Measles virus as an oncolytic vector platform.

Viral vector systems are widely being used in the development of new genetic approaches for a variety of human diseases. Oncolytic viruses have shown great potential as cancer therapeutics. The ideal viral vector for cancer gene therapy eradicates a clinically significant fraction of malignant cells and leaves normal tissues unharmed. The Edmonston vaccine strain of measles virus is a replicating RNA virus which is characterized by its tumor selectivity and oncolysis. Its strong tumor suppressive potential combined with its excellent safety record as a viral vaccine makes it an optimal platform for oncolytic virotherapy of cancer. Recent advances in genetic engineering of measles virus allow insertion of therapeutic and diagnostic transgenes as well as complete retargeting of measles virus. These strategies resulted in the generation of recombinant measles viruses allowing non-invasive monitoring of viral replication and viral spread. The immune defense is a significant barrier for efficient viral gene therapy. Immune-evasive strategies have successfully been developed for measles virus enhancing its efficacy. This review gives an overview of measles virus as an anticancer agent; in particular, its use in oncologic virotherapy as well as new developments in targeting and immune evasive strategies.

[NASH -- nonalcoholic steatohepatitis]. / NASH -- nichtalkoholische Steatohepatitis.

Nonalcoholic steatohepatitis describes a hepatic disorder with the typical characteristics of an alcoholic pathogenesis without alcohol consumption. It was first described in 1962 and named NASH by Ludwig et al. 1980. Many researchers worked on this disease since this time. It represents the hepatic manifestation of the syndrome X. The pathogenesis is a two-hit phenomenon. The first hit leads to steatosis hepatis and makes the liver vulnerable to the second hit. Central factors of the second hit are oxygen-radicals, oxidative stress, lipid-peroxidation and cytokines. The exact pathogenic mechanisms are still unknown. NASH is a hepatic disease which can end up in liver cirrhosis and liver failure. Up to now a curative drug therapy does not exist. The poor prognosis in some cases, the increasing incidence in western populations and the lack of therapeutic options renders NASH to a serious problem. The aim of this article is to show the actual knowledge of this disease, especially focussed on the pathogenesis, by review of the literature from 1979 up to the present time.

Effective infection, apoptotic cell killing and gene transfer of human hepatoma cells but not primary hepatocytes by parvovirus H1 and derived vectors.

Autonomous parvoviruses preferentially replicate in and kill in vitro-transformed cells and reduce the incidence of spontaneous and implanted tumors in animals. Because of these natural oncotropic and oncolytic properties, parvoviruses deserve to be considered as potential antitumor vectors. Here, we assessed whether parvovirus H1 is able to kill human hepatoma cells by induction of apoptosis but spares primary human liver cells, and whether the former cells can efficiently be transduced by H1 virus-based vectors. Cell death, infectivity, and transgene transduction were investigated in Hep3B, HepG2, and Huh7 cells and in primary human hepatocytes with natural and recombinant H1 virus. All hepatoma cells were susceptible to H1 virus-induced cytolyis. Cell death correlated with H1 virus DNA replication, nonstructural protein expression, and with morphological features of apoptosis. H1 virus-induced apoptosis was more pronounced in p53-deleted Hep3B and p53-mutated Huh7 cells than in HepG2 cells which express wild-type p53. In Hep3B cells, apoptosis was partially inhibited by DEVD-CHO, a caspase-3 inhibitor. In contrast, H1 virus-infected primary hepatocytes were neither positive for nonstructural protein expression nor susceptible to H1 virus-induced killing. Infection with a recombinant parvovirus vector carrying the luciferase gene under control of parvovirus promoter P38 led to higher transgene activities in hepatoma cells than in the hepatocytes. Taken together, H1 virus kills human hepatoma cells at low virus multiplicity but not primary hepatocytes. Thus, recombinant H1 viruses carrying antitumor transgenes may be considered as potential therapeutic options for the treatment of hepatocellular carcinomas.