Microenvironment influence on human colon adenocarcinoma phenotypes and matrix metalloproteinase-2, p53 and ß-catenin tumor expressions from identical monoclonal cell tumor in the orthotopic model in athymic nude rats.

The present study aims to identify differences between left and right colon adenocarcinoma arising from identical clonal cell and to find out if microenvironment has any influence on matrix metalloproteinase-2 (MMP2), p53 and ß-catenin tumor expressions. MATERIAL AND METHODS. Rats (RNU) were submitted to cecostomy to obtain the orthotopic model of right colon tumor (n = 10), while for the left colon model (n = 10), a colon diversion and distal mucous fistula in the descending colon was used. Cultivated human colon adenocarcinoma cells (WiDr) were inoculated in stomas submucosa. Histopathological analysis, real-time reverse transcription-PCR for ß-catenin, p53 and MMP2, as well as immunohistochemical analysis for p53 and ß-catenin expression were conducted. Central tendency, variance analysis and the Livak delta-delta-CT method were used for statistical analysis, adopting a 5% significance level. RESULTS. All tumors from the left colon exhibited infiltrative ulceration, while in the right colon tumor growth was predominantly exophytic (67%). In the left colon, tumor growth was undifferentiated (100%), while it was moderately differentiated in the right colon (83%). In right colon tumors, MMP2, p53, and ß-catenin gene expressions were higher than compared to left colon (p = 4.59354E-05, p = 0.0035179, p = 0.00093798, respectively, for MMP2, p53 and ß-catenin). ß-catenin and p53 results obtained by real-time polymerase chain reaction were confirmed by immunohistochemistry assay (p = 0.01 and p = 0.001, respectively, for ß-catenin and p53). CONCLUSION. Left and right human colon adenocarcinomas developed in animal models have distinct phenotypes even when they have the same clonal origin. Microenvironment has influenced p53, ß-catenin, and MMP2 expression in animal models of colon cancer.

Effects of Adper™ Scotchbond™ 1 XT, Clearfil™ SE Bond 2 and Scotchbond™ Universal in Odontoblasts.

This study aimed to assess the cytotoxicity of commercially available adhesive strategies-etch-and-rinse (Adper™ Scotchbond™ 1 XT, 3M ESPE, St. Paul, MN, USA, SB1), self-etch (Clearfil™ SE Bond 2, Kuraray Noritake Dental Inc., Tokyo, Japan, CSE), and universal (Scotchbond™ Universal, 3M Deutschland GmbH, Neuss, Germany, SBU). MDPC-23 cells were exposed to adhesives extracts in different concentrations and exposure times. To access cell metabolic activity, viability, types of cell death, and cell cycle, the MTT assay, SRB assay, double labeling with annexin V and propidium iodide, and labeling with propidium iodide/RNAse were performed, respectively. Cultures were stained with May-Grünwald Giemsa for qualitative cytotoxicity assessment. The SB1, CSE, and SBU extracts determined a significant reduction in cell metabolism and viability. This reduction was higher for prolonged exposures, even for less concentrated extracts. CSE extracts significantly reduced the cell's metabolic activity at higher concentrations (50% and 100%) from 2 h of exposure. After 24 and 96 h, a metabolic activity reduction was verified for all adhesives, even at lower concentrations. These changes were dependent on the adhesive, its concentration, and the incubation time. Regarding cell viability, SBU extracts were the least cytotoxic, and CSE was significantly more cytotoxic than SB1 and SBU. The adhesives determined a reduction in viable cells and an increase in apoptotic, late apoptosis/necrosis, and necrotic cells. Moreover, on cultures exposed to SB1 and CSE extracts, a decrease in the cells in S and G2/M phases and an increase in the cells in G0/G1 phase was observed. Exposure to SBU led to an increase of cells in the S phase. In general, all adhesives determined cytotoxicity. CSE extracts were the most cytotoxic and were classified as having a higher degree of reactivity, leading to more significant inhibition of cell growth and destruction of the cell's layers.

Development of an analytical methodology for simultaneous determination of vincristine and doxorubicin in pharmaceutical preparations for oncology by HPLC-UV.

A high-performance liquid chromatography-UV methodology (lambda=230 nm) was developed and validated for the simultaneous determination of vincristine and doxorubicin in pharmaceutical preparations used in oncology. The chromatography was carried out on a C18 column using acetonitrile 90% in water-potassium hydrogenphosphate buffer 50 mM, pH 3.2+/-0.1 (32:68, v/v) as mobile phase at a flow rate of 1.5 mL/min. The method proved to be specific, exact, and accurate, in accordance with the ICH standards, presenting linearity in the 1-5 microg/mL and 5-100 microg/mL intervals, and detection (0.19x0.51 microg/mL) and quantification (0.63x1.7 microg/mL) limits for vincristine and doxorubicin, respectively.

