decreased serum level of interleukin-19 in iranian patients with breast cancer

background: interleukin-19, a member of the interleukin-10 family of cytokines, contributes to breast cancer pathogenesis. high interleukin-19 expression in breast tumor tissues is associated with poor clinical outcome. this study aimed to assess the changes in serum level of interleukin-19 in breast cancer patients in comparison with normal women and its association with the clinicopathological parameters of this disease. methods: enzyme-linked  immunosorbent  assay was used  to  analyze  serum levels of interleukin-19 in 116 women with breast cancer before chemotherapy or radiotherapy, and in 60 healthy age-matched women without any acute or chronic diseases or family history of cancer. results: there were significantly lower serum interleukin-19 levels in breast cancer patients  (median:  27.3  pg/ml;  range:  10.5-2443.6 pg/ml)  compared  to healthy controls (median: 35.1 pg/ml; range: 10.9-13676.6 pg/ml; p<0.01). compared to the healthy control group, the decrease in serum interleukin-19 concentration was seen in all breast cancer stages. however the decrease was only significant for stage iii (p=0.02). we found no significant association between serum interleukin-19 levels and stage, grade, lymph node involvement or other clinicopathological variables of the  disease. however, when  compared  to  the  healthy  control  group, we  found significantly decreased serum interleukin-19 levels in patients with involved lymph nodes (p<0.01) or tumor size greater than 2 cm (p=0.01). conclusion: there were significantly decreased interleukin-19 levels in breast cancer patients compared to the healthy control group. we observed no association between serum interleukin-19 levels and clinicopathological parameters in breast cancer patients.