The role of cytokines as diagnostic biomarkers and therapeutic modulators in cancer management

Cytokines are small signaling proteins that regulate immune responses, inflammation, and cellular communication, playing a critical role in cancer monitoring and treatment response. They can activate or suppress the immune system; thus, they exert both pro-inflammatory and anti-inflammatory effects in disease regulation. However, dysregulation, manifested as altered levels in biological fluids or tissues, is strongly associated with tumor progression, poor prognosis, therapeutic response, and immune restoration. The aim of this study is to evaluate cytokines as diagnostic biomarkers and therapeutic modulators in cancer management, with a focus on their role as indicators of cancer status and treatment response. This comprehensive literature review was conducted using original research articles, reviews, systematic literature reviews, and meta-analyses published between 2020 and 2026 from multiple electronic databases by using “biomarkers” “interleukin,” “immunotherapy,” and “cytokine” as keywords. The findings indicate that high levels of cytokines, particularly interleukins such as IL-6, IL-8, IL-10, IL-22, and IL-35, are significantly associated with tumor progression, poor prognosis, and therapeutic response across various cancer types. Elevated cytokine levels in biofluids, including blood and cerebrospinal fluid, support their use as minimally invasive biomarkers for early detection and disease monitoring. In conclusion, the findings demonstrate that cytokine level biomarkers are associated with tumor progression, poor prognosis, and therapeutic modulation in different types of cancer. However, their dual role provides significant potential for advancing precision oncology and improving patient outcomes.