Annexin A1 Protein Expression Research Articles

Differential Expression of Annexin A1 Protein in Colorectal, Lung, and Liver Cancer Tissues

Differential Expression of Annexin A1 Protein in Colorectal, Lung, and Liver Cancer Tissues

Abstract P3082: Loss Of Myeloid Cell-specific Beta2-adrenergic Receptor Improves Cardiac Function After Acute Ischemia

Heart failure (HF) is one of the leading causes of global mortality, which is often caused by acute myocardial infarction (MI). This type of acute cardiac injury promotes robust inflammatory cascades by regulating spatiotemporal myeloid cell (neutrophil, monocyte and macrophage) responses in the infarct area, which are essential in the orchestration of post-infarct tissue remodeling and repair. We previously reported that deletion of β2-adrenergic receptor (β2AR) in all cells of hematopoietic origin resulted in generalized disruption of immune cell responsiveness to injury, but with unknown impact of myeloid cells in particular. To investigate this, we crossed floxed β2AR (β2 f/f ) mice with myeloid cell-expressing Cre (LysM-Cre) mice to generate myeloid cell-specific β2AR knockout mice (LB2) and subjected them to MI. M-mode echocardiography indicated a preservation of ejection fraction (%EF) and fractional shortening (%FS) in the LB2 mice versus either β2 f/f or LysM-Cre mice at 3 days post-MI, which was maintained at 28 days post-MI, concurrent with reduced infarct size and interstitial fibrosis, suggesting a cardioprotective role of myeloid cell-specific β2-AR deletion. While immune cell profiling by FACS analysis showed similar CD45 + CD11b + Ly6C + monocyte, CD45 + CD11b + Ly6G + neutrophil and CD45 + CD11b + F4/80 + macrophage accumulation in LB2 and β2 f/f mouse hearts at 1 day post-MI, neutrophil frequency was significantly reduced in LB2 mouse hearts by 4 days post-MI, suggesting LB2 hearts have enhanced capacity for efferocytosis of dead cells. Notably, RT-qPCR analysis revealed a significant upregulation of pro-efferocytosis genes in LB2 bone marrow cells, including annexin A1 (ANXA1). Additionally, ANXA1 protein expression was shown to be upregulated in LB2 versus β2 f/f cardiac CD11b + myeloid cells, including macrophages, at 1-day post-MI. In vitro efferocytosis assay data suggested that there was significant increment in %-efferocytosis of LB2 neutrophils as compared to β2 f/f . Taken together, our data suggest that β2AR is a crucial regulator of myeloid cell-dependent efferocytosis in the heart following injury and suggests a crucial timepoint at which β2AR-selective therapeutics may promote the clearance of dead cells to promote repair.

A meta-analysis of genome-wide association studies of childhood wheezing phenotypes identifies ANXA1 as a susceptibility locus for persistent wheezing.

Many genes associated with asthma explain only a fraction of its heritability. Most genome-wide association studies (GWASs) used a broad definition of 'doctor-diagnosed asthma', thereby diluting genetic signals by not considering asthma heterogeneity. The objective of our study was to identify genetic associates of childhood wheezing phenotypes. We conducted a novel multivariate GWAS meta-analysis of wheezing phenotypes jointly derived using unbiased analysis of data collected from birth to 18 years in 9568 individuals from five UK birth cohorts. Forty-four independent SNPs were associated with early-onset persistent, 25 with pre-school remitting, 33 with mid-childhood remitting, and 32 with late-onset wheeze. We identified a novel locus on chr9q21.13 (close to annexin 1 [ANXA1], p<6.7 × 10-9), associated exclusively with early-onset persistent wheeze. We identified rs75260654 as the most likely causative single nucleotide polymorphism (SNP) using Promoter Capture Hi-C loops, and then showed that the risk allele (T) confers a reduction in ANXA1 expression. Finally, in a murine model of house dust mite (HDM)-induced allergic airway disease, we demonstrated that anxa1 protein expression increased and anxa1 mRNA was significantly induced in lung tissue following HDM exposure. Using anxa1-/- deficient mice, we showed that loss of anxa1 results in heightened airway hyperreactivity and Th2 inflammation upon allergen challenge. Targeting this pathway in persistent disease may represent an exciting therapeutic prospect. UK Medical Research Council Programme Grant MR/S025340/1 and the Wellcome Trust Strategic Award (108818/15/Z) provided most of the funding for this study.

