Exosome-transmitted miR-3124-5p promotes cholangiocarcinoma development via targeting GDF11.

Objective: Cholangiocarcinoma (CHOL) is a deadly cancer worldwide with limited available therapies. The aim of this study was to investigate key exosomal miRNAs and their functions in CHOL development. Methods: Serum exosomes were isolated from patients with CHOL and healthy controls, followed by miRNA sequencing for identifying differentially expressed miRNAs (DEMs) and their functions. Then, the expression of key DEMs was experimentally validated in exosomes from clinical CHOL patients and CHOL cells. The effects of overexpression of key DEMs on CHOL cell migration and proliferation were investigated. A key exosomal DEM miR-3124-5p was identified. The effects of overexpression or knockdown of exosomal miR-3124-5p on the proliferation, migration, and angiogenesis of human umbilical vein endothelial cells (HUVECs) were investigated. Moreover, the function of exosomal miR-3124-5p on tumor growth in vivo was explored. Results: A total of 632 exosomal DEMs were identified between CHOL and control samples. Target genes of DEMs were significantly enriched in pathways, such as the p53 signaling pathway. miR-3124-5p was upregulated in serum exosomes from CHOL patients and exosomes from CHOL cells, and overexpression of miR-3124-5p promoted RBE cell migration and viability. Moreover, overexpression of exosomal miR-3124-5p promoted the proliferation, migration, and angiogenesis of HUVECs, while knockdown of miR-3124-5p had the opposite effect. miR-3124-5p could target growth differentiation factor 11 (GDF11) and downregulate GDF11 expression. Furthermore, exosomal miR-3124-5p promoted tumor growth in vivo. Conclusions: Our findings revealed that exosome-encapsulated miR-3124-5p promoted the malignant progression of CHOL by targeting GDF11. Exosomal miR-3124-5p and GDF11 could be promising biomarkers or therapeutic targets for CHOL.

[Retracted] MicroRNA­760 inhibits cell proliferation and invasion of colorectal cancer by targeting the SP1­mediated PTEN/AKT signalling pathway.

Following the publication of this paper, it was drawn to the Editors' attention by a concerned reader that certain of the cell migration and invasion assay data shown in Figs. 2C and 5C were strikingly similar to data appearing in different form in other articles by different authors. Owing to the fact that the contentious data in the above article had already been published elsewhere, or were already under consideration for publication, prior to its submission to Molecular Medicine Reports, the Editor has decided that this paper should be retracted from the Journal. The authors were asked for an explanation to account for these concerns, but the Editorial Office did not receive a satisfactory reply. The Editor apologizes to the readership for any inconvenience caused. [the original article was published in Molecular Medicine Reports 16: 9692­9700, 2017; DOI: 10.3892/mmr.2017.7814].

HMGA1 Promotes Hepatic Metastasis of Colorectal Cancer by Inducing Expression of Glucose Transporter 3 (GLUT3).

BACKGROUND Colorectal cancer (CRC) is one of the most common cancers worldwide, and more than half of CRC patients have CRC liver metastasis (CRCLM). Mounting evidence indicates that high mobility group protein A1(HMGA1) is overexpressed in many cancer types, but its role in CRCLM has been obscure. MATERIAL AND METHODS Using immunohistochemistry, we assessed the expression of HMGA1 in 73 patients with CRCLM, and compared HMGA1 mRNA in 17 pairs of CRCs, CRCLM tissues, and normal liver tissues. The clinical significance of HMGA1 was evaluated by analyzing its correlation with the clinicopathological factors and overall survival (OS) rates. The function of HMGA1 in CRC invasion was investigated and the underlying mechanism of HMGA1-induced invasion was explored with in vitro experiments. RESULTS In CRCLMs, the high-HMGA1 and low-HMGA1 patients accounted for 53.42% and 46.58% of all patients, respectively. High HMGA1 expression in CRCLM was significantly associated with low OS rates. In vitro experiments demonstrated that HMGA1 promoted glucose transporter 3 (GLUT3) transcription and expression in CRC cells. GLUT3 was required in HMGA1-involved invasion, and GLUT3 expression was associated with poor prognosis of CRCLM. CONCLUSIONS High HMGA1 and GLUT3 expression in CRCLM was significantly correlated with poor prognosis of CRCLM. HMGA1 promoted CRC invasion by elevating GLUT3 transcription and expression.

PTPRF as a novel tumor suppressor through deactivation of ERK1/2 signaling in gastric adenocarcinoma.

