Allopregnanolone suppresses glioblastoma survival through decreasing DPYSL3 and S100A11 expression

Allopregnanolone (allo) is a physiological regulator of neuronal activity that treats multiple neurological disorders. Allo penetrates the blood-brain barrier with very high efficiency, implying that allo can treat CNS-related diseases, including glioblastoma (GBM), which always recurs after standard therapy. Hence, this study aimed to determine whether allo has a therapeutic effect on GBM. We found that allo enhanced temozolomide (TMZ)-suppressed cell survival and proliferation of TMZ-resistant cells. In particular, allo enhanced TMZ-inhibited cell migration and TMZ-induced apoptosis. Additionally, allo strongly induced DNA damage characterized by γH2Ax. Furthermore, quantitative proteomic analysis, iTRAQ, showed that allo significantly decreased the levels of DPYSL3, S100A11, and S100A4, reflecting the poor prognosis of patients with GBM confirmed by differential gene expression and survival analysis. Moreover, single-cell RNA-Seq revealed that S100A11, expressed in malignant cells, oligodendrocytes, and macrophages, was significantly associated with immune cell infiltration. Furthermore, overexpression of DPYSL3 or S100A11 prevented allo-induced cell death. In conclusion, allo suppresses GBM cell survival by decreasing DPYSL3/S100A11 expression and inducing DNA damage.

Adding Perplexity to Rarity: Diffuse S100-Protein and SOX10 Expression in a Molecularly Confirmed PAX7-Positive Primary Cutaneous Ewing Sarcoma

ABSTRACT

Primary cutaneous Ewing sarcoma (EWS) is a very rare neoplasm that shares similar morphologic, immunohistochemical, and molecular features with its osseous counterpart. Herein, we present an extraordinarily rare case of PAX7-positive cutaneous EWS in a 9-year-old girl that was also diffusely positive for SOX10 and S100-protein. Next generation sequencing detected the EWSR1-FLI1 fusion supporting the diagnosis, which was further validated by break-apart EWSR1 fluorescence in situ hybridization. Diffuse S100-protein and SOX10 expression has been reported only in a handful of cases of EWS and may pose significant diagnostic challenges for dermatopathologists. PAX7 is a recently introduced marker, which is highly sensitive for EWS and can potentially have discriminatory power in the differential diagnosis of cutaneous undifferentiated round blue cell tumors.

Nicotine Neurotoxicity Involves Low Wnt1 Signaling in Spinal Locomotor Networks of the Postnatal Rodent Spinal Cord

The postnatal rodent spinal cord in-vitro is a useful model to investigate early pathophysiological changes after injury. While low dose nicotine (1 µM) induces neuroprotection, how higher doses affect spinal networks is unknown. Using spinal preparations of postnatal wild-type Wistar rat and Wnt1Cre2:Rosa26Tom double-transgenic mouse, we studied the effect of nicotine (0.5–10 µM) on locomotor networks in-vitro. Nicotine 10 µM induced motoneuron depolarization, suppressed monosynaptic reflexes, and decreased fictive locomotion in rat spinal cord. Delayed fall in neuronal numbers (including motoneurons) of central and ventral regions emerged without loss of dorsal neurons. Conversely, nicotine (0.5–1 µM) preserved neurons throughout the spinal cord and strongly activated the Wnt1 signaling pathway. High-dose nicotine enhanced expression of S100 and GFAP in astrocytes indicating a stress response. Excitotoxicity induced by kainate was contrasted by nicotine (10 µM) in the dorsal area and persisted in central and ventral regions with no change in basal Wnt signaling. When combining nicotine with kainate, the activation of Wnt1 was reduced compared to kainate/sham. The present results suggest that high dose nicotine was neurotoxic to central and ventral spinal neurons as the neuroprotective role of Wnt signaling became attenuated. This also corroborates the risk of cigarette smoking for the foetus/newborn since tobacco contains nicotine.

The Role of CK7, S100A1, and CD82 (KAI1) Expression in the Differential Diagnosis of Chromophobe Renal Cell Carcinoma and Renal Oncocytoma

Renal oncocytoma is a benign renal tumor originated from intercalated cells of collecting ducts like chromophobe renal cell carcinoma (RCC). The differential diagnosis of these 2 tumors is important because while they are histologically and cytologically similar, they show different biological behavior. For the differential diagnosis, several immunohistochemical markers have been investigated. But, differential diagnostic challenges remain and the identification of additional markers is needed. Cytokeratin 7 (CK7) is one of ductal-type keratins, which is expressed in tumors of breast, pancreas, lung, thyroid, ovary, endometrium, urinary bladder, and the kidney. S100A1 is the first defined member of the calcium-binding S100 protein family and it organizes several cellular functions including cell cycle progression and cell differentiation.CD82 is a tetraspanin membrane protein, which functions as a metastasis supressor. In this study, we immunohistochemically investigated the expressions of CK7, S100A1, and CD82 in 30 chromophobe RCC (23 classic and 7 eosinophilic variant) and 19 oncocytomas. When these markers were evaluated separately and together, their expressions in chromophobe RCC and renal oncocytoma show statistically significant difference (P<0.001). Similar statistically significant results were also seen between eosinophilic chromophobe RCC and oncocytoma (P<0.001). For both classic and eosinophilic-variant chromophobe RCCs, CK7+/S100A1-/CD82+ profile being the most common. In oncocytomas, the most frequently observed profile was CK7-/S100A1+/CD82-. Our results showed that the application of a panel consisting of CK7, S100A1, and CD82 may provide accurate categorization of the tumors in difficult cases.

Regulation of S100A10 Gene Expression

S100A10, a member of the S100 family of Ca²⁺-binding proteins, is a widely distributed protein involved in many cellular and extracellular processes. The best recognized role of S100A10 is the regulation, via interaction with annexin A2, of plasminogen conversion to plasmin. Plasmin, together with other proteases, induces degradation of the extracellular matrix (ECM), which is an important step in tumor progression. Additionally, S100A10 interacts with 5-hydroxytryptamine 1B (5-HT1B) receptor, which influences neurotransmitter binding and, through that, depressive symptoms. Taking this into account, it is evident that S100A10 expression in the cell should be under strict control. In this work, we summarize available literature data concerning the physiological stimuli and transcription factors that influence S100A10 expression. We also present our original results showing for the first time regulation of S100A10 expression by grainyhead-like 2 transcription factor (GRHL2). By applying in silico analysis, we have found two highly conserved GRHL2 binding sites in the 1st intron of the gene encoding S100A10 protein. Using chromatin immunoprecipitation (ChIP) and luciferase assays, we have shown that GRHL2 directly binds to these sites and that this DNA region can affect transcription of S100A10.

Tumor innervation and clinical outcome in pancreatic cancer

Pancreatic cancer is a highly aggressive malignancy characterized by poor survival, recurrence after surgery and resistance to therapy. Nerves infiltrate the microenvironment of pancreatic cancers and contribute to tumor progression, however the clinicopathological significance of tumor innervation is unclear. In this study, the presence of nerves and their cross-sectional size were quantified by immunohistochemistry for the neuronal markers S-100, PGP9.5 and GAP-43 in a series of 99 pancreatic cancer cases versus 71 normal adjacent pancreatic tissues. A trend was observed between the presence of nerves in the tumor microenvironment of pancreatic cancer and worse overall patient survival (HR = 1.8, 95% CI 0.77-4.28, p = 0.08). The size of nerves, as measured by cross-sectional area, were significantly higher in pancreatic cancer than in the normal adjacent tissue (p = 0.002) and larger nerves were directly associated with worse patient survival (HR = 0.41, 95% CI 0.19-0.87, p = 0.04). In conclusion, this study suggests that the presence and size of nerves within the pancreatic cancer microenvironment are associated with tumor aggressiveness.

