Endocrine effects of granulocyte colony-stimulating factor in cancer patients

Aims and background In addition to well-documented endocrine properties of interleukins, hemopoietic growth factors could also exert hormonal activities. In fact, our previous studies have shown that GM-CSF may stimulate cortisol and GH release. In contrast, few data only are available about the possible effects of G-CSF. This study was carried out to investigate endocrine effects of G-CSF in cancer patients. Methods The study included 8 cancer patients who were investigated after G-CSF (0.3 mg subcutaneously) or during saline infusion alone as control by collecting venous samples at zero time and after 2, 4, 6 and 8 h. Serum levels of cortisol, GH, PRL, FSH. LH, TSH and melatonin were measured by the RIA method. Results The circadian rhythm of cortisol was not influenced by G-CSF. No significant differences in mean levels of GH, PRL, FSH or LH were seen after G-CSF and during saline infusion. Both TSH and melatonin decreased after G-CSF, without, however, significant differences with respect to the values seen on saline alone. Conclusions The study showed that G-CSF has no substantial endocrine affects in humans. Therefore, G-CSF would differ from GM-CSF not only for its hemopoietic properties, but also from an endocrine point of view.