ABSTRACT
Objective To analyze the differential expressions of miR-146a,miR-206,miR-223 and let-7c-1,such as cell differentiation-related miRNAs,in CXCR4-positive and CXCR4-negative subsets of the Lewis lung cancer cell lines(LLC).Methods CXCR4-positive and CXCR4-negative subsets were isolated from LLC by immunomagnetic beads sorting,and then their total cellular RNA were extracted by Trizol,expression of 4 miRNAs were detected by real-time fluorescence quantitative PCR(TaqMan probe),and potential target genes of miRNA whose differential expression was the most significant were predicted.Immunohistochemistry was carried out to confirm differential expression of the key molecule of certain research value within CXCR4-positive and CXCR4-negative subsets growing tumor tissue,and a BLAST search was performed to identify homologies of its 3′UTR.Results Compared to CXCR4-negative subsets,the expression of 4 miRNAs were lower in CXCR4-positive subsets,and expression of miR-223 had the most significant difference(Fold change=8.26).By softwares forecasting,miR-223 had potential target sites of IGF1R,IGFBP5,Pik3cb,ELK-1 and E2F1 mRNA,such as key molecular of IGF1R signaling pathway.The expression of IGF1R of CXCR4-positive subsets growing tumor tissue was significantly higher than that of CXCR4-negative subsets.Conclusion miR-223 is lowly expressed in CXCR4 positive cells from Lewis lung carcinoma cell lines.Position 238～244 nt and 688～695 nt in target sequences of 3′UTR of IGF1R mRNA was highly homologous by screening.Close correlation is found between miR-223 and IGF1R signaling pathway.The mechanisms underlying this biologically important finding need to be further explored.
ABSTRACT
Purpose:To study the synergistic inhibitory effects of huachansu plus vinorelbine on cell growth in mice bearing Lewis lung cancer. Methods:Fifty mice bearing Lewis lung cancer were randomly divided into control group,cyclophosphamide group (CTX),huachansu group (HCS), vinorelbine group (VNB) and huachansu plus vinorelbine group (HV). Each group included ten mice. Normal saline (0.2 ml),cyclophosphamide (30 mg/kg),huachansu (5 ml/kg),vinorelbine (6.7 mg/kg),huachansu (5 ml/kg) plus vinorelbine group (6.7mg/kg) were injected intraperitoneally,respectively in the five groups. After the drugs were administered for seven days,all mice were sacrificed and the tumors were weighed. The tumor inhibitory rates were calculated and compared among the five groups of mice. The growth cycles of Lewis lung cancer were analyzed with flow cytometry. Results:The tumor inhibitory rates of HCS,VNB and HV group were 42.86% ,45.68%,53.44%,respectively. The percentage of S phase of cell cycle was increased in HCS and the percentage of G 2 /M phase increased in VNB,and both increased in HV group. Conclusions:There exists synergistic inhibitory effect on Lewis lung cancer between huachansu and vinorelbine and the mechanisms could correlate with their synergistic effect on cell growth cycles.
ABSTRACT
Objective To observe the anti-tumor effect of ethaselen on transplanted liver cancer(H22)and Lewis lung cancer mice.Methods The transplanted liver cancer(H22)and Lewis lung cancer mice models were established.Each genus consisted of 60 mice,which were divided into control,CTX,and three ethaselen dose groups,respectively,with 12 mice in each.Intraperitoneal injection(ip.)of three dosages was performed once a day through the abdominal wall separately,from the second to the eighth day after cancer was transplanted.On the eleventh day,six mice in each group were killed to calculate the tumor inhibition ratio and observe the cell cycle by flow cytometry,and the others were observed for the life extension ratio.Results When ethaselen was given at the dosage of 25,12.5 and 6.3 mg/kg,the tumor inhibition ratio was 52.5%,43.6% and 30.2%,and the life extension ratio was 56.6%,38.7% and 14.2% in the transplanted liver cancer(H22)mice,respectively.The tumor inhibition ratio was 43.8%,29.6% and 18.9%,and the life extension ratio was 47.3%,17.9% and 6.3% in the transplanted Lewis lung cancer mice,respectively.Compared with that of the control,the apoptosis ratio was obviously increased in each group,and there was obviously induced S phase arrest in 25.0 mg/kg(P