TRIM15 Exerts Anti-Tumor Effects Through Suppressing Cancer Cell Invasion in Gastric Adenocarcinoma.

BACKGROUND Recent studies have shown that some members of the tripartite motif-containing protein (TRIM) family function as important regulators in several tumors. However, the clinical significance of TRIM15 in gastric adenocarcinoma has not been elucidated. In the present study, we aimed to examine the expression pattern of TRIM15 and explore whether the TRIM15 expression is correlated with clinicopathological characteristics of patients with gastric adenocarcinoma. MATERIAL AND METHODS The expression pattern of TRIM15 was examined in gastric adenocarcinoma tissues and adjacent normal stomach tissues by using immunohistochemistry staining. The prognostic role of TRIM15 in gastric cancer patients was evaluated by univariate and multivariate analyses. Clinical outcomes were assessed by the Kaplan-Meier analysis and log-rank test. The effects of TRIM15 on cancer cell proliferation and invasion were tested through cellular experiments. RESULTS TRIM15 was highly expressed in normal stomach tissues compared to tumor tissues. TCGA database showed that higher TRIM15 RNA transcription indicates poorer overall survival of gastric cancer patients. Besides, low expression of TRIM15 was significantly associated with advanced tumor invasion depth and advanced TNM stage. Moreover, gastric cancer patients with lower KDM5B expression had poorer overall survival, and TRIM15 was identified as an independent prognosis factor according to multivariate analysis. Using the gastric cancer cell lines, we found that overexpression of TRIM15 can inhibits tumor cell invasion. CONCLUSIONS Our study demonstrated that low expression of TRIM15 in gastric adenocarcinoma tissues was significantly associated with poorer prognosis of patients, indicating the potential of TRIM15 as a novel clinical biomarker and therapeutic target.

WW domain-binding protein 2: an adaptor protein closely linked to the development of breast cancer.

The WW domain is composed of 38 to 40 semi-conserved amino acids shared with structural, regulatory, and signaling proteins. WW domain-binding protein 2 (WBP2), as a binding partner of WW domain protein, interacts with several WW-domain-containing proteins, such as Yes kinase-associated protein (Yap), paired box gene 8 (Pax8), WW-domain-containing transcription regulator protein 1 (TAZ), and WW-domain-containing oxidoreductase (WWOX) through its PPxY motifs within C-terminal region, and further triggers the downstream signaling pathway in vitro and in vivo. Studies have confirmed that phosphorylated form of WBP2 can move into nuclei and activate the transcription of estrogen receptor (ER) and progesterone receptor (PR), whose expression were the indicators of breast cancer development, indicating that WBP2 may participate in the progression of breast cancer. Both overexpression of WBP2 and activation of tyrosine phosphorylation upregulate the signal cascades in the cross-regulation of the Wnt and ER signaling pathways in breast cancer. Following the binding of WBP2 to the WW domain region of TAZ which can accelerate migration, invasion and is required for the transformed phenotypes of breast cancer cells, the transformation of epithelial to mesenchymal of MCF10A is activated, suggesting that WBP2 is a key player in regulating cell migration. When WBP2 binds with WWOX, a tumor suppressor, ER transactivation and tumor growth can be suppressed. Thus, WBP2 may serve as a molecular on/off switch that controls the crosstalk between E2, WWOX, Wnt, TAZ, and other oncogenic signaling pathways. This review interprets the relationship between WBP2 and breast cancer, and provides comprehensive views about the function of WBP2 in the regulation of the pathogenesis of breast cancer and endocrine therapy in breast cancer treatment.

Aberrant expression of decoy receptor 3 in human breast cancer: relevance to lymphangiogenesis.

