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Purpose: Neutrophil gelatinase-associated lipocalin receptor (NGALR) mRNA level is reduced in isolated chronic myelogenous leukemia blasts but up-regulated in esophageal squamous cell carcinoma (ESCC). The mechanism of NGALR regulation is unknown. Here, we show the expression pattern of NGALR and examine the aberrant methylation of its gene in ESCC and esophageal carcinoma cell lines.Experimental Design: The expression pattern of NGALR was analyzed by immunohistochemistry in 59 ESCCs and compared with noncancerous tissues. The DNA methylation status was investigated by methylation-specific PCR and by bisulfite genomic sequencing in esophageal carcinoma cell lines and surgically resected samples. Methylated cell lines were treated with a methylation inhibitor to restore NGALR expression.Results: The expression of NGALR in ESCC was significantly higher in tumor cell membrane and cytoplasm than in normal esophageal epithelium (P < 0.01). Methylated alleles were detected in three NGALR-nonexpressing cell lines but were not detected in three NGALR-expressing cell lines. Treatment of methylated cell lines with 5-aza-2′-deoxycytidine, a methylation inhibitor, restored NGALR expression. In surgically resected samples, 31 of 77 (40.3%) primary esophageal carcinomas and 46 of 77 (59.7%) paired normal tissues contained methylated NGALR alleles (P < 0.05).Conclusions: Our results suggest that NGALR hypomethylation contributes to its expression in esophageal carcinomas and that this overexpression may play a role in the pathogenesis of esophageal carcinomas.

Supplementary Data from NGALR Is Overexpressed and Regulated by Hypomethylation in Esophageal Squamous Cell Carcinoma

This paper proposes a new frequency-domain pre-coding algorithm for the downlink multi-user MIMO system in a frequency-selective fading channel, where each user is equipped with multiple antennas. The proposed algorithm is based on the minimum sum-mean-square-error (Min-SMSE) criterion, which is able to eliminate both the multi-user and multi-antenna interferences, resulting in an improved bit error rate (BER) performance. Compared with the traditional optimal Min-SMSE algorithm, the proposed algorithm can reduce the computational complexity through simplifying the iterative and power allocation processes. Furthermore, the theoretical BER and ergodic sum-rate are derived in detail. In addition, we define and analyze the complexity of the pre-coding algorithms. Simulation results show that the proposed algorithm compares favorably with the optimal Min-SMSE and traditional block diagonalization (BD) algorithms in the sense of the ergodic sum-rate due to the approximately equal power allocation. The BER performance of the proposed algorithm is close to that of the optimal one and much better than that of the BD algorithm in both the uncorrelated and correlated channels. Moreover, the computational complexity of the sub-optimal Min-SMSE algorithm is significantly less than that of its optimal counterpart, especially in the low SNR region.

Background Photodynamic therapy (PDT) is a promising anti-tumor treatment strategy. Photosensitizer is one of the most important components of PDT. In this work, the anticancer activities of PDT mediated by six new ruthenium porphyrin complexes were screened. The mechanisms of the most efficacious candidate were investigated. Methods Photocytotoxicity of the six porphyrins was tested. The most promising complex, Rup-03, was further investigated using Geimsa staining, which indirectly detects reactive oxygen species (ROS) and subcellular localization. Mitochondrial membrane potential (MMP), cell apoptosis, DNA fragmentation, c-Myc gene expression, and telomerase activities were also assayed. Results Rup-03 and Rup-04 had the lowest IC 50 values. Rup-03 had an IC 50 value of 29.5 ± 2.3 μM in HepG2 cells and 59.0 ± 6.1 μM in RAW264.7 cells, while Rup-04 had an IC 50 value of 40.0 ± 3.8 μM in SGC-7901 cells. The complexes also induced cellular morphological changes and impaired cellular ability to scavenge ROS, and accumulated preferentially in mitochondria and endoplasmic reticulum. Rup-03 reduced MMP levels, induced apoptosis, and repressed both c-Myc mRNA expression and telomerase activity in HepG2 cells. Conclusions Among six candidates, Rup-03-mediated PDT is most effective against HepG2 and RAW264.7, with a similar efficacy as that of Rup-04-mediated PDT against SGC-7901 cells. Repression of ROS scavenging activities and c-Myc expression, which mediated DNA damage-induced cell apoptosis and repression of telomerase activity, respectively, were found to be involved in the anticancer mechanisms of Rup-03.