Actinic keratosis and surrounding skin exhibit changes in corneocyte surface topography and decreased levels of filaggrin degradation products

Actinic keratosis (AK) is a frequent premalignant skin lesion mainly caused by chronic sun exposure. AK lesions are often surrounded by invisible, subclinical alterations, called field of cancerization (FoC). Definition of FoC is of importance for therapy management; however, the criteria and non-invasive tools to characterize FoC are lacking. Atomic force microscopy (AFM) proved to be a suitable tool for detection of changes in the corneocyte surface topography in inflammatory skin diseases, which share similar clinical features with AK such as hyper- and parakeratosis. Therefore, in this study we applied AFM to investigate AK and surrounding skin obtained by non-invasive collection of the stratum corneum (SC) with adhesive tapes. Furthermore, we determined degradation products of structural protein filaggrin (natural moisturizing factor, NMF), which previously showed association with the changes in corneocyte surface topography. Ten patients with multiple AK on the face were recruited from the outpatient clinic. SC samples were collected from the AK lesion, skin sites adjacent to the AK, 5 cm from the AK and retroauricular area. Corneocyte surface topography was determined by AFM, and NMF by liquid chromatography. The AK lesion showed alterations of the corneocyte surface topography characterized by an increased number of nanosize protrusions, which gradually decreased with the distance from the lesion. NMF levels show an inverse pattern. Atomic force microscopy showed to be a suitable tool to detect changes in the corneocyte surface topography on the AK lesion and surrounding skin in a non-invasive manner.

The single intravenous administration of methylene blue after traumatic brain injury diminishes neurological deficit, blood-brain barrier disruption and decrease in the expression of S100 protein in rats

The protective effect of methylene blue (MB) was investigated on the model of focal one-sided traumatic brain injury (TBI) of the sensorimotor cortex region from 1 to 7 days after the injury. TBI caused a reliable disruption of the functions of the limbs contralateral to injury focus, an increase in the expression of S100 protein and blood-brain barrier (BBB) permeability in the ipsilateral hemisphere. The single intravenous injection of MB (1 mg/kg body weight) 30 min after TBI significantly reduced the limb function impairment as well as a TBI-induced increase in the expression of inflammatory marker S100 protein, and BBB permeability. When modeling inflammation in vitro, MB was found to protect cultured neurons from the toxic effects of lipopolysaccharide. In conclusion, the preservation of blood-brain barrier and a decrease in the expression of S100 protein may be an important mechanism by means of which MB improves neurological outcome. Our data demonstrate that MB can be a very promising pharmacological compound with neuroprotective properties for TBI treatment.

Immunohistochemical expression patterns of S100, synaptophysin, chromogranin A and neuron specific enolase in predicting malignant behaviour in paragangliomas

PURPOSE

The purpose of this study was to evaluate the role of immunohistochemical markers in the prediction of malignancy in paragangliomas.

METHODS

Our institute's patient records between 1990-2012 were retrieved in order to identify patients who were treated for paragangliomas. Size and location of the tumour, existence of concurrent metastatic disease, patient demographics and survival were recorded. Haematoxylin-eosin stained slides were reviewed and all tumours were stained specifically for neuron specific enolase (NSE), chromogranin, synaptophysin and S100 protein positivity. Positivity and expression patterns of the above markers were evaluated and compared between malignant and benign tumours. Malignant behaviour was defined when patient had concurrent or subsequent lymph node involvement, local recurrence and/or metastases.

RESULTS

A total of 22 patients with a diagnosis of paraganglioma were treated in our institutes. Female to male ratio was 1.75: 1. The mean age was 43.5 and 51.6 years for women and men, respectively. In 5 patients the tumors had malignant clinical behavior. Their mean size was 3.65 cm for benign and 4.56 cm for malignant neoplasms. NSE expression was diffuse in 47.1% and 0% for benign and malignant tumors, respectively (p=0.10). S100 expression in the periphery of the tumour was typical in 88.2% and 0% for benign and malignant tumors, respectively (p<0.001).

CONCLUSION

Immunohistochemical profile from the combination of NSE, synaptophysin chromogranin and S100 staining patterns can serve as a cheap and valuable tool for correctly distinguishing between malignant and benign paragangliomas with high diagnostic accuracy.

Loss of Conventional Melanocytic Markers in Malignant Melanoma and Lymph Node Metastasis; an Uncommon but Dangerous Pitfall

Although malignant melanomas exhibit a wide range of immunophenotypes, concurrent loss of all 3 conventional melanocytic markers (S-100, Melan-A, and HMB-45) is relatively rare. We report a case of primary malignant melanoma with lymph node metastasis, both exhibiting loss of immunoreactivity for conventional melanocytic markers, while aberrantly expressing epithelial antigenicity (pancytokeratin, CAM 5.2).

Comprehensive protein profiling of synovial fluid in osteoarthritis following protein equalization

OBJECTIVE

The aim of the study was to characterise the protein complement of synovial fluid (SF) in health and osteoarthritis (OA) using liquid chromatography mass spectrometry (LC-MS/MS) following peptide-based depletion of high abundance proteins.

DESIGN

SF was used from nine normal and nine OA Thoroughbred horses. Samples were analysed with LC-MS/MS using a NanoAcquity™ LC coupled to an LTQ Orbitrap Velos. In order to enrich the lower-abundance protein fractions protein equalisation was first undertaken using ProteoMiner™. Progenesis-QI™ LC-MS software was used for label-free quantification. In addition immunohistochemistry, western blotting and mRNA expression analysis was undertaken on selected joint tissues.

RESULTS

The number of protein identifications was increased by 33% in the ProteoMiner™ treated SF compared to undepleted SF. A total of 764 proteins (462 with≥2 significant peptides) were identified in SF. A subset of 10 proteins were identified which were differentially expressed in OA SF. S100-A10, a calcium binding protein was upregulated in OA and validated with western blotting and immunohistochemistry. Several new OA specific peptide fragments (neopeptides) were identified.

CONCLUSION

The protein equalisation method compressed the dynamic range of the synovial proteins identifying the most comprehensive SF proteome to date. A number of proteins were identified for the first time in SF which may be involved in the pathogenesis of OA. We identified a distinct set of proteins and neopeptides that may act as potential biomarkers to distinguish between normal and OA joints.

Expression of S100 family proteins in neonatal rats with sepsis and its significance

OBJECTIVE

This study aims to study the expression changes of S100 family proteins in neonatal rats with sepsis and investigate the effect and significance of S100 family proteins in pathogenesis and development of sepsis.

METHODS

The functions of S100 family proteins were analyzed with bioinformatics. The immune-associated proteins were chosen as the candidate proteins. Twenty neonatal SPF SD rats were randomly divided into two groups: sepsis model group and control group. The liver sample was stained with HE to evaluate the establishment of sepsis model. The expression amount of proinflammatory factor IL-1, IL-6 and TNF-α was detected with ELISA. The expression changes of S100A8, S100A9, S100A11 and S100A12 in sepsis model rats were detected with real-time PCR and Western blotting. After shRNA plasmid was transfected into THP-1 cells and the expression of S100A12 was silenced, the expression changes of proinflammatory factor IL-1, IL-6 and TNF-α in LPS-induced inflammation were studied in order to investigate the S100A12 mediated inflammatory process.

RESULTS

IL-1, IL-6 and TNF-α in the serum of rats with sepsis induced by LPS were 55.79 ± 3.80 ng/l, 48.76 ± 1.03 ng/l and 29.98 ± 2.27 ng/l respectively. S100A8, S100A9, S100A11 and S100A12 detected with real-time PCR in sepsis model group were 14.4 ± 1.37, 10.23 ± 1.81, 5.5 ± 1.64 and 9.97 ± 1.82 respectively. Compared with the control group, S100A8, S100A9, and S100A12 were significantly up-regulated. The shRNA silenced the expression of S100A12 which reduced the expression of proinflammatory factors after LPS stimulated the cells (P < 0.05).

CONCLUSION

Compared with the control group, S100A8, S100A9, and S100A12 were significantly up-regulated in rat sepsis model group. After the expression of S100A12 in propylene glycol monomethyl ether acetate (PMA) induced human macrophages was silenced, the expression of proinflammatory factor IL-1, IL-6 and TNF-α was down-regulated.

S100A4 promotes liver fibrosis via activation of hepatic stellate cells

BACKGROUND & AIMS

S100A4 has been linked to the fibrosis of several organs due to its role as a fibroblast-specific marker. However, the role of S100A4 itself in the development of fibrosis has not been much investigated. Here, we determined whether S100A4 regulates liver fibrogenesis and examined its mechanism by focusing on the activation of hepatic stellate cells (HSCs).

METHODS

S100A4 deficient mice were used to determine the role of S100A4 in liver fibrogenesis. The effect of S100A4 on HSC activation was estimated by using primary mouse HSCs and the human HSC cell line LX-2. Serum levels of S100A4 in cirrhotic patients were determined by ELISA.

