The Role of the Carnitine/Organic Cation Transporter Novel 2 in the Clinical Outcome of Patients With Locally Advanced Esophageal Carcinoma Treated With Oxaliplatin.

Esophageal cancer is the ninth most common malignancy worldwide, ranking sixth in mortality. Platinum-based chemotherapy is commonly used for treating locally advanced esophageal cancer, yet it is ineffective in a large portion of patients. There is a need for reliable molecular markers with direct clinical application for a prospective selection of patients who can benefit from chemotherapy and patients in whom toxicity is likely to outweigh the benefit. The cytotoxic activity of platinum derivatives largely depends on the uptake and accumulation into cells, primarily by organic cation transporters (OCTs). The aim of the study was to investigate the impact of OCT expression on the clinical outcome of patients with esophageal cancer treated with oxaliplatin. Twenty patients with esophageal squamous cell carcinoma (SCC) were prospectively enrolled and surgical specimens used for screening OCT expression level by western blotting and/or immunostaining, and for culture of cancer cells. Sixty-seven patients with SCC who received oxaliplatin and for whom follow-up was available were retrospectively assessed for organic cation/carnitine transporter 2 (OCTN2) expression by real time RT-PCR and immunostaining. OCTN2 staining was also performed in 22 esophageal adenocarcinomas. OCTN2 function in patient-derived cancer cells was evaluated by assessing L-carnitine uptake and sensitivity to oxaliplatin. The impact of OCTN2 on oxaliplatin activity was also assessed in HEK293 cells overexpressing OCTN2. OCTN2 expression was higher in tumor than in normal tissues. In patient-derived cancer cells and HEK293 cells, the expression of OCTN2 sensitized to oxaliplatin. Patients treated with oxaliplatin who had high OCTN2 level in the tumor tissue had a reduced risk of recurrence and a longer survival time than those with low expression of OCTN2 in tumor tissue. In conclusion, OCTN2 is expressed in esophageal cancer and it is likely to contribute to the accumulation and cytotoxic activity of oxaliplatin in patients with esophageal carcinoma treated with oxaliplatin.

Low Expression of ASK1-Interacting Protein-1 Is Significantly Correlated with Tumor Angiogenesis and Poor Survival in Patients with Early Stage Non-Small Cell Lung Cancer.

OBJECTIVE: To investigate the expression of tumor suppressor protein ASK1-interacting protein-1 (AIP1) in cancer tissues of patients with early-stage non-small cell lung cancer (NSCLC) and its correlation with tumor progression, tumor angiogenesis and prognosis. METHODS: A total of 136 patients with stage I NSCLC who underwent radical resection of lung cancer in Qianfoshan Hospital of Shandong Province from January 2011 to December 2011 were enrolled. Immunohistochemistry was used to detect AIP1 protein in tumor tissues. Vascular endothelial CD34 immunohistochemical staining was used to count intratumoral microvessel density (MVD). SPSS 19.0 software was used to analyze the relationship between AIP1 protein expression and clinicopathological features, tumor angiogenesis and prognosis. RESULTS: Low expression of AIP1 was more common in tumor tissues with high MVD, and patients with low expression of AIP1 were more likely to have tumor recurrence. Multivariate analysis showed that low expression of AIP1 had predictive value for overall survival, disease-free survival, and disease-specific survival. CONCLUSION: Downregulation of AIP1 protein expression is associated with lung cancer progression, tumor angiogenesis and poor prognosis. Consequently, AIP1 may prove to be an important predictor of recovery from lung cancer and could become a new therapeutic target for lung cancer treatment.

Low expression level of ASK1-interacting protein-1 correlated with tumor angiogenesis and poor survival in patients with esophageal squamous cell cancer.

