GB7 acetate is a galbulimima alkaloid obtained from Galbulimima belgraveana.However,information regarding its structure,biological activities,and related mechanisms is not entirely available.A series of spectroscopic analyses,structural degradation,interconversion,and crystallography were performed to identify the structure of GB7 acetate.The MTT assay was applied to measure cell proliferation on human colorectal cancer HCT 116 cells.The expressions of the related proteins were measured by Western blotting.Transmission electron microscopy(TEM),acridine orange(AO)and monodansylcadaverine(MDC)staining were used to detect the presence of autophagic vesicles and autolysosomes.A transwell assay was performed to demonstrate metastatic capabilities.Oxygen consumption rate(OCR)and extracellular acidification rate(ECAR)assays were performed to determine the mitochondrial oxidative phosphorylation(OXPHOS)and glycolysis activity of HCT 116 cells.The data showed that GB7 acetate suppressed the proliferation and colony-forming ability of HCT 116 cells.Pretreatment with GB7 acetate significantly induced the formation of autophagic vesicles and autolysosomes.GB7 acetate upregulated the expressions of LC3 and Thr172 phosphorylated adenosine 5'-monophosphate(AMP)-activated pro-tein kinase α(p-AMPKα),which are key elements of autophagy.In addition,GB7 acetate suppressed the metastatic capabilities of HCT 116 cells.Additionally,the production of matrix metallo-proteinase-2(MMP-2)and MMP-9 was reduced,whereas the expression of E-cadherin(E-cad)was upregulated.Furthermore,GB7 acetate significantly reduced mitochondrial OXPHOS and glycolysis.In conclusion,the structure of the novel Galbulimima alkaloid GB7 acetate was identified.GB7 acetate was shown to have anti-proliferative,pro-autophagic,anti-metastatic,and anti-metabolite capabilities in HCT 116 cells.This study might provide new insights into cancer treatment efficacy and cancer chemoprevention.

OBJECTIVE: To prepare warangalone-loaded thermosensitive liposomes (WLTSL) and evaluate its inhibitory effect on breast cancer cells . METHODS: MTT assay was used to assess the changes in proliferation of 3 breast cancer cell lines (MDA-MB-231, MCF7, and SKBR3) following treatment with warangalone, soy isoflavone and genistein. Colony-forming assay and wound healing assay was used to assess colony forming activity and migration of MDA-MB-231 cells treated with warangalone. The effect of warangalone on the expression of MMP2 and MMP9 in MDA-MB-231 cells was examined with Western blotting. The thermosensitive liposomes (TSL) and WLTSL were prepared using a thin film hydration method, and the morphology, size, encapsulation efficiency and stability of the prepared liposomes were characterized using transmission electron microscopy, dynamic light scattering scanning and UV spectrophotometry. MTT assay was used to examine the inhibitory effect of WLTSL on mouse breast cancer cells (4T1) . RESULTS: Warangalone showed stronger anti-proliferation effects than soy isoflavones and genistein in the 3 human breast cancer cell lines and significantly inhibited colony formation by MDA-MB-231 cells. Treatment with warangalone significantly inhibited migration of the breast cancer cells and down-regulated the cellular expressions of MMP2 and MMP9. The prepared TSL and WLTSL presented with a homogeneous, irregular spherical morphology, with a mean particle size of 56.23±0.61 nm, a polymer dispersity index of 0.241±0.014, a Zeta potential of -40.40±0.46 mV, and an encapsulation efficiency was 87.68±2.41%. WLTSL showed a good stability at 4 ℃ and 37 ℃ and a stronger inhibitory effect than warangalone in 4T1 cells. CONCLUSIONS Warangalone inhibits the proliferation, migration and invasion of breast cancer cells, and the prepared WLTSL possesses good physical properties and strong anti-breast cancer activity.
Animals ; Breast Neoplasms ; Cell Line, Tumor ; Cell Movement ; Cell Proliferation ; Humans ; Isoflavones ; Liposomes ; Mice