RESULTS

S100A4 was found to be secreted by a subpopulation of macrophages and to promote the development of liver fibrosis. It accumulated in the liver during the progression of liver fibrosis and activated HSCs in mice. In vitro studies demonstrated that S100A4 induced the overexpression of alpha-smooth muscle actin through c-Myb in HSCs. Both, the selective depletion of S100A4-expressing cells and knockdown of S100A4 in the liver by RNA interference, resulted in a reduction of liver fibrosis following injury. Importantly, increased S100A4 levels in both the liver tissue and serum correlated positively with liver fibrosis in humans.

CONCLUSIONS

S100A4 promotes liver fibrosis by activating HSCs, which may represent a potential target for anti-fibrotic therapies.

RLN2 regulates in vitro invasion and viability of osteosarcoma MG-63 cells via S100A4/MMP-9 signal

OBJECTIVE

Relaxin-2 (RLN2) increases cell migration, invasiveness and proliferation in vitro of osteosarcoma cells, but the molecular mechanisms of this action are still unknown. In the present study, we identified S100A4 /MMP-9 signaling as a major mediator of the actions of RLN2 in osteosarcoma cells in vitro.

MATERIALS AND METHODS

We have established stable transfectants of osteosarcoma MG-63 cells using small interfering RNA (siRNA) targeting RLN2. The stable transfectants (MG-63/RLN2 siRNA cells) were treated with 20 mM BB94 (a kind of MMP-9 activator) or 100 mM recombinant Human RLN2 (B-29/A-24) for 24 hs or transfected with S100A4 cDNA plasmid for 48 hrs or MMP-9 siRNA for 48 hrs then treated 100 mM recombinant Human RLN2 (B-29/A-24). Western blot assay was used to detect RLN2, S100A4 and MMP-9 expression. Matrigel invasion assay and wound healing assay was used to detect invasion in vitro. MTT was used to detect cell viability.

RESULTS

Knockdown of RLN2 using small interfering RNA decreases S100A4 and MMP-9 expression and inhibits invasion and cell viability in vitro. in MG-63 cells. Treatment with 100 mM recombinant Human RLN2 (B-29/A-24) for 24 hrs in MG-63/ RLN2 siRNA cells increases S100A4 and MMP-9 expression, and increases the invasion and cell viability in vitro in MG-63 cells. Transfection with S100A4 cDNA plasmid in MG-63/RLN2 siRNA cells for 48 hrs increases MMP-9 expression, and increase the invasion and cell viability of MG-63/RLN2 siRNA cells. Treatment with 20 mM BB94 (MMP-9 activator) for 24 hrs in MG-63/RLN2 siRNA cells increases MMP-9 expression, and increases the invasion and cell viability in vitro. in MG-63 cells.

CONCLUSIONS

Our results indicate that RLN2 regulats cell migration, invasiveness and proliferation of osteosarcoma cells in vitro, which may be mediated through S100A4/MMP-9 signaling.

Knockdown of S100A4 chemosensitizes human laryngeal carcinoma cells in vitro through inhibition of Slug

OBJECTIVE

S100A4 and Slug are known to be closely involved in resistance to chemotherapy. Furthermore, Slug signal was regulated by S100A4. Targeted therapy reducing S100A4 expression and Slug pathway activity may overcome the chemoresistance of human cancers. We hypothesized that over-expression of S100A4 and Slug was associated with the resistance to cisplatin of laryngeal carcinoma Hep-2 cells. We explored whether S100A4 silencing inhibited Slug, resulting in sensitization of laryngeal carcinoma Hep-2 cells to cisplatin.

MATERIALS AND METHODS

We investigated the effects of S100A4 and Slug silencing by siRNA transfection on chemosensitivity to cisplatin (DDP) in Hep-2 cells in vitro. In order to confirm the correlation between S100A4 and Slug signals, siRNA transfected Hep-2 cells were over-expressed by pSlug transfection, then explored the effect of S100A4 silencing on chemosensitivity to cisplatin (DDP) in Hep-2 cells in vitro. Real-time RT-PCR and Western blotting confirmed the presence of S100A4 mRNA, Slug mRNA and proteins in Hep-2 cells.

RESULTS

We found that resistance or insensitivity of Hep-2 cells to cisplatin might be associated with S100A4 and Slug expression. Knockdown of S100A4 and Slug markedly enhanced the cisplatin-induced suppression of Hep-2 cell growth and increased apoptosis. Knockdown of S100A4 may significantly reduce the levels of S100A4 mRNA, Slug mRNA and proteins, in cisplatin-treated Hep-2 cells. Re-expression of Slug in S100A4 siRNA transfected Hep-2 cells restored the cisplatin resistance in the Hep-2 cells.

CONCLUSIONS

Overexpression of S100A4 may be associated with the resistance to cisplatin of laryngeal carcinoma Hep-2 cells. Knockdown of S100A4 enhances the sensitivity to cisplatin of laryngeal carcinoma cells via inhibition of Slug expression.

Prognostic significance of relaxin-2 and S100A4 expression in osteosarcoma

OBJECTIVE

Relaxin-2 (RLN2) and calcium-binding protein S100A4 was overexpressed in many cancers. Experimental evidence indicated enhanced tumor cell invasion by RLN2 involves the upregulation of S100A4. However, the relationship between them in cancers is not clear. In the present study, we investigate the expression of relaxin-2 protein and calcium-binding protein S100A4 in osteosarcoma by immunohistochemistry assay and their relationship to the clinicopathological parameters and prognosis of osteosarcoma (OS).

MATERIALS AND METHODS

Expression status of RLN2 and S100A4 was examined in 130 surgical specimens of primary OS by immunohistochemistry. Correlation between the expression of RLN2 and S100A4 and clinicopathological parameters was analyzed.

RESULTS

78 of 130 (60%) specimens of primary OS were positive for RLN2. 67 of 130 (51.5%) specimens showed positive expression of S100A4. The positive correlation between RLN2 and S100A4 expression was significant in cancer tissues (p = 0.02). RLN2 and S100A4 expression in osteosarcoma tissues was significantly higher than that in corresponding noncancerous bone tissues both p = 0.000). In addition, high RLN2 and S100A4 expression more frequently occurred in osteosarcoma tissues with advanced clinical stage (both p < 0.05) and positive distant metastasis (both p < 0.05). Moreover, osteosarcoma patients with high RLN2 and S100A4 expression had significantly shorter overall survival and disease-free survival (both p < 0.001) when compared with patients with the low expression of RLN2 and S100A4. On Cox multivariate analysis, RLN2 and S100A4 overexpression, distant metastasis were the independent and significant prognostic factor to predict poor overall survival and disease-free survival.

CONCLUSIONS

We, therefore, suggested overexpression of RLN2 and S100A4 might be related to the prediction of metastasis potency and poor prognosis for osteosarcoma patients. Detection of RLN2 and S100A4 might be useful in evaluating the outcome of patients with OS.

Estrogen suppresses adipogenesis by inhibiting S100A16 expression

The aim of this study is to determine the effects of E2 on metabolic syndrome and the molecular mechanisms involving S100A16. Ovariectomized (OVX) rat models and mouse embryonic fibroblasts cell models were used. E2 loss in OVX rats induced body weight gain and central abdominal fat accumulation, which were ameliorated by E2 treatment under chow and high-fat diet (HFD) conditions. E2 decreased the expression of the adipocyte marker genes PPARγ, aP2, C/EBPα, and S100A16. E2 inhibited adipogenesis. Overexpression of S100A16 reversed the E2-induced adipogenesis effect. A luciferase assay showed that E2 inhibited the expression of S100A16. E2 treatment decreased body weight gain and central abdominal fat accumulation under both chow and HFD conditions. Also, E2 suppressed adipogenesis by inhibiting S100A16 expression.

Proteomics analysis of melanoma metastases: association between S100A13 expression and chemotherapy resistance

BACKGROUND

Disseminated cutaneous malignant melanoma (CMM) is commonly unresponsive to standard chemotherapies, and there are as yet no predictive markers of therapy response.

METHODS

In the present study we collected fresh-frozen pretreatment lymph-node metastasis samples (n=14) from melanoma patients with differential response to dacarbazine (DTIC) or temozolomide (TMZ) chemotherapy, to identify proteins with an impact on treatment response. We performed quantitative protein profiling using tandem mass spectrometry and compared the proteome differences between responders (R) and non-responders (NR), matched for age, gender and histopathological type of CMM.

