The role of the soluble CD30 serum level in colorectal cancer: a possible marker for a patient subset which could benefit from IL-2 biotherapy.

On the basis of our previous data suggesting an impairment in host immune response in colorectal cancer caused by an inappropriate switch from TH1 towards TH2 cells, we investigated the role of the soluble CD30 (sCD30) in this disease, as this molecule was found related to immune responses characterized by the activation of a prevalence of TH2 cells. We studied a group of healthy subjects and colorectal cancer patients determining the sCD30 serum level and the following immunological parameters: s interleukin-2 receptor (sIL-2R), IL-2, interferon (IFN) gamma, IL-6, IL-4 and IL-10 levels in the serum and peripheral blood mononuclear cell (PBMC) production; PBMC proliferative responses to IL-2, anti-CD3 monoclonal antibody (CD3) and IL-2 + CD3. Our overall data indicate that in colorectal cancer the sCD30 serum level is also linked to a prevalence of the TH2 immune response activation. However, the Multivariate statistical study underlines that the sCD30 level is principally related to the IL-6 TH2 cytokine. Moreover, it suggests that in colorectal cancer, the sCD30 level might be a marker for identifying a patient subset in which IL-2 biotherapy treatment could contribute to the restoration of the impaired immune system.