OBJECTIVE: To investigate the expression of tumor suppressor protein ASK1-interacting protein-1 (AIP1) in human esophageal squamous cell carcinoma (ESCC) and its role in tumor progression, angiogenesis, and prognosis. METHODS: A total of 117 biopsy samples were obtained from ESCC patients. None of the patients had distant metastasis before surgery, and did not receive preoperative chemotherapy or radiotherapy. Immunohistochemistry was used to detect the expression of AIP1 protein and vascular endothelial growth factor receptor 2 (VEGFR2) in ESCC specimens collected from 117 patients who underwent esophageal cancer radical surgery. Microvessel density (MVD) was evaluated by immunohistochemical staining of vascular endothelial CD34. The correlation between AIP1 protein and clinicopathological characteristics, tumor angiogenesis, and prognosis was analyzed. RESULTS: The downregulation of AIP1 protein in esophageal carcinoma tissues was detected in 63 cases. This downregulation significantly correlated with lymph node metastasis, clinicopathological staging, and tumor MVD (P<0.05). Survival analysis showed that ESCC patients with a low expression of AIP1, a high expression of VEGFR2, and a high level of MVD had a lower 5-year survival rate (P<0.05). Multivariate analysis confirmed that the downregulation of AIP1 significantly affected patient survival. CONCLUSION: The downregulation of AIP1 correlated with ESCC progression, tumor angiogenesis, and poor prognosis. AIP1 could be a promising biomarker for predicting ESCC prognosis and a potential target for anti-angiogenic therapy.

Effects of Proanthocyanidins on Intestinal Motility Disturbance Following Intestinal Ischemia/Reperfusion.

PURPOSE: To investigate the potential protective effects of Proanthocyanidins(PAs) on intestinal motility disturbance following intestinal ischemia/reperfusion (I/R). MATERIALS AND METHODS: Male rats were divided into four groups: Sham, I/R, I/R+PA100 and I/R+PA200. Sham group underwent laparotomy without ligation, the others were subjected to intestinal ischemia for 1 h and reperfusion 4 h. Rats in the I/R+PA100 group received PAs (100 mg/kg/d) for 5 days prior to I/R, while rats in the I/R+PA200 group received PAs (200 mg/kg/d). After reperfusion, using an electrophysiology instrument measured ileal slow wave. Ileal specimens were obtained to determine contractility, tissue levels of Bax, Bcl-2, and Caspase-3 and evaluate histopathological changes. In addition, blood sample was obtained to determine serum superoxide dismutase (SOD) activity and malondialdehyde (MDA) levels. RESULTS: Intestinal I/R caused severe histopathological injury including mucosal erosions, inflammatory cell infiltration, necrosis, and hemorrhage. Both PAs treatment decreased mucosal pathological impairment in comparison with the I/R group (p < .05) in light microscopic evaluations. In both PAs-treated groups, Bax and Caspase-3 expression were decreased compared to I/R group, while the Bcl-2 expression increased (p < .05), which was similarly the case for serum SOD activity demonstrated significant enhance (p < .05) and decline in MDA levels in comparison with I/R group (both p < .05). Moreover, PAs treatment was more efficient in attenuating serum MDA levels of intestinal I/R (both p < .05). And the contractile amplitude and frequency of slow wave in I/R+PA100 and I/R+PA200 groups were higher than I/R group (both p < .05). CONCLUSIONS: PAs improve intestinal motility disturbance following intestinal I/R by alleviating oxidative stress and apoptosis.

Rotenone induces apoptosis in human lung cancer cells by regulating autophagic flux.

Reactive oxygen species (ROS) are at the center of many physiological and pathological processes. ROS generated due to oxidative stress can potentiate both cancer initiation and progression. Rotenone, which is an inhibitor of the mitochondrial electron transport chain complex I, results in the activation of NOX2 and release of ROS, and has been shown to display anticancer activity through the induction of apoptosis in various cancer cells. The mechanistic link between rotenone-dependent activation of NOX2 and induction of apoptosis is still elusive. In this study, we used the human lung cancer A549 cells to study the molecular mechanism(s) involved between rotenone-dependent activation of NOX2 and impairment of autophagic machinery. We report that acute exposure to rotenone induced mild NOX2-dependnet oxidative stress, which impaired the autophagic flux, resulting in cytosolic accumulation of LC3 and p62/STSQM1. We further show that this induction occurs through the PI3K/Akt/mTORC1 signaling pathway. We furthermore show that chronic exposure to rotenone lead to excessive NOX2-dependent ROS generation, increases autophagy, and decreases p62 level via increased-autophagic flux. Taken together, this study is the first mechanistic elucidation of how rotenone can be used to potently target cancer cells without overhauling the entire cellular machinery. © 2016 IUBMB Life 68(5):388-393, 2016.

Clinicopathological and prognostic significance of metastasis-associated protein 1 expression and its correlation with angiogenesis in lung invasive adenocarcinomas, based on the 2011 IASLC/ATS/ERS classification.

