RESUMO
BACKGROUND: Bladder urothelial carcinoma (BUC) ranks second in the incidence of urogenital system tumors, and the treatment of BUC needs to be improved. Puerarin, a traditional Chinese medicine (TCM), has been shown to have various effects such as anti-cancer effects, the promotion of angiogenesis, and anti-inflammation. This study investigates the effects of puerarin on BUC and its molecular mechanisms. METHODS: Through GeneChip experiments, we obtained differentially expressed genes (DEGs) and analyzed these DEGs using the Ingenuity® Pathway Analysis (IPA®), Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) pathway enrichment analyses. The Cell Counting Kit 8 (CCK8) assay was used to verify the inhibitory effect of puerarin on the proliferation of BUC T24 cells. String combined with Cytoscape® was used to create the Protein-Protein Interaction (PPI) network, and the MCC algorithm in cytoHubba plugin was used to screen key genes. Gene Set Enrichment Analysis (GSEA®) was used to verify the correlation between key genes and cell proliferation. RESULTS: A total of 1617 DEGs were obtained by GeneChip. Based on the DEGs, the IPA® and pathway enrichment analysis showed they were mainly enriched in cancer cell proliferation and migration. CCK8 experiments proved that puerarin inhibited the proliferation of BUC T24 cells, and its IC50 at 48 hours was 218µmol/L. Through PPI and related algorithms, 7 key genes were obtained: ITGA1, LAMA3, LAMB3, LAMA4, PAK2, DMD, and UTRN. GSEA showed that these key genes were highly correlated with BUC cell proliferation. Survival curves showed that ITGA1 upregulation was associated with poor prognosis of BUC patients. CONCLUSION: Our findings support the potential antitumor activity of puerarin in BUC. To the best of our knowledge, bioinformatics investigation suggests that puerarin demonstrates anticancer mechanisms via the upregulation of ITGA1, LAMA3 and 4, LAMB3, PAK2, DMD, and UTRN, all of which are involved in the proliferation and migration of bladder urothelial cancer cells.
RESUMO
Xanthatin is a natural sesquiterpene lactone purified from Xanthium strumarium L., which has shown prominent antitumor activity against a variety of cancer cells. In the current study, we investigated the effect of xanthatin on the growth of glioma cells in vitro and in vivo, and elucidated the underlying mechanisms. In both rat glioma C6 and human glioma U251 cell lines, xanthatin (1-15 µM) dose-dependently inhibited cell viability without apparent effect on the cell cycle. Furthermore, xanthatin treatment dose-dependently induced glioma cell apoptosis. In nude mice bearing C6 glioma tumor xenografts, administration of xanthatin (10, 20, 40 mg·kg-1·d-1, ip, for 2 weeks) dose-dependently inhibited the tumor growth, but did not affect the body weight. More importantly, xanthatin treatment markedly increased the expression levels of the endoplasmic reticulum (ER) stress-related markers in both the glioma cell lines as well as in C6 xenografts, including glucose-regulated protein 78, C/EBP-homologous protein (CHOP), activating factor 4, activating transcription factor 6, spliced X-box binding protein-1, phosphorylated protein kinase R-like endoplasmic reticulum kinase, and phosphorylated eukaryotic initiation factor 2a. Pretreatment of C6 glioma cells with the ER stress inhibitor 4-phenylbutyric acid (4-PBA, 7 mM) or knockdown of CHOP using small interfering RNA significantly attenuated xanthatin-induced cell apoptosis and increase of proapoptotic caspase-3. These results demonstrate that xanthatin induces glioma cell apoptosis and inhibits tumor growth via activating the ER stress-related unfolded protein response pathway involving CHOP induction. Xanthatin may serve as a promising agent in the treatment of human glioma.