MicroRNAs (miRNAs) are a type of small non-coding RNAs that are often play important roles in carcinogenesis, but the carcinogenic mechanism of miRNAs is still unclear. This study will investigate the function and the mechanism of miR-638 in carcinoma (GC). The expression of miR-638 in GC and the DNA copy number of miR-638 were detected by real-time PCR. The effect of miR-638 on cell proliferation was measured by counting kit-8 assay. Different assays, including bioinformatics algorithms (TargetScan and miRanda), luciferase report assay and Western blotting, were used to identify the target gene of miR-638 in GC. The expression of miR-638 target gene in clinical CRC tissues was also validated by immunohistochemical assay. From this research, we found that miR-638 was downregulated in GC tissues compared with corresponding noncancerous tissues (NCTs), and the DNA copy number of miR-638 was lower in GC than NCTs, which may induce the corresponding downregulation of miR-638 in GC. Ectopic expression of miR-638 inhibited GC cell growth in vitro. Subsequently, we identified that PLD1 is the target gene of miR-638 in GC, and silencing PLD1 expression phenocopied the inhibitory effect of miR-638 on GC cell proliferation. Furthermore, we observed that PLD1 was overexpressed in GC tissues, and high expression of PLD1 in GC predicted poor overall survival. In summary, we revealed that miR-638 functions as a tumor suppressor in GC through inhibiting PLD1.
3' Untranslated Regions ; genetics ; Apoptosis ; genetics ; Base Sequence ; Cell Line, Tumor ; Cell Proliferation ; genetics ; Down-Regulation ; genetics ; Humans ; MicroRNAs ; genetics ; Phospholipase D ; genetics ; Prognosis ; Stomach Neoplasms ; diagnosis ; enzymology ; genetics ; pathology

OBJECTIVETo study the expression of phospholipase C epsilon-1(PLCE1) and its clinical significance in gastric cancer.

METHODSSurgical specimens were collected from 125 patients who underwent radical gastrectomy between 2005 and 2007 in the Zhejiang Provincial Peoples' Hospital. Expression level of PLCE1 protein was measured by immunohistochemistry in these 125 surgical specimens, which included primary gastric cancer and matched adjacent normal gastric mucosa tissues, and then 41 pairs of above specimens were selected randomly to examine the expression level of PLCE1 mRNA by quantitative reverse transcription PCR(qRT-PCR).

RESULTSImmunohistochemistry and qRT-PCR showed that both protein and mRNA level of PLCE1 were up-regulated in gastric cancer compared with paired normal gastric mucosa. Univariate analysis demonstrated that the expression of PLCE1 was significantly associated with differentiation degree, invasion depth, lymph node metastasis, distant metastasis, and TNM stage (all P<0.01). The 5-year survival rate of positive PLCE1 group was significantly lower as compared to negative group (31.2% vs. 54.0%, P<0.01). However, the expression of PLCE1 was not an independent prognostic factor for gastric cancer (P>0.05).

CONCLUSIONSPLCE1 is up-regulated in gastric cancer, which is associated with the malignant biological behaviors of gastric cancer. High expression of PLCE1 suggests poor prognosis.

Biomarkers, Tumor ; analysis ; Gastrectomy ; Humans ; Immunohistochemistry ; Lymphatic Metastasis ; Neoplasm Staging ; Phosphoinositide Phospholipase C ; metabolism ; Prognosis ; RNA, Messenger ; Reverse Transcriptase Polymerase Chain Reaction ; Stomach Neoplasms ; enzymology ; pathology ; Survival Rate ; Up-Regulation