RESULTS

Biological pathway analyses showed several signalling pathways differing between R vs NR, including Rho signalling. Gene expression profiling data was available for a subset of the samples, and the results were compared with the proteomics data. Four proteins with differential expression between R and NR were selected for technical validation by immunoblotting (ISYNA1, F13A1, CSTB and S100A13), and CSTB and S100A13 were further validated on a larger sample set by immunohistochemistry (n=48). The calcium binding protein S100A13 was found to be significantly overexpressed in NR compared with R in all analyses performed.

CONCLUSIONS

Our results suggest that S100A13 is involved in CMM resistance to DTIC/TMZ.

Blocking TGF-β inhibits breast cancer cell invasiveness via ERK/S100A4 signal

OBJECTIVE

Targeted down-regulation of TGF-β expression inhibits invasion and metastasis in breast cancer cells. However, the mechanism that TGF-β functions by remains largely unknown. In the present study we report the mechanism of ERK1/2 dependant S100A4 regulation by TGF-β and its possible role in TGF-β-mediated tumour invasion in vitro.

MATERIALS AND METHODS

Small interfering RNA targeting TGF-β1 (TGF-β1 siRNA) were stably transfected into the breast cancer cell line MDA231. The TGF-β1 siRNA/9MDA231 cells were then treated with TGF-β1 (5 ng/ml) or treated with PD98059 (25 μM) or transfected into S100A4 siRNA before TGF-β1 treatment. The cells were used in several in vitro analyses, including migration, invasion, angiogenesis, and signaling assays. A wound-healing assay was used to determine migration of the cells in culture and a Boyden chamber transwell assay was used for invasion. In vitro angiogenesis studies using conditioned medium in HMEC-1 cells.

RESULTS

Inhibition of TGF-β1 expression by TGF-β1 siRNA transfection in MDA231 cells showed significant decrease migration, invasion and angiogenesis in vitro. TGF-β1 siRNA/MDA231 cells treated with 5 ng/ml TGF-β1 for 24 hs restored the invasive ability of TGF-β1 siRNA/MDA231 cells. TGF-β1 treatment could not increase migration, invasion and angiogenesis in TGF-β1 siRNA/MDA231 cells when treated with 25 μM PD98059 or transfected with S100A4 siRNA before TGF-β1 treatment. Analysis of TGF-β1 signaling pathways showed a decrease in p-ERK1/2 activation and an decrease in S100A4 expression. Interestingly, TGF-β1 regulated S100A4 via ERK1/2 signalling.

CONCLUSIONS

Our findings showed that blocking TGF-β inhibits breast cancer cell invasiveness, migration and angiogenesis via ERK/S100A4 signalling. Therapies targeting the TGF-β signaling pathway may be more effective to prevent progression in breast cancer.

Silencing of S100A4, a metastasis-associated protein, in endothelial cells inhibits tumor angiogenesis and growth

Endothelial cells express S100A4, a metastasis-associated protein, but its role in angiogenesis remains to be elucidated. Here we show that knockdown of S100A4 in mouse endothelial MSS31 cells by murine specific small interference RNA (mS100A4 siRNA) markedly suppressed capillary-like tube formation in vitro, in early stage after the treatment, along with down- and up-regulation of some of the pro-angiogenic and anti-angiogenic gene expression, respectively. Of particular note is that intra-tumor administration of the mS100A4 siRNA in a human prostate cancer xenograft significantly reduced tumor vascularity and resulted in the inhibition of tumor growth. These findings show that S100A4 in endothelial cells is involved in tube formation, and suggest its potential as a molecular target for inhibiting tumor angiogenesis, which warrants further development of endothelial S100A4-based strategies for cancer treatment.

Comparative genomic hybridization in a case of melanoma that loses expression of S100, HMB45, Melan A and tyrosinase in metastasis

We recently reported three cases of metastatic melanoma that does not express S100, HMB45, Melan A and Tyrosinase. A concurrent cutaneous scalp primary melanoma was identified later in one of the cases, which showed strong expression of these markers. The difference in immunophenotype between the primary melanoma and its metastasis in the parotid gland in this case raised the question of the biological significance of the expression of these markers and metastatic potential. To address this question, we utilized microarray comparative genomic hybridization (aCGH) to compare the cytogenetic features between the primary and metastatic melanoma. We observed chromosomal gains including 6p, entire chromosome 7, and 8q11.1-q24.3 in both primary and metastatic tumors. However, the metastatic lesion showed unique additional copy of chromosomal 7q, and loss of chromosome 9p24.3-q13 and chromosome 4, which included Melan A encoding gene region in 9p24.1. The above findings suggest the unique cytogenetic changes in the parotid lesion are most likely related to the metastatic behavior, as well as responsible for loss of multiple melanocytic marker expression in the metastatic melanoma for this case.

MicroRNA-138 regulates hypoxia-induced endothelial cell dysfunction by targeting S100A1

The Ca²⁺ sensor S100A1 is essential for proper endothelial cell (EC) nitric oxide (NO) synthase (eNOS) activation. S100A1 levels are greatly reduced in primary human microvascular ECs subjected to hypoxia, rendering them dysfunctional. However mechanisms that regulate S100A1 levels in ECs are unknown. Here we show that ECs transfected with a S100A1–3′ untranslated region (UTR) luciferase reporter construct display significantly reduced gene expression when subjected to low oxygen levels or chemical hypoxia. Bioinformatic analysis suggested that microRNA -138 (MiR-138) could target the 3′UTR of S100A1. Patients with critical limb ischemia (CLI) or mice subjected to femoral artery resection (FAR) displayed increased MiR-138 levels and decreased S100A1 protein expression. Consistent with this finding, hypoxia greatly increased MiR-138 levels in ECs, but not in skeletal muscle C2C12 myoblasts or differentiated myotubes or primary human vascular smooth muscle cells. Transfection of a MiR-138 mimic into ECs reduced S100A1–3 ‘UTR reporter gene expression, while transfection of an anti MiR-138 prevented the hypoxia-induced downregulation of the reporter gene. Deletion of the 22 nucleotide putative MiR-138 target site abolished the hypoxia-induced loss of reporter gene expression. Knockdown of Hif1-α mediated by siRNA prevented loss of hypoxia-induced reporter gene expression. Conversely, specific activation of Hif1-α by a selective prolyl-hydroxylase inhibitor (IOX2) reduced reporter gene expression even in the absence of hypoxia. Finally, primary ECs transfected with a MiR-138 mimic displayed reduced tube formation when plated onto Matrigel matrix and expressed less NO when stimulated with VEGF. These effects were reversed by gene transfer of S100A1 using recombinant adenovirus. We conclude that hypoxia-induced MiR-138 is an essential mediator of EC dysfunction via its ability to target the 3′UTR of S100A1.

Balloon cell melanoma of the anal canal: a wolf in sheep's clothing?

Balloon cell melanoma (BCM) is a rare histologic variant of cutaneous malignant melanoma with exceptional reports of occurrences at non-cutaneous sites. Herein we present a case of primary amelanotic BCM of anal canal, a heretofore undescribed location. Histologically, the tumor was characterized by sheets of pale cells that bore striking resemblance to foamy macrophages. Presence of rare atypical mitoses confirmed the malignant nature of the cells. Neoplastic cells were immunoreactive for S100, Melan-A, and focally for HMB-45 while were negative for myogenic, gastrointestinal stromal tumor, epithelial and neuroendocrine markers. Resemblance to foamy macrophages, bland cytology and absence of pigment imparts this tumor a deceptively benign histological appearance making it prone to diagnostic pitfalls. Awareness of this rare entity and judicious employment of immunohistochemistry is imperative in segregating it from its diverse mimics.

