viernes, 11 de abril de 2014

Nuevas esperanzas de combatir el cáncer de hígado con inmunoterapia (linfocitos T)

Immunotherapy could help tackle tough liver cancer

London, England, Friday 11 April 2014 Significant new data presented today at the International Liver Congres 2014 indicate that liver cancer (Hepatocellular Carcinoma (HCC)) may be treated by adoptive T-cell therapy. This new therapeutic approach in the treatment of HCC could be very important as without treatment the 5 year survival rate is just 5%. Globally, HCC accounts for 746,000 deaths, and in the UK alone is responsible for over 4,000 deaths per year.

Glypican-3 (GPC3) is a tumour associated antigen expressed in up to 70% of HCC but not in healthy human tissue. Isolating GPC3-specific T-cell receptors and expressing them on patient's T-cells can help treat HCC, as these T cells can recognise and eliminate GPC3-postive HCC.

The study detected and expanded MHC-multimer-positive CD8+ T-cells specific for targeted GPC3 epitopes and grew T-cell clones. From these clones, the most specific and active T-cell receptor was isolated. When this T-cell receptor was expressed on donor T cells it conferred specificity for GPC3, the HCC-associated antigen. Thus, it enables HLA-A2+ patient's T cells to specifically kill GPC3+ HCC.

Systemic treatments for advanced stage HCC are constantly evolving and current approaches include drug treatment with sorafenib - yet the current standard of care still does not offer a strong enough prognosis for patients. Liver transplant is an option for only 10 -15% of HCC carriers diagnosed at an early stage and therefore the importance of other treatment options for patients is critical. This is a treatment gap that adoptive T-cell therapy could potentially fill.