BACKGROUND: Decoy receptor 3 (DcR3), a decoy receptor against Fas ligand belonging to the tumor necrosis factor receptor superfamily, is overexpressed in some forms of cancer. It was recently reported that DcR3 could protect endothelial cells from apoptosis, implying a potential role in the development of vessels, whereas its role in the lymphangiogenesis remains unclear. In the present study, we studied the DcR3 expression and its relationship with the lymphatic microvessel density (LMVD) to investigate if it played a role in the lymph metastasis of human breast cancer. MATERIALS AND METHODS: Real-time polymerase chain reaction and immunohistochemistry were performed to measure the messenger RNA and protein expression of DcR3 in the breast cancer tissues, noncancerous counterparts, and axillary lymph node from 63 patients. LMVD in these specimens was assessed by counting the D2-40 labeled-microvessels. Furthermore, the correlations between DcR3 expression and LMVD and other clinicopathologic parameters were analyzed. RESULTS: DcR3 was overexpressed in the breast cancer tissue of 58 patients (92.1%) and was also expressed in vascular endothelial cells and tumor cells in the lymph nodes. LMVD in cancer tissue and lymph nodes were both positively correlated to the aberrant expression of DcR3. CONCLUSIONS: The relevance between DcR3 overexpression and LMVD revealed the existence of possible links between DcR3 and lymphangiogenesis. Based on these findings, it is important to further explore the regulation of lymphangiogenesis operated by the reverse tumor necrosis factor signaling of DcR3.

Extracellular matrix protein 1 is correlated to carcinogenesis and lymphatic metastasis of human gastric cancer.

BACKGROUND: Tumor-induced lymphangiogenesis is a crucial step in malignant invasion and metastasis. Extracellular matrix protein 1 (ECM1) was recently reported to play a role in lymphangiogenesis. In the present work, we aimed to evaluate the role of ECM1 in gastric cancer and examined whether aberrant expression of ECM1 increased the tumorigenic and metastatic potential of human gastric cancer. METHODS: The mRNA and protein expression of ECM1 in gastric cancer specimen and the noncancerous counterparts from 77 patients were detected by real-time PCR and immunohistochemistry staining. Lymphatic microvessel density (LMVD) in the corresponding serial sections was assessed by counting the lymphatic microvessels labelled by D2-40. The correlations between ECM1 expression, LMVD, and the clinicopathological parameters were examined. RESULTS: ECM1 protein expression was detected in 70.1% (54/77) of gastric cancer specimen, significantly higher than that in the corresponding counterparts (P<0.01). ECM1 mRNA in tumor specimen was also dramatically amplified. Elevated LMVD and ECM1 were positively correlated (P<0.01). In addition, ECM1 protein expression was also closely associated with depth of tumor invasion and TNM stage (P<0.05, respectively). CONCLUSIONS: ECM1 expression is aberrant elevated in tumor specimen and is closely related to the tumorigenic and metastatic potential of human gastric cancer. Thus, carrying out the protein examination may be beneficial to predict carcinogenesis and metastatic spread of human gastric cancer.

Hsa_circ_0003356 suppresses gastric cancer progression via miR-556-5p/FKBP5 axis.

BACKGROUND: CircRNAs are implicated in the tumorigenesis of various human cancers. This study aims to explore how circ_0003356 contributes to the development of gastric cancer (GC). METHODS: Circ_0003356 expression was analyzed in GSE184882 dataset and validated in our cohort of GC patients and human GC cell lines. The correlations between circ_0003356 levels and prognostic parameters were analyzed. The contribution of circ_0003356 in GC cell malignant behaviors such as cell survival, apoptosis and invasion were investigated by circ_0003356 overexpression in GC cell lines. The downstream targets of circ_0003356 were predicted and verified in vitro and in vivo. The in vivo function of circ_0003356 was studied as well in a xenograft mouse model. RESULTS: Circ_0003356 expressed at a low level in human GC tissues and cells, which was closely associated with poor outcome of GC patients. Circ_0003356 overexpression induced GC cell apoptosis while depressed the growing, migration and invasive abilities through miR-556-5p/FKBP5 axis. In vivo model showed retarded tumor growth when circ_0003356-overexpressed cells were inoculated. CONCLUSION: Circ_0003356 is identified as a potential biomarker of the prognosis of human gastric cancer, and circ_0003356/miR-556-5p/FKBP5 axis could be a promising target in gastric cancer treatment.

