Cytidine deaminase expression level in cancer as a new therapeutic target

An in vitro method for selecting a patient affected with a tumor for a treatment with an antitumor compound or for predicting the response of a patient affected with a tumor to a treatment with an antitumor compound, wherein the method comprises:

• (a) measuring the expression level of CDA (Cytidine Deaminase) in a cancer sample from said patient,
• (b) comparing the CDA expression level of the cancer sample to a reference expression level, wherein a CDA expression level of the cancer sample lower than the reference expression level is predictive of the efficacy of a treatment with an antitumor compound selected from the group consisting of the compounds of table 4, and/or wherein a CDA expression level of the cancer sample higher than the reference expression level is predictive of the efficacy of a treatment with an antitumor compound selected from the group consisting of the compounds of table 3,
• (c) optionally, selecting patients with CDA expression level of their cancer sample lower than the reference expression level as suitable for a treatment with an antitumor compound selected from the group consisting of the compounds of table 4 and/or selecting patients with CDA expression level of their cancer sample higher than the reference expression level for a treatment with an antitumor compound selected from the group consisting of the compounds of table 3.