BACKGROUND: The transcription factor POU2F1 regulates the expression levels of microRNAs in neoplasia. However, the miR-29b1/a cluster modulated by POU2F1 in gastric cancer (GC) remains unknown. METHODS: Gene expression in GC cells was evaluated using reverse-transcription polymerase chain reaction (PCR), western blotting, immunohistochemistry, and RNA in situ hybridization. Co-immunoprecipitation was performed to evaluate protein interactions. Transwell migration and invasion assays were performed to investigate the biological behavior of GC cells. MiR-29b1/a cluster promoter analysis and luciferase activity assay for the 3'-UTR study were performed in GC cells. In vivo tumor metastasis was evaluated in nude mice. RESULTS: POU2F1 is overexpressed in GC cell lines and binds to the miR-29b1/a cluster promoter. POU2F1 is upregulated, whereas mature miR-29b-3p and miR-29a-3p are downregulated in GC tissues. POU2F1 promotes GC metastasis by inhibiting miR-29b-3p or miR-29a-3p expression in vitro and in vivo . Furthermore, PIK3R1 and/or PIK3R3 are direct targets of miR-29b-3p and/or miR-29a-3p , and the ectopic expression of PIK3R1 or PIK3R3 reverses the suppressive effect of mature miR-29b-3p and/or miR-29a-3p on GC cell metastasis and invasion. Additionally, the interaction of PIK3R1 with PIK3R3 promotes migration and invasion, and miR-29b-3p , miR-29a-3p , PIK3R1 , and PIK3R3 regulate migration and invasion via the phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/Akt/mTOR) pathway in GC cells. In addition, POU2F1 , PIK3R1 , and PIK3R3 expression levels negatively correlated with miR-29b-3p and miR-29a-3p expression levels in GC tissue samples. CONCLUSIONS The POU2F1 - miR-29b-3p / miR-29a-3p-PIK3R1 / PIK3R1 signaling axis regulates tumor progression and may be a promising therapeutic target for GC.
MicroRNAs/metabolism* ; Humans ; Stomach Neoplasms/pathology* ; Cell Line, Tumor ; Cell Movement/physiology* ; Phosphatidylinositol 3-Kinases/metabolism* ; Animals ; Mice ; Octamer Transcription Factor-1/metabolism* ; Mice, Nude ; Class Ia Phosphatidylinositol 3-Kinase/metabolism* ; Neoplasm Invasiveness ; Gene Expression Regulation, Neoplastic/genetics* ; Male ; Immunohistochemistry ; Female

This study aims to investigate the pathogenesis of precancerous lesions of gastric cancer(PLGC) and explore the potential molecular mechanism of Weifuchun Capsules(WFC) in treating PLGC via the nuclear factor-κB(NF-κB)/NOD-like receptor protein 3(NLRP3) inflammasome signaling pathway. Ninety male SPF-grade Wistar rats were randomized into a normal feeding group and a modeling group. The normal feeding group received a regular diet, while the modeling group was subjected to the disease-syndrome combined modeling of PLGC. Specifically, the rats had free access to the water containing 120 μg·mL~(-1) N-methyl-N'-nitro-N-nitrosoguanidine(MNNG) and received a diet containing 0.05% ranitidine in an irregular feeding pattern(alternations between fasting and overfeeding). After 15 weeks, the rats in the normal feeding group were randomized into control, control-NF-κB activator betulinic acid(C-BA), and control-NF-κB inhibitor pyrrolidine dithiocarbamaten(C-PDTC) groups. Meanwhile, the rats in the modeling group continuously underwent the modeling procedure and were randomized into model, WFC, model-NF-κB activator(M-BA), and model-NF-κB inhibitor(M-PDTC) groups. The model group and control group were given aseptic water by intragastric administration, once a day. WFC was given at a dose(432 mg·kg~(-1)) 6 times the equivalent dose for adults(body weight: 60 kg) by gavage, once a day. The rats in the C-BA and M-BA groups were administrated with BA by intraperitoneal injection at a dose of 10 mg·kg~(-1), twice a week. The rats in the C-PDTC and M-PDTC groups were administrated with PDTC by intraperitoneal injection at a dose of 50 mg·kg~(-1), twice a week. The interventions were carried out for 4 weeks. Histopathological changes of the gastric mucosa were observed and scored by hematoxylin-eosin(HE) and alcian blue-periodic acid Sthiff(AB-PAS) staining. The levels of inflammatory cytokines including interleukin(IL)-1β, IL-6, IL-18, tumor necrosis factor-alpha(TNF-α), and IL-10 in the gastric tissue were determined by enzyme-linked immunosorbent assay(ELISA). The expression levels of proteins associated with the NF-κB/NLRP3 