Evaluation of the expression of P-glycoprotein in propoxur-resistant Caco-2 cells.

UNLABELLED: There is a great concern about the effect of propoxur, as one of the more common N-methyl carbamate pesticides, on human health due to its extensive use in agricultural and non-agricultural applications. Caco-2 cells became resistant to propoxur, and the resistance was confirmed through MTT assay. Then the cell membrane integrity and P-glycoprotein expression were measured by LDH assay and western blot analysis, respectively and compared to the parent cells.  Contrary to what was expected, the expression of P-glycoprotein in propoxur resistant cells was lower than parent cells. CONCLUSION: This study indicates that the resistance to propoxur may not be related to P-glycoprotein expression directly, since P-glycoprotein expression has decreased in these cells.

Evaluation of anti-invasion effect of cannabinoids on human hepatocarcinoma cells.

CONTEXT: Cancer is a disease characterized by abnormal growth of cells. One of the most common types of liver cancers is called hepatocellular carcinoma (HCC) which is highly metastatic. As most of cannabinoids have shown anticancer effect against different cell lines in a number of reports, a biological investigation of two cannabinoids, CB65 (CB2 receptor agonist) and ACEA (CB1 receptor agonist) was carried out in this study. OBJECTIVE: In an attempt to find natural products as a new solution of cancer, this study was designed to investigate the potential antitumoral and anti-invasive activity of cannabinoids on HepG2 cells and the possible roles of matrix metalloproteinase-2 (MMP-2) and MMP-9 in its action. MATERIALS AND METHODS: The researchers examined the effect of various concentrations of CB65 (CB2 receptor agonist) and ACEA (CB1 receptor agonist), on the cell proliferation, viability, and invasion as well as expression of MMP-2 and MMP-9 in HepG2 cells using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT) assay, matrigel invasion assay, and western blotting method. RESULTS: The results revealed that both cannabinoids reduce cell viability, cell invasion as well as MMP-2 and MMP-9 expression in higher dose of 20 nM. Furthermore, higher concentrations of examined cannabinoids were more effective. DISCUSSION: These data suggest ACEA and CB65 as an option for novel treatment of hepatocellular cancer. CONCLUSION: Our findings may contribute to design of new therapeutic strategies for the management of HCC.