Based on previous findings regarding the angiogenic activities and prognostic roles of metastasis-associated protein 1 (MTA1) in early-stage non-small cell lung cancer, the clinicopathological and prognostic significance of MTA1 protein expression, and its correlation with angiogenesis in lung invasive adenocarcinoma, were further assessed in the present study, according to the 2011 International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society classification. High protein expression levels of MTA1 were commonly observed in patients with lung invasive adenocarcinoma, and were significantly correlated with tumor size (P=0.030), lymph node metastasis (P=0.021) and microvessel density (P=0.015). Survival analysis demonstrated that patients with high protein expression levels of MTA1 exhibited significantly shorter five-year disease-free and overall survival than those patients whose protein expression levels of MTA1 were low (24.5% vs. 48.7%, P=0.001, and 34.7% vs. 59.2%, P=0.005, respectively). In addition, Cox regression multivariate analysis demonstrated that high protein expression levels of MTA1 significantly correlated with unfavorable five-year disease-free survival (P=0.024). These findings indicate that MTA1 protein expression may possess clinical potential as an indicator of progressive phenotype. Therefore, MTA1 is a promising prognostic predictor to identify subgroups of patients with high risk of relapse, and a potentially novel therapeutic target for antiangiogenesis in patients with lung invasive adenocarcinoma.

Risk patterns of subsequent primary cancers following esophagectomy in early-stage thoracic esophageal squamous cell cancer patients.

AIMS AND BACKGROUND: Subsequent primary cancers (SPCs) have been demonstrated to be the major causes of death among patients with thoracic esophageal squamous cell cancer (ESCC) negative for lymph node involvement. We designed this study to investigate clinical characteristics and risk patterns of SPCs following esophagectomy in patients with early-stage thoracic ESCC. METHODS: We retrospectively analyzed clinical factors in 512 patients with early-stage thoracic ESCC collected from 3 independent hospitals over a 10-year interval. RESULTS: The overall standard incidence rate (SIR) of SPCs was 3.84 (95% confidence interval 2.98-4.95). The most common SPCs were head and neck cancers, lung cancer, and stomach cancer. The risk patterns of SPCs varied across organs. A 3-phase risk pattern with a U-shaped curve between 2 rising phases was seen for head and neck cancers, while for the other cancers, the risk patterns all displayed as an approximately linear upward trend. It was further noted that sex, smoking habits, and cancer histories among first-degree relatives were 3 significant independent risk factors in the development of SPCs. CONCLUSIONS: We observed significant associations between early-stage ESCC and SPCs arising from anatomically adjacent sites. The different risk patterns of SPCs indicated that follow-up strategies should be established accordingly in different organs at different times, with particularly close follow-up for head and neck cancers in the first 5 years and beyond 15 years after diagnosis of ESCC.

GOLPH3, a good prognostic indicator in early-stage NSCLC related to tumor angiogenesis.

BACKGROUND: Golgi phosphoprotein-3 (GOLPH3) is implicated in cancer development and progression. The aim of this study was to evaluate the prognostic significance of GOLPH3 protein and its association with tumor angiogenesis in patients with early-stage NSCLC. MATERIALS AND METHODS: Immunohistochemistry was performed to determine GOLPH3 protein expression and allow assessment of intratumoral microvessel density (MVD) by counting CD-34 positive immunostained endothelial cells. Correlations of expression with MVD, clinicopathologic features and clinical prognosis were analyzed. RESULTS: A notably higher level of GOLPH3 expression was found in early-stage NSCC tissues at the protein level. However, we do not find any correlation between GOLPH3 expression and clinicopathologic features (p>0.05), although higher MVD was positively associated with GOLPH3 overexpression (p<0.001). Expression of GOLPH3 was found to be an independent prognostic factor in early- stage NSCLC patients, those expressing high levels of GOLPH3 exhibiting a substantially lower 5-year overall survival than GOLPH3-negative patients (adjusted HR =1.899, 95% CI: 1.021-3.532, p=0.043). CONCLUSIONS: High expression of the GOLPH3 protein is common in early-stage NSCC, and is closely associated with tumor progression, increased tumor angiogenesis, and poor survival. We conclude a possibility of its use as a diagnostic and prognostic marker in early-stage NSCC patients.

TFIIB-related factor 2 is associated with poor prognosis of nonsmall cell lung cancer patients through promoting tumor epithelial-mesenchymal transition.

