Clinicopathological significance of PI3K,Akt and survivin expression in gastric cancer

Background

Gastric cancer is the second leading cause of cancer-related deaths worldwide, and is characterized by invasion and metastasis. Increasing attention is being focused on discovering molecular markers for diagnosis and prognosis. Our objective was to evaluate PI3K, Akt and survivin protein expression in gastric cancer, and their correlations with clinicohistological features and prognosis in patients with gastric cancer.

Methods

Tissue samples were obtained from 70 patients with gastric cancer patients and 20 patients with normal gastric mucosa. The protein levels of PI3K, Akt and survivin were evaluated by immunohistochemistry. Statistical analyses were performed to establish the correlations between their expressions and patients’ clinicopathologic characteristics.

Results

The positive expression rates of PI3K, Akt and survivin were significantly higher in the gastric cancer tissues compared to normal gastric mucosa (P < 0.05). Expression levels of PI3K, Akt and survivin proteins were significantly correlated with TNM stage, differentiation grade, lymph node metastasis and metastases to other organs (P < 0.05). Cooperative relationships were identified between PI3K and Akt, and PI3K and survivin (P < 0.01), suggesting the involvement of the PI3K/Akt/survivin signaling pathway in the tumorigenesis of gastric cancer.

Conclusions

Protein expression of PI3K, Akt and survivin were significantly associated with the development, progression and metastasis of gastric cancer and may have value as diagnostic and prognostic markers in gastric cancer.     

Upregulation of the TPX2 gene is associated with enhanced tumor malignance of esophageal squamous cell carcinoma

Purpose

To explore the expression of TPX2 and its significance in esophageal squamous cell carcinoma (ESCC) tissue and approach relationship between the TPX2 and clinicopathological characteristic of esophageal squamous cell carcinoma.

Method

RT-PCR and immunohistochemical staining were used to compare the expression of TPX2 in 62 esophageal squamous cell carcinoma, 31 atypical hyperplasia and 62 normal esophageal mucosa.

Results

In ESCC, atypical hyperplasia and in normal mucous membrane tissues, the positive rate of TPX2 protein expression was 85.5% (53/62), 51.6% (16/31) and 4.8% (3/62); the positive rate of TPX2 mRNA expression was 65.5% (40/62), 35.5 (11/31) and 4.83% (3/62). The expression of TPX2 protein and mRNA were correlated with invasive depth and lymphatic metastasis of ESCC (P < 0.01).

Conclusions

Overexpression of TPX2 may be risk factor of lymph node in esophageal carcinoma, and maybe a potential biomarker for early diagnosis and prognosis of esophageal squamous cell carcinoma.     

Paeoniflorin suppress NF-κB activation through modulation of IκBα and enhances 5-fluorouracil-induced apoptosis in human gastric carcinoma cells

Objective

We sought to determine whether paeoniflorin enhances 5-fluorouracil-induced apoptosis in human gastric carcinoma cells, and, if so, to determine the relationship between this apoptosis and NF-κB activation.

Methods

Paeoniflorin was diluted to different concentrations and added to gastric carcinoma cells (SGC-7901) at different times. Western blot was used to test the expression of NF-κB in nuclear and IκBα, p-IκBα, IKKα in cytoplasm. Further, the intranuclear expression of NF-κB was confirmed by ELISA assay. The impact of paeoniflorin and 5-fluorouracil on cell apoptosis of gastric carcinoma cells was estimated by flow cytometry.

Results

Paeoniflorin revealed dramatic inhibition of NF-κB activity in the nuclei of the cells. The inhibition pattern of NF-κB was exhibited in a time- and dose-dependent manner, which was confirmed by Western blot and ELISA. Decreased nuclear translocation of NF-κB induced by paeoniflorin was found by preventing IκBα phosphorylation. Moreover, 5-fluorouracil-induced cell apoptosis was promoted by paeoniflorin in gastric carcinoma cells.

Conclusions

Paeoniflorin can inhibit NF-κB activity of SGC-7901 cells, and enhance 5-fluorouracil-induced apoptosis of gastric carcinoma cells.     