inflammasome in the gastric mucosa were determined by Western blot. The positive expression areas of proteins related to NF-κB/NLRP3 inflammasome in the gastric mucosa were measured by immunohistochemistry. The results showed that compared with the control group, the model, C-BA, and M-BA groups showed significantly risen scores of mucosal inflammation, degree of inflammatory activity, gland atrophy, and intestinal metaplasia, and the model and M-BA groups showed significanly risen scores of dysplasia. Compared with the model group, the WFC group demonstrated significantly declined scores of mucosal inflammation and degree of inflammatory activity, as well as declined scores of intestinal metaplasia and dysplasia. Compared with the control group, the model and C-BA groups showed significantly elevated levels of IL-1β, IL-6, IL-18, and TNF-α in the gastric tissue, and the model group showed significantly elevated level of IL-10. In addition, the model and C-BA groups showed significantly up-regulated expression of NF-κB p65, NLRP3, cysteine-aspartic acid protease 1(caspase-1), and apoptosis-associated speck-like protein containing a CARD(ASC) in the gastric mucosa and increased positive expression areas of NF-κB p65, NLRP3, and ASC. Compared with the model group, the WFC group showed significantly decreased levels of IL-1β, IL-6, IL-18, TNF-α, and IL-10 in the gastric tissue, and the M-PDTC group showed significantly lowered levels of IL-1β, IL-18, and TNF-α in the gastric mucosa. Both WFC and M-PDTC groups demonstrated significantly down-regulated expression levels of NF-κB p65, phosphorylated NF-κB p65(p-NF-κB p65), NLRP3, and caspase-1 in the gastric mucosa, along with significant decreases in the positive expression areas of NF-κB p65, NLRP3, and ASC. In conclusion, the pathogenesis of PLGC is closely related to the activation of the NF-κB/NLRP3 inflammasome signaling pathway. WFC can alleviate mucosal inflammation, inhibit glandular atrophy, partially reverse intestinal metaplasia, and reduce dysplasia to delay the process of inflammation-cancer transformation, and meanwhile it can effectively lower the levels of inflammatory cytokines and down-regulate the expression of pathway-related proteins in the stomach. Therefore, WFC may treat PLGC by inhibiting the NF-κB/NLRP3 inflammasome signaling pathway.
Animals ; Male ; NF-kappa B/genetics* ; Rats ; Rats, Wistar ; Drugs, Chinese Herbal/administration & dosage* ; Signal Transduction/drug effects* ; NLR Family, Pyrin Domain-Containing 3 Protein/metabolism* ; Stomach Neoplasms/pathology* ; Inflammasomes/genetics* ; Humans ; Precancerous Conditions/metabolism* ; Capsules

OBJECTIVES: To investigate the mechanism through which salidroside inhibits proliferation of gastric cancer (GC) cells focusing on glucose metabolic reprogramming pathways. METHODS: High-throughput sequencing combined with bioinformatics analysis was employed to identify the potential targets of salidroside in human GC MGC-803 cells. Liposome-mediated transfection experiments were carried out to validate the functional and mechanistic roles of these targets. CCK-8 and colony formation assays were used to assess the effects of salidroside on GC cell viability and clonogenic ability. qRT-PCR, Western blotting, and biochemical assay kits were used to analyze the regulatory effects of salidroside on the miR-1343-3p-OGDHL/PDHB enzyme complex-pyruvate metabolic pathway in GC cells. RESULTS: Bioinformatics analysis suggested that the tumor-suppressive factor miR-1343-3p negatively regulated the key glycolytic enzyme gene oxoglutarate dehydrogenase-like (OGDHL) in GC cells, and OGDHL and pyruvate dehydrogenase E1 subunit beta (PDHB) were both significantly upregulated in GC tissues, which was close by correlated with reduced survival rates of GC patients. In MGC-803 cells, salidroside treatment significantly enhanced the expression level of miR-1343-3p and downregulated OGDHL expression, resulting in disruption of the stability of PDHB, reduced pyruvate oxidative decarboxylation, and consequently decreased production of acetyl-CoA and ATP. CONCLUSIONS Salidroside inhibits GC cell proliferation possibly by regulating the miR-1343-3p-OGDHL/PDHB enzyme complex-pyruvate metabolic pathway, which provides new insights into its anti-tumor mechanisms and suggests new strategies for targeted therapy for GC.
