Measurement of pka for cancer characterization

A method for characterizing a carcinoma in a subject, the method comprising the steps of

• incubating a mixture comprising a sample of a bodily fluid derived from the subject, a PKA peptide substrate, a phosphorylation agent, and a reducing agent, the mixture having an oxidation reduction potential value that is less than −150 mV or greater than −20 mV, and
• detecting phosphorylated substrate formed in the incubated mixture.

A method for determining the activity of extracellular cyclic AMP dependent protein kinase A (PKA) in a sample derived from a bodily fluid and previously unfrozen for the phosphorylation of the PKA substrate, the method comprising the steps of

• incubating a mixture comprising the sample, a PKA peptide substrate, a phosphorylation agent, and a reducing agent, the mixture having an oxidation reduction potential value that is less than −110 mV and greater than −20 mV, and
• detecting phosphorylated substrate formed in the incubated mixture.

A method for determining the activity of extracellular cyclic AMP dependent protein kinase A (PKA) in a sample derived from a bodily fluid and previously unfrozen for the phosphorylation of the PKA substrate, the method comprising the steps of

• incubating a mixture comprising the sample, a PKA peptide substrate, a phosphorylation agent, and a reducing agent, the mixture having an oxidation reduction potential value that is between −20 mV and 200 mV, and
• detecting phosphorylated substrate formed in the incubated mixture.

A kit for the assay of PKA activity comprising a PKA substrate, a phosphorylation agent, a control PKA of known activity and an oxidizing agent or a phosphatase inhibitor.