Neutrophil: A mobile fertilizer

Reuniting philosophy and science to advance cancer research

Cancers rely on multiple, heterogeneous processes at different scales, pertaining to many biomedical fields. Therefore, understanding cancer is necessarily an interdisciplinary task that requires placing specialised experimental and clinical research into a broader conceptual, theoretical, and methodological framework. Without such a framework, oncology will collect piecemeal results, with scant dialogue between the different scientific communities studying cancer. We argue that one important way forward in service of a more successful dialogue is through greater integration of applied sciences (experimental and clinical) with conceptual and theoretical approaches, informed by philosophical methods. By way of illustration, we explore six central themes: (i) the role of mutations in cancer; (ii) the clonal evolution of cancer cells; (iii) the relationship between cancer and multicellularity; (iv) the tumour microenvironment; (v) the immune system; and (vi) stem cells. In each case, we examine open questions in the scientific literature through a philosophical methodology and show the benefit of such a synergy for the scientific and medical understanding of cancer.

Risk surveillance and mitigation: autoantibodies as triggers and inhibitors of severe reactions to SARS-CoV-2 infection

COVID-19 clinical presentation differs considerably between individuals, ranging from asymptomatic, mild/moderate and severe disease which in some cases are fatal or result in long-term effects. Identifying immune mechanisms behind severe disease development informs screening strategies to predict who are at greater risk of developing life-threatening complications. However, to date clear prognostic indicators of individual risk of severe or long COVID remain elusive. Autoantibodies recognize a range of self-antigens and upon antigen recognition and binding, important processes involved in inflammation, pathogen defence and coagulation are modified. Recent studies report a significantly higher prevalence of autoantibodies that target immunomodulatory proteins including cytokines, chemokines, complement components, and cell surface proteins in COVID-19 patients experiencing severe disease compared to those who experience mild or asymptomatic infections. Here we discuss the diverse impacts of autoantibodies on immune processes and associations with severe COVID-19 disease.

Host Cxcr2-Dependent Regulation of Pancreatic Cancer Growth, Angiogenesis, and Metastasis

Pancreatic ductal adenocarcinoma (PDAC) manifests aggressive tumor growth and early metastasis. Crucial steps in tumor growth and metastasis are survival, angiogenesis, invasion, and immunosuppression. Our prior research showed that chemokine CXC- receptor-2 (CXCR2) is expressed on endothelial cells, innate immune cells, and fibroblasts, and regulates angiogenesis and immune responses. Here, we examined whether tumor angiogenesis, growth, and metastasis of CXCR2 ligands expressing PDAC cells are regulated in vivo by a host CXCR2-dependent mechanism. C57BL6 Cxcr2-/- mice were generated following crosses between Cxcr2-/+ female and Cxcr2-/- male. Cxcr2 ligands expressing Kirsten rat sarcoma (KRAS-PDAC) cells were orthotopically implanted in the pancreas of wild-type or Cxcr2-/- C57BL6 mice. No significant difference in PDAC tumor growth was observed. Host Cxcr2 loss led to an inhibition in microvessel density in PDAC tumors. Interestingly, an enhanced spontaneous and experimental liver metastasis was observed in Cxcr2-/- mice compared with wild-type mice. Increased metastasis in Cxcr2-/- mice was associated with an increase in extramedullary hematopoiesis and expansion of neutrophils and immature myeloid precursor cells in the spleen of tumor-bearing mice. These data suggest a dynamic role of host CXCR2 axis in regulating tumor immune suppression, tumor growth, and metastasis.

PHENOTYPIC HETEROGENEITY OF NEUTROPHILS: NEW ANTIMICROBIC CHARACTERISTICS AND DIAGNOSTIC TECHNOLOGIES

Introduction. Neutrophils are the most numerous subpopulation of leukocytes circulating in the blood; they constitute the first line of defence of the innate link of the immune system.

Aim. To generalize basic concepts about phenotypic and functional heterogeneity of neutrophils.

General findings. According to contemporary concepts, this type of blood cells performs not only antimicrobial functions, but also participates in capture and destruction of various microorganisms, including such processes as phagocytosis and intracellular degradation, degranulation and formation of extracellular neutrophilic traps after the detection of microorganisms. Neutrophils are considered to be a phenotypically heterogeneous pool of blood cells featuring a significant functional variability. Under pathological conditions, they can differentiate into discrete subpopulations with va rious phenotypic and functional characteristics. They are capable of interaction with macrophages, natural killers, dendritic and mesenchymal stem cells, B and T lymphocytes or platelets. In addition, neutrophils exhibit vector properties with respect to cancerous tumours. They possess a high morphological and functional variability, being modulators of both inflammation and active triggers of immune responses. A search for molecular markers able to efficiently differentiate neutrophil phenotypes and establish the degree of their diagnostic specificity for various pathologies is of a particular importance.