Expression of livin in gastric cancer and induction of apoptosis in SGC-7901 cells by shRNA-mediated silencing of livin gene

Background

Because of increased resistance to apoptosis in tumor cells, inhibition of specific anti-apoptotic factors may provide a rational approach for the development of novel therapeutic strategies. Livin, a novel inhibitor of apoptosis protein family, has been found to be expressed in various malignancies and is suggested to have poorly prognostic significance. However, no data are available concerning the significance of livin in gastric cancer. In this study, we detected the expression of livin in human gastric carcinoma and investigated the apoptotic susceptibility of SGC – 7901 cell by shRNA-mediated silencing of the livin gene.

Methods

The mRNA and protein expression of livin were analyzed by RT-PCR and western blot assay. The relationship between livin expression and clinical pathologic parameters was investigated. The small interfering RNA eukaryotic expression vector specific to livin was constructed by gene recombination, and the nucleic acid was sequenced. Then it was transfected into SGC-7901 cells by Lipofectamin 2000. RT-PCR and Western blot assay were used to validate gene-silencing efficiency of livin in SGC-7901 cells. Stable clones were obtained by G418 screening. The cell apoptosis was assessed by flow cytometry (FCM). Cell growth state and 50 % inhibition concentration (IC50) of 5-FU and cisplatin was determined by MTT method.

Results

The expression of livin mRNA and protein were detected in 19 of 40 gastric carcinoma cases (47.5%) and SGC-7901 cells. No expression of livin was detected in tumor adjacent tissues and benign gastric lesion. The positive correlation was found between livin expression and poor differentiation of tumors as well as lymph node metastases (P < 0.05). Four small interfering RNA eukaryotic expression vector specific to livin were constructed by gene recombination. And one of them can efficiently decrease the expression of livin, the inhibition of the gene was not less than 70% (P < 0.01). The recombinated plasmids were extracted and transfected gastric cancer cells. The stable clones were obtained by G418 screening, and were amplified and cultured. When livin gene was silenced, the reproductive activity of the gastric cancer cells was significantly lower than the control groups(P < 0.05). The study also showed that IC50 of 5-Fu and cisplatin on gastric cancer cells treated by shRNA was decreased and the cells were more susceptible to proapoptotic stimuli (5-Fu and cisplatin) (P < 0.01).

Conclusions

Livin is overexpressed in gastric carcinoma with a relationship to tumor differentiation and lymph node metastases, which is suggested to be one of the molecular prognostic factors for some cases of gastric cancer. ShRNA can inhibit livin expression in SGC-7901 cells and induce cell apoptosis. Livin may serve as a new target for apoptosis-inducing therapy of gastric cancer.     

Renal cell carcinoma-adjacent tissues enhance mobilization and recruitment of endothelial progenitor cells to promote the invasion of the neoplasm

Aims

The aim of this study was to detect the levels of CD34⁺/Flk-1⁺ endothelial progenitor cells (EPCs) in renal cell carcinoma (RCC)-adjacent tissues and explore the correlation of RCC-adjacent tissues EPCs and tumor invasion.

Methods

An orthotopic renal tumor model was successfully established. At days 7, 12, 17 and 21, eight mice were put to death respectively. Tumor diameters were measured and RCC-adjacent tissues were collected. The percentage of EPCs within the kidney mononuclear cell population was detected. The expression levels of Stromal cell-derived factor-1 (SDF-1), vascular endothelial growth factor (VEGF) and their receptors CXCR4, Flk-1 mRNA and protein were probed respectively. And then, mean microvascular density (MVD) was examined.

Results

EPC numbers in RCC-adjacent tissues were significantly higher than those in control groups. The ratios of EPCs were increased gradually, and so were tumor diameters. The levels of SDF-1 and VEGF were also increased gradually, but significantly reduced compared with control group at each time point. In addition, CXCR4 and Flk-1 expression were decreased gradually.

Conclusions

Our investigation suggested that EPCs in RCC-adjacent tissues play an important role in early stage RCC invasion, involving the promotion on angiogenesis through releasing several angiogenic factors.     

Lgr5 promotes cancer stemness and confers chemoresistance through ABCB1 in colorectal cancer

Introduction

Chemotherapy failure is a major problem in patients with advanced colorectal carcinoma (CRC). Leucine-rich repeat-containing G-protein-coupled receptor 5 (Lgr5) is a well-established target gene of the Wnt pathway and is a bona fide marker of CRC cancer stem cells (CSCs). Our previous study showed that CRC patients with higher Lgr5 level are associated with poor response to 5-fluoracil-based treatment. In this study, we investigated the mechanisms underlying Lgr5-associated chemoresistance in cancer stem cells derived from cultured CRC cells.