Humans ; Stomach Neoplasms/pathology* ; MicroRNAs/genetics* ; Cell Proliferation/drug effects* ; Glucosides/pharmacology* ; Phenols/pharmacology* ; Cell Line, Tumor ; Glucose/metabolism* ; Pyruvate Dehydrogenase (Lipoamide)/metabolism*

OBJECTIVES: Gastric cancer is a common cancer of the digestive system. Long non-coding RNA (lncRNA) plays an important role in the formation and development of gastric cancer. This study aims to investigate the effect of long non-coding lncRNA 114227 on biologic behaviors in gastric cancer cells. METHODS: The experiment was divided into 4 groups: a negative control (NC) group, a lncRNA 114227 small interference (si-lncRNA 114227) group, an empty vector (Vector) group, and an overexpression vector (OE-lncRNA 114227) group. The expressions of lncRNA 114227 in gastric mucosa and gastric cancer tissues, gastric mucosal epithelial cells and different gastric cancer strains were determined by real-time reverse transcription PCR (real-time RT-PCR).The proliferation were detected by CCK-8 assay in gastric cancer cells. The epithelial-mesenchymal transformation (EMT) was utilized by Transwell assay, scratch healing assay, and Western blotting in gastric cancer cells. The effect of lncRNA 114227 on proliferation of gastric cancer cells was detected by tumor bearing experiment in nude mice in vivo. RESULTS: The expression level of lncRNA 114227 in the gastric cancer tissues was significantly lower than that in the gastric mucosa tissues, and in 4 kinds of gastric cancer strains was all significantly lower than that in gastric mucosal epithelial cells (all P<0.01). In vitro, the proliferation and migration abilities of gastric cells were significantly reduced after overexpressing lncRNA 114227, and cell proliferation and migration were enhanced after silencing lncRNA 114227 (all P<0.05). The results of in vivo subcutaneous tumorigenesis in nude mice showed that the tumorigenic volume of the tumor-bearing mice in the OE-lncRNA 114227 group was significantly smaller than that of the Vector group, and the tumorigenic quality was lower than that of the Vector group (P<0.05), indicating that lncRNA 114227 inhibited tumorigenesis. CONCLUSIONS The expression of lncRNA 114227 is downregulated in gastric cancer gastric cancer tissues and cell lines. LncRNA 114227 may inhibit the proliferation and migration of gastric cancer cells through EMT process.
