[Show abstract][Hide abstract] ABSTRACT: To observe the effects of lead on mRNA and protein expression of PKC in U251 cell line.
After U251 cells were exposed to 0.05, 0.50, 5.00, 50.00, 500.00, 900.00 and 1000.00 micromol/L Ph(Ac)2 for 24 hours, the cytotoxicity of Pb on U251 cells was measured by MTT assay. RT-PCR and Western blot assay were used to detect the mRNA and protein expression levels of PKC in U251 cells exposed to 0.05, 5.00 and 500.00 micromol/L Ph (Ac), for 24 hours.
The survival rates of U251 cells treated with 5.00, 50.00, 500.00, 900.00 and 1000.00 micromol/L Pb (Ac)2 were 84.5%, 78.2%, 76.5%, 50.3% and 43.2%, respectively, which were significantly lower than those of control group (P < 0.01). The PKC mRNA expression level (0.40 +/- 0.01) of U251 cells treated with 500.00 micromol/L Pb (Ac)2 was significantly lower than that (0.51 +/- 0.02) of control group (P < 0.01). The PKC protein expression levels of U251 cells treated with 0.05, 5.00 or 500.00 micromol/L Pb(Ac)2 were 0.68 +/- 0.02, 0.62 +/- 0.01 and 0.33 +/- 0.02, respectively, which were significantly lower (0.98 +/- 0.01) than those of control group (P < 0.01).
Lead can decline the cell viability, PKC mRNA and protein expression levels of U251 cells.
No preview · Article · Feb 2012 · Zhonghua lao dong wei sheng zhi ye bing za zhi = Zhonghua laodong weisheng zhiyebing zazhi = Chinese journal of industrial hygiene and occupational diseases
[Show abstract][Hide abstract] ABSTRACT: Tocotrienol is considered a beneficial effect agent on inhibition of tumor development. In this study, we focused on the effects of δ-tocotrienol and its possible mechanism on induction of death in human colon cancer SW620 cells. δ-Tocotrienol inhibited proliferation of SW620 cell in a dose-dependent manner. Our findings showed that δ-tocotrienol effectively induced paraptosis-like death in SW620 cells, correlated with the vacuolation that may be from welling and fusion of mitochondria and/or the endoplasmic reticulum (ER) as well as caspase-3 nonactivated. However, there were no changes in apoptosis based on flow cytometry analysis. Of being noted, δ-tocotrienol reduced the expression of β-catenin and wnt-1 proteins by about 50% at the highest dose (20μmol/L). δ-Tocotrienol also decreased cyclin D1, c-jun and MMP-7 protein levels in SW620 cells. Altogether, these data indicate that δ-tocotrienol induces paraptosis-like cell death, which is associated with the suppression of the Wnt signaling pathway. Thus, our findings may provide a novel application in treatment of human colon carcinoma.