hes1-protein--human and Stomach-Neoplasms

To perform a meta-analysis to quantitatively summarize the evidence for the association between the Notch signaling pathway and gastric cancer (GC).. An electronic search of the MEDLINE, EMBASE and Chinese National Knowledge Infrastructure, which contain articles published from 1966 onwards, was conducted to select studies for this meta-analysis.. Fifteen studies with a total of 1547 gastric cancer cases and 450 controls were included in this meta-analysis. Overall, the expression of Notch1, Notch2, Delta-like 4 and Hes1 was significantly higher in tumor tissues of GC compared to normal tissues. Specifically, stratified analyses showed that significantly increased expression of Notch1 was associated with non-cardia location, > 5 cm size, diffuse type, positive lymphovascular invasion and distal metastasis. Statistically significant higher expression of Notch3 was found in diffuse type GC. Jagged1 was also significantly over-expressed in diffuse type and poor differentiation type of GC. DLL4 was significantly over-expressed in advanced T stage, N stage and TNM stage in GC patients. However, the stratified analysis showed that there was no statistically significant difference in Hes1 expression between different subgroups. Sporadic reports showed that Notch1 and Jagged1 were independent poor prognostic predictors in GC.. The Notch signaling pathway plays an important role in tumor progression of gastric cancer.

Topics: Adaptor Proteins, Signal Transducing; Basic Helix-Loop-Helix Transcription Factors; Calcium-Binding Proteins; Chi-Square Distribution; Homeodomain Proteins; Humans; Intercellular Signaling Peptides and Proteins; Jagged-1 Protein; Membrane Proteins; Neoplasm Staging; Odds Ratio; Receptor, Notch1; Receptor, Notch2; Receptor, Notch3; Receptors, Notch; Serrate-Jagged Proteins; Signal Transduction; Stomach Neoplasms; Transcription Factor HES-1

Cancer stem cells are undifferentiated cancer cells that have self-renewal ability, a high tumorigenic activity, and a multilineage differentiation potential. MicroRNAs play a critical role in regulating gene expression during carcinogenesis. Here, we investigated the role of miR-7 and the mechanism by which it is dysregulated in gastric cancer stem cells (GCSCs). The stem cell marker, CD44, was used to sort GCSCs by fluorescence-activated cell sorting. We found that CD44 (+) cells have higher invasiveness and form more number of sphere colonies than CD44 (-) cells. Quantitative real-time polymerase chain reaction (PCR) revealed that the miR-7-5p expression was remarkably downregulated in GCSCs but was significantly increased in the methionine-deprived medium. The downregulation of miR-7-5p results from the increased DNA methylation in the promoter region using the methylation-specific PCR. Overexpression of miR-7-5p reduced the formation of colony and decreased the invasion of GCSCs through targeting Smo and Hes1 and subsequent repressing Notch and Hedgehog signaling pathways in vitro. Notably, upregulating miR-7-5p inhibited the growth of tumor in the xenograft model. Hence, these data demonstrated that miR-7-5p represses GCSC invasion through inhibition of Smo and Hes1, which provides a potential therapeutic target of gastric cancer treatment.

Topics: Animals; Cell Line, Tumor; Cell Movement; Cell Proliferation; DNA Methylation; Down-Regulation; Female; Gene Expression Regulation, Neoplastic; Humans; Hyaluronan Receptors; Mice; Mice, Inbred BALB C; Mice, Nude; MicroRNAs; Neoplastic Stem Cells; Promoter Regions, Genetic; Real-Time Polymerase Chain Reaction; Signal Transduction; Smoothened Receptor; Stomach Neoplasms; Transcription Factor HES-1; Xenograft Model Antitumor Assays

