Serum Cytokine Profiles Associated with Inflammation and Tumor Progression in Crohn’s Disease and Colorectal Cancer

Chronic inflammation is a recognized driver of colorectal cancer (CRC) development, particularly in patients with Crohn's disease (CD). This study aimed to explore serum inflammatory cytokine profiles in patients with Crohn's disease and colorectal cancer and to assess their associations with disease activity and tumor-related features. Seventy-eight participants were included: 24 with CD, 31 with CRC, and 23 healthy controls. Serum levels of 27 cytokines were measured using the Bio-Plex Pro Human Cytokine 27-plex Assay. Principal component analysis identified three cytokine clusters (factors). Factor 2, comprising IL-9, MIP-1β, and PDGF-β, was significantly elevated in CD patients compared to controls (<i>p</i> < 0.001), showed intermediate levels in CRC patients, and positively correlated with fecal calprotectin (R = 0.44; <i>p</i> = 0.04), indicating an association with local intestinal inflammation. In CRC patients, Factor 1, comprising key Th1/Th17 cytokines (IL-1β, IL-2, IL-4, IL-5, IL-15, IL-17A, FGF-B, GM-CSF, IFN-γ, TNF-α, and VEGF), reflecting pro-inflammatory and cell-mediated immune signaling, correlated with lymph node metastasis (τ = 0.27; <i>p</i> = 0.03), while Factor 2 showed a trend toward a negative correlation with tumor histological grade (τ = -0.22; <i>p</i> = 0.09). Factor 3, encompassing regulatory and hematopoietic cytokines, did not differ significantly between groups (<i>p</i> = 0.21). These findings suggest that IL-9, MIP-1β, and PDGF-β reflect inflammatory activity and may be involved in inflammation-associated tumorigenic processes in the gut. Serum profiling of selected cytokines may provide biologically relevant information and support further investigation of inflammation-associated immune patterns in CD and CRC. Further studies are warranted to validate their clinical utility and to elucidate their mechanistic role in inflammation-driven colorectal carcinogenesis.