Hypoxia-induced SHMT2 protein lactylation facilitates glycolysis and stemness of esophageal cancer cells.

Esophageal cancer (EC) is a familiar digestive tract tumor with highly lethal. The hypoxic environment has been demonstrated to be a significant factor in modulating malignant tumor progression and is strongly associated with the abnormal energy metabolism of tumor cells. Serine hydroxymethyl transferase 2 (SHMT2) is one of the most frequently expressed metabolic enzymes in human malignancies. The study was designed to investigate the biological functions and regulation mechanisms of SHMT2 in EC under hypoxia. We conducted RT-qPCR to assess SHMT2 levels in EC tissues and cells (TE-1 and EC109). EC cells were incubated under normoxia and hypoxia, respectively, and altered SHMT2 expression was evaluated through RT-qPCR, western blot, and immunofluorescence. The biological functions of SHMT2 on EC cells were monitored by performing CCK-8, EdU, transwell, sphere formation, glucose uptake, and lactate production assays. The SHMT2 protein lactylation was measured by immunoprecipitation and western blot. In addition, SHMT2-interacting proteins were analyzed by bioinformatics and validated by rescue experiments. SHMT2 was notably upregulated in EC tissues and cells. Hypoxia elevated SHMT2 protein expression, augmenting EC cell proliferation, migration, invasion, stemness, and glycolysis. In addition, hypoxia triggered lactylation of the SHMT2 protein and enhanced its stability. SHMT2 knockdown impeded the malignant phenotype of EC cells. Further mechanistic studies disclosed that SHMT2 is involved in EC progression by interacting with MTHFD1L. Hypoxia-induced SHMT2 protein lactylation and upregulated its protein level, which in turn enhanced MTHFD1L expression and accelerated the malignant progression of EC cells.

SHMT2 regulates esophageal cancer cell progression and immune Escape by mediating m6A modification of c-myc.

BACKGROUND: In recent years, the role of altered cellular metabolism in tumor progression has attracted widespread attention. Related metabolic enzymes have also been considered as potential cancer therapeutic targets. Serine hydroxymethyltransferase 2 (SHMT2) has been reported to be upregulated in several cancers and associated with poor prognosis. However, there are few studies of SHMT2 in esophageal cancer (EC), and the related functions and mechanisms also need to be further explored. METHODS: In this study, we first analyzed SHMT2 expression in EC by online database and clinical samples. Then, the biological functions of SHMT2 in EC were investigated by cell and animal experiments. The intracellular m6A methylation modification levels were also evaluated by MeRIP. Linked genes and mechanisms of SHMT2 were analyzed by bioinformatics and rescue experiments. RESULTS: We found that SHMT2 expression was abnormally upregulated in EC and associated with poor prognosis. Functionally, SHMT2 silencing suppressed c-myc expression in an m6A-dependent manner, thereby blocking the proliferation, migration, invasion and immune escape abilities of EC cells. Mechanistically, SHMT2 encouraged the accumulation of methyl donor SAM through a one-carbon metabolic network, thereby regulating the m6A modification and stability of c-myc mRNA in a METTL3/FTO/ALKBH5/IGF2BP2-dependent way. In vivo animal experiments also demonstrated that SHMT2 mediated MYC expression by m6A-methylation modification, thus boosting EC tumorigenesis. CONCLUSION: In conclusion, our data illustrated that SHMT2 regulated malignant progression and immune escape of EC cell through c-myc m6A modification. These revealed mechanisms related to SHMT2 in EC and maybe offer promise for the development of new therapeutic approaches.

GPR97 deficiency ameliorates renal interstitial fibrosis in mouse hypertensive nephropathy.

