Network pharmacology analysis, molecular docking integrated experimental verification reveal β-sitosterol as the active anti-NSCLC ingredient of Polygonatum cyrtonema Hua by suppression of PI3K/Akt/HIF-1α signaling pathway

Polygonatum cyrtonema Hua (Huangjing) is a Chinese herb that is considered by ancient Chinese healers to have the effect of nourishing yin and moisturizing the lungs. It is clinically used to treat diseases of the pulmonary system, including non-small cell lung cancer. However, the precise active components and underlying mechanisms of Huangjing in the context of treating NSCLC remain uncertain. This study aimed to explore the active components and mechanisms of Huangjing for the treatment of NSCLC by means of data mining, network pharmacology, and in vitro and vivo experiments. First, the main active compounds and key targets of Huangjing were predicted by network pharmacology. The potential key targets of Huangjing were molecularly docked with the main active compounds using Pymol. In vivo, we verified whether Huajing and its main active compound have anti-lung cancer effects. Key targets were verified by PCR and immunohistochemistry. In vitro, we verified the effects of Huangjing's main active compound on the proliferation, apoptosis, and migration of A549 cells by CCK-8, colony formation, wound healing assay, and flow cytometry. Key targets and signaling pathway were validated by PCR and Western blot. The network pharmacology results suggested that β-sitosterol was the main active substance. TP53, JUN, AKT1, MAPK14, ESR1, RELA, HIF1A, and RXRA were potential targets of Huangjing. Molecular docking results suggested that MAPK14, HIF-1α, and RXRA docked well with β-sitosterol. In vivo tests also confirmed that Huangjing could significantly inhibit the growth of lung cancer tumors, while PCR and immunohistochemistry results suggested that the expression of HIF-1α was significantly decreased. Critically, KEGG analysis indicated that the PI3K/Akt/HIF-1α signaling pathway was recommended as one of the main pathways related to the anti-NSCLC effect of Huangjing. We conducted in vitro experiments to confirm the significant impact of β-sitosterol on the proliferation, apoptosis, migration, and colony formation of A549 cells. Furthermore, our findings indicate that a high dosage of β-sitosterol may effectively decrease the expression of HIF-1α, AKT1, JUN and RELA in A549 cells. Similarly, in vitro experiments also revealed that high doses of β-sitosterol could inhibit the PI3K/Akt/HIF-1α signaling pathway. We discovered Huangjing and its main active ingredient, β-sitosterol, can reduce HIF-1α, AKT1, JUN and RELA expression and decrease non-small cell lung cancer growth through the PI3K/Akt/HIF-1α signaling pathway.