Invasion Of Gastric Adenocarcinoma Cells Research Articles

Downregulation of lncRNA PMS2L2 in patients with gastric adenocarcinoma predicts poor prognosis.

Long non-coding RNA PMS1 homolog 2 mismatch repair system component pseudogene 2 (PMS2L2) is a key player in lipopolysaccharide-induced inflammatory responses. Preliminary deep sequencing data revealed that PMS2L2 was downregulated in gastric adenocarcinoma (GA) tissues compared with healthy adjacent tissues and the aim of the present study was to investigate the role of PMS2L2 in GA. In the present study, reverse transcription-quantitative PCR assays were performed to analyze gene expression. Cell transfections were performed to analyze gene interactions and Transwell assays were performed to analyze cell invasion and migration. The results revealed that PMS2L2 expression was downregulated in cancer tissues obtained from patients with GA compared with healthy adjacent tissues and was not significantly affected by clinical stage. Furthermore, low levels of PMS2L2 in cancer tissues were closely associated with a low overall 5-year survival rate in patients. MicroRNA (miR)-25 was upregulated in GA tissues compared with healthy adjacent tissues and inversely associated with PMS2L2 levels. In GA cells in vitro, overexpression of PMS2L2 downregulated the expression of miR-25, while miR-25 overexpression did not significantly affect PMS2L2 expression. Furthermore, PMS2L2 overexpression inhibited the migration and invasion of GA cells. miR-25 overexpression partially rescued the decreased migration and invasion of GA cells caused by PMS2L2 overexpression. Therefore, PMS2L2 may downregulate miR-25 expression to inhibit GA.

HAVCR1 Affects the MEK/ERK Pathway in Gastric Adenocarcinomas and Influences Tumor Progression and Patient Outcome

The hepatitis A virus cellular receptor 1 (HAVCR1) gene as a sensitive and specific biomarker has been reported in various diseases. Especially, HAVCR1 overexpression promotes the development and progression of several human cancers. Hence, we aimed to detect the effects of HAVCR1 on gastric adenocarcinoma (GAC). We first determined the expression of HAVCR1 in GAC tissues compared with normal gastric tissues based on the Cancer Genome Atlas (TCGA) database using bioinformatics analysis methods. Then, we assessed the biological function of HAVCR1 in GAC cells using quantitative real-time reverse transcription-PCR (qRT-PCR), western blot, cell counting kit-8- (CCK-) 8, colony formation assay, wound healing assay, and transwell assay. Our results showed that HAVCR1 expression was upregulated in GAC tissues and positively associated with poor survival. Loss-of-function analyses indicated that knockdown of HAVCR1 inhibited the proliferation, colony formation, migration, and invasion of GAC cells. Furthermore, reduction of HAVCR1 in GAC cells can decrease the expression of phosphorylated MEK/ERK. These findings suggested that HAVCR1 may represent a potential biomarker for GAC prognosis, as well as a novel therapeutic target for GAC treatment.

Expression of miR-124 in gastric adenocarcinoma and the effect on proliferation and invasion of gastric adenocarcinoma SCG-7901 cells.

Expression of miR-124 in gastric adenocarcinoma cell line SGC-7901 and its effect on biological functions was investigated. Expression of miR-124 in cancer tissues and paracancerous tissues of gastric adenocarcinoma patients was detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). RT-qPCR was used to detect the expression of miR-124 in human normal gastric epithelial cells GES-1 and gastric adenocarcinoma SGC-7901 cells. Cells in miR-124 group were transfected with miR-124 agomir, cells in NC group were transfected with agomir-negative control sequence and cells in the control group were not transfected. MTT assay was used to detect cell proliferation, and Transwell invasion assay to detect cell invasion ability, and the effect of transfected miR-124 agonist on the proliferation and invasive ability of gastric adenocarcinoma cells was evaluated. RT-qPCR results showed that miR-124 expression was significantly downregulated in gastric adenocarcinoma tumor tissues compared with paracancerous tissues. Compared with cells of normal human gastric epithelial cell line GES-1, the expression of miR-124 human gastric adenocarcinoma SGC-7901 cells was significantly downregulated. At 12 h, there was no significant difference in OD at 490 nm in the three groups (P>0.05). OD (490) in the three groups showed a gradual upward trend. After transfection, proliferation curves of the three groups showed an upward trend, proliferation rate of miR-124 group was significantly lower than that of NC and control groups (P<0.05). The number of invading cells in miR-124 group was significantly lower than that in NC group and control group, but there was no significant difference in the number of cell invasion between the NC and control groups. miR-124 can inhibit the proliferation and invasion of gastric adenocarcinoma cells. Downregulation of miR-124 expression in gastric adenocarcinoma may be closely related to the development of gastric adenocarcinoma.

Reduced Expression of Deubiquitinase USP33 Is Associated with Tumor Progression and Poor Prognosis of Gastric Adenocarcinoma.

