Antitumor Activity of Isosteroidal Alkaloids from the Plants in the Genus Veratrum and Fritillaria

Isosteroidal alkaloids are a category of promising bioactive compounds which mostly exist in plants of genus Veratrum and Fritillaria. The pharmacological activities of isosteroidal alkaloids include antihypertensive, antitussive, anti-inflammatory, antithrombosis, among others. Recently, some studies show that this kind of alkaloids exhibited significant antitumor activity. To the best of our knowledge, there is no review focusing on their antitumor activity and mechanism of their antitumor activity. To fill the gap, in this review, we summarized antitumor effects of the isosteroidal alkaloids from genus Veratrum and Fritillaria on different tumors and the mechanisms of their antitumor activity. In conclusion, this kind of alkaloids has extensive antitumor activity, and there are several main mechanisms of their antitumor activity, including the Hedgehog signaling pathway, caspase-3 dependent apoptosis, cell cycle, and autophagy.