Animals ; Mice ; RNA, Long Noncoding/metabolism* ; Stomach Neoplasms/pathology* ; Mice, Nude ; Cell Line, Tumor ; Cell Proliferation/genetics* ; Carcinogenesis/genetics* ; Cell Movement/genetics* ; Epithelial-Mesenchymal Transition/genetics* ; Gene Expression Regulation, Neoplastic ; Apoptosis/genetics*

Objective: To analyze the clinicopathological features and gene mutations of primary gastrointestinal stromal tumors (GISTs) of the stomach and intestine and the prognosis of intermediate- and high-risk GISTs. Methods: This was a retrospective cohort study. Data of patients with GISTs admitted to Tianjin Medical University Cancer Institute and Hospital from January 2011 to December 2019 were collected retrospectively. Patients with primary gastric or intestinal disease who had undergone endoscopic or surgical resection of the primary lesion and were confirmed pathologically as GIST were included. Patients treated with targeted therapy preoperatively were excluded. The above criteria were met by 1061 patients with primary GISTs, 794 of whom had gastric GISTs and 267 intestinal GISTs. Genetic testing had been performed in 360 of these patients since implementation of Sanger sequencing in our hospital in October 2014. Gene mutations in KIT exons 9, 11, 13, and 17 and PDGFRA exons 12 and 18 were detected by Sanger sequencing. The factors investigated in this study included: (1) clinicopathological data, such as sex, age, primary tumor location, maximum tumor diameter, histological type, mitotic index (/5 mm²), and risk classification; (2) gene mutation; (3) follow-up, survival, and postoperative treatment; and (4) prognostic factors of progression-free survival (PFS) and overall survival (OS) for intermediate- and high-risk GIST. Results: (1) Clinicopathological features: The median ages of patients with primary gastric and intestinal GIST were 61 (8-85) years and 60 (26-80) years, respectively; The median maximum tumor diameters were 4.0 (0.3-32.0) cm and 6.0 (0.3-35.0) cm, respectively; The median mitotic indexes were 3 (0-113)/5 mm² and 3 (0-50)/5 mm², respectively; The median Ki-67 proliferation indexes were 5% (1%-80%) and 5% (1%-50%), respectively. The rates of positivity for CD117, DOG-1, and CD34 were 99.7% (792/794), 99.9% (731/732), 95.6% (753/788), and 100.0% (267/267), 100.0% (238/238), 61.5% (163/265), respectively. There were higher proportions of male patients (χ²=6.390, P=0.011), tumors of maximum diameter > 5.0 cm (χ²=33.593, P<0.001), high-risk (χ²=94.957, P<0.001), and CD34-negativity (χ²=203.138, P<0.001) among patients with intestinal GISTs than among those with gastric GISTs. (2) Gene mutations: Gene mutations were investigated in 286/360 patients (79.4%) with primary gastric GISTs and 74/360 (20.6%) with primary intestinal GISTs. Among the 286 patients with gastric primary GISTs, 79.4% (227/286), 8.4% (24/286), and 12.2% (35/286), had KIT mutations, PDGFRA mutations, and wild-type, respectively. Among the 74 patients with primary intestinal GISTs, 85.1% (63/74) had KIT mutations and 14.9% (11/74) were wild-type. The PDGFRA mutation rate was lower in patients with intestinal GISTs than in those with gastric GISTs[ 0% vs. 8.4%(24/286), χ²=6.770, P=0.034], whereas KIT exon 9 mutations occurred more often in those with intestinal GISTs [22.2% (14/63) vs. 1.8% (4/227), P<0.001]. There were no significant differences between gastric and intestinal GISTs in the rates of KIT exon 11 mutation type and KIT exon 11 deletion mutation type (both P>0.05). (3) Follow-up, survival, and postoperative treatment: After excluding 228 patients with synchronous and metachronous other malignant tumors, the remaining 833 patients were followed up for 6-124 (median 53) months with a follow-up rate of 88.6% (738/833). None of the patients with very low or low-risk gastric (n=239) or intestinal GISTs (n=56) had received targeted therapy postoperatively. Among 179 patients with moderate-risk GISTs, postoperative targeted therapy had been administered to 88/155 with gastric and 11/24 with intestinal GISTs. Among 264 patients with high-risk GISTs, postoperative targeted therapy had been administered to 106/153 with gastric and 62/111 with intestinal GISTs. The 3-, 5-, and 10-year PFS of patients with gastric or intestinal GISTs were 96.5%, 93.8%, and 87.6% and 85.7%, 80.1% and 63.3%, respectively (P<0.001). The 3-, 5-, and 10-year OS were 99.2%, 98.8%, 97.5% and 94.8%, 92.1%, 85.0%, respectively (P<0.001). (4) Analysis of predictors of