Milk Thistle (Silybum marianum): Potential Role in Cancer Prevention

Milk thistle compounds have recently gained attention for their potential role in cancer prevention and treatment. Despite most evidence reporting this property refers to in vitro and animal studies, milk thistle flavonoids may provide insightful suggestions about novel chemopreventive agents. This narrative review provides an overview of the current understanding of milk thistle's effects on cancer cells and highlights possible mechanisms of action. The active compounds in milk thistle mainly exhibit antioxidant and anti-inflammatory effects, which protect cells and enhance their survival responses, even inhibiting cancer development. In addition, the compounds possess immunomodulatory properties crucial in preventing cancer progression. Another important mechanism is the induction of apoptosis, promoting cancer cell death and inhibiting tumour growth. These compounds inhibit angiogenesis, preventing tumour growth and spread. Due to their potential to inhibit cancer progression, they modulate cell signalling pathways, including the MAPK and PI3K/Akt pathways, which are involved in cell growth and survival. Although current research is promising, it is crucial to address the current gaps in knowledge about milk thistle compounds in cancer prevention and treatment. Future studies should focus on rigorous clinical trials, dose optimization, mechanistic investigations, combination therapy approaches, and personalized medicine to maximize their potential. Basic experimental evidence can provide new clues to establish clinical trials to improve cancer care and reassure patients and healthcare professionals.