Targeting MYO1B impairs tumorigenesis via inhibiting the SNAI2/cyclin D1 signaling in esophageal squamous cell carcinoma.

Myosin-related proteins play an important role in cancer progression. However, the clinical significance, biological functions, and mechanisms of myosin 1B (MYO1B), in esophageal squamous cell carcinoma (ESCC) remain unclear. The clinical relevance of MYO1B, SNAI2, and cyclin D1 in ESCC was determined by immunohistochemistry, Oncomine, and GEPIA databases. The oncogenic roles of MYO1B were determined by CCK8, colony formation assays, wound healing, and Transwell assay. MYO1B, SNAI2, and cyclin D1 at mRNA and protein levels in ESCC cells were detected by qPCR and Western blot analysis. In our study, we found that MYO1B expression was increased in ESCC tissue samples and correlated with tumor stage, TNM stage, and poor outcomes. Functional assays indicated that depletion of MYO1B impaired oncogenesis, and enhanced chemosensitivity in ESCC. Bioinformatic analysis and mechanistic studies illustrated that SNAI2 was a key downstream effector of MYO1B. Suppression of MYO1B downregulated expression of SNAI2, thereby inhibiting the SNAI2/cyclin D1 pathway. Furthermore, a selective inhibitor of cyclin D1 activation reversed siMYO1B cells overexpressing SNAI2-elicited aggressive phenotypes of ESCC cells. MYO1B positively correlated with SNAI2 and cyclin D1 in ESCC samples, and higher SNAI2 expression was also associated with poor prognosis in ESCC patients. Our finding demonstrated that MYO1B activates the SNAI2/cyclin D1 pathway to drive tumorigenesis and cisplatin cytotoxicity in ESCC, indicating that MYO1B is a potential therapeutic target for patients with ESCC.

Leptin Silencing Attenuates Lipid Accumulation through Sterol Regulatory Element-Binding Protein 1 Inhibition in Nasopharyngeal Carcinoma.

Leptin is a crucial regulator of metabolism and energy homeostasis in mammals. Many studies have investigated the impacts of leptin on human cancers, such as proliferation and metastasis. However, the mechanisms underlying leptin-mediated regulation of lipid metabolism in nasopharyngeal carcinoma (NPC) remain incompletely understood. In the current study, leptin downregulation ameliorated lipid accumulation, triglyceride, and cholesterol levels. Mechanistically, diminished leptin by siRNA not only inhibited sterol regulatory element-binding protein 1 (SREBP1), a master regulator of lipid metabolism, at the mRNA and protein levels, but also reduced SREBP1 downstream target expressions, such as fatty acid synthase (FASN) and stearoyl-CoA desaturase-1 (SCD1), in NPC cells. In addition, leptin expression could modulate the promoter activity of SREBP1. We also found that pharmacological inhibition of poly-ADP ribose polymerase-γ (PPAR-γ) resulted in increased SREBP1 expression in leptin-depleted NPC cells. Functionally, SREBP1 overexpression overcame the effects of leptin-silencing attenuated triglyceride level, cholesterol level and cell survival in NPC cells. Taken together, our results demonstrate that leptin is an important regulator of lipid metabolism in NPC cells and might could be a potential therapeutic target for treatment of NPC patients.

An actin-binding protein ESPN is an independent prognosticator and regulates cell growth for esophageal squamous cell carcinoma.