intermediate- and high-risk GISTs: The 5-year PFS of patients with gastric and intestinal GISTs were 89.5% and 73.2%, respectively (P<0.001); The 5-year OS were 97.9% and 89.3%, respectively (P<0.001). Multivariate analysis showed that high risk (HR=2.918, 95%CI: 1.076-7.911, P=0.035) and Ki-67 proliferation index > 5% (HR=2.778, 95%CI: 1.389-5.558, P=0.004) were independent risk factors for PFS in patients with intermediate- and high-risk GISTs (both P<0.05). Intestinal GISTs (HR=3.485, 95%CI: 1.407-8.634, P=0.007) and high risk (HR=3.753,95%CI:1.079-13.056, P=0.038) were independent risk factors for OS in patients with intermediate- and high-risk GISTs (both P<0.05). Postoperative targeted therapy was independent protective factor for PFS and OS (HR=0.103, 95%CI: 0.049-0.213, P<0.001; HR=0.210, 95%CI:0.078-0.564,P=0.002). Conclusions: Primary intestinal GIST behaves more aggressively than gastric GISTs and more frequently progress after surgery. Moreover, CD34 negativity and KIT exon 9 mutations occur more frequently in patients with intestinal GISTs than in those with gastric GISTs.
Male ; Humans ; Gastrointestinal Stromal Tumors/surgery* ; Retrospective Studies ; Ki-67 Antigen ; Stomach Neoplasms/pathology* ; Prognosis ; Mutation ; Intestines/pathology* ; Proto-Oncogene Proteins c-kit/genetics* ; Receptor, Platelet-Derived Growth Factor alpha/genetics*

Peritoneal metastasis of gastric cancer serving as the most frequent form of metastasis, is one of the leading causes of death. A portion of surgically treated patients often suffer from small peritoneal residual metastasis, which will lead to recurrence and metastasis of gastric cancer patients after surgery. Given these, the prevention and treatment of peritoneal metastasis of gastric cancer deserves more attention. Molecular residual disease (MRD) refers to the molecular abnormalities of tumor origin that cannot be found by traditional imaging or other laboratory methods after treatment, but can be found by liquid biopsy, representing the possibility of tumor persistence or clinical progress. In recent years, the detection of MRD based on ctDNA has gradually become a research hotspot in the prevention and treatment of peritoneal metastasis. Our team established a new method for MRD molecular diagnosis of gastric cancer, and reviewed the research achievements in this field.
Humans ; Stomach Neoplasms/pathology* ; Peritoneal Neoplasms/secondary* ; Liquid Biopsy ; Neoplasm, Residual/genetics*

OBJECTIVE: To investigate the expression of microRNA miR-431-5p in gastric cancer (GC) tissues and its effects on apoptosis and mitochondrial function in GC cells. METHODS: The expression level of miR-431-5p in 50 clinical samples of GC tissues and paired adjacent tissues was detected using real-time fluorescence quantitative PCR, and its correlation with the clinicopathological features of the patients was analyzed. A cultured human GC cell line (MKN-45 cells) were transfected with a miR-431-5p mimic or a negative control sequence, and the cell proliferation, apoptosis, mitochondrial number, mitochondrial potential, mitochondrial permeability transition pore (mPTP), reactive oxygen species (ROS) production and adenosine triphosphate (ATP) content were detected using CCK-8 assay, flow cytometry, fluorescent probe label, or ATP detection kit. The changes in the expression levels of the apoptotic proteins in the cells were detected with Western blotting. RESULTS: The expression level of miR-431-5p was significantly lower in GC tissues than in the adjacent tissues (P < 0.001) and was significantly correlated with tumor differentiation (P=0.0227), T stage (P=0.0184), N stage (P=0.0005), TNM stage (P=0.0414) and vascular invasion (P=0.0107). In MKN-45 cells, overexpression of miR-431-5p obviously inhibited cell proliferation and induced cell apoptosis, causing also mitochondrial function impairment as shown by reduced mitochondrial number, lowered mitochondrial potential, increased mPTP opening, increased ROS production and reduced ATP content. Overexpression of miR-431-5p significantly downregulated the expression of Bcl-2 and increased the expressions of pro-apoptotic proteins p53, Bcl-2 and cleaved caspase-3 protein. CONCLUSION The expression of miR-431-5p is down-regulated in GC, which results in mitochondrial function impairment and promotes cell apoptosis by activating the Bax/Bcl-2/caspase3 signaling pathway, suggesting the potential role of miR-431-5p in targeted therapy for GC.
