Biochemical profile of Bence-Jones type multiple myeloma.

Multiple myeloma (MM) is a malignant tumor occurring from plasma cells that produce an abnormal monoclonal immunoglobulin - a paraprotein. A distinctive feature of Bence-Jones myeloma is the excretion of monoclonal free light chains of immunoglobulins with 24h urine, and the absence of monoclonal intact immunoglobulins secretion. Comprehensive analysis of biochemical parameters in blood serum and 24h urine in patients with Bence-Jones multiple myeloma using electrophoretic and immunoturbidimetric methods to assess their sensitivity as biomarkers. 50 patients with a morphologically confirmed diagnosis of MM of the Bence-Jones immunochemical type were examined. 28 people without oncological diseases were examinedas a control. Detection of monoclonal secretion in blood serum and daily urine was performed by immunofixation electrophoresis on the Hydrasys 2 electrophoretic system (Sebia). The determination of free light chains of immunoglobulins (FLC) was performed by the immunoturbidimetric method (Binding Site) on an Advia 1800 analyzer (Siemens). Analysis of IgG, IgA, IgM, ß2-microglobulin and C-reactive protein was performed on Cobas 6000 analyzer (Roche). The median excretion of Bence-Jones protein in 24h urine of MM patients was 0.49 g/24h (0.06-2.45 g/24h). In the blood serum, in 86% of cases, the presence of paraproteinemia, represented by κ and λ type light chains of immunogloublins was detected. At the same time, the frequency of detection of monoclonal secretion in blood serum in Bence-Jones type λ myeloma was 95.7%, which was statistically significantly higher than the frequency of detection of monoclonal secretion of type κ - 77.8%. In patients with identified paraproteinemia, Bence-Jones protein excretion in daily urine (median 0.82 g/day) was statistically significantly higher than in patients without a monoclonal component detected in blood serum (median 0.04 g/24h). The levels of FLC in blood serum obtained by immunoturbidimetry in Bence-Jones myeloma of the corresponding type were higher than the reference levels in 100% of cases. The median level of κ-FLC reached 4358 mg/l, λ-FLC - 2225 mg/l, which was statistically significantly higher than the control levels. The median concentrations of IgG, IgA and IgM in patients with Bence-Jones myeloma were statistically significantly lower than in the control group, while the medians of ß2-microglobulin and C-reactive protein were significantly higher than in the control. Our investigation showed high diagnostic efficiency of electrophoretic and immunoturbidimetric analysis of monoclonal secretion in patients with Bence-Jones MM, while FLC analysis demonstrated maximum sensitivity. Bence-Jones MM revealed biochemical signs of secondary immunodeficiency and general inflammatory syndrome.

Chromogranin B in blood serum of patients with neuroendocrine tumors.

Neuroendocrine tumors (NETs) are a heterogeneous group of neoplasms from cells of the diffuse neuroendocrine system. Chromogranin B (CgB) is an acidic protein of the granin family, which can be used to detect the tumours of neuroendocrine nature. Analysis of levels and evaluation of the diagnostic efficiency of CgB in the blood serum of patients with NETs of various localizations. Patients with NETs (n=121) without specific treatment were examined. In the study were presented next localizations: 74 - pancreas, 20 - stomach, 12 - large intestine, 15 - other localizations (lungs, mammary gland, prostate gland, NETs with unidentified primary). 54 practically healthy donors were examined as control group. The determination of CgB in blood serum was performed with ELISA method on BEP 2000 analyzer using a standardized test system Human Chromogranin B (USCN, China). CgB levels in common NET group (median 18.9 ng/mL) were statistically significantly higher than in the control group (8.8 ng/mL). The highest median was obtained in group of intestinal NETs (21.2 ng/ml), which exceeded the median of the control group by more than 2.4 times. According to ROC analysis in the common NET group relative to the control group, the area under the curve AUC was 0.88 (95% CI 0.83-0.929). According to cut-off level of CgB - 15.8 ng/ml, the diagnostic sensitivity was 69.4%, with a specificity of 96.3%. The highest diagnostic sensitivity was in the group of the intestinal NETs (75.0%) and pancreas (71.2%). The study showed the significance of CgB as a potential biochemical marker of NETs with various localizations, alternative to CgA.

Pro-Gastrin-Releasing Peptide as a Marker of Small Cell Lung Cancer.

The serum levels of pro-gastrin-releasing peptide (proGRP), neuron-specific enolase (NSE), and chromogranin A (CgA) were studied in 69 patients with small cell lung cancer and 50 apparently healthy donors. A significant increase of all studied biochemical markers was revealed in small cell lung cancer patients, while the highest diagnostic efficiency was demonstrated by proGRP compared to NSE and CgA. ProGRP is a promising biochemical marker of small cell lung cancer, especially sensitive in patients with distant metastases (in the brain, liver, and bones).