BACKGROUND: Protein tyrosine phosphatase, receptor type F (PTPRF) is an important phosphatase playing roles in regulating cell growth, differentiation and oncogenic transformation. Overexpression of PTPRF has been observed in non-small cell lung cancer, but its clinical significance in other malignancies is still unknown. METHODS: We explored the expression pattern of PTPRF in gastric adenocarcinoma by using RT-qPCR and immunohistochemistry staining. The clinical significance of PTPRF was evaluated by univariate and multivariate analyses. Furthermore, the signaling pathways downstream of PTPRF was investigated by knockdown and overexpression assays combined with cellular studies. RESULTS: We found a remarkable down-regulation of PTPRF in gastric adenocarcinomas, which was significantly associated with advanced tumor TNM stages. Survival analysis showed that lower PTPRF level indicated a poorer overall survival of gastric adenocarcinoma patients. By conducting knockdown and overexpression studies in gastric adenocarcinoma cells, we revealed the role of PTPRF on inhibiting extracellular signal-regulated kinase-1/2 (ERK1/2) phosphorylation and its downstream signaling. Consistent with clinical findings, cellular results demonstrated that overexpressing PTPRF can significantly inhibit tumor migration and invasion, while silencing PTPRF showed opposite effects. CONCLUSION: In conclusion, patients with lower PTPRF expression in gastric adenocarcinoma tissues were more predisposed to advanced tumor stage and unfavorable prognosis.

Integrin αvß6 plays a bi-directional regulation role between colon cancer cells and cancer-associated fibroblasts.

Tumor microenvironment (TME) is the cellular environment in which tumor exists, and it contributes to tumor formation and progression. The TME is composed of tumor cells, stromal cells, cytokines, and chemotactic factors of which fibroblasts are the main cellular components. In our present study, we found that colorectal cancer (CRC) cells expressing integrin αvß6 clearly could induce morphological changes in inactive fibroblasts and increased the expression of activated fibroblast markers such as α-smooth muscle actin (α-SMA) and fibroblast-activating protein (FAP). Those activated fibroblasts in the TME are called cancer-associated fibroblasts (CAFs). In order to investigate the mechanism by which CRC cells expressing integrin αvß6 activated CAFs, a series of assays have been carried out in the follow-up. We found that CRC cells could secrete inactive transforming growth factor ß (TGF-ß); however, integrin αvß6 activated TGF-ß, which subsequently activated fibroblasts. This process was disrupted by knockdown of integrin αvß6. In contrast, activated fibroblasts could promote CRC cell invasion. In particular, the strengthening effect on expression of integrin αvß6 in colon cancer cells was obvious. Additionally, we found that CAFs could secrete stromal cell-derived factor-1 (SDF-1) and promote CRC cell metastasis in distant organs via the SDF-1/C-X-C chemokine receptor type 4 (CXCR4) axis. Taken together, we assumed that CRC cells and CAFs activated one another and worked together to promote cancer progression, with integrin αvß6 playing a role in the bi-directional regulation of these cells. Hence, integrin αvß6 may serve as a therapeutic target for the future CRC treatment.

MicroRNA­760 inhibits cell proliferation and invasion of colorectal cancer by targeting the SP1­mediated PTEN/AKT signalling pathway.

Colorectal cancer (CRC), one of the most commonly diagnosed types of cancer worldwide, is the third most prevalent and fourth most frequent cause of cancer­related mortality. Dysregulated microRNAs (miRNAs) have potential regulatory roles in the development and progression of various cancer types. Therefore, the investigation of the miRNAs involved in CRC formation and progression may lead to the development of highly effective therapeutic strategies for CRC. In the present study, miRNA­760 (miR­760) was frequently downregulated in CRC tissues and cell lines. The low levels of miR­760 expression were significantly correlated with the tumor size, lymph node metastasis and TNM stage of CRC. Functional assays revealed that restoring miR­760 expression inhibited CRC cell proliferation and invasion in vitro. The results of bioinformatics analysis, luciferase reporter assay, reverse transcription­quantitative polymerase chain reaction and western blot analysis suggested that specificity protein 1 (SP1) is a direct target of miR­760 in CRC. The high expression of SP1 in CRC tissues was inversely correlated with the expression of miR­760. Rescue experiments demonstrated that enforced SP1 expression rescued the tumor­suppressing effects of miR­760 on CRC cell proliferation and invasion. In addition, miR­760 overexpression is involved in the regulation of the PTEN/AKT signalling pathway. Collectively, the present data demonstrated that miR­760 directly targets SP1 to inactivate the PTEN/AKT signalling pathway, thus implicating miR­760 in the regulation of CRC cell proliferation and invasion. Therefore, miR­760 may be a novel biomarker and therapeutic target for CRC.

