Secondary Metabolites of Saussurea costus Leaf Extract Induce Apoptosis in Breast, Liver, and Colon Cancer Cells by Caspase-3-Dependent Intrinsic Pathway

Abstract

Background. Apoptosis, a major form of programmed cell death, plays a vital role in regulating tissue development and maintenance of homeostasis in eukaryotes. Apoptosis can occur via a death receptor-dependent extrinsic or a mitochondrial-dependent intrinsic pathway and can be induced by various chemotherapeutic agents. In this study, the anticancer activity of Saussurea costus and its mode of intervention in human cancer cells of breast, colon, and liver were investigated. Results. In this study, the bioactives of S. costus leaves were extensively extracted in five solvents of different polarity. The cytotoxicity and anticancer effect of the extracted secondary metabolites were investigated against breast (MCF-7), liver (HepG2), and colon (HCT116) cancer cell lines using a Sulphorhodamine B (SRB) assay. Secondary metabolites extracted using hexane, methanol, ethyl acetate, and chloroform had the highest cytotoxicity and thus the greatest anticancer effect on all the cancer cell lines tested (IC50; ranging from 0.25 to 2.5 μg/ml), while butanol was comparatively less active (IC50; ranging from 23.2 to 25.5 μg/ml). Further investigation using DNA flow cytometry and fluorescent microscopy revealed that the extract arrested the cells in the G1 phase of cell cycle and induced apoptosis. Furthermore, the elevated expression level of proapoptotic proteins and decreased expression level of antiapoptotic proteins confirmed that the intrinsic (mitochondrial) pathway was involved in mediating the apoptosis of cancer cells upon treatment with S. costus extract. These results altogether suggest that S. costus could be a potential anticancer agent. Conclusion. These results suggest that the S. costus extract is the potential source of the secondary metabolites that could be used as anticancer agent to treat diverse cancers of breast, colon, and liver.

Saussurea lappa Exhibits Anti-Oncogenic Effect in Hepatocellular Carcinoma, HepG2 Cancer Cell Line by Bcl-2 Mediated Apoptotic Pathway and Mitochondrial Cytochrome C Release

“…The treatment group showed fragmented shrunken and marginated nuclei in contrast to the normal and large nucleus in the untreated cells, proving the apoptotic potential of the extract (Figure 7). Similar results were seen in a recent study [40].…”

“…There was relative up-regulation of pro-apoptotic caspase-3 and bax genes and down-regulation of the antiapoptotic bcl-2 gene in S. lappa n-butanol root extract-treated HepG2 cells compared to the untreated group (Figure 9). Ko et al reported cytotoxic effects of Saussurea lappa on AGS gastric cancer cells, and they determined that there was no effect of S. lappa on bcl-2 expression but had strong stimulating effect on bax gene expression [40]. In line with our study, Moon et al demonstrated that S. lappa extract induced the proteolytic processing of caspase-3, a significant increase of Bax, and marked reduction of Bcl-2 in KB human oral cancer cells [39].…”

“…The antiradical assays of S. lappa n-butanol root extract were measured by DPPH free radical scavenging assay. In brief, 3 mL of DPPH solution (#RM2798-1G, DPPH, Himedia, Mumbai, India) (0.003% DPPH in methanol) was mixed with 1 mL of different concentrations (20,40,60,80, and 100 µg/mL) of extract and ascorbic acid as separate standards. The tubes were kept in the dark for 30 min at room temperature and then measured for optical density at 517 nm using a UV-Vis spectrophotometer.…”

Myrtus Communis Leaf Extract - A Source of Secondary Metabolites Exhibiting Anticancer and Antimycobacterial Activities

“…2.4. Cell cycle distribution using DNA ow cytometry DNA ow cytometry for cell cycle distribution was performed as described by Shati Ali A et.al [20]. In brief, the cells were treated with the IC 50 of leaf extract for 48 h and collected by trypsinization, washed with ice-cold PBS, and re-suspended in 0.5 ml of PBS.…”

“…al. [20] (Abcam Inc., Cambridge Science Park, and Cambridge, UK). Brie y, cells were treated with different concentrations for 48 hr.…”