[Secretory expression vector V-pLNCX-s-hri inhibits the growth of mouse B16 melanoma].

Background And Objective: Human ribonuclease inhibitor (hRI) extracted and purified from human placenta has been shown to remarkably inhibit some solid tumors in mice. This study was to construct V-pLNCX-s-hri, a secretory expression vector, and explore its inhibition effects on the growth of mouse B16 melanoma cells.

Methods: The hRI gene sequence conjugated with the synthesized signal peptide of mouse IgG was cloned into the retroviral vector V-pLNCX to construct V-pLNCX-s-hri.

[Transfection and expression of hRI gene on human umbilical blood stem cells and gene therapy for mouse melanoma].

In order to explore the transfection and expression of hRI gene on human umbilical blood stem cells, and observe it's effect on the tumor growth. After enriching human umbilical cord blood CD34+ cells with a high-gradient magnetic cell sorting system (MACS), transfected them with supernatant of retrovirus containing human Ribonuclease inhibitor (hRI) cDNA. Hematopoietic progenitor clonogenic assay and PCR were used to evaluate transfection efficiency, and Western-blot and immune fluorescence were used to evaluate the expression quantity of hRI gene after transfection.

[Anti-oxidative effect of ribonuclease inhibitor by site-directed mutagenesis and expression in Pichia pastoris].

Human placental ribonuclease inhibitor is an acidic protein of Mr approximately 50 kDa with unusually high contents of leucine and cysteine. It is a cytosolic protein that protects cells from the adventitious invasion of pancreatic-type ribonuclease. HRI has 32 cysteine residues, and the oxidative formation of disulfide bonds from those cysteine residues is a rapid cooperative process that inactivates HRI.

Antitumor effects of human ribonuclease inhibitor gene transfected on B16 melanoma cells.

Human ribonuclease inhibitor (RI) is a cytoplasmic acidic protein. The experiment demonstrated that it might effectively inhibit tumor-induced angiogenesis and inhibit tumor growth. Ribonuclease inhibitor is constructed almost entirely of leucine-rich repeats, which might be involved in unknown biological effects besides inhibiting RNase A and angiogenin activities.

[Inhibitory effect of ginsenoside-Rg3 on lung metastasis of mouse melanoma transfected with ribonuclease inhibitor].

Objective: To investigate the effect of ginsenoside-Rg3 on lung metastasis of ribonuclease inhibitor (RI) gene-transfected mouse B16 melanoma.

Methods: C57BL/6 mice were iv injected with parental or RI-transfected B16 melanoma cells. Lung metastasis was assessed by the number of surface tumor nodules.

Effects of DNA methylation inhibitor on down-regulation of ribonuclease inhibitor expression in cancer cell lines.

Background & Objective: Human ribonuclease inhibitor (RI) could effectively block angiogenin-induced angiogenesis, and inhibit growth of transplant solid tumors in animals. However, its exact molecular mechanism of antitumor has not been totally ascertained. Many tumor suppressor genes occur loss of expression by aberrant methylation in promoter region.

[Preparation and purification of the antibody against ribonuclease inhibitor].

Aim: To prepare and purify the antibody against ribonuclease inhibitor(RI).

Methods: RI was extracted from human placenta and purified by affinity chromatography. Rabbits anti-RI antibody was obtained after immunization and then purified through rProtein A Sepharose Fast Flow chromatography column.

[Analysis of gene expression of ribonuclease inhibitor in human breast cancer tissue].

Background & Objective: Ribonuclease inhibitor (RI), which is rich in human placenta, is a multi-functional acidic glycoprotein. Our previous studies showed that the growth of some solid tumors (S180 sarcoma, Ca761 breast cancer, and H22 hepatoma) could be significantly inhibited by RI extracted and purified from human placenta. This study was designed to observe the change of RI gene expression in human breast cancer tissue.

The antioxidant effects of ribonuclease inhibitor.

Ribonuclease inhibitor (RI) is an acidic cytosolic glycoprotein with molecular weight of about 50 kDa, which contains 32 cysteine residues. It is possibly that RI may have antioxidant effect by thiol-disulfide exchange reaction. We studied the effects of RI over-expression on the rat glial cell line C6 injured with H2O2.