIP-2 increased, which peaked on day 7 post-infection, then gradually reduced. The production of TGF-beta and IL-2 was consistent with the trend of CD4 + CD25 + Foxp3 + T cells. CONCLUSION: During pulmonary infection of Cm in BALB/c mice, CD4 + CD25 + Foxp3 + regulatory T cells may promote type 17 T cell immunity through providing TGF-beta in the presence of IL-6.
Subject(s)
Chlamydia Infections/immunology , Chlamydia muridarum/physiology , Lung Diseases/immunology , T-Lymphocytes, Regulatory/immunology , Th17 Cells/immunology , Animals , Chlamydia Infections/microbiology , Female , Humans , Interleukin-2/immunology , Interleukin-6/immunology , Lung Diseases/microbiology , Mice , Mice, Inbred BALB CABSTRACT
The genus Trigonotis comprises nearly 60 species mainly distributed in East and Southeast Asia. China has the largest number of Trigonotis species in the world, with a total of 44 species, of which 38 are endemic. Nutlet morphology is useful for the taxonomic delimitation of Trigonotis. However, there are still controversial circumscriptions of nutlet shape in some species. In previous studies, interspecies phylogenetic relationships were inferred using few DNA markers and very few taxa, which possibly led to erroneous or incomplete conclusions. In this study, the nutlet morphology of 39 Trigonotis taxa and the characteristics of 34 complete chloroplast genomes (29 taxa) were investigated and analyzed. Then, the phylogenetic relationships were discussed within this genus based on complete chloroplast genomes. To the best of our knowledge, this study is the first comprehensive analysis of nutlet morphology and complete chloroplast genome of Trigonotis. Based on nutlet morphology, Trigonotis can be divided into two groups: Group 1, hemispherical or oblique tetrahedron with carpopodiums, and Group 2, inverted tetrahedron without carpopodiums. The chloroplast genome of Trigonotis exhibited a typical quadripartite structure, including 84-86 protein-coding, 37 transfer RNA, and 8 ribosomal RNA genes, with a total length of 147,247-148,986 bp. Genes in the junctions were well conserved in Trigonotis, similar to those in other Boraginaceae s.str. species. Furthermore, Trigonotis chloroplast genomes showed relatively high diversity, with more conserved genic regions than intergenic regions; in addition, we detected 14 hot spots (Pi > 0.005) in non-coding regions. Phylogenetic analyses based on chloroplast genome data identified highly resolved relationships between Trigonotis species. Specifically, Trigonotis was divided into two clades with strong support: one clade included species with hemispherical or oblique tetrahedron nutlets with carpopodiums and bracts, whereas the other clade included species with inverted tetrahedron nutlets without carpopodiums or bracts. Our results may inform future taxonomic, phylogenetic, and evolutionary studies on Boraginaceae.
ABSTRACT
Mitochondria are the only organelles in animal cells which possess their own genomes. Mitochondrial DNA (mtDNA) alterations have been associated with various human conditions. Yet, their role in pathogenesis remains largely unclear. This review focuses on several major features of mtDNA: (1) mtDNA haplogroup, (2) mtDNA common deletion, (3) mtDNA mutations in the control region or D-loop, (4) mtDNA copy number alterations, (5) mtDNA mutations in translational machinery, (6) mtDNA mutations in protein coding genes (7) mtDNA heteroplasmy. We will also discuss their implications in various human diseases.
Subject(s)
DNA, Mitochondrial/physiology , DNA, Mitochondrial/genetics , Humans , MutationABSTRACT
Inflammation, when properly mounted and precisely calibrated, is a beneficial process that enables the rapid removal of invading pathogens and/or cellular corpses and promotes tissue repair/regeneration to restore homeostasis after injury. Being a paradigm of a rapid response transcription factor, the nuclear factor-kappa B (NF-κB) transcription factor family plays a central role in amplifying inflammation by inducing the expression of inflammatory cytokines and chemokines. Additionally, NF-κB also induces the expression of pro-survival and -proliferative genes responsible for promoting tissue repair and regeneration. Paradoxically, recent studies have suggested that the NF-κB pathway can also exert inhibitory effects on pro-inflammatory cytokine production to temper inflammation. Here, we review our current understanding about the pro- and anti-inflammatory roles of NF-κB and discuss the implication of its dichotomous inflammation-modulating activity in the context of inflammasome activation and tumorigenesis.