Context: The effects of icariin, a chief constituent of flavonoids from Epimedium brevicornum Maxim (Berberidaceae), on the levels of HIF-1α, HSP-60 and HSP-70 remain unknown. Objective: To explore the effects of icariin on the levels of HSP-60, HIF-1α and HSP-70 neuron-specific enolase (NSE) and cell viability. Materials and methods: PC12 cells were treated with icariin (10−7, 10−6 or 10−5 mol/L) for 3 h (1 h before oxygen–glucose deprivation (OGD) plus 2 h OGD). HSP-60, HIF-1α, HSP-70 and NSE were measured using enzyme-linked immunosorbent assay (ELISA). Cell viability was determined by metabolic 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Results: After 2 h OGD, levels of HIF-1α, HSP-60, HSP-70 and NSE were increased significantly (HIF-1α: 33.3 ± 1.9 ng/L, HSP-60: 199 ± 16 ng/L, HSP-70: 195 ± 17 ng/L, NSE: 1487 ± 125 ng/L), and cell viability was significantly decreased (0.26 ± 0.03), while icariin (10−7, 10−6, or 10−5 mol/L) significantly reduced the contents of HIF-1α, HSP-60, HSP-70 and NSE (HIF-1α: 14.1 ± 1.4, 22.6 ± 1.8, 15.7 ± 2.1, HSP-60: 100 ± 12, 89 ± 6, 113 ± 11, HSP-70: 139 ± 9, 118 ± 7, 95 ± 9 and NSE: 1121 ± 80, 1019 ± 52, 731 ± 88), and improved cell viability (0.36 ± 0.03, 0.38 ± 0.04, 0.37 ± 0.03) in OGD-treated PC12 cells. Discussion and conclusion: These results indicate that the protective mechanisms of icariin against OGD-induced injury may be related to down-regulating the expression of HIF-1α, HSP-60 and HSP-70.

Dibromoacetic acid (DBA) is one of haloacetic acids, often as a by-product of disinfection in drinking water. DBA is a multiple-organ carcinogen in rodent animals, but little research on its hepatotoxicity has been conducted and its mechanism has not been elucidated. In this study, we found that DBA could induce obvious hepatotoxcity in Balb/c mice as indicated by histological changes, increasing serum level of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), and accumulation of hepatic glycogen, after the mice were administered DBA at doses of 1.25, 5, and 20 mg/kg body weight for 28 days via oral gavage. In mechanism study, DBA induced oxidative stress as evidenced by increasing the level of malondialdehyde (MDA), reactive oxygen species (ROS) in the liver, advanced oxidative protein products (AOPPs) in the serum, and decreasing the level of glutathione (GSH) in the liver. DBA induced inflammation in the liver of the mice which is supported by increasing the production of tumor necrosis factor-α (TNF-α) and the mRNA levels of TNF-α, interleukin-6 (IL-6), interleukin-1β (IL-1β), and nuclear factor κB (NF-κB) in the liver. DBA also upregulated the protein levels of Toll-like receptor (TLR) 4, myeloid differentiation factor 88 (MyD88), tumor necrosis factor receptor-associated factor 6 (TRAF6), inhibitor of nuclear factor κB alpha (IκB-α), nuclear factor κB p65 (NF-κB p65), and the phosphoralation of P38 mitogen-activated protein kinase (P38MAPK) and c-Jun N-terminal kinase (JNK). Conclusion. DBA could induce hepatotoxicity in mice by oral exposure; the mechanism is related to oxidative stress, inflammation, and Toll-like receptor 4 signaling pathway activation.