Materials and methods

Cancer stem cells were isolated from CRC cell lines by spheroid culture. The effect of Lgr5 on CRC cancer stem cell was investigated using both gain- and loss-of-function approaches. Stemness property was evaluated using sphere formation assay, side population analysis, and stem cell marker expression. Lgr5 and ABCB1 expression in CRC tissues was determined using immunohistochemical staining.

Results

Forced expression of Lgr5 increased the CRC sphere-forming efficiency and spheroid size while depletion of Lgr5 reduced the stem cell property in cultured CRC cells. Over-expression of Lgr5 also reduced the sensitivity of cultured CRC cells, including adherent and spheroids, towards 5-fluoracil and oxalipatin. In addition, Lgr5 positively regulates the expression of ABCB1 in both adherent and spheroid CRC cells. Finally, in human CRC tissues, higher expression levels of Lgr5 were associated with higher ABCB1 expression.

Conclusions

The present study demonstrated that Lgr5 plays an active role in promoting the cancer stem cell property and that Lgr5 confers chemoresistance to CRC cells via ABCB1 induction.     

Expression of estrogen-metabolizing enzymes and estrogen receptors in cholelithiasis gallbladder

Background

Estrogen exposure is a risk factor for gallstone disease (cholelithiasis), which often leads to chronic inflammation (cholecystitis). Studies in various estrogen-sensitive tissues showed that key enzymes involved in the inactivation and activation of estrogens as well as expression of estrogen receptors α and β determine the amount of active estrogen. In estrogen-sensitive tissues, e.g. the female breast, estrone sulfate (E1S), present at high concentrations in the circulation, is converted into the biologically active estrone (E1) by steroid sulfatase (STS) and again reverted into E1S by estrogen sulfotransferase (SULT1E1) providing a local estrogen storage.

Aims

To assess whether this might also apply for gallbladder epithelia, we determined expression of these two enzymes and of ERα and ERβ in 15 cholelithiasis specimens from tissues with/or without inflammation.

Methods

Quantitative (Real-time) PCR and immunofluorescence were used as methods.

Results

We demonstrate mRNA expression of SULT1E1, STS, and ERα in all specimens with mean enrichment of 3.53- vs. 1.72-fold (n.s.), 3.5- vs. 0.91-fold (n.s.), and 3.04- vs. 1.6-fold (n.s.) in the inflammatory and non-inflammatory groups, respectively. Although high expression levels were seen in many specimens (means 4.88-fold vs. 5.77-fold), ERβ mRNA was below the detection limit in two specimens from cholecystitis patients. To further investigate this varying expression pattern of ERβ, immunohistological studies were performed, which indeed showed low expression levels of ERβ in the damaged mucosa, while in specimens with well preserved mucosa, high ERβ levels were seen in the cytosol and in the nucleus.

Conclusion

The data show expression of an estrogen network of activating STS and inactivating SULT1E1. Together with ERα and ERβ, these enzymes could regulate estrogen concentrations in human gallbladder.     

Correlation Between Aquaporin 4 Expression and Different DWI Parameters in Grade I Meningioma

Purpose

Diffusion-weighted imaging (DWI) measures water diffusion in biological tissues. Cellular water transport depends on aquaporins (AQPs). The expression of aquaporins might differ in several pathologic disorders. Therefore, the aim of this study was to evaluate the associations between AQP4 expression and different DWI parameters in meningioma.

Procedures

Twenty-three patients with meningioma grade I were included in this retrospective study. DWI was obtained with three b values (0; 500; 1000) using a 1.5-T device. ADC_mean, ADC_min, ADC_max, and true diffusion coefficients (D) were obtained in every patient. Aquaporin 4 expression was quantified immunohistochemically in four immunoreactivity levels.

Results

The estimated DWI parameters (mean value ± standard deviation, 10^?3 mm² s^?1) of the tumors were as follows: ADC_min 0.67 ± 0.16, ADC_mean 0.94 ± 0.23, ADC_max 1.29 ± 0.50, and D 0.65 ± 0.23. The mean level of the AQP4 expression was 2.02 ± 0.75 points. A statistically significant correlation between AQP4 expression and ADC_max was identified (r = 0.508, p = 0.013). No significant correlations between AQP4 and other DWI parameters were found.

