IL-6/IL-10 mRNA expression ratio in tumor tissues predicts prognosis in gastric cancer patients without distant metastasis.

There was growing evidence that inflammatory responses played significant roles in malignancies. However, the impact of pro-inflammatory-to-anti-inflammatory factor ratio in tumor tissues has not been investigated in gastric cancer (GC) yet. We collected patient data from The Cancer Genome Atlas (TCGA) database. A total of 270 stomach adenocarcinoma (STAD) patients without distant metastasis were included in the study. After screening 12 candidate pro-inflammatory-to-anti-inflammatory pairs, only the IL-6/IL-10 mRNA expression ratio in tumor tissues had a significant effect on overall survival (OS) of STAD patients (P = 0.014). X-tile analysis showed that the greatest survival differences were obtained when the cutoff value of IL-6/IL-10 mRNA expression ratio was set at 1.3 and 5.5. With the low-ratio group (IL-6/IL-10 mRNA expression ratio: < 1.3) as reference, OS time for both the medium-ratio group (IL-6/IL-10 mRNA expression ratio: 1.3-5.5) and the high-ratio group (IL-6/IL-10 mRNA expression ratio: > 5.5) was significantly shorter (P < 0.05). Multivariate Cox regression analyses indicated that IL-6/IL-10 mRNA expression ratio was an independent prognostic factor for OS and disease-specific survival (DSS). These findings provided a novel and powerful tool for a more rational management of GC patients.