LncRNA HOXA10-AS functions as an oncogene by binding miR-6509-5p to upregulate Y-box binding protein 1 in gastric cancer.

Gastric cancer (GC) is one of the serious malignant diseases, accounting for several cases globally. The prevention, discovery and cure of GC depend on its molecular mechanism. In recent decades, it has been increasingly recognized that the long noncoding RNAs (lncRNAs) have been involved in GC progression. Therefore, the present study is aimed at identifying relevant lncRNAs that could act as biomarkers for GC prognosis. LncRNA HOXA10-AS is identified to be highly expressed in GC using the ENCORI database. Kaplan-Meier plot analysis indicated that the survival rate of the patient is associated with the expression of lncRNA HOXA10-AS. Interference of HOXA10-AS inhibited GC cell proliferation, migration, and invasion as well as facilitated GC apoptosis. The targets of HOXA10-AS included miR-6509-5p and Y-box binding protein 1 (YBX1). Specifically, HOXA10-AS downregulated miR-6509-5p in GC. An increase of miR-6509-5p inhibited GC cell growth. Meanwhile, miR-6509-5p interacted with YBX1 in GC. Together, lncRNA HOXA10-AS potentially acted as an oncogene through the lncRNA HOXA10-AS/miR-6509-5p/YBX1 signaling pathway in GC.

Stage cT3 low rectal cancer: analysis of prognostic factors.

Background: Whether all cT3 low rectal cancer patients should receive neoadjuvant chemoradiotherapy (nCRT) remains controversial. The depth of invasion beyond the muscularis propria of the cT3 rectal cancer is of great significance to the selection of a treatment plan and the evaluation of prognosis. Methods: A retrospective analysis was conducted of 187 patients with stage cT3 low rectal cancer, who had been treated at the Department of Colorectal Surgery, The First Affiliated Hospital of Xiamen University from June 2010 to December 2012. The patients were divided into the nCRT group (88 cases) and no-nCRT group (99 cases). Possible significant prognostic factors [i.e., primary tumor volume (PTV), cell differentiation, circumferential resection margin (CRM), nCRT, age, sex, carcinoembryonic antigen (CEA), lymph node status, surgical procedure, etc.] were collected for estimation of disease-free survival (DFS), distant metastases rate (DM), local recurrence rate (LR). Independent predictive factors or survival were determined using Cox proportional hazards model. Results: The mean PTV was 16.2±11.1 (2.07-72.68) cm3. In the univariate and multivariate analyses: nCRT hazards ratio (HR) =4.258, 95% confidence interval (CI): 1.912-9.483 (P<0.001); PTV HR =0.381, 95% CI: 0.181-0.804 (P=0.011); CRM HR =0.227, 95% CI: 0.097-0.532 (P=0.001). For the PTV ≤15 cm3 group, there were no significant differences between the nCRT and no-nCRT group in 3-year follow-up (P>0.05). For the PTV >15 cm3 group, there were significant differences between the nCRT and no-nCRT group in 3-year DFS (84.2% vs. 51.1%; P=0.001), DM (13.1% vs. 31.2%; P=0.017) and LR (2.9% vs. 26.6%; P=0.009). For the CRM negative group, there were significant differences between the nCRT and no-nCRT group in 3-year DFS (94.0% vs. 79.0%; P=0.008), LR (1.5% vs. 10.7%; P=0.028) and DM (4.5% vs. 13.5%; P=0.039). Conclusions: For stage cT3 low rectal cancer patients, nCRT, PTV, and CRM were independent prognostic factors. NCRT may improve the survival of PTV >15 cm3 patients, but may not have a significant effect on patient with PTV ≤15 cm3 and CRM negative. Direct surgery is recommended for this group of patients.

MicroRNA-215 Regulates the Apoptosis of HCT116 Colon Cancer Cells by Inhibiting X-Linked Inhibitor of Apoptosis Protein.