ABSTRACT
Lappulasinaica was recently transferred to the monotypic genus Pseudolappula based on phylogenetic studies, while the related species, L.occultata, has remained in the genus Lappula. In this study, morphological, molecular, and palynological evidence supports that L.occultata should be transferred to the genus Pseudolappula. Both L.occultata and P.sinaica share a combination of nutlets features that distinguish them from Lappula: a longer adaxial keel and a linear attachment scar. Phylogenetic analysis based on ITS and trnL-F strongly supports L.occultata as the sister taxon of P.sinaica. In addition, pollen grains of these two species are 3-syncolporate with 3 alternating pseudocolpi, which is significantly different from the grains of Lappula taxa. Based on the above evidence, the new combination Pseudolappulaoccultata is proposed.
ABSTRACT
BACKGROUND: Histone deacetylases (HDACs) have been demonstrated to be aberrantly activated in tumorigenesis and cancer development. Thus, HDAC inhibitors (HDACIs) are considered to be promising anti-cancer therapeutics. However, recent studies have shown that HDACIs promote the migration of many cancer cells. Therefore, there is a need to elucidate the underlying mechanisms of HDACIs on cancer cell migration to establish a combination therapy that overcomes HDACI-induced cell migration. METHODS: KYSE-150 and EC9706 cells were treated differently. Effects of drugs and siRNA treatment on tumor cell migration and cell signaling pathways were investigated by transwell migration assy. Gene expression for SNAI2 was tested by RT-qPCR. Western blot analysis was employed to detect the level of E-cadherin, ß-catenin, vimentin,Slugï¼ERK1/2, H3, PAI-1 and BRD4. The effect of drugs on cell morphology was evaluated through phase-contrast microscopic images. RESULTS: TSA promotes epithelial-mesenchymal transition (EMT) in ESCC cells by downregulating the epithelial marker E-cadherin and upregulating mesenchymal markers ß-catenin, vimentin, Slug, and PAI-1. Knockdown of Slug by siRNA or inhibition of PAI-1 clearly suppressed TSA-induced ESCC cell migration and resulted in the reversal of TSA-triggered E-cadherin, ß-catenin, and vimentin expression. However, no crosstalk between Slug and PAI-1 was observed in TSA-treated ESCC cells. Blocking ERK1/2 activation also inhibited TSA-induced ESCC cell migration, EMT, and upregulation of Slug and PAI-1 levels in ESCC cells. Interestingly, inhibition of BRD4 suppressed TSA-induced ESCC cell migration and attenuated TSA-induced ERK1/2 activation and upregulation of Slug and PAI-1 levels. CONCLUSIONS: Our data indicate the existence of at least two separable ERK1/2-dependent signaling pathways in TSA-mediated ESCC cell migration: an ERK1/2-Slug branch and an ERK1/2-PAI-1 branch. Both branches of TSA-induced ESCC cell migration appear to favor the EMT process, while BRD4 is responsible for two separable ERK1/2-dependent signaling pathways in TSA-mediated ESCC cell migration.
