Hemostatic System in Malignancy: Providing the “Soil” in Metastatic Niche Formation

Malignancy arises and progresses in tight association with changes in the tumor microenvironment and deregulation of hemostatic system. Cancer induces hemostatic imbalance through production and secretion of procoagulant substances, suppression of anticoagulant mechanisms, endothelial activation, and angiogenic switch. Cancer cells are equipped with certain coagulation signaling receptors such as tissue factor (TF) and urokinase plasminogen activator receptor (uPAR). Tissue factor: as major initiator of coagulation, TF is considered the main cause for hypercoagulability in cancer. Constitutive TF expression by cancer cells is a hallmark of malignancy rendering tumors proangiogenic and prometastatic. TF fosters metastasis through coagulation-dependent pathways leading to fibrin deposition in the evolving premetastatic niche. TF has been identified as an independent predictor for metastatic development and adverse prognosis. uPAR: Tissue overexpression of uPAR is demonstrated in almost all human cancers and is associated with advanced disease. Increased uPAR expression is driven by molecular events involving K-ras and SRC oncogenes. Transactivation of these receptors, mediated by binding to hemostatic proteins, activates intracellular signaling pathways, modulates gene expression and facilitates processes of tumor initiation, epithelial-to-mesenchymal transition, anoikis, and metastasis. By manipulating hemostatic processes, tumor induces tolerant host environment necessary for evasion of defense attacks, survival, and progression

Assessment of clinical utility and predictive potential of pre-chemotherapy soluble urokinase plasminogen activator receptor: Observational single center study

Alteration of urokinase plasminogen activator receptor (uPAR) in neoplasms is a prerequisite for invasiveness and metastatic ability. In the present study, we aimed to evaluate the relationship of pre-chemotherapy soluble uPAR (suPAR) with the odds for metastasis, lack of disease control, and its predictive ability for progression-free survival (PFS). Baseline plasma suPAR levels were measured by ELISA in 89 patients with various cancers prior to initiation of systemic treatment. Patients were followed prospectively until metastatic progression or death. TCGA Pan-Cancer dataset was mined for available RNAseq expression data of the PLAUR gene in patients with breast, colon, and lung cancer, and therelevant genomic and clinical data were extracted for further analysis. Pre-chemotherapy suPAR levels were significantly associated with white blood cell counts and fibrinogen and were significantly elevated both in patients with metastatic disease and in patients with progression. Increasing suPAR was significantly associated with odds for progression in the prespecified multivariate analysis (odds ratio 2.47, 95% confidence interval 1.3 – 5.11). In univariate Cox regression, suPAR was predictive of shortened progression-free survival (PFS) (hazard ratio 1.065, 95% confidence interval 1.002 – 1.13; p = 0.041). There was a trend towards shortened PFS in patients with higher baseline suPAR levels (cutoff 8.1 ng/mL). In the TCGA lung cancer cohort, PLAUR mRNA expression was significantly associated with shortened PFS in both univariate and multivariate analyses. High PLAUR gene expression conferred significant survival disadvantage only in patients with colon and lung cancer. SuPAR may bear predictive potential for adverse outcomes in cancer, but its utility as a biomarker seems to be more pronounced in cancers with associated inflammatory state

Autoimmune Phenomena in Patients with Solid Tumors

Introduction: Autoimmune disorders have been documented in solid tumors and malignant hematological disorders. They are very common and well studied in lymphomas which are associated with immune imbalance. They are less common in solid tumors and are categorized as paraneoplastic syndromes with unclear pathogenesis