Protection against 7,12-dimethylbenzanthracene-induced tumour initiation by protein A in mouse skin.
Protein A is an immunostimulating glycoprotein obtained from Staphylococcus aureus Cowan I. Its antitumour activity is proven in various tumour models. Its ability to provide protection against tumour initiation by the chemical carcinogen 7,12-dimethylbenzanthracene (DMBA) has been investigated in the present study using a mouse skin model of two-stage carcinogenesis. Protein A was administered intraperitoneally (1 microgram/animal 20 g body wt.) twice a week for 2 weeks, prior to initiation by DMBA. The promotion was performed by twice weekly applications of 12-O-tetradecanoyl phorbol-13-acetate (TPA) (3 or 5 micrograms/animal in 100 microliters acetone). Protein A provided significant protection to animals from DMBA-induced tumour initiation as was observed by the decrease in cumulative number of tumours, percent of animals developing tumours, number of tumours per animal and rate of tumour growth. Our data indicate that protein A has anticarcinogenic properties.
Kumar
S
S
Industrial Toxicology Research Centre, Mahatma Gandhi Marg, Lucknow, India.
Shukla
Y
Y
Prasad
A K
AK
Verma
A S
AS
Dwivedi
P D
PD
Mehrotra
N K
NK
Ray
P K
PK
D015127:9,10-Dimethyl-1,2-benzanthracene; D000818:Animals; D000970:Antineoplastic Agents; D005260:Female; D051379:Mice; D012878:Skin Neoplasms / Q000139:chemically induced / Q000517:prevention & control*; D013205:Staphylococcal Protein A / Q000008:administration & dosage*; D016019:Survival Analysis
D000970:Antineoplastic Agents; D013205:Staphylococcal Protein A; D015127:9,10-Dimethyl-1,2-benzanthracene