N6-methyladenosine-modified microRNA-675 advances the development of gastrointestinal stromal tumors via inhibiting myosin phosphatase targeting protein 1.

RNA N6-methyladenosine (m6A) modifications influence gastrointestinal stromal tumors (GISTs) development, but the detailed molecular mechanisms have not been fully studied. Here, microRNA-675 was found to be aberrantly elevated in cancerous tissues and cells of GISTs, compared to the corresponding normal counterparts, and GISTs patients with high-expressed microRNA-675 have worse outcomes. Additional experiments confirmed that silencing of microRNA-675 hindered cell division, mobility and tumorigenesis in vitro and in vivo, whereas triggered apoptotic cell death in GISTs cells. Furthermore, microRNA-675-ablation increased the expression levels of myosin phosphatase targeting protein 1 (MYPT1) to inactivate the tumor-initiating RhoA/NF2/YAP1 signal pathway, and downregulation of MYPT1 recovered the malignant phenotypes in microRNA-675-silenced GISTs cells. In addition, we evidenced that METTL3-mediated m6A modifications were essential for sustaining the stability of microRNA-675, and silencing of METTL3 restrained tumorigenesis of GISTs cells by regulating the microRNA-675/MYPT1 axis. To summarize, theMETTL3/m6A/microRNA-675/MYPT1 axis could be used as novel biomarkers for the diagnosis and treatment of GISTs.

Differential expression of proteomics models of colorectal cancer, colorectal benign disease and healthy controls.

BACKGROUND: Colorectal cancer (CRC) is often diagnosed at a late stage with concomitant poor prognosis. The hypersensitive analytical technique of proteomics can detect molecular changes before the tumor is palpable. The surface-enhanced laser desorption/ionization-time of flight-mass spectra (SELDI-TOF-MS) is a newly-developed technique of evaluating protein separation in recent years. The protein chips have established the expression of tumor protein in the serum specimens and become the newly discovered markers for tumor diagnosis. The objective of this study was to find new markers of the diagnosis among groups of CRC, colorectal benign diseases (CBD) and healthy controls. The assay of SELDI-TOF-MS with analytical technique of protein-chip bioinformatics was used to detect the expression of protein mass peaks in the sera of patients or controls. One hundred serum samples, including 52 cases of colorectal cancer, 27 cases of colorectal benign disease, and 21 cases of healthy controls, were examined by SELDI-TOF-MS with WCX2 protein-chips. RESULTS: The diagnostic models (I, II and III) were setup by analyzed the data and sieved markers using Ciphergen - Protein-Chip-Software 5.1. These models were combined with 3 protein mass peaks to discriminate CRC, CBD, and healthy controls. The accuracy, the sensitivity and the particularity of cross verification of these models are all highly over 80%. CONCLUSIONS: The SELDI-TOF-MS is a useful tool to help diagnose colorectal cancer, especially during the early stage. However, identification of the significantly differentiated proteins needs further study.

MiR-1228 promotes breast cancer cell growth and metastasis through targeting SCAI protein.

Breast cancer is the most common cancer in women around the world. However, the molecular mechanisms underlying breast cancer pathogenesis are only partially understood. Here, in this study, we found that miR-1228 was up-regulated in breast cancer cell lines and tissues. Ectopic expression of miR-1228 mimics leads to promoted cell growth, invasion and migration. Using bioinfomatic analysis and 3'UTR luciferase reporter assay, we determined SCAI can be directly targeted by miR-1228, which can down-regulate endogenous SCAI protein level. Furthermore, our findings demonstrate that SCAI was down-regulated in breast cancer cell lines and tissues. Rescue experiment demonstrated that miR-1228 promoted cell growth is attenuated by over-expression of MOAP1 and miR-1228 promoted cell invasion and migration can be attenuated by over-expression of SCAI. Taken together, this study provides evidences that miR-1228 serves as an oncogene to promote breast cancer proliferation, invasion and migration, which may become a critical therapeutic target for breast cancer treatment.

miR-125a-5p inhibits cell proliferation and induces apoptosis in colon cancer via targeting BCL2, BCL2L12 and MCL1.

