Article

COX-2 silencing inhibits cell proliferation in A549 cell

The Chinese-German Journal of Clinical Oncology 01/2011; 10(7):423-427. DOI: 10.1007/s10330-011-0829-0

ABSTRACT ObjectiveThe aim of this study was to explore the effects on malignant proliferation of A549 cell by silencing cyclooxygenase (COX)-2.

MethodsIn the present study, we constructed three siRNA vectors producing small interference RNA. The siRNA vectors and the vacant
vectors were transfected into A549 cell with lipofectamine respectively and the transfected cell strains were constructed.
The change of COX-2 expression levels was examined by Western blot and RT-PCR. The effects on the proliferation of lung cancer
cells were studied by cell growth curve, clonogenic assay and xenograft assays.

ResultsThe siRNA expression vectors produced marked effects in A549 cell but the inhibited effects were different. The effect of
psi-10 was best and the mRNA and protein levels of COX-2 reduced 61.2% and 56.2% respectively in A549-si10 cell in contrast
to the control. The growth of A549 cell slowed and the colony formation rate reduced after silencing COX-2. In xenograft assays,
the growth speeds of tumor became slow and the numbers of tumor reduced after silencing COX-2.

ConclusionThe si10 target of COX-2 has the best silencing effect in A549 cell and the best inhibition effect on malignant proliferation
of A549 cell in vivo and in vitro.

Key wordscyclooxygenase (COX)-2–A549 cell–malignant proliferation

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