Subject(s)
Cell Cycle Proteins/metabolism , Epithelial-Mesenchymal Transition/drug effects , Esophageal Neoplasms , Esophageal Squamous Cell Carcinoma , Hydroxamic Acids/pharmacology , MAP Kinase Signaling System/physiology , Transcription Factors/metabolism , Butadienes/pharmacology , Cadherins/metabolism , Cell Line, Tumor , Cell Movement/drug effects , Cell Movement/physiology , Cell Shape/drug effects , Esophageal Neoplasms/drug therapy , Esophageal Neoplasms/metabolism , Esophageal Neoplasms/pathology , Esophageal Squamous Cell Carcinoma/drug therapy , Esophageal Squamous Cell Carcinoma/metabolism , Esophageal Squamous Cell Carcinoma/pathology , Flavonoids/pharmacology , Gene Expression , Histone Deacetylase Inhibitors/pharmacology , Histone Deacetylases/physiology , Humans , Hydroxamic Acids/metabolism , MAP Kinase Signaling System/drug effects , Nitriles/pharmacology , Plasminogen Activator Inhibitor 1/metabolism , Protein Kinase Inhibitors/pharmacology , RNA, Small Interfering , Snail Family Transcription Factors/genetics , Snail Family Transcription Factors/metabolism , Vimentin/metabolism , beta Catenin/metabolismABSTRACT
Innate immunity plays a prominent role in the host defense against pathogens and must be precisely regulated. As vital orchestrators in cholesterol homeostasis, microRNA-33/33* have been widely investigated in cellular metabolism. However, their role in antiviral innate immunity is largely unknown. Here, we report that VSV stimulation decreased the expression of miR-33/33* through an IFNAR-dependent manner in macrophages. Overexpression of miR-33/33* resulted in impaired RIG-I signaling, enhancing viral load and lethality whereas attenuating type I interferon production both in vitro and in vivo. In addition, miR-33/33* specifically prevented the mitochondrial adaptor mitochondrial antiviral-signaling protein (MAVS) from forming activated aggregates by targeting adenosine monophosphate activated protein kinase (AMPK), subsequently impeding the mitophagy-mediated elimination of damaged mitochondria and disturbing mitochondrial homeostasis which is indispensable for efficient MAVS activation. Our findings establish miR-33/33* as negative modulators of the RNA virus-triggered innate immune response and identify a previously unknown regulatory mechanism linking mitochondrial homeostasis with antiviral signaling pathways.
Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Adenylate Kinase/metabolism , Immunity, Innate , MicroRNAs/metabolism , Vesiculovirus/immunology , Animals , Antagomirs/pharmacology , Base Sequence , DEAD Box Protein 58/metabolism , Down-Regulation/drug effects , Gene Silencing/drug effects , HEK293 Cells , HeLa Cells , Humans , Immunity, Innate/drug effects , Interferon Type I/metabolism , Macrophages/drug effects , Macrophages/pathology , Macrophages/virology , Mice, Inbred C57BL , MicroRNAs/genetics , Mitophagy/drug effects , Models, Biological , Protein Aggregates/drug effects , Receptor, Interferon alpha-beta/metabolism , Receptors, Immunologic/metabolism , Signal Transduction/drug effectsABSTRACT
FBXW7 functions as an E3 ubiquitin ligase to mediate oncoprotein degradation via the ubiquitin-proteasome system in cancer cells, effectively inhibiting the growth and survival of tumor cells. However, little is known about the functions of FBXW7 in macrophages and the tumor immune microenvironment. In this study, we find that FBXW7 suppresses M2-like tumor-associated macrophage (TAM) polarization to limit tumor progression. We identified a significant increase in the proportion of M2-like TAMs and aggravated tumor growth in mice with myeloid FBXW7 deficiency by subcutaneous inoculation with Lewis lung carcinoma cells (LLCs). When stimulated with LLCs supernatant in vitro, FBXW7-knockout macrophages displayed increased M2 macrophage polarization and enhanced ability of supporting cancer cells growth. In mechanism, we confirmed that FBXW7 inhibited M2-like TAM polarization by mediating c-Myc degradation via the ubiquitin-proteasome system. These findings highlight the role of FBXW7 in M2-like TAM polarization and provide new insights into the potential targets for cancer immunotherapies.
