Evaluating the therapeutic potential of picrosides in breast cancer cell lines: a systematic scoping review

Breast cancer is the second most frequently diagnosed cancer after lung cancer and is the leading cause of death in women across the globe. TNBC is an aggressive tumor and shows resistance to existing targeted treatment which result in its poor prognosis. Despite multiple efforts to discover the targeted therapies for TNBC treatment, chemotherapy is the only systematic treatment. No clinical trials are available on the novel therapeutic agent for treatment of TNBC. So, there is an urgent need to examine the process of novel therapeutic effects on TNBC. The review investigates the types of picroside extracts utilized under different experimental conditions in in vitro studies on breast cancer cell lines to evaluate their anticancer activity. A comprehensive literature search was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The search covered four major databases, MEDLINE, Web of Science, Embase, and Scopus-for studies published between 2013 and 2024 that evaluated the effects of picrosides on cell viability in breast cancer cell lines, as well as related molecular studies. The key data items extracted included the type of breast cancer cell lines, interventions [Picrorhiza kurroa extract (PE), kutkin (KT), kutkoside (KS), picroside I (PS), and picroside II (PII)], exposure durations (24, 48, and 72 h), and measures of cell viability. This review has been prospectively registered with PROSPERO (CRD42024615448). We included six studies after removing 13 duplicates and title and abstract screening from total 23 records that reported seven breast cancer cell lines. Of the reported six studies, the IC50 of picrosides in three studies for breast cancer cells at 24, 48, and 72 h was in the range from 35 to 50 µg/mL. IC50 with polyherbal combination of nine herbs including picroside was 150.29 µg/mL, which could be due to the combination of different herbal extracts. Two studies have reported the IC50 values of picrosides at lower concentration (2.46-4.92 µg/mL). No consistent behavior was observed for the effects of picroside between and within individual breast cancer cell lines. Drug discovery using breast cancer cell lines needed optimal design of experimental conditions and detailed examination of picrosides effects on different cellular and molecular mechanisms in breast cancer cells for developing it as future drug for breast cancer treatment.