Interleukin 7 receptor activates PI3K/Akt/mTOR signaling pathway via downregulation of Beclin-1 in lung cancer.

Interleukin-7(IL-7) can regulate proliferation and apoptosis of cell and also regulate tumor lymphangiogenesis, but whether it regulating autophagy of tumor cells is not well known. We study the relationship between IL-7 and some autophagy-related markers, Beclin 1 and mammalian target of rapamycin (mTOR) and the mechanism of IL-7 in regulating autophagy of human lung cancer cells. We detected expression of Beclin 1 and mTOR in lung cancer cells and their impact on the prognosis of lung cancer patients. Using Western blot and Reverse Transcription PCR, we found that IL-7 activates PI3 K/Akt/mTOR signaling pathway by downregulated the expression of Beclin 1 in lung cancer cell lines. In addition, the expressions of Beclin 1 and mTOR were well correlated with clinical stages and survival of human non-small cell lung cancer (NSCLC) patients. IL-7R, mTOR, and tumor stage were the independent prognosticators in lung cancer. Taken together, our results provided evidence that IL-7 activates PI3 K/Akt/mTOR signaling pathway via Beclin 1 to regulate autophagy in lung cancer cells.