Although medical treatment has been shown to improve quality of life and prolong survival, no significant progress has been made in the treatment of advanced gastric cancer (AGC) within the last two decades. Thus, the optimum standard first-line chemotherapy regimen for AGC remains debatable, and most responses to chemotherapy are partial and of short duration; the median survival is approximately 7 to 11 months, and survival at 2 years is exceptionally > 10%. Recently, remarkable progress in tumor biology has led to the development of new agents that target critical aspects of oncogenic pathways. For AGC, many molecular targeting agents have been evaluated in international randomized studies, and trastuzumab, an anti-HER-2 monoclonal antibody, has shown antitumor activity against HER-2-positive AGC. However, this benefit is limited to only ~20% of patients with AGC (patients with HER-2-positive AGC). Therefore, there remains a critical need for both the development of more effective agents and the identification of molecular predictive and prognostic markers to select those patients who will benefit most from specific chemotherapeutic regimens and targeted therapies.
Angiogenesis Inhibitors/therapeutic use ; Animals ; Antineoplastic Agents/*therapeutic use ; Humans ; *Molecular Targeted Therapy ; Protein Kinase Inhibitors/therapeutic use ; Receptor, Epidermal Growth Factor/antagonists & inhibitors/metabolism ; Receptor, erbB-2/antagonists & inhibitors/metabolism ; Signal Transduction/drug effects ; Stomach Neoplasms/*drug therapy/enzymology/genetics/pathology ; Treatment Outcome

OBJECTIVETo study the role of arginase-1 (Arg-1) expression in differential diagnosis of hepatocellular carcinoma (HCC), Arg-1 staining pattern in clear cell neoplasm (HCC and non-HCC) and Arg-1 expression in non-hepatocellular tumors.

METHODSSeventy-eight cases of HCC (including 8 cases of clear cell type and 70 cases of non- clear cell type) and 246 cases of non-hepatocellular neoplasms (including 29 cases of metastatic tumors such as breast cancer, nasopharyngeal carcinoma and neuroendocrine carcinoma, 77 cases of tumors with clear cell changes such as malignant melanoma, clear cell renal cell carcinoma and alveolar soft part sarcoma, and 140 cases of other types of tumors such as ovarian endometrioid adenocarcinoma, pituitary tumor and thyroid papillary carcinoma) were studied.Immunohistochemical study for Arg-1 was performed on the paraffin-embedded tumor tissue.

RESULTSIn HCC, Arg-1 demonstrated both cytoplasmic and nuclear staining, with an overall sensitivity of 96.2% (75/78).In well, moderately and poorly differentiated HCC, the sensitivity was 15/15, 100% (41/41) and 86.4% (19/22), respectively. That was in contrast to negative staining for Arg-1 in all the 29 cases of metastatic tumors studied. The sensitivity, specificity, positive predictive value and negative predictive value of Arg-1 in distinguishing HCC from metastatic tumors was 96.2%, 100%, 100% and 90.6%, respectively. Cytoplasmic and membranous staining was observed in clear cell type of HCC. The overall sensitivity of Arg-1 expression in the 77 cases of tumors with clear cell changes was 14.3% (11/77), including 8/15 for malignant melanoma, 2/4 for ovarian clear cell carcinoma and 1/1 gall bladder adenocarcinoma with clear cell component.In malignant melanoma and ovarian clear cell carcinoma, only cytoplasmic staining was demonstrated. There was no expression of Arg-1 in the 140 cases of other tumor types studied.

CONCLUSIONSArg-1 is a sensitive and specific marker for HCC.It is a potentially useful immunohistochemical marker in distinguishing HCC from metastatic tumors. Though also expressed in malignant melanoma and ovarian clear cell carcinoma, Arg-1 shows a different staining pattern as compared with that in HCC.

Adenocarcinoma ; enzymology ; Adult ; Aged ; Arginase ; metabolism ; Carcinoma, Hepatocellular ; enzymology ; pathology ; secondary ; Cell Differentiation ; Diagnosis, Differential ; Female ; Gallbladder Neoplasms ; enzymology ; Humans ; Liver Neoplasms ; enzymology ; pathology ; secondary ; Male ; Melanoma ; enzymology ; Middle Aged ; Ovarian Neoplasms ; enzymology ; Stomach Neoplasms ; enzymology ; pathology

OBJECTIVETo investigate the association of AKR1B10 expression in gastric cancer tissues with clinicopathologic features and prognosis of gastric cancer patients.

METHODSReal-time polymerase chain reaction (RT-PCR) was conducted to detect AKR1B10 mRNA expression in gastric cancer and adjacent gastric mucosa tissues (n=36). AKR1B10 protein expression was measured by immunohistochemistry in primary gastric cancer tissues (n=100) and non-tumorous gastric mucosa tissues (n=70).