Subject(s)
Carcinoma, Lewis Lung/enzymology , F-Box-WD Repeat-Containing Protein 7/metabolism , Proto-Oncogene Proteins c-myc/metabolism , Tumor-Associated Macrophages/enzymology , Animals , Carcinoma, Lewis Lung/genetics , Carcinoma, Lewis Lung/pathology , Cell Proliferation , Cells, Cultured , F-Box-WD Repeat-Containing Protein 7/deficiency , F-Box-WD Repeat-Containing Protein 7/genetics , Gene Expression Regulation, Neoplastic , Mice, Inbred C57BL , Mice, Knockout , Phenotype , Proteasome Endopeptidase Complex/metabolism , Proteolysis , Proto-Oncogene Proteins c-myc/genetics , Signal Transduction , Tumor Burden , Tumor Microenvironment , Tumor-Associated Macrophages/pathology , UbiquitinationABSTRACT
OBJECTIVES: Mitofilin contributes to the maintenance of mitochondrial structure and functions. This study was undertaken to determine the mechanisms underlying its regulation of apoptosis. MATERIALS AND METHODS: Mitofilin was knockdowned by specific short hairpin RNA (shRNA) and the stable HeLa cell clone was selected. The autophagy activity were assessed with LC3-II conversion and puncta formation by western blot and fluorescence imaging in starved and normal cultured HeLa cells. Autophagy flux was measured in the presence of NH4Cl. Wortmannin was used to inhibit autophagy. Cell viability and apoptosis were detected with cell counting kit-8 (CCK-8) and fluorescence-activated cell sorting (FACS) assay, respectively. RESULTS: Mitofilin expression was down-regulated in starved HeLa cells. In established mitofilin stable knockdown cell lines, LC3-II conversion and puncta formation were detected, which are both hallmarks of autophagy, under both basal and starvation conditions. Mitofilin down-regulation decreased LC3-II conversion and puncta formation, which indicates that loss of mitofilin function inhibits both basal and starvation-induced autophagy activity. CCK-8 and FACS analysis confirmed mitofilin involvement in the regulation of cell survival since mitofilin down-regulation facilitated starvation-induced apoptosis in HeLa cells. CONCLUSION: Taken together, mitofilin is a potent regulator of autophagy and it may modulate cell survival through regulation of autophagy.
ABSTRACT
PURPOSE: Cancer-testis (CT) antigens are often expressed in a proportion of tumors of various types. Their restricted normal tissue expression and immunogenicity make them potential targets for immunotherapy. CABYR is a calcium-binding tyrosine phosphorylation-regulated fibrous sheath protein initially reported to be testis specific and subsequently shown to be present in brain tumors. This study was to determine whether CABYR is a novel CT antigen in lung cancer. EXPERIMENTAL DESIGN: mRNA expression of CABYR-a/b (combination of CABYR-a and CABYR-b) and CABYR-c was examined in 36 lung cancer specimens, 14 cancer cell lines, and 1 normal cell line by conventional and real-time reverse transcription-PCR. Protein expression of CABYR was analyzed in 50 lung cancer tissues by immunohistochemistry. Antibodies specific to CABYR were analyzed in sera from 174 lung cancer patients and 60 healthy donors by ELISA and Western blot. RESULTS: mRNA expression of CABYR-a/b and CABYR-c was observed, respectively, in 13 and 15 of 36 lung cancer tissues as well as in 3 and 5 of 14 cancer cell lines, whereas neither of them was observed in adjacent noncancerous tissues or the normal cell line. Protein expression of CABYR-a/b and CABYR-c was observed, respectively, in 20 and 19 of 50 lung cancer tissues. IgG antibodies specific to CABYR-a/b and CABYR-c were detected, respectively, in 11% and 9% of sera from lung cancer patients but not from the 60 healthy donors. CONCLUSION: CABYR is a novel CT antigen in lung cancer and may be a promising target for immunotherapy for lung cancer patients.