Hypertensive nephropathy (HTN) ranks as the second-leading cause of end-stage renal disease (ESRD). Accumulating evidence suggests that persistent hypertension injures tubular cells, leading to tubulointerstitial fibrosis (TIF), which is involved in the pathogenesis of HTN. G protein-coupled receptors (GPCRs) are implicated in many important pathological and physiological processes and act as important drug targets. In this study, we explored the intrarenal mechanisms underlying hypertension-associated TIF, and particularly, the potential role of GPR97, a member of the adhesion GPCR subfamily, in TIF. A deoxycorticosterone acetate (DOCA)/salt-induced hypertensive mouse model was used. We revealed a significantly upregulated expression of GPR97 in the kidneys, especially in renal tubules, of the hypertensive mice and 10 patients with biopsy-proven hypertensive kidney injury. GPR97-/- mice showed markedly elevated blood pressure, which was comparable to that of wild-type mice following DOCA/salt treatment, but dramatically ameliorated renal injury and TIF. In NRK-52E cells, we demonstrated that knockdown of GPR97 suppressed the activation of TGF-ß signaling by disturbing small GTPase RhoA-mediated cytoskeletal reorganization, thus inhibiting clathrin-mediated endocytosis of TGF-ß receptors and subsequent Smad activation. Collectively, this study demonstrates that GPR97 contributes to hypertension-associated TIF at least in part by facilitating TGF-ß signaling, suggesting that GPR97 is a pivotal intrarenal factor for TIF progression under hypertensive conditions, and therapeutic strategies targeting GPR97 may improve the outcomes of patients with HTN.

Comparison of Clinical Efficacy of Neoadjuvant Chemoradiation Therapy Between Lower and Higher Radiation Doses for Carcinoma of the Esophagus and Gastroesophageal Junction: A Systematic Review.

PURPOSE: Neoadjuvant concurrent chemoradiation therapy (nCRT) plus surgery has been a standard treatment for locoregionally advanced esophageal cancer and carcinoma of the gastroesophageal junction (EC/GEJ), but the optimal preoperative radiation dose is still unclear. We performed this systematic review to explore the treatment efficacy and toxicity of different radiation dose levels and find an optimal dose-fractionation strategy in EC/GEJ patients receiving nCRT. METHODS AND MATERIALS: Embase and Ovid Medline were searched for articles involving cases of operable squamous and adenocarcinoma of the esophagus and GEJ in which patients received nCRT up to a dose of 50.4 Gy in 28 fractions that were published until July 2019, when the search was performed. Physical dose distributions were converted to biologically equivalent doses (BEDs), which were described in units of gray (alpha/beta). Pooled rates of overall survival (OS), progression-free survival (PFS), failure patterns, and toxicities were compared between lower-dose radiation therapy (LDRT; BED ≤48.85 Gy10) and higher-dose radiation therapy (HDRT; BED >48.85 Gy10) for patients treated with nCRT. RESULTS: A total of 110 studies with 7577 EC/GEJ patients receiving nCRT were included in this pooled analysis. Both the PFS and OS rates of patients receiving LDRT were significantly higher than those of patients receiving HDRT. Patients receiving LDRT had improved safety regarding treatment-related adverse events and lower distant failure rates than patients receiving HDRT. Utilization of modern radiation therapy (RT) techniques, including 3-dimensional conformal RT and intensity modulated RT, was associated with improved oncologic outcomes compared with 2-dimensional methods. Subgroup analysis showed that EC/GEJ patients receiving conventionally fractionated radiation to a dose of 40.0 to 41.4 Gy in 20-23 fractions showed improved OS compared with those receiving radiation above this dose. CONCLUSIONS: Based on the limited data, nCRT using BED ≤48.85 Gy10 was suitable for locoregionally advanced, resectable EC/GEJ. A total dose of 40.0 to 41.4 Gy in 20 to 23 fractions using modern RT techniques might provide the optimal therapeutic ratio.

LncRNA PCAT1 Interacts with DKC1 to Regulate Proliferation, Invasion and Apoptosis in NSCLC Cells via the VEGF/AKT/Bcl2/Caspase9 Pathway.

