S100A11: diverse function and pathology corresponding to different target proteins

Comparative transcriptome analysis of albino northern snakehead (Channa argus) reveals its various collagen-related DEGs in caudal fin cells

The albino northern snakehead (Channa argus) is an aquaculture species characterized by heritable albino body color, in contrast to the typical coloration. Additionally, there are gray- and golden-finned individuals, which exhibit distinct coloration in their caudal fins. We performed RNA-seq to profile the transcriptome of caudal fin tissues in albino gray-finned and golden-finned C. argus, contrasting these with normal morphs to elucidate the differences between the two groups. A total of 137,130 unigenes were identified in this study. Gene Ontology (GO) analysis showed that the identified DEGs were significantly enriched in cellular components related to cytoplasm. So far, 379 common DEGs have been identified in all three groups. Notably, we observed more DEGs in golden-finned individuals compared to gray-finned individuals. We also revealed that golden-finned individuals were enriched in collagen-related pathways compared with normal individuals. The enriched DEGs of collagen components include collagen I of COL1A1 and COL1A2, collagen II of COL2A1, collagen V of COL5A1 and COL5A2, collagen VI of COL6A1 and COL6A3, collagen IX of COL9A3, collagen X of COL10A1, collagen XI of COL11A2, collagen XII of COL12A1, collagen XVI of COL16A1, collagen XVIII of COL18A1 and decorin (DCN), all of which play a role in modulating the collagen matrix. In golden-finned albino fish, collagen-related genes were downregulated, suggesting that despite the abundance of collagen types in their caudal fin cells, gene expression was slightly limited. This work provides valuable genetic insights into collagen variation in albino C. argus, lays the foundation for research on collagen genes and is crucial for the development and utilization of fish-derived collagen as a biomaterial for tissue engineering and biomedical applications.

Modeling the Annexin A1-S100A11 heterotetramer: a molecular dynamics investigation of structure and correlated motion

Annexin A1 (A1) has been shown to form a tetrameric complex (A1t) with S100A11 which is implicated in calcium homeostasis and EGFR pathways. In this work, a full-length model of the A1t was generated for the first time. Multiple molecular dynamics simulations were performed on the complete A1t model for several hundred nanoseconds each to assess the structure and dynamics of A1t. These simulations yielded three structures for the A1 N-terminus (ND) which were identified via principal component analysis. The orientations and interactions of the first 11 A1-ND residues for all three structures were conserved, and their binding modes were strikingly similar to those of the Annexin A2 N-terminus in the Annexin A2-p11 tetramer. In this study, we provided detailed atomistic information for the A1t. Strong interactions were identified within the A1t between the A1-ND and both S100A11 monomers. Residues M3, V4, S5, E6, L8, K9, W12, E15, and E18 of A1 were the strongest interactions between A1 and the S100A11 dimer. The different conformations of the A1t were attributed to the interaction between W12 of the A1-ND with M63 of S100A11 which caused a kink in the A1-ND. Cross-correlation analysis revealed strong correlated motion throughout the A1t. Strong positive correlation was observed between the ND and S100A11 in all simulations regardless of conformation. This work suggests that the stable binding of the first 11 residues of A1-ND to S100A11 is potentially a theme for Annexin-S100 complexes and that the flexibility of the A1-ND allows for multiple conformations of the A1t.Communicated by Ramaswamy H. Sarma.

Loss of chromosome Y in regulatory T cells

BACKGROUND

Mosaic loss of chromosome Y (LOY) in leukocytes is the most prevalent somatic aneuploidy in aging humans. Men with LOY have increased risks of all-cause mortality and the major causes of death, including many forms of cancer. It has been suggested that the association between LOY and disease risk depends on what type of leukocyte is affected with Y loss, with prostate cancer patients showing higher levels of LOY in CD4 + T lymphocytes. In previous studies, Y loss has however been observed at relatively low levels in this cell type. This motivated us to investigate whether specific subsets of CD4 + T lymphocytes are particularly affected by LOY. Publicly available, T lymphocyte enriched, single-cell RNA sequencing datasets from patients with liver, lung or colorectal cancer were used to study how LOY affects different subtypes of T lymphocyte. To validate the observations from the public data, we also generated a single-cell RNA sequencing dataset comprised of 23 PBMC samples and 32 CD4 + T lymphocytes enriched samples.

RESULTS

Regulatory T cells had significantly more LOY than any other studied T lymphocytes subtype. Furthermore, LOY in regulatory T cells increased the ratio of regulatory T cells compared with other T lymphocyte subtypes, indicating an effect of Y loss on lymphocyte differentiation. This was supported by developmental trajectory analysis of CD4 + T lymphocytes culminating in the regulatory T cells cluster most heavily affected by LOY. Finally, we identify dysregulation of 465 genes in regulatory T cells with Y loss, many involved in the immunosuppressive functions and development of regulatory T cells.

CONCLUSIONS

Here, we show that regulatory T cells are particularly affected by Y loss, resulting in an increased fraction of regulatory T cells and dysregulated immune functions. Considering that regulatory T cells plays a critical role in the process of immunosuppression; this enrichment for regulatory T cells with LOY might contribute to the increased risk for cancer observed among men with Y loss in leukocytes.

Downregulation of S100A11 promotes T cell infiltration by regulating cancer-associated fibroblasts in prostate cancer

OBJECTIVE

This study aims at revealing the relationship between S100A11 and cancer-associated fibroblasts (CAFs) in prostate cancer and improving T cell infiltration into solid tumors.

METHODS

H&E, IHC and Sirius red staining were used to detect the stroma content in prostate cancer tissues. Stable S100A11 knockdown cell lines DU 145, 22Rv1, RM-1 and NOR-10 were established by lentivirus transfection. Co-culture system of RM-1 and CAFs was established. CCK-8, wound healing and transwell were proceeded to determine proliferation, migration and invasion of prostate cancer cells. Stably knocked-down RM-1 and CAFs were co-injected into C57BL/6 mice to detect the role of S100A11 in vivo. CAFs, CD4+ T cell and CD8+ T cell in these tumors were assessed by IF. T cell profile was analyzed by flow cytometry.

RESULTS

A significant amount of stroma exists in prostate cancer tissues. Downregulation of S100A11 inhibits proliferation, migration and invasion of human prostate cancer cells in vitro, and suppresses the expression of cancer-associated fibroblasts (CAFs) in vivo. Knockdown of S100A11 enhances the inhibitory effect of Erdafitinib on CAFs in both the co-culture system and in vivo. The combined knockdown of S100A11 in tumor cells and CAFs shows a superior therapeutic effect compared to the individual knockdown in tumor cells alone. Knockdown of S100A11, both in RM-1 and CAFs, combined with Erdafitinib treatment reduces tumorigenicity by suppressing the content of CAFs and increasing the infiltration of CD4+ T cell and effective CD8+ T cell in tumor.

CONCLUSION

Downregulation of S100A11 plays a crucial role in enhancing the therapeutic response to Erdafitinib and reversing immunosuppressive tumor microenvironment.

S100A11 promotes focal adhesion disassembly via myosin II-driven contractility and Piezo1-mediated Ca2+ entry

S100A11 is a small Ca2+-activatable protein known to localize along stress fibers (SFs). Analyzing S100A11 localization in HeLa and U2OS cells further revealed S100A11 enrichment at focal adhesions (FAs). Strikingly, S100A11 levels at FAs increased sharply, yet transiently, just before FA disassembly. Elevating intracellular Ca2+ levels with ionomycin stimulated both S100A11 recruitment and subsequent FA disassembly. However, pre-incubation with the non-muscle myosin II (NMII) inhibitor blebbistatin or with an inhibitor of the stretch-activatable Ca2+ channel Piezo1 suppressed S100A11 recruitment, implicating S100A11 in an actomyosin-driven FA recruitment mechanism involving Piezo1-dependent Ca2+ influx. Applying external forces on peripheral FAs likewise recruited S100A11 to FAs even if NMII activity was inhibited, corroborating the mechanosensitive recruitment mechanism of S100A11. However, extracellular Ca2+ and Piezo1 function were indispensable, indicating that NMII contraction forces act upstream of Piezo1-mediated Ca2+ influx, in turn leading to S100A11 activation and FA recruitment. S100A11-knockout cells display enlarged FAs and had delayed FA disassembly during cell membrane retraction, consistent with impaired FA turnover in these cells. Our results thus demonstrate a novel function for S100A11 in promoting actomyosin contractility-driven FA disassembly.