Dibromoacetic acid (DBAA), a haloacetic acid found in drinking water as a disinfection by-product, can cause many adverse effects, including immunotoxicity. In a previous study, we confirmed that DBAA can induce obvious immunotoxicity in mice but that the underlying mechanisms are not clearly understood. In our current study, we confirmed that DBAA induced cytotoxicity and apoptosis in thymocytes isolated from mice by a range of DBAA concentrations (0, 5, 10, 20, or 40 μM). The data showed that DBAA exposure led to a significant decrease in proliferative responses to T-cell mitogens and obvious inhibition in the production of cytokines interleukin-2 and interleukin-4. We found obvious morphological changes of apoptosis in thymocytes and observed the percentage of apoptotic thymocytes to increase significantly as the DBAA concentration increased. Further investigation showed that DBAA can cause G0/G1 arrest in cell cycle analysis, increase intracellular calcium ([Ca2+]i) levels, increase the expression of Fas/FasL proteins, and decrease the expression of Bcl-2 protein. It is concluded that in vitro exposure to DBAA can lead to marked cytotoxicity and apoptosis among thymocytes, and the mechanism involved is strongly related to blocking cell cycle progression, increasing intracellular calcium, and increasing Fas/FasL expressions.

Dibromoacetic acid (DBA), a haloacetic acid by-product of disinfection of drinking water, can cause many adverse effects in test animals, including immunotoxicity. However, the underlying molecular mechanism for the immunomodulatory effects remains unclear. The present study was undertaken to help in defining some potential mechanisms for this type of toxicity. Here, Cl.Ly1+2/-9 T-cells were exposed to varying levels of DBA and then several parameters, including cell survival, apoptosis, changes in mitochondrial potentials, and effects on select kinases (i.e., p38, ERK1/2, JNK1/2) were examined. The data showed that DBA significantly decreased Cl.Ly1+2/-9 cell viability in a dose-related manner. DBA also induced apoptosis, a decrease in mitochondrial trans-membrane potential, and up-regulated the protein expression of cleaved caspase-3. Moreover, DBA increased the phosphorylation of all three mitogen-activated protein kinases (MAPKs) evaluated. Pre-treatment with specific p38, ERK1/2, and JNK1/2 inhibitors (SB203580, U0126, SP600125, respectively) attenuated the inducible phosphorylation events. DBA also induced up-regulation of mRNA levels of the MAPKs downstream transcription factors ATF-2 and Elk-1. When taken together, the results suggest that DBA could induce murine Cl.Ly1+2/-9 T-cells apoptosis through mitochondria-dependent way, and activate the MAPKs pathways and downstream transcription factors ATF-2 and Elk-1.

This paper offers a DMO (direct mode operation) design applied to TD-LTE. It can support point to point full-duplex communication in the no signal covered area and user switching according to their priority at the same time. The design divides channel into access channel and communication channel to improve the spectrum efficiency. When the SNR is higher than 16dB, the DMO design using QPSK modulation has a BER (bit error rate) reaching 10-4 under ITU-R M1225 channel B. Although at the same BER value, the SNR requirements of IFDMA has a 0.5dB lower than LFDMA, given that TD-LTE uses LFDMA and LFDMA has a good resistance to frequency offset and is much easier to realize, we adopt LFDMA as subcarrier mapping method in the DMO design. Besides, at the same BER value, the required SNR of MMSE (minimum mean square error) equalization is 1.0~1.5dB lower than the required SNR of the ZF (zero-forcing) equalization. Therefore DMO should use MMSE equalization in the low SNR environment and ZF equalization in the high SNR environment.

he creation of generalized structure module model is studied in this paper. Firstly, the component of generalized structure module is analyzed by the form of sets, then the modeling process of generalized structure module is explained, also the method of similar feature clustering-based for modeling is presented. Finally, an example of the drafting module in flyer frame is given.