Long noncoding RNAs (lncRNAs) are increasingly recognized as indispensable components of the regulatory network in the progression of various cancers, including nonsmall cell lung cancer (NSCLC). The lncRNA prostate cancer associated transcript 1 (PCAT1) has been involved in tumorigenesis of multiple malignant solid tumors, but it is largely unknown that what is the role of lncRNA-PCAT1 and how it functions in the progression of lung cancer. Herein, we observed that lncRNA PCAT1 expression was upregulated in both human NSCLC tissues and cell lines, which was determined by qualitative polymerase chain reaction analysis. Then, gain-and loss-of-function manipulations were performed in A549 cells by transfection with a specific short interfering RNA against PCAT1 or a pcDNA-PCAT1 expression vector. The results showed that PCAT1 not only promoted NSCLC cell proliferation and invasion but also inhibited cell apoptosis. Bioinformatics and expression correlation analyses revealed that there was a potential interaction between PCAT1 and the dyskerin pseudouridine synthase 1 (DKC1) protein, an RNA-binding protein. Then, RNA pull-down assays with biotinylated probes and transcripts both confirmed that PCAT1 directly bounds with DKC1 that could also promote NSCLC cell proliferation and invasion and inhibit cell apoptosis. Moreover, the effects of PCAT1 and DKC1 on NSCLC functions are synergistic. Furthermore, PCAT1 and DKC1 activated the vascular endothelial growth factor (VEGF)/protein kinase B (AKT)/Bcl-2/caspase9 pathway in NSCLC cells, and inhibition of epidermal growth factor receptor, AKT, or Bcl-2 could eliminate the effect of PCAT1/DKC1 co-overexpression on NSCLC cell behaviors. In conclusion, lncRNA PCAT1 interacts with DKC1 to regulate proliferation, invasion, and apoptosis in NSCLC cells via the VEGF/AKT/Bcl-2/caspase9 pathway.

Casticin inhibits esophageal cancer cell proliferation and promotes apoptosis by regulating mitochondrial apoptotic and JNK signaling pathways.

Casticin, a flavonoid isolated from Vitex species, has been found to have anti-tumor property in multiple human cancers. The present study aimed to investigate the effect of casticin on the proliferation and apoptosis of esophageal cancer (EC) cells, and further illustrate the underlying mechanisms. In in vitro studies, human EC cell lines TE-1 and ECA-109 were treated with various concentrations of casticin (low-, middle-, and high-dose groups). The results showed that casticin dose-dependently inhibited the proliferation and clonogenicity of EC cells and induced cell cycle arrest in sub-G1 and G2 phases. Furthermore, casticin markedly enhanced EC cell apoptosis as detected by flow cytometry and Hoechst 33342 staining. The level of anti-apoptotic Bcl-2 protein was decreased, while the levels of pro-apoptotic Bax, cleaved-caspase-3, cleaved-caspase-9, and cleaved-PARP were conversely increased in casticin-treated TE-1 and ECA-109 cells. Moreover, casticin decreased the mitochondrial membrane potential and increased the release of mitochondrial cytochrome C into cytoplasm. In addition, the JNK signaling pathway was involved in casticin-medicated anti-proliferation and pro-apoptosis. Cells pretreated with SP600125, a JNK pathway inhibitor, partially abolished the effect of casticin. Finally, the anti-tumor property of casticin was confirmed in in vivo xenograft models. Overall, we provided both in vitro and in vivo evidences that casticin inhibited the proliferation and induced apoptosis of EC cells, and the anti-tumor action of casticin was mediated, in part, by the mitochondrial-dependent apoptosis and the activation of JNK signaling pathway.

Inhibition of NOB1 by microRNA-330-5p overexpression represses cell growth of non-small cell lung cancer.

MicroRNAs (miRNAs) play critical roles in the development and progression of various cancers, including non-small-cell lung cancer (NSCLC). Studies have suggested that miR-330-5p is involved in the progression of several cancers. However, the role of miR-330-5p in NSCLC remains unclear. We investigated the effect on and mechanism of miR-330-5p in the progression of NSCLC. We found that miR-330-5p was significantly downregulated in NSCLC tissues and cell lines as detected by real-time quantitative polymerase chain reaction (RT-qPCR). The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), bromodeoxyuridine (BrdU), colony formation and cell cycle assays showed that overexpression of miR-330-5p markedly inhibited cell growth. Annexin V-FITC/PI and caspase-3 activity assays showed that overexpression of miR-330-5p significantly promoted cell apoptosis of NSCLC cells. Bioinformatics analysis and dual-luciferase reporter assays confirmed NIN/RPN12 binding protein 1 (NOB1) as a target gene of miR-330-5p. RT-qPCR and Western blot analysis showed that overexpression of miR-330-5p inhibited the expression of NOB1 as well as cyclin D1 and cyclin-dependent kinase 4 in NSCLC cells. Moreover, overexpression of NOB1 markedly reversed the miR­330-5p-mediated inhibitory effect on NSCLC cell growth. Correlation analysis showed that miR­330-5p expression was inversely correlated with NOB1 mRNA expression in NSCLC tissues. Taken together, our results indicate that miR-330-5p inhibits NSCLC cell growth through downregulation of NOB1 expression. Our study suggests that miR-330-5p may serve as a potential therapeutic target for the treatment of NSCLC.