Receptor for advanced glycation end products regulates adipocyte hypertrophy and insulin sensitivity in mice: involvement of Toll-like receptor 2

Receptor for advanced glycation end products (RAGE) has been shown to be involved in adiposity as well as atherosclerosis even in nondiabetic conditions. In this study, we examined mechanisms underlying how RAGE regulates adiposity and insulin sensitivity. RAGE overexpression in 3T3-L1 preadipocytes using adenoviral gene transfer accelerated adipocyte hypertrophy, whereas inhibitions of RAGE by small interfering RNA significantly decrease adipocyte hypertrophy. Furthermore, double knockdown of high mobility group box-1 and S100b, both of which are RAGE ligands endogenously expressed in 3T3-L1 cells, also canceled RAGE-medicated adipocyte hypertrophy, implicating a fundamental role of ligands-RAGE ligation. Adipocyte hypertrophy induced by RAGE overexpression is associated with suppression of glucose transporter type 4 and adiponectin mRNA expression, attenuated insulin-stimulated glucose uptake, and insulin-stimulated signaling. Toll-like receptor (Tlr)2 mRNA, but not Tlr4 mRNA, is rapidly upregulated by RAGE overexpression, and inhibition of Tlr2 almost completely abrogates RAGE-mediated adipocyte hypertrophy. Finally, RAGE(-/-) mice exhibited significantly less body weight, epididymal fat weight, epididymal adipocyte size, higher serum adiponectin levels, and higher insulin sensitivity than wild-type mice. RAGE deficiency is associated with early suppression of Tlr2 mRNA expression in adipose tissues. Thus, RAGE appears to be involved in mouse adipocyte hypertrophy and insulin sensitivity, whereas Tlr2 regulation may partly play a role.

Post-operative recurrent trachomatous trichiasis is associated with increased conjunctival expression of S100A7 (psoriasin)

Background

Surgery for trachomatous trichiasis (TT) is a key component of the SAFE Strategy for trachoma control. Unfortunately, recurrent TT following surgery is common, probably due to various surgical and disease factors. To develop strategies to reduce recurrence rates it is necessary to understand its pathological basis. In this study we investigated the relationship between recurrent trichiasis and the expression of various cytokines and fibrogenic genes during a two-year follow-up period.

Methodology/Principal Findings

Individuals undergoing surgery for TT were examined at baseline (pre-operative), 6, 12, 18 and 24 months. Conjunctival swab samples were collected from the tarsal conjunctiva for RNA isolation on each occasion. Individuals who developed recurrent TT with at least 3 lashes touching the eye on one or more occasion were designated “cases” and an equal number of “controls” were randomly selected from those without recurrent TT, frequency matched for age and baseline TT severity. The expression of the following genes was measured by quantitative RT-PCR: S100A7, IL1B, CXCL5, TNFA, NOS2A, CTGF, MMP7, MMP9 and MMP12. Thirteen hundred individuals were enrolled and underwent surgery. By two years 122 had developed recurrent TT with at least 3 lashes touching the eye. Recurrent TT was consistently associated across multiple time points with about a 2-fold increase in S100A7 expression (p = 0.008). Clinically visible conjunctival inflammation was associated with increased S100A7, IL1B, CXCL5, MMP9 and MMP12 expression.

Conclusions/Significance

Increased S100A7 expression was associated with trachomatous conjunctival scarring and may be linked to the pathophysiology of recurrent TT. S100A7 expression could be a potential biomarker for this disease process. As part of the epithelial innate immune response S100A7 has multiple actions, potentially contributing to a chronic pro-inflammatory response, which may lead to ongoing tissue damage and increased scarring.

Trachoma causes blindness through corneal damage from in-turned eyelashes (trachomatous trichiasis [TT]). Trichiasis is treated surgically to correct the anatomical abnormality. Unfortunately, TT frequently returns following surgery, which again puts the person at risk of sight loss. Recurrent trichiasis is multifactorial. We investigated the possible role of various immuno-fibrogenic factors. To do this we operated on 1300 people with TT and followed them up every six months for a two-year period. On each occasion a conjunctival swab was collected for human gene expression analysis. We measured various factors that are thought to be important in inflammation and scarring diseases. The gene expression profile of people who developed recurrent TT was compared to a sample of those that did not have a recurrence. Recurrent TT was associated with increased expression of psoriasin (S100A7) before surgery and on multiple occasions during a two-year follow-up period. S100A7 is able to promote inflammation and may contribute to the development of the scarring process in trachoma.

Electrical stimulation to conductive scaffold promotes axonal regeneration and remyelination in a rat model of large nerve defect

Background

Electrical stimulation (ES) has been shown to promote nerve regeneration when it was applied to the proximal nerve stump. However, the possible beneficial effect of establishing a local electrical environment between a large nerve defect on nerve regeneration has not been reported in previous studies. The present study attempted to establish a local electrical environment between a large nerve defect, and examined its effect on nerve regeneration and functional recovery.

Methodology/Findings

In the present study, a conductive scaffold was constructed and used to bridge a 15 mm sciatic nerve defect in rats, and intermittent ES (3 V, 20 Hz) was applied to the conductive scaffold to establish an electrical environment at the site of nerve defect. Nerve regeneration and functional recovery were examined after nerve injury repair and ES. We found that axonal regeneration and remyelination of the regenerated axons were significantly enhanced by ES which was applied to conductive scaffold. In addition, both motor and sensory functional recovery was significantly improved and muscle atrophy was partially reversed by ES localized at the conductive scaffold. Further investigations showed that the expression of S-100, BDNF (brain-derived neurotrophic factor), P0 and Par-3 was significantly up-regulated by ES at the conductive scaffold.

Conclusions/Significance

Establishing an electrical environment with ES localized at the conductive scaffold is capable of accelerating nerve regeneration and promoting functional recovery in a 15 mm nerve defect in rats. The findings provide new directions for exploring regenerative approaches to achieve better functional recovery in the treatment of large nerve defect.

[Disseminated juvenile xanthogranuloma expressing protein S100]

BACKGROUND

Juvenile xanthogranuloma (JXG) is a form of self-healing non-Langerhans histiocytosis. We report a new case of disseminated JXG without visceral involvement but with positive immunostaining of the majority of histiocytes for protein S100.

PATIENTS AND METHODS

A 6-month-old male infant was admitted to our department in January 2010 for congenital nodular lesions of varying size, shape and appearance. The remainder of the dermatological and physical examination was unremarkable. The diagnosis of disseminated JXG, strongly suggested clinically, was confirmed by a skin biopsy. However, immunohistochemistry was confusing, with positivity for protein S100. The lesions regressed spontaneously.

DISCUSSION

The aim of this case report is to highlight the lack of any forced association between alarming skin lesions of eruptive JXG and systemic involvement. The distinguishing feature of our case is the positive immunostaining for protein S100 in the histological section, which although rare in XJG, does not cast doubt on the diagnosis of non-Langerhans histiocytosis providing the clinical presentation is typical. Therapeutic abstention is the rule.

Receptor for advanced glycation endproducts (RAGE) deficiency protects against MPTP toxicity

Parkinson's disease (PD) is a common neurodegenerative disorder of unknown pathogenesis characterized by the loss of nigrostriatal dopaminergic neurons. Oxidative stress, microglial activation and inflammatory responses seem to contribute to the pathogenesis. The receptor for advanced glycation endproducts (RAGE) is a multiligand receptor of the immunoglobulin superfamily of cell surface molecules. The formation of advanced glycation end products (AGEs), the first ligand of RAGE identified, requires a complex series of reactions including nonenzymatic glycation and free radical reactions involving superoxide-radicals and hydrogen peroxide. Binding of RAGE ligands results in activation of nuclear factor-kappaB (NF-κB). We show that RAGE ablation protected nigral dopaminergic neurons against cell death induced by the neurotoxin MPTP that mimics most features of PD. In RAGE-deficient mice the translocation of the NF-κB subunit p65 to the nucleus, in dopaminergic neurons and glial cells was inhibited suggesting that RAGE involves the activation of NF-κB. The mRNA level of S100, one of the ligands of RAGE, was increased after MPTP treatment. The dopaminergic neurons treated with MPP(+) and S100 protein showed increased levels of apoptotic cell death, which was attenuated in RAGE-deficient mice. Our results suggest that activation of RAGE contributes to MPTP/MPP(+)-induced death of dopaminergic neurons that may be mediated by NF-κB activation.

[S-100 protein expression in the different brain structures of fetus and newborns suffering from ventriculomegalia and hydrocephaly]

Parenchyma of brains from fetus and newborns (22-40 weeks of gestation), suffering from dilatation of the ventricular system has been studied by immunohistochemical method. The increasing of S-100 expression in germinal matrix and subcortex under hydrocephaly was significantly higher than in cases of ventriculomegalia (p < 0.01) and control group (p < 0.05). The index of S-100 expression could be use as prognostic criteria of neuron and neuroglia mortality for differential diagnosis of hydrocephaly.

