Beta-adrenoceptor action on pancreatic cancer cell proliferation and tumor growth in mice

There is growing evidence that some cancer progression is closely associated with beta- adrenoreceptors (β-ARs). However, the underlying mechanisms for β-ARs mediated proliferation of pancreatic cancer cell are poorly understood. In the current study, we evaluated the possible function of β-ARs on the proliferation of human pancreatic ductal adenocarcinomas (PDAC) cell line Panc-1 and explored β-ARsmediated downstream signal pathway.

Series of experiments, such as expression of β1- and β2-ARs on pancreatic cancer cell line Panc-1, β-ARsmediated downstream signal pathway activation as well as cell proliferation assay in vitro and in vivo were performed with immunofluorescence, Western blot analysis, BrdU incorporation assays and xenograft tumor growth respectively.

Non-selective β-ARs agonist Isoproterenol (ISO) significantly increased cell proliferation via β-ARs in a dose-dependent manner, with concomitant activation of ERK/MAPK signal pathway in Panc-1 cells. ISO increased expression level of phosphorylated ERK in Panc-1 cells. Furthermore, in vivo study showed that ISO enhanced xenograft tumor growth and this effect was suppressed by non-selective β-ARs antagonist (β-blocker), propranolol (PRO) treatment.

These findings suggest that the development and progression of PDAC is subject to significant modulation by ISO and PRO and the treatment with PRO may be useful for marker-guided cancer intervention of PDAC. Therefore, PRO may be developed a novel drug for the treatment and intervention of PDAC for its high specificity.