myelin-basic-protein and Liver-Neoplasms

To test the effects of the 21.5 kDa human brain myelin basic protein (MBP) on the proliferation and apoptosis of HepG-2.. pSVCEP-MBP-CAT plasmid containing the full-length 21.5 kDa MBP cDNA was transfected into human hepatoma carcinoma cells (HepG-2). The pSVCEP-CAT vector transfected HepG-2 cells served as negative control. RT-PCR and Western blot were performed to confirm the effectiveness of the transfection. MTT measures were used to determine the proliferative curve of cells. H2O2 was then added to induce cell apoptosis. DNA ladder, immunohistochemistry assay, comet electrophoresis and TUNEL (Terminal Deoxynucleotidyl Transferase Biotin-dUTP Nick End Labeling) were used to detect the apoptosis and relevant protein expressions.. The 21.5 KDa MBP cDNA was transfected into HepG-2 cells successfully. MTT measures of pSVCEP-MBP-CAT transfected group showed increased proliferation and anti-apoptosis. The control group displayed with more typical DNA ladders and much higher level of Caspase-3 than the MBP group. Comet and TUNEL assays revealed that the control group cells had significant DNA damages and serious apoptosis, whereas the MBP group showed slight changes.. The 21.5 kDa MBP promotes the proliferation of HepG-2 and blocks apoptosis.

Topics: Apoptosis; Carcinoma, Hepatocellular; Cell Proliferation; Hep G2 Cells; Humans; Liver Neoplasms; Myelin Basic Protein; Nerve Tissue Proteins; Transcription Factors; Transfection

Spleen-cell sensitivity to encephalitogenic factor (EF) was measured with the macrophage migration inhibition (MMI) test over a period of time in hamsters inoculated with SV40-transformed tumour cells and in rats treated with 4-dimethylamino-3'-methylazobenzene.Spleen cells from hamsters receiving 10 or 10(3) SV40 tumour cells gave inhibition of macrophage migration with EF at a significance level of P<0·05 21 days after implantation. Spleen cells from animals receiving 10(5) tumour cells gave inhibition at a significance level of P<0·001 after the same interval.Spleen-cell sensitivity to EF, and the abrogation of this sensitivity by serum, was investigated over a period of time in rats undergoing hepatocarcinogenesis. Sensitivity to EF was seen in 2/10 animals (20%) with minimal lesions of the liver, in 2/16 animals (12%) with proliferative changes and/or cholangiofibrosis, in 7/15 animals (46%) with dysplastic lesions of portal-tract epithelial cells and in all 5 animals with cholangiocarcinoma. None of a control group of 10 animals showed any response to EF. Autologous serum abrogated the spleen-cell response to EF in one sensitized animal with proliferative changes and cholangiofibrosis, in all 7 sensitized animals with dysplastic hepatic lesions and in 4/5 sensitized animals with cholangiocarcinoma. Autologous serum had no effect on macrophage migration in the 10 control animals.These findings indicate that a progressive increase in sensitization to EF occurs during carcinogenesis and is evident at the point of preneoplastic dysplasia. This has an obviously important bearing on the clinical use of such tests.

Topics: Animals; Cell Migration Inhibition; Cell Transformation, Viral; Hypersensitivity, Delayed; Immunity, Cellular; Liver Neoplasms; Macrophages; Myelin Basic Protein; Neoplasms, Experimental; Rats; Spleen; Time Factors