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 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*

As an important part of tumor microenvironment, neutrophils are poorly understood due to their spatiotemporal heterogeneity in tumorigenesis. Here we defined, at single-cell resolution, CD44-CXCR2- neutrophils as tumor-specific neutrophils (tsNeus) in both mouse and human gastric cancer (GC). We uncovered a Hippo regulon in neutrophils with unique YAP signature genes (e.g., ICAM1, CD14, EGR1) distinct from those identified in epithelial and/or cancer cells. Importantly, knockout of YAP/TAZ in neutrophils impaired their differentiation into CD54+ tsNeus and reduced their antitumor activity, leading to accelerated GC progression. Moreover, the relative amounts of CD54+ tsNeus were found to be negatively associated with GC progression and positively associated with patient survival. Interestingly, GC patients receiving neoadjuvant chemotherapy had increased numbers of CD54+ tsNeus. Furthermore, pharmacologically enhancing YAP activity selectively activated neutrophils to suppress refractory GC, with no significant inflammation-related side effects. Thus, our work characterized tumor-specific neutrophils in GC and revealed an essential role of YAP/TAZ-CD54 axis in tsNeus, opening a new possibility to develop neutrophil-based antitumor therapeutics.
Humans ; Animals ; Mice ; Adaptor Proteins, Signal Transducing/metabolism* ; Transcription Factors/metabolism* ; Stomach Neoplasms/pathology* ; Neutrophils/pathology* ; Signal Transduction/genetics* ; YAP-Signaling Proteins ; Tumor Microenvironment ; Hyaluronan Receptors/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 effects of long-chain noncoding RNA Linc00673 overexpression on proliferation and apoptosis of gastric cancer cells and its mechanisms. Methods: The recombinant lentivirus expressing plasmid pLVX-Linc00673 and the control empty plasmid pLVX-NC were packaged and amplified in 293T cells, and the recombinant lentivirus was transfected into gastric cancer cell line MGC-803 to establish a cell line stably overexpressing Linc00673. The expression of Linc00673 gene was detected by real-time fluorescence quantitative PCR. The growth and proliferation of cells were observed by MTT assay and clone formation assay. Cell cycle and apoptosis were detected by flow cytometry. The expressions of cell cycle related regulatory genes were detected by qPCR. The expressions of key molecules in the PI3K/Akt signaling pathway and tumor proliferation related proteins were detected by Western blot. Results: The expressions of Linc00673 in gastric cancer cell line MGC-803, BGC-823 and AGS were significantly higher than that in normal gastric mucosa cell line GES-1 (P＜0.05). MGC-803 cell line with stable overexpression of LINC00673 was established, and the expression level of LincC00673 was 200 times higher than that of the control empty carrier group. Overexpression of Linc00673 promoted proliferation of MGC-803 cells (P＜0.05) and clone formation (P＜0.05), inhibited cell apoptosis and affected the G1→S phase progression of cell cycle (P＜0.01). Overexpression of Linc00673 could affect the expressions of cell cycle regulatory gene CCNG2, P19 and CDK1 in MGC-803. Western blot showed that Linc00673 overexpression not only promoted the expressions of the key molecule pAkt in PI3K / Akt signaling pathway and its downstream target NF-κ B and Bcl-2 protein, but also up regulated the expressions of tumor related factors β-catenin and EZH2 proteins. Conclusion: Overexpression of Linc00673 may promote proliferation and inhibit apoptosis of MGC-803 cells through PI3K/Akt signaling pathway.
Apoptosis ; Cell Line, Tumor ; Cell Proliferation ; Humans ; Phosphatidylinositol 3-Kinases ; Proto-Oncogene Proteins c-akt/metabolism* ; RNA, Long Noncoding/genetics* ; Stomach Neoplasms/pathology*