Hepatic DDAH1 mitigates hepatic steatosis and insulin resistance in obese mice: Involvement of reduced S100A11 expression

Dimethylarginine dimethylaminohydrolase 1 (DDAH1) is an important regulator of plasma asymmetric dimethylarginine (ADMA) levels, which are associated with insulin resistance in patients with nonalcoholic fatty liver disease (NAFLD). To elucidate the role of hepatic DDAH1 in the pathogenesis of NAFLD, we used hepatocyte-specific Ddah1-knockout mice (Ddah1HKO) to examine the progress of high-fat diet (HFD)-induced NAFLD. Compared to diet-matched flox/flox littermates (Ddah1f/f), Ddah1HKO mice exhibited higher serum ADMA levels. After HFD feeding for 16 weeks, Ddah1HKO mice developed more severe liver steatosis and worse insulin resistance than Ddah1f/f mice. On the contrary, overexpression of DDAH1 attenuated the NAFLD-like phenotype in HFD-fed mice and ob/ob mice. RNA-seq analysis showed that DDAH1 affects NF-κB signaling, lipid metabolic processes, and immune system processes in fatty livers. Furthermore, DDAH1 reduces S100 calcium-binding protein A11 (S100A11) possibly via NF-κB, JNK and oxidative stress-dependent manner in fatty livers. Knockdown of hepatic S100a11 by an AAV8-shS100a11 vector alleviated hepatic steatosis and insulin resistance in HFD-fed Ddah1HKO mice. In summary, our results suggested that the liver DDAH1/S100A11 axis has a marked effect on liver lipid metabolism in obese mice. Strategies to increase liver DDAH1 activity or decrease S100A11 expression could be a valuable approach for NAFLD therapy.

Association between serum S100A11 levels and glucose metabolism in diabetic process

BACKGROUND

Diabetes mellitus (DM) is a prevalent non-communicable metabolic disease, and S100A11 is a newly identified gene closely related to metabolism. The association of S100A11 with diabetes is unclear. This study aimed to assess the relationship between S100A11 and markers of glucose metabolism in patients with different glucose tolerance and gender.

METHODS

This study included 97 participants. Baseline data were obtained, and the serum levels of S100A11 and metabolic markers (glycated hemoglobin [HbA1c], insulin release test, and oral glucose tolerance test) were measured. Linear and nonlinear correlations between serum S100A11 levels and HOMA-IR, HOMA of β, HbA1c, insulin sensitivity index (ISI), corrected insulin response (CIR), and oral disposition index (DIo) were analyzed. The expression of S100A11 was also detected in mice.

RESULTS

Serum S100A11 levels increased in patients with impaired glucose tolerance (IGT) of both genders. S100A11 mRNA and protein expression increased in obese mice. There were nonlinear correlations between S10011 levels and CIR, FPI, HOMA-IR, whole-body ISI in the IGT group. S100A11 was nonlinearly correlated with HOMA-IR, hepatic ISI, FPG, FPI, and HbA1c in the DM group. In the male group, S100A11 was linearly correlated with HOMA-IR and nonlinearly correlated with DIo (derived from hepatic ISI) and HbA1c. In the female population, S100A11 was nonlinearly correlated with CIR.

CONCLUSIONS

Serum S100A11 levels were highly expressed in patients with IGT and in the liver of obese mice. In addition, there were linear and nonlinear correlations between S100A11 and markers of glucose metabolism, demonstrating that S100A11 has a role in diabetes. Trial registration ChiCTR1900026990.

S100 Proteins in Fatty Liver Disease and Hepatocellular Carcinoma

Non-alcoholic fatty liver disease (NAFLD) is a highly prevalent and slow progressing hepatic pathology characterized by different stages of increasing severity which can ultimately give rise to the development of hepatocellular carcinoma (HCC). Besides drastic lifestyle changes, few drugs are effective to some extent alleviate NAFLD and HCC remains a poorly curable cancer. Among the deregulated molecular mechanisms promoting NAFLD and HCC, several members of the S100 proteins family appear to play an important role in the development of hepatic steatosis, non-alcoholic steatohepatitis (NASH) and HCC. Specific members of this Ca²⁺-binding protein family are indeed significantly overexpressed in either parenchymal or non-parenchymal liver cells, where they exert pleiotropic pathological functions driving NAFLD/NASH to severe stages and/or cancer development. The aberrant activity of S100 specific isoforms has also been reported to drive malignancy in liver cancers. Herein, we discuss the implication of several key members of this family, e.g., S100A4, S100A6, S100A8, S100A9 and S100A11, in NAFLD and HCC, with a particular focus on their intracellular versus extracellular functions in different hepatic cell types. Their clinical relevance as non-invasive diagnostic/prognostic biomarkers for the different stages of NAFLD and HCC, or their pharmacological targeting for therapeutic purpose, is further debated.

Transcriptome Analyses Provide Insights into the Auditory Function in Trachemys scripta elegans

An auditory ability is essential for communication in vertebrates, and considerable attention has been paid to auditory sensitivity in mammals, birds, and frogs. Turtles were thought to be deaf for a long time; however, recent studies have confirmed the presence of an auditory ability in Trachemys scripta elegans as well as sex-related differences in hearing sensitivity. Earlier studies mainly focused on the morphological and physiological functions of the hearing organ in turtles; thus, the gene expression patterns remain unclear. In this study, 36 transcriptomes from six tissues (inner ear, tympanic membrane, brain, eye, lung, and muscle) were sequenced to explore the gene expression patterns of the hearing system in T. scripta elegans. A weighted gene co-expression network analysis revealed that hub genes related to the inner ear and tympanic membrane are involved in development and signal transduction. Moreover, we identified six differently expressed genes (GABRA1, GABRG2, GABBR2, GNAO1, SLC38A1, and SLC12A5) related to the GABAergic synapse pathway as candidate genes to explain the differences in sexually dimorphic hearing sensitivity. Collectively, this study provides a critical foundation for genetic research on auditory functions in turtles.

The Role of the S100 Protein Family in Glioma

The S100 protein family consists of 25 members and share a common structure defined in part by the Ca²⁺ binding EF-hand motif. Multiple members' dysregulated expression is associated with progression, diagnosis and prognosis in a broad range of diseases, especially in tumors. They could exert wide range of functions both in intracellular and extracellular, including cell proliferation, cell differentiation, cell motility, enzyme activities, immune responses, cytoskeleton dynamics, Ca²⁺ homeostasis and angiogenesis. Gliomas are the most prevalent primary tumors of the brain and spinal cord with multiple subtypes that are diagnosed and classified based on histopathology. Up to now the role of several S100 proteins in gliomas have been explored. S100A8, S100A9 and S100B were highly expression in serum and may present as a marker correlated with survival and prognosis of glioma patients. Individual member was confirmed as a new regulator of glioma stem cells (GSCs) and a mediator of mesenchymal transition in glioblastoma (GBM). Additionally, several members up- or downregulation have been reported to involve in the development of glioma by interacting with signaling pathways and target proteins. Here we detail S100 proteins that are associated with glioma, and discuss their potential effects on progression, diagnosis and prognosis.

Tranilast inhibits angiotensin II-induced myocardial fibrosis through S100A11/ transforming growth factor-β (TGF-β1)/Smad axis

Tranilast has an ameliorative effect on myocardial fibrosis (MF), but the specific mechanism has not been studied. S100A11 is a key regulator of collagen expression in MF. In this paper, we will study the regulatory roles of Tranilast and S100A11 in MF. After the introduction of angiotensin II (AngII) to Human cardiac fibroblasts (HCF), Tranilast was administered. CCK-8 kit was used to detect cell viability. Wound Healing assay detected cell migration, and Western blot was used to detect the expression of migration-related proteins and proteins related to extracellular matrix synthesis. The expression of α-SMA was detected by immunofluorescence (IF). The expression of S100A11 was detected by qPCR and Western blot, and then S100A11 was overexpressed by cell transfection technology, so as to explore the mechanism by which Tranilast regulated MF. In addition, the expression of TGF-β1/Smad pathway related proteins was detected by Western blot. Tranilast inhibited Ang II–induced over-proliferation, migration and fibrosis of human cardiac fibroblasts (HCF), and simultaneously significantly decreased S100A11 expression was observed. Overexpression of S100A11 reversed the inhibition of Tranilast on AngII–induced over-proliferation, migration, and fibrosis in HCF, accompanied by activation of the TGF-β1/Smad pathway. Overall, Tranilast inhibits angiotensin II-induced myocardial fibrosis through S100A11/TGF-β1/Smad axis.