RESULTSRT-PCR results confirmed that AKR1B10 was significantly down-regulated in gastric cancer tissues compared with that in paired adjacent mucosa [8.3% (3/36) vs. 91.7% (33/36), P=0.000]. Immunohistochemistry revealed that the percentage of AKR1B10 positive specimens in gastric carcinoma was lower than that in normal specimens [33.0% (33/100) vs. 92.9% (65/70), P=0.000]. The frequencies of positive AKR1B10 in patients was significantly correlated with tumor size (P=0.000), invasive depth (P=0.004), lymph node metastasis (P=0.028), distant metastasis (P=0.031) and TNM stages (P=0.000). The 5-year survival rate of positive AKR1B10 group was significantly higher as compared to negative group (60.6% vs. 32.8%, P<0.01).

CONCLUSIONThe down-regulation of AKR1B10 expression in gastric cancer may be associated with the progress of gastric cancer is suggestive of poor prognosis.

Adult ; Aged ; Aged, 80 and over ; Aldehyde Reductase ; genetics ; metabolism ; Female ; Gastric Mucosa ; enzymology ; pathology ; Humans ; Male ; Middle Aged ; Prognosis ; RNA, Messenger ; genetics ; Stomach Neoplasms ; diagnosis ; enzymology ; pathology

Animals ; Carcinoma, Squamous Cell ; genetics ; Colorectal Neoplasms ; genetics ; metabolism ; Enzyme Activation ; Esophageal Neoplasms ; genetics ; Genome-Wide Association Study ; Head and Neck Neoplasms ; genetics ; Humans ; Neoplasms ; chemically induced ; enzymology ; genetics ; Phosphoinositide Phospholipase C ; chemistry ; genetics ; metabolism ; physiology ; Signal Transduction ; Skin Neoplasms ; chemically induced ; enzymology ; Stomach Neoplasms ; genetics ; Urinary Bladder Neoplasms ; metabolism ; pathology ; ras Proteins ; metabolism

OBJECTIVETo study the effects of lysyl oxidase (LOX) on the migration and adhesion of the human gastric cancer cell line HGC-27 cells in vitro.

METHODSThe human gastric cancer cell line HGC-27 cells were cultured in vitro, and treated with different concentration of β-aminopropionitrile (BAPN). The ability of migration was assessed by wound-healing assay. The ability of adhesion was detected by homogenous and heterogeneous adhesion experiments.

RESULTSCompared that with 0 mmol/L BAPN, the ability of migration of the cells after treatment with 0.2 mmol/L BAPN was descended at 8, 24, 32 and 48 h; the number of cells with homogeneous adhesion was increased from (6.97 ± 0.07) × 10(3)/ml to (7.78 ± 0.11) × 10(3)/ml; and the number of cells with heterogeneous adhesion was decreased from (8.98 ± 0.15) × 10(3)/ml to (8.35 ± 0.10) × 10(3)/ml, both < 0.05. Compared with that of cells treated with 0 mmol/L and 0.2 mmol/L BAPN, the migration ability of cells after treatment with 0.3 mmol/L BAPN was descended at 8, 24, 32 and 48 h; the number of cells with homogeneous adhesion was raised to (8.02 ± 0.11) × 10(3)/ml and the number of cells with heterogeneous adhesion was down to (7.93 ± 0.07) × 10(3)/ml (P < 0.05).

CONCLUSIONLOX may promote the metastasis of cancer cells by enhancing invasion, increasing heterogeneous adhesion and decreasing homogeneous adhesion.

Aminopropionitrile ; administration & dosage ; pharmacology ; Cell Adhesion ; drug effects ; Cell Line, Tumor ; Cell Movement ; drug effects ; Dose-Response Relationship, Drug ; Humans ; Neoplasm Invasiveness ; Protein-Lysine 6-Oxidase ; antagonists & inhibitors ; metabolism ; physiology ; Stomach Neoplasms ; enzymology ; pathology

OBJECTIVETo investigate the effects of silencing heparanase (HPA) on growth, angiogenesis and metastasis of human gastric carcinoma transplanted in nude mice.

