*1.1. Current Status of PCa*

PCa is the most common malignant tumor in the urinary system of men in Europe and the United States. According to the data of the World Cancer Report 2020, the number of new cases of PCa registered globally was 1,414,259, ranking second in the prevalence of male malignant tumors [1], with the highest incidence in Oceania and North America, followed by Europe. Rates in Africa and Asia are lower than in developed countries. In PCa, the incubation period is very long and is usually diagnosed in older men. At the time of diagnosis, about 90% of PCa is organ-confined or locally advanced [2,3]. Localized PCa is treated with active monitoring and local radiotherapy or resection of the prostate to achieve good treatment effects, but with the progression of the disease, advanced PCa can only be treated with surgery or chemical castration of androgen deprivation therapy (ADT), but most patients develop ADT resistance and progress to castration-resistant PCa (CRPC) in about 18 to 36 months, and once progress to CRPC is made, existing drugs and methods are often difficult to obtain effective results [4]. At the same time, the treatment of advanced PCa is still troubled by the highly toxic side effects of synthetic drugs [5]. Therefore, there is an urgent need to develop a new drug that is safe, effective, affordable, and easy to manufacture to treat androgen-independent PCa (AIPC). In recent years, natural products from fungi, plants, and animals for medical trends are emerging. Medicinal plants used for

**Citation:** Li, W.; Huang, T.; Xu, S.; Che, B.; Yu, Y.; Zhang, W.; Tang, K. Molecular Mechanism of Tanshinone against Prostate Cancer. *Molecules* **2022**, *27*, 5597. https://doi.org/ 10.3390/molecules27175594

Academic Editor: Saverio Bettuzzi

Received: 18 July 2022 Accepted: 22 August 2022 Published: 30 August 2022

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the purpose of health care in the world have increased dramatically. This is mainly because they have definite efficacy and low toxicity. In fact, more than half of the currently available drugs come from natural products [6].
