ABSTRACT
OBJECTIVE@#To explore whether casticin (CAS) suppresses stemness in cancer stem-like cells (CSLCs) obtained from human cervical cancer (CCSLCs) and the underlying mechanism.@*METHODS@#Spheres from HeLa and CaSki cells were used as CCSLCs. DNA methyltransferase 1 (DNMT1) activity and mRNA levels, self-renewal capability (Nanog and Sox2), and cancer stem cell markers (CD133 and CD44), were detected by a colorimetric DNMT activity/inhibition assay kit, quantitative real-time reverse transcription-polymerase chain reaction, sphere and colony formation assays, and immunoblot, respectively. Knockdown and overexpression of DNMT1 by transfection with shRNA and cDNA, respectively, were performed to explore the mechanism for action of CAS (0, 10, 30, and 100 nmol/L).@*RESULTS@#DNMT1 activity was increased in CCSLCs compared with HeLa and CaSki cells (P<0.05). In addition, HeLa-derived CCSLCs transfected with DNMT1 shRNA showed reduced sphere and colony formation abilities, and lower CD133, CD44, Nanog and Sox2 protein expressions (P<0.05). Conversely, overexpression of DNMT1 in HeLa cells exhibited the oppositive effects. Furthermore, CAS significantly reduced DNMT1 activity and transcription levels as well as stemness in HeLa-derived CCSLCs (P<0.05). Interestingly, DNMT1 knockdown enhanced the inhibitory effect of CAS on stemness. As expected, DNMT1 overexpression reversed the inhibitory effect of CAS on stemness in HeLa cells.@*CONCLUSION@#CAS effectively inhibits stemness in CCSLCs through suppression of DNMT1 activation, suggesting that CAS acts as a promising preventive and therapeutic candidate in cervical cancer.
Subject(s)
Female , Humans , Cell Line, Tumor , HeLa Cells , Neoplastic Stem Cells/metabolism , RNA, Small Interfering/metabolism , Uterine Cervical Neoplasms/metabolismABSTRACT
Based on the ITS2 and psbA-trnHsequences, molecular biological identification and genetic relationship of Fritillaria cirrhosa with its relative species were carried out. In this paper, the PCR-RFLP method specified by the Chinese Pharmacopoeia was performed on all samples at first. Secondly, the ITS2 and psbA-trnH sequences of all samples were amplified. Then, the amplified products were used to analyze the genetic distance, construct the phylogenetic tree, assess the identification efficiency, and evaluate the genetic relationship as well. The result showed that all the samples were divided into two groups by PCR-RFLP method. The samples in the first group, including Fritillaria ussuriensis, Fritillaria thunbergii and Fritillaria pallidiflora, could not be digested by SmaI, while the other samples in the second group, including Fritillaria mellea, Fritillaria sinica, Fritillaria cirrhosa var. ecirrhosa Franch, Fritillaria unibracteata var. longinectarea and Fritillaria cirrhosa, could be digested by SmaI. Then, ITS2 and psbA-trnH sequences of all samples were obtained. The length of various ITS2 sequences were distributed from 235 to 239 bp, and the average intra- and inter-specific genetic distance were 0.001 and 0.022, respectively. NJ tree showed that all samples were separated into "Northern Fritillaria" group (Fritillaria ussuriensis and Fritillaria pallidiflora) and "Southern Fritillaria" group (Fritillaria thunbergii, Fritillaria mellea, Fritillaria sinica, Fritillaria cirrhosa var. ecirrhosa Franch, Fritillaria unibracteata var. longinectarea and Fritillaria cirrhosa). The latter group could be further divided into Fritillaria thunbergii and Fritillaria cirrhosa subgroup, and the species in Fritillaria cirrhosa subgroup had close phylogenetic relationships. The length of psbA-trnH sequences was distributed from 337 to 373 bp, and the intra- and inter-specific genetic distance were 0.263 and 0.329, respectively. The samples in this paper could not be clustered effectively by NJ tree. This indicated that the ITS2 sequences were not only able to identify Fritillaria cirrhosa with its partial relative species quickly and accurately, but also clarify the relationship between different Fritillaria species. Therefore, it provided an important theoretical foundation for the development of molecular markers, effective protection, and rational development and utilization of Fritillaria resources.