The Calcium Binding Protein S100A11 and Its Roles in Diseases

The calcium binding protein S100 family in humans contains 21 known members, with each possessing a molecular weight between 10 and 14 kDa. These proteins are characterized by a unique helix-loop-helix EF hand motif, and often form dimers and multimers. The S100 family mainly exists in vertebrates and exerts its biological functions both inside cells as a calcium sensor/binding protein, as well as outside cells. S100A11, a member of the S100 family, may mediate signal transduction in response to internal or external stimuli and it plays various roles in different diseases such as cancers, metabolic disease, neurological diseases, and vascular calcification. In addition, it can function as chemotactic agent in inflammatory disease. In this review, we first detail the discovery of S100 proteins and their structural features, and then specifically focus on the tissue and organ expression of S100A11. We also summarize its biological activities and roles in different disease and signaling pathways, providing an overview of S100A11 research thus far.

S100A14 promotes progression and gemcitabine resistance in pancreatic cancer

S100 calcium binding protein A14 (S100A14) plays an important role in the progression of several types of cancer. However, its roles in pancreatic ductal adenocarcinoma (PDAC) are largely unexplored. Here, we characterized the functional roles of S100A14 in the progression and chemoresistance of PDAC. Gene expression microarray identified that S100A14 was significantly highly expressed in four pairs of human PDAC tumor compared with corresponding non-tumor tissues genes. Quantitative reverse transcription PCR (qRT-PCR), western blotting and immunohistochemical staining (IHC) showed that S100A14 was frequently overexpressed in PDAC cell lines and tissues. Moreover, expression level of S100A14 was positively correlated to advanced cancer stages. Further, Kaplan-Meier survival analysis suggested that PDAC patients with low S100A14 expression had longer overall survival in TCGA PDAC datasets. Transient overexpressing of S100A14 promoted cell proliferation, anchorage-independent colony formation, cell migration and invasion in cell lines with low endogenous S100A14 levels, while transient silencing of S100A14 inhibited cell proliferation, anchorage-independent colony formation, cell migration and invasion in cell lines with high endogenous S100A14 levels. Persistent knockdown of S100A14 by transducing shRNAs carrying lentivirus inhibited subcutaneous tumor formation in nude mice, and sensitized the PDAC cells to gemcitabine treatment. Taken together, S100A14 exhibited oncogenic properties by promoting cell proliferation, transformation, migration and invasion, and enhanced in vivo tumor growth. More importantly, inhibition of S100A14 could effectively abrogate the cancerous properties of the PDAC cells. Our study indicated that S100A14 was a valuable target for the development of therapeutic strategy, as well as a diagnostic and prognosis biomarker for PDAC patients.

S100A11 Promotes Glioma Cell Proliferation and Predicts Grade-Correlated Unfavorable Prognosis

The prognosis of glioma is significantly correlated with the pathological grades; however, the correlations between the prognostic biomarkers with pathological grades have not been elucidated. S100A11 is involved in a variety of malignant biological processes of tumor, whereas its biological and clinicopathological features on glioma remain unclear. In this study, the S100A11 expression and clinical information were obtained from the public databases (TCGA, GEPIA2) to analyze its correlations with the pathological grade and the prognosis of glioma patients. We then verified the expression of S100A11 by immunohistochemistry staining. The effects of S100A11 on the proliferation of glioma cells were confirmed by cytological function assays (CCK-8, Flow cytometry, Clone formation assay) in vitro, the role of S100A11 in regulation of glioma growth was determined by xenograft model assay. We observed that S100A11 expression positively correlated with the pathological grades, while negatively correlated with the survival time of patients. In cytological analysis, we found the proliferations of glioma cell lines were significantly inhibited in vitro (P < 0.05) after interfering S100A11 expression via shRNAs. The cell cycle was blocked at G0/G1 stage. The ability of clone formation was significantly decreased, and the tumorigenicity in vivo was weakened (P < 0.05). In summary, S100A11 was over-expressed in gliomas and positively correlated with the pathological grades. Interfering the expression of S100A11 significantly inhibited the proliferation of glioma in vitro and the tumorigenicity in vivo (P < 0.05). In conclusion, S100A11 might be considered as a potential biomarker in glioma.

An Integrated Bioinformatic Analysis of the S100 Gene Family for the Prognosis of Colorectal Cancer

Background

S100 family genes exclusively encode at least 20 calcium-binding proteins, which possess a wide spectrum of intracellular and extracellular functions in vertebrates. Multiple lines of evidences suggest that dysregulated S100 proteins are associated with human malignancies including colorectal cancer (CRC). However, the diverse expression patterns and prognostic roles of distinct S100 genes in CRC have not been fully elucidated.

Methods

In the current study, we analyzed the mRNA expression levels of S100 family genes and proteins and their associations with the survival of CRC patients using the Oncomine analysis and GEPIA databases. Expressions and mutations of S100 family genes were analyzed using the cBioPortal, and protein-protein interaction (PPI) networks of S100 proteins and their mutation-related coexpressed genes were analyzed using STRING and Cytoscape.

Results

We observed that the mRNA expression levels of S100A2, S100A3, S100A9, S100A11, and S100P were higher and the level of S100B was lower in CRC tissues than those in normal colon mucosa. A high S100A10 levels was associated with advanced-stage CRC. Results from GEPIA database showed that highly expressed S100A1 was correlated with worse overall survival (OS) and disease-free survival (DFS) and that overexpressions of S100A2 and S100A11 were associated with poor DFS of CRC, indicating that S100A1, S100A2, and S100A11 are potential prognostic markers. Unexpectedly, most of S100 family genes showed no significant prognostic values in CRC.

Conclusions

Our findings, though still need to be ascertained, offer novel insights into the prognostic implications of the S100 family in CRC and will inspire more clinical trials to explore potential S100-targeted inhibitors for the treatment of CRC.

Comprehensive analysis of the expression and prognosis for S100 in human ovarian cancer: A STROBE study

S100 family members are frequently deregulated in human malignancies, including ovarian cancer. However, the prognostic roles of each individual S100 family member in ovarian cancer (OC) patients remain elusive. In the present study, we assessed the prognostic roles and molecular function of 20 individual members of the S100 family in OC patients using GEPIA, Kaplan-Meier plotter, SurvExpress, GeneMANIA and Funrich database. Our results indicated that the mRNA expression levels of S100A1, S100A2, S100A4, S100A5, S100A11, S100A14, and S100A16 were significantly upregulated in patients with OC, and high mRNA expression of S100A1, S100A3, S100A5, S100A6, and S100A13 were significantly correlated with better overall survival, while increased S100A2, S100A7A, S100A10, and S100A11 mRNA expressions were associated with worse prognosis in OC patients. In stratified analysis, the trends of high expression of individual S100 members were nearly the same in different pathological grade, clinical stage, TP53 mutation status, and treatment. More importantly, S100 family signatures may be useful potential prognostic markers for OC. These findings suggest that S100 family plays a vital role in prognostic value and could potentially be an S100-targeted inhibitors for OC patients.

S100A11 Promotes Liver Steatosis via FOXO1-Mediated Autophagy and Lipogenesis

BACKGROUND & AIMS

Nonalcoholic fatty liver disease (NAFLD) is becoming a severe liver disorder worldwide. Autophagy plays a critical role in liver steatosis. However, the role of autophagy in NAFLD remains exclusive and under debate. In this study, we investigated the role of S100 calcium binding protein A11 (S100A11) in the pathogenesis of hepatic steatosis.

METHODS

We performed liver proteomics in a well-established tree shrew model of NAFLD. The expression of S100A11 in different models of NAFLD was detected by Western blot and/or quantitative polymerase chain reaction. Liver S100A11 overexpression mice were generated by injecting a recombinant adenovirus gene transfer vector through the tail vein and then induced by a high-fat and high-cholesterol diet. Cell lines with S100a11 stable overexpression were established with a recombinant lentiviral vector. The lipid content was measured with either Bodipy staining, Oil Red O staining, gas chromatography, or a triglyceride kit. The autophagy and lipogenesis were detected in vitro and in vivo by Western blot and quantitative polymerase chain reaction. The functions of Sirtuin 1, histone deacetylase 6 (HDAC6), and FOXO1 were inhibited by specific inhibitors. The interactions between related proteins were analyzed by a co-immunoprecipitation assay and immunofluorescence analysis.

