The meaning of the numbers on IC50 Table sheet in CCLE_GNF_data_090613

Hi Depmap team,
I am not experienced interpreting the big data like Depmap, so I feel so sorry to ask this basic and easy question for you.

I want to know the meaning of the numbers on IC50 table sheet in CCLE_GNF_data_090613.
I think the numbers are not concentration for drugs because the range of the concentration of drugs is from 0.0025 to 8uM as CCLE_NP24.2009_Drug_data_2015.02.24 was shown.
I guess it is sensitivity factor things… but I cannot understand the meaning of the numbers.

one more thing,
please let me know the meaning of >20, <0.001221.



IC50 is a fit parameter for a dose-response curve, estimated from a set of drug assays. The IC50 describes the concentration of the drug required to obtain 50% of the maximum inhibition effect. Because of this it has units of concentration, even though it can exceed the bounds of the actual drug concentrations used in the assay. The values of >20 and <0.001221 would then indicate the high and low bounds for this estimated parameter, since as the parameter gets too far from the bounds of the assay the error gets large. Let me know if you have other follow up questions!

DepMap Team

Thanks for the reply.

Taegeun Bae