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Build a cell-cycle based tumor growth model

From: Feng Yang <fyangusa>
Date: Thu, 17 Jul 2008 16:49:14 +0800

Dear nmusers:
Recently I am trying to build a cell-cycle based tumor growth model, i.e.
tumor size = G1+ S + G2 + M. Meanwhile, I have quite a few simultaneous
biomarkers to characterize the cycle behaviors. Those biomarkers could be
calculated based on the population of G1, S, G2, and M. I have the
following puzzles needed to be addressed:

1) In my data file, what is the CMT number I should give to those
observations (such as tumor size and many biomarkers)? By the way, I need
CMT to specify/initialize the corresponding compartment. Since I am not
quite sure how to use L2 and PCMT, I tried many times, all failed except the
following foolish way:
I create one more compartment to hold the tumor size:
and in my data file, I put the CMT compartment created (iTUMOR) into the
observation of tumor size.

However, for all other biomarkers, there is no way to write this kind of
DADT equations. How could I solve this in a smart way?

2) Since some biomarker data are collected based on certain time point,
saying t0. In other words, they are relative fold-changes compared to the
vehicle at t0. Therefore, I need to save the intermediate population of G1,
S, G2 and M at t0, as constants, which will be used to scale the later-on
populations so that the model predictions are comparable with the

However, in the both block $DES and $ERROR, there is no way to save these
intermediate populations as global variables or constants. I guess, I have
to use MSFO to separate the simulation to many sections? But it am not
sure how to do it.

Your thoughts and feedback are really appreciated! Thanks a lot!


Received on Thu Jul 17 2008 - 04:49:14 EDT

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