BACKGROUND: ESPN (Espin), an actin filament-binding protein, plays an important role in regulating the organization, dimensions, dynamics, and signaling capacities of the actin filament-rich, microvillus-type specializations that mediate sensory transduction in various mechanosensory and chemosensory cells. Recent few studies show that ESPN regulates metastasis and cell proliferation in melanoma. However, the significance of ESPN in other cancers such as esophageal squamous cell carcinoma (ESCC) remains largely unknown. METHODS: Immunohistochemistry was performed in 169 patients with ESCC and correlated with clinicopathological features and survival. The functional role of ESPN in ESCC cells was determined by ESPN-mediated siRNA. RESULTS: Univariate analyses showed that high ESPN expression was associated with inferior overall survival (P = 0.005) and disease-free survival (P = 0.035). High ESPN expression was an independent prognosticator in multivariate analysis for overall survival (P = 0.009, hazard ratio = 1.688) and disease-free survival (P = 0.049, hazard ratio = 1.451). The 5-year overall survival rates were 30% and 54% in patients with high and low expression of ESPN, respectively. Inhibition of endogenous ESPN in ESCC cells decreased ESCC growth by reducing cell proliferating rates. CONCLUSIONS: High ESPN expression is independently associated with poor prognosis in patients with ESCC and downregulation of ESPN inhibits ESCC cell growth. Our results suggest that ESPN may be a novel therapeutic target for patients with ESCC.

The Prognostic Significance of Histone Demethylase UTX in Esophageal Squamous Cell Carcinoma.

The dysregulation of the ubiquitously transcribed TPR gene on the X chromosome (UTX) has been reported to be involved in the oncogenesis of several types of cancers. However, the expression and significance of UTX in esophageal squamous cell carcinoma (ESCC) remains largely undetermined. Immunohistochemistry was performed in 106 ESCC patients, and correlated with clinicopathological features and survival. The functional role of UTX in ESCC cells was determined by UTX-mediated siRNA. Univariate analyses showed that high UTX expression was associated with superior overall survival (OS, p = 0.011) and disease-free survival (DFS, p = 0.01). UTX overexpression was an independent prognosticator in multivariate analysis for OS (p = 0.013, hazard ratio = 1.996) and DFS (p = 0.009, hazard ratio = 1.972). The 5-year OS rates were 39% and 61% in patients with low expression and high expression of UTX, respectively. Inhibition of endogenous UTX in ESCC cells increased cell viability and BrdU incorporation, and decreased the expression of epithelial marker E-cadherin. Immunohistochemically, UTX expression was also positively correlated with E-cadherin expression. High UTX expression is independently associated with a better prognosis in patients with ESCC and downregulation of UTX increases ESCC cell growth and decreases E-cadherin expression. Our results suggest that UTX may be a novel therapeutic target for patients with ESCC.

Suppression of Aurora-A-FLJ10540 signaling axis prohibits the malignant state of head and neck cancer.

BACKGROUND: Head and neck cancer (HNC) is a highly invasive cancer. Aurora-A has been reported for a number of malignancies. However, the identity of downstream effectors responsible for its aggressive phenotype in HNC remains underinvestigated. METHODS: The mRNA and protein expression levels of Aurora-A and FLJ10540 were assessed in HNC specimens and cell lines using RT-qPCR, western blot, Oncomine, and microarray database analysis. The downstream molecular mechanisms of Aurora-A were confirmed by RT-qPCR, western blot, luciferase reporter, confocal microscopy analyses, immunoprecipitation, colony formation, cell viability, and xenograft model. Cellular functions in response to Aurora-A-modulated downstream targets such as FLJ10540 and MMPs were examined in vitro and in vivo, including cell growth, motility and chemosensitivity. Aurora-A/FLJ10540/MMPs expression was determined in cancer and adjacent normal tissues from HNC patients by immunohistochemistry approach. RESULTS: In the current study, Aurora-A exhibited similar gene expression profiles with FLJ10540 by using accessibly public microarray and Oncomine database analysis, raising the possibility that these molecules might coordinately participate in cancer progression and metastasis of HNC. These two molecules connection were also examined in cell lines and tissues of HNC. Aurora-A overexpression could not only bind to the promoter of FLJ10540 to induce FLJ10540 expression, but also increase both mRNA and protein levels of MMP-7 and MMP-10 in HNC cells. Conversely, depletion of Aurora-A expression by using siRNA or Aurora-A kinase inhibitor, MLN8237, suppressed FLJ10540, MMP-7 and MMP-10 mRNA and protein expressions in vitro and in vivo. In addition, the FLJ10540-PI3K complex was destroyed by inhibition the Aurora-A kinase activity. Forced overexpression of FLJ10540 in Aurora-A-depleted or in MLN8237-treated HNC cells attenuated the effect on cytotoxicity to cisplatin. Elevated Aurora-A expression in HNC cells led to the characteristics of more aggressive malignancy, including enhanced chemoresistance and increased the abilities of proliferation, migration and invasion, which was required for FLJ10540/MMP-7 or FLJ10540/MMP-10 expressions. Finally, immunohistochemical analysis of human HNC specimens showed a significant positively correlation among Aurora-A, FLJ10540, MMP-7 and MMP-10 expressions. CONCLUSION: Together, our findings define a novel mechanism by which Aurora-A promotes cell malignancy, with potential implications for understanding the clinical action of Aurora-A.