Conclusions

A clear correlation between AQP4 expression and ADC_max values in grade I meningioma was identified. There were no significant correlations between AQP4 expression and other DWI parameters, such as ADC_min, ADC_mean, and D.

     

水通道蛋白在肿瘤细胞中的表达及意义

目的探讨水通道蛋白AQP1-AQP9,AQP11及AQP12在多种肿瘤细胞系中的表达并探讨其意义。方法利用RT-PCR方法对小鼠乳腺癌细胞系4T1、mmt和lewis肺癌细胞系(LLC)表达水通道情况进行初步分析。结果4T1细胞表达AQP5、AQP7及AQP11,AQP5只有少量表达,后两者表达水平较高;在lewis肺癌(LLC)中有AQP7,AQP8及AQP11表达,其中AQP7和AQP11表达较高;在mmt细胞中AQP3、AQP4、AQP7及AQP11均被检出有表达,AQP7表达程度较高。结论肿瘤细胞表达水通道蛋白是一普遍现象,可能与肿瘤细胞易转移和高度增殖等特性有关。深入研究水通道蛋白在肿瘤细胞增殖及迁移中的作用,将为肿瘤的发生、发展及转移提供新的机理。     

Peritumoral Brain Edema in Meningiomas Depends on Aquaporin-4 Expression and Not on Tumor Grade,Tumor Volume,Cell Count,or Ki-67 Labeling Index

Purpose

The aim of this study was to investigate to which degree the peritumoral brain edema in patients with meningiomas depends on aquaporin-4 (AQP4) expression, tumor grade, tumor volume, Ki-67 expression, and cell count.

Procedures

Thirty-three patients (25 women, 8 men; mean age 56.6 ± 16.0 years) with an intracranial meningioma underwent a standardized magnetic resonance (MR) examination prior to surgical resection. Edema indices (EIs) and tumor volumes were measured on the MR images. Tumor grade was classified according to the World Health Organization, and the proliferation index was estimated on Ki-67 antigen-stained specimens. Tumor cell count was evaluated. Eighteen specimens were stained for AQP4 expressioon.

Results

Significant intergroup differences between AQP4 expression grades and EIs were observed (P = 0.03), and a positive correlation was detected between EIs and AQP4 expression grades (r = 0.54; P < 0.05). A ROC analysis with EI as a test variable revealed an AUC of 0.77 (95 % CI 0.55–0.99) for the prediction of a moderate-to-strong AQP4 expression. An EI ≥1.5 predicted a moderate-to-high AQP4 expression with a sensitivity of 77 % and a specificity of 60 %. EI values of 2.2 and 3.5 reached sensitivity/specificity values of 69/80 % and 54/100 %, respectively. The AQP4 expression did not show any significant correlations with tumor grading, tumor volume, Ki-67 expression, or cell count. Moreover, we observed no significant positive or negative correlations between the EI and tumor grading (P = 0.7), tumor volume (P = 0.19), Ki-67 index (P = 0.9), and cell count (P = 0.34).

Conclusion

Peritumoral brain edema in patients with meningiomas may depend on AQP4 expression grades and not on tumor grade, tumor volume, Ki-67 expression, and cell count. The amount of edema predicted AQP4 expressions with moderate-to-good sensitivity and specificity.

     

MOR1 Expression in Gastric Cancer: A Biomarker Associated With Poor Outcome

Background

At present, the expression of MOR1 and its function in gastric cancer remains unclear with evidence suggesting that it is to be involved in tumor progression and metastasis. The study was to assess the clinicopathologic relevance and prognostic value of MOR1 expression in gastric cancer.

Methods

Real‐time quantitative RT‐PCR and immunohistochemical staining were used to detect MOR1 expression in primary gastric cancerous surgical specimens and adjacent nontumorous tissues.

Results

High MOR1 expression was detected in cancerous tumor compared with their adjacent nontumorous tissues. In addition, the chi‐square test revealed that high MOR1 expression was significantly correlated with depth of invasion (p = 0.006), lymph node metastasis (p = 0.001), distant metastasis (p = 0.017), and TNM staging (p = 0.027). Moreover, Kaplan–Meier analysis revealed a significant association between MOR1 expression and overall survival. High expression of MOR1 was identified as an independent and significant predictor gene of reduced postoperative survival.

