Dopamine increases the efficacy of anticancer drugs in breast and colon cancer preclinical models.
OBJECTIVE
Because neurotransmitter dopamine inhibits vascular permeability factor/vascular endothelial growth factor (VEGF)-induced angiogenesis and as anti-VEGF agents act synergistically with anticancer drugs, we therefore investigated whether dopamine can increase the efficacies of these drugs.


METHODS
The effect of dopamine was investigated in human breast cancer-(MCF-7) and colon (HT29) cancer-bearing mice. Experimental groups received either dopamine or doxorubicin or dopamine plus doxorubicin in MCF-7 tumor-bearing mice, and either dopamine or 5-fluorouracil or dopamine plus 5-fluorouracil in HT29-bearing mice. Thereafter, tumor growth, angiogenesis, tumor cell apoptosis, life span, and the effect of dopamine on the growth and survival of tumor cells in vitro were determined. Finally, the effects of dopamine on tumor vascular permeability; on VEGF receptor-2, mitogen-activated protein kinase, and focal adhesion kinase phosphorylation; and also on the proliferation and migration of tumor endothelial cells were investigated.


RESULTS
Dopamine, in combination with anticancer drugs, significantly inhibited tumor growth and increased the life span when compared with treatment with dopamine or anticancer drugs alone. Dopamine had no direct effects on the growth and survival of tumor cells. The antiangiogenic action of dopamine was mediated by inhibiting proliferation and migration of tumor endothelial cells through suppression of VEGF receptor-2, mitogen-activated protein kinase, and focal adhesion kinase phosphorylation.


CONCLUSIONS
Our study shows that dopamine significantly enhances the efficacies of commonly used anticancer drugs and also indicates that an inexpensive drug like dopamine, which is being extensively used in the clinics, might have a role as an antiangiogenic agent for the treatment of breast and colon cancer.
Sarkar
Chandrani
C
Signal Transduction and Biogenic Amines Laboratory, Kolkata, India.
Chakroborty
Debanjan
D
Chowdhury
Uttio Roy
UR
Dasgupta
Partha Sarathi
PS
Basu
Sujit
S
D000818:Animals; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000098:blood supply / Q000188:drug therapy*; D002199:Capillary Permeability / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D003110:Colonic Neoplasms / Q000098:blood supply / Q000188:drug therapy*; D004298:Dopamine / Q000494:pharmacology*; D004317:Doxorubicin / Q000627:therapeutic use; D042783:Endothelial Cells / Q000187:drug effects; D005472:Fluorouracil / Q000627:therapeutic use; D051416:Focal Adhesion Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors; D006801:Humans; D051379:Mice; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D010766:Phosphorylation; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000037:antagonists & inhibitors; D023041:Xenograft Model Antitumor Assays
D000970:Antineoplastic Agents; D004317:Doxorubicin; D040301:Vascular Endothelial Growth Factor Receptor-2; D051416:Focal Adhesion Protein-Tyrosine Kinases; D020928:Mitogen-Activated Protein Kinases; D005472:Fluorouracil; D004298:Dopamine