The Interleukin-8-CXCR1/2 Axis as a Therapeutic Target in Peritoneal Carcinomatosis

Peritoneal carcinomatosis (PC) is a late-stage manifestation of abdominopelvic malignancies with poor prognosis and limited treatment options. Unique biochemical mechanisms within the peritoneal cavity play a key role in disease progression and resistance to therapy. Despite current therapies like systemic chemotherapy and cytoreductive surgery, patients frequently develop severe complications, including bowel obstruction, nutritional decline, and ascites, driving the need to address the pro-tumorigenic niche in the peritoneal cavity. The immune microenvironment in PC is marked by elevated proinflammatory mediators, such as IL-6 and IL-8, which skew the response toward innate rather than adaptive immune responses. IL-8 signaling, through its receptors CXCR1 and CXCR2, promotes neutrophil recruitment, chronic inflammation, angiogenesis, epithelial-mesenchymal transition, and immune evasion, making the IL-8/CXCR1/CXCR2 axis a potential therapeutic target in PC. Pre-clinical models provide evidence that IL-8 or CXCR1/CXCR2 blockade may be a valuable therapeutic strategy. IL-8 targeting agents such as monoclonal antibodies (BMS-986253) and small-molecule inhibitors (SX-682, AZD5069, navarixin) have shown efficacy in mitigating tumor growth and improving the efficacy of immune checkpoint inhibitors. Phase I and II trials have demonstrated encouraging safety profiles and preliminary efficacy when treating multiple abdominopelvic malignancies. In this review, we discuss the influence of the IL-8/CXCR1/CXCR2 axis within the peritoneal immune environment in PC and highlight recent work using IL-8 or CXCR1/CXCR2 blockade as a therapeutic strategy for PC. Continued research into the peritoneal immune microenvironment and the development of targeted therapies are essential for improving the management and prognosis of PC, potentially enhancing antitumor immunity and patient outcomes.