In-depth quantitative proteomics analysis revealed C1GALT1 depletion in ECC-1 cells mimics an aggressive endometrial cancer phenotype observed in cancer patients with low C1GALT1 expression

BackgroundEndometrial cancer (EC) is the most common cancer of the female reproductive organs. Despite the good overall prognosis of most low-grade ECs, FIGO I and FIGO II patients might experience tumor recurrence and worse prognosis. The study of alterations related to EC pathogenesis might help to get insights into underlying mechanisms involved in EC development and progression.MethodsCore tumoral samples were used to investigate the role of C1GALT1 in EC by immunohistochemistry (IHC). ECC-1 cells were used as endometrioid EC model to investigate the effect of C1GALT1 depletion using C1GALT1 specific shRNAs. SILAC quantitative proteomics analyses and cell-based assays, PCR, qPCR, WB, dot-blot and IHC analyses were used to identify, quantify and validate dysregulation of proteins.ResultsLow C1GALT1 protein expression levels associate to a more aggressive phenotype of EC. Out of 5208 proteins identified and quantified by LC-MS/MS, 100 proteins showed dysregulation (log2fold-change ≥ 0.58 or ≤-0.58) in the cell protein extracts and 144 in the secretome of C1GALT1 depleted ECC-1 cells. Nine dysregulated proteins were validated. Bioinformatics analyses pointed out to an increase in pathways associated with an aggressive phenotype. This finding was corroborated by loss-of-function cell-based assays demonstrating higher proliferation, invasion, migration, colony formation and angiogenesis capacity in C1GALT1 depleted cells. These effects were associated to the overexpression of ANXA1, as demonstrated by ANXA1 transient silencing cell-based assays, and thus, correlating C1GALT and ANXA1 protein expression and biological effects. Finally, the negative protein expression correlation found by proteomics between C1GALT1 and LGALS3 was confirmed by IHC.ConclusionC1GALT1 stably depleted ECC-1 cells mimic an EC aggressive phenotype observed in patients and might be useful for the identification and validation of EC markers of progression.

SUPPLEMENTARY TABLES AND FIGURES: Bioinformatic analysis of Annexin A1 (ANXA1) protein expression in different types of cancer.

SUPPLEMENTARY TABLES AND FIGURES: Bioinformatic analysis of Annexin A1 (ANXA1) protein expression in different types of cancer.

Effects of hyperosmolarity on annexin A1 on ocular surface epithelium in vitro

Osmotic stress is an important challenge to cell function. Dry eye pathology is characterized by elevated tear film osmolarity as consequence of decreased tear secretion and/or increased evaporation. Dry eye pathogenesis is not completely clarified. However, it is known that tear hyperosmolarity induces NLRP3 (nucleotide-binding oligomerization domain-like receptor family, pyrin domain-cointaining 3) inflammasome activation and inflammatory mediators release that leads to ocular surface damage.Annexin A1 is a protein involved in anti-inflammatory or pro-resolution actions in different tissues while its presence and biological role on ocular surface has been scarcely examined. In this study, potential changes in annexin A1 protein expression and secretion on the ocular surface after exposure to hyperosmolar conditions were evaluated. In addition, considering the significant role of inflammation in dry eye pathology, the potential anti-inflammatory activity of Ac2-26, an annexin A1 peptide mimicking its N-terminus, was assessed.Cytosolic and membrane staining was detected for annexin A1 in corneal and conjunctival epithelial cells. A native form of annexin A1 together with a truncated form were detected by western blot analysis. Under hyperosmotic conditions increased protein levels of intracellular and secreted annexin A1 as well as higher expression of its receptor Fpr2 (formyl peptide receptor type 2) were found. Treatment with mimetic peptide Ac2-26 ameliorated NLRP3 activation and interleukin 1β (IL-1β) release triggered by elevated osmolarity in corneal and conjunctival epithelial cells. These findings suggest a potential role of annexin A1 and its mimetic peptide modulating key inflammatory events associated to dry eye.