In this study, we found that increased BRF2 protein expression was prevalent in NSCLC. Overexpression of BRF2 correlated with abnormal expression of E-cadherin, N-cadherin, and snail. Additionally, expression of BRF2 was found to be an independent prognostic factor in NSCLC patients. Furthermore, we showed that targeted knockdown of BRF2 expression could inhibit the migratory and invasive abilities of NSCLC cells and induced loss of the epithelial-mesenchymal transition of NSCLC cells. These results suggested that BRF2 overexpression in tumor tissues is significantly associated with the poor prognosis of NSCLC patients through promoting epithelial-mesenchymal transition (EMT) program.

LAPTM4B polymorphism is associated with non­small cell lung cancer susceptibility and prognosis.

Lysosome-associated protein transmembrane-4ß (LAPTM4B) is a novel cancer-related gene that is upregulated in many tumors, and which plays important roles in carcinogenesis. It has two alleles, LAPTM4B 1 and LAPTM4B 2. LAPTM4B 1 contains only one copy of a 19-bp sequence in the first exon, whereas LAPTM4B 2 contains two tight tandem segments. Previous studies have shown that LAPTM4B 2 is a risk factor for susceptibility and prognosis of many tumors. The present study investigated the relationship between LAPTM4B polymorphism and non-small cell lung cancer (NSCLC) susceptibility and prognosis. We identified LAPTM4B genotypes with polymerase chain reaction (PCR) in peripheral blood samples. In the adjusted multivariate logistic regression analysis, we found that LAPTM4B 1/2, LAPTM4B 2/2 exhibited 1.48-fold [95% confidence interval (CI), 1.076-2.037] and 2.855-fold (95%CI, 1.722-4.734) increases in the risk of developing NSCLC compared with non-LAPTM4B 2 carriers. Furthermore, our results showed that overall survival time and disease-free survival time of patients with LAPTM4B 2 were significantly shorter than in patients carrying LAPTM4B 1 (P=0.001 and P=0.001, respectively). In addition, multivariate Cox regression analysis revealed that LAPTM4B 2 was also an independent prognostic factor for NSCLC. These results suggest that LAPTM4B polymorphisms may be a prospective marker for evaluating the risk and prognosis of NSCLC.

TFIIB-related factor 2 over expression is a prognosis marker for early-stage non-small cell lung cancer correlated with tumor angiogenesis.

BACKGROUND: The aim of this study was to examine BRF2 expression in patients with non-small cell lung cancer (NSCLC) and explore the relationship of BRF2 protein with clinicopathologic factors, tumor angiogenesis and prognosis. METHODS: Both BRF2 protein and intratumoral microvessels were examined by immunohistochemical staining in 107 non-small cell lung cancer patients. Intratumoral microvessel density (MVD) was measured by counting CD-34 positive immunostained endothelial cells. Western blot and RT-PCR analyses were utilized to investigate the BRF2 expression status in tissues. RESULTS: A notably higher level of BRF2 expression was found in NSCLC tissues at protein levels. In addition, univariate and multivariate analysis demonstrated that BRF2 protein over-expression and high MVD were significantly associated with tumor relapse. Although BRF2 overexpression and high MVD indicated poor 5-year overall survival (p = 0.004 and p = 0.019, respectively), multivariate analysis demonstrated that only BRF2 overexpression was an independent prognostic factor for unfavorable overall survival (P = 0.021). CONCLUSIONS: BRF2 is a promising biomarker to identify individuals with poor prognostic potential and a possible target for anti-angiogenic therapy for patients with early-stage NSCLC.

Overexpression of TFIIB-related factor 2 is significantly correlated with tumor angiogenesis and poor survival in patients with esophageal squamous cell cancer.

Studies have shown that genetic activation of TFIIB-related factor 2 (BRF2) represents a unique mechanism of tumorigenesis through the increase in Pol III-mediated transcription. Several studies have shown that BRF2 is overexpressed in several types of cancer and suggest the oncogenic role of BRF2. This study aimed to examine the expression of TFIIB-related factor 2 (BRF2) in patients with esophageal squamous cell cancer (ESCC) and explore the relationship of BRF2 expression with clinicopathologic factors, tumor angiogenesis and prognosis. We found that increased BRF2 protein expression was prevalent in esophageal squamous cell cancer and was significantly associated with deeper tumor invasion (P = 0.039) and microvessel density (P = 0.007). Additionally, expression of BRF2 was found to be an independent prognostic factor in ESCC patients. Furthermore, a significant correlation between high BRF2 expression and shorter overall survival time was found in different subgroups of ESCC patients stratified by the clinical stage, T classification and lymph node metastasis. High expression of BRF2 protein is closely associated with tumor progression and angiogenesis and poor survival of ESCC. BRF2 is a promising biomarker to identify individuals with poor prognostic potential and concludes the possibility of its use as a prognostic marker in patients with ESCC.