Overexpression of Rap-1A indicates a poor prognosis for oral cavity squamous cell carcinoma and promotes tumor cell invasion via Aurora-A modulation.

The functions of Rap-1A in oral carcinogenesis are largely unexplored. In this study, we examined the expression of Rap-1A at different malignant stages of oral cavity squamous cell carcinoma (OCSCC). Semiquantitative RT-PCR, quantitative RT-PCR, and Western blotting were used to evaluate Rap-1A mRNA and protein expressions, respectively, in paired OCSCC patient specimens. To determine the possible correlation between Rap-1A expression and various clinical characteristics, 256 samples from patients with OCSCC were evaluated by immunohistochemical staining. Strong Rap-1A expression was a significant prognostic marker and predictor of aggressive OCSCC. The overall and disease-specific 5-year survival rates were significantly correlated with strong expression of Rap-1A (P < 0.001). Functionally, overexpressed Rap-1A could promote oral cancer cell migration and invasion by Transwell chambers and wound healing assay. Conversely, the suppression of Rap-1A expression using Rap-1A-mediated siRNA was sufficient to decrease cell motility. Furthermore, our data also illustrated that Aurora-A could not only induce mRNA and protein expressions of Rap-1A for enhancing cancer cell motility but also co-localize and form a complex with Rap-1A in the oral cancer cell line. Finally, immunohistochemical staining, indirect immunofluorescence, and Western blotting analysis of human aggressive OCSCC specimens revealed a significantly positive correlation between Rap-1A and Aurora-A expression. Taken together, our results suggest that the Aurora-A/Rap-1A pathway is associated with survival, tumor progression, and metastasis of OCSCC patients.

Midkine neurite growth-promoting factor 2 expression as a potential prognostic marker of adjuvant therapy in head and neck squamous cell carcinoma.

OBJECTIVE: The prognostic function of neurite growth-promoting factor 2 (Midkine (MK)) in adjuvant treatment of head and neck squamous cell carcinoma (HNSCC) is unclear. This study examined whether MK expression may predict treatment response and survival in resectable HNSCC patients. METHODS: In this retrospective study, MK expression in 144 HNSCC patients was analyzed by immunohistochemistry. A subset of patients (n = 10) had MK expression levels analyzed by western blot and semi-quantitative reverse transcription polymerase chain reaction. Data were analyzed using the Log-rank test and α = 0.05. RESULTS: Expression of MK was associated with poorer five-year progression-free and overall survival rates in HNSCC patients (p = 0.002). CONCLUSION: MK might play an important role in the progression of HNSCC and may be a useful prognostic factor.

An integrated analysis of dysregulated SCD1 in human cancers and functional verification of miR-181a-5p/SCD1 axis in esophageal squamous cell carcinoma.