RESULTS

The expression of S100A11 was up-regulated significantly in a time-dependent manner in the tree shrew model of NAFLD. S100A11 expression was induced consistently in oleic acid-treated liver cells as well as the livers of mice fed a high-fat diet and NAFLD patients. Both in vitro and in vivo overexpression of S100A11 could induce hepatic lipid accumulation. Mechanistically, overexpression of S100A11 activated an autophagy and lipogenesis process through up-regulation and acetylation of the transcriptional factor FOXO1, consequently promoting lipogenesis and lipid accumulation in vitro and in vivo. Inhibition of HDAC6, a deacetylase of FOXO1, showed similar phenotypes to S100A11 overexpression in Hepa 1-6 cells. S100A11 interacted with HDAC6 to inhibit its activity, leading to the release and activation of FOXO1. Under S100A11 overexpression, the inhibition of FOXO1 and autophagy could alleviate the activated autophagy as well as up-regulated lipogenic genes. Both FOXO1 and autophagy inhibition and Dgat2 deletion could reduce liver cell lipid accumulation significantly.

CONCLUSIONS

A high-fat diet promotes liver S100A11 expression, which may interact with HDAC6 to block its binding to FOXO1, releasing or increasing the acetylation of FOXO1, thus activating autophagy and lipogenesis, and accelerating lipid accumulation and liver steatosis. These findings indicate a completely novel S100A11-HDAC6-FOXO1 axis in the regulation of autophagy and liver steatosis, providing potential possibilities for the treatment of NAFLD.

Friend or Foe: S100 Proteins in Cancer

S100 proteins are widely expressed small molecular EF-hand calcium-binding proteins of vertebrates, which are involved in numerous cellular processes, such as Ca²⁺ homeostasis, proliferation, apoptosis, differentiation, and inflammation. Although the complex network of S100 signalling is by far not fully deciphered, several S100 family members could be linked to a variety of diseases, such as inflammatory disorders, neurological diseases, and also cancer. The research of the past decades revealed that S100 proteins play a crucial role in the development and progression of many cancer types, such as breast cancer, lung cancer, and melanoma. Hence, S100 family members have also been shown to be promising diagnostic markers and possible novel targets for therapy. However, the current knowledge of S100 proteins is limited and more attention to this unique group of proteins is needed. Therefore, this review article summarises S100 proteins and their relation in different cancer types, while also providing an overview of novel therapeutic strategies for targeting S100 proteins for cancer treatment.

Serum S100A6, S100A8, S100A9 and S100A11 proteins in colorectal neoplasia: results of a single centre prospective study

S100 proteins are involved in biological events related to colorectal carcinogenesis. Aim of this prospective study was to assess serum concentration of S100A6, A8, A9 and A11 proteins in patients with colorectal neoplasia. Eighty-four subjects were enrolled: 20 controls (average risk population with normal findings on colonoscopy; 7 men, 13 women, age 23-74, mean 55 ± 14), 20 patients with non-advanced colorectal adenoma (non-AA, 10 men, 10 women, age 41-82, mean 62 ± 11), 22 with advanced colorectal adenoma (AA, 15 men, 7 women, age 49-80, mean 64 ± 8) and 22 with colorectal cancer (CRC, 12 men, 10 women, age 49-86, mean 69 ± 10). Peripheral venous blood was obtained. Serum S100 proteins were investigated by enzyme immunoassay technique. Serum S100A6 was significantly lower in CRC (mean 8530 ± 4743 ng/L), p = .035 compared to controls (mean 11308 ± 2968 ng/L). Serum S100A8 was significantly higher in AA (median 11955 ng/L, IQR 2681-34756 ng/L), p = .009 and in CRC (median 27532 ng/L, IQR 6794-35092 ng/L), p < .001 compared to controls (median 2513 ng/L, IQR 2111-4881 ng/L). Serum S100A9 concentrations did not differ between any tested group and controls, p > .05. Serum concentration of S100A11 was significantly lower in non-AA (mean 3.5 ± 2.4 μg/L), p = .004 and in CRC (mean 3.4 ± 2.4 μg/L), p = .002 compared to controls (mean 5.9 ± 2.5 μg/L). Sensitivity and specificity for S100A8 protein in patients with CRC were 94% and 73%; positive predictive value 68% and negative predictive value 95%. Patients with colorectal neoplasia have significantly lower serum S100A6 and S100A11 levels, significantly higher S100A8 and unaltered serum S100A9 levels.

Consequences of Haemorrhagic Smolt Syndrome (HSS) for the Immune Status of Atlantic salmon (Salmo salar L.) (Case Study)

Haemorrhagic smolt syndrome (HSS) is a disorder of unknown aetiology causing losses in the fresh water phase of Atlantic salmon farming. Normally, the mortality is limited and symptoms disappear upon seawater exposure. In this case study, classical HSS pathology with internal organ haemorrhages and nephrocalcinosis was diagnosed, and the losses were substantial. Microarray analyses of head kidney revealed association between HSS and enhanced expression of stress genes and proteins reducing bioavailability of iron, heme, and retinol. In parallel, suppression of multiple metabolic pathways was observed. Up-regulation of genes encoding acute phase proteins, complement, and lectins indicated mild inflammation but without characteristic features of viral or bacterial infections. Microarray analyses highlighted several members of tumor necrosis factor receptor superfamily that may control development of B-cell immunity. Examination of IgM at the mRNA and protein levels showed the impact of HSS on vaccine responses. In fish without HSS symptoms (non-HSS), titres of vaccine specific antibodies to A-layer of Aeromonas salmonicida subsp. salmonicida and Moritella viscosa and antibodies binding to DNP-keyhole limpet hemocyanin (DNP-KLH), which are presumably polyreactive, were respectively four- and 14-fold higher than in HSS-diseased fish. Parallel sequencing of variable regions of immunoglobulin Mrevealed a larger size of most abundant clonotypes shared by multiple individuals in the non-HSS group. The results of the current case study indicated that, in addition to direct damage, HSS suppresses humoral immune responses including the production of specific and polyreactive antibodies.

An Update to Calcium Binding Proteins

Ca²⁺ binding proteins (CBP) are of key importance for calcium to play its role as a pivotal second messenger. CBP bind Ca²⁺ in specific domains, contributing to the regulation of its concentration at the cytosol and intracellular stores. They also participate in numerous cellular functions by acting as Ca²⁺ transporters across cell membranes or as Ca²⁺-modulated sensors, i.e. decoding Ca²⁺ signals. Since CBP are integral to normal physiological processes, possible roles for them in a variety of diseases has attracted growing interest in recent years. In addition, research on CBP has been reinforced with advances in the structural characterization of new CBP family members. In this chapter we have updated a previous review on CBP, covering in more depth potential participation in physiopathological processes and candidacy for pharmacological targets in many diseases. We review intracellular CBP that contain the structural EF-hand domain: parvalbumin, calmodulin, S100 proteins, calcineurin and neuronal Ca²⁺ sensor proteins (NCS). We also address intracellular CBP lacking the EF-hand domain: annexins, CBP within intracellular Ca²⁺ stores (paying special attention to calreticulin and calsequestrin), proteins that contain a C2 domain (such as protein kinase C (PKC) or synaptotagmin) and other proteins of interest, such as regucalcin or proprotein convertase subtisilin kexins (PCSK). Finally, we summarise the latest findings on extracellular CBP, classified according to their Ca²⁺ binding structures: (i) EF-hand domains; (ii) EGF-like domains; (iii) ɣ-carboxyl glutamic acid (GLA)-rich domains; (iv) cadherin domains; (v) Ca²⁺-dependent (C)-type lectin-like domains; (vi) Ca²⁺-binding pockets of family C G-protein-coupled receptors.

S100 Calcium Binding Protein A11 (S100A11) Promotes The Proliferation, Migration And Invasion Of Cervical Cancer Cells, And Activates Wnt/β-Catenin Signaling

Purpose

This study is aimed to investigate the specific regulatory role of S100 calcium binding protein A11 (S100A11) on cervical cancer (CC), and reveal the potential mechanisms relating to Wnt/β-catenin signaling.