Down-regulation of MTA1 protein leads to the inhibition of migration, invasion, and angiogenesis of non-small-cell lung cancer cell line.

Metastasis-associated protein 1 (MTA1) high expression has been detected in a wide variety of human aggressive tumors and plays important roles in the malignant biological behaviors such as invasion, metastasis, and angiogenesis. However, the specific roles and mechanisms of MTA1 protein in regulating the malignant behaviors of non-small-cell lung cancer (NSCLC) cells still remain unclear. To elucidate the detailed functions of MTA1 protein, we down-regulated the MTA1 protein expression in NSCLC cell line by RNA interference (RNAi) in vitro, and found that down-regulation of MTA1 protein significantly inhibited the migration and invasion potentials of 95D cells. Further research revealed that down-regulation of MTA1 protein significantly decreased the activity of matrix metalloproteinase-9, which could be the mechanism responsible for the inhibition of 95D cells migration and invasion. In addition, the tube formation assay demonstrated that the number of complete tubes induced by the conditioned medium of MTA1-siRNA 95D cells was significantly smaller than that of 95D cells. These findings demonstrate that MTA1 protein plays important roles in regulating the migration, invasion, and angiogenesis potentials of 95D cells, suggesting that MTA1 protein down-regulation by RNAi might be a novel therapeutic approach to inhibit the progression of NSCLC.

Diallyl trisulfide induces apoptosis and inhibits proliferation of A549 cells in vitro and in vivo.

Lung cancer is the leading cause of cancer-related mortality all over the world. In recent years, pulmonary adenocarcinoma has surpassed squamous cell carcinoma in frequency and is the predominant form of lung cancer in many countries. Epidemiological investigations have shown an inverse relationship between garlic (Allium sativum) consumption and death rate from many cancers. Diallyl trisulfide (DATS) is one of the garlic-derived compounds (also known as: organosulfer compounds, OSC). DATS can induce apoptosis and inhibit the growth of many cancer cell lines. Our study demonstrated that the apoptotic incidents induced by DATS were a mitochondria-dependent caspase cascade through a significant decrease of the anti-apoptotic Bcl-2 that resulted in up-regulation of the ratio of Bax/Bcl-2 and the activity of caspase-3, -8, and -9. Eventually, DATS induced the apoptosis and inhibited the proliferation in a concentration- and time-dependent manner. Furthermore, by establishing an animal model of female BALB/c nude mice with A549 xenografts, we found that oral gavage of DATS significantly retarded growth of A549 xenografts in nude mice without causing weight loss or any other side effects compared with the control group. All the evidence both in vitro and in vivo suggested that DATS could be an ideal anti-cancer drug.

Proteomics characterization of cytoplasmic and lipid-associated membrane proteins of human pathogen Mycoplasma fermentans M64.

Mycoplasma fermentans is a potent human pathogen which has been implicated in several diseases. Notably, its lipid-associated membrane proteins (LAMPs) play a role in immunomodulation and development of infection-associated inflammatory diseases. However, the systematic protein identification of pathogenic M. fermentans has not been reported. From our recent sequencing results of M. fermentans M64 isolated from human respiratory tract, its genome is around 1.1 Mb and encodes 1050 predicted protein-coding genes. In the present study, soluble proteome of M. fermentans was resolved and analyzed using two-dimensional gel electrophoresis. In addition, Triton X-114 extraction was carried out to enrich amphiphilic proteins including putative lipoproteins and membrane proteins. Subsequent mass spectrometric analyses of these proteins had identified a total of 181 M. fermentans ORFs. Further bioinformatics analysis of these ORFs encoding proteins with known or so far unknown orthologues among bacteria revealed that a total of 131 proteins are homologous to known proteins, 11 proteins are conserved hypothetical proteins, and the remaining 39 proteins are likely M. fermentans-specific proteins. Moreover, Triton X-114-enriched fraction was shown to activate NF-kB activity of raw264.7 macrophage and a total of 21 lipoproteins with predicted signal peptide were identified therefrom. Together, our work provides the first proteome reference map of M. fermentans as well as several putative virulence-associated proteins as diagnostic markers or vaccine candidates for further functional study of this human pathogen.

