Locoregional immunochemotherapy in hepatocellular carcinoma

Hepatocellular carcinoma remains a disease with a poor and dismal prognosis, and all forms of currently available conventional therapies are rarely beneficial. However, in recent years, combined targeting locoregional immunochemotherapy has been reported with very promising results. Adoptive immunotherapy with LAK cells (lymphokine-activated killer cells) and recombinant interleukin-2 is becoming one of the new modalities to reconstitute the depressed immune status of the tumor-bearing host. Interleukin-2, gamma-interferon, and interleukin-12 induce cytolytic activity of LAK and natural killer cells and are considered for cellular activation to locoregional immunotherapy before, after resection or even in unresectable hepatocellular carcinomas. Spleen is a suitable organ for LAK cell induction because it has densely packed lymphocytes. The strategy of administration of both interleukin-2 and gamma-interferon into the spleen for in vivo immunostimulation is based on the well-known synergism of the above cytokines. LAK cells have cytotoxic activity against a variety of tumor cells. In particular, LAK cells exhibit efficacy against lung and liver malignant lesions, as suggested by their trafficking pattern; activated killer cells injected i.v. into humans appeared in the lung early and were subsequently rapidly redistributed to the liver and spleen. Lipiodol-Urografin emulsion is probably an ideal cytokine/anti-cancer drug carrier suitable for the combined locoregional immunochemotherapy because during its preferential retention in the vascular network of the spleen and tumor, a gradual release of both immuno- and chemotherapeutical drugs bound to emulsion droplets is achieved ensuring a prolong half life for these drugs. Recent data point to the potential of considering intratumoral or intravascular use of adenovirus carrying interleukin-12 gene, and/or p53-based gene therapy as possible therapeutic strategies in patients with hepatocellular carcinoma.