BackgroundUbiquitin-specific peptidase 33 (USP33) is a deubiquitinase that balances the ubiquitin status of proteins. It has been reported to act as a tumor suppressor in colorectal cancer and lung cancer. However, the expression pattern and clinical significance of USP33 have not been investigated in gastric adenocarcinoma (GAC).Material/MethodsWe explored the USP33 protein and RNA levels by immunohistochemistry (IHC), Western blot analysis, and qRT-PCR. The Pearson chi-square test was performed to evaluate the statistical associations between USP33 level and patient characteristics. Additionally, the relationship between USP33 expression and patient survival was investigated. Cellular studies, including proliferation assay, migration assay, and invasion assay, were conducted to demonstrate the underlying mechanisms of USP33 in GAC progression.ResultsThis study included 121 patients with GAC. USP33 showed a decreased expression in GAC tissues compared to adjacent normal gastric tissues. Low expression of USP33 was correlated with invasion depth and advanced TNM stage. According to survival analysis, upper location of tumor (P=0.003), invasion depth (P=0.048), advanced TNM stage (P=0.001), and low USP33 level (P=0.001) were all associated with poor overall survival of GAC patients. Cox analysis confirmed the independent role of USP33 in predicting patient survival. Cell experiments showed that USP33 overexpression significantly inhibited the proliferation, migration, and invasion of GAC cells.ConclusionsUSP33 was downregulated in GAC, and was an independent prognostic factor. In vitro results demonstrated the role of USP33 in suppressing tumor progression, suggesting that the developing an agonist of USP33 may be a novel direction for chemotherapy development.

Expression of ribophorine II is a promising prognostic factor in human gastric adenocarcinoma.

The increased invasiveness of gastric adenocarcinoma is important for progression and metastasis. In recent molecular biological studies, ribophorine II (RPN2) induced epithelial-mesenchymal transition and metastatic activity. However, no studies have evaluated the relationship between RPN2 expression, ability of cancer to invade/metastasis, and patient prognosis in gastric adenocarcinoma. Therefore, we have examined these factors. Immunohistochemical staining was performed to detect RPN2 and p53 in the primary lesion and adjacent normal gastric mucosa of 242 gastric adenocarcinoma patients who underwent resection surgery. We conducted clinicopathologic examinations and analyzed patient prognoses with the Kaplan-Meier method. Further, multivariate analysis was conducted using a Cox hazard model. Also, we analyzed the ability of invasion under inhibited RPN2 expression in vitro. RPN2 expression was observed in 119 of 242 cases of gastric adenocarcinoma patients. RPN2 expression was associated with a higher incidence of depth of wall invasion, lymph node metastasis, lymphatic invasion, venous invasion, peritoneal dissemination, histopathological stage, and p53 expression. In stageII and III curative resection cases, where recurrence is the most serious problem, cases that expressed RPN2 had a significantly lower 5-year survival rate and higher recurrence rate compared to the cases with no RPN2 expression. In the multivariate analysis for prognosis, RPN2 expression was found to be an independent factor. Also, gastric adenocarcinoma cell, had mutant-type p53, reduced the ability of invasion by knockout of RPN2 expression invitro. RPN2 expression correlates with gastric adenocarcinoma cell invasion and shows promise as a new prognostic factor in human gastric adenocarcinoma.

Cyclooxygenase-2 inhibition as a strategy for treating gastric adenocarcinoma

Cyclooxygenase-2 (COX-2) has been proven to play critical roles in inflammation as well as in cancer. Some studies have shown that the anti-inflammatory, immunosuppressive and anti-arthritic effects of celecoxib are mainly attributed to the inhibition of COX-2 expression. The present study aimed to investigate the function of COX-2 in human gastric adenocarcinoma (GAC). Forty-five cases of human GAC tissues and corresponding adjacent non-cancerous tissues (ANCTs) were collected. The expression of COX-2 and proliferating cell nuclear antigen (PCNA) was assessed using immunohistochemical assay through a tissue microarray procedure. GAC cells (SGC-7901 and MKN-45) invitro were treated with COX-2 siRNA or different concentrations of celecoxib to observe their effects on cell proliferation, invasion and the underlying molecular mechanisms. As a consequence, the expression of COX-2 and PCNA was found in cancer tissues with a higher strong reactivity rate, compared with the ANCTs (80.0 vs. 53.3%, P=0.011; 68.9 vs. 48.9%, P=0.047), and COX-2 was positively associated with lymph node metastasis of GAC patients (P=0.011). Targeted knockdown of COX-2 inhibited the proliferation, migration and invasion of GAC cells with decreased expression of PCNA. COX-2 inhibitor celecoxib also suppressed the proliferative activities of GAC cells with decreased expression of COX-2 and PCNA. In addition, the tumor volume in the MKN-45 subcutaneous tumor model treated with siCOX-2 was significantly smaller than that of the negative control (NC) group (P<0.01). Taken together, our findings offer a strong preclinical rationale to target COX-2 signaling as a therapeutic strategy to improve the treatment of gastric adenocarcinoma.

