Asterosaponins from the Starfish Astropecten monacanthus Suppress Growth and Induce Apoptosis in HL-60, PC-3, and SNU-C5 Human Cancer Cell Lines

Abstract

Using various chromatographic experiments, six asterosaponins (1−6) were isolated from the MeOH extract of the Vietnamese starfish Astropecten monacanthus. The cytotoxic activities of the MeOH extract and six asterosaponins were evaluated on three human cancer cell lines, HL-60 (promyelocytic leukemia), PC-3 (prostate cancer), and SNU-C5 (colorectal cancer). Relative to the effects of the postitive control mitoxantrone, the MeOH extract (with IC₅₀ values ranging from 0.84±0.03 to 3.96±0.14 µg/mL) and astrosterioside D (5) (with IC₅₀ values ranging from 4.31±0.07 to 5.21±0.15 µM) exhibited potent cytotoxic effects against all three tested human cancer cell lines. In addition, the MeOH extract and astrosterioside D (5) have an effect on leading to apoptosis. Interestingly, the apoptosis of induction was accompanied by down-regulation of phosphatidyl inositol 3-kinase (PI3K)/AKT signaling and extracellular signal-regulated kinase (ERK) 1/2 mitogen-activated protein kinase (MAPK) signaling, and decrease of c-myc expression. Further studies are required to establish use of the asterosaponins from A. monacanthus as remedial and/or nutraceutical purposes.