Angiogenesis: the Yin and Yang in intrahepatic cholangiocarcinoma

The tumor microenvironment (TME) constitutes a complex structure comprising different cell types and soluble factors that surround the tumor and promote its progression. Primarily for its pivotal role in malignant growth, TME has become a potential therapeutic objective for developing new targeted therapy and a marker for assessing therapeutic response. In intrahepatic cholangiocarcinoma (iCCA), the second most common primary liver malignancy, TME has also gained a central role in understanding the mechanisms underlying tumor progression. In this review, we focused on the role of angiogenic factors and their pathway in iCCA and analyzed possible therapeutic and prognostic implications.