The overexpression of fascin in human carcinomas is associated with aggressive clinical phenotypes and poor prognosis. However, the molecular mechanism underlying the increased expression of fascin in cancer cells is largely unknown. Here, we identified a Sp1 binding element located at -70 to -60 nts of the FSCN1 promoter and validated that Sp1 specifically bound to this element in esophageal carcinoma cells. Fascin expression was enhanced by Sp1 overexpression and blocked by Sp1 RNAi knockdown. Specific inhibition of ERK1/2 decreased phosphorylation levels of Sp1, and thus suppressed the transcription of the FSCN1, resulting in the down-regulation of fascin. Stimulation with EGF could enhance fascin expression via activating the ERK1/2 pathway and increasing phosphorylation levels of Sp1. These data suggest that FSCN1 transcription may be subjected to the regulation of the EGF/EGFR signaling pathway and can be used as a viable biomarker to predict the efficacy of EGFR inhibitors in cancer therapies.

Ezrin, encoded by VIL2, is a membrane-cytoskeletal linker protein that has been suggested to be involved in tumorigenesis. Ezrin expression in esophageal squamous cell carcinoma (ESCC) was described recently, but its clinical significance and the molecular mechanism underlying its regulated expression remain unclear. Thus, we retrospectively evaluated ezrin expression by immunohistochemistry in a tissue microarray representing 193 ESCCs. Ezrin overexpression in 90 of 193 tumors (46.6%) was associated with poor survival (p = 0.048). We then explored the mechanism by which ezrin expression is controlled in ESCC by assessing the transcriptional regulatory regions of human VIL2 by fusing deletions or site-directed mutants of the 5′-flanking region of the gene to a luciferase reporter. We found that the region -87/-32 containing consensus Sp1 (-75/-69) and AP-1 (-64/-58) binding sites is crucial for VIL2 promoter activity in esophageal carcinoma cells (EC109) derived from ESCC. AP-1 is comprised of c-Jun and c-Fos. Electrophoretic mobility shift and chromatin immunoprecipitation experiments demonstrated that Sp1 and c-Jun bound specifically to their respective binding sites within the VIL2 promoter. In addition, transient expression of Sp1, c-Jun, or c-Fos increased ezrin expression and VIL2 promoter activity. Use of selective inhibitors revealed that VIL2 transactivation required the MEK1/2 signal transduction pathway but not JNK or p38 MAPK. Taken together, we propose a possible signal transduction pathway whereby MEK1/2 phosphorylates ERK1/2, which phosphorylates Sp1 and AP-1 that in turn bind to their respective binding sites to regulate the expression of human VIL2 in ESCC cells.

Purpose: Neutrophil gelatinase-associated lipocalin receptor (NGALR) mRNA level is reduced in isolated chronic myelogenous leukemia blasts but up-regulated in esophageal squamous cell carcinoma (ESCC). The mechanism of NGALR regulation is unknown. Here, we show the expression pattern of NGALR and examine the aberrant methylation of its gene in ESCC and esophageal carcinoma cell lines. Experimental Design: The expression pattern of NGALR was analyzed by immunohistochemistry in 59 ESCCs and compared with noncancerous tissues. The DNA methylation status was investigated by methylation-specific PCR and by bisulfite genomic sequencing in esophageal carcinoma cell lines and surgically resected samples. Methylated cell lines were treated with a methylation inhibitor to restore NGALR expression. Results: The expression of NGALR in ESCC was significantly higher in tumor cell membrane and cytoplasm than in normal esophageal epithelium (P < 0.01). Methylated alleles were detected in three NGALR-nonexpressing cell lines but were not detected in three NGALR-expressing cell lines. Treatment of methylated cell lines with 5-aza-2′-deoxycytidine, a methylation inhibitor, restored NGALR expression. In surgically resected samples, 31 of 77 (40.3%) primary esophageal carcinomas and 46 of 77 (59.7%) paired normal tissues contained methylated NGALR alleles (P < 0.05). Conclusions: Our results suggest that NGALR hypomethylation contributes to its expression in esophageal carcinomas and that this overexpression may play a role in the pathogenesis of esophageal carcinomas.

