ORIGINAL RESEARCH article

Front. Immunol.

Sec. Cancer Immunity and Immunotherapy

Volume 16 - 2025 | doi: 10.3389/fimmu.2025.1569042

This article is part of the Research TopicImmune Checkpoints Regulatory Mechanisms and Immunotherapy Strategies in Gastrointestinal TumorsView all 8 articles

IL-6 is a prognostic biomarker in patients with advanced esophageal squamous cell carcinoma received with PD-1 inhibitors

Provisionally accepted
Ping  HuangPing HuangManyi  ZhaoManyi ZhaoJianhong  XiaJianhong XiaHongliang  LiHongliang LiJunxia  SunJunxia SunXin  LiXin LiChunsheng  YangChunsheng YangGuangyi  GaoGuangyi GaoWenhang  ZhouWenhang ZhouMeifeng  ZhongMeifeng ZhongHongmei  YongHongmei Yong*
  • Affiliated Huai’an Hospital of Xuzhou Medical University, Xuzhou, China

The final, formatted version of the article will be published soon.

Background: Due to the low efficacy rates, effective biomarkers are desperately needed to determine populations of advanced esophageal squamous cell carcinoma (ESCC) that may benefit from immune checkpoint inhibitor (ICI) treatment.To explore the relationship between IL-6 and the esophageal cancer tumor immune microenvironment using online databases and esophageal cancer tissue microarrays and to investigate the predictive role of IL-6 for immunotherapy in esophageal squamous carcinoma patients through clinical study data. Methods: RNAseq datasets of ESCC patients were obtained from TCGA, and the relationship between IL-6 and immune cells was discovered using TIMER 2.0 databases. CD8, IL-6, and PD-L1 expression in ESCC tissue microarrays were measured using immunohistochemistry, and then the tumor microenvironment was classified.Furthermore, blood specimens were collected from advanced ESCC patients before they received PD-1 inhibitors, and follow-up was conducted to gather clinical survival data. Based on IL-6 levels. We divided the population into the high and low IL-6 groups, comparing the efficacy and survival of the two groups. Results: IL-6 positively correlated with mRNA levels of PD-L1, negatively correlated with immune cells, and positively correlated with immunosuppressive cells. High IL-6 expression in tissues might make PD-1/L1 blockade therapy less effective. Individuals with higher baseline plasma IL-6 levels had significantly lower objective remission rates and inferior PFS and OS. Elevated baseline IL-6 was demonstrated to be an independent risk factor for the prognosis of advanced ESCC patients using PD-1 inhibitors, according to COX regression analysis. Conclusion: IL-6 overexpression correlates with the immunosuppressive tumor microenvironment in ESCC, and it can be a predictive biomarker in ESCC patients received with PD-1 inhibitors.

Keywords: esophageal squamous cell carcinoma, IL-6, PD-1 inhibitor, Tumor Microenvironment, prognosis Other notes about the manuscript:

Received: 31 Jan 2025; Accepted: 23 Apr 2025.

Copyright: © 2025 Huang, Zhao, Xia, Li, Sun, Li, Yang, Gao, Zhou, Zhong and Yong. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

* Correspondence: Hongmei Yong, Affiliated Huai’an Hospital of Xuzhou Medical University, Xuzhou, China

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