Serum levels of G-CSF and IL-7 in Iranian breast cancer patients.

Breast cancer cells and tumor stroma produce different cytokines and soluble factors. Cytokines, while playing crucial roles in immune responses to tumors, also favour tumor growth and progression. IL-7 and G-CSF are two cytokines that may exert influences on the pathophysiology of breast cancer. Sera were collected from 136 females with breast cancer before receiving chemotherapy or radiotherapy. The control group comprised of 60 healthy age-matched females without any acute or chronic diseases with no family history of breast cancer. Serum levels of IL-7 and G-CSF were measured by commercial enzyme linked immunosorbent assay. While there was no significant difference in the level of G-CSF between patients (92.81 ± 594.54 pg/ml) and controls (0.00 pg/ml), G-CSF level in sera of patients with advanced stages of breast cancer was elevated compared to early stages (p=0.0001). Moreover, the highest level of G-CSF was seen in patients with N3 phase tumors (p=0.0001). IL-7 was slightly but not significantly higher in the control group (0.04 ± 0.11 pg/ml) in comparison with patients (0.02 ± 0.10 pg/ml). Interestingly, a significant increase in the level of IL-7 in patients with skin involvement was observed (p=0.001). Our results showed an elevation of G-CSF in sera of patients with advanced stages of tumor, while IL-7 elevation correlated with skin involvement of breast cancer. IL-7 can be produced by keratinocytes in skin tissue and may be involved in the pathologic establishment of metastatic tumor cells in skin.