Abstract
Abstract
Colorectal cancer (CRC) remains a major global health challenge owing to its therapeutic resistance and high recurrence rates, underscoring the need for mechanism-based interventions.
Strobilanthes cusia
(Nees) Kuntze, a medicinal herb traditionally used for inflammatory disorders, contains bioactive diterpenoids and alkaloids with anticancer potential. However, the molecular mechanisms underlying this process in CRC remain unclear. This study evaluated sequential Soxhlet extracts of
S. cusia
leaves using integrated in-vitro and in-silico methods. Among the n-hexane, chloroform, ethanol, and aqueous fractions, the ethanolic extract exhibited the highest cytotoxicity against HCT-116 and SW-620 CRC cells, with IC
50
values of 54.37 and 77.52 µg/mL, respectively. GC–MS analysis identified 13 phytoconstituents, and andrographolide was isolated for the first time from
S. cusia
and structurally characterized using UV–Visible, FTIR, and NMR spectroscopy. Network pharmacology analysis identified checkpoint kinase 1 (CHEK1) as a central target. Molecular docking revealed favorable binding of andrographolide to CHEK1 (− 6.40 kcal/mol), comparable to that of the reference compound (− 6.30 kcal/mol), and molecular dynamics simulations confirmed complex stability. In vitro validation demonstrated dose-dependent apoptosis and proliferation inhibition in both cell lines, with significantly lower IC
50
values at 48 h (isolated: 10.52 ± 1.91µM; commercial: 8.96 ± 9.35µM) than at 24 h. These findings identify CHEK1 as a mechanistically relevant target and support further translational investigation of
S. cusia-derived
andrographolide in CRC therapy.