Patients and methods

The expression of S100A11 in cervical squamous cell carcinoma (CSCC), adjacent non-cancerous, cervical intraepithelial neoplasia (CIN), and normal cervical tissues was detected by quantitative real-time PCR and/or immunohistochemistry. After transfection of pENTER-S100A11 or sh-S100A11-1/sh-S100A11-2, the viability, cell cycle, migration and invasion of C33A or SiHa cells were detected. The tumor volume and tumor weight were measured after injection of transfected C33A cells into mice. The expression of E-caherin (CDH2), N-caherin (CDH1), β-catenin (CTNNB1), and c-Myc (MYC) in C33A and SiHa cells was detected by Western blot.

Results

The expression of S100A11 was significantly higher in CSCC tissues than in adjacent non-cancerous, CIN, and normal cervical tissues (P < 0.05). S100A11 expression was positively correlated with the FIGO stage and lymph node metastasis of CSCC patients (P < 0.05). The transfection of pENTER-S100A11 into C33A cells significantly increased the cell viability, the percentage of cells in G2/M phase, the numbers of migratory and invasive cells, as well as the tumor volume and weight in mice (P < 0.05). Overexpression of S100A11 also significantly downregulated E-caherin, and upregulated N-caherin, β-catenin, and c-Myc in C33A cells (P < 0.05). The transfection of sh-S100A11-1/sh-S100A11-2 exhibited the opposite results to that of pENTER-S100A11 on SiHa cells.

Conclusion

Overexpression of S100A11 promotes the proliferation, migration, invasion, and epithelial-mesenchymal transition of CC cells, and activates Wnt/β-catenin signaling.

Thymic Microenvironment Is Modified by Malnutrition and Leishmania infantum Infection

Detrimental effects of malnutrition on immune responses to pathogens have long been recognized and it is considered a main risk factor for various infectious diseases, including visceral leishmaniasis (VL). Thymus is a target of both malnutrition and infection, but its role in the immune response to Leishmania infantum in malnourished individuals is barely studied. Because we previously observed thymic atrophy and significant reduction in cellularity and chemokine levels in malnourished mice infected with L. infantum, we postulated that the thymic microenvironment is severely compromised in those animals. To test this, we analyzed the microarchitecture of the organ and measured the protein abundance in its interstitial space in malnourished BALB/c mice infected or not with L. infantum. Malnourished-infected animals exhibited a significant reduction of the thymic cortex:medulla ratio and altered abundance of proteins secreted in the thymic interstitial fluid. Eighty-one percent of identified proteins are secreted by exosomes and malnourished-infected mice showed significant decrease in exosomal proteins, suggesting that exosomal carrier system, and therefore intrathymic communication, is dysregulated in those animals. Malnourished-infected mice also exhibited a significant increase in the abundance of proteins involved in lipid metabolism and tricarboxylic acid cycle, suggestive of a non-proliferative microenvironment. Accordingly, flow cytometry analysis revealed decreased proliferation of single positive and double positive T cells in those animals. Together, the reduced cortical area, decreased proliferation, and altered protein abundance suggest a dysfunctional thymic microenvironment where T cell migration, proliferation, and maturation are compromised, contributing for the thymic atrophy observed in malnourished animals. All these alterations could affect the control of the local and systemic infection, resulting in an impaired response to L. infantum infection.

S100A11 regulates renal carcinoma cell proliferation, invasion, and migration via the EGFR/Akt signaling pathway and E-cadherin

S100A11 is a S100 protein family member that contributes to cancer progression. Upregulated in human renal cancer tissues, S100A11 may be a prognostic marker for clear cell renal cell carcinoma, but how it functions in cancer is uncertain. Thus, we studied S100A11 and noted knockdown of S100A11 using short hairpin RNA, which inhibited proliferation, invasion, and migration of renal carcinoma cells as well as increased expression of E-cadherin and decreased expression of epidermal growth factor receptor/Akt in renal carcinoma cells. Therefore, S100A11 may be a key molecular target for treating renal carcinoma.

Annexin A1 localization and its relevance to cancer

Annexin A1 (ANXA1) is a Ca(2+)-regulated phospholipid-binding protein involved in various cell processes. ANXA1 was initially widely studied in inflammation resolution, but its overexpression was later reported in a large number of cancers. Further in-depth investigations have revealed that this protein could have many roles in cancer progression and act at different levels (from cancer initiation to metastasis). This is partly due to the location of ANXA1 in different cell compartments. ANXA1 can be nuclear, cytoplasmic and/or membrane associated. This last location allows ANXA1 to be proteolytically cleaved and/or to become accessible to its cognate partners, the formyl-peptide receptors. Indeed, in some cancers, ANXA1 is found at the cell surface, where it stimulates formyl-peptide receptors to trigger oncogenic pathways. In the present review, we look at the different locations of ANXA1 and their association with the deregulated pathways often observed in cancers. We have specifically detailed the non-classic pathways of ANXA1 externalization, the significance of its cleavage and the role of the ANXA1-formyl-peptide receptor complex in cancer progression.

Tudor staphylococcal nuclease drives chemoresistance of non-small cell lung carcinoma cells by regulating S100A11

Lung cancer is the leading cause of cancer-related deaths worldwide. Non-small cell lung cancer (NSCLC), the major lung cancer subtype, is characterized by high resistance to chemotherapy. Here we demonstrate that Tudor staphylococcal nuclease (SND1 or TSN) is overexpressed in NSCLC cell lines and tissues, and is important for maintaining NSCLC chemoresistance. Downregulation of TSN by RNAi in NSCLC cells led to strong potentiation of cell death in response to cisplatin. Silencing of TSN was accompanied by a significant decrease in S100A11 expression at both mRNA and protein level. Downregulation of S100A11 by RNAi resulted in enhanced sensitivity of NSCLC cells to cisplatin, oxaliplatin and 5-fluouracil. AACOCF₃, a phospholipase A₂ (PLA₂) inhibitor, strongly abrogated chemosensitization upon silencing of S100A11 suggesting that PLA₂ inhibition by S100A11 governs the chemoresistance of NSCLC. Moreover, silencing of S100A11 stimulated mitochondrial superoxide production, which was decreased by AACOCF₃, as well as N-acetyl-L-cysteine, which also mimicked the effect of PLA₂ inhibitor on NSCLC chemosensitization upon S100A11 silencing. Thus, we present the novel TSN-S100A11-PLA₂ axis regulating superoxide-dependent apoptosis, triggered by platinum-based chemotherapeutic agents in NSCLC that may be targeted by innovative cancer therapies.

Reactive Oxygen Species (ROS)-Activated ATM-Dependent Phosphorylation of Cytoplasmic Substrates Identified by Large-Scale Phosphoproteomics Screen

Ataxia-telangiectasia, mutated (ATM) protein plays a central role in phosphorylating a network of proteins in response to DNA damage. These proteins function in signaling pathways designed to maintain the stability of the genome and minimize the risk of disease by controlling cell cycle checkpoints, initiating DNA repair, and regulating gene expression. ATM kinase can be activated by a variety of stimuli, including oxidative stress. Here, we confirmed activation of cytoplasmic ATM by autophosphorylation at multiple sites. Then we employed a global quantitative phosphoproteomics approach to identify cytoplasmic proteins altered in their phosphorylation state in control and ataxia-telangiectasia (A-T) cells in response to oxidative damage. We demonstrated that ATM was activated by oxidative damage in the cytoplasm as well as in the nucleus and identified a total of 9,833 phosphorylation sites, including 6,686 high-confidence sites mapping to 2,536 unique proteins. A total of 62 differentially phosphorylated peptides were identified; of these, 43 were phosphorylated in control but not in A-T cells, and 19 varied in their level of phosphorylation. Motif enrichment analysis of phosphopeptides revealed that consensus ATM serine glutamine sites were overrepresented. When considering phosphorylation events, only observed in control cells (not observed in A-T cells), with predicted ATM sites phosphoSerine/phosphoThreonine glutamine, we narrowed this list to 11 candidate ATM-dependent cytoplasmic proteins. Two of these 11 were previously described as ATM substrates (HMGA1 and UIMCI/RAP80), another five were identified in a whole cell extract phosphoproteomic screens, and the remaining four proteins had not been identified previously in DNA damage response screens. We validated the phosphorylation of three of these proteins (oxidative stress responsive 1 (OSR1), HDGF, and ccdc82) as ATM dependent after H2O2 exposure, and another protein (S100A11) demonstrated ATM-dependence for translocation from the cytoplasm to the nucleus. These data provide new insights into the activation of ATM by oxidative stress through identification of novel substrates for ATM in the cytoplasm.