Esophageal squamous cell carcinoma (ESCC), one of the most lethal cancers, has become a global health issue. Stearoyl-coA desaturase 1 (SCD1) has been demonstrated to play a crucial role in human cancers. However, pan-cancer analysis has revealed little evidence to date. In the current study, we systematically inspected the expression patterns and potential clinical outcomes of SCD1 in multiple human cancers. SCD1 was dysregulated in several types of cancers, and its aberrant expression acted as a diagnostic biomarker, indicating that SCD1 may play a role in tumorigenesis. We used ESCC as an example to demonstrate that SCD1 was dramatically upregulated in tumor tissues of ESCC and was associated with clinicopathological characteristics in ESCC patients. Furthermore, Kaplan-Meier analysis showed that high SCD1 expression was correlated with poor progression-free survival (PFS) and disease-free survival (DFS) in ESCC patients. The protein-protein interaction (PPI) network and module analysis by PINA database and Gephi were performed to identify the hub targets. Meanwhile, the functional annotation analysis of these hubs was constructed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. Functionally, the gain-of-function of SCD1 in ESCC cells promoted cell proliferation, migration, and invasion; in contrast, loss-of-function of SCD1 in ESCC cells had opposite effects. Bioinformatic, QPCR, Western blotting and luciferase assays indicated that SCD1 was a direct target of miR-181a-5p in ESCC cells. In addition, gain-of-function of miR-181a-5p in ESCC cells reduced the cell growth, migratory, and invasive abilities. Conversely, inhibition of miR-181a-5p expression by its inhibitor in ESCC cells had opposite biological effects. Importantly, reinforced SCD1 in miR-181a-5p mimic ESCC transfectants reversed miR-181a-5p mimic-prevented malignant phenotypes of ESCC cells. Taken together, these results indicate that SCD1 expression influences tumor progression in a variety of cancers, and the miR-181a-5p/SCD1 axis may be a potential therapeutic target for ESCC treatment.

FLJ10540 is associated with tumor progression in nasopharyngeal carcinomas and contributes to nasopharyngeal cell proliferation, and metastasis via osteopontin/CD44 pathway.

BACKGROUND: Nasopharyngeal carcinoma (NPC) is well-known for its highly metastatic characteristics, but little is known of its molecular mechanisms. New biomarkers that predict clinical outcome, in particular the ability of the primary tumor to develop metastatic tumors are urgently needed. The aim of this study is to investigate the role of FLJ10540 in human NPC development. METHODS: A bioinformatics approach was used to explore the potentially important regulatory genes involved in the growth/metastasis control of NPC. FLJ10540 was chosen for this study. Two co-expression strategies from NPC microarray were employed to identify the relationship between FLJ10540 and osteopontin. Quantitative-RT-PCR, immunoblotting, and immunohistochemistry analysis were used to investigate the mRNA and protein expression profiles of FLJ10540 and osteopontin in the normal and NPC tissues to confirm microarray results. TW01 and Hone1 NPC cells with overexpression FLJ10540 or siRNA to repress endogenous FLJ10540 were generated by stable transfection to further elucidate the molecular mechanisms of FLJ10540-elicited cell growth and metastasis under osteopontin stimulation. RESULTS: We found that osteopontin expression exhibited a positive correlation with FLJ10540 in NPC microarray. We also demonstrated comprehensively that FLJ10540 and osteopontin were not only overexpressed in NPC specimens, but also significantly correlated with advanced tumor and lymph node-metastasis stages, and had a poor 5-year survival rate, respectively. Stimulation of NPC parental cells with osteopontin results in an increase in FLJ10540 mRNA and protein expressions. Functionally, FLJ10540 transfectant alone, or stimulated with osteopontin, exhibited fast growth and increased metastasis as compared to vehicle control with or without osteopontin stimulation. Conversely, knockdown of FLJ10540 by siRNA results in the suppression of NPC cell growth and motility. Treatment with anti-CD44 antibodies in NPC parental cells not only resulted in a decrease of FLJ10540 protein, but also affected the abilities of FLJ10540-elicited cell growth and motility in osteopontin stimulated-NPC cells. CONCLUSIONS: These findings suggest that FLJ10540 may be critical regulator of disease progression in NPC, and the underlying mechanism may involve in the osteopontin/CD44 pathway.

Aberrant miR-874-3p/leptin/EGFR/c-Myc signaling contributes to nasopharyngeal carcinoma pathogenesis.