Endoscopic ultrasonography for preoperative staging of esophageal carcinoma.

OBJECTIVE: To evaluate the diagnostic value of endoscopic ultrasonography (EUS) in preoperative staging of esophageal carcinoma (EC). MATERIAL AND METHODS: A total of 86 surgical patients with EC who were confirmed by endoscopy and biopsy underwent preoperative TN staging with EUS examination. The EUS findings were compared with surgical pathologic results. RESULTS: The accuracy of EUS in T and N staging of EC was 82.6% and 84.9%, respectively. While determining whether EC invades the muscularis propria or outer membrane, EUS had the favorable sensitivity, specificity, positive predictive value and negative predictive value. The short-axis diameter of lymph nodes of 5mm had high sensitivity and negative predictive value to determine malignance with low specificity and positive predictive value. The short-axis diameter of 10mm presented the satisfactory sensitivity, specificity, positive predictive value and negative predictive value. CONCLUSION: EUS can accurately determine the TN staging of EC and provide a reliable basis for the treatment of EC.

PIK3CA gene mutations in Northwest Chinese esophageal squamous cell carcinoma.

AIM: To evaluate PIK3CA gene mutational status in Northwest Chinese esophageal squamous cell carcinoma (ESCC) patients, and examine the associations of PIK3CA gene mutations with clinicopathological characteristics and clinical outcome. METHODS: A total of 210 patients with ESCC who underwent curative resection were enrolled in this study. Pyrosequencing was applied to investigate mutations in exons 9 and 20 of PIK3CA gene in 210 Northwest Chinese ESCCs. The associations of PIK3CA gene mutations with clinicopathological characteristics and clinical outcome were examined. RESULTS: PIK3CA gene mutations in exon 9 were detected in 48 cases (22.9%) of a non-biased database of 210 curatively resected Northwest Chinese ESCCs. PIK3CA gene mutations were not associated with sex, tobacco use, alcohol use, tumor location, stage, or local recurrence. When compared with wild-type PIK3CA gene cases, patients with PIK3CA gene mutations in exons 9 experienced significantly better disease-free survival and overall survival rates. CONCLUSION: The results of this study suggest that PIK3CA gene mutations could act as a prognostic biomarker in Northwest Chinese ESCC patients.

Knockdown of DDX5 Inhibits the Proliferation and Tumorigenesis in Esophageal Cancer.

DEAD (Asp-Glu-Ala-Asp) box protein 5 (DDX5), a prototypical member of the DEAD/H-box protein family, has been involved in several human malignancies. However, the expression and biological role of DDX5 in esophageal cancer (EC) remain largely unknown. In this study, we examined the role of DDX5 in regulating EC cell proliferation and tumorigenesis and explored its possible molecular mechanism. We found that DDX5 was overexpressed in human EC cell lines. In addition, knockdown of DDX5 significantly inhibited the proliferation of EC cells in vitro and the growth of EC xenografts in vivo. Knockdown of DDX5 also suppressed the migration/invasion and epithelial-to-mesenchymal transition (EMT) phenotype in EC cells. Furthermore, we observed that knockdown of DDX5 inhibited the expression of ß-catenin, c-Myc, and cyclin D1 in EC cells. In conclusion, our findings provide the first evidence that siRNA-DDX5 inhibited the proliferation and invasion of EC cells through suppressing the Wnt/ß-catenin signaling pathway. Therefore, DDX5 may be a novel potential therapeutic target for the prevention and treatment of EC.

p38 predicts depression and poor outcome in esophageal cancer.