Clinical and histopathological profile of primary or secondary osteosarcoma of the jaws

Osteosarcoma of the jaw is a rare disease; we report two cases, one in which the primary osteosarcoma had occurred in the sacrum and ileum, the second at the mandible. Dissemination of osteosarcoma to other organs, especially early dissemination to the lung, is common, but metastasis to the jaw has only rarely been reported. About 10% of osteosarcomas occur in the head and neck, most in the mandible or maxilla. Clinically, both patients presented swelling, and pain at the jaw in the premolar-molar region. At radiography, extensive bone erosion and soft-tissue swelling were apparent. A biopsy was taken and a diagnosis of osteosarcoma rendered in both cases. Histological examination revealed a proliferation of atypical osteoblast-like cells with hyperchromatic nuclei and formation of scattered neoplastic osteoid tissue. Immunohistochemistry for a panel of antibodies showed strong positivity for CD99, weak positivity for S-100, but was negative for desmin, vimentin, and cytokeratins. The diagnosis for both cases was of osteogenic osteosarcoma, chondroblastic subtype. Unfortunately, both patients died, one before the planned chemotherapy regime could begin, the second during the chemotherapy course. Our report aims to highlight the importance of the diagnostic profile in formulating a diagnosis of osteosarcoma, and that this tumor, although very rare, may be primary or may metastasize to the jaws.

S100A2 level changes are related to human periodontitis

Periodontitis is an inflammatory disease, which, when severe, can result in tooth loss, that affects the quality of life. S100A2 was previously identified as a component of gingival crevicular fluid (GCF) via proteome analysis, but it has not been investigated whether S100A2 plays a role in periodontitis. In this study, we analyzed mRNA expression of S100A2 in gingival tissues from normal and classified periodontal disease patients and compared it to that of S100A8 and S100A9. Quantitative real time-PCR revealed that the mRNA expression levels of S100A2, S100A8, and S100A9 were significantly upregulated in gingival tissues with gingivitis, moderate periodontitis, and severe periodontitis compared to normal tissues. In addition, S100A2 proteins in GCF and the conditioned media of lipopolysaccharide (LPS)-treated Jurkat cells were confirmed by ELISA. S100A2 protein levels were significantly higher in GCF in gingivitis and moderate periodontitis groups than in normal groups. S100A2 mRNA expression and protein secretion were also increased by LPS stimulation. Based on the up-regulation of S100A2 in LPS-stimulated immune cells, gingival tissues and GCF from periodontal disease groups, we conclude that S100A2 is a functional component in the immune response during periodontitis and may serve as a potential biomarker for periodontitis.

Primary myoepithelial carcinoma of palate

OBJECTIVES

The aim of this study was to present a rare neoplasm, Primary myoepithelial carcinoma arising from the palate, and to review its diagnostic criteria, pathologic and clinical characteristics, treatment options and prognosis.

CLINICAL PRESENTATION AND INTERVENTION

Myoepitheliomas are tumors arising from myoepithelial cells mainly or exclusively. Myoepitheliomas mostly occur in salivary glands, as well as in breast, skin, and lung. Case of myoepitheliomas in palate has rarely been reported. Myoepithelial carcinoma is malignant counterpart of myoepitheliomas. Adenomyoepithelioma is also a different disease from myoepitheliaomas. Immunohistochemically, tumor cells of myoepithelial carcinoma express not only epithelial markers such as cytokeratin, epithelial membrane antigen (EMA), but also markers of smooth muscle origin such as calponin. The immunohistochemical criteria of myoepithelial differentiation are double positive for both cytokeratins and one or more myoepithelial immunomarkers (i.e., S-100 protein, calponin, p63, GFAP, maspin, and actins). Myoepithelial carcinomas of salivary and breast demonstrate copy number gains and gene deletion. The overall prognosis of myoepithelial carcinoma is poor. There is rarely recurrence or metastasis in benign myoepithelial tumors. Complete excision with tumor-free margin is always the preferred treatment, while local radiation therapy and chemotherapy are suggestive treatment options. Here, a rare case of myoepithelial carcinoma arising from the palate has been described and discussed for the treatment and outcome. Pathological and clinical characters of myoepitheliomas are also compared and discussed.

CONCLUSION

The case report serves to increase awareness and improve the index of diagnosis and treatment of myoepitheliomas.

High expression of S100A11 in pancreatic adenocarcinoma is an unfavorable prognostic marker

S100A11 is a member of S100 protein family, and our previous study showed that S100A11 is one of the up-regulated proteins that have not been reported to be associated with pancreatic carcinoma. The purpose of this study was to investigate the relation between S100A11 expression and the clinicopathological variables and clinical outcome in patients with pancreatic adenocarcinoma. Immunohistochemistry analysis was performed for S100A11 in 78 pairs of specimens of human pancreatic adenocarcinoma tissues and adjacent nontumorous tissues. The univariate and multivariate survival analyses were also performed to determine its prognostic significance. S100A11 expression in pancreatic adenocarcinoma (62/78) was significantly higher than that in the adjacent nontumorous tissues (19/78) (P = 0.000). High expression of S100A11 was associated with the lymph node metastasis and histological differentiation (P = 0.003 and 0.004, respectively). Univariate analysis showed that S100A11 expression was associated with poor prognosis (P = 0.0000). Multivariate analysis using the Cox regression model indicated that age ≥ 65 years, CA19-9 ≥ 1,000 U/ml and positive S100A11 were independent prognostic indicators of pancreatic adenocarcinoma (P = 0.002, 0.004 and 0.001, respectively). These results suggested that S100A11 might be a significant tumor marker for pancreatic adenocarcinoma and an unfavorable predictor for prognosis of patients who have undergone surgical resection.

S100A1 genetically targeted therapy reverses dysfunction of human failing cardiomyocytes

OBJECTIVES

This study investigated the hypothesis whether S100A1 gene therapy can improve pathological key features in human failing ventricular cardiomyocytes (HFCMs).

BACKGROUND

Depletion of the Ca²⁺-sensor protein S100A1 drives deterioration of cardiac performance toward heart failure (HF) in experimental animal models. Targeted repair of this molecular defect by cardiac-specific S100A1 gene therapy rescued cardiac performance, raising the immanent question of its effects in human failing myocardium.

METHODS

Enzymatically isolated HFCMs from hearts with severe systolic HF were subjected to S100A1 and control adenoviral gene transfer and contractile performance, calcium handling, signaling, and energy homeostasis were analyzed by video-edge-detection, FURA2-based epifluorescent microscopy, phosphorylation site-specific antibodies, and mitochondrial assays, respectively.

RESULTS

Genetically targeted therapy employing the human S100A1 cDNA normalized decreased S100A1 protein levels in HFCMs, reversed both contractile dysfunction and negative force-frequency relationship, and improved contractile reserve under beta-adrenergic receptor (β-AR) stimulation independent of cAMP-dependent (PKA) and calmodulin-dependent (CaMKII) kinase activity. S100A1 reversed underlying Ca²⁺ handling abnormalities basally and under β-AR stimulation shown by improved SR Ca²⁺ handling, intracellular Ca²⁺ transients, diastolic Ca²⁺ overload, and diminished susceptibility to arrhythmogenic SR Ca²⁺ leak, respectively. Moreover, S100A1 ameliorated compromised mitochondrial function and restored the phosphocreatine/adenosine-triphosphate ratio.

CONCLUSIONS

Our results demonstrate for the first time the therapeutic efficacy of genetically reconstituted S100A1 protein levels in HFCMs by reversing pathophysiological features that characterize human failing myocardium. Our findings close a gap in our understanding of S100A1's effects in human cardiomyocytes and strengthen the rationale for future molecular-guided therapy of human HF.

Identification of tumoral glial precursor cells in neuroblastoma

Neuroblastic tumors (NBT) are composed by neuroblasts and Schwannian-like stroma. The origin of these two cell subtypes remains unclear. In this study, we describe, a neuroblastic-like subpopulation in neuroblastoma (NB) coexpressing GD2 and S100A6, neuroblastic and glial lineage markers respectively. The GD2(+)/S100A6(+) neuroblastic subpopulation was found to be enriched in low risk NB, distributed around the perivascular niche. Some stromal bundles showed GD2(+)/S100A6 costaining. Metastatic bone marrow specimens also showed GD2(+)/S100A6(+) cells. During in vitro retinoic acid induced differentiation of NB cell lines, rare GD2(+)/S100A6 neuroblatic cells appeared. We conclude that GD2(+)/S100A6(+) neuroblasts may represent a tumoral glial precursor subpopulation in NBT.