Role of S100 Proteins in Colorectal Carcinogenesis

The family of S100 proteins represents 25 relatively small (9-13 kD) calcium binding proteins. These proteins possess a broad spectrum of important intracellular and extracellular functions. Colorectal cancer is the third most common cancer in men (after lung and prostate cancer) and the second most frequent cancer in women (after breast cancer) worldwide. S100 proteins are involved in the colorectal carcinogenesis through different mechanisms: they enable proliferation, invasion, and migration of the tumour cells; furthermore, S100 proteins increase angiogenesis and activate NF-κβ signaling pathway, which plays a key role in the molecular pathogenesis especially of colitis-associated carcinoma. The expression of S100 proteins in the cancerous tissue and serum levels of S100 proteins might be used as a precise diagnostic and prognostic marker in patients with suspected or already diagnosed colorectal neoplasia. Possibly, in the future, S100 proteins will be a therapeutic target for tailored anticancer therapy.

Differences in brain gene transcription profiles advocate for an important role of cognitive function in upstream migration and water obstacles crossing in European eel

BACKGROUND

European eel is a panmictic species, whose decline has been recorded since the last 20 years. Among human-induced environmental factors of decline, the impact of water dams during species migration is questioned. The main issue of this study was to pinpoint phenotypic traits that predisposed glass eels to successful passage by water barriers. The approach of the study was individual-centred and without any a priori hypothesis on traits involved in the putative obstacles selective pressure. We analyzed the transcription level of 14,913 genes.

RESULTS

Transcriptome analysis of three tissues (brain, liver and muscle) from individuals sampled on three successive forebays separated by water obstacles indicated different gene transcription profiles in brain between the two upstream forebays. No differences in gene transcription levels were observed in liver and muscle samples among segments. A total of 26 genes were differentially transcribed in brain. These genes encode for, among others, keratins, cytokeratins, calcium binding proteins (S100 family), cofilin, calmodulin, claudin and thy-1 membrane glycoprotein. The functional analysis of these genes highlighted a putative role of cytoskeletal dynamics and synaptic plasticity in fish upstream migration.

CONCLUSION

Synaptic connections in brain are solicited while eels are climbing the obstacles with poorly designed fishways. Successful passage by such barriers can be related to spatial learning and spatial orientation abilities when fish is out of the water.

Significance of expression of S100A11 and 14-3-3 proteins in esophageal squamous cell carcinoma

AIM: To determine the correlation between invasion, migration and prognosis of esophageal squamous cell carcinoma (ESCC) and expression of S100A11 and 14-3-3 proteins.

METHODS: Sixty-eight previously untreated patients who underwent surgical excision of ESCC were included. The expression of S100A11 and 14-3-3 proteins was examined immunohistochemically in formalin-fixed paraffin-embedded primary tissue specimens. The relationships between the expression of S100A11 and 14-3-3 proteins, the clinicopathologic features of ESCC, and the survival rate of ESCC patients were analyzed. The correlation between S100A11 and 14-3-3 protein expression in ESCC was also analyzed.

RESULTS: The positive rates of S100A11 and 14-3-3 protein expression were significantly higher in ESCC than in normal esophageal tissues (55.9% vs 25.0%, 69.1% vs 33.3%, P < 0.05). S100A11 expression showed no significant correlation with gender, age, ethnicity, tumor size or infiltration depth (P > 0.05), but was significantly correlated with degree of differentiation, lymph node metastasis and clinical stage (P < 0.05). 14-3-3 expression showed no significant correlation with gender, age, ethnicity, or tumor size (P > 0.05), but was significantly correlated with degree of differentiation, depth of infiltration, lymph node metastasis and clinical stage (P < 0.05).

CONCLUSION: S100A11 and 14-3-3 may play a role in the occurrence and development of ESCC. The expression of S100A11 and14-3-3 is significantly related to tumor differentiation, lymph node metastasis and clinical stage, and they may be used to assess the malignant degree of ESCC.

Investigation of neutrophilic peptides in periprosthetic tissue by matrix-assisted laser desorption ionisation time-of-flight imaging mass spectrometry

PURPOSE

The accurate diagnosis of periprosthetic joint infection (PJI) relies on clinical investigation, laboratory parameters, radiological methods, sterile joint aspiration for synovial fluid leucocyte count and microbiological analysis and tissue sampling for histopathology. Due to the limits in specificity and sensitivity of these methods, molecular techniques and new biomarkers were introduced into the diagnostic procedure. Histological examination is related to the amount of neutrophils in the periprosthetic tissue in frozen sections and formalin-fixed paraffin embedded material (FFPE). However, the threshold of neutrophils per defined area of tissue among various studies is very inconsistent.

METHODS

We have applied matrix-assisted laser desorption ionisation time-of-flight imaging mass spectrometry (MALDI IMS) to a total of 32 periprosthetic tissue samples of patients with PJI to detect peptides associated with areas of neutrophil infiltration.

RESULTS

Specific peaks associated with a high amount of neutrophils were detected. Of these m/z peaks, four could be assigned to predictive neutrophil molecules. These peptides include annexin A1, calgizzarin (S100A11), calgranulin C (S100A12) and histone H2A. By MALDI IMS, these peptides could be shown to be co-localised with the infiltration of neutrophils in the immediate vicinity of the periprosthetic interface, whereas more distant areas did not show neutrophil invasion or infection-related peptides.

CONCLUSIONS

MALDI IMS is a new method allowing identification of neutrophil peptides in periprosthetic tissues and may be a surrogate for counting neutrophils as an objective parameter for PJI.

Quantitative proteomics study of protective effects of grape seed procyanidin B2 on diabetic cardiomyopathy in db/db mice

Diabetic cardiomyopathy is one of the major complications of diabetes mellitus. Oxidative stress appears to play a substantial role in cardiomyopathy. Grape seed procyanidin B2 (GSPB2) has been known as an anti-oxidant in treating diabetes mellitus; however, little is known about its effects and underlying mechanisms on diabetic cardiomyopathy. The present study is to explore the molecular targets of GSPB2 responsible for the anti-oxidative effects in db/db mice by quantitative proteomics. GSPB2 (30 mg/kg body weight/day) were intragastric administrated to db/db mice for 10 weeks. Proteomics of the heart tissue extracts by isobaric tags for relative and absolute quantification analysis was obtained from db/db mice. Our study provides important evidence that GSPB2 protect against cardiomyopathy in diabetes mellitus, which are believed to result from regulating the expression of key proteins involving cardiac fibrosis and proliferation. GSPB2 could be expected to become novel clinical application in fighting against diabetic cardiomyopathy.

Proteome analysis of coinfection of epithelial cells with Filifactor alocis and Porphyromonas gingivalis shows modulation of pathogen and host regulatory pathways

Changes in periodontal status are associated with shifts in the composition of the bacterial community in the periodontal pocket. The relative abundances of several newly recognized microbial species, including Filifactor alocis, as-yet-unculturable organisms, and other fastidious organisms have raised questions on their impact on disease development. We have previously reported that the virulence attributes of F. alocis are enhanced in coculture with Porphyromonas gingivalis. We have evaluated the proteome of host cells and F. alocis during a polymicrobial infection. Coinfection of epithelial cells with F. alocis and P. gingivalis strains showed approximately 20% to 30% more proteins than a monoinfection. Unlike F. alocis ATCC 35896, the D-62D strain expressed more proteins during coculture with P. gingivalis W83 than with P. gingivalis 33277. Proteins designated microbial surface component-recognizing adhesion matrix molecules (MSCRAMMs) and cell wall anchor proteins were highly upregulated during the polymicrobial infection. Ultrastructural analysis of the epithelial cells showed formation of membrane microdomains only during coinfection. The proteome profile of epithelial cells showed proteins related to cytoskeletal organization and gene expression and epigenetic modification to be in high abundance. Modulation of proteins involved in apoptotic and cell signaling pathways was noted during coinfection. The enhanced virulence potential of F. alocis may be related to the differential expression levels of several putative virulence factors and their effects on specific host cell pathways.

