Alkaloids from Corydalis saxicola and their antiproliferative activity against cancer cells.

Eight undescribed alkaloids named corydalisine D-K (1-7), including one isoquinoline benzopyranone alkaloid (1), one benzocyclopentanone alkaloid (2), four benzofuranone alkaloids (3, 4, and 5a/5b) and two protoberberine alkaloids (6 and 7), along with fourteen known ones, were isolated from the Corydalis saxicola. Their structures, including absolute configurations, were unambiguously identified using spectroscopic techniques, single-crystal X-ray diffraction and electron circular dichroism calculation. Compounds 2, 14 and 21 exhibit antiproliferative activity against five cancer cell lines. The aporphine alkaloid demethylsonodione (compound 14), which exhibited the best activity (IC50 = 3.68 ± 0.25 µM), was subjected to further investigation to determine its mechanism of action against the T24 cell line. The molecular mechanism was related to the arrest of cell cycle S-phase, inhibition of CDK2 expression, accumulation of reactive oxygen species (ROS), induction of cell apoptosis, inhibition of cell migration, and activation of p38 MAPK signaling pathway. The results indicated that 14 could be used as a potential candidate agent for further development of anti-bladder transitional cell carcinoma.

Pentagalloylglucose suppresses the growth and migration of human nasopharyngeal cancer cells via the GSK3ß/ß-catenin pathway in vitro and in vivo.

BACKGROUND: Nasopharyngeal carcinoma (NPC) is a type of malignant squamous cell tumour originating from the nasopharynx epithelium. Pentagalloylglucose (PGG) is a natural polyphenolic compound that exerts anticancer effects in many types of tumours. However, the role and underlying mechanism of PGG in NPC cells have not been fully defined. PURPOSE: This study aimed to investigate the anticancer activity of PGG as well as the potential mechanism in NPC cells. METHODS: The effects of PGG on the proliferation, apoptosis and cell cycle distribution of CNE1 and CNE2 cells were assessed by MTT and flow cytometry assays. Cell migration was evaluated using wound healing and transwell assays. The expression of microtubule-associated protein 1 light chain 3 beta (LC3B) was observed by immunofluorescence staining. Western blotting was used to explore the levels of related proteins and signalling pathway components. Furthermore, the effects of PGG on NPC cell growth were analysed in a xenograft mouse model in vivo using cisplatin as a positive control. RESULTS: PGG dose-dependently inhibited the proliferation of CNE1 and CNE2 cells. PGG regulated the cell cycle by altering p53, cyclin D1, CDK2, and cyclin E1 protein levels. PGG induced apoptosis and autophagy in NPC cells and elevated the Bax/Bcl-2 ratio and the protein levels of LC3B. Moreover, PGG decreased NPC cell migration by increasing E-cadherin and decreasing N-cadherin, vimentin and CD44 protein levels. Mechanistically, PGG treatment downregulated p-mTOR and ß-catenin expression but upregulated p-p38 MAPK and p-GSK3ß expression. In addition, PGG significantly inhibited NPC cell tumour growth and lung metastasis in vivo. CONCLUSION: PGG may suppress cell proliferation, induce apoptosis and autophagy, and decrease the metastatic capacity of NPC cells through the p38 MAPK/mTOR and Wnt/ß-catenin pathways. The present study provides evidence for PGG as a potential therapy for NPC.

The neurotrophic and antineuroinflammatory effects of phenylpropanoids from Zanthoxylum nitidum var. tomentosum (Rutaceae).

Three novel lignans (1, 5 and 6) and two novel quinic acids (16 and 17) along with 15 known phenylpropanoids were obtained from the ethanol extract of Zanthoxylum nitidum var. tomentosum (Rutaceae). Their structures were confirmed by comprehensive spectroscopic data (NMR and HRESIMS), and the absolute configurations of all novel compounds were elucidated based on electronic circular dichroism (ECD) spectroscopic data. The production of nitric oxide (NO) in BV-2 microglial cells induced through lipopolysaccharide (LPS) was used to evaluate in vitro anti-neuroinflammatory activity of compounds 1-20. Compound 2, 3, 7 and 16 showed excellent inhibition of LPS-induced NO production. The structure-activity relationships of the isolates were investigated. In addition, the mechanism of action of 2 was elucidated by RT-PCR and Western blotting analysis, which indicated that it reduced neuroinflammatory mainly through NLRP3/caspase1 signaling pathways in LPS-induced BV2 microglial cells.

In vitro study of anti-ER positive breast cancer effect and mechanism of 1,2,3,4-6-pentyl-O-galloyl-beta-d-glucose (PGG).

Breast cancer is one of the most common malignancies and the leading cause of women's death, most of breast cancers are estrogen receptor-positive (ER+) breast cancer which can develop into advanced stage from early stage with treatment resistance. The purpose of this study was to investigate anti-ER+ breast cancer effects of 1,2,3,4,6-penta-O-galloyl-ß-d-glucose (PGG) and its possible mechanisms. Cell viability was analyzed by MTT assay. The cell cycle distribution and apoptosis were detected by Flow cytometry. The expressions of cell proliferation- and apoptosis-related proteins were determined by western blot and immunofluorescence staining. The results showed PGG induced cytotoxicity and decreased viability of ER+ breast cancer T-47D and BT-474 cells. Flow cytometry analysis revealed that cell cycle was blocked in S phase at lower dose (25 µM PGG), and G1 phase at higher dose (50 or 75 µM PGG). One of the underlying mechanisms of the anti-cancer effect exerted by PGG was owed to inhibition of the expression of HURP, an up-regulated protein in human hepatocellular carcinoma which is closely related to tumor proliferation, invasion and metastasis. PGG affected cell cycle- or apoptosis-related proteins such as cyclin D1, Bcl-2 and Bax. These data suggest that PGG exerts anti-ER+ breast cancer effects. In this sense, our study provides new alternative therapies to treat breast cancer.

[Effect of gallnut extract on nasopharyngeal carcinoma 5-8F cells and its mechanism].

OBJECTIVE: To determine the biological activity of ellagic acid extracted from gallnut against nasopharyngeal carcinoma and its molecular mechanism. METHODS: Nasopharyngeal carcinoma 5-8F cells were treated with 2, 4, 6 µg/mL ellagic acid for 48 h in vitro. The cell proliferation and cell apoptosis were analyzed by MTT and Hoechst33258 stain. The cell cycle and protein expression were measured by flow cytometry and Western blot. RESULTS: Ellagic acid inhibited the proliferation of 5-8F cells. The inhibition rates were (29.35±4.95)%, (53.32 ±4.44)% and ( 61.75 + 6.93)%, respectively, with significant difference from the control group (P<0.01). S phase cells in the experimental groups were (25.47±0.74)%, (28.08±1.41)% and (35.49±0.66)%, respectively, with significant difference (P<0.01) from the control group (21.26±0.70)%. Cells in the experimental groups showed nuclear pyknosis, karyorrhexis and poptotic cell morphology. The expression of COX-2 and stathmin in 5-8F cells was down-regulated with increased drug concentration. CONCLUSION: Ellagic acid extracted from gallnut has activity against nasopharyngeal carcinoma cells, and its mechanism may be related to down-regulated expression of COX-2 and stathmin.