Background: Aurora A kinase represent a feasible target in cancer therapy.
Objective: To evaluate the proteomic response of human liver carcinoma cells to alisertib (ALS)
and identify the molecular targets of ALS, we examined the effects of ALS on the proliferation,
cell cycle, autophagy, apoptosis, and chemosensitivity in HepG2 cells.
Method: The stable-isotope labeling by amino acids in cell culture (SILAC) based quantitative
proteomic study was performed to evaluate the proteomic response to ALS. Cell cycle distribution
and apoptosis were assessed using flow cytometry and autophagy was determined using flow
cytometry and confocal microscopy.
Results: Our SILAC proteomic study showed that ALS regulated the expression of 914 proteins, with
407 molecules being up-regulated and 507 molecules being down-regulated in HepG2 cells. Ingenuity
pathway analysis (IPA) and KEGG pathway analysis identified 146 and 32 signaling pathways were
regulated by ALS, respectively, which were associated with cell survival, programmed cell death, and
nutrition-energy metabolism. Subsequently, the verification experiments showed that ALS
remarkably arrested HepG2 cells in G2/M phase and led to an accumulation of aneuploidy via
regulating the expression of key cell cycle regulators. ALS induced a marked autophagy in a
concentration- and time-dependent manner via the phosphatidylinositol 3-kinase (PI3K)/protein
kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling pathway. Autophagy inhibition
promoted the pro-apoptotic effect of ALS, indicating a cyto-protective role of ALS-induced
autophagy. ALS increased the chemosensitivity of HepG2 cells to cisplatin and doxorubicin.
Conclusion: Taken together, ALS induces autophagy and cell cycle arrest in HepG2 cells via
PI3K/Akt/mTOR-mediated pathway. Autophagy inhibition may promote the anticancer effect of
ALS and sensitize the chemotherapy in HepG2 cells.