Conclusion

We conclude that MOR1 expression may be a useful biomarker for better prediction of the clinical outcome and management of gastric cancer patients.     

Is there a correlation between HPV and urinary bladder carcinoma?

Aims

To detect human papilloma virus (HPV) infection, p21 oncogene, DNA content of urothelial cells in different bladder lesions with and without schistosomiasis and to correlate them with histopathological grade and stage.

Methods

Eighty-five patients were enrolled: 25 chronic cystitis and 60 malignant bladder lesions; 15 schistosomal squamous cell carcinoma (SQCC), 45 urothelial carcinoma (transitional cell carcinoma TCC) schistosomal and non-scistosomal. Ten healthy individuals served as controls. Genotyping of HPV 6/11 and 16/18 were done using in situ hybridization and p21 protein expression by Immunohistochemical technique in formalin-fixed, paraffin-embedded tissues. DNA content of urothelial cells were stained with felugen stains and measured using Automated Image analysis System.

Results

HPV DNA 6/11 and 16/18 expression was increased from cases of schistosomal cystitis with dysplasia to TCC with schistosomiasis compared to TCC and SQCC. The expression increased with statistical significance in invasive TCC and high-grade compared with superficial and low grade. Over-expression of p21 in invasive TCC group was compared with superficial TCC, high-grade TCC was compared low grade and TCC was compared with SQCC. Almost all cases of TCC associated with schistosomiasis exhibit aneuploid histogram compared to SQCC and all invasive TCC exhibited aneuploid histograms.

Conclusions

Both HPV infection and p21 gene abnormalities may contribute to bilharzial bladder carcinogenesis. DNA image cytometric features may predict stage progression in TCC. Expression of p21, DNA HPV 6/11 and 16/18 may be used as biological markers of bladder carcinoma.     

The effect of endostatin and gemcitabine combined with HIFU on the animal xenograft model of human pancreatic cancer

Objective

To investigate the influence of the recombinant human endostatin and gemcitabine combined with HIFU on the mouse xenograft model of pancreatic cancer.

Methods

Use human pancreatic cancer cell line PANC-1 to set up the mouse xenograft model, then randomized into four arms. Each arm was treated with gemcitabine, endostatin, gemcitabine combined with endostatin and normal saline respectively. Observe the volume of the tumor, the serum VEGF level and MVD in the tumor tissue among the different arms. All mice were treated with HIFU, then pathological examination was done.

Results

The tumor volume, serum VEGF level and MVD in the combined-therapy arm are all lower than the monotherapy arms and the control arm. The coagulation necrosis occurred in tumors after HIFU treatment.

Conclusion

Endostatin and gemcitabine has better effect than gemcitabine or endostatin monotherapy on the animal xenograft model of human pancreatic cancer. HIFU combined with chemotherapy and/or targeted therapy may enhance the effect for pancreatic cancer.     

Chemokine-dependent T cell migration requires aquaporin-3–mediated hydrogen peroxide uptake

