Transduction of antisense cyclin D1 using two-step gene transfer inhibits the growth of rat hepatoma cells.

Cyclin D1, one of the G(1) cyclins, is frequently overexpressed in several types of carcinomas and is thought to play an important role in tumorigenesis and tumor progression including hepatocellular carcinoma. We constructed a retrovirus vector-carrying rat cyclin D1 cDNA in the reverse orientation, resulting in expression of antisense (AS) cyclin D1 mRNA. For efficient transduction of this recombinant retrovirus, two-step gene transfer was performed. The rat hepatoma cell line (dRLh84) was infected with this recombinant retrovirus after preinfection with adenovirus expressing the retrovirus receptor. In the rat hepatoma cells, AS cyclin D1 mRNA was expressed, inducing a decrease in the expression of endogenous cyclin D1 mRNA and an inhibition of cell growth. Moreover, two-step gene transfer of AS cyclin D1 into s.c. hepatoma xenografts resulted in inhibition of tumor growth and prolonged animal survival. In the virus-infected tumor xenografts, expression of cyclin D1 was immunohistochemically inhibited, and apoptosis of hepatoma cells was detected. These findings suggest that transduction of AS cyclin D1 is useful as an adjunct to standard treatments for hepatocellular carcinoma.

Gene therapy targeting for hepatocellular carcinoma: selective and enhanced suicide gene expression regulated by a hypoxia-inducible enhancer linked to a human alpha-fetoprotein promoter.

We previously reported that the retroviral vector expressing the herpes simplex virus-thymidine kinase gene under the control of 0.3-kb human alpha-fetoprotein (AFP) gene promoter (AF0.3) provided the cytotoxicity to ganciclovir (GCV) in high-AFP-producing human hepatoma cells but not in low-AFP-producing cells. Therefore, specific enhancement of AFP promoter activity is likely to be required to induce enough cytotoxicity in low-AFP-producing hepatoma cells. In this study, we constructed a hybrid promoter, [HRE]AF, in which a 0.4-kb fragment of human vascular endothelial growth factor 5'-flanking sequences containing hypoxia-responsive element (HRE) was fused to AF0.3 promoter. By means of the reporter gene transfection assay, hypoxia-inducible transcriptions that were mediated by [HRE]AF promoter were detected in low- and non-AFP-producing human hepatoma cells, but not in nonhepatoma cells. When the herpes simplex virus-thymidine kinase gene controlled by [HRE]AF promoter was transduced into hepatoma and nonhepatoma cells by a retroviral vector, the exposure to 1% O2 induced GCV cytotoxicity specifically in the hepatoma cells. Moreover, in nude mice bearing solid tumor xenografts, only the tumors consisting of the virus-infected hepatoma cells gradually disappeared by GCV administration. These results indicate that the hypoxia-inducible enhancer of the human vascular endothelial growth factor gene, which is directly linked to human AFP promoter, involves selective and enhanced tumoricidal activity in gene therapy for hepatocellular carcinoma.

A case of acute hepatitis A with marked hemophagocytosis in bone marrow.

A previously well 18-year-old female was referred to our hospital because of abnormalities of blood biochemistry and slight jaundice. Because serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels were elevated more than 6000 IU/L, the patient was suspected to have acute viral hepatitis. The platelet count on admission was 9.7x10(4)/µl, which was decreased from the initial value of 21x10(4)/µl for 3 days. The coagulation tests revealed marked elevation of D-dimmer, fibrinogen degradation products and thrombin-antithrombin III complex suggesting increase in fibrinolysis. Serum levels of high density lipoprotein cholesterol and ferritin were markedly decreased and increased, respectively. The bone marrow smears revealed proliferation of mature histiocytes ingesting platelets and erythrocytes, these pathological findings were consistent with those of hemophagocytic syndrome (HPS). In addition, anti-hepatitis A IgM antibody in the serum and hepatitis A virus (HAV) RNA in the stool were positive. Therefore, the patient was diagnosed as having acute hepatitis A with probable HPS. Since a fulminant clinical course was suspected, glucocorticoid pulse therapy was started immediately 7 days after onset and a favorable clinical outcome resulted.

Transduction of Escherichia coli by bacteriophage P1 in soil.

Transduction of Escherichia coli W3110(R702) and J53(RP4) (10(4) to 10(5) CFU/g of soil) by lysates of temperature-sensitive specialized transducing derivatives of bacteriophage P1 (10(4) to 10(5) PFU/g of soil) (P1 Cm cts, containing the resistance gene for chloramphenicol, or P1 Cm cts::Tn501, containing the resistance genes for chloramphenicol and mercury [Hg]) occurred in soil amended with montmorillonite or kaolinite and adjusted to a -33-kPa water tension. In nonsterile soil, survival of introduced E. coli and the numbers of E. coli transductants resistant to chloramphenicol or Hg were independent of the clay amendment. The numbers of added E. coli increased more when bacteria were added in Luria broth amended with Ca and Mg (LCB) than when they were added in saline, and E. coli transductants were approximately 1 order of magnitude higher in LCB; however, the same proportion of E. coli was transduced with both types of inoculum. In sterile soil, total and transduced E. coli and P1 increased by 3 to 4 logs, which was followed by a plateau when they were inoculated in LCB and a gradual decrease when they were inoculated in saline. Transduction appeared to occur primarily in the first few days after addition of P1 to soil. The transfer of Hg or chloramphenicol resistance from lysogenic to nonlysogenic E. coli by phage P1 occurred in both sterile and nonsterile soils. On the basis of heat-induced lysis and phenotype, as well as hybridization with a DNA probe in some studies, the transductants appeared to be the E. coli that was added. Transduction of indigenous soil bacteria was not unequivocally demonstrated.(ABSTRACT TRUNCATED AT 250 WORDS)

An erythrocyte membrane antigen associated with X-linked muscular dystrophy.

Goat antiserum was prepared against erythrocyte membranes obtained from a man who had X-linked muscular dystrophy. When cross-adsorbed with control membranes and tested on double immunodiffusion plates or by binding to intact erythrocytes suspended in thin-layer agar plates, this antiserum discriminated between membranes from phenotypically normal controls and dystrophic men, and between controls and obligate female dystrophy carriers. It also identified two populations among a small sample of women at risk for being dystrophy carriers.