Joining S100 proteins and migration: for better or for worse, in sickness and in health

The vast diversity of S100 proteins has demonstrated a multitude of biological correlations with cell growth, cell differentiation and cell survival in numerous physiological and pathological conditions in all cells of the body. This review summarises some of the reported regulatory functions of S100 proteins (namely S100A1, S100A2, S100A4, S100A6, S100A7, S100A8/S100A9, S100A10, S100A11, S100A12, S100B and S100P) on cellular migration and invasion, established in both culture and animal model systems and the possible mechanisms that have been proposed to be responsible. These mechanisms involve intracellular events and components of the cytoskeletal organisation (actin/myosin filaments, intermediate filaments and microtubules) as well as extracellular signalling at different cell surface receptors (RAGE and integrins). Finally, we shall attempt to demonstrate how aberrant expression of the S100 proteins may lead to pathological events and human disorders and furthermore provide a rationale to possibly explain why the expression of some of the S100 proteins (mainly S100A4 and S100P) has led to conflicting results on motility, depending on the cells used.

S100 family signaling network and related proteins in pancreatic cancer (Review)

The occurrence and development of pancreatic cancer is a complex process convoluted by multi-pathogenies, multi-stages and multi-factors. S100 proteins are members of the S100 family that regulate multiple cellular pathways related to pancreatic cancer progression and metastasis. S100 proteins have a broad range of intracellular and extracellular functions, including the regulation of protein phosphorylation and enzyme activity, calcium homeostasis and the regulation of cytoskeletal components and transcriptional factors. S100 proteins interact with receptor for advanced glycation end-products (RAGE), p53 and p21, which play a role in the degradation of the extracellular matrix (ECM) and metastasis, and also interact with cytoskeletal proteins and the plasma membrane in pancreatic cancer progression and metastasis. S100A11 and S100P are significant tumor markers for pancreatic cancer and unfavorable predictors for the prognosis of patients who have undergone surgical resection. Recently, S100A2 has been suggested to be a negative prognostic biomarker in pancreatic cancer, and the expression of S100A6 may be an independent prognostic impact factor. The expression of S100A4 and S100P is associated with drug resistance, differentiation, metastasis and clinical outcome. This review summarizes the role and significance of the S100 family signaling network and related proteins in pancreatic cancer.

Functional proteomic analysis reveals the involvement of KIAA1199 in breast cancer growth, motility and invasiveness

Background

KIAA1199 is a recently identified novel gene that is up-regulated in human cancer with poor survival. Our proteomic study on signaling polarity in chemotactic cells revealed KIAA1199 as a novel protein target that may be involved in cellular chemotaxis and motility. In the present study, we examined the functional significance of KIAA1199 expression in breast cancer growth, motility and invasiveness.

Methods

We validated the previous microarray observation by tissue microarray immunohistochemistry using a TMA slide containing 12 breast tumor tissue cores and 12 corresponding normal tissues. We performed the shRNA-mediated knockdown of KIAA1199 in MDA-MB-231 and HS578T cells to study the role of this protein in cell proliferation, migration and apoptosis in vitro. We studied the effects of KIAA1199 knockdown in vivo in two groups of mice (n = 5). We carried out the SILAC LC-MS/MS based proteomic studies on the involvement of KIAA1199 in breast cancer.

Results

KIAA1199 mRNA and protein was significantly overexpressed in breast tumor specimens and cell lines as compared with non-neoplastic breast tissues from large-scale microarray and studies of breast cancer cell lines and tumors. To gain deeper insights into the novel role of KIAA1199 in breast cancer, we modulated KIAA1199 expression using shRNA-mediated knockdown in two breast cancer cell lines (MDA-MB-231 and HS578T), expressing higher levels of KIAA1199. The KIAA1199 knockdown cells showed reduced motility and cell proliferation in vitro. Moreover, when the knockdown cells were injected into the mammary fat pads of female athymic nude mice, there was a significant decrease in tumor incidence and growth. In addition, quantitative proteomic analysis revealed that knockdown of KIAA1199 in breast cancer (MDA-MB-231) cells affected a broad range of cellular functions including apoptosis, metabolism and cell motility.

Conclusions

Our findings indicate that KIAA1199 may play an important role in breast tumor growth and invasiveness, and that it may represent a novel target for biomarker development and a novel therapeutic target for breast cancer.

Resonance assignments of Ca²⁺-bound human S100A11

The S100 family belongs to the EF-hand calcium-binding proteins regulating a wide range of important cellular processes via protein-protein interactions. Most S100 proteins adopt a conformation of non-covalent homodimer for their functions. Calcium binding to the EF-hand motifs of S100 proteins is essential for triggering the structural changes, promoting exposure of hydrophobic regions necessary for target protein interactions. S100A11 is a protein found in diverse tissues and possesses multiple functions upon binding to different target proteins. RAGE is a multiligand receptor binding to S100A11 and the interactions at molecular level have not been reported. However, the three-dimensional structure of human S100A11 containing 105 amino acids is still not available for further interaction studies. To determine the solution structure, for the first time we report the (1)H, (15)N and (13)C resonance assignments and protein secondary structure prediction of human S100A11 dimer in complex with calcium using a variety of triple resonance NMR experiments and the chemical shift index (CSI) method, respectively.

Proteomics of human primary osteoarthritic chondrocytes exposed to extremely low-frequency electromagnetic fields (ELF EMFs) and to therapeutic application of musically modulated electromagnetic fields (TAMMEF)

Osteoarthritis (OA) is the most frequent joint disease, characterized by degradation of extracellular matrix and alterations in chondrocyte metabolism. Some authors reported that electromagnetic fields (EMFs) can positively interfere with patients affected by OA, even though the nature of the interaction is still debated. Human primary osteoarthritic chondrocytes isolated from the femoral heads of OA-patients undergoing to total hip replacement, were cultured in vitro and exposed 30 min/day for two weeks to extremely-low-frequency electromagnetic field (ELF) with fixed frequency (100 Hz) and to therapeutic application of musically modulated electromagnetic fields (TAMMEF) with variable frequencies, intensities and waveforms. Sham-exposed (S.E.) cells served as control group. Cell viability was measured at days 2, 7 and 14. After two weeks, cell lysates were processed using a proteomic approach. Chondrocyte exposed to ELF and TAMMEF system demonstrated different viability compared to untreated chondrocytes (S.E.). Proteome analysis of 2D-Electrophoresis and protein identification by mass spectrometry showed different expression of proteins derived from nucleus, cytoplasm and organelles. Function analysis of the identified proteins showed changes in related-proteins metabolism (glyceraldeyde-3-phosphate-dehydrogenase), stress response (Mn-superoxide-dismutase, heat-shock proteins), cytoskeletal regulation (actin), proteinase inhibition (cystatin-B) and inflammation regulatory functions (S100-A10, S100-A11) among the experimental groups (ELF, TAMMEF and S.E.). In conclusion, EMFs do not cause damage to chondrocytes, besides stimulate safely OA-chondrocytes and are responsible of different protein expression among the three groups. Furthermore, protein analysis of OA-chondrocytes treated with ELF and the new TAMMEF systems could be useful to clarify the pathogenetic mechanisms of OA by identifying biomarkers of the disease.

Down-regulation of S100A11, a calcium-binding protein, in human endometrium may cause reproductive failure

BACKGROUND

Low expression levels of S100A11 proteins were demonstrated in the placental villous tissue of patients with early pregnancy loss, and S100A11 is a Ca2+-binding protein that interprets the calcium fluctuations and elicits various cellular responses.

OBJECTIVES

The objective of the study was to determine S100A11 expression in human endometrium and its roles in endometrial receptivity and embryo implantation.

METHODS

S100A11 expression in human endometrium was analyzed using quantitative RT-PCR, Western blot, and immunohistochemical techniques. The effects of S100A11 on embryo implantation were examined using in vivo mouse model, and JAr (a human choriocarcinoma cell line) spheroid attachment assays. The effects of endometrial S100A11 on factors related to endometrial receptivity and immune responses were examined. Using a fluorescence method, we examined the changes in cytosolic Ca2+ and Ca2+ release from intracellular stores in epidermal growth factor (EGF)-treated endometrial cells transfected with or without S100A11 small interfering RNA.

