ABSTRACT
Aim To investigate the effect of Ajuga decumbens(HBG), Poria cocos(FL) and their combination on the metastasis of invasive breast cancer cells and the related mechanisms.Methods We conducted several assays including cell adhesion assay, scratch assay and transwell invasion assay.Western blot analysis was employed to detect the expression of associated proteins of EMT and MAPK signaling pathway.Results FL,HBG and their combination could significantly inhibit the adhesion, migration and invasion of MDA-MB-231 and SK-BR-3 cells.HBG and FL had markedly synergistic effect, and the best compatibility ratio was 10 ∶1.HBG, FL and their combination could reverse EMT of breast cancer cells, which increased the levels of epithelial biomarkers, such as β-catenin, E-cadherin and ZO-1, and reduced the levels of mesenchymal biomarkers, such as vimentin.Moreover, treatment of the cells with HBG, FL and their combination resulted in marked inhibition of phosphorylation of ERK1/2, JNK and p38.Conclusions The combination of HBG and FL have the ability to inhibit breast cancer cell invasion by targeting the expression of MAPK pathway as well as suppressing the epithelial-to-mesenchymal transition.
ABSTRACT
Objective To evaluate the in vitro effect on tumor cell uptake,tumor imaging and in vivo biodistribution of 99Tcm-epidermal growth factor receptor (EGFR) mRNA antisense PNA probe mediated by cationic liposome.Methods The oligonucleotide with sequence complementary to part of the EGFR mRNA antisense PNA was hybridized in an anti-parallel orientation targeted PNA.PNA hybridization complexes were labeled with 99Tcm by ligand exchange.The assembly of lipofectamine and 99Tcm-labeled heteroduplex was achieved by electrostatic interactions,and the radiolabeled purity was determined by reversedphase HPLC (RP-HPLC).The disparities of cell uptake in SKOV3 cells and the differences of biodistribution and molecular imaging in BALB/c nude mice bearing SKOV3 xenografts between lipofectanine-mediated 99Tcm-EGFR mRNA antisense PNA (group 1) and 99Tcm-EGFR mRNA antisense PNA (group 2) were analyzed.Two-sample t (or t') test and Wilcoxon rank sum test were used for statistical analysis.Results The labeling rates of both group 1 and group 2 were more than 95％ within 6 h.The cell uptake at 1,2,4,6,12,24 h after injection was (28.90±1.12)％,(32.76±1.20)％,(38.20±3.11)％,(41.23±1.60)％,(46.63±1.55)％ and (46.78±2.14)％ in group 1,and was (3.51±0.39)％,(3.90±0.40)％,(4.69±0.18)％,(5.91±0.26)％,(5.30±0.22)％ and (5.39±0.17)％ in group 2 respectively (t'=47.11-58.67,Z=2.80,all P＜0.05).The retention ratios showed significant difference between the two groups (t'=7.25-11.55,Z=2.80,all P＜0.05).The SKOV3 tumor could be visualized in both groups at 1 h post injection but much better visualized in group 1.The T/NT ratios were higher in group 1 at all time points (t =3.96,t'=12.65-14.69,Z=2.83-5.29,all P＜0.05).The T/NT ratios at uptake peak were 5.02 and 3.95,respectively.The probe accumulated mainly in tumor,kidneys and liver.Tumor uptake increased with time ((1.49±0.09) ％ID/g and (2.15±0.21) ％ID/g at 1 h,(3.90±0.65) ％ID/g and (5.00±0.10) ％ID/g at 6 h) after lipofectamine treatment.The ratios of tumor to contralateral muscle were also higher in group 1 (t =11.24,t' =3.96-11.94,all P＜0.05).Conclusions Lipofectamine-mediation can significantly improve the intracellular delivery of radionuclide molecular probe.Lipofectamine-mediated 99Tcm-EGFR mRNA antisense PNA can greatly improve imaging contrast and visualization of EGFR-over-expressing tumors.
ABSTRACT
Objective To prepare the 99Tcm-labeled human epidermal growth factor receptor type 2 (HER2) affibody molecule ZHER2:342 and evaluate its receptor binding specificity in vitro.Methods The molecular ZHERa:342 was labeled with 99Tcm using the ligand exchange method.The labeling efficiency and radiochemical purity were measured by HPLC.The major factors,such as the mass of SnC12 and NaOH and reaction time were analyzed,and the optimal method was summarized.Cell binding kinetics and cellular retention of the probe were investigated in HER2-expressing SKOV-3 cells and MDA-MB-231 cells with low HER2 expression respectively.HER2 binding specificity of 99Tcm-ZHER2:342 was analyzed by a pre-injection of excess unlabeled ZHER2:342 to saturate HER2 receptors.One-way analysis of variance and two-sample t test were used.Results The optimal labeling procedure was as follows:5 μg (1 g/L) of ZHER2:342 was mixed with 5 μg of NaOH (1 g/L),then 8.8 μg SnC12(1 g/L,solution) was added,followed by 150 μl (37 MBq) 99TcmO4-solution,and finally the mixture was slightly vortexed and incubated for 1 h at room temperature.99TcmZHER2:342 was stable in vitro with a high labeling efficiency of (98.10± 1.73)％.The radiochemical purity was ＞ 98％,and was more than 85％ after the incubation for 24 h in saline and fresh human serum.The cell binding of 99Tcm-ZHER2:342 with HER2-expressing SKOV-3 cells gradually increased over time with a peak of (9.95± 1.02)％ at 6 h.The binding of 99Tcm-ZHER2:342 in SKOV-3 cells was significantly higher than that in MDA-MB-231 cells at every time point (5.68-9.88 vs 0.56-2.11 ; t:from-34.50 to-13.14,all P＜0.01).The labeled molecular probe retained the capacity to bind specifically to HER2-expressing SKOV-3 cells since the cell binding decreased from (9.95 ± 1.02) ％ to (2.11 ±0.27) ％ after receptor saturation (t =-13.14,P＜0.01).Conclusions 99Tcm-ZHER2:342 has a high labeling efficiency,good stability and optimal binding specificity.These characteristics enable it to be a promising molecular probe for HER2-targeting imaging.