Comparative Analysis of Annexin A1 (ANXA1) Protein Expression in Different Cancer Types

Annexin A1 (ANXA1) is the first member of the Lipocortin family, a calcium‐dependent phospholipid‐binding protein with potent immunomodulatory activity. ANXA1 is related to cellular proliferation, apoptosis, progression, and metastasis in cancer, and its expression is variable depending on the tumor type. Our research will compare the expression of ANXA1 in various forms of cancer and establish if the protein is up‐or down‐regulated.MethodsWe analyzed 1904 immunohistochemistry datasets from The Human Protein Atlas (HPA). The samples represent 20 different forms of cancer from 455 patients. The expression of ANXA1 was compared to the same in tissue samples from 137 healthy subjects, which meant the tissues of origins of primary tumors. The levels of ANXA1 expression were quantified using a visual grading method based on staining intensity (I) and cell fraction stained (F). The Q score (combination of stained cell fraction and staining intensity) was obtained by the product of (F)*(I).Results9 of 20 cancer types showed increased protein expression (up‐regulation) comparison to their healthy counterparts. Eight cancer types showed decreased protein expression (down‐regulation). Three types of cancer showed no significant differences.ConclusionANXA1 expression may serve as an important diagnostic marker for such a variety of different cancer types.

Supplementary data: Comparative analysis of Annexin A1 (ANXA1) protein expression in 20 different types of cancer.

Supplementary data: Comparative analysis of Annexin A1 (ANXA1) protein expression in 20 different types of cancer.

Supplementary data: Comparative analysis of Annexin A1 (ANXA1) protein expression in 20 different types of cancer.

Supplementary data: Comparative analysis of Annexin A1 (ANXA1) protein expression in 20 different types of cancer.

Maintenance of cellular annexin A1 level is essential for PI3K/AKT/mTOR-mediated proliferation of pancreatic beta cells.

Annexin A1 (AnxA1, also known as lipocortin-1), is a calcium-dependent phospholipid binding protein with diverse functions. Previous studies have indicated that AnxA1 is associated with age-related β-cell dysfunction and aging, which lead to decreased β-cell proliferation capacity. However, it has been uncertain whether AnxA1 affects the proliferation of pancreatic beta (β) cells. In the present study, we reduced AnxA1 expression in the MIN6 islet β-cell line using small interfering RNA (AnxA1-siRNA), then measured cell cycle distribution and cellular proliferation. We also measured the expression levels of cell cycle-related proteins such as cyclin D1, cyclin E, and cyclin-dependent kinase 2 (CDK2) by Western blot analysis. We investigated the phosphatidylinositol 3-kinase (PI3K)/ serine/threonine protein kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling pathway to explore the potential mechanism underlying the observed effects. Knockdown of AnxA1 expression using siRNA reduced the rates of MIN6 cell proliferation. The proportions of cells in S and G2/M phases also decreased upon inhibition of AnxA1. Moreover, AnxA1 protein expression in MIN6 cells was positively related to the protein levels of cyclin D1, cyclin E, and CDK2. Activation of the PI3K/Akt/mTOR signaling pathway by AnxA1 may be involved in the signaling cascade to regulate cell proliferation. This study identified a positive correlation between AnxA1 protein and pancreatic β-cell proliferation. AnxA1 protein expression might affect the proliferation of MIN6 cells via regulation of cyclin D1, cyclin E, and CDK2 proteins, as well as the PI3K/Akt/mTOR signaling pathway.

Cisplatin treatment modulates Annexin A1 and inhibitor of differentiation to DNA 1 expression in cervical cancer cells