BACKGROUND: Leptin is important in physiological and pathological functions in various cancers, however, the significance and mechanisms of leptin in nasopharyngeal carcinoma remain ambiguous. METHODS: Leptin expression was analyzed by QPCR, immunohistochemistry, Western blotting, and TCGA database. The impact of gain- or loss-of-function of leptin were determined by MTT, colony formation, wound healing, and Transwell assays in NPC cells, and by a xenograft tumor model. Leptin-modulated glucose consumption and lactate production were assessed by ELISA. Furthermore, leptin-regulated signaling pathways were examined by QPCR and Western blotting assays. The immunoprecipitation assay was conducted to determine interaction between leptin and EGFR. In addition, miR-874-3p-regulated leptin expression was evaluated using bioinformatics, QPCR, luciferase assay, AGO2-RIP assay, and Western blotting. RESULTS: In this study, we found that leptin was highly expressed in the sera and tumor tissues of patients with NPC, and elevated leptin expression was associated with advanced clinical features and poor prognosis. Functional assays demonstrated that leptin remarkably promoted NPC cell growth, motility, and glycolysis in vitro and in vivo. Mechanistically, leptin associated with EGFR, resulting in enhanced cell growth through the regulation of cell-cycle related markers, glycolysis-related genes, and EGFR/AKT/c-Myc signaling. Moreover, leptin potentiated the invasive capacity of NPC cells by promoting EMT. We further explored that miR-874-3p influenced leptin-mediated NPC progression. Overexpression of miR-874-3p prevented cell growth, motility, glucose consumption, and lactate production in NPC cells, whereas miR-874-3p inhibition had the opposite effects. AGO-RIP assays confirmed that Argonaute 2 (AGO2), a protein associated with miR-874-3p, regulated leptin expression in NPC cells. The rescue assays indicated that inhibition of leptin suppressed the effects of miR-874-3p inhibitor. In clinical specimens, miR-874-3p was negatively correlated with leptin. CONCLUSIONS: Leptin may serve as a novel prognostic factor and potential therapeutic target for patients with NPC. In addition, a newly discovered regulatory axis of leptin/EGFR/AKT/c-Myc can provide a novel therapeutic strategy for NPC.

DRP1 contributes to head and neck cancer progression and induces glycolysis through modulated FOXM1/MMP12 axis.

Abnormal DRP1 expression has been identified in a variety of human cancers. However, the prognostic potential and mechanistic role of DRP1 in head and neck cancer (HNC) are currently poorly understood. Here, we demonstrated a significant upregulation of DRP1 in HNC tissues, and that DRP1 expression correlates with poor survival of HNC patients. Diminished DRP1 expression suppressed tumor growth and metastasis in both in vitro and in vivo models. DRP1 expression was positively correlated with FOXM1 and MMP12 expression in HNC patient samples, suggesting pathological relevance in the context of HNC development. Moreover, DRP1 depletion affected aerobic glycolysis through the downregulation of glycolytic genes, and overexpression of MMP12 in DRP1-depleted cells could help restore glucose consumption and lactate production. Using ChIP-qPCR, we showed that DRP1 modulates FOXM1 expression, which can enhance MMP12 transcription by binding to its promoter. We also showed that miR-575 could target 3'UTR of DRP1 mRNA and suppress DRP1 expression. Collectively, our study provides mechanistic insights into the role of DRP1 in HNC and highlights the potential of targeting the miR-575/DRP1/FOXM1/MMP12 axis as a novel therapy for the prevention of HNC progression.

Insulin-like growth factor 1 mediates 5-fluorouracil chemoresistance in esophageal carcinoma cells through increasing survivin stability.