Metastasis-associated protein 1 nuclear expression is closely associated with tumor progression and angiogenesis in patients with esophageal squamous cell cancer.

BACKGROUND: The purposes of the present study were to detect the expression of metastasis-associated protein 1 (MTA1) in patients with esophageal squamous cell cancer (ESCC), and to evaluate the relevance of MTA1 protein expression to the tumor progression, angiogenesis, and prognosis. METHODS: Both MTA1 protein and intratumoral microvessels were examined by immunohistochemical staining in 131 ESCC patients who successfully underwent subtotal esophagectomy and esophagogastric anastomosis at Qilu Hospital between Jan 2004 and Dec 2005. Intratumoral microvessel density (MVD) was recorded by counting CD-34 positive immunostained endothelial cells. All statistical analyses were performed with SPSS 13.0 statistical software. RESULTS: High expression of MTA1 protein was detected in 57 cases and significantly correlated with tumor invasion depth (P = 0.041), lymph node metastasis (P = 0.021), pathologic stage (P = 0.003), and MVD (P = 0.044). Survival analysis showed that patients with MTA1 protein high expression had significantly poor overall 5-year survival (P = 0.002), and the factor found on multivariate analysis to significantly affect overall survival was only pathologic stage (P = 0.040). Further stratified survival analysis split by pathologic stage demonstrated that MTA1 protein high expression significantly predicted unfavorable prognosis among patients with pathologic stage II disease (P = 0.006). CONCLUSIONS: High expression of the MTA1 protein is common in ESCC, and is closely associated with tumor progression, increased tumor angiogenesis, and poor survival. These findings indicate that MTA1 protein has clinical potentials as a useful indicator of progressive phenotype, a promising prognostic predictor to identify patients with poor prognosis, and a potential novel therapeutic target of antiangiogenesis for patients with ESCC.

Repression of btuB gene transcription in Escherichia coli by the GadX protein.

BACKGROUND: BtuB (B twelve uptake) is an outer membrane protein of Escherichia coli. It serves as a receptor for cobalamines uptake or bactericidal toxin entry. A decrease in the production of the BtuB protein would cause E. coli to become resistant to colicins. The production of BtuB has been shown to be regulated at the post-transcriptional level. The secondary structure of 5' untranslated region of btuB mRNA and the intracellular concentration of adenosylcobalamin (Ado-Cbl) would affect the translational efficiency and RNA stability of btuB gene. The transcriptional regulation of btuB expression is still unclear. RESULTS: To determine whether the btuB gene is also transcriptionally controlled by trans-acting factors, a genomic library was screened for clones that enable E. coli to grow in the presence of colicin E7, and a plasmid carrying gadX and gadY genes was isolated. The lacZ reporter gene assay revealed that these two genes decreased the btuB promoter activity by approximately 50%, and the production of the BtuB protein was reduced by approximately 90% in the presence of a plasmid carrying both gadX and gadY genes in E. coli as determined by Western blotting. Results of electrophoretic mobility assay and DNase I footprinting indicated that the GadX protein binds to the 5' untranslated region of the btuB gene. Since gadX and gadY genes are more highly expressed under acidic conditions, the transcriptional level of btuB in cells cultured in pH 7.4 or pH 5.5 medium was examined by quantitative real-time PCR to investigate the effect of GadX. The results showed the transcription of gadX with 1.4-fold increase but the level of btuB was reduced to 57%. CONCLUSIONS: Through biological and biochemical analysis, we have demonstrated the GadX can directly interact with btuB promoter and affect the expression of btuB. In conclusion, this study provides the first evidence that the expression of btuB gene is transcriptionally repressed by the acid responsive genes gadX and gadY.

Overexpression of metastasis-associated protein 1 is significantly correlated with tumor angiogenesis and poor survival in patients with early-stage non-small cell lung cancer.

