چکیده (انگلیسی):

Objective: To explore the role of the abnormal expression of miRNAs in the development
process of non-small cell lung cancer and the feasibility of ultrasound microbubblemediated
gene therapy after transfecting antisense miRNA-224 and miRNA-122a plasmids
into non-small cell lung cancer A549 cells.
Methods: Antisense miRNA-224 and miRNA-122a plasmids were transfected into nonsmall
cell lung cancer A549 cells on the optimal ultrasound microbubble-mediated
condition. We set up a control group. The cell proliferation activity, apoptosis, invasion
ability were detected by MTT assay, Annexin V-PE, Transwell invasion experiment and
colony formation assay, respectively.
Results: The expression of miRNA-224 decreased and the expression of miRNA-122a
rose after the plasmids of target genes were transfected into non-small cell lung cancer
A549 cells, and there were significant differences when compared with those of the
control group (P < 0.05). After the plasmids of target genes were transfected into A549
cells, the growth of antisense miRNA-224 and miRNA-122a were inhibited, and the
differences were significant as compared with the control group (P < 0.05). Besides, the
inhibition of miRNA-122a group was the most significant and there was statistically
significant difference as compared with miRNA-224 group (t = −4.694, P = 0.009). After
the plasmids of target genes were transfected into A549 cells, the proportion of apoptotic
cells increased, the invasive cells were decreased and the clone ability reduced, and also
there was a significant difference as compared with those of the control group (P < 0.05).
What's more, the apoptotic peak appeared in miRNA-122a group. Its invasion ability
decreased most obviously (40.25 ± 3.97/visual field), the number of clone ability was
104.93 ± 4.87 and the inhibitory effect was the most obviously. There was statistically
significant difference as compared with other groups (P < 0.05).
Conclusions: A549 cells transfected by ultrasound microbubble-mediated antisense
miRNA-224 and miRNA-122a plasmids possessed good transfection efficiency. The cell
growth, invasion and colony-forming abilities of transfected A549 cells were suppressed,
which laid a solid foundation for the gene therapy of non-small cell lung cancer.