Prognostic significance of stromal SMYD3 expression in colorectal cancer of TNM stage I-III.

BACKGROUND: SET and MYND domain-containing protein 3 (SMYD3) is a histone methyltransferases and it promotes progression of many kinds of cancers including lung cancer, ovarian cancer and gastric cancer. In colorectal cancer (CRC), SMYD3 is proved to stimulate the proliferation of cancer cells, but the clinical significance of SMYD3 in CRC has not been elucidated. METHODS: In our study, we detected the expression of SMYD3 in CRC samples in TNM stage I-III with immunohistochemistry. The correlation between the expression of SMYD3 and the clinicopathological factors was analyzed with Chi-square test. The survival curve was displayed by Kaplan-Meier test and the statistical difference of subgroups was analyzed with log-rank test. Independent prognostic factors were identified by the Cox proportional hazards regression model. RESULTS: The percentage of high SMYD3 expression and low expression accounts for 47.98% and 52.02% respectively. High expression of SMYD3 was significantly associated with advance T stage (P=0.006) and lower survival rates (P=0.010), and it could be identified as an independent prognostic factor indicating unfavorable prognosis of patients with CRC (P=0.032, HR=1.98, 95% CI=1.06-3.70). CONCLUSIONS: SMYD3 high-expression is a high risk for poorer prognosis of CRC in TNM stage I-III. Our findings suggested that detecting SMYD3 may help stratify patients by risk more preciously and help make the individual treatment strategy.

Expression of Fibroblast Growth Factor 10 Is Correlated with Poor Prognosis in Gastric Adenocarcinoma.

Fibroblast growth factor receptor 2 (FGFR2) has been proved to be a significant prognostic factor and a potential therapeutic target in several types of cancer, including gastric cancer. FGFR2 consists two isoforms: FGFR2-IIIb and FGFR2-IIIc, which can be stimulated by different ligands and trigger different downstream signaling pathways. As a specific ligand to FGFR2-IIIb, fibroblast growth factor 10 (FGF10) is expressed in the gastric mesenchyme cell and is involved in stomach development and morphogenesis, but its expression and clinical significance is not well elucidated in gastric cancer. We analyzed FGF10 expression by immunohistochemistry in 178 samples of gastric adenocarcinoma (134 male and 44 female patients, with the average age of 63.2 years old and the average follow-up of 21.6 months). Using the arbitrarily scoring method based on positive cell percentage and staining intensity, we sub-divided the patients into FGF10 high-expression group (58 patients) and low-expression group (120 patients). We thus found that FGF10 expression is significantly associated with lymph node invasion (P = 0.004) and distant metastasis (P = 0.032). Importantly, FGF10 expression is an independent unfavorable prognostic factor (P = 0.042). Moreover, FGF10 knockdown significantly decreased the migration of cultured gastric adenocarcinoma cells, suggesting that FGF10 could promote the invasion of gastric adenocarcinoma. In conclusion, FGF10 expression was identified as a poor prognostic biomarker in gastric adenocarcinoma, and FGF10 could promote the invasion of gastric cancer cells. We suggest that FGF10 could be a potential and promising drug target in gastric adenocarcinoma.

Intraoperative sentinel lymph node mapping guides laparoscopic-assisted distal gastrectomy for distal gastric cancer.

AIMS: The aim of this retrospective study is to explore the effects of sentinel lymph node (SLN) mapping guided laparoscopic-assisted distal gastrectomy (LADG) for distal gastric cancer. METHODS: Two hundred patients were enrolled in this study. One hundred and one patients undergoing SLN guided LADG were designated as the SLN group. Ninety-nine patients having conventional LADG with D1 or D2 lymph node dissection were designated as the control group. Intraoperative and postoperative indicators such as the number of lymph nodes dissected, intraoperative and postoperative conditions, flow cytometry analysis of T lymphocyte subsets and natural killer (NK) cells, survival rates, recurrence rates and postoperative complications were investigated between these two groups. RESULTS: The number of lymph nodes dissected in the SLN group was significantly lesser than that in the control group. Furthermore, in the SLN group, the patients achieved better immunization status, improved intraoperative and postoperative conditions and decreased postoperative complications. There were no significant differences were found in the positive lymph nodes detected, the distance between proximal and distal cutting edge, postoperative survival or recurrence rates. CONCLUSIONS: SLN guided LADG for gastric cancer is a safe and effective method and could achieve an equal clinical effect as traditional laparoscopic D1 or D2 radical operation with less operation trauma and better recovery.