Cisplatin (Cis) is a choice chemotherapy approach to cervical cancer by inducing DNA adducts and subsequent apoptosis. We have investigated the effects of Cis on Annexin A1 (ANXA1) and inhibitor of DNA binding 1 (ID1) proteins expression to elucidate further mechanisms of Cis actions. Human cervical tissue samples from twenty-four patients, with Cervical Intraepithelial Neoplasia (CIN, stage I, II and III), were evaluated to quantified ANXA1 and ID1 expressions. In vitro, human epidermoid carcinoma of the cervix (SiHa cell line) were treated with Annexin A1 peptide (ANXA12−26), Cis or Cis + ANXA12−26 to evaluate cell proliferation and migration, cytotoxicity of treatments as well as ANXA1 and ID1 modulations by mRNA and protein expression. Our findings showed expression of ID1 and ANXA1 proteins in tissue samples from Cervical Intraepithelial Neoplasia (CIN) patients, with intense immunological identification of ID1 in the CIN III stage. In SiHa cells, treatments with Cis alone or Cis + ANXA12−26, increase mRNA expressions of the ANXA1 and reduced the ID1. In agreement, Cis + ANXA12−26 enhanced ANXA1 protein expression and Cis or Cis + ANXA12−26 abolished ID1 protein expression. Cell proliferation was reduced after treatment with ANXA12−26 peptide and more significant after Cis or Cis + ANXA12−26 treatments. These two last treatments reduced cell viability, by inducing late apoptosis, and impaired cell migration. Together, our data highlight endogenous ANXA1 is involved in Cis therapy for cervical cancer.

Upregulation of annexin A1 protein expression in the intratumoral vasculature of human non-small-cell lung carcinoma and rodent tumor models.

Annexin A1 (anxA1) is an immunomodulatory protein that has been proposed as a tumor vascular target for antitumor biologic agents, yet to date the vascular expression of anxA1 in specific tumor indications has not been systematically assessed. Attempts to evaluate vascular anxA1 expression by immunohistochemistry are complicated by a lack of available antibodies that are both specific for anxA1 and bind the N-terminal–truncated form of anxA1 that has previously been identified in tumor vasculature. To study the vascular expression pattern of anxA1 in non–small-cell lung carcinoma (NSCLC), we isolated an antibody capable of binding N-terminal–truncated anxA127-346 and employed it in immunohistochemical studies of human lung specimens. Lung tumor specimens evaluated with this antibody revealed vascular (endothelial) anxA1 expression in five of eight tumor samples studied, but no vascular anxA1 expression was observed in normal lung tissue. Tumor microarray analysis further demonstrated positive vascular staining for anxA1 in 30 of 80 NSCLC samples, and positive staining of neoplastic cells was observed in 54 of 80 samples. No correlation was observed between vascular and parenchymal anxA1 expression. Two rodent tumor models, B16-F10 and Py230, were determined to have upregulated anxA1 expression in the intratumoral vasculature. These data validate anxA1 as a potential vascular anti-tumor target in a subset of human lung tumors and identify rodent models which demonstrate anxA1 expression in tumor vasculature.

Suppression of TRPM7 Inhibited Hypoxia-Induced Migration and Invasion of Androgen-Independent Prostate Cancer Cells by Enhancing RACK1-Mediated Degradation of HIF-1α.

Transient receptor potential melastatin subfamily member 7 (TRPM7) was essential in the growth and metastatic ability of prostate cancer cells. However, the effects and the relevant molecular mechanisms of TRPM7 on metastasis of prostate cancer under hypoxic atmosphere remain unclear. This study investigated the role of TRPM7 in the metastatic ability of androgen-independent prostate cancer cells under hypoxia. First, data mining was carried out to disclose the relationship between the TRPM7 gene level and the survival of prostate cancer patients. Specific siRNAs were used to knockdown target genes. Western blotting and qPCR were employed to determine protein and gene expression, respectively. The gene transcription activity was evaluated by luciferase activity assay of promoter gene. The protein interaction was determined by coimmunoprecipitation. Wound healing and transwell assays were employed to evaluated cell migration and invasion, respectively. Open access database results showed that high expression of TRPM7 was closely related to the poor survival of prostate cancer patients. Hypoxia simultaneously increased TRPM7 expression and induced HIF-1α accumulation in androgen-independent prostate cancer cells. Knockdown of TRPM7 significantly promoted HIF-1α degradation through the proteasome and inhibited EMT changes in androgen-independent prostate cancer cells under hypoxic condition. Moreover, TRPM7 knockdown increased the phosphorylation of RACK1 and strengthened the interaction between RACK1 and HIF-1α but attenuated the binding of HSP90 to HIF-1α. Whereas knockdown of RACK1 increased the binding of HSP90 to HIF-1α. Furthermore, both TRPM7 and HIF-1α knockdown significantly suppressed hypoxia-induced Annexin A1 protein expression, and suppression of HIF-1α/Annexin A1 signaling significantly inhibited hypoxia-induced cell migration and invasion of androgen-independent prostate cancer cells. Our findings demonstrate that TRPM7 knockdown promotes HIF-1α degradation via an oxygen-independent mechanism involving increased binding of RAKC1 to HIF-1α, and TRPM7-HIF-1α-Annexin A1 signaling axis plays a crucial role in the EMT, cell migration, and invasion of androgen-independent prostate cancer cells under hypoxic conditions.

