Introduction. Pancreatic Cancer (PC) is one of the biggest challenges in today's oncology. Based on WHO GLOBOCAN 2020 estimates, pancreatic cancer has ranked the 11th most common cancer in the world counting 495 773 new cases and causing 466 003 deaths. PC is 7th leading cause of cancer-related deaths worldwide [1]. PC is currently treated with a combination of surgery, chemotherapy and radiation therapy in selected cases which results in long-term survival only in a small percentage of patients. Cancer therapies that incorporate immunotherapy-based techniques have become increasingly common in recent years. IL-1b and IL-4 are members of the cytokine family, with a pivotal role in the activation and regulation of immune response and progression of cancer. Tumor cell-derived IL-1b promotes pancreatic tumor proliferation, immune suppression, neoangiogenesis [2]. However, IL-1b, produced by M1 macrophages, have antitumoral properties and help to activate cytotoxic T cells, which can induce cancer cell death [3]. IL-4, produced by regulatory T Cells, induce differentiation of monocytes into M2 macrophages, which exhibit tumor-promoting capabilities involving immuno-suppression, angiogenesis, metastasis [4]. M1/M2 ratio are known to correlate with patients' longevity, higher level of M2 associating with poor prognosis [5].
Aim. The purpose of this research was to study if and how differed IL-1b and IL-4 levels in sera of cancer patients compared with healthy control.
Materials and methods. Main material of this study was sera from pancreatic cancer (PC) patients - 11 subjects and 15 healthy donors (HC). Blood from 3ml vacutainers with SST (serum clot activator) were left at room temperature for one hour before centrifugation at 2500g in 4°C 20min. After centrifugation first layer before gel was sera. We collected 2ml sera into krio tubes, stored it in -80°C temperature until bead-based multiplex assay. On the day of assay all previously frozen sera samples were centrifuged at 16000g 4°C 4min and diluted according to the manufacturer's protocol for Human Premixed Multi-Analyte Kit (Luminex). 96well plate with target antibodies for IL1b and IL4 cytokines was read using a Luminex 100 analyzer. Statistical analysis was performed using GraphPad (version 9.01; GraphPad Software Inc., La Jolla, CA, USA) software. The data are presented as medians with MIN/MAX values from 26 subjects grouped to PC and HC. Nonparametric Mann–Whitney test was used for comparison of concentration levels between groups. Statistical significance was defined as p<0.05. Correlation was calculated by Spearman method.
Results. IL-1b and IL-4 concentrations in sera were increased in pancreatic cancer patients' group vs healthy control. Only IL-1b data was statistically significant (p<0.05). Correlation data showed weak positive association between IL-1b and IL-4 concentration (by Spearman coef.).
Conclusions. The increase of IL-1b and IL-4 in sera of pancreatic cancer patients might be associated with enhanced production of these cytokines in the tumor microenvironment and tumor-associated macrophages (TAMs). Free cytokine burst in cancer patients' sera showed us fight between pro-inflammatory and anti-inflammatory responses.