The present invention derives from the finding that increased levels of Toll related receptor 9 (TLR9) and Toll related receptor 7 (TLR7) are associated with liver cancer and in particular hepatocellular carcinoma. Accordingly, the invention provides TLR9 and TLR7 antagonists for use in a method of treating liver cancer. The invention provides other strategies such as modulation of endosomal signalling by using compounds such as chloroquine to prevent or treat such liver cancer. The invention also provides agents capable of inducing an immune response against TLR9 and TLR7 for use in a method of treating liver cancer. The presence of TLR9 and TLR7 expression may be indicative of the presence of liver cancer and the amount of TLR9 and TLR7 expression may be indicative of the rate of growth or spreading of the cancer.