Abstract

For a long time markers that can detect a malignant cell transformation as early as possible have been sought. Substances which have been discovered are known as tumor markers. Stem cell factor (SCF) and interleukin 3 (IL-3) are members of a group of glycoprotein growth factors called hematopoietic cytokines (HCs). These factors take part in the regulation of developmental processes of hematopoietic progenitor cells and it was proved that HCs can be produced by different cancer cells, including colorectal cancer. The aim of this study was to investigate a potential role for SCF and IL-3 as tumor markers for colorectal cancer. We compared the serum levels of SCF and IL-3 in colorectal cancer patients with those in healthy subjects (control group) and commonly accepted tumor markers, such as carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA 19-9). We defined the diagnostic sensitivity, specificity, positive predictive value, negative predictive value, and receiver-operating characteristics (ROC) curve of tested substances. SCF and IL-3 were determined using enzyme-linked immunosorbent assay (ELISA). CEA and CA 19-9 were measured by microparticle enzyme immunoassay. The serum levels of HCs and tumor markers were investigated in 75 patients with colorectal cancer and in 40 healthy subjects. There were significant differences in the level of circulating SCF and IL-3 in the colorectal cancer patients compared to the control group. Moreover, the diagnostic sensitivity of SCF was higher than the sensitivity of CEA and CA 19-9. The SCF area under the ROC curve was larger than the IL-3 area but smaller than the CEA and CA 19-9 areas. The diagnostic specificities of cytokines were lower than those of tumor markers, but the combined use of cytokines and tumor markers increased the diagnostic values. The highest values of diagnostic parameters were observed for the combined use of SCF and CA 19-9. These results suggest a potential role for SCF and IL-3 as tumor markers for colorectal cancer, especially in combination with CEA or CA 19-9.