Notch pathway signaling is known to promote gastric stem cell proliferation, and constitutive pathway activation induces gastric tumors via mTORC1 activation in mouse genetic models. The purpose of this study was to determine whether human gastric adenocarcinomas are similarly dependent on Notch and mTORC1 signaling for growth. Gene expression profiling of 415 human gastric adenocarcinomas in The Cancer Genome Atlas, and a small set of locally obtained gastric cancers showed enhanced expression of Notch pathway components, including Notch ligands, receptors and downstream target genes. Human gastric adenocarcinoma tissues and chemically induced mouse gastric tumors both exhibited heightened Notch and mTORC1 pathway signaling activity, as evidenced by increased expression of the NOTCH1 receptor signaling fragment NICD, the Notch target HES1, and the mTORC1 target phosphorylated S6 ribosomal protein. Pharmacologic inhibition of either Notch or mTORC1 signaling reduced growth of human gastric cancer cell lines, with combined pathway inhibition causing a further reduction in growth, suggesting that both pathways are activated to promote gastric cancer cell proliferation. Further, mTORC1 signaling was reduced after Notch inhibition suggesting that mTOR is downstream of Notch in gastric cancer cells. Analysis of human gastric organoids derived from paired control and gastric cancer tissues also exhibited reduced growth in culture after Notch or mTOR inhibition. Thus, our studies demonstrate that Notch and mTOR signaling pathways are commonly activated in human gastric cancer to promote cellular proliferation. Targeting these pathways in combination might be an effective therapeutic strategy for gastric cancer treatment.

Topics: Adenocarcinoma; Animals; Cell Line, Tumor; Cell Proliferation; Female; Gene Expression Regulation, Neoplastic; Humans; Male; Mechanistic Target of Rapamycin Complex 1; Mice; Receptor, Notch1; Receptors, Notch; Signal Transduction; Stomach Neoplasms; TOR Serine-Threonine Kinases; Transcription Factor HES-1

Gastric cancer (GC) is a global health problem because of limited treatments and poor prognosis. Annonaceous acetogenins (ACGs) has been reported to exert anti-tumorigenic effects in cancer, yet the mechanism underlying its effects on GC remains largely unknown. Notch signaling plays a critical role in cell proliferation, differentiation and apoptosis. Therefore, it may contribute to the development of GC. This study aims to explore the role of Notch2 in ACGs' activities in GC cells.. ACGs inhibited GC cells' viability in a dose dependent manner and led to cell apoptosis and cell cycle arrest in G0/G1 phase with an increased Notch2 expression. Additionally, Notch2 siRNA reduced ACGs-induced cell growth inhibition while Notch2 cDNA transfection did the opposite.. ACGs were administrated in GC cells and cell proliferation was assayed by MTS, cell apoptosis and cell cycle were detected by flow cytometry. Additionally, the expression of Notch2 and the downstream target Hes1 were identified by Western blot. Furthermore, Notch2-siRNA transfection and Notch2-cDNA were performed to investigate the role of Notch2 in the antitumor effect of ACGs.. Up-regulation of Notch2 by ACGs is a potential therapeutic strategy for GC.

Topics: Acetogenins; Apoptosis; Carcinogenesis; Cell Line, Tumor; Cell Proliferation; Cell Survival; DNA, Complementary; Flow Cytometry; G1 Phase Cell Cycle Checkpoints; Humans; Receptor, Notch2; RNA Interference; RNA, Small Interfering; Signal Transduction; Stomach Neoplasms; Transcription Factor HES-1; Transfection; Up-Regulation

Multidrug resistance (MDR) remains a major clinical obstacle in the treatment of gastric cancer (GC) since it causes tumor recurrence and metastasis. The transcription factor activator protein-2α (AP-2α) has been implicated in drug-resistance in breast cancer; however, its effects on MDR of gastric cancer are far from understood. In this study, we aimed to explore the effects of AP-2α on the MDR in gastric cancer cells selected by vincristine (VCR). Decreased AP-2α levels were markedly detected by RT-PCR and Western blot in gastric cancer cell lines (BGC-823, SGC-7901, AGS, MKN-45) compared with that in the gastric epithelial cell line (GES-1). Furthermore, we found that the expression of AP-2α in SGC7901/VCR or SGC7901/adriamycin (ADR) cells was lower than in SGC7901 cells. Thus, a vector overexpressing AP-2α was constructed and used to perform AP-2α gain-of-function studies in SGC7901/VCR cells. The decreased IC50 values of the anti-cancer drugs in sensitive and resistant cells after transfect with pcDNA3.1/AP-2α were determined in SGC7901/VCR cells by MTT assay. Moreover, flow cytometry analysis indicated that overexpressed AP-2α induced cell cycle arrest in the G0/G1 phase and promoted cell apoptosis of VCR-selected SGC7901/VCR cells. RT-PCR and Western blot demonstrated that overexpressed AP-2α can significantly induce the down-regulation of Notch1, Hes-1, P-gp and MRP1 in SGC7901/VCR cells. Similar effects can be observed when Numb (Notch inhibitor) was introduced. In addition, the intracellular ADR accumulation was markedly detected in AP-2α overexpressed or Numb cells. In conclusion, our results indicate that AP-2α can reverse the MDR of gastric cancer cells, which may be realized by inhibiting the Notch signaling pathway.

