Phytochemical Characterization, Antimicrobial Activity and In Vitro Antiproliferative Potential of Alchemilla vulgaris Auct Root Extract against Prostate (PC-3), Breast (MCF-7) and Colorectal Adenocarcinoma (Caco-2) Cancer Cell Lines

Despite the proven biological activity of the aerial part extract of Alchemilla vulgaris, scarce information is available about the activity of the root extract. This encouraged us to initiate the current investigation to study the cytotoxic activity of A. vulgaris methanolic root extract against various cancer cell lines in vitro, along with its antimicrobial activity and phytochemical screening. MTT assay was applied to test the cytotoxic effect against the prostate (PC-3), breast (MCF-7) and colorectal adenocarcinoma (Caco-2), together with normal Vero cells. Flow cytometry was employed to assess cell cycle arrest and apoptosis vs. necrosis in PC-3 cells. The expression of apoptosis-related genes (BAX, BCL2 and P53) was quantified by qRT-PCR analysis. The obtained results showed strong antiproliferative activity on the three cancer cell lines and the normal Vero cells in a dose-dependent manner. A high selectivity index (SI) was recorded against the three cell lines with PC-3 cells showing the highest SI and the lowest IC(50). This effect was associated with cell cycle arrest at G1 phase and induction of total apoptosis at 27.18% being mainly early apoptosis. Apoptosis induction was related to the upregulation of the proapoptotic genes P53 and BAX and the downregulation of the antiapoptotic gene BCL2. Additionally, the extract demonstrated in vitro antibacterial activity against Agrobacterium tumefaciens, Serratia marcescens and Acinetobacter johnsoni. Additionally, it showed antifungal activity against Rhizoctonia solani, Penicillium italicum and Fusarium oxysporium. Seven phenolic acids and seven flavonoids were detected. The predominant phenolic acids were cinnamic and caffeic acids, while hisperdin and querestin were the principal flavonoids. These findings provide clear evidence about the promising proapoptotic effect of A. vulgaris root extract, which contributes to laying the basis for broader and in-depth future investigations.