Humans ; Apoptosis/genetics* ; bcl-2-Associated X Protein ; Caspase 3 ; Cell Line, Tumor ; Cell Proliferation/genetics* ; MicroRNAs/metabolism* ; Mitochondria/metabolism* ; Mitochondrial Permeability Transition Pore ; Reactive Oxygen Species ; Stomach Neoplasms/pathology*

OBJECTIVE: To investigate the expression of four-jointed box kinase 1 (FJX1) in gastric cancer (GC), its correlation with survival outcomes of the patients, and its role in GC progression. METHODS: The expression level of FJX1 in GC tissues and normal gastric mucosal tissues and its correlation with the survival outcomes of GC patients were analyzed using TCGA and GEO database GC cohort. Immunohistochemistry was used to detect FJX1 expression level in clinical specimens of GC tissue, and its correlations with the patients' clinicopathological parameters and prognosis were analyzed. Bioinformatic analysis was performed to identify the potential pathways of FJX1 in GC. The effects of FJX1 overexpression or FJX1 silencing on GC cell proliferation and expressions of proliferation-related proteins, PI3K, AKT, p-PI3K, and p-AKT were evaluated using CCK-8 assay and Western blotting. The effect of FJX1 overexpression on GC cell tumorigenicity was evaluated in nude mice. RESULTS: GC tissues showed significantly higher expressions of FJX1 mRNA and protein compared with normal gastric mucosa tissues (P < 0.05). The high expression of FJX1 was associated with poor prognosis of GC patients (P < 0.05) and served as an independent risk factor for poor survival outcomes in GC (P < 0.05). FJX1 was expressed mainly in the cytoplasm of GC cells in positive correlation with Ki67 expression (R=0.34, P < 0.05), and was correlated with CA199 levels, depth of tumor infiltration and lymph node metastasis of GC (P < 0.05). In the cell experiment, FJX1 level was shown to regulate the expressions of Ki67 and PCNA and GC cell proliferation (P < 0.05). Gene set enrichment analysis indicated that the PI3K/AKT pathway potentially mediated the effect of FJX1, which regulated the expressions of PI3K and AKT and their phosphorylated proteins. In nude mice, FJX1 overexpression in GC cells significantly promoted the growth of the transplanted tumors (P < 0.05). CONCLUSION FJX1 is highly expressed in GC tissues and is correlated with poor prognosis of GC patients. FJX1 overexpression promotes GC cell proliferation through the PI3K/AKT signaling pathway, and may serve as a potential prognostic biomarker and therapeutic target for GC.
