checking same gene's expression levels in 5 cell lines

[Labnovice]

hello everyone,

I am still learning the nitty-gritty of performing a RTPCR...I usually run qRTPCR by the Taqman method, comparing gene expression levels between GFP and siRNA treated cells and look for downregulation. I use
RNAse P as the internal control for normalization and use transfected HEY cell line.
However, I m now confused as I am required to check for my gene's expression level in 5 different
cancer cell lines. Since i just have to quantitate the expression and not really compare against anything,
I am a little lost about how shd I go about running the samples and calculating using excel sheet.
SHould i consider one of the cell line as baseline i.e 1 and check expression levels?
and what shd be the other controls?

not sure if I am putting across my question effectively...can anyone reply please?

Thanks for any help...

[danfive]

I read Michael Pfaffl's papers on comparative gene expression and found them to be the most useful. I think you will find his formulas very straightforward.

Here are two articles I use as references:
A new mathematical model for relative quantification in real-time RT-PCR.
Relative expression software tool (REST) for group-wise comparison and statistical analysis of relative expression results in real-time PCR.