MicroRNAs (miRNAs) are small non-coding RNAs that function as regulators of gene expression. MiR-125 is a family of miRNAs that have been shown to be involved in various cancer types. In this study, for the first time, we showed that miR-125a-5p was specifically down-regulated in both colon cancer tissue and colon cancer cell lines. The tumor suppressor role of miR-125a-5p in colon cancer was supported by the observation that overexpression of miR-125a-5p inhibited cell proliferation and induced cell apoptosis in colon cancer cells. We also confirmed that in colon cancer cells, anti-apoptotic genes BCL2, BCL2L12 and Mcl-1 were direct targets of miR-125a-5p, and they were down-regulated by miR-125a-5p overexpression. Furthermore, restoration of BCL2, BCL2L12 and Mcl-1 expression in colon cancer cells could partially reverse the cell proliferation inhibition and apoptosis stimulation caused by miR-125a-5p overexpression, indicating that miR-125a-5p inhibits cell proliferation and induces apoptosis in colon cancer cells via targeting BCL2, BCL2L12 and Mcl-1.

Anti-proliferative effect of an extract of the root of Polygonum multiflorum Thunb. on MCF-7 human breast cancer cells and the possible mechanisms.

The root of Polygonum multiflorum Thunb. (PM) is utilized to treat many diseases associated with aging. Research also indicates that PM inhibits the proliferation of certain types of cancer cells. The aim of the present study was to evaluate the inhibitory effect of PM extract (PME) on the proliferation of MCF-7 cells and to investigate the underlying mechanisms. Inhibition of the proliferation of MCF-7 cells was determined by the MTT assay. Cell cycle distribution and apoptotic rates were evaluated by flow cytometry, and cell cycle and apoptosis-related protein expression was assessed by Western blotting. Apoptotic characteristics of MCF-7 cells were detected by transmission electron microscopy. The present study showed that PME at doses of 100, 150, 200 and 250 µg/ml significantly inhibited proliferation of MCF-7 cells in a time- and dose-dependent manner. Flow cytometry showed that the cell apoptotic rates were 9.1 ± 1.67 and 17.7 ± 2.93% after treatment with 100 and 200 µg/ml PME for 48 h, respectively. The proportions of cells in the G2/M phase were 37.9 ± 1.47 and 42.0 ± 1.71% after treatment with 100 and 200 µg/ml PME for 24 h, respectively. Western blot analysis showed that PME down-regulated the protein expression of Cdc25B and Cdc25C phosphatases accompanied by an increase in phospho-Cdk1, and PME promoted cytochrome c release from mitochondria into the cytosol to activate caspase-9. The present study demonstrated that PME inhibited MCF-7 cell proliferation by inducing cell cycle arrest in the G2/M phase and promoting cell apoptosis. The effects of PME on MCF-7 cells were associated with the modulation of the expression levels of proteins involved in the cell cycle and apoptosis. These data suggest that PME has promise as a treatment against breast cancer by inhibiting the proliferation of cancer cells.

Effects of raspberry phytochemical extract on cell proliferation, apoptosis, and serum proteomics in a rat model.

The red raspberry extract possesses potent antioxidant capacity and anticancerous activity in vitro and in vivo. The objective of this study was to determine whether red raspberry extract affected the cell cycle, angiogenesis, and apoptosis in hepatic lesion tissues from a rat model induced by diethylnitrosamine (DEN) as well as changes of serum proteomics. Rats were treated with red raspberry extract (0.75, 1.5, or 3.0 g/kg of body weight) by gavage starting 2 h after DEN administration and continued for 20 wk. Red raspberry extract inhibited cell proliferation, vascular endothelial growth factor VEGF expression, and induced apoptosis in the hepatic lesion tissues. In addition, 2 protein peaks (2597.93 and 4513.88 m/z) were identified to differentially express in the 3.0 g/kg body weight and positive control groups by serum proteomics. These results suggest that a dietary supplement with red raspberry effectively protects against chemically induced hepatic lesions in rats.

