1/delta Ct vs delta delat CT - (Jan/17/2013 )

I'm writing to seek assistance. I recently read a paper where the expression of several genes was analysed using qPCR in cancer cell lines but the results were analysed by 1/delta CT.

Figure 1 of : Soll C et al. Clin Cancer Res 2012;18:5902-5910

I've never encountered this method before?

Thank you very much.

Never seen it either.
But I guess they can use it assuming all genes have identical efficiency. It allows to plot several genes side by side in the graph. The ratio mentioned there is not teling anything about the relative abundancy between samples (like sample 1 has twice of the sample 2 transcript), it only shows where is less and where is more and allows to compare if it is similar in other genes.

But as I understand they only used it as a screening to see receptor expression at all in the cell lines, which was validated then by different analysis with normal vs tumor sample, so it just a visual aid.