Triple-Negative Breast Cancer with High Levels of Annexin A1 Expression Is Associated with Mast Cell Infiltration, Inflammation, and Angiogenesis.

Annexin A1 (ANXA1) is a phospholipid-linked protein involved in inflammation, immune response, and mast cell reactivity. Recently, we reported that ANXA1 is associated with aggressive features of triple-negative breast cancer (TNBC); however, its clinical relevance remains controversial. We hypothesized that human TNBC with high expression of ANXA1 mRNA is associated with pro-cancerous immune cell infiltration, including mast cells, and with an aggressive phenotype. Clinical and RNA-seq data were obtained from The Cancer Genome Atlas (TCGA, n = 1079) and Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) (n = 1904). TNBC patients had significantly higher levels of ANXA1 expression compared to the other subtypes in both TCGA and METABRIC cohorts (p < 0.001). ANXA1 protein expression was assessed by immunohistochemistry in Japanese TNBC patient cohort (n = 48), where 17 cases (35.4%) had positive ANXA1 staining, and their overall survival was significantly shorter compared with negative staining group (p = 0.008). The CIBERSORT algorithm was used to calculate immune cell infiltrations. ANXA1 high tumors were associated with activated mast cells and M2 macrophages (p > 0.01), but did not show any association with tumor heterogeneity nor cytolytic activity. High expression of ANXA1 group enriched inflammation, epithelial-to-mesenchymal transition (EMT), and angiogenesis-related genes in a gene set enrichment assay in both cohorts. To our knowledge, this is the first study to demonstrate that ANXA1 is associated with infiltration of mast cells and inflammation that is associated with the aggressive phenotype of TNBC, such as EMT and angiogenesis.

Genetic polymorphism of miRNA-196a and its target gene annexin-A1 expression based on ethnicity in Pakistani female breast cancer patients.

Objective:To evaluate the association of miR-196a rs11614913 C/T genetic variation and its target gene annexin A1 mRNA expression with breast cancer risk in Pakistani female ethnicities.Methods:This case control study, conducted from March 2017 to November 2018 included 295 breast cancer patients, 295 controls of three Pakistani ethnicities and archived 100 samples of cohort group for genotyping and expression profiling. Genotyping of miR-196a (rs11614913 C/T) was done by ARMS PCR technique. Annexin-A1 (ANXA1) mRNA expression was measured with qRT-PCR and detection of protein expression of ANXA1 was done by immunohistochemistry.Results:CC homozygous genotype of miR-196a rs11614913 was present in 81.4% of cases and 73.9% controls. C/T polymorphism was found to be significantly associated with decrease risk of breast cancer (OR=0.25 (0.11- 0.58, p <0.05). Similar trend was seen with the minor T allele (OR=0.55 (0.39-0.77, p <0.05, and both dominant and recessive models (OR=0.64; p=0.02 and OR=0.26, p=0.00). In the KPK ethnic group significant decrease association with breast cancer risk was observed (OR= 0.22 (0.09-0.53, p < 0.05). Immunohistochemical staining showed loss of ANXA1 protein expression in 72 samples, and significant association was observed with pathological type p=0. 00 and triple negative receptor status p=0.03 and with genotypes of miR-196a p=0.00. Increase relative expression of 2.81± .88 by qPCR analysis of ANXA1 mRNA was noted with TT genotype.Conclusions:Our results demonstrate that miR-196a rs11614913 C/T polymorphism is associated with a decreased risk and loss of protein expression in breast cancer in the Pakistani population.

AnnexinA1 expression is correlated with malignant potential of renal cell carcinoma.

