ABSTRACT
Objective@# To explore whether RhoA plays a role in the migration and invasion of the salivary adenoid cystic carcinoma cell lines SACC-LM and SACC-83.@*Methods@#Total RNA and total protein were extracted from 20 salivary adenoid cystic carcinoma (SACC) and normal adjacent tissues frozen in liquid nitrogen to detect RhoA expression. RhoA-siRNA was constructed to transfect two cell lines (SACC-LM and SACC-83) for cytological experiments. The research included an experimental group (RhoA-siRNA transfection), negative control group (siRNA-NC transfection) and blank group by transient transfection with liposomes. Expression of RhoA mRNA and protein as well as the protein expression of biomarkers of epithelial-mesenchymal transition (EMT) were analyzed, including E-cadherin, N-cadherin, and Vimentin. Furthermore, the changes in invasion and migration of cells in each group were analyzed by comparing the number of transmembrane cells in the Transwell assay and the results of the scratch test.@*Results@#Compared with normal adjacent tissues, RhoA protein and mRNA levels increased in SACC tissues. Compared with the control group, the relative expression levels of RhoA mRNA and protein decreased (P < 0.01), the relative expression levels of E-cadherin protein increased, and the relative expression levels of N-cadherin and vimentin protein increased in the experimental group (P < 0.01). Additionally, the trial results revealed that RhoA knockdown restrained cell migration and invasion (P < 0.01).@*Conclusion @#RhoA expression increased in SACC tissue. Silencing RhoA in vitro could effectively restrain cell migration and invasion in SACC-LM and SACC-83 cells through the regulation of EMT signaling pathways.
ABSTRACT
ABSTRACT Screening promising L. thermophiles with high productivity, high efficiency and strong adaptability are very important in lactic acid industry. For this purpose, 80MeV/u carbon ions were applied to irradiate L. thermophiles. After high-throughput screening, a mutant, named SRZ50, was obtained. Different carbon sources or nitrogen sources were provided to investigate carbon or nitrogen source utilization between mutant SRZ50 and wild type, and different fermentation periods were also chose to study fermentation characteristic between mutant SRZ50 and wild type. The results showed that mutant SRZ50 exhibited the enhanced L-(+)-lactic acid production from wild type. When glucose or fructose was the sole carbon source, the L(+)-lactic acid production by mutant SRZ50 was both the highest, respectively, 23.16 ± 0.72 g/L or 23.24 ± 0.66 g/L, which had a significant increase from that of wild type (P<0.01), following obvious increase in biomass (P<0.05). When yeast powder was the sole nitrogen source, it can promote mutant SRZ50 to accumulate the highest L-(+)-lactic acid accumulation, which also had a significant increase from that of wild type (P<0.01). Under different fermentation periods, it was obtained that mutant SRZ50 all exhibited significant increase in L-(+)-lactic acid accumulation from wild type. In conclusion, a mutant strain with improved production profiles for L-(+)-lactic acid, was obtained, indicating that heavy ions can be an efficient tool to improve metabolic product accumulations in microbes.