Topics: Apoptosis; ATP Binding Cassette Transporter, Subfamily B; Cell Line, Tumor; Doxorubicin; Drug Resistance, Multiple; Drug Resistance, Neoplasm; Gene Expression Regulation, Neoplastic; Humans; Multidrug Resistance-Associated Proteins; Receptor, Notch1; Stomach Neoplasms; Transcription Factor AP-2; Transcription Factor HES-1; Vincristine

Irradiation has been reported to increase radioresistance and epithelial-mesenchymal transition (EMT) in gastric cancer (GC) cells. The Notch pathway is critically implicated in cancer EMT and radioresistance. In the present study, we investigated the use of a Notch-1 inhibiting compound as a novel therapeutic candidate to regulate radiation-induced EMT in GC cells. According to previous screening, tangeretin, a polymethoxylated flavonoid from citrus fruits was selected as a Notch-1 inhibitor. Tangeretin enhanced the radiosensitivity of GC cells as demonstrated by MTT and colony formation assays. Tangeretin also attenuated radiation-induced EMT, invasion and migration in GC cells, accompanied by a decrease in Notch-1, Jagged1/2, Hey-1 and Hes-1 expressions. Tangeretin triggered the upregulation of miR-410, a tumor-suppressive microRNA. Furthermore, re-expression of miR-410 prevented radiation-induced EMT and cell invasion. An in vivo tumor xenograft model confirmed the antimetastasis effect of tangeretin as we observed in vitro. In nude mice, tumor size was considerably diminished by radiation plus tangeretin co-treatment. Tangeretin almost completely inhibited lung metastasis induced by irradiation. Tangeretin may be a novel antimetastatic agent for radiotherapy.

Topics: Animals; Basic Helix-Loop-Helix Transcription Factors; Calcium-Binding Proteins; Cell Cycle Proteins; Cell Line, Tumor; Epithelial-Mesenchymal Transition; Flavones; Gene Expression Regulation, Neoplastic; Homeodomain Proteins; Humans; Intercellular Signaling Peptides and Proteins; Jagged-1 Protein; Lung Neoplasms; Membrane Proteins; Mice; MicroRNAs; Radiation Tolerance; Receptor, Notch1; Serrate-Jagged Proteins; Stomach Neoplasms; Transcription Factor HES-1