Antiangiogenetic effects of 4 varieties of grapes in vitro.

The purpose of this study was to investigate the inhibitory effects of grapes on the human umbilical vein endothelial (HUVE) cells' capillary tube formation and matrix metalloproteinase-2 (MMP-2) expression secreted into the medium. Four different grape varieties (Concord, Niagara, Chardonnay, and Pinot Noir) were extracted using 80% acetone and the extracts were stored at -80 degrees C. The total amount of phenolics and flavonoids for each of the 4 grape varieties were determined by spectrophotometry. Grape extracts were co-cultured with HUVE cells on Matrigel and inhibitory effects on tube formation were observed under a microscope. The inhibitory effects of grape extracts on MMP-2 expression were examined by zymogram. All 4 grape varieties inhibited the tube formation of HUVE cells in a dose-dependent manner on Matrigel. Except for Chardonnay, the other 3 grape varieties completely inhibited secretion of MMP-2 at 20 mg/mL. There was a significant positive relationship between the total phenolics and flavonoids and antiangiogenetic activities. The grapes tested have the potential to inhibit angiogenesis mainly by their phenolics and flavonoids contents, which partly contribute to their cancer chemopreventive efficacy.

Fresh raspberry phytochemical extract inhibits hepatic lesion in a Wistar rat model.

BACKGROUND: Red raspberry possesses potent antioxidant capacity and antiproliferative activity against cancer in vitro. METHODS: The objective of this study was to determine the protective effects of raspberry 80% acetone extract in a rat hepatic lesions model induced by diethylnitrosamine (DEN). Rats were treated with the red raspberry extract (0.75, 1.5 or 3.0 g/kg of body weight) by gavage starting 2 h after DEN administration and continuing for 20 weeks. RESULTS: A dose-dependent inhibition by red raspberry extract of DEN-induced hepatic nodule formation which stands for hepatic lesions was observed. Corresponding hepatic nodule incidence rates were 45.0, 40.0, 25.0 and 5.0% in positive control, low, middle and high groups, respectively (P < 0.01 or 0.05). Gross findings, histopathological and ultrastructural evaluations of hepatic lesion were performed on 9, 8, 5 and 1 hepatic nodule in positive control, low, middle and high doses of groups, respectively, identified in rats from the respective groups of 20. A decreasing trend of proportions of hepatocellular carcinoma masses accompanied the increasing doses of red raspberry extract. CONCLUSIONS: These findings demonstrate that the potent capacity of red raspberry diet could not only suppress DEN-induced hepatic lesions in rats, but also reduce the definite diagnostic features of neoplasm.

Cranberry phytochemical extract inhibits SGC-7901 cell growth and human tumor xenografts in Balb/c nu/nu mice.

Cranberry extract possesses potent antioxidant capacity and antiproliferative activity against cancer in vitro and in vivo. The objectives of this study were to determine whether the cranberry extract inhibited proliferation of human gastric cancer SGC-7901 cells and human gastric tumor xenografts in the Balb/c nu/nu mouse. Cranberry extract at doses of 0, 5, 10, 20, and 40 mg/mL significantly inhibited proliferation of SGC-7901 cells, and this suppression was partly attributed to decreased PCNA expression and apoptosis induction. In a human tumor xenograft model, the time of human gastric tumor xenografts in the mouse was delayed in a dose-dependent manner. A dose-response inhibition was also observed in the averages of size, weight, and volume of tumor xenografts in the mouse between the control and cranberry-treated groups. These results demonstrate fresh cranberries to be a chemopreventive reagent.