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.

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.

Colorectal cancer (CRC) is among the most common malignancies worldwide. CRC is considered a heterogeneous disease due to various clinical symptoms, biological behaviours, and a variety of mutations. A number of studies demonstrate that as many as 50% of CRC patients have distant metastases at the time of diagnosis. However, despite the fact that social and medical awareness of CRC has increased in recent years and screening programmes have expanded, there is still an urgent need to find new diagnostic tools for early detection of CRC. The effectiveness of the currently used classical tumour markers in CRC diagnostics is very limited. Therefore, new proteins that play an important role in the formation and progression of CRC are being sought. A number of recent studies show the potential significance of granzymes (GZMs) in carcinogenesis. These proteins are released by cytotoxic lymphocytes, which protect the body against viral infection as well specific signalling pathways that ultimately lead to cell death. Some studies suggest a link between GZMs, particularly the expression of Granzyme A, and inflammation. This paper summarises the role of GZMs in CRC pathogenesis through their involvement in the inflammatory process. Therefore, it seems that GZMs could become the focus of research into new CRC biomarkers.

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.

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.

The aim of this study is to assess the synthesis of kappa (κ) and lambda (λ) free light chains (FLCs) in the serum of patients with COVID-19. All the 120 serum samples were collected from patients with COVID-19 and from healthy controls (vaccinated and non-vaccinated against SARS-CoV-2). FLCs, IgG total, IgG4, IgG anti-Nucleocapsid (N), anti-spike S1 receptor binding domain (S-RBD) antibodies and IL-6 were measured according to the manufacturers’ instructions. The concentrations of anti-N IgG, IgG total, IgG4 and IL-6 were elevated in the COVID-19 group in comparison to the vaccinated and non-vaccinated controls. The levels of anti-S-RBD IgG and κFLC were increased in COVID-19 and healthy vaccinated patients when compared to non-vaccinated controls. λFLC concentration was higher in the COVID-19 group than in the non-vaccinated group. The κ:λ ratio was lower in both COVID-19 and non-vaccinated groups in comparison to vaccinated controls. κFLC correlated with all tested parameters (anti-S-RBD IgG, anti-N IgG, λFLC, κ:λ ratio, IgG total, IgG4 and IL-6) except CRP, whereas λFLC correlated with all examined parameters except IgG4. Elevated levels of FLCs in COVID-19 and healthy vaccinated against SARS-CoV-2 patients, as well as the correlation between free light chains with specific anti-SARS-CoV-2 antibodies and IL-6, reflect hyperactivation of the immune system after contact with coronavirus. Furthermore, it seems that serum levels of FLCs might be used as predictive markers of COVID-19. Our findings suggest that free light chains are involved in SARS-CoV-2 infection. However, understanding the exact mechanism requires further investigation.