p38 mitogen-activated protein kinase (MAPK) signaling has been implicated in the cancer development and progression. However, the precise mechanism of this association remains unknown. The aim of the present study was to evaluate the association between p38 and cancer progression, including investigations into the effects on cell proliferation, resistance to thalidomide, indoleamine 2,3-dioxygenase (IDO) expression and prognosis in patients with esophageal cancer. The present retrospective study included patients with stage I-III esophageal cancer. A total of 228 patients with esophageal cancer were recruited to analyze the expression of phosphorylated (p)-p38 and IDO in tumor, and normal tissues through immunohistochemistry. Depression status was measured using the Zung Self-Rating Depression Scale. P38 cDNA was transfected into esophageal cancer cells to assess tumor cell viability, sensitivity to thalidomide treatment and IDO gene expression. Western blotting and flow cytometry was used to analyze protein expression alterations, and apoptosis in esophageal cancer cells. P-p38 protein was expressed in 68.9% of cancer tissues, and was significantly associated with depressive symptoms, tumor recurrence and poor survival of patients. In vitro experiments revealed that the expression of p-p38 induced esophageal cancer Eca-109 and TE-1 cell viability, and resistance to thalidomide treatment, as well as in the expression of IDO without the application of lipopolysaccharides. Further follow-up of patients revealed that depression was also an independent factor for early recurrence and overall survival rate. Altered p38 MAPK expression was associated with poor outcome in patients with esophageal cancer. p38 may be a potential biomarker for the prediction of depressive symptoms and prognosis in patients with esophageal cancer.

miR-1908 Overexpression Inhibits Proliferation, Changing Akt Activity and p53 Expression in Hypoxic NSCLC Cells.

The ribosomal protein (RP)-p53 pathway has been shown to play a key role in apoptosis and senescence of cancer cells. miR-1908 is a newly found miRNA that was reported to have prognostic potential in melanoma. However, its role and mechanism in the progression of non-small cell lung cancer (NSCLC) are largely unknown. In this study, we found that expression of miR-1908 was significantly downregulated in human NSCLC cell lines, including SK-MES-1, A549, and NCI-H460. Then the role of miR-1908 in NSCLC cell proliferation was explored. The miR-1908 mimic was transfected into NSCLC cell lines, and their proliferation was detected. MTT and Cell Titer-Blue H analyses showed that the cell proliferation was notably reduced by the miR-1908 mimic transfection. Moreover, we found the RP-p53 pathway was activated by miR-1908 mimic. Moreover, the miR-1908 inhibitor transfection had a completely opposite effect on the NSCLC cell proliferation than that of miR-1908 mimic. To explore the underlying mechanism of that, TargetScan bioinformatics server and 3'-UTR luciferase reporter assay were applied to identify the targets of miR-1908. Our results showed that AKT1 substrate 1 (AKT1S1), a newly proven suppressor of the RP-p53 pathway, was a target of miR-1908, suggesting a probable mechanism for miR-191 suppressing NSCLC cell proliferation. Our findings provide a novel molecular target for the regulation of NSCLC cell proliferation.

Downregulation of O-linked N-acetylglucosamine transferase by RNA interference decreases MMP9 expression in human esophageal cancer cells.

O-linked N-acetylglucosamine transferase (OGT) catalyzes O-linked glycosylation (O-GlcNAcylation). O-GlcNAcylation is a post-translational carbohydrate modification of diverse nuclear and cytosolic proteins by the addition of O-linked ß-N-acetylglucosamine. It was recently demonstrated that OGT and the level of O-GlcNAcylation are upregulated in esophageal cancer; however, the physiological consequences of this upregulation remain unknown. The current study reports that OGT knockdown by short hairpin RNA (shRNA) did not affect cell viability; however, cell migration in esophageal cancer Eca-109 cells was significantly reduced. OGT-specific shRNA vectors efficiently decreased the protein and mRNA levels of OGT and the RL2 level (a marker of O-GlcNAcylation levels) in Eca-109 esophageal cancer cells. In addition, colony formation and cell proliferation assays demonstrated that OGT-specific shRNA decreased the proliferation of Eca-109 cells; however, there was no significant statistical difference between OGT-specific shRNA and control shRNA. Notably, transwell assays demonstrated that the migratory ability of Eca-109 cells was significantly suppressed following knockdown of the OGT gene. Correspondingly, western blot analyses demonstrated that OGT knockdown significantly downregulated the expression of matrix metalloproteinase 9 (MMP9) in Eca-109 cells. These results suggest that OGT may promote the migration, invasion and metastasis of esophageal cancer cells by enhancing the stability or expression of MMP9.

Silencing NACK by siRNA inhibits tumorigenesis in non-small cell lung cancer via targeting Notch1 signaling pathway.