BACKGROUND: The aims of this work are to detect the expression levels of metastasis-associated protein 1 (MTA1) in patients with early-stage non-small cell lung cancer (NSCLC), and to investigate the relationship of MTA1 protein with clinicopathologic factors, tumor angiogenesis, and prognosis. METHODS: One hundred and two patients with pathologic stage I NSCLC who successfully underwent curative surgical resection were enrolled in this study. Immunohistochemical staining for MTA1 and CD34 was performed using the streptavidin-peroxidase method, and intratumoral microvessel density (MVD) was recorded by counting CD34-positive immunostained endothelial cells. All statistical analyses were performed with SPSS statistical software to determine the effects of MTA1 protein on clinicopathologic factors, tumor angiogenesis, and prognosis. RESULTS: MTA1 protein overexpression was detected in 41 cases and was significantly associated with MVD (P = 0.008). MTA1 protein overexpression and high MVD were significantly associated with tumor relapse (P = 0.004 and 0.007) and poor 5-year disease-free survival (P = 0.001 and 0.004). Patients with MTA1 protein overexpression and high MVD had significantly poor overall survival (P = 0.005 and 0.043) and disease-specific survival (P = 0.006 and 0.031) at 5 years after operation. Multivariate analysis demonstrated that MTA1 protein overexpression was an independent prognosticator for unfavorable disease-free, overall, and disease-specific survival (P = 0.011, 0.024, and 0.046). CONCLUSIONS: MTA1 protein overexpression is common in early-stage NSCLC and is significantly associated with tumor angiogenesis and poor survival. These findings suggest that MTA1 may have clinical potential as a promising predictor to identify individuals with poor prognostic potential and as a possible novel target molecule of antiangiogenic therapy for patients with early-stage NSCLC.

Blockade of JAK2 activity suppressed accumulation of ß-catenin in leukemic cells.

The Wnt/ß-catenin pathway has been implicated in leukemogenesis. We found ß-catenin abnormally accumulated in both human acute T cell leukemia Jurkat cells and human erythroleukemia HEL cells. ß-Catenin can be significantly down-regulated by the Janus kinase 2 specific inhibitor AG490 in these two cells. AG490 also reduces the luciferase activity of a reporter plasmid driven by LEF/ß-catenin promoter. Similar results were observed in HEL cells infected with lentivirus containing shRNA against JAK2 gene. After treatment with 50 µM AG490 or shRNA, the mRNA expression levels of ß-catenin, APC, Axin, ß-Trcp, GSK3α, and GSK3ß were up-regulated within 12-16 h. However, only the protein levels of GSK3ß and ß-Trcp were found to have increased relative to untreated cells. Knockdown experiments revealed that the AG490-induced inhibition of ß-catenin can be attenuated by shRNA targeting ß-TrCP. Taken together; these results suggest that ß-Trcp plays a key role in the cross-talk between JAK/STAT and Wnt/ß-catenin signaling in leukemia cells.

Expression of cytoplasmic-domain substituted epidermal growth factor receptor inhibits tumorigenicity of EGFR-overexpressed human glioblastoma multiforme.

The accumulated results of recent clinical studies have indicated that aberrant epidermal growth factor receptor (EGFR) activation due to gene amplification and/or rearrangement contributes to increased malignancy and poor prognosis in many human cancers, especially in human glioblastoma multiforme (GBM). The elevated EGFR signaling in GBM has been correlated with shorter interval to relapse and lower survival rates, even in patients treated with surgery, radiation therapy, and/or chemotherapy. Therefore, the blockade of EGFR signaling in GBM may provide an ideal alternative therapeutic strategy. In this study, two EGFR-overexpressing human GBM cell lines (i.e., DBTRG and GBM 8901) were used as a model system. We demonstrated that expression of a human EGFR (EGFRt-EGFP) chimera protein in which the cytoplasmic domain is substituted by EGFP significantly reduced the EGF-induced endogenous EGFR autophosphorylation, EGF-induced downstream extra-cellular signal-regulated kinase (ERK) and Akt signaling, and the proportion of internalized receptors in EGF stimulated cells. Furthermore, these cells' anchorage-independent growth in vitro was decreased and their tumorigenicity in vivo abrogated or strongly suppressed. Our data suggest that EGFRt-EGFP abrogates tumor growth by disrupting receptor activation via competing for EGF-like ligands, forming non-activated heterodimers with endogenous EGFR, and inhibiting the EGFR endosomal signaling by substantially diminishing receptor internalization. This treatment modality (termed 'dominant-negative EGFR therapy') and its efficacy for gliomas or other tumors are under scrutiny.