From Scutellaria barbata to BZL101 in Cancer Patients: Phytochemistry, Pharmacology, and Clinical Evidence

Scutellaria barbata D.Don is a popular Chinese medicinal plant documented to treat cancer patients in traditional Chinese medicine (TCM). A botanical new investigational drug for breast cancer BZL101 (FDA IDN# 59521) was previously developed in the United States from the aqueous extract of the aerial parts from S. barbata. The early phase 1A and 1B clinical trials show its favorable toxicity profiles, good clinical tolerance, and promising efficacy for patients with metastatic breast cancer. To further evidence the phytopharmacology research, drug development, and anticancer use of this herb, a systematic literature review was performed herein on the phytochemistry, pharmacology, and specifically anticancer clinical evidence. A systematic review of the literature on phytochemical and pharmacological properties of the plant related to cancer treatment employed several web-based scientific databases including Wanfang (Chinese), Pubmed, Web of Science, and Elsevier. Key words included Scutellaria barbata, Ban Zhi Lian, cancer, and tumor. Based on critical quality criteria, only 8 out of 69 reports related to clinical studies of cancer patients in China. This review covered the available literature up to July 2019. The anticancer effects of S. barbata can be explained by the presence of various flavonoids and diterpenoids alkaloids. The underlying mechanisms are primarily summarized as cyclin/cyclin-dependent kinase (CDK)-modulated cell cycle arrest and mitochondria-mediated apoptotic death. The highly cancer-cell selective cytotoxicity and detoxifying effects of S. barbata contribute to a favorable clinical profile and enhanced quality of life for the cancer patient, thereby demanding further study as an adjuvant or alternative to conventional chemotherapy. The phytochemical and pharmacological studies reviewed strongly underpin a fundamental understanding of the anticancer activity of S. barbata and support ongoing clinical trials. The further safety verification and clinical trials are expected to progress S. barbata-based development to finally transform the traditional TCM herb S. barbata to the valuable anticancer drug.