Insulin-like growth factor 1 (IGF-1) inhibits 5-fluorouracil (5-Fu)-induced apoptosis in esophageal carcinoma cells; however, the mechanisms for IGF-1-induced 5-Fu chemoresistance remain unknown. In the human esophageal carcinoma cell line, CE48T/VGH, we show that IGF-1 up-regulated survivin expression at the post-transcriptional level and this up-regulation is mediated by both the PI3-K/Akt and casein kinase 2 signaling pathways. We then examine whether IGF-1-induced 5-Fu chemoresistance is mediated through up-regulation of survivin. Ectopic expression of survivin inhibits 5-Fu-induced apoptosis; furthermore, the abolition of survivin expression sensitizes cells to 5-Fu treatment and prevents the anti-apoptotic function of IGF-1 in esophageal carcinoma cell lines. We also found that ectopic expression of survivin or treatment with IGF-1 inhibits the release of Smac/DIABLO and caspases activation after 5-Fu treatment. Our results strongly suggest that IGF-1 inhibits 5-Fu induced apoptosis through increasing survivin levels, which prevents Smac/DIABLO release and blocks the activation of caspases. Therefore, up-regulation of IGF-1 and survivin would seem to be responsible for 5-Fu chemoresistance in esophageal cancer patients and these factors may be the valuable predictors of 5-Fu chemoresistance in esophageal carcinoma.

High ERCC1 expression predicts cisplatin-based chemotherapy resistance and poor outcome in unresectable squamous cell carcinoma of head and neck in a betel-chewing area.

BACKGROUND: This study was to evaluate the effect of excision repair cross-complementation group 1(ERCC1) expression on response to cisplatin-based induction chemotherapy (IC) followed by concurrent chemoradiation (CCRT) in locally advanced unresectable head and neck squamous cell carcinoma (HNSCC) patients. METHODS: Fifty-seven patients with locally advanced unresectable HNSCC who received cisplatin-based IC followed by CCRT from January 1, 2006 through January 1, 2008. Eligibility criteria included presence of biopsy-proven HNSCC without a prior history of chemotherapy or radiotherapy. Immunohistochemistry was used to assess ERCC1 expression in pretreatment biopsy specimens from paraffin blocks. Clinical parameters, including smoking, alcohol consumption and betel nuts chewing, were obtained from the medical records. RESULTS: The 12-month progression-free survival (PFS) and 2-year overall survival (OS) rates of fifty-seven patients were 61.1% and 61.0%, respectively. Among these patients, thirty-one patients had low ERCC1 expression and forty-one patients responded to IC followed by CCRT. Univariate analyses showed that patients with low expression of ERCC1 had a significantly higher 12-month PFS rates (73.3% vs. 42.3%, p < 0.001) and 2-year OS (74.2 vs. 44.4%, p = 0.023) rates. Multivariate analysis showed that for patients who did not chew betel nuts and had low expression of ERCC1 were independent predictors for prolonged survival. CONCLUSIONS: Our study suggest that a high expression of ERCC1 predict a poor response and survival to cisplatin-based IC followed by CCRT in patients with locally advanced unresectable HNSCC in betel nut chewing area.

Fibulin-3 is associated with tumour progression and a poor prognosis in nasopharyngeal carcinomas and inhibits cell migration and invasion via suppressed AKT activity.

Nasopharyngeal carcinoma (NPC) is known for its highly metastatic character. Recent advances in diagnosis and treatment have not improved the high mortality rate that is attributable to early metastasis. Although several biomarkers correlate with metastasis and prognosis, the molecular mechanisms of NPC development and progression remain unclear. We demonstrate comprehensively that fibulin-3 is down-regulated in NPC. Loss of fibulin-3 expression is significantly correlated with advanced tumour and lymph node-metastasis stages, and indicates a poor 5-year survival rate. Functionally, fibulin-3 has the ability to suppress cell migration and invasion in NPC cancer cells by decreasing the activity of phospho-AKT. Conversely, its depletion by fibulin-3-mediated siRNAs may elevate phospho-AKT activity and significantly enhance the ability of NPC cancer cells to migrate and invade. Consistent with this negative association between fibulin-3 and phospho-AKT, their expression levels are inversely correlated in NPC specimens by immunohistochemical analysis. Thus, lower fibulin-3 expression is an important indicator of poor survival. It may also contribute to the development of new therapeutic strategies to block the PI3K/AKT pathway in NPC cancer cells.

Tumor-Associated Microbiota in Esophageal Squamous Cell Carcinoma.