[Identification of proteins overexpressed in malignant gastric tumors: comparison of the results of 2-De and bioinformatics search]

Comparison of protein expression in intestinal and diffuse stomach tumors by 2D gel electrophoresis led to identification of three proteins (SOD2, S100A6, and TXN), which are overexpressed in tumors as compared to normal controls. It was shown, that overexpression of proteins SOD2 and TXN occurs much more frequently in diffuse tumors than in intestinal ones. A control panel of eleven proteins overexpressed in stomach tumors has been selected based on the data of comparative 2D analysis described in the literature. Bioinformatics search for mRNAs encoding proteins from the control panel in Oncomine database (which contains the results of determination of mRNA transcription level in tumor vs. normal samples) demonstrated the coincidence of proteomic and transcriptomic data for seven out of 11 proteins.

Onset and dynamic expression of S100 proteins in the olfactory organ and the lateral line system in zebrafish development

In the zebrafish olfactory epithelium, three morphologically distinct olfactory neurons express different marker proteins. We utilize this feature to access developmental dynamics of one of the neuron types, the crypt cells, to determine whether they are differentiated at a stage similar to other olfactory neurons. Immunohistochemical studies using an S100 antibody that specifically recognizes crypt cells showed that S100-positive cells appear in olfactory rosettes as early as at 2day postfertilization (dpf). However, some of the rosettes did not have any S100-positive cells until 4 dpf. The number of S100-positive cells in individual rosettes increased steadily over the next 3days before it decreased significantly. There were 7.8 S100-positive cells per rosettes on average in larvae at 7 dpf. The number reduced to 2.2 at 9 dpf. A recovery to a pre-reduction level was detected in 12 dpf larvae. We also observed S100-positive cells in neuromasts of the lateral line system in 2 dpf larvae, suggesting that the crypt cells and sensory cells in the neuromasts have similar onsets of differentiation. Our data have provided a time line of differentiation of crypt cells in development of the olfactory system and demonstrated that this type of cell is differentiated at a stage similar to ciliated and microvillous olfactory neurons. A nonlinear growth trajectory of the crypt cell population in the first nine days of zebrafish development implicates a possible functional significance of crypt cells in early life stages of zebrafish.

RAGE ligands induce apoptotic cell death of pancreatic β-cells via oxidative stress

Activation of the receptor for advanced glycation endproducts (RAGE) by its ligands leads to cellular damage contributing to diabetic complications. It is not clearly known whether RAGE ligands influence pancreatic β-cells. In this study, we investigated the expression of RAGE in islet cells and the effect of RAGE ligands, S100b and HMG-1, on islet cells. RAGE was expressed in INS-1 cells and isolated rat and human islets at mRNA and protein levels. RAGE and its ligand, S100b, were detected on islet cells in 28-week-old diabetic OLETF rats. Both S100b and HMG-1 induced apoptotic cell death of INS-1 and islet cells. This INS-1 cell apoptosis was accompanied by increased intracellular oxidative stress and inhibited by antioxidants or a NADPH oxidase inhibitor. Our results showing S100b/RAGE expression on islets of diabetic rat model and RAGE ligands-induced islet cell apoptosis via NADPH oxidase-mediated ROS generation suggest that RAGE ligands-RAGE interaction may contribute not only to the development of diabetic complications but also to the progressive β-cell loss in type 2 diabetes by inducing oxidative stress.

Proteomic study of thyroid tumors reveals frequent up-regulation of the Ca2+ -binding protein S100A6 in papillary thyroid carcinoma

BACKGROUND

The accurate diagnosis of thyroid tumors is challenging. Proteomics has emerged as a promising approach for the discovery of molecular diagnostic markers as a potential complement to routine diagnostics.

METHODS

Protein fractions from 29 frozen thyroid tumor tissue samples (10 papillary carcinomas, 9 follicular carcinomas, and 10 follicular adenomas) as well as from normal thyroid tissue were analyzed by surface enhanced laser desorption/ionization time-of-flight mass spectrometry followed by validation by Western blotting and immunohistochemistry.

RESULTS

A Ca2+ binding protein belonging to the S100 family, S100A6, was differentially expressed between papillary and follicular thyroid tumors. Moreover, two posttranslationally modified forms of S100A6 were observed and verified by liquid chromatography-coupled tandem mass spectrometry. Validation by Western blotting displayed a significantly higher expression of S100A6 in papillary thyroid carcinoma (PTC) in comparison with the other tumor groups or normal tissue (p < 0.05). Immunohistochemical analysis on 98 tumors showed that PTC cases had a significantly stronger cytosolic staining and a larger proportion of stained nuclei than follicular tumors. BRAF gene mutation was not significantly associated with S100A6 protein levels.

CONCLUSION

This study supports a role of S100A6 in thyroid tumorigenesis and as a potential aid in the discrimination between follicular thyroid tumors and PTC.

Hypomethylation-induced expression of S100A4 increases the invasiveness of laryngeal squamous cell carcinoma

The present study aimed to identify genes related to 5AZA-CdR in laryngeal squamous cell carcinoma (LSCC) and to investigate the role of S100A4 in the development and aggression of LSCC. Differentially expressed proteins were identified in Hep-2 cells treated with 5AZA-CdR by two-dimensional gel electrophoresis combined with MALDI-TOF-MS. mRNA, protein levels and DNA methylation status of S100A4 were assessed by RT-PCR, Western blotting and methylation-specific PCR, respectively. The invasiveness of Hep-2 cells transfected by siRNA S100A4 was determined by transwell migration assay. Protein profiles from Hep-2 cells treated with 5AZA-CdR were obtained, and several differentially expressed proteins such as S100 calcium-binding protein A4 (S100A4) were identified. Results of RT-PCR and Western blotting revealed that both mRNA and protein levels of S100A4 were significantly higher in the metastatic lymph nodes than those in paired adjacent normal laryngeal (PANL) or tumor tissues. The DNA methylation status displayed significant differences between the LSCC and the PANL tissues. The expression level of S100A4 decreased in Hep-2 cells undergoing RNA interference of S100A4. The number of cells which crossed the basement membrane filter was significantly lower in the RNAi S100A4 group when compared with the number in the control group. The abnormal expression of S100A4 identified in Hep-2 cells treated with an inhibitor of DNA methyltransferase appeared to result from the aberrant DNA methylation status of S100A4. The abnormal expression of S100A4 altered the invasiveness of LSCC.

Evidence for diminished levels of epithelial psoriasin and calprotectin in chronic rhinosinusitis

BACKGROUND

Decreased epithelial expression of mRNA for S100A7 (psoriasin) and S100A8/A9 (calprotectin) has been reported in patients with chronic rhinosinusitis (CRS).

OBJECTIVES

We sought to assess whether the expression of S100 proteins is also altered in the sinonasal cavity of patients with CRS.

METHODS

We determined levels of S100 proteins in nasal lavage fluid and sinonasal tissue extracts from patients with CRS using ELISA and immunohistochemical analysis of nasal polyp tissue from patients with CRS with nasal polyps and uncinate tissue from healthy control subjects, patients with CRSsNP, and patients with CRSwNP.

RESULTS

Expression levels of S100 proteins were decreased compared with those seen in control subjects in nasal lavage fluid from both CRS groups (P < .05). Similarly, tissue expression of these proteins assessed by means of immunohistochemistry demonstrated clear reductions, primarily in the epithelial lining. Interestingly, levels of calprotectin were increased in nasal polyp tissue despite lower levels in lavage fluid. Levels of calprotectin in nasal tissues were correlated with levels of neutrophils, as assessed by means of quantification of neutrophil elastase.

CONCLUSIONS

Several S100 proteins are in the epidermal differentiation complex of genes and have been demonstrated to play a role in maintenance of barrier function and formation of an antimicrobial shield. We demonstrate significantly decreased levels of expression of S100 proteins in the epithelium of patients with CRS, which might lead to diminished innate immune responses and barrier function. Increased levels of calprotectin in nasal polyp tissue might reflect neutrophil recruitment and a compensatory mechanism. Future studies will be important to determine whether reduced levels of S100 proteins lead to decreased antimicrobial responses in the upper airways and sinuses and whether this reduction plays a causative role in CRS pathogenesis and susceptibility to infectious disease.