To determine the underlying mechanisms of action and influence of Xiaotan Sanjie (XTSJ) decoction on gastric cancer stem-like cells (GCSCs).. The gastric cancer cell line MKN-45 line was selected and sorted by FACS using the cancer stem cell marker CD44; the stemness of these cells was checked in our previous study. In an in vitro study, the expression of Notch-1, Hes1, Vascular endothelial growth factor (VEGF), and Ki-67 in both CD44-positive gastric cancer stem-like cells (GCSCs) and CD44-negative cells was measured by Western blot. The effect of XTSJ serum on cell viability and on the above markers was measured by MTT assay and Western blot, respectively. In an in vivo study, the ability to induce angiogenesis and maintenance of GCSCs in CD44-positive-MKN-45- and CD44-negative-engrafted mice were detected by immunohistochemical staining using markers for CD34 and CD44, respectively. The role of XTSJ decoction in regulating the expression of Notch-1, Hes1, VEGF and Ki-67 was measured by Western blot and real-time polymerase chain reaction.. CD44(+) GCSCs showed more cell proliferation and VEGF secretion than CD44-negative cells in vitro, which were accompanied by the high expression of Notch-1 and Hes1 and positively associated with tumor growth (GCSCs vs CD44-negative cells, 2.72 ± 0.25 vs 1.46 ± 0.16, P < 0.05) and microvessel density (MVD) (GCSCs vs CD44-negative cells, 8.15 ± 0.42 vs 3.83 ± 0.49, P < 0.001) in vivo. XTSJ decoction inhibited the viability of both cell types in a dose-dependent manner in vitro. Specifically, a significant difference in the medium- (82.87% ± 6.53%) and high-dose XTSJ groups (77.43% ± 7.34%) was detected at 24 h in the CD44(+) GCSCs group compared with the saline group (95.42% ± 5.76%) and the low-dose XTSJ group (90.74% ± 6.57%) (P < 0.05). However, the efficacy of XTSJ decoction was reduced in the CD44(-) groups; significant differences were only detected in the high-dose XTSJ group at 48 h (78.57% ± 6.94%) and 72 h (72.12% ± 7.68%) when compared with the other CD44- groups (P < 0.05). Notably, these differences were highly consistent with the Notch-1, Hes1, VEGF and Ki-67 expression in these cells. Similarly, in vivo, XTSJ decoction inhibited tumor growth in a dose-dependent manner. A significant difference was observed in the medium- (1.76 ± 0.15) and high-dose XTSJ (1.33 ± 0.081) groups compared with the GCSCs control group (2.72 ± 0.25) and the low-dose XTSJ group (2.51 ± 0.25) (P < 0.05). We also detected a remarkable decrease of MVD in the medium- (7.10 ± 0.60) and high-dose XTSJ (5.99 ± 0.47) groups compared with the GCSC control group (8.15 ± 0.42) and the low-dose XTSJ group (8.14 ± 0.46) (P < 0.05). Additionally, CD44 expression was decreased in these groups [medium- (4.43 ± 0.45) and high-dose XTSJ groups (3.56 ± 0.31) vs the GCSC control (5.96 ± 0.46) and low dose XTSJ groups (5.91 ± 0.38)] (P < 0.05). The significant differences in Notch-1, Hes1, VEGF and Ki-67 expression highly mirrored the results of XTSJ decoction in inhibiting tumor growth, MVD and CD44 expression.. Notch-1 may play an important role in regulating the proliferation of GCSCs; XTSJ decoction could attenuate tumor angiogenesis, at least partially, by inhibiting Notch-1.

Topics: Angiogenesis Inhibitors; Animals; Antineoplastic Agents, Phytogenic; Basic Helix-Loop-Helix Transcription Factors; Cell Line, Tumor; Cell Proliferation; Dose-Response Relationship, Drug; Drugs, Chinese Herbal; Gene Expression Regulation, Neoplastic; Homeodomain Proteins; Humans; Hyaluronan Receptors; Ki-67 Antigen; Male; Mice, Nude; Neoplastic Stem Cells; Neovascularization, Pathologic; Rats, Sprague-Dawley; Receptor, Notch1; Signal Transduction; Stomach Neoplasms; Time Factors; Transcription Factor HES-1; Vascular Endothelial Growth Factor A; Xenograft Model Antitumor Assays

Notch and Wnt signaling play critical roles in the regulation of development and diseases. Several studies have previously reported that Notch may be a therapeutic target in the treatment of various types of human cancer. In this study, we report that activation of Notch1 inhibits the proliferation of BGC-823 gastric cancer cells. However, the activation of the Wnt/β‑catenin signaling pathway promotes the growth of BGC-823 cells. Furthermore, the combinational activation of the two signaling pathways promotes the proliferation of BGC-823 cells. These data suggest that the activation of Wnt signaling overcomes the pro-apoptotic role of Notch in BGC-823 gastric cancer cells.

Topics: Apoptosis; Basic Helix-Loop-Helix Transcription Factors; Cell Cycle Checkpoints; Cell Line, Tumor; Cyclin E; Cyclin-Dependent Kinase 2; Doxycycline; Homeodomain Proteins; Humans; Lithium Chloride; Proto-Oncogene Proteins c-myc; Receptor, Notch1; Signal Transduction; Stomach Neoplasms; Transcription Factor HES-1; Wnt Proteins

