Mechanism of Qiyu Sanlong Prescription in Inhibiting "Addiction" of Lung Cancer A549 Cells to miRNA21 / 中国实验方剂学杂志

ABSTRACT

Objective:To investigate the molecular mechanism of Qiyu Sanlong prescription （QYSL） in inhibiting the "addiction" of lung cancer A549 cells to miRNA21. Method:The human lung cancer A549 cells were routinely passaged and divided into the blank group， blank serum group， QYSL-containing serum group， and siRNA group. The prepared QYSL-containing serum was used for intervention， with the optimal concentration and action time determined in previous studies. The protein and mRNA expression levels of miRNA21 and related molecules in its target phosphatase and tensin homolog deleted on chromosome 10 （PTEN）/phosphatidylinositol 3-kinase （PI3K） signaling pathway were detected by real-time polymerase chain reaction （Real-time PCR） and Western blot assay. Result:The comparison with the blank serum group revealed that the mRNA expression levels of miRNA21 in the QYSL-containing serum group and the siRNA group were decreased， while the PTEN mRNA expression in the QYSL-containing serum group was increased， showing significant differences （<italic>P</italic><0.01）. Compared with the blank serum， the QYSL-containing serum and siRNA significantly down-regulated PI3K and mammalian target of rapamycin （mTOR） mRNA expression （<italic>P</italic><0.01）， whereas the QYSL-containing serum did not change the mRNA expression of protein kinase B （Akt）. The protein expression levels of PTEN in the QYSL-containing serum group and the siRNA group were obviously elevated in contrast to that in the blank serum group （<italic>P</italic><0.05）. Meanwhile， the protein expression levels of phosphorylated Akt （p-Akt） and phosphorylated mTOR （p-mTOR） evidently declined in the QYSL-containing serum group （<italic>P</italic><0.05）， but there was no significant reduction in total Akt and mTOR protein expression. The PI3K protein expression was slightly down-regulated， with no statistical significance. Conclusion:QYSL inhibits the transcription of miRNA21， increases the expression of PTEN， and reduces the expression of key molecules in PI3K/Akt/mTOR signaling pathway， thus mildly inhibiting the "addiction" of lung cancer cells to oncogenes and blocking their proliferation.