Antiproliferative effects of Salvia on breast cancers.

Breast cancer is the most common cancer diagnosed in female adults, with 2.3 million new cases worldwide in 2020. Plants have been used in traditional medicine and are a potential source of pharmaceuticals. One example is the large Lamiaceae (mint) family. The Salvia genus, commonly known as the sages, is the largest genus in Lamiaceae with almost 900 known species. Salvia lyrata (lyre-leaved sage) has a history of Native American medicinal use to treat cancers and other ailments resulting in this plant being referred to as ‘cancer weed.’ Extracts were produced from the leaves of S. lyrata, S. lyrata ‘Purple Knockout,’ and Salvia officinalis (common sage, a naturalized European plant) and assessed for phytochemical content. All extracts were then assessed for ability to limit proliferation in three breast cancer cell lines (MDA-MB-231, BT474, and T47D). Extracts of S. officinalis had the greatest impact on cell proliferation when compared to both S. lyrata extracts. To expand upon these findings, acid hydrolysis was employed to remove glycosides and thus influence extract polarity to increase antiproliferation activity. Acid hydrolysis increased the anticancer activity of S. officinalis in the T-47D cell line. Luteolin and apigenin were identified in extracts and were tested for antiproliferative activity and found to have the greatest activity of the phenolic compounds tested against the MDA-MB-231 and T-47D cell lines. Finally, to test for possible mechanism of action, an apoptosis assay and qRT-PCR assay were employed to evaluate apoptosis as a mechanism of antiproliferative activity against MDA-MB-231 cell line with S. officinalis extracts.