Although JAK2 inhibitors can result in antitumor activity against various tumors, some tumors have showed insensitivity or resistance to the inhibitors. To investigate the possible mechanisms underlying responses of gastric cancer (GC) cells to AG490, a specific JAK2 inhibitor, human GC cell lines SGC7901 and AGS were used. AG490 did not significantly induce apoptosis in SGC7901 cells, but it did in AGS cells. Interestingly, in SGC7901 cells, AG490 led to increased nuclear translocation of total JAK2 proteins, accompanied with initial inactivation but later reactivation of JAK2. However, in AGS cells, AG490 led to decreased nuclear localization of total JAK2 proteins, accompanied with sustained inactivation of JAK2. Moreover, silencing of human homolog of Drosophila Hairy and enhancer of split (Hes) 1 with siRNA partly blocked AG490-induced nuclear translocation of JAK2, and enhanced AG490-induced apoptosis in SGC7901 cells. The results collectively suggested that nuclear JAK2 signaling pathway may act as an escape way from JAK2 inhibitors in some GC cells.

Topics: Antineoplastic Agents; Apoptosis; Basic Helix-Loop-Helix Transcription Factors; Blotting, Western; Cell Nucleus; Cell Proliferation; Cytoplasm; Fluorescent Antibody Technique; Homeodomain Proteins; Humans; Immunoenzyme Techniques; Immunoprecipitation; Janus Kinase 2; Phosphorylation; Protein Transport; RNA, Small Interfering; Signal Transduction; Stomach Neoplasms; Transcription Factor HES-1; Tumor Cells, Cultured; Tyrphostins

The biologic effects of Notch1 and Notch2 vary with cancer types and their potential role(s) in gastric cancers (GCs) remains largely unknown.. This study aimed to address the previously mentioned issue by checking the expression of Notch1, Notch2, and Notch target gene Hes1 in GCs, premalignant gastric lesions, and noncancerous endoscopic gastric mucosa and by inhibiting Notch signal transduction in GC cells.. The status of Notch1, Notch2, and Hes1 expression in 74 GC surgical specimens, 10 endoscopic samples, and 4 human GC cell lines was evaluated by tissue microarray-based immunohistochemical staining, Western blotting, and reverse transcription-polymerase chain reaction, and the importance of Notch signaling was elucidated by treating 2 GC cell lines with 2 γ-secretase inhibitors.. Notch1 was undetectable in noncancerous gastric mucosa but was expressed with nuclear translocation in 16.7% (4 of 24) of chronic gastritis, 50.0% (9 of 18) of intestinal metaplasia, 54.2% (26 of 48) of intestinal GC, and 23.1% (6 of 26) of diffuse GC, showing distinct differences of Notch1 detection rates between either intestinal metaplasia and chronic gastritis or intestinal GCs and diffuse GCs (P  =  .03; P  =  .005, respectively). Notch2 nuclear translocation frequencies were 10.0% (1 of 10) in noncancerous endoscopic mucosa, 71.4% (30 of 42) in premalignant lesions, and 97.3% (72 of 74) in GC tissues, demonstrating a correlation of Notch2 expression with both intestinal GC and diffuse GC formation (P < .001). The rates of nuclear-Hes1 labeling were 1 of 10 among noncancerous, 42.9% premalignant, and 81.1% cancer tissues, which were closely correlated with Notch2 (P < .001) rather than Notch1 (P  =  .42) nuclear translocation. Only Notch2 was expressed accompanied with Hes1 nuclear labeling in the 4 GC cell lines established from diffuse GC cases. Inhibition of Notch signaling with γ-secretase inhibitors, L-685,458 and DAPT, prevented Hes1 nuclear translocation but neither suppressed growth nor induced cell death.. This study demonstrated a close correlation of Notch2 expression with GC formation and the potential link of Notch1 upregulation with intestinal-like phenotypes of gastric lesions. Although inhibition of Notch activity failed to achieve anti-GC effects, the activated Notch signaling may reflect a potential GC risk.

Topics: Adenocarcinoma; Basic Helix-Loop-Helix Transcription Factors; Cell Line, Tumor; Gastrectomy; Gastric Mucosa; Gene Expression Regulation, Neoplastic; Homeodomain Proteins; Humans; Precancerous Conditions; Receptor, Notch1; Receptor, Notch2; RNA, Messenger; Signal Transduction; Stomach Neoplasms; Tissue Array Analysis; Transcription Factor HES-1