To evaluate the expression of annexinA1 protein in patients with renal cell carcinoma. AnnexinA1 expression was examined in renal cell carcinoma specimens from 27 patients, and their disease-free survival was analyzed using the log-rank test. AnnexinA1 knockdown in the human renal cell carcinoma cell line Caki-1 was carried out, and its proliferation, invasion, motility and adhesion were compared with those of control cells. In 13 out of 27 patients, annexin A1 was highly expressed in the membrane of renal cell carcinoma tumor cells, whereas in the rest of the patients, annexinA1 expression was weak or negligible in the membrane of those cells. Patients with high annexinA1 expression had significantly poorer disease-free survival than those with weak or negligible annexinA1 expression (P=0.031). In the renal cell carcinoma cell line, annexinA1 knockdown cells showed significantly decreased proliferation, invasion, motility and adhesion relative to control cells, and expressed lower relative levels of membrane-type1 matrix metalloproteinase and hypoxia-inducible factor1-alpha transcripts, showing a potential pathway regulated by annexinA1. Annexin A1 is associated with renal cell carcinoma malignant potential and could serve as a marker of poor prognosis.

PO-146 Multiple myeloma-derived exosomes carry amphiregulin and are responsible for the uncoupled bone remodelling

IntroductionAnnexins are frequently deregulated in many cancers (‘annexinopathies’). Annexin A1 (ANXA1) overexpression has been reported in gastric, pancreatic and hepatocellular carcinoma; however, it is markedly down-regulated in breast, prostate, esophageal and head and neck cancers. The contrasting patterns of ANXA1 expression in different tumours types is just one of the enigmas in deciphering the underlying regulatory mechanisms and phenotypic specificity of ANXA1. We have previously demonstrated that ANXA1 down-regulation is an early and frequent event in the development of head and neck squamous cell carcinomas (HNSCC).Material and methodsIn an attempt to identify the underlying mechanisms of reduced ANXA1 protein expression, this study investigated ANXA1 protein expression and ANXA1 mRNA levels in HNSCC tissue specimens by immunofluoresce, in situ hybridization and RT-qPCR. Subsequently, the relative levels of miR-196a and miR-196b were quantified in paired HNSCC specimens using Taqman miRNA assays and compared to ANXA1 mRNA levels. Functional studies were performed in HNSCC cells by transfection with specific pre-miR precursors, and also ANXA1 promoter activity using deletion constructs from the 5’ ANXA1 promoter region.Results and discussionResults showed a perfect concordance between the pattern of ANXA1 mRNA and protein detected by immunofluorescence in tumours, precancerous lesions and normal epithelia, reflecting that ANXA1 down-regulation occurs at transcriptional level. We also found that both miR-196a and miR-196b levels inversely correlated with ANXA1 mRNA levels in paired HNSCC tissue samples and patient-matched normal mucosa. In addition, endogenous levels of ANXA1 mRNA and protein were consistently and significantly down-regulated upon miR-196a and miR-196b over-expression in various HNSCC-derived cell lines. The direct interaction of both mature miR-196a and miR-196b was further confirmed by transfection with Anxa1 3’UTR constructs. Combined bioinformatics and functional analysis of ANXA1 promoter activity contributed to identify key regions and potential mediators of ANXA1 transcriptional control.ConclusionThese findings demonstrate that ANXA1 down-regulation in head and neck squamous cell carcinomas occurs via transcriptional control with direct involvement of miR-196a/b.

Evaluation of miRNA-196a2 and apoptosis-related target genes: ANXA1, DFFA and PDCD4 expression in gastrointestinal cancer patients: A pilot study.