YWHAE gene is located on chromosome 17p13.3, and its product 14-3-3epsilon protein belongs to 14-3-3 protein family. As a molecular scaffold, YWHAE participates in biological processes such as cell adhesion, cell cycle regulation, signal transduction and malignant transformation, and is closely related to many diseases. Overexpression of YWHAE in breast cancer can increase the ability of proliferation, migration and invasion of breast cancer cells. In gastric cancer, YWHAE acts as a negative regulator of MYC and CDC25B, which reduces their expression and inhibits the proliferation, migration, and invasion of gastric cancer cells, and enhances YWHAE-mediated transactivation of NF-κB through CagA. In colorectal cancer, YWHAE lncRNA, as a sponge molecule of miR-323a-3p and miR-532-5p, can compete for endogenous RNA through direct interaction with miR-323a-3p and miR-532-5p, thus up-regulating K-RAS/ERK/1/2 and PI3K-AKT signaling pathways and promoting the cell cycle progression of the colorectal cancer. YWHAE not only mediates tumorigenesis as a competitive endogenous RNA, but also affects gene expression through chromosome variation. For example, the FAM22B-YWHAE fusion gene caused by t(10; 17) (q22; p13) may be associated with the development of endometrial stromal sarcoma. At the same time, the fusion transcript of YWHAE and NUTM2B/E may also lead to the occurrence of endometrial stromal sarcoma. To understand the relationship between YWHAE, NUTM2A, and NUTM2B gene rearrangement/fusion and malignant tumor, YWHAE-FAM22 fusion gene/translocation and tumor, YWHAE gene polymorphism and mental illness, as well as the relationship between 17p13.3 region change and disease occurrence. It provides new idea and basis for understanding the effect of YWHAE gene molecular mechanism and genetic variation on the disease progression, and for the targeted for the diseases.
14-3-3 Proteins/metabolism* ; Breast Neoplasms/genetics* ; Cell Line, Tumor ; Cell Proliferation/genetics* ; Cell Transformation, Neoplastic/genetics* ; Colorectal Neoplasms/genetics* ; Endometrial Neoplasms ; Female ; Gene Expression Regulation, Neoplastic ; Humans ; MicroRNAs/genetics* ; Phosphatidylinositol 3-Kinases/metabolism* ; Sarcoma, Endometrial Stromal/pathology* ; Stomach Neoplasms/genetics* ; Transcription Factors/genetics* ; Translocation, Genetic

OBJECTIVE: To investigate the expression of circPCSK5 in gastric cancer (GC) and its role in regulation of the proliferation, invasion and epithelial-mesenchymal transition (EMT) of GC cells. METHODS: High-throughput sequencing was performed in 3 pairs of GC and adjacent gastric mucosa tissues to obtain the differential expression profile of circRNA. The expression of circPCSK5 was detected in 62 patients undergoing radical surgery for GC using RT-qPCR, and the correlation between circPCSK5 expression level and clinicopathological data of the patients was analyzed. The overall survival and disease-free survival of the patients were assessed with Kaplan-Meier survival analysis, and the independent risk factors affecting the patients' prognosis were analyzed using Cox proportional hazards regression model. The stability and subcellular localization of circPCSK5 were assessed using RNase R and actinomycin D assays, fluorescence in situ hybridization and nucleocytoplasmic separation assay. CCK-8 assay, EdU assay and Transwell assay were employed to examine the changes in proliferation, migration and invasion of GC cells with circPCSK5 knockdown or overexpression; Western blotting and RT-qPCR assays were used to detect the expression levels of EMT markers in the transfected cells. RESULTS: The expression of circPCSK5 was significantly upregulated in GC tissues and cells (P < 0.001, P < 0.01). The expression level of circPCSK5 was positively correlated with tumor size, vascular invasion, lymph node metastasis and AJCC stage of GC (P < 0.05). The overall survival and disease-free survival were significantly lower in GC patients with high circPCSK5 expression than in those with low circPCSK5 expression (P < 0.001). High circPCSK5 expression was an independent risk factor for a poor prognosis of GC patients (P < 0.05). Knockdown of circPCSK5 significantly inhibited the proliferation, migration and invasion of HGC27 cells (P < 0.01), increased the expressions of E-cadherin, and decreased the expression of N-cadherin and vimentin (P < 0.01). CircPCSK5 overexpression promoted the proliferation, migration and invasion of MKN45 cells (P < 0.01), reduced E-cadherin expression and increased N-cadherin and vimentin expressions (P < 0.01). CONCLUSION CircPCSK5 is highly expressed in GC and promotes the proliferation, invasion and EMT of GC cells, suggesting its potential as a prognostic biomarker and therapeutic target for GC.
Humans ; Epithelial-Mesenchymal Transition/genetics* ; Stomach Neoplasms/pathology* ; Vimentin/metabolism* ; Neoplasm Invasiveness/genetics* ; In Situ Hybridization, Fluorescence ; Cell Movement/genetics* ; Gene Expression Regulation, Neoplastic ; Cell Line, Tumor ; Cell Proliferation/genetics* ; Cadherins/metabolism*