RESULTS

S100A11 was expressed in human endometrium. S100A11 protein levels were significantly lower in endometrium of women with failed pregnancy than that in women with successful pregnancy outcomes. The knockdown of endometrial S100A11 not only reduced embryo implantation rate in mouse but also had adverse effects on the expression of factors related to endometrial receptivity and immune responses in human endometrial cells. Immunofluorescence analysis showed that S100A11 proteins were mainly localized in endoplasmic reticulum. The EGF up-regulated endometrial S100A11 expression and promoted the Ca2+ uptake and release from Ca2+ stores, which was inhibited by the knockdown of S100A11.

CONCLUSIONS

Endometrial S100A11 is a crucial intermediator in EGF-stimulated embryo adhesion, endometrium receptivity, and immunotolerance via affecting Ca2+ uptake and release from intracellular Ca2+ stores. Down-regulation of S100A11 may cause reproductive failure.

Trespassing cancer cells: 'fingerprinting' invasive protrusions reveals metastatic culprits

Metastatic cancer cells produce invasive membrane protrusions called invadopodia and pseudopodia, which play a central role in driving cancer cell dissemination in the body. Malignant cells use these structures to attach to and degrade extracellular matrix proteins, generate force for cell locomotion, and to penetrate the vasculature. Recent work using unique subcellular fractionation methodologies combined with spatial genomic, proteomic, and phosphoproteomic profiling has provided insight into the invadopodiome and pseudopodiome signaling networks that control the protrusion of invasive membranes. Here I highlight how these powerful spatial 'omics' approaches reveal important signatures of metastatic cancer cells and possible new therapeutic targets aimed at treating metastatic disease.

Identification of novel genes selectively expressed in the follicle-associated epithelium from the meta-analysis of transcriptomics data from multiple mouse cell and tissue populations

The follicle-associated epithelium (FAE) overlying the Peyer's patches and the microfold cells (M cells) within it are important sites of antigen transcytosis across the intestinal epithelium. Using a meta-analysis approach, we identified a transcriptional signature that distinguished the FAE from a large collection of mouse cells and tissues. A co-expressed cluster of 21 FAE-specific genes was identified, and the analysis of the transcription factor binding site motifs in their promoter regions indicated that these genes shared an underlying transcriptional programme. This cluster contained known FAE- (Anxa10, Ccl20, Psg18 and Ubd) and M-cell-specific (Gp2) genes, suggesting that the others were novel FAE-specific genes. Some of these novel candidate genes were expressed highly by the FAE and M cells (Calcb, Ces3b, Clca2 and Gjb2), and others only by the FAE (Ascl2, Cftr, Fgf15, Gpr133, Kcna1, Kcnj15, Mycl1, Pgap1 and Rps6kl). We also identified a subset of novel FAE-related genes that were induced in the intestinal epithelium after receptor activator of nuclear factor (NF)-κB ligand stimulation. These included Mfge8 which was specific to FAE enterocytes. This study provides new insight into the FAE transcriptome. Further characterization of the candidate genes identified here will aid the identification of novel regulators of cell function in the FAE.

An efficient expression and purification strategy for the production of S100 proteins in Escherichia coli

S100 proteins belong to a family of small, acidic, EF-hand Ca ( 2+) -binding proteins and have been found to exert both intracellular and extracellular functions in regulation of Ca ( 2+) homeostasis, cytoskeletal dynamics, cell cycle, motility and differentiation. As a result, they have been widely investigated for their association with diseases, such as, neurological diseases, cardiomyopathy, neoplasias and inflammatory diseases. To facilitate further studies of S100 proteins, we reported a simple and efficient method for the expression and purification of human S100A4 and S100A11 proteins in Escherichia coli. Since S100 proteins share many common physical and chemical characteristics, we expect that this approach can be extended to the production of most S100 proteins.

Tissue-based proteomics reveals FXYD3, S100A11 and GSTM3 as novel markers for regional lymph node metastasis in colon cancer

Regional lymph node metastasis negatively affects prognosis in colon cancer patients. The molecular processes leading to regional lymph node metastasis are only partially understood and proteomic markers for metastasis are still scarce. Therefore, a tissue-based proteomic approach was undertaken for identifying proteins associated with regional lymph node metastasis. Two complementary tissue-based proteomic methods have been employed. MALDI imaging was used for identifying small proteins (≤25 kDa) in situ and label-free quantitative proteomics was used for identifying larger proteins. A tissue cohort comprising primary colon tumours without metastasis (UICC II, pN0, n = 21) and with lymph node metastasis (UICC III, pN2, n = 33) was analysed. Subsequent validation of identified proteins was done by immunohistochemical staining on an independent tissue cohort consisting of primary colon tumour specimens (n = 168). MALDI imaging yielded ten discriminating m/z species, and label-free quantitative proteomics 28 proteins. Two MALDI imaging-derived candidate proteins (FXYD3 and S100A11) and one from the label-free quantitative proteomics (GSTM3) were validated on the independent tissue cohort. All three markers correlated significantly with regional lymph node metastasis: FXYD3 (p = 0.0110), S100A11 (p = 0.0071), and GSTM3 (p = 0.0173). FXYD3 and S100A11 were more highly expressed in UICC II patient tumour tissues. GSTM3 was more highly expressed in UICC III patient tumour tissues. By our tissue-based proteomic approach, we could identify a large panel of proteins which are associated with regional lymph node metastasis and which have not been described so far. Here we show that novel markers for regional lymph metastasis can be identified by MALDI imaging or label-free quantitative proteomics and subsequently validated on an independent tissue cohort.

The gene expression analysis of blood reveals S100A11 and AQP9 as potential biomarkers of infective endocarditis

BACKGROUND

The diagnostic and prognostic assessments of infective endocarditis (IE) are challenging. To investigate the host response during IE and to identify potential biomarkers, we determined the circulating gene expression profile using whole genome microarray analysis.

METHODS AND RESULTS

A transcriptomic case-control study was performed on blood samples from patients with native valve IE (n = 39), excluded IE after an initial suspicion (n = 10) at patient's admission, and age-matched healthy controls (n = 10). Whole genome microarray analysis showed that patients with IE exhibited a specific transcriptional program with a predominance of gene categories associated with cell activation as well as innate immune and inflammatory responses. Quantitative real-time RT-PCR performed on a selection of highly modulated genes showed that the expression of the gene encoding S100 calcium binding protein A11 (S100A11) was significantly increased in patients with IE in comparison with controls (P<0.001) and patients with excluded IE (P<0.05). Interestingly, the upregulated expression of the S100A11 gene was more pronounced in staphylococcal IE than in streptococcal IE (P<0.01). These results were confirmed by serum concentrations of the S100A11 protein. Finally, we showed that in patients with IE, the upregulation of the aquaporin-9 gene (AQP9) was significantly associated with the occurrence of acute heart failure (P = 0.02).

CONCLUSIONS

Using transcriptional signatures of blood samples, we identified S100A11 as a potential diagnostic marker of IE, and AQP9 as a potential prognostic factor.

Comparative gene expression study of the chronic exposure to clozapine and haloperidol in rat frontal cortex

Antipsychotic drugs (APDs) are effective in treating some of the positive and negative symptoms of schizophrenia. APDs take time to achieve a therapeutic effect which suggests that changes in gene expression are involved in their efficacy. We hypothesized that there would be altered expression of specific genes associated with the etiology or treatment of schizophrenia in frontal cortex of rats that received chronic treatment with a typical APD (haloperidol) vs. an atypical APD (clozapine). Rats were administered clozapine, haloperidol, or sterile saline intraperitoneally daily for 21days. Frontal cortices from clozapine-, haloperidol-, and saline-treated rats were dissected and subjected to microarray analysis. We observed a significant (1.5 fold, p<0.05) downregulation of 278 genes and upregulation of 73 genes in the clozapine-treated brains vs. controls and downregulation of 451 genes and upregulation of 115 genes in the haloperidol-treated brains vs. control. A total of 146 genes (130 downregulated and 16 upregulated) were significantly altered by both clozapine and haloperidol. These genes were classified by functional groups. qRT-PCR (quantitative real-time polymerase chain reaction) analysis verified the direction and magnitude of change for a group of nine genes significantly altered by clozapine and 11 genes significantly altered by haloperidol. Three genes verified by qRT-PCR were altered by both drugs: Bcl2-like 1 (Bcl2l1), catechol-O-methyltransferase (Comt), and opioid-binding protein/cell adhesion molecule-like (Opcml). Our results show that clozapine and haloperidol cause changes in levels of many important genes that may be involved in etiology and treatment of schizophrenia.