Introduction. Since colorectal cancer (CRC) is the second most commonly diagnosed malignancy in Europe and third worldwide, novel biomarkers for diagnosing the disease are critically needed. Objectives. According to our knowledge, the present study is the first to evaluate the clinical usefulness of serum CXCL-8 (C-X-C motif chemokine 8) in the diagnosis and progression of CRC compared to classical tumor marker CEA (carcinoembryonic antigen) and marker of inflammation CRP (C-reactive protein). Patients and Methods. The study included 59 CRC patients and 46 healthy volunteers. Serum levels of selected proteins were measured using ELISA (enzyme-linked immunosorbent assay), CMIA (chemiluminescent microparticle immunoassay), and immunoturbidimetric methods. Results. Serum concentrations of CXCL-8, similarly to those of the classical tumor marker CEA and inflammatory state marker CRP, were significantly higher in CRC patients than in healthy controls. There were statistically significant differences in CXCL-8 concentrations between tumor stages, as established by the Kruskal–Wallis test and confirmed by the post hoc Dwass–Steele–Critchlow–Fligner test. CXCL-8 levels were also significantly elevated in CRC patients with distant metastases compared to patients in the subgroup without metastases. Diagnostic sensitivity, predictive values for negative results (NPV), and AUC (area under the Receiver Operating Characteristic Curve—ROC curve) of CXCL-8 were higher than those of CEA, while diagnostic specificity and predictive values for positive results (PPV) of CXCL-8 were higher than those of CRP. Conclusions. Our findings indicate greater utility of CXCL-8 in comparison to the classical tumor marker CEA in the diagnosis of CRC. Moreover, serum CXCL-8 might be a potential biomarker of colorectal cancer progression.

C-X-C motif chemokine 8 (CXCL-8), known as interleukin-8, is a pro-inflammatory cytokine which acts as a chemotactic factor, mainly for leukocytes. CXCL-8 is produced by malignant cells, and therefore it can stimulate the growth and progression of various neoplasms, including oesophageal cancer (OC). The aim of the current study was to measure serum concentrations of chemokine CXCL-8 in OC patients and establish whether this protein might be considered a potential candidate for a tumor marker in the diagnosis and progression of OC. The study included 50 OC subjects (32 patients with squamous cell carcinoma of oesophagus—OSCC, 18 patients with adenocarcinoma—OAC) and 26 healthy volunteers. Serum CXCL-8 concentrations were measured using immunoenzymatic assay (ELISA). CRP levels were determined by immunoturbidimetric method, while classical tumor marker levels were measured using chemiluminescent immunoassay. CXCL-8 concentrations were significantly higher in OC patients compared to healthy controls. We demonstrated significant differences between CXCL-8 concentrations and depth of tumor invasion (T factor) in OC patients and OSCC subgroup. In addition, CXCL-8 levels were found to correlate positively with T factor and CRP concentrations. The diagnostic sensitivity, negative predictive value and the area under ROC curve (AUC) of CXCL-8 were higher than those of classical tumor markers. Our findings suggest the potential usefulness of CXCL-8 in the diagnosis and progression of OC. However, due to the non-specific nature of this chemokine, further research is needed to clarify the usefulness of CXCL-8 as a tumor marker of OC.

Every year, almost 2 million people develop colorectal cancer (CRC), which makes it the fourth most common malignancy worldwide. It is also estimated that approximately 48% of CRC patients will die from the disease. Thus, noninvasive and accurate methods for early detection and prevention of CRC are sorely needed. It is suggested that C-X-C motif ligand 1 (CXCL1) and C-X-C motif ligand 8 (CXCL8) as well as their cognate receptors can mediate tumor growth, proliferation, survival, neoangiogenesis and metastasis of malignant cells, including CRC. However, little is known about the clinical significance of these proteins as potential biomarkers for CRC. Therefore, in our review, we performed a comprehensive literature search using the PubMed database to identify original articles that investigated whether CXCL1 and CXCL8 and their receptors play a role in CRC pathogenesis. In summary, our review highlighted the potential significance of CXCL1/CXCR2 and CXCL8/CXCR1,-2 in the diagnosis and progression of CRC as well as indicated their potential therapeutic significance. However, given the non-specific nature of analyzed chemokines and a small number of studies concerning the assessment of blood concentration of these proteins in CRC patients, investigations need to be continued in the future before selected chemokines could be established as biomarkers for CRC.

Colorectal cancer (CRC) is one of the leading causes of cancer-related death. It is the second most frequently diagnosed malignancy in Europe and third worldwide. Colorectal malignancies diagnosed at an early stage offer a promising survival rate. However, advanced tumors often present distant metastases even after the complete resection of a primary tumor. Therefore, novel biomarkers of CRC are sorely needed in the diagnosis and prognosis of this common malignancy. A family of chemokines are composed of small, secreted proteins. They are best known for their ability to stimulate the migration of several cell types. Some investigations have indicated that chemokines are involved in cancer development, including CRC. This article presents current knowledge regarding chemokines and their specific receptors in CRC progression. Moreover, the prime aim of this review is to summarize the potential role of these proteins as biomarkers in the diagnosis and prognosis of CRC.

Background/Aim: The current study aimed to evaluate the clinical utility of the levels of the C-X-C-motif chemokine receptor-2 (CXCR-2) serum receptor in comparison to the carcinoembryonic antigen (CEA) tumor marker and -the C-reactive protein (CRP) inflammatory marker in the diagnosis and prognosis of colorectal cancer (CRC). Materials and Methods: Our study comprised 59 patients with CRC and 46 healthy subjects. Serum concentrations of the analyzed proteins were measured using enzyme-linked immunosorbent assay, chemiluminescent microparticle immunoassay and immunoturbidimetric methods. Results: Serum levels of CXCR-2 were lower, while those of CEA and CRP were significantly higher in CRC patients in comparison to the control group. The diagnostic sensitivity of CXCR-2 was higher than that of CEA, and increased when CXCR-2 analysis was combined with CEA or CRP. Conclusion: According to our knowledge, this is the first study concerning the significance of CXCR2 as a CRC biomarker. Measurement of the serum levels of CXCR-2 may improve the diagnosis efficiency of CRC patients, especially in combination with the tumor marker CEA.