Non-small cell lung cancer (NSCLC) is the most common type of lung tumor with poor prognosis, in which the Notch signaling pathway plays an important role. Notch activation complex kinase (NACK) has been reported both as a co-activator and a target gene of the Notch pathway. However, the molecular mechanism of NACK in NSCLC still remains unknown. In this study, the expression of NACK was analyzed in 35 paired NSCLC tumor samples and 2 NSCLC cell lines. MTT assay, cell migration assay, cell invasion assay, flow cytometry assay, and xenograft model were employed to detect the effect of NACK knockdown on the cell proliferation, metastasis, invasion and apoptosis of NSCLC. The relationship between NACK and Notch1 signaling pathway in NSCLC cells was assessed by western blot and luciferase reporter assay. We found that the expression of NACK in the NSCLC tissues and lung cancer cells were significantly increased. High level of NACK expression is remarkable associated with tumor differentiation, lymphatic metastasis, clinical stage and poor survival prognosis. The interference of NACK significantly inhibited cell proliferation, invasion and metastasis through inducing apoptosis in NSCLC cells. The transcriptional activity of related Notch1 target genes were significantly suppressed resulting from NACK knockdown. This study demonstrates that interference of NACK inhibits NSCLC progression through Notch1 signaling pathway and targeting NACK may be an effective approach for NSCLC therapy.

The crucial role of miR-126 on suppressing progression of esophageal cancer by targeting VEGF-A.

BACKGROUND: miR-126 is a key regulator of oncogenic processes. It is functionally linked to cellular proliferation, survival and migration. Vascular endothelial growth factor A (VEGF-A), which is regarded as a tumorgenesis activator, could directly target miR-126 in several tumors. However, the mechanism in esophageal cancer remains unclear. METHODS AND RESULTS: In this study, the expression of miR-126 and VEGF-A were assessed in esophageal cancer tissues and esophageal cancer cell lines. We found that miR-126 has significantly lower expression in esophageal cancer tissues and esophageal cancer cell lines than in healthy tissues, while the expression of VEGF-A is high. Luciferase reporter assays were performed to investigate the relationship between VEGF-A and miR-126. We confirmed that VEGF-A is a target for miR-126. Furthermore, the proliferation of esophageal cancer cells with miR-126 overexpression and miR-126 knockdown was monitored using the MTT assay. The results showed that miR-126 could inhibit esophageal cancer cell proliferation in vitro. The effect of miR-126 was also detected in BALB/c nude mice with transplanted esophageal cancer cells. In vivo study showed that tumor growth was significantly suppressed by miR-126 overexpression. CONCLUSIONS: We believe that restoring miR-126 levels may be a promising therapeutic approach in cases of esophageal cancer.

Sequencing study on familial lung squamous cancer.

Lung cancer is the leading cause of cancer-related mortality worldwide. The majority of lung cancers are sporadic, and familial cases are extremely rare. Previous studies have mainly focused on sporadic lung cancer and identified a large quantity of driver genes. However, familial lung cancers are rarer and studied less. The present study recruited a Chinese family in which multiple members had developed lung squamous carcinoma. To find the causative mutations, whole exome sequencing was conducted using a peripheral blood sample of one lung squamous carcinoma patient, and certain variants were validated in more samples. Whole exome sequencing analysis obtained ~2.0 Gb of data (an average of 60x depth for each targeted base), and further validation experiments identified two functional variants in two cancer-related genes (c.1218delA:p.E406fs in PDE4DIP and C1342A:p.L448I in CLTCL1). This study therefore provides useful sources for the further study of hereditary lung cancer.

MicroRNA­361­5p suppresses cancer progression by targeting signal transducer and activator of transcription 6 in non­small cell lung cancer.