METHODSHuman gastric carcinoma SGC-7901 cells and those cells with silenced HPA (gastric carcinoma SGC-7901-HPA(-)) were separately transplanted subcutaneously in 6 nude mice. The time, size and speed of tumor growth were recorded. RT-PCR and Western-blot were used to detect the expression of HPA mRNA and protein in the subcutaneous tumors of the two groups. Immunohistochemical staining was used to detect microvessel density (MVD) in the subcutaneous tumors of the two groups. Cells of the subcutaneous transplanted tumors of the two groups were separately injected into the peritoneal cavity of nude mice, 6 mice each. The growth of metastatic tumors in nude mice was observed.

RESULTSHuman gastric carcinoma SGC-7901 cells and SGC-7901-HPA(-) cells were subcutaneously inoculated in nude mice, and tumors appeared at 4 days and 7 days after inoculation, respectively. The MVD was (20.69 ± 1.20)/HP and (11.35 ± 1.94)/HP, respectively (P < 0.05). The expressions of HPA mRNA and protein of the subcutaneously transplanted SGC-7901-HPA(-) tumor were decreased. Four voluminous metastatic tumors caused by SGC-7901 cells occurred in 3 mice in the liver, right kidney, omentum and intestine. Two smaller abdominal metastatic tumors of SGC-7901-HPA(-) cells were found in the liver and right kidney.

CONCLUSIONSilencing HPA can inhibit the tumor growth, angiogenesis and metastasis of human gastric cancer in nude mice. It suggests that HPA might become a new target for prevention and treatment of gastric cancer.

Adenocarcinoma ; blood supply ; enzymology ; genetics ; pathology ; secondary ; Animals ; Cell Line, Tumor ; Gene Silencing ; Glucuronidase ; biosynthesis ; genetics ; physiology ; Humans ; Kidney Neoplasms ; secondary ; Liver Neoplasms ; secondary ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Microvessels ; pathology ; Neoplasm Transplantation ; Neovascularization, Pathologic ; RNA, Messenger ; metabolism ; Stomach Neoplasms ; blood supply ; enzymology ; genetics ; pathology

Rebamipide a gastroprotective drug, is clinically used for the treatment of gastric ulcers and gastritis, but its actions on gastric cancer are not clearly understood. Phospholipase D (PLD) is overexpressed in various types of cancer tissues and has been implicated as a critical factor in inflammation and carcinogenesis. However, whether rebamipide is involved in the regulation of PLD in gastric cancer cells is not known. In this study, we showed that rebamipide significantly suppressed the expression of both PLD1 and PLD2 at a transcriptional level in AGS and MKN-1 gastric cancer cells. Downregulation of PLD expression by rebamipide inhibited its enzymatic activity. In addition, rebamipide inhibited the transactivation of nuclear factor kappa B (NFkappaB), which increased PLD1 expression. Rebamipide or PLD knockdown significantly suppressed the expression of genes involved in inflammation and proliferation and inhibited the proliferation of gastric cancer cells. In conclusion, rebamipide-induced downregulation of PLD may contribute to the inhibition of inflammation and proliferation in gastric cancer.
Alanine/*analogs & derivatives/pharmacology ; Cell Line, Tumor ; Cell Proliferation/drug effects ; Down-Regulation/*drug effects ; Gene Expression Regulation, Neoplastic/*drug effects ; Humans ; Inflammation/*enzymology/genetics/pathology ; Isoenzymes/genetics/metabolism ; NF-kappa B/metabolism ; Phospholipase D/*genetics/metabolism ; Promoter Regions, Genetic/genetics ; Quinolones/*pharmacology ; Stomach Neoplasms/*enzymology/genetics/*pathology ; Transcription, Genetic/drug effects

Humans ; Kisspeptins ; Lymphatic Metastasis ; genetics ; Matrix Metalloproteinase 9 ; genetics ; RNA, Messenger ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Stomach Neoplasms ; enzymology ; metabolism ; pathology ; Tumor Suppressor Proteins ; genetics