Previous reports have suggested the significant association of miRNAs aberrant expression with tumor initiation, progression and metastasis in cancer, including gastrointestinal (GI) cancers. The current preliminary study aimed to evaluate the relative expression levels of miR-196a2 and three of its selected apoptosis-related targets; ANXA1, DFFA and PDCD4 in a sample of GI cancer patients. Quantitative real-time PCR for miR-196a2 and its selected mRNA targets, as well as immunohistochemical assay for annexin A1 protein expression were detected in 58 tissues with different GI cancer samples. In addition, correlation with the clinicopathological features and in silico network analysis of the selected molecular markers were analyzed. Stratified analyses by cancer site revealed elevated levels of miR-196a2 and low expression of the selected target genes. Annexin protein expression was positively correlated with its gene expression profile. In colorectal cancer, miR-196a over-expression was negatively correlated with annexin A1 protein expression (r = -0.738, p < 0.001), and both were indicators of unfavorable prognosis in terms of poor differentiation, larger tumor size, and advanced clinical stage. Taken together, aberrant expression of miR-196a2 and the selected apoptosis-related biomarkers might be involved in GI cancer development and progression and could have potential diagnostic and prognostic roles in these types of cancer; particularly colorectal cancer, provided the results experimentally validated and confirmed in larger multi-center studies.

Ac2-26, an Annexin A1 Peptide, Attenuates Ischemia-Reperfusion-Induced Acute Lung Injury.

Annexin A1 (AnxA1) is an endogenous protein that modulates anti-inflammatory processes, and its therapeutic potential has been reported in a range of inflammatory diseases. The effect of AnxA1 on ischemia-reperfusion (IR)-induced lung injury has not been examined. In this study, isolated, perfused rat lungs were subjected to IR lung injury induced by ischemia for 40 min, followed by reperfusion for 60 min. The rat lungs were randomly treated with vehicle (phosphate-buffered saline), and Ac2-26 (an active N-terminal peptide of AnxA1) with or without an N-formyl peptide receptor (FPR) antagonist N-Boc-Phe-Leu-Phe-Leu-Phe (Boc2). An in vitro study of the effects of Ac2-26 on human alveolar epithelial cells subjected to hypoxia-reoxygenation was also investigated. Administration of Ac2-26 in IR lung injury produced a significant attenuation of lung edema, pro-inflammatory cytokine production recovered in bronchoalveolar lavage fluid, oxidative stress, apoptosis, neutrophil infiltration, and lung tissue injury. Ac2-26 also decreased AnxA1 protein expression, inhibited the activation of nuclear factor-κB and mitogen-activated protein kinase pathways in the injured lung tissue. Finally, treatment with Boc2 abolished the protective action of Ac2-26. The results indicated that Ac2-26 had a protective effect against acute lung injury induced by IR, which may be via the activation of the FPR.

Expression of annexin A1 protein in esophageal carcinoma and its clinical significance

Objective To investigate the biological role of Annexin A1 protein in carcinogenesis and progression of esophageal carcinoma. Methods Annexin A1 protein level was analyzed by immunohistochemical assay in 94 cases of esophageal squamous carcinoma tissues and surrounding normal tissues. Annexin A1 overexpression and knockdown stable cell lines in human immortalized esophageal epithelial cell line SHEE were constructed by lentivirus. Cell proliferation of Annexin A1 overexpression and knockdown stable cell lines were analyzed by cell counting kit-8 (CCK-8). Cell invasion ability of Annexin A1 overexpression and knockdown stable cell lines were analyzed by transwell method. Cell colony forming ability in stable cell lines was analyzed by soft agar assay. Tumor formation in mice was analyzed by cell transplantation. Results Compared with the normal esophageal tissues, the expression levels of Annexin A1 protein in esophageal cancer tissues increased significantly (P=0.004). Compared with the control cell lines, proliferation (P=0.026) and invasion (P=0.017) ability in Annexin A1 protein overexpression cell lines significantly increased, while in the Annexin A1 protein knockdown cell lines, cell proliferation (P=0.019) and invasion (P=0.023) ability significantly decreased. Compared with the control cell lines, the clonal formation ability of Annexin A1 overexpression cell lines significantly enhanced(P=0.022), while the ability of clones formation in Annexin A1 protein knockdown cell line significantly decreased (P=0.035). In vivo tumor formation test showed that the tumor formation rate in Annexin A1 protein overexpressing cell lines significantly increased compared with control cell lines (P=0.001). Conclusion Annexin A1 protein overexpressed in esophageal carcinoma tissues, which was involved in the growth, invasion and tumorigenesis of esophageal cancer cells. Key words: Annexin A1 protein; Esophageal carcinoma; Proliferation; Invasion; Tumorigenesis