The incidence of non­small cell lung cancer (NSCLC) has significantly increased in China, while the prognosis of affected patients is poor. The pathogenesis of NSCLC is thought to be regulated by microRNAs (miRs). The present study used a miR array in order to determine the expression of miR­361­5p, which was significantly lower in NSCLC tissues compared with that in adjacent tissues, indicating a crucial role of miR­361­5p during the progression of NSCLC. Furthermore, the effects of transfection-induced upregulation of miR­361­5p on the NSCLC cell line H23 were assessed. Overexpression of miR­361­5p inhibited the proliferation and colony formation ability of H23 cells. In addition, apoptosis of H23 cells was induced by upregulation of miR­361­5p. Furthermore, signal transducer and activator of transcription 6 (STAT6) was confirmed as a direct target of miR­361­5p by a dual­luciferase reporter assay. Moreover, inhibition of STAT6 by small interfering RNA or miR­361­5p also decreased the expression of B-cell lymphoma extra large (Bcl-xL). In vivo, miR­361­5p significantly reduced tumor growth in a nude mouse xenograft model, and suppressed STAT6 and Bcl-xL expression. In conclusion, the present study indicated that miR­361­5p may represent a novel molecular tool for therapeutic and diagnostic strategies in NSCLC.

Expression and significance of vascular endothelial growth factor C from multiple specimen sources in esophageal squamous cell carcinoma.

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) is a common malignancy with a very poor prognosis. Vascular endothelial growth factor C (VEGF-C) plays an important role in angiogenesis and lymphangiogenesis. This study was designed to analyze the correlation of VEGF-C expression with clinicopathological features and survival in multiple specimen sources from patients with ESCC. MATERIAL AND METHODS: The expression of VEGF-C in tissues (tVEGF-C), serum (sVEGF-C), and lymph fluid (lVEGF-C) from 48 patients with ESCC was detected by different methods. RESULTS: There were significant correlations between a high level of tVEGF-C expression and tumor differentiation, tumor depth, lymph node metastasis, TNM stage and metastasis. sVEGF-C was only significantly related to lymph node metastasis, TNM stage and metastasis. The results of lVEGF-C expression were similar to those of tVEGG-C expression, but no relationship to tumor depth was found. High expression levels of tVEGF-C, sVEGF-C and lVEGF-C were significantly associated with shorter overall survival times in univariate analysis (log-rank test). CONCLUSIONS: The expression of VEGF-C in multiple specimen sources from patients with ESCC was associated with certain clinicopathological parameters. High expression of VEGF-C may be an important factor related to a poor prognosis of ESCC.

Relationships of uPA and VEGF expression in esophageal cancer and microvascular density with tumorous invasion and metastasis.

OBJECTIVE: To investigate uPA and VEGF expression in esophageal cancer and relations with tumorous invasion and metastasis. METHODS: Immunohistochemistry was used to detect uPA and VEGF expression in the normal epithelial tissue of esophageal mucosa and cancer tissue and detect CD34 labeled micrangium and analyze the relationships with clinical pathological features and tumor angiogenesis. RESULTS: Positive rates for uPA and VEGF protein expression were significantly greater in esophageal cancer than normal epithelial tissue (P < 0.05), the two being linked (P <0.05). In addition, uPA and VEGF protein expression of the high microvessel density (MVD) group was significantly lower than in the low MVD group (P < 0.05), with relation to clinical pathological staging, differentiation and lymph node metastasis (P < 0.05). CONCLUSION: In esophageal cancer tissue, uPA and VEGF proteins are overexpressed and promote tumor angiogenesis, indicative of a poor prognosis.

O-linked N-acetylglucosamine transferase (OGT) is overexpressed and promotes O-linked protein glycosylation in esophageal squamous cell carcinoma.

The aim of this present study was to explore the expression and clinical significance of O-linked N-acetylglucosamine (O-GlcNAc) transferase (OGT) and enzymatic O-linked glycosylation (O-GlcNAcation) through the addition of O-linked-ß-N-acetylglucosamine in esophageal squamous cell carcinoma. OGT expression and O-GlcNAcation in 40 samples from patients with esophageal squamous cell carcinoma was detected by immunohistochemical staining with anti-OGT antib ody and O-GlcNAc-specific antibody RL2, respectively. The relationship between pathological and clinical factors of patients was analyzed. We found that the expression of OGT was higher in esophageal squamous cell carcinoma samples compared to the normal tissues. RL2 antibody level was positively correlated with OGT expression, and the metastasis of lymph node, which means the level of O-GlcNAcation was high and related to the metastasis of lymph node in esophageal squamous cell carcinoma. In conclusion, OGT activation is the main reason for promoting the level of O-GlcNAcation in esophageal squamous cell carcinoma. O-GlcNAcylation may play an important role in esophageal squamous cell carcinoma.