Priming of hepatitis C virus-specific cytotoxic T lymphocytes in mice following portal vein injection of a liver-specific plasmid DNA

Cytokine gene transfer for cancer therapy

The possibility of inducing a strong immune response to impair tumor growth by ectopically expressing cytokines, followed by the generation of an antitumor memory raised great hopes and enthusiasm as a therapeutic approach. However, the efficacy of this strategy on established tumor models appeared low and the initial results in the clinics were disappointing. Recently, new evidence indicates that cytokine gene combination or the combined use of cytokine genes with additional gene therapy approaches induces a synergistic effect supporting the use of cytokine gene therapy to improve the clinical outcome for cancer patients.

Hepatocellular carcinoma: therapy and prevention

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide. The major etiologies and risk factors for the development of HCC are well defined and some of the multiple steps involved in hepatocarcinogenesis have been elucidated in recent years. Despite these scientific advances and the implementation of measures for the early detection of HCC in patients at risk, patient survival has not improved during the last three decades. This is due to the advanced stage of the disease at the time of clinical presentation and limited therapeutic options. The therapeutic options fall into five main categories: surgical interventions including tumor resection and liver transplantation, percutaneous interventions including ethanol injection and radiofrequency thermal ablation, transarterial interventions including embolization and chemoembolization, radiation therapy and drugs as well as gene and immune therapies. These therapeutic strategies have been evaluated in part in randomized controlled clinical trials that are the basis for therapeutic recommendations. Though surgery, percutaneous and transarterial interventions are effective in patients with limited disease (1-3 lesions, <5 cm in diameter) and compensated underlying liver disease (cirrhosis Child A), at the time of diagnosis more than 80% patients present with multicentric HCC and advanced liver disease or comorbidities that restrict the therapeutic measures to best supportive care. In order to reduce the morbidity and mortality of HCC, early diagnosis and the development of novel systemic therapies for advanced disease, including drugs, gene and immune therapies as well as primary HCC prevention are of paramount importance. Furthermore, secondary HCC prevention after successful therapeutic interventions needs to be improved in order to make an impact on the survival of patients with HCC. New technologies, including gene expression profiling and proteomic analyses, should allow to further elucidate the molecular events underlying HCC development and to identify novel diagnostic markers as well as therapeutic and preventive targets.

Treatment of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignant tumours worldwide. The major etiologies and risk factors for HCC development are well defined and some of the multiple steps involved in hepatocarcinogenesis have been elucidated in recent years. Despite these scientific advances and the implementation of measures for early HCC detection in patients at risk, patient survival has not improved during the last three decades. This is due in part to the advanced stage of the disease at the time of clinical presentation, in part due to the limited therapeutic options. These fall into four main categories: (1) surgical interventions, including tumour resection and liver transplantation, (2) percutaneous interventions, including ethanol injection and radiofrequency thermal ablation, (3) transarterial interventions, including embolisation and chemoembolisation and (4) drugs as well as gene and immune therapies. These therapeutic strategies have been evaluated in part in randomised controlled clinical trials that are the basis for therapeutic recommendations. While surgery and percutaneous as well as transarterial interventions are effective in patients with limited disease (1-3 lesions, < 5 cm in diameter) and compensated underlying liver disease (cirrhosis Child A), at the time of diagnosis more than 80% patients present with multicentric HCC and advanced liver disease or comorbidities that restrict the therapeutic measures to best supportive care. In order to reduce morbidity and mortality from HCC, therefore, early diagnosis and the development of novel systemic therapies for advanced disease, including drugs, gene and immune therapies as well as primary HCC prevention are of paramount importance. Further, secondary HCC prevention after successful therapeutic interventions needs to be improved in order to make an impact on the survival of patients with HCC. New technologies, including gene expression profiling and proteomic analyses, should further elucidate the molecular events underlying HCC development and identify novel diagnostic markers as well as therapeutic and preventive targets.

Recently primed CD8+ T cells entering the liver induce hepatocytes to interact with naïve CD8+ T cells in the mouse

Large number of T cells traffic through the liver. In order to examine the effects of such traffic on the phenotype of hepatocytes, we vaccinated mice using DNA vaccines encoding antigens with MHC class I-binding epitopes. Small numbers of activated CD8(+) T blasts (10(5)-10(6)/liver) changed the surface phenotype and cytokine expression profile of hepatocytes (HCs). HCs upregulate surface expression of major histocompatibility complex (MHC) class I molecules and CD1d but not MHC class II molecules Qa-1, CD80, CD86, CD54, or CD95; in addition, they expressed/secreted interleukin (IL)-10 and IL-4 but not IL-1, IL-6, IL-13, interferon (IFN)-gamma, tumor necrosis factor (TNF), IL-4, or IL-27 (i.e., they acquire the HC* phenotype). HCs* (but not HCs) induced specific activation, proliferation, and IFN-gamma, TNF, and IL-13 release of cocultured naïve CD8(+) T cells. In contrast to the specific activation of naïve CD8(+) T cells by dendritic cells (DCs), specific CD8(+) T cell activation by HC* was not down-modulated by IFN-alphabeta. Only recently activated CD8(+) T blasts (but not recently activated CD4(+) T blasts or activated cells of the innate immune system, including natural killer T [NKT] cells) induced the HC* phenotype that is prominent from day 10 to day 20 postvaccination (i.e., time points at which peak numbers of recently primed CD8(+) T blasts are found in the liver). In conclusion, recently activated CD8(+) T blasts that enter the liver postimmunization in small numbers can transiently modulate the phenotype of HC, allowing them to activate naïve CD8(+) T cells with unrelated specificities.