Hi,

I had an experience for tumor developing using carcinogenic compound (DMBA). Unfortunately, very small tumor appeared just in 2-3 animals after 6 months!!! I eventually found that the DMBA was expired. Therefore, I had to change my protocol to develop a tumor in shorter time!! The following link is my paper, may be it helps you.

https://www.researchgate.net/publication/228512463_Induction_of_mammary_gland_tumor_in_female_Sprague-Dawley_rats_with_LA7_cells

Good luck,

Article Induction of mammary gland tumor in female Sprague-Dawley ra...

hi Fatemeh Shamsabadi, I have already read your article. Thanks. In my previous lab we have been using DMBA method. The induction rate was quite high when we started the experiment at the proper time of the year (taking into account hormone changes etc in female rats). I have, however, a problem with describing data. After adding my anticancer compound, the tumors started to shrink. After a few weeks, there was a regrowth. That could be explained (see figure in http://jnm.snmjournals.org/content/50/Suppl_1/1S.full.pdf ) but...then there was again a decrease in tumor volume. The compound was added only once. I have been trying to find something about tumor kinetics. They suggest sometimes gompertzian kinetics tumor-growth curve.... but I am lost. I really don`t know how to explain my results. I was really trying to find an answer, but since my compound is quite new, there is no publications about its effect on tumors. I think that first shrinkage was a direct effect of the compound and the latter was due to increase in endogenous defence systems. What do you think? Could anyone help, please?

Hi,

the 2nd shrinkage might be caused by necrosis of the tumor..

Hamid Reza Mirzaei, Thank you! I will try to include your suggestion in my discussion.