TITLE:
Gemcitabine and Doxorubicin Combination Enhance the Cytotoxic Effect to Pancreatic Cancer Cells BxPC3 and PANC1 through UMP/CMP Kinase 1
AUTHORS:
Shuxian Chen, Xu Wang, Xianghui Ye, Jian Jin
KEYWORDS:
Gemcitabine, Deoxycytidine Analog, Doxorubicin, CMPK1, Pancreatic Cancer
JOURNAL NAME:
Journal of Biosciences and Medicines,
Vol.5 No.10,
October
27,
2017
ABSTRACT: Background: Gemcitabine is a deoxycytidine analog, which is
used as first-line agent for pancreatic cancer therapy, and
its efficacy relied on its intracellular conversion to active triphosphate
form. However, administration with gemcitabine still has limited effect on the
overall survival of patients with pancreatic cancer. Objective: We aimed
to study the combination effect of gemcitabine and doxorubicin to pancreatic
cancer cells BxPC3 and PANC1, and unveil the mechanism. Methods: The
study was performed in pancreatic cancer cells PANC1 and BxPC3, the contribution of UMP/CMP
kinase 1 (CMPK1) to gemcitabine in PANC1 and BxPC3 cells was measured by transfection
of CMPK1 plasmid or CMPK1 siRNA treatment to adjust the expression of CMPK1 in
the cells; then analyzed the cell vitality and migration after treated with 1%
IC50 of doxorubicin and gemcitabine or only with gemcitabine; the
activity of CMPK1 and the effect of doxorubicin to the reaction was measured by
HPLC assay in vitro; at last, docking
analysis by computer was used to calculate the possible interaction sites of
CMPK1 to DOX. Results: The sensitivity of PANC1 and BxPC3 cells to
gemcitabine was improved when increasing the expression of CMPK1, and decreased
when knockout CMPK1 by CMPK1 siRNA in BxPC3 cells; when combined with
doxorubicin, the sensitivity of PANC1 and BxPC3 cells to gemcitabine also increased,
and the cells migration reduced; we further found out that by adding 10 μM
doxorubicin, the catalyzing activity of CMPK1 elevated about 2 times in vitro; the docking result showed that
the association of CMPK1 to DOX was mainly by hydrogen bond and ionic
interaction. Conclusion: CMPK1 can catalyze gemcitabine to its active form
within the cells so that the sensitivity of the cells to gemcitabine elevated, and doxorubicin may enhance the cytotoxic
effect to pancreatic cancer by up-regulate the activity of CMPK1, the
combination of these deoxycytidine analogs with DOX might exert better efficacy.