Abstract: The present invention relates to the use as a biomarker of the active form of a human caspase protein, preferably the human caspase-4 or caspase-1, or of the active form of the protein encoded by an orthologue gene of the human caspase protein, preferably by an orthologue gene of the human caspase-4, for example the murine caspase-11 protein, in a method of diagnosis and/or prognosis and/or of monitoring the progression of a tumor, particularly lung cancer.