Background: X-linked inhibitor of apoptosis protein (XIAP) is the strongest member of the family of inhibitor of apoptosis protein. Studies found that the expression of XIAP in colon cancer tissue was significantly higher than that in adjacent tissues. Studies have shown that the expression of microRNA-215 (miR-215) was significantly lower than that of the adjacent tissues. This study investigated whether dysregulated miR-215 and XIAP play important roles in colon cancer cell apoptosis and the incidence of colon cancer. Materials and Methods: Forty-two patients with colorectal cancer (CRC) diagnosed and treated in the authors' hospital were selected. Human CRC cell line HCT116 and normal colonic mucosal epithelial cells (CMECs) were used. Luciferase reporter gene vector was constructed and dual-luciferase reporter gene assay was performed. HCT116 cells were cultured in vitro and divided into five groups: mimic normal control (NC) group, miR-215 mimic group, si-NC group, si-XIAP group, and miR-215 mimic + si-XIAP group. Western blot and polymerase chain reaction were conducted to examine XIAP and caspase-3. Apoptosis was detected by flow cytometry and cell proliferation was detected by cell counting kit-8 assay. Results: Compared with the adjacent tissues, the expression of miR-215 in colon cancer tissue was significantly lower, whereas the expression of XIAP in colon cancer tissue was significantly higher. The apoptosis rate and miR-215 expression level of HCT116 cells were lower than that of normal CMECs, whereas XIAP expression was significantly higher than that in normal colon mucosa epithelial cells. MiR-215 targeted the 3'-untranslated regions of XIAP and inhibited its expression. Overexpressing miR-215 and (or) silencing XIAP expression could significantly enhance the activity of caspase-9 and caspase-3, and promote the apoptosis of HCT116 cells. Conclusion: MiR-215 inhibited the expression of XIAP and promoted the apoptosis of HCT116 cells.

Oncogenic long intervening noncoding RNA Linc00284 promotes c-Met expression by sponging miR-27a in colorectal cancer.

Emerging evidences suggest that long noncoding RNA (lncRNA) plays a vital role in tumorigenesis and cancer progression. Here, the aim of this study is to investigate the biological function of long intervening noncoding RNA Linc00284 in colorectal cancer (CRC). The expression levels of Linc00284, miR-27a and c-Met were evaluated by qPCR and/or Western blotting. Immunohistochemistry was used to detect the expression of Ki67 and Phh3 in tumor tissues. The interaction between Linc00284, miR-27a and c-Met was validated by luciferase reporter assay and RNA immunoprecipitation (RIP) assay. Cell function experiments, including CCK-8, wound-healing and transwell invasion assays, were conducted. The in vivo studies were performed with the subcutaneous tumor xenograft mouse models. Our findings reveal that Linc00284 is upregulated in CRC tissues and colorectal cancer cell lines HCT116 and SW480 in comparison with corresponding para-carcinoma tissues and human fetal colonic mucosa cells FHC. High expression of Linc00284 in tumor tissues is associated with tumor metastasis and predicts a poor clinical outcome in CRC patients. Serum Linc00284 is increased, while miR-27a is decreased in CRC patients compared to healthy controls. ROC curve analysis indicates that serum Linc00284 and miR-27a produce the area under the curve (AUC) value of at 0.8151 and 0.7316 in patients with colorectal cancer compared to healthy individuals, respectively. Additionally, results in vitro and in vivo experiments suggest that Linc00284 silencing significantly suppresses CRC cell proliferation and/or invasion. Mechanistically, Linc00284 promotes c-Met expression by acting as miR-27a sponge, leading to the activation of downstream signaling pathways, thereby causing malignant phenotypes of CRC cells. Taken together, Linc00284 exhibits oncogenic function and the disturbance of Linc00284/miR-27a/c-Met regulatory axis contributes to CRC progression, providing new insight into the pathogenesis of colorectal cancer. Importantly, the expression levels of serum Linc00284 and miR-27a may serve as clinical biomarkers for CRC diagnosis.

Amyloid precursor protein promotes the migration and invasion of breast cancer cells by regulating the MAPK signaling pathway.

