OBJECTIVE:To prepare folic acid(FA)-loaded vincristine(VCR)nano liposome(VCR-nLip-FA)and to study its effects on human liver and lung cancer cells. METHODS:VCR-nLip-FA was prepared by ammonium sulfate gradient method,and particle size,Zeta-potential,encapsulation rate and release rate were investigated. Taking human liver cancer HepG2 cells and lung cancer A549 cells as example,uptake rate and inhibitory effect in vitro (5-80 μg/ml) were compared between VCR-nLip-FA and VCR-nLip. RESULTS:The particle size distribution,average particle size,average Zeta-potential,average encapsulation rate and 24 h accumulative release rate of VCR-nLip-FA were 98.1-159.0 nm,132.2 nm,-40.1 mV,(86.6±3.5)%(n=4)and(42.2± 2.6)%. Compared with VCR-nLip,there was no statistical significance in uptake rate of A549 cells to VCR-nLip-FA and inhibitory effect of VCR-nLip-FA on A549 cell viability (P>0.05);uptake rate of HepG2 cells to VCR-nLip-FA and inhibitory effect of VCR-nLip-FA on HepG2 cell viability increased significantly (P<0.01),in dose-dependent manner. CONCLUSIONS:Prepared VCR-nLip-FA can target anti-tumor drug to HepG2 cells efficiently,and highly inhibit the growth of HepG2 cells. But it has no higher effects on A549 cells.

Objective:To determine the expression of microRNA-188-5p (miR-188-5p) in cutaneous squamous cell carcinoma (CSCC) tissues and cells, and to assess the effect of its downregulation on the proliferation and invasion of CSCC cells.Methods:From November 2012 to October 2018, 50 surgically resected CSCC tissue specimens and 50 paracancerous normal skin tissue specimens were collected from the First Affiliated Hospital of Xinxiang Medical College in Henan Province. Real-time fluorescence-based quantitative PCR (qPCR) was employed to determine the expression of miR-188-5p in CSCC tissues, paracancerous normal skin tissues, CSCC cell lines SCL-1, A431 and HSC-5, and a human immortalized keratinocyte line HaCaT. Cultured A431 and HSC-5 cells were both divided into 2 groups: miR-188-5p inhibitor group and negative control group, which were transfected with a miR-188-5p inhibitor and its negative control respectively. Then, qPCR was performed to determine the relative expression level of miR-188-5p (expressed as 2 -△△Ct), and cell counting kit-8 (CCK8) and Transwell assays were conducted to assess cellular proliferative activity and invasive ability respectively in the above groups. Dual-luciferase reporter assay was performed to investigate interactions between miR-188-5p and phosphatase and tensin homologue deleted on chromosome 10 (PTEN), and Western blot analysis to determine the protein expression of PTEN, total Akt (t-Akt) and phosphorylated Akt (p-Akt). Two independent samples were compared by using t test. Results:The relative expression level of miR-188-5p was significantly higher in the CSCC tissues (5.213 ± 3.138) than in the paracancerous normal skin tissues (1.010 ± 0.364, t = 9.187, P < 0.001), and significantly higher in the SCL-1, A431 and HSC-5 cells (3.858 ± 0.163, 7.068 ± 0.262 and 4.572 ± 0.413, respectively) than in the HaCaT cells (1.079 ± 0.300, t = 17.890, 21.110 and 8.737, respectively, all P < 0.05). Compared with the negative control group, the miR-188-5p inhibitor group showed significantly decreased miR-188-5p expression in both A431 and HSC-5 cells (both P < 0.01), and decreased proliferative activity and invasive ability of both A431 and HSC-5 cells (all P < 0.05). Dual-luciferase reporter assay showed that the downregulation of miR-188-5p significantly increased the expression of PTEN, but inhibited the expression of p-Akt in A431 and HSC-5 cells. Conclusion:MiR-188-5p is highly expressed in CSCC tissues and cells, and the downregulation of miR-188-5p may inhibit the proliferative activity and invasive ability of CSCC cells by regulating the PTEN/Akt pathway.