RÉSUMÉ
OBJECTIVE To analyze the chemical components that were the absorbed in blood and liver tissue of rats after intragastric administration of aqueous extract from Abrus cantoniensis， and to speculate its possible metabolic pathways， providing reference for basic analysis of pharmacological substance in A. cantoniensis. METHODS Male SD rats were randomly divided into A. cantoniensis group （0.63 g/kg， calculated by crude drug） and blank group； they were given relevant drug solution/ultrapure water intragastrically. After a single dose， plasma and liver samples of rats in each group were collected. UPLC-Q-TOF/MS technology was used to identify chemical components that were absorbed in the blood and liver tissue of rats. RESULTS Totally， 30 chemical constituents were identified from the water extracts of A. cantoniensis， including alkaloids， flavonoids， organic acids， iridoids （such as L-abrine， schaftoside， isoshaftoside）. Ten prototype components and nine metabolites （such as decarboxylation and sulfation metabolites of protocatechuic acid， reduced sulfated metabolites of p-hydroxybenzoic acid） were identified from plasma samples； six prototype components and five metabolites （such as sulfated metabolites of p-hydroxybenzoic acid， decarboxylation and sulfation metabolites of p-hydroxybenzoic acid） were identified from liver samples. The main metabolic pathways included hydroxylation， demethylation， methylation， sulfation， glucuronidation， etc. CONCLUSIONS Alkaloids， flavonoids and organic acids are the main components of the aqueous extract from A. cantoniensis that are absorbed into the blood and liver， their metabolism mainly involves hydroxylation，demethylation， and sulfation.
RÉSUMÉ
Nasopharyngeal carcinoma (NPC) is a malignant tumor that mainly occurs in East and Southeast Asia. Although patients benefit from the main NPC treatments (e.g., radiotherapy and concurrent chemotherapy), persistent and recurrent diseases still occur in some NPC patients. Therefore, investigating the pathogenesis of NPC is of great clinical significance. In the present study, replication factor c subunit 4 (RFC4) is a key potential target involved in NPC progression via bioinformatics analysis. Furthermore, the expression and mechanism of RFC4 in NPC were investigated in vitro and in vivo. Our results revealed that RFC4 was more elevated in NPC tumor tissues than in normal tissues. RFC4 knockdown induced G2/M cell cycle arrest and inhibited NPC cell proliferation in vitro and in vivo. Interestingly, HOXA10 was confirmed as a downstream target of RFC4, and the overexpression of HOXA10 attenuated the silencing of RFC4-induced cell proliferation, colony formation inhibition, and cell cycle arrest. For the first time, this study reveals that RFC4 is required for NPC cell proliferation and may play a pivotal role in NPC tumorigenesis.