[The impact of selective clamping of portal vein in hepatocellular function. An experimental study]. / Estudo experimental do impacto da clampagem selectiva da veia porta na função hepatocelular.

UNLABELLED: The influence of selective clamping of the elements of hepatic pedicle in the hepatocellular function and viability were evaluated in our department. AIM: Study the effect of selective clamping of the portal vein (CPV) in hepatocellular function in an animal model with normal liver. METHOD: Three groups of Wistar rats (males, 2 months) were subjected a CPV for 60 min: group A (n=21) submitted to a continuous inflow occlusion; group B (n=12) underwent to a CPV for 30 min with 5 min of reperfusion; group C (n=10) underwent a CPV for 15 min with 5 min of reperfusion. The group D (n=9) was not subjected to a CPV. A hepatic biopsy was done at the end of surgery. The degree of tissue injury was evaluated using: 1) blood markers: AST, ALT, total bilirubin (TB), GGT alkaline-phosphatase, LDH and hepatic extraction fraction (HEF) by radioisotopic methods three days before laparotomy (BS) and after surgery (AS); 2) apoptosis, necrosis were investigated after collagenase cell isolation from hepatectomy pieces by flow-cytometry using the followed probes: propidium-iodide and annexin-V. STATISTICAL ANALYSIS: variance analysis, post-hoc comparisons by Turkey-test (p<0.05). RESULTS: 1) Mortality: Group A - 62%, Group B - 17%, Group C - 30%, Group D - 0% (p<0.03). 2) We observed statistical differences in these parameters: ALT (p<0,025) and LDH (p<0,002) preferentially in groups A but without differences between the A,B,C and D Groups (ns). 3) We also verified a significant decrease in HEF values (p<0,0001) preferentially in group A without differences between the groups. 4) No difference were observed when analysed apoptosis and necrosis and cell viability between the groups. CONCLUSIONS: Postoperative liver failure is the leading cause of mortality after hepatectomy, however selective clamping of the portal vein, is reflected in an increase in cell viability and a decrease in the type of cell death (necrosis ou apoptosis) compared to studies carried out previously by us and thus may be regarded as an alternative to the Pringle maneuver. However, selective clamping of the portal vein for periods above 30' should be avoided, given the high mortality verified.

[Granzymes A and B in pulmonary sarcoidosis (experimental study)].

Sarcoidosis is a systemic disease of unknown aetiology, morphologically characterized by well-formed epithelioid granulomas, which show little or no central necrosis. These may be present in any organ or tissue. The lung is the most frequently and prominently involved target. The granuloma is often very sharply demarcated from the adjacent tissue and is surrounded by a mantle of lymphocytes, which mediate lysis of target cells by various mechanisms, including exocytosis of lytic proteins, perforins and granzymes. Sarcoidosis laboratorial diagnosis is usually made by SACE and Lisozyme dosages. The granzymes A and B could be two other markers of the disease, since the sarcoidosis granuloma is rich in cytotoxic and NK cells. An ELISA Kit was used to measure Granzyme A and B in serum of a normal control group (NC) (n=30), and in two groups with lung pathology: one without sarcoidosis, disease control (DC) (n=21) and other with sarcoidosis (S) (n=11). Our results showed that SACE activity is significantly augmented in S group comparing with NC and DC, respectively: 82,6+/-32,7/31,9+/-17,8 - p=0,00017 and 82,6+/-32,7/31,9+/-17,8 - p=0,00024. Lisozyme activity is significantly augmented in S and DC groups comparing with NC. Granzyme B showed a significant decrease in DC and S groups comparing with NC. Granzyme A showed a significant decrease between S/NC groups. Our results suggest that the decrease of Granzyme A and B in sarcoidotic patients could be related to an ineffective inflammatory local response related to the formation of sarcoidosis granulomas. More studies are needed, particularly in BAL.

Effects of X-radiation on lung cancer cells: the interplay between oxidative stress and P53 levels.

Lung cancer (LC) ranks as the most prevalent and deadliest cause of cancer death worldwide. Treatment options include surgery, chemotherapy and/or radiotherapy, depending on LC staging, without specific highlight. The aim was to evaluate the effects of X-radiation in three LC cell lines. H69, A549 and H1299 cell lines were cultured and irradiated with 0.5-60 Gy of X-radiation. Cell survival was evaluated by clonogenic assay. Cell death and the role of reactive oxygen species, mitochondrial membrane potential, BAX, BCL-2 and cell cycle were analyzed by flow cytometry. Total and phosphorylated P53 were assessed by western blotting. Ionizing radiation decreases cell proliferation and viability in a dose-, time- and cell line-dependent manner, inducing cell death preferentially by apoptosis with cell cycle arrest. These results may be related to differences in P53 expression and oxidative stress response. The results obtained indicate that sensibility and/or resistance to radiation may be dependent on molecular LC characteristics which could influence response to radiotherapy and treatment success.