To verify whether amyloid precursor protein (APP) affects the migration and invasion of breast cancer cell lines, and to understand its underlying mechanisms, epithelial­mesenchymal transition (EMT), the mitogen­activated protein kinase (MAPK) signaling pathway and the matrix metalloproteinase (MMP) family were investigated in MDA­MB­231, MCF­7 and BT474 human breast cancer cells. Breast cancer cell lines were transfected with plasmids containing APP coding sequences (pEGFP­n1­APP) and APP short hairpin RNA (pENTR APP shRNA). APP overexpression efficiency, knockout efficiency and the expression levels of related genes were tested using reverse transcription­quantitative PCR (RT­qPCR) and western blot analyses. The effects of APP and mitogen­activated protein kinase kinase (MEK) inhibitor on cell migration and invasion were examined using Transwell assays. The results demonstrated that APP was significantly upregulated in the pEGFP­n1­APP group (P<0.05), and significantly downregulated in the pENTR APP shRNA group (P<0.05), compared with the control group. APP overexpression increased the migratory and invasive ability of human breast cancer cells (P<0.05), whereas APP silencing significantly inhibited cell migration and invasion (P<0.05). RT­qPCR and western blot analysis results suggested that APP overexpression significantly increased the expression of MMP­9, MMP­2, MMP­3, N­cadherin and vimentin (P<0.05). In addition, the enhanced expression of APP markedly affected the phosphorylation of mitogen­activated protein kinase kinase kinase 11 (MLK3), mitogen­activated protein kinase kinase 4 (MEK4) and mitogen­activated protein kinase 10 (JNK3; P<0.05). Additionally, APP overexpression had no effect on the total expression levels of MLK3, MEK4, and JNK3; however, APP overexpression significantly decreased the expression levels of E­cadherin and cytokeratin (P<0.05). Conversely, APP silencing had the opposite effects. When cells were treated with the MEK inhibitor PD0325901, the expression of APP was not altered, nor was the expression levels of MEK and its upstream signaling molecules. Taken together, the present findings suggested that APP could affect the migration and invasion of human breast cancer cells by mediating the activation of the MAPK signaling pathway, thereby promoting the EMT process.

[Application of right-to-lateral approach in laparoscopic-assisted radical gastrectomy].

OBJECTIVE: To explore the technical feasibility, safety, and short-term clinical efficacy of right-to-lateral approach in laparoscopic-assisted radical gastrectomy. METHODS: Clinicopathological data of 178 gastric cancer patients undergoing laparoscopic-assisted radical gastrectomy, including 92 patients with right-to-lateral approach(R-LG group) and 86 cases with left-to-lateral approach (L-LG group), in our department from October 2010 to September 2013 were analyzed retrospectively. Short-term efficacy and complication morbidity were compared between R-LG group and L-LG group according to body mass index (BMI). RESULTS: For those patients with BMI ≥ 24 kg/m², the R-LG group (35 cases) had shorter mean operation time, less intraoperative blood loss, shorter painkiller used time than L-LG group (31 cases)[(227 ± 17) min vs. (262 ± 23) min, (73 ± 9) ml vs. (84 ± 8) ml and (2.1 ± 0.1) d vs. (2.6 ± 0.4) d, all P<0.05]. The average time to ambulation and recovery time of peristalsis in the R-LG group were faster than those in L-LG group [(2.2 ± 0.2) d vs. (2.8 ± 0.6) d and (3.6 ± 0.3) d vs. (4.2 ± 0.5) d, all P<0.05]. The R-LG group had more dissected lymph nodes per patient (35 ± 4) than the L-LG group (30 ± 5) with significant difference (P<0.05). There were no significances in postoperative hospital stay, postoperative complication morbidity and hospitalization expenses between R-LG and L-LG group (all P>0.05). For those patients with BMI<24 kg/m², there were no significant differences in all above parameters between R-LG group (57 cases) and L-LG group (55 cases). No mortality and recurrence was observed during follow-up of 3 to 24 months. CONCLUSION: Right-to-lateral approach in laparoscopic-assisted radical gastrectomy is a safe and feasible procedure, especially for the obesity patients, which can shorten the operation time, decrease intraoperative blood loss, lead to a faster postoperative recovery and harvest more lymph nodes as compared to L-LG procedure.