Important evidence indicates the microbiota plays a key role in esophageal squamous cell carcinoma (ESCC). The esophageal microbiota was prospectively investigated in 18 patients with ESCC and 11 patients with physiological normal (PN) esophagus by 16S rRNA gene profiling, using next-generation sequencing. The microbiota composition in tumor tissues of ESCC patients were significantly different from that of patients with PN tissues. The ESCC microbiota was characterized by reduced microbial diversity, by decreased abundance of Bacteroidetes, Fusobacteria, and Spirochaetes. Employing these taxa into a microbial dysbiosis index demonstrated that dysbiosis microbiota had good capacity to discriminate between ESCC and PN esophagus. Functional analysis characterized that ESCC microbiota had altered nitrate reductase and nitrite reductase functions compared with PN group. These results suggest that specific microbes and the microbiota may drive or mitigate ESCC carcinogenesis, and this study will facilitate assigning causal roles in ESCC development to certain microbes and microbiota.

Downregulation of Notch3 links TIMP3 inhibition to suppress aggressive phenotypes of pancreatic ductal adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC), one of the most deadly digestive cancers, has a poor 5-year survival rate and is resistant to chemotherapeutic agents, such as gemcitabine. Notch3 plays an important role in cancer progression, and its expression facilitates chemoresistance in cancers. This study examined the clinical significance of Notch3 and explored the mechanisms through which it may affect disease progression in PDAC. We found Notch3 to be upregulated in PDAC patients in whom it correlated with lymph node stage and poor survival. In vitro and in vivo, functional assays indicated that silencing Notch3 could suppress the growth, migration, invasion of PDAC cells and sensitize PDAC cells to gemcitabine. QPCR array, which was performed to elucidate the Notch3-regulated pathway, revealed that inhibition of Notch3 decreased the transcription and secretion of TIMP3 in PDAC cells. Overexpression of TIMP3 reversed the impaired growth, migration, invasion, and chemosensitivity induced by Notch3 silencing. We also found a positive correlation between Notch3 mRNA expression and TIMP3 expression in patients with PDAC. We concluded that blocking Notch3/TIMP3 pathway could considered a potentially new therapeutic strategy for treating PDAC.

Combination of microarray profiling and protein-protein interaction databases delineates the minimal discriminators as a metastasis network for esophageal squamous cell carcinoma.

Microarray profiling of 15 adjacent normal/tumor-matched esophageal squamous cell carcinoma (ESCC) specimens identified 40 up-regulated and 95 down-regulated genes. Verification of the microarray measurement by quantitative real-time reverse transcription PCR in the same set of samples as well as an additional 15 normal/tumor-matched samples revealed >95% consistency. These signatures can also be used to classify a recently reported ESCC microarray dataset. Moreover, these molecular signatures were used as templates to elucidate their corresponding protein-protein interaction (PPI) networks using the PPI databases, POINT and POINeT. As a result, 18 genes, of which six were not disclosed in the initial expression profile analysis, were found to be able to serve as the minimal discriminators for distinguishing ESCC tumors from normal specimens. Of these discriminators, ten (BGN, COL1A1, COL1A2, MMP9, CD44, FN1, TGFBI, PXN, SPARC and VWF) were associated with tumor metastasis and formed a highly interactive network with the first four molecules as 'hubs'. Our study not only reveals how novel insights can be obtained from gene expression profiling, but also highlights a group of highly interacting genes associated with metastasis in ESCC.

ELF-1 expression in nasopharyngeal carcinoma facilitates proliferation and metastasis of cancer cells via modulation of CCL2/CCR2 signaling.