Animals ; Mice ; Cell Proliferation ; Ki-67 Antigen ; Mice, Nude ; Phosphatidylinositol 3-Kinases ; Proto-Oncogene Proteins c-akt ; Signal Transduction ; Stomach Neoplasms/pathology* ; Humans ; Intercellular Signaling Peptides and Proteins/genetics*

Objective To clarify whether Helicobacter pylori (H. pylori) can promote metastasis of gastric cancer cells via the high-expression of induced B cell specific Moloney murine leukemia virus integration site 1 (Bmi-1). Methods The gastric cancer tissue specimens from 82 patients were collected for this study. The protein and gene expression level of Bmi-1 in gastric adenocarcinoma tissue were detected by immunohistochemistry and real time quantitative PCR, respectively. And meanwhile the correlation between Bmi-1 levels and pathological features, and prognosis of gastric cancer were analyzed retrospectively. Then, the GES-1 cells were transfected with pLPCX-Bmi-1 plasmid and infected with H. pylori respectively. After the Bmi-1 overexpression in GES-1 cells, the invasion ability of the GES-1 cells was detected by Transwell assay, and the cell cycle and apoptosis were detected by flow cytometry. Results The mRNA and protein of Bmi-1 expression in gastric cancer tissues were higher than tumor-adjacent tissue, and the high expression of Bmi-1 was positively correlated with tumor invasion, TNM stage, tumor differentiation, lymph node metastasis and H. pylori infection. When expression of Bmi-1 was up-regulated as a result of H.pylori infection or pLPCX-Bmi-1 transfection, the GES-1 cells had higher invasiveness and lower apoptosis rate with the above treatment respectively. Conclusion H. pylori infection can inhibit the apoptosis of gastric cancer cells and promote their invasion via up-regulating expression of Bmi-1.
Humans ; Cell Line, Tumor ; Helicobacter Infections/genetics* ; Helicobacter pylori ; Lymphatic Metastasis ; Retrospective Studies ; Stomach Neoplasms/pathology* ; Polycomb Repressive Complex 1/genetics*

Objective To investigate the effects of microRNA497 (miR-497) on the metastasis of gastric cancer and its possible molecular mechanism. Methods SGC-7901 gastric cancer parent cells were cultured in an ultra-low adhesion environment, and the anoikis resistance model of SGC-7901 cells was created after re-adhesion. Clone formation assay, flow cytometry, Transwell^TM test and scratch healing test were used to detect the differences of biological behavior compared with their parent cells. Fluorescence quantitative PCR was performed to detect the expression of miR-497. Western blot analysis was used to detect the changes of key proteins of Wnt/β-catenin signaling pathway and epithelial mesenchymal transformation (EMT) related proteins such as vimentin and E-cadherin. Parent cells and anoikis resistant SGC-7901 cells were transfected with miR-497 inhibitor or miR-497 mimic, and CCK-8 assay was used to detect the proliferation activity. Transwell^TM invasion assay was performed to detect the invasion ability of cells. Transwell^TM migration test and scratch healing assay was used to determine the migration ability. Western blot analysis was used to detect the expressions of Wnt1, β-catenin, vimentin and E-cadherin. By transfecting miR-497 mimic into the anoikis resistance SGC-7901 cells and inoculating them subcutaneously in nude mice, the changes in the volume and mass of tumor tissues were measured and recorded. Western blot analysis was used to determine the expressions of Wnt1, β-catenin, vimentin and E-cadherin of tumor tissues. Results Compared with the parent cells, the anoikis resistance SGC-7901 gastric cancer cells had faster proliferation rate, stronger colony formation, lower apoptosis rate, stronger invasion and migration ability. The expression of miR-497 was significantly decreased. After down-regulation of miR-497, the proliferation ability, invasion and migration ability were significantly enhanced. The expressions of Wnt1, β-catenin and vimentin increased significantly, while E-cadherin decreased notably. The results of up-regulation miR-497 were the opposite. The tumor growth rate, tumor volume and mass of miR-497 overexpression group were significantly lower than those of control group. The expressions of Wnt1, β-catenin and vimentin decreased significantly, while the expression of E-cadherin increased significantly. Conclusion The expression of miR-497 is low in the anoikis resistance SGC-7901 cells. miR-497 can inhibit the growth and metastasis of gastric cancer cells by blocking Wnt/β-catenin signaling pathway and EMT.
Animals ; Mice ; Humans ; beta Catenin/metabolism* ; MicroRNAs/metabolism* ; Vimentin/metabolism* ; Stomach Neoplasms/pathology* ; Anoikis/genetics* ; Wnt Signaling Pathway/genetics* ; Mice, Nude ; Cell Proliferation/genetics* ; Cadherins/genetics* ; Cell Line, Tumor ; Epithelial-Mesenchymal Transition/genetics* ; Cell Movement/genetics*