Background: This study evaluated long non-coding RNA ANRIL expression in peripheral blood leukocytes of patients with breast cancer and its diagnostic value in relation to oxidative stress and inflammation.
Methods: This case–control study included 29 newly diagnosed patients with breast cancer and 30 healthy controls. ANRIL expression was quantified by quantitative real-time polymerase chain reaction. Malondialdehyde, total antioxidant capacity, superoxide dismutase, and plasma interleukin-6 were measured using commercial assays. Diagnostic performance was assessed by receiver operating characteristic analysis. The Cancer Genome Atlas Breast Invasive Carcinoma data were analyzed for differential expression, co-expression, oxidative stress-related gene correlations, and functional enrichment.
Results: ANRIL expression showed a decreasing trend in patients with breast cancer versus controls (P = 0.05). Patients had higher malondialdehyde and interleukin-6 levels and lower total antioxidant capacity and superoxide dismutase activity (all P < 0.001). No significant correlations were observed between ANRIL and oxidative stress markers or plasma interleukin-6. Receiver operating characteristic analysis showed good discrimination by ANRIL (area under the curve = 0.864). In The Cancer Genome Atlas Breast Invasive Carcinoma data, ANRIL and interleukin-6 showed a weak but significant inverse correlation (r = −0.114, P < 0.001). Functional enrichment indicated that ANRIL-associated genes were mainly involved in cell-cycle regulation and mitosis.
Conclusions: ANRIL showed a decreasing trend and good discriminatory performance in breast cancer. Although no direct association was observed with the assessed oxidative stress or inflammatory markers, transcriptomic analysis linked ANRIL to cell-cycle- and mitosis-related pathways. Larger multicenter and mechanistic studies are needed to validate these findings.