Additive effects of EGF and IL-1β regulate tumor cell migration and invasion in gastric adenocarcinoma via activation of ERK1/2

Growth and inflammatory factors are associated with poor prognosis in gastric adenocarcinoma (GA); however, the additive effects of growth and inflammatory factors in GA remain unclear. In this study, we investigated the ability of epidermal growth factor (EGF) and interleukin (IL-1β) to activate extracellular signal-regulated kinase (ERK)1/2 in GA cells, and correlated the relationships between their roles with the metastatic potential both in GA cells and GA tissues. The effects of EGF, IL-1β and EGF plus IL-1β in AGS and MKN-45 GA cells were examined using western blotting, Transwell migration and invasion assays, immunocytochemical staining and an activator protein (AP)-1 luciferase reporter gene assay, and was further characterized in GA tissues by immunohistochemistry. The results exhibited that EGF and IL-1β additively activated ERK1/2, increased migration and invasion than either EGF or IL-1β alone in AGS and MKN-45 cells. The mechanisms were involved in upregulating MMP-9 expression through increasing AP-1 transcriptional activity via ERK1/2 pathway; these effects were dose-dependently inhibited by silencing ERK1/2 or using U0126. In vivo data also confirmed that the overexpression of p-ERK1/2 in GA tissues correlated well with the EGF, IL-1β, EGF plus IL-1β, and was associated with metastasis, which was well correlation with the expression of MMP-9 and c-fos (AP-1). The results demonstrate that growth and inflammatory factors play an important role in metastasis of GA by additively activating ERK-1/2 and AP-1, and upregulating MMP-9. As both cytokines contribute to the migration and invasion of GA cells, EGF/IL-1β/ERK1/2 pathways may be key pathways closely associated with GA progression.

Knockdown of HMGB1 inhibits growth and invasion of gastric cancer cells through the NF-κB pathway in vitro and in vivo

High mobility group box 1 (HMGB1) as a novel inflammatory molecule has been shown to be involved in a variety of cell physiological and pathological behaviors including immune response, inflammation and cancer. Evidence suggests that HMGB1 plays a critical role in the development and progression of multiple malignancies. However, the underlying molecular mechanisms for the HMGB1-mediated growth and invasion of gastric cancer have not yet been elucidated. The present study investigated the expression of HMGB1 in gastric adenocarcinoma (GAC) and the mechanisms by which it contributes to tumor growth and invasion. The correlation between HMGB1 expression and clinicopathological characteristics of GAC patients was assessed by immunohistochemical assay through tissue microarray procedures. The RNA and protein expressions of HMGB1 and downstream factors were detected by quantitative PCR and western blot assays; cell proliferation and invasion were determined by MTT, wound-healing and 3D-Matregel assays, subcutaneous SGC-7901 tumor models were established to verify tumor growth in vivo. We demonstrated that, the expression of HMGB1 was significantly increased in the nucleus of GAC tissues compared with that in adjacent non-cancer tissues (88.6 vs.70.5%, P<0.001), and correlated with the metastatic lymph node of GAC (P=0.018). Furthermore, knockdown of HMGB1 by shRNA inhibited cell proliferative activities and invasive potential, and downregulated the expression of NF-κB p65, PCNA and MMP-9 in GAC cells (SGC-7901 and AGS). The tumor volumes in SGC7901 subcutaneous nude mouse models treated with Lv-shHMGB1 was significantly smaller than those of the nonsense sequence group. Taken together, these findings suggest that increased expression of HMGB1 is associated with tumor metastasis of GAC, and knockdown of HMGB1 suppresses growth and invasion of GAC cells through the NF-κB pathway invitro and in vivo, suggesting that HMGB1 may serve as a potential therapeutic target for GAC.

Knockdown of MMP11 Inhibits Proliferation and Invasion of Gastric Cancer Cells

Matrix metalloproteinase 11 (MMP11 or stromelysin-3) has recently been reported to play a crucial role in the development and progression of multiple malignancies. The aim of this study was to investigate the function of MMP11 expression in human gastric adenocarcinoma (GAC). Using immunohistochemistry assay, we studied the expression level of MMP11 in GAC and adjacent non-cancerous tissues (ANCT). The association between MMP11 expression and tumor size and pathological grade, as well as metastatic potential was analyzed. Through small hairpin RNA (shRNA)-mediated MMP11 knockdown in SGC-7901 GAC cells, we observed the changes of the biological behaviors of GAC cells. Our results indicated that the rate of positive expression of MMP11 was higher in GAC tissues than in ANCT (55.0 vs 30.0 percent, P=0.025). MMP11 expression had no association with the factors of age or gender of the GAC patients, or the size, pathological staging and lymph node metastases of the tumors (each P greater than 0.05). Furthermore, MMP11 knockdown inhibited the proliferative activities and invasive potential of SGC-7901 GAC cells with decreased expression of IGF-1, PCNA and VEGF. Taken together, our findings demonstrated that MMP11 expression was increased in GAC tissues, but did not correlate with the clinicopathologic features. Knockdown of MMP11 expression could inhibit the proliferation and invasion of GAC cells probably through down-regulation of the IGF-1 signaling pathway, suggesting that MMP11 might be a potential therapeutic target for the treatment of gastric cancer.