Regression of NMU-induced mammary tumors with the combination of melatonin and 9-cis-retinoic acid

Melancon, K.; Cheng, Q.; Kiefer, T.L.; Dai, J.; Lai, L.; Dong, C.; Yuan, L.; Collins, A.; Thiyagarajah, A.; Long, S.; Hill, S.M.

doi:10.1016/j.canlet.2005.01.005

« Previous Next »Cancer Letters
Volume 227, Issue 1 , Pages 39-48, 8 September 2005

Regression of NMU-induced mammary tumors with the combination of melatonin and 9-cis-retinoic acid

K. Melancon
- Department of Transplantation and Surgery, Mayo Clinic, Rochester, MN 555905, USA
- Department of Surgery, New Orleans, LA 70112, USA
- Tulane Cancer Center, Tulane University Health Sciences Center, New Orleans, LA 70112, USA
Q. Cheng
- Department of Structural and Cellular Biology, New Orleans, LA 70112, USA
T.L. Kiefer
- Molecular and Cellular Biology Graduate Program, New Orleans, LA 70112, USA
J. Dai
- Department of Structural and Cellular Biology, New Orleans, LA 70112, USA
L. Lai
- Department of Structural and Cellular Biology, New Orleans, LA 70112, USA
C. Dong
- Department of Structural and Cellular Biology, New Orleans, LA 70112, USA
L. Yuan
- Department of Structural and Cellular Biology, New Orleans, LA 70112, USA
A. Collins
- Department of Structural and Cellular Biology, New Orleans, LA 70112, USA
A. Thiyagarajah
- Department of Environmental Health Sciences, New Orleans, LA 70112, USA
S. Long
- Department of Surgery, New Orleans, LA 70112, USA
- Tulane Cancer Center, Tulane University Health Sciences Center, New Orleans, LA 70112, USA
S.M. Hill
- Department of Surgery, New Orleans, LA 70112, USA
- Molecular and Cellular Biology Graduate Program, New Orleans, LA 70112, USA
- Tulane Cancer Center, Tulane University Health Sciences Center, New Orleans, LA 70112, USA
- Corresponding author. Address: Tulane Cancer Center, Molecular and Cellular Biology Grad., Tulane University Health Sciences Center, New Orleans, LA 70112, USA. Tel.: +1 504 988 6456; fax: +1 504 988 1687.

Received 18 August 2004; accepted 7 January 2005.

Abstract

A significant increase in tumor regression was induced in N-nitroso-N-methylurea-induced mammary tumors in rats treated with the combination of melatonin and 9-cis-retinoic acid (9cRA). Treatment groups included: control (ethanolic saline), 9cRA (30mg/kg chow/day), melatonin 500μg/day, melatonin 1000μg/day, melatonin 500μg/day+9cRA and melatonin 1000μg/day+9cRA. Rats treated with the lower dose of melatonin 500μg+9cRA show the greatest degree of tumor regression (78%), with 54% undergoing complete regression and a significant increase in apoptotic cells observed by TUNEL Assay. Furthermore, tumor multiplicity and burden were significantly decreased by the combination of melatonin and 9cRA.