Expression status of S100A14 and S100A4 correlates with metastatic potential and clinical outcome in colorectal cancer after surgery

To investigate whether S100A14 and S100A4 expression correlates with metastatic potential and prognosis in colorectal cancer (CRC), we firstly used RT-PCR analysis to detect mRNA expression of S100A14 and S100A4 in 40 pairs of fresh tumor samples matched with adjacent normal tissues. We then evaluated the clinical significance of our findings with immunohistochemistry on 115 samples of formalin-fixed and paraffin-embedded tumors on tissue microarrays. Typically, we identified decreased S100A14 mRNA levels (52.5%, 21/40), and increased S100A4 mRNA levels (70.0%, 28/40) in primary CRC samples. In addition, down-regulated or absent S100A14 expression was detected in 56.5% of samples (65/115) and was correlated with poor differentiation (P=0.010). In contrast, overexpressed S100A4 was detected in 57.4% of samples (66/115) and was associated with lymph node metastasis (P=0.001). Simultaneous S100A14 low-expression and S100A4 high-expression was correlated with high CRC metastatic potential (P<0.001). Taken together, the signature derived from the combined expression status of S100A14 and S100A4 could be a valuable prognostic indicator in CRC.

The Biocompatibility Research of Functional Schwann Cells Induced from Bone Mesenchymal Cells with Chitosan Conduit Membrane

To explore the adhesion and proliferation characteristics of bone marrow mesenchymal cells (MSCs) to chitosan conduit membrane, MSCs were induced by a sequential composition Beta-mercaptoethanol, retinoic acid, forskolin, basic-FGF, PDGF and heregulin. Schwann Cell markers, namely S-100 and GFAP, were used to discriminate the induced MSCs' properties by immunofluorescent staining. These results suggested that MSCs can take on Schwann cell's phenotype in vitro and the induce MSCs were gifted with good biocompatibility to biogradable chitosan conduit membrane. The results provided the possibilities to using the induced MSCs with chitosan conduit membrane in artificial peripherial nerve fields to promote nerve regeneration.

Expression of S100A6 in cardiac myocytes limits apoptosis induced by tumor necrosis factor-alpha

S100A6 is induced in myocardium post-infarction in vivo and in response to growth factors and inflammatory cytokines in vitro. Forced expression of S100A6 in cardiomyocytes inhibits regulation of cardiac specific gene expression in response to trophic stimulation. To define regulation and function of S100A6, we characterized the human S100A6 promoter and mapped upstream regulatory elements in rat neonatal cardiac myocytes, fibroblasts, and vascular smooth muscle cells and defined a functional role for S100A6 in tumor necrosis factor-alpha-induced myocyte apoptosis. The functional S100A6 promoter was localized to region -167/+134 containing 167 upstream base pairs. The S100A6 promoter is regulated by positive (-361/-167 and -588/-361) and negative (-1371/-1194) elements. Tumor necrosis factor-alpha induced the maximal S100A6 promoter and transcription factor NF-kappaB (p65 subunit). Electrophoretic mobility shift showed that tumor necrosis factor-alpha induced p65 binding to a potential NF-kappaB-binding site at -460/-451. Chromatin immunoprecipitation analysis revealed p65 is recruited to the S100A6 promoter upon tumor necrosis factor-alpha stimulation. The NF-kappaB inhibitor caffeic acid phenethyl ester and mutation of the NF-kappaB-binding site inhibited S100A6 promoter activation by tumor necrosis factor-alpha. Tumor necrosis factor-alpha induced cardiac myocyte apoptosis. Specific inhibition of S100A6 using a small interfering RNA directed against S100A6 potentiated tumor necrosis factor-alpha-induced myocyte apoptosis, whereas overexpression of S100A6 by gene transfer prevented tumor necrosis factor-alpha-induced myocyte apoptosis by interfering with p53 phosphorylation. These results demonstrate that S100A6 is induced by tumor necrosis factor-alpha via an NF-kappaB-dependent mechanism, serving a role in homeostasis to limit tumor necrosis factor-alpha-induced apoptosis by regulating p53 phosphorylation.

Vanadium (V)-Induced Neurotoxicity in the Rat Central Nervous System: A Histo-Immunohistochemical Study

As vanadium was found to induce oxidative stress in the central nervous system, the morphological alterations of neurons and astroglial cells in adult rat central nervous system after vanadium exposure was studied, using histological markers of cellular injury. Animals were intraperitoneally injected with 3 mg/kg body weight of sodium metavanadate for 5 consecutive days. NADPH diaphorase histochemistry and heat shock protein (hsp) 70, glial fibrillary acidic protein (GFAP), and S-100 immunohistochemistry were performed in floating sections of several brain areas. NADPHd staining was higher in the molecular and granular layers of the cerebellar cortex, and small NADPHd-stained interneurons were observed in hippocampal sections in V(+5)-exposed animals. hsp 70 immunostaining showed the presence of reactive neurons in cerebellum of treated animals. GFAP and S-100 immunohistochemistry showed enlarged astrocytes in cerebellum and hippocampus in the V(+5)-exposed animals. The histological markers used showed that the main areas affected by vanadium-mediated free-radical generation were the hippocampus and the cerebellum.

Glial fibrillary acidic protein and S-100 colocalization in the enteroglial cells in dilated and nondilated portions of colon from chagasic patients

After acute immunoreactive infestation with the Chagas' disease parasite, Trypanosoma cruzi, some patients develop chronic megacolon, whereas others remain asymptomatic. Chronic chagasic patients with gastrointestinal involvement exhibit inflammation and degeneration of enteric neurons. Our hypothesis is that enteric glial cells may be involved in the modulation of enteric inflammatory responses or even control the colon's dilatation. The aims of this study were to characterize the phenotype of enteric glial cells according to the expression of S-100 and glial fibrillary acidic protein and to look for correlation between these data and the neuronal loss in the colon of chagasic patients. We studied both dilated and nondilated portions of chagasic megacolon. We used a pan-enteric glial cell marker (anti-S-100), a subpopulation enteric glial cell marker (anti-glial fibrillary acidic protein), and a pan-neuronal marker (anti-Human protein C and protein D) with double-labeled sheets using a confocal microscope. Our results demonstrate that neuronal loss is similar in dilated and nondilated portions of chagasic megacolon. Moreover, the results indicate that neuronal destruction present in chagasic megacolon is preceded by glial component loss. The nondilated portion of chagasic megacolon exhibited increased expression of glial fibrillary acidic protein comparable with the dilated portion and also to the noninfected group. Our results suggest that glial fibrillary acidic protein enteric glial cells prevent dilatation of the organ and protect the enteric nervous system against the inflammatory process and neuronal destruction, preventing the destruction from expanding to unaffected areas of the colon.

[Overexpressing exogenous S100A13 gene and its effect on proliferation of human thyroid cancer cell line TT]

BACKGROUND & OBJECTIVE

S100A13 is involved in tumor formation, and is highly expressed in human thyroid gland. This study was to investigate the effect of exogenous S100A13 overexpression on the proliferation of human thyroid cancer cell line TT.

METHODS

The eukaryotic expression plasmid pCDNA3.1/NT-GFP-S100A13 and empty vector pCDNA3.1/NT-GFP were transfected into TT cells. The cells were selected by G418. The expression of green fluorescent protein (GFP) was observed under laser scanning microscope, and the expression of S100A13 mRNA and protein was detected by real-time reverse transcription-polymerase chain reaction (RT-PCR) and Western blot. The effects of S100A13 on cell proliferation and cell cycle progression were measured by cell growth curve and flow cytometry.

RESULTS

TT-S100A13-GFP and TT-GFP cells, which separately expressed S100A13 and pCDNA3.1/NT-GFP, were constructed successfully. TT-S100A13-GFP cells grew faster than TT-GFP and TT cells [(2.30+/-0.24) x 10(5) vs. (1.40+/-0.25) x 10(5) and (1.50+/-0.22) x 10(5) at the 7th day of cell culture, P<0.05]; both S phase proportion and G2/M phase proportion were significantly higher in TT-S100A13-GFP cells than in TT-GFP and TT cells [(6.47+/-0.14)% vs. (5.86+/-0.23)% and (5.99+/-0.28)% at S phase, P<0.05; (50.27+/-0.66)% vs. (39.39+/-0.23)% and (39.64+/-0.64)% at G2/M phase, P<0.05].

CONCLUSION

Exogenous S100A13 gene overexpression could accelerate cell proliferation, and promote cell cycle progression of TT cells from G0/G1 phase to S and G2/M phase.