Alisertib induces cell cycle arrest and autophagy and suppresses epithelial-to-mesenchymal transition involving PI3K/Akt/mTOR and sirtuin 1-mediated signaling pathways in human pancreatic cancer cells.

Pancreatic cancer is the most aggressive cancer worldwide with poor response to current therapeutics. Alisertib (ALS), a potent and selective Aurora kinase A inhibitor, exhibits potent anticancer effects in preclinical and clinical studies; however, the effect and underlying mechanism of ALS in the pancreatic cancer treatment remain elusive. This study aimed to examine the effects of ALS on cell growth, autophagy, and epithelial-to-mesenchymal transition (EMT) and to delineate the possible molecular mechanisms in human pancreatic cancer PANC-1 and BxPC-3 cells. The results showed that ALS exerted potent cell growth inhibitory, pro-autophagic, and EMT-suppressing effects in PANC-1 and BxPC-3 cells. ALS remarkably arrested PANC-1 and BxPC-3 cells in G2/M phase via regulating the expression of cyclin-dependent kinases 1 and 2, cyclin B1, cyclin D1, p21 Waf1/Cip1, p27 Kip1, and p53. ALS concentration-dependently induced autophagy in PANC-1 and BxPC-3 cells, which may be attributed to the inhibition of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR), p38 mitogen-activated protein kinase (p38 MAPK), and extracellular signal-regulated kinases 1 and 2 (Erk1/2) but activation of 5'-AMP-dependent kinase signaling pathways. ALS significantly inhibited EMT in PANC-1 and BxPC-3 cells with an increase in the expression of E-cadherin and a decrease in N-cadherin. In addition, ALS suppressed the expression of sirtuin 1 (Sirt1) and pre-B cell colony-enhancing factor/visfatin in both cell lines with a rise in the level of acetylated p53. These findings show that ALS induces cell cycle arrest and promotes autophagic cell death but inhibits EMT in pancreatic cancer cells with the involvement of PI3K/Akt/mTOR, p38 MAPK, Erk1/2, and Sirt1-mediated signaling pathways. Taken together, ALS may represent a promising anticancer drug for pancreatic cancer treatment. More studies are warranted to investigate other molecular targets and mechanisms and verify the efficacy and safety of ALS in the treatment of pancreatic cancer.

Effect of the GLP-1 analog exendin-4 and oxaliplatin on intrahepatic cholangiocarcinoma cell line and mouse model.

The influence of Glucagon-like peptide-1 (GLP-1) and Exendin-4 on development of intrahepatic cholangiocarcinoma (ICC) is evaluated in the study. In vitro tests, including acute toxicity test, cell colony formation assays, cells proliferation and apoptosis, transwell assay, were performed. An ICC in situ tumor animal model was established. Then, animals were randomly divided into four groups (n = 6): control, Exendin-4 treatment, oxaliplatin treatment and Exendin-4-oxaliplatin treatment. Animals in the Exendin-4 treatment and Exendin-4-oxaliplatin treatment groups received a subcutaneous injection of Exendin-4 (100 µg/kg/day) for 1 week, and then received oxaliplatin (10 mg/kg/week) by tail vein injection. Animals in the control group received PBS. Immunohistochemistry tests were used for PCNA, Ki67, Caspase 3 expression in tumor tissue. Results show that that, after incubation of human cholangiocarcinoma cell lines, HuCCTI and GLP-1, or HuCCTI and Exendin-4, colony formation number was sharply decreased. However, GLP-1, HuCCTI or Exendin-4 did not affect the colony of normal cells. Combination treatment with oxaliplatin and Exendin-4 can significantly inhibit tumor cells' proliferation and promote apoptosis. The combined effect is stronger than that of oxaliplatin or Exendin-4. Combination treatment with oxaliplatin and Exendin4 can significantly decrease Ki67 and PCNA proteins' expression in subcutaneous tumors of nude mice. The inhibitory effect of Combination treatment with oxaliplatin and Exendin4 is clearly stronger than that of oxaliplatin. In addition, Combination treatment with oxaliplatin and Exendin4 can significantly increase Caspase3 protein positive expression. In short, these results show that combination treatment with oxaliplatin and Exendin4 can inhibit tumor cells' proliferation, and promote apoptosis.