Expression of matrix metalloproteinase-9, cyclooxygenase-2 and vascular endothelial growth factor are increased in gastrointestinal stromal tumors.

This study is to investigate the expression of matrix metalloproteinase-9 (MMP-9), cyclooxygenase-2 (COX-2) and vascular endothelial growth factor (VEGF) in gastrointestinal stromal tumor (GIST). Immunohistochemistry was performed to detect the expression of MMP-9, COX-2 and VEGF. The expression of MMP-9, COX-2 and VEGF was compared among different clinicopathological features of GIST. Spearman rank correlation analysis was conducted to analyze the correlation among MMP-9, COX-2 and VEGF. The positive expression rates of MMP-9, COX-2 and VEGF were 76.9%, 84.6% and 82.7%. The expression levels of MMP-9, COX-2 and VEGF were significantly different among the clinicopathological features of growth pattern, tumor diameter, metastasis, mitotic count and central necrosis (P < 0.05). Their expression levels were higher in GIST tissues with higher levels of malignancy, tumor size, metastasis, mitotic count and central necrosis. However, their expression levels were not significantly different among age, gender, primary tumor site or CD117 expression. Additionally, there were positive correlations between COX-2 and VEGF (r = 0.612, P < 0.01), between COX-2 and MMP-9 (r = 0.592, P < 0.05), and between MMP-9 and VEGF (r = 0.690, P < 0.01). MMP-9, COX-2 and VEGF expression levels are increased in GIST tissues and related with clinicopathological features of GIST.

Expression and clinical significance of fibroblast growth factor 1 in gastric adenocarcinoma.

BACKGROUND: The clinical significance of fibroblast growth factor 1 (FGF1) has been revealed in several cancers, including ovarian cancer, breast cancer, and bladder cancer. However, the clinical significance of FGF1 in gastric adenocarcinoma has not been explored. PATIENTS AND METHODS: In our experiments, we systematically evaluated FGF1 expression in 178 cases of gastric adenocarcinoma with immunohistochemistry, and subsequently analyzed the correlation between FGF1 expression and clinicopathologic features. Moreover, FGF1 expression in tumor tissue and corresponding adjacent tissue was detected and compared by real-time polymerase chain reaction. The Kaplan-Meier method and the Cox-regression model were used with univariate and multivariate analysis, respectively, to evaluate the prognostic value of FGF1 in gastric adenocarcinoma. RESULTS: Higher FGF1 expression rate is 56.7% (101/178) in gastric adenocarcinoma. FGF1 expression in gastric adenocarcinoma was significantly higher than adjacent tissue (P<0.0001). Expression of FGF1 is significantly associated with lymph node invasion (P<0.001), distant metastasis (P=0.013), and differentiation (P=0.015). Moreover, FGF1 overexpression was closely related to unfavorable overall survival rate (P=0.021), and can be identified to be an independent unfavorable prognostic factor (P=0.004). CONCLUSION: FGF1 is an independent prognostic factor, indicating that FGF1 could be a potential molecular drug target in gastric adenocarcinoma.

Coexpression of cyclooxygenase-2 and vascular endothelial growth factor in gastrointestinal stromal tumor: possible relations to pathological parameters and clinical behavior.

BACKGROUND/AIMS: Currently, the clinicopathological significance of coexpression of cyclooxygenase-2 (COX-2) and vascular endothelial growth factor (VEGF) in gastrointestinal stromal tumors (GISTs) has not been fully described. METHODOLOGY: The present study was designed to investigate the co-expression of the two markers and its significance in 54 patients with GIST by means of immunohistochemistry. RESULTS: We demonstrated that the expressions of COX-2 and VEGF were significantly higher in malignant GIST than those in benign and potentially malignant GIST (p<0.01). A significant correlation was found between COX-2 and VEGF expression. In addition, the expressions of COX-2 and VEGF were significantly correlated with pattern of tumor growth, the size of tumors, and the central necrosis of tumors (p<0.01 or p<0.05). Five-year survival rates were much lower in patterns with high expression of COX-2 and VEGF than those with low expression (p<0.01). Overexpression of COX-2 and VEGF in GIST may enhance the possibility of growth, invasion, and metastasis. CONCLUSIONS: The levels of COX-2 and VEGF expression can be used as objective parameters in distinguishing benign from malignant, judging the malignant degree, and predicting the prognosis of patients with GIST.