To investigate transcriptional regulatory properties of DNA sequence upstream of the ezrin gene promoter in nasopharyngeal carcinoma CNE2 cells.A series of reporter gene expression vectors carrying ezrin-1541/-706 sequence were constructed. In forward or reverse orientation, the ezrin -1541/-706 segment was located upstream of the luc gene in pGL3-Basic, upstream of the ezrin promoter or SV40 promoter, or downstream of the luc gene controlled by ezrin promoter or SV40 promoter. These plasmids were transfected into CNE2 cells for luciferase assay.In CNE2 cells, when the ezrin -1541/-706 was located upstream of luc gene in pGL3-Basic in the forward orientation, it exhibited transcriptional activation about 50% of ezrin promoter; while this transactivation nearly abolished when this segment was reversed. When this segment was located upstream of the ezrin promoter or SV40 promoter in the forward orientation, it dramatically increased luciferase expression. However, the transcriptional enhancement disappeared when this segment was located upstream of promoters in the reverse orientation, or downstream of reporter genes in the forward or reverse orientation.In CNE2 cells, the DNA sequence upstream of the ezrin promoter could exhibit transcriptional activation and enhancement, in a position- and orientation-dependent manner.

We previously demonstrated that the VIL2 -87/+134 region exhibited promoter activity in some human cells, and a region further upstream of this promoter might contain an enhancer. However, the properties and location of this VIL2 enhancer remain unclear. In this study, we cloned the VIL2 -1541/-706 segment and investigated its transcriptional regulatory properties via luciferase assays in transiently transfected HEK-293 cells (human embryonic kidney cells). The VIL2 -1541/-706 was found to exhibit promoter activity. Furthermore, when this segment was located upstream of the VIL2 or SV40 (simian virus 40) promoters in the forward orientation, the expression levels of luciferase were dramatically enhanced. However, this transcriptional enhancement disappeared when this segment was located upstream of the promoter in the reverse orientation or downstream of the reporter gene in the forward or reverse orientation. In deletion experiments, we found several potential regulatory regions within the VIL2 -1541/-706. When these regions were separately located upstream of the VIL2 or SV40 promoters, only the -1297/-1186 considerably enhanced the activity of these promoters. Although the other regulatory regions exhibited significant transcriptional regulation in deletion experiments, they weakly enhanced VIL2 promoter activity and/or did not regulate SV40 promoter activity. These results suggest that the DNA sequence upstream of the VIL2 promoter functions as an enhancer in a position- and orientation-dependent manner, and the VIL2 -1297/-1186, which acts as a key enhancer, probably regulates VIL2 transcription in combination with other potential regulatory regions located upstream of the VIL2 promoter.

The chloramphenicol-resistant cassette with short shared sequences of ptsG gene on both ends was PCR-generated from plasmid pKF3 and ligated to pMD18-T to construct pMD18-PC. The sdh gene for sorbose dehydrogenase was generated from plasmid pQE60-SDH and inserted into pMD18-PC, then pMD18-PC-SDH was constructed. It was digested with Pvu II and the target fragment ptsG1-cat-sdh-ptsG2 was recovered and electroporated into Escherichia coli JM109/pKD46. Homologous-recombination between linear DNA cassettes and Escherichia coli chromosomes took place by Red recombination. The detection result showed that the integron JM109s was of sorbose dehydrogenase activity. The PCR products assay using the upstream and downstream sequences of ptsG gene as primers and JM109s genomic DNA as template, indicated that sdh gene had been integrated at the ptsG gene site in Escherichia coli.

Because of the fluid-filled lungs in the fetus, the ultrasound beam can penetrate to the root of the pulmonary artery perpendicularly. Using M-mode echocardiography, the following dimensions were measured: the pulmonary and aortic valve excursion in 19 fetuses, and the pulmonary and aortic root internal diameter in 70 fetuses, between 18 and 42 weeks, menstrual age. The measured dimensions were then correlated with the biparietal diameter. The correlation coefficients for the measurements ranged from 0.873 to 0.892. Regression analysis showed that the best fit of the data was a linear model from which the 5% and 95% confidence limits were derived for individual predictions of the arterial dimensions. The ratios of the pulmonary/aortic valve excursion and the pulmonary/aortic internal diameter were approximately 1 : 1. These results are of potential value in the prenatal detection of great arterial valve or root diseases.