Subject(s)
Antigens, Neoplasm/biosynthesis , Calcium-Binding Proteins/biosynthesis , Lung Neoplasms/immunology , Phosphoproteins/biosynthesis , Antibodies, Neoplasm/blood , Antibodies, Neoplasm/immunology , Antibody Specificity , Antigens, Neoplasm/blood , Antigens, Neoplasm/genetics , Antigens, Neoplasm/immunology , Calcium-Binding Proteins/blood , Calcium-Binding Proteins/genetics , Calcium-Binding Proteins/immunology , Cell Line, Tumor , HeLa Cells , Humans , Immunohistochemistry , K562 Cells , Lung Neoplasms/blood , Lung Neoplasms/genetics , Male , Phosphoproteins/blood , Phosphoproteins/genetics , Phosphoproteins/immunology , Protein Isoforms , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , Testis/immunologyABSTRACT
OBJECTIVE: To identify serum diagnosis or progression biomarkers in patients with lung cancer using protein chip profiling analysis. METHOD: Profiling analysis was performed on 450 sera collected from 213 patients with lung cancer, 19 with pneumonia, 16 with pulmonary tuberculosis, 65 with laryngeal carcinoma, 55 with laryngopharyngeal carcinoma patients, and 82 normal individuals. A new strategy was developed to identify the biomarkers on chip by trypsin pre-digestion. RESULTS: Profiling analysis demonstrated that an 11.6 kDa protein was significantly elevated in lung cancer patients, compared with the control groups (P < 0.001). The level and percentage of 11.6 kDa protein progressively increased with the clinical stages I-IV and were also higher in patients with squamous cell carcinoma than in other subtypes. This biomarker could be decreased after operation or chemotherapy. On the other hand, 11.6 kDa protein was also increased in 50% benign diseases of lung and 13% of other cancer controls. After trypsin pre-digestion, a set of new peptide biomarkers was noticed to appear only in the samples containing a 11.6 kDa peak. Further identification showed that 2177 Da was a fragment of serum amyloid A (SAA, MW 11.6 kDa). Two of the new peaks, 1550 Da and 1611 Da, were defined from the same protein by database searching. This result was further confirmed by partial purification of 11.6 kDa protein and MS analysis. CONCLUSION: SAA is a useful biomarker to monitor the progression of lung cancer and can directly identify some biomarkers on chip.
Subject(s)
Biomarkers, Tumor/blood , Lung Neoplasms/blood , Serum Amyloid A Protein/analysis , Adenocarcinoma/blood , Adenocarcinoma/pathology , Adult , Aged , Carcinoma, Small Cell/blood , Carcinoma, Small Cell/pathology , Carcinoma, Squamous Cell/blood , Carcinoma, Squamous Cell/pathology , Female , Humans , Lung Neoplasms/pathology , Male , Middle Aged , Neoplasm Staging , Peptides/blood , Protein Array AnalysisABSTRACT
Lung cancer is at present the number one cause of cancer death and no biomarker is available to detect early lung cancer in serum samples so far. The objective of this study is to find specific biomarkers for detection of lung cancer using Surface Enhanced Laser Desorption/Ionization (SELDI) technology. In this study, serum samples from 30 lung cancer patients and 51 age-and sex-matched healthy were analyzed by SELDI based ProteinChip reader, PBSII-C. The spectra were generated on WCX2 chips and protein peaks clustering and classification analyses were performed utilizing Biomarker Wizard and Biomarker Patterns software packages, respectively. Three protein peaks were automatically chosen for the system training and the development of a decision classification tree. The constructed model was then used to test an independent set of masked serum samples from 15 lung cancer patients and 31 healthy individuals. The analysis yielded a sensitivity of 93.3%, and a specificity of 96.7%. These results suggest that the serum is a capable resource for detection of specific lung cancer biomarkers. SELDI technique combined with an artificial intelligence classification algorithm can both facilitate the discovery of better biomarkers for lung cancer and provide a useful tool for molecular diagnosis in future.