Chemokine-dependent trafficking is indispensable for the effector function of antigen-experienced T cells during immune responses. In this study, we report that the water/glycerol channel aquaporin-3 (AQP3) is expressed on T cells and regulates their trafficking in cutaneous immune reactions. T cell migration toward chemokines is dependent on AQP3-mediated hydrogen peroxide (H₂O₂) uptake but not the canonical water/glycerol transport. AQP3-mediated H₂O₂ transport is essential for the activation of the Rho family GTPase Cdc42 and the subsequent actin dynamics. Coincidentally, AQP3-deficient mice are defective in the development of hapten-induced contact hypersensitivity, which is attributed to the impaired trafficking of antigen-primed T cells to the hapten-challenged skin. We therefore suggest that AQP3-mediated H₂O₂ uptake is required for chemokine-dependent T cell migration in sufficient immune response.Regulated T cell migration and trafficking are of crucial importance for both steady-state T cell homeostasis and active immune responses. Although naive T cells constitutively circulate between the blood and secondary lymphoid organs in a state of immune surveillance, antigen-encountered T cells selectively migrate to extralymphoid sites to exert their secondary response to antigens (Mora and von Andrian, 2006; Pittet and Mempel, 2008). The mechanistic basis of regulated T cell trafficking involves the differential expression of adhesion molecules and chemokine receptors of naive and activated T cells (Campbell et al., 2003; Schaerli and Moser, 2005; Viola et al., 2006). The naive T cells express the LN homing receptor L-selectin (CD62L) and CCR7, enabling them to preferentially migrate to the secondary lymphoid organs (Campbell et al., 1998; Mora and von Andrian, 2006). In contrast, effector T cells express CCR4 and CCR10 instead of CD62L and CCR7, enabling them to migrate to peripheral nonlymphoid tissues, such as the gut and skin, in response to the chemokines CCL17, CCL22, and CCL27 (Campbell et al., 1999; Reiss et al., 2001). Such chemokine-dependent T cell migration requires actin-dependent changes in cell morphology and mobility, which are regulated by the Rho family GTPases, including Cdc42, Rac1, and RhoA (Burkhardt et al., 2008; Tybulewicz and Henderson, 2009).Aquaporins (AQPs) are a family of highly conserved transmembrane channels that transport water and, in some cases, small solutes such as glycerol. Currently, 13 AQPs have been identified in mammals (AQP0–12). Numerous studies have demonstrated the fundamental importance of AQPs and have described their functions in several organs and physiological pathways, such as AQP1–3 in the urinary concentrating system, AQP1 in angiogenesis, AQP7 in obesity, and AQP4 in neuromyelitis optica and brain edema (Rojek et al., 2008; Verkman, 2009; Carbrey and Agre, 2009). More recently, some AQPs, including AQP3 and AQP8, have been found to mediate membrane hydrogen peroxide (H₂O₂) uptake, which is used for intracellular signaling in mammalian cells (Miller et al., 2010). Despite their importance in various biological systems, to date, AQPs have not been shown to be involved in adaptive immunity, a process in which specialized lymphocytes at different developmental stages precisely mediate protection against pathogens to maintain homeostasis. Importantly, because previous studies have shown that AQPs regulate cell migration and proliferation in some mammalian cells (Verkman, 2009), we anticipated that AQPs might play a role in the regulation of lymphocyte function.AQP3 is abundantly expressed on the plasma membrane of kidney-collecting duct principal cells and skin epidermal keratinocytes, which facilitate water and glycerol transport (Ma et al., 2000; Hara and Verkman, 2003). Our previous studies have shown that AQP3 is necessary for keratinocyte migration and proliferation, processes which have been implicated in cutaneous wound healing and tumorigenesis (Hara-Chikuma and Verkman, 2008a,b). During the course of our study, we unexpectedly found that the AQP3 protein was expressed not only by keratinocytes but also by skin-infiltrating T cells. In this study, using genetically modified AQP3 knockout mice, we have identified a novel role of AQP3 in chemokine-dependent T cell migration, which controls cutaneous immune reactions.     

Is leptin a predictive factor in patients with lung cancer?

Objectives

The aim of this study was to evaluate the expression and clinical significance of leptin in lung cancer.

Methods

126 patients with lung cancer ranged from 30 to 83 years of age were studied. Serum leptin levels were determined by ELISA. The mRNA and protein levels of leptin in normal and lung cancer tissues were measured by RT-PCR and immunohistochemistry. The relationships between leptin levels and clinicopathological factors were evaluated by Wilcoxon rank sum or Kruskal–Wallis H test.

Results

Serum leptin levels in lung cancer patients were significantly higher compared to those in controls and leptin expression in lung cancer tissue was markedly increased than that in normal lung tissue (both P < 0.050).

Conclusions

Determination of leptin levels might provide useful predictive information for lung cancer.     

Effects of prone and supine positioning on gastric residuals in preterm infants: A time series with cross-over study

Background

Few studies have examined the effect of body position on gastric residuals at different time points in feeding preterm infants. Further, the results of previous studies are inconsistent.

Objectives

To describe the changing pattern of gastric residuals over time in the prone and supine position and to examine the effects of position on gastric residuals at different feeding volumes in preterm infants.

Design

A randomized, time series with cross-over study.

Setting

A neonatal intensive care unit affiliated with a medical center in central Taiwan.

Participants

35 preterm infants who were asymptomatic for gastroesophageal reflux, other gastrointestinal diseases or other significant morbidities of any kind other than prematurity.

