Prognostic and Therapeutic Implications of Microvascular Invasion in Hepatocellular Carcinoma

Epithelial-mesenchymal transitions (EMT) are vital for morphogenesis during embryonic development and are also implicated in the conversion of early stage tumors into invasive malignancies. Several key inducers of EMT are transcription factors that repress E-cadherin expression. A recent report in Cell (Yang et al., 2004) adds Twist to this list and links EMT to the ability of breast cancer cells to enter the circulation and seed metastases.

We sought to determine the factors associated with survival after recurrence of hepatocellular cancer (HCC) after resection and the outcome of our prospectively applied treatment protocol.

Hepatocellular carcinoma (HCC) is an aggressive malignancy mainly due to metastases or postsurgical recurrence. We postulate that metastases are influenced by the liver microenvironment. Here, we show that a unique inflammation/immune response-related signature is associated with noncancerous hepatic tissues from metastatic HCC patients. This signature is principally different from that of the tumor. A global Th1/Th2-like cytokine shift in the venous metastasis-associated liver microenvironment coincides with elevated expression of macrophage colony-stimulating factor (CSF1). Moreover, a refined 17 gene signature was validated as a superior predictor of HCC venous metastases in an independent cohort, when compared to other clinical prognostic parameters. We suggest that a predominant humoral cytokine profile occurs in the metastatic liver milieu and that a shift toward anti-inflammatory/immune-suppressive responses may promote HCC metastases.