Effect Of Anesthetics On IGF-1-induced Cell Malignancy In Breast Cancer And The Underlying Mechanism

Breast cancer(BC)is one of the most common tumors among females,which affects about 12% of women worldwide.Insulin like growth factor-1(IGF-1)is one of the most important contributors to mammary tumorigenesis,but the underlying mechanisms have not been fully understood yet.Surgical resection is the most effective treatment for BC,however,an increasing number of studies have reported that aeanesthetic-analgesics technique during cancer surgery,especially the widely used opioids,may have a negative effect on cancer recurrence and metastasis.Objective Observing the effect of several widely used anesthetic/ analgesics on IGF-1-induced cell proliferation in human breast cancer cell line MCF-7 cells.Further study was planned to investigate the role of mu opioid receptor(MOR)activation on IGF-1-induced tumorigenesis in MCF-7,looking forward to providing valuable information for the clinical application of anesthesia and analgesia in these patients.Methods Human breast cancer cell line MCF-7 cells were cultured in vitro.In Part 1,Cell Counting Kit(CCK-8)cell viability assay and western blot were conducted respectively to determine the effects of propofol,midazolam,etomidate and morphine on IGF-1-induced cell proliferation and Akt activation.In Part 2,MCF-7 cells,which expressed mu opioid receptor,were exposed to IGF-1 and the protein expression of MOR was tested with western blot.Seven groups were then assigned: untreated group(control group),IGF-1-treated group,DAMGO-treated group,MNTX-treated group,and IGF-1 plus DAMGO-treated group(I+D group),IGF-1 plus MNTX-treated group(I+M group),IGF-1 plus DAMGO and MNTX-treated group(I+D+M group).Cell proliferation was measured using flow cytometry and CCK-8.Cell migration and invasion were tested with Transwell.Laser scanning confocal microscope(LSCM)was adopted to observe the MOR endocytosis.Activation of Akt and Src were determined by western blot.Ly294002 was used to inhibit PI3K/Akt signaling pathway and then cell proliferation was tested.Results 1.All of midazolam,etomidate and morphine could facilitate IGF-1-induced cell proliferation and Akt activation in MCF-7,whereas propofol had no effect.2.IGF-1 dose-and time-dependently increased the expression of MOR in MCF-7 cells.Cell proliferation,migration and invasion were significantly higher in I+D group than control and IGF-1 group,furthermore,these effects could be blocked by MNTX.3.Compared with DAMGO group and IGF-1 group,agonist-induced endocytosis of MOR significantly increased in I+D group.Both of p-Akt and p-Src expression were significantly higher in I+D group than control group and IGF-1 group;these effects could be blocked by MNTX as well.Ly294002 could significantly inhibit the proproliferation effects of IGF-1 and DAMGO.Conclusion The data from the current study demonstrate that several frequently used anesthetics and analgesics,including midazolam,etomidate and morphine,may facilitate IGF-1-induced proliferative effect in human breast cancer cell line MCF-7 cells.Expression level of MOR in MCF-7 cells is upregulated upon IGF-1 treatment.Activating MOR significantly increases IGF-1-induced cell proliferation,migration and invasion.The underlying molecular mechanisms may be related to the activation of Src/Akt signaling pathway.