Methods

Infants were randomly assigned to the following treatments: 3 h in a supine position followed by 3 h in a prone position, or vice versa. Measurements of gastric residual volume were taken by syringe at 30, 60, 90, 120 and 150 min following feeding when the enteral intake was set at 50 or 100 ml/kg/day.

Results

The rate of decrease of gastric residuals in the prone and supine positions was fastest during the first half an hour post-feeding according to measurements taken at 30, 60, 90, 120 and 150 min at feeding volumes of 50 and 100 ml/kg/day (p < 001). Gastric residuals were significantly lower in the prone than in the supine position at the five measurement points.

Conclusions

Placing preterm infants in the prone position for the first half an hour post-feeding and then changing the position according to the behavior cues of the infants is suggested. This result contributes to a better understanding of the relationships between time, position, and gastric residuals; it could also help health care professionals to provide efficient feeding as well as perform the appropriate positioning of preterm infants.     

Proteomics-based identification of tumor relevant proteins in lung adenocarcinoma

Background

Lung cancer has the highest mortality rate among malignant tumors. Proteomics is a powerful tool to identify protein biomarkers. The identification of protein biomarkers associated with lung adenocarcinoma would have significance for making prognoses and designing targeted therapies.

Methods

In our study, we applied a two-dimensional difference gel electrophoresis approach coupled to a matrix-assisted laser desorption/ionization time-of-flight mass spectrometric analysis for the identification of proteins differentially expressed between lung adenocarcinoma and the paired normal bronchial epithelial tissues derived from seven patients (four of them developed distant metastasis after operation). In addition, we chose two candidate proteins and examine their expression levels in lung adenocarcinoma and adjacent normal tissues using immunohistochemistry methods, and their expression levels in serum of patients and healthy donors by ELISA.

Result

In this study, 173 proteins were found to be differentially expressed (ratio > 1.5 or < –1.5, P ≤ 0.05), and 22 of them were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Thirteen proteins were at lower levels in the lung adenocarcinoma group, while nine proteins were at higher abundance. Immunohistochemistry analysis confirmed the expression levels of the two candidate proteins. The differential expression of the candidate secreted protein in serum from lung adenocarcinoma samples and healthy controls was showed by ELISA.

Conclusion

Our results demonstrated a differential protein expression pattern for lung adenocarcinoma compared with the paired normal bronchial epithelial tissues. Further functional validation of candidate proteins is ongoing and might provide new insights in lung adenocarcinoma.     

Hypertonic saline reduces lipopolysaccharide-induced mouse brain edema through inhibiting aquaporin 4 expression

Introduction

Three percent sodium chloride (NaCl) treatment has been shown to reduce brain edema and inhibited brain aquaporin 4 (AQP4) expression in bacterial meningitis induced by Escherichia coli. Lipopolysaccharide (LPS) is the main pathogenic component of E. coli. We aimed to explore the effect of 3% NaCl in mouse brain edema induced by LPS, as well as to elucidate the potential mechanisms of action.

Methods

Three percent NaCl was used to treat cerebral edema induced by LPS in mice in vivo. Brain water content, IL-1β, TNFα, immunoglobulin G (IgG), AQP4 mRNA and protein were measured in brain tissues. IL-1β, 3% NaCl and calphostin C (a specific inhibitor of protein kinase C) were used to treat the primary astrocytes in vitro. AQP4 mRNA and protein were measured in astrocytes. Differences in various groups were determined by one-way analysis of variance.

Results

Three percent NaCl attenuated the increase of brain water content, IL-1β, TNFα, IgG, AQP4 mRNA and protein in brain tissues induced by LPS. Three percent NaCl inhibited the increase of AQP4 mRNA and protein in astrocytes induced by IL-1β in vitro. Calphostin C blocked the decrease of AQP4 mRNA and protein in astrocytes induced by 3% NaCl in vitro.

Conclusions

Osmotherapy with 3% NaCl ameliorated LPS-induced cerebral edema in vivo. In addition to its osmotic force, 3% NaCl exerted anti-edema effects possibly through down-regulating the expression of proinflammatory cytokines (IL-1β and TNFα) and inhibiting the expression of AQP4 induced by proinflammatory cytokines. Three percent NaCl attenuated the expression of AQP4 through activation of protein kinase C in astrocytes.