Background: Nasopharyngeal carcinoma (NPC) is a prevalent malignant tumor in Southeast Asia. The management of NPC has remained a challenge until now. ELF-1 is a member of the ETS family of transcription factors that regulate genes involved in cellular growth. ELF-1 expression has been reported in various cancers and is required for tumor growth and angiogenesis; however, its function in NPC remains unclear. In the present study, we characterized the role and underlying mechanism of ELF-1 in NPC. Methods: The biological functions of ELF-1 in NPC cells such as proliferation, migration, invasion, and drug resistance were investigated using MTT, BrdU incorporation, and Transwell assays. To gain more insight into the mechanism of ELF-1 in NPC, we analyzed CCL2/CCR2 signaling by Western blotting, ELISA, siRNAs, and CCR2 antagonist. Results: Gain-of-function of ELF-1 in TW01 and TW04 cells promoted NPC cell proliferation, BrdU incorporation, migration, invasion and cisplatin resistance. By contrast, knockdown of ELF-1 produced opposite results. Overexpression of ELF-1 enhanced the expression of CCL2 via binding to its promoter region and increased the level of the extracellular matrix protein CCL2 in cell culture medium. ELF-1 expression also modulated the downstream targets of CCL2/CCR2 signaling. Most importantly, ELF-1-induced NPC malignant phenotypes were abrogated by a CCR2 inhibitor, implying that the CCL2/CCR2 signaling axis was involved in ELF-1-mediated regulation in NPC. Conclusion: Our data suggest that ELF-1 plays an oncogenic role in NPC development associated with the CCL2/CCR2 signaling pathway and may therefore be a potential target for NPC therapy.

JMJD3 expression is an independent prognosticator in patients with esophageal squamous cell carcinoma.

BACKGROUND: The Jumonji-domain containing 3 has diverse roles in multiple cancers. Here, we investigated its prognostic significance in esophageal squamous cell carcinoma. METHODS: By using immunohistochemistry, the Jumonji-domain containing 3 expression was examined in 109 surgically resected esophageal squamous cell carcinomas and correlated with treatment outcome. The functional role of Jumonji-domain containing 3 in esophageal squamous cell carcinoma cells was determined by Jumonji-domain containing 3-mediated small interfering ribonucleic acid. RESULTS: Univariate analysis showed that Jumonji-domain containing 3 overexpression was associated with inferior overall survival (P = .004) and disease-free survival (P = .002). In a multivariate comparison, Jumonji-domain containing 3 overexpression remained independently associated with worse overall survival (P = .017, hazard ratio = 1.898) and disease-free survival (P = .011, hazard ratio = 1.901). The 5-year overall and disease-free survival rates were 66% and 58% in patients with a low expression of Jumonji-domain containing 3 and 34% and 27% in patients with overexpression of Jumonji-domain containing 3. Silencing Jumonji-domain containing 3 in esophageal squamous cell carcinoma cells inhibited cell growth rate and bromodeoxyuridine incorporation ability. In contrast, a gain of function of Jumonji-domain containing 3 promoted esophageal squamous cell carcinoma cell proliferation. Furthermore, Jumonji-domain containing 3 expression contributes to Ras/MEK pathway. CONCLUSION: Jumonji-domain containing 3 overexpression was independently associated with poor prognosis in patients with esophageal squamous cell carcinoma. In vitro, Jumonji-domain containing 3 expression regulated esophageal squamous cell carcinoma cell growth. These results may further elucidate the role of Jumonji-domain containing 3 in esophageal squamous cell carcinoma and provide a potential new therapeutic approach for patients with esophageal squamous cell carcinoma.

Metformin disrupts malignant behavior of oral squamous cell carcinoma via a novel signaling involving Late SV40 factor/Aurora-A.

Conventional therapeutic processes in patient with OSCC are associated with several unfavorable effects leading to patients with poor survival rate. Metformin has been shown to protect against a variety of specific diseases, including cancer. However, the precise roles and mechanisms underlying the therapeutic effects of metformin on OSCC remain elusive. In the current study, in vitro and xenograft model experiments revealed that metformin inhibited growth and metastasis of oral cancer cells. Importantly, metformin-restrained tumorigenesis of oral cancer was accompanied with strong decrease of both Aurora-A and Late SV40 Factor (LSF) expressions. Furthermore, LSF contributed to Aurora-A-elicited malignancy behaviors of oral cancer via binding to the promoter region of Aurora-A. A significant correlation was observed between LSF and Aurora-A levels in a cohort of specimens of oral cancer. These findings showed that a novel LSF/Aurora-A-signaling inhibition supports the rationale of using metformin as potential OSCC therapeutics.