Comparative analysis of the levels of soluble forms of receptor and ligand of the immunity control point PD-1/PD-L1 in the blood serum of patients with typical bone osteosarcoma and chondrosarcoma.

Results of ELISA investigation of the pretreatment sPD-1 and sPD-L1 content in blood serum of 133 bone neoplasms patients aged 6-70 years and 57 practically healthy control persons aged 12-70 years are described. In 14 patients the neoplasms were of a benign character, in 16 - borderline giant-cell bone tumor was diagnosed, and in 103 - malignant bone lesions including 39 osteosarcomas and 42 chondrosarcomas were revealed. The sPD-1 receptor concentrations in blood serum did not differ between control healthy persons and primary bone tumor patients, while serum sPD-L1 level in bone tumor patients was statistically significantly increased (p<0.0000001). By means of ROC curve construction a cut-off sPD-L1 level of 16.5 pg/ml was found that imposed 75,9% sensitivity and 75,4% specificity in relation to healthy control. However, the frequency of sPD-L1 levels exceeding 16.5 pg/ml was approximately similar in benign, borderline and malignant bone tumor patients. Analysis of the pattern of sPD-1 and sPD-L1 circulation in the peripheral blood of patients with the most prevalent malignant bone tumors - osteosarcoma and chondrosarcoma - demonstrated that in both sarcoma types sPD-L1 level was significantly higher than in control, but in patients with chondrogenic tumors the soluble ligand sPD-L1 dominates in the circulation, while in those with osteogenic tumors - sPD-1 receptor prevails. In particular, sPD-1 level is statistically significantly higher in patients with typical osteosarcoma than in those with typical chondrosarcoma (p=0.002437), and sPD-L1/sPD-1 concentration ratio in chondrosarcoma is highly significantly more than 2-fold higher than in osteosarcoma (0.81 and 0.35 respectively; p=0.000284). The sensitivity of sPD-L1 ≥16.5 pg/ml test in typical osteosarcoma patients' group comprised only 70.2%, and in those with typical chondrosarcoma - 84.6%. Serum sPD-1 and sPD-L1 concentrations in osteosarcoma and chondrosarcoma patients were not associated with the indices of tumor advancement, its histological grade, localization in the osseous system, and type of affected bone. Thus, it can be concluded that the ratio between circulating soluble forms of the receptor and the ligand of PD-1/PD-L signaling pathway differs between patients with chondrogenic and those with osteogenic tumors, sPD-L1 being diagnostically valuable mostly for chondrogenic bone neoplasms.

Key Immune Checkpoint PD-1/PD-L1 Signaling Pathway Components in the Blood Serum from Patients with Bone Tumors.

The levels of sPD-1 and sPD-L1 were analyzed in blood serum of 132 patients (age 14-70 years) with primary bone tumors: osteosarcoma (N=39), chondrosarcoma (N=42), Ewing sarcoma (N=9), chordoma (N=12), giant-cell bone tumor (GCBT) (N=16), benign neoplasms (N=14) and in and practically healthy subjects (age 19-58 years; N=27). sPD-L1 levels in all studied bone neoplasms were significantly higher than in the control. Serum sPD-1 level in GCBT patients was significantly higher than in the control, benign neoplasms, chondrosarcoma, and chordoma patients, but did not differ from osteosarcoma group. sPD-1 concentration in Ewing sarcoma was significantly higher than in chordoma and chondrosarcoma, but did not differ from the control. sPD-1 level in chondrosarcoma patients was also lower than in osteosarcoma, Ewing sarcoma, and in the control. Both sPD-1 and sPD-L1 concentrations were not significantly associated with the type of affected bone, process localization, disease stage, tumor histological grade, patients' age and sex. These results suggest the possibility of using these biological markers for preliminary assessment of the character of the process in the bone.

Glial Fibrillary Acidic Protein in the Diagnosis and Prognosis of Malignant Glial Tumors.

Serum levels of glial fibrillar acidic protein (GFAP) were analyzed in 317 patients with primary and metastatic tumors of the brain, 78 patients with neurological diseases, and 66 normal subjects. A significant increase in the basal level of GFAP was typical of patients with glioblastomas in comparison with other groups (patients with astrocytomas, cerebral metastases, benign tumors, non-tumor diseases, and healthy subjects). An association of GFAP levels with unfavorable prognosis of overall survival in patients with glioblastoma was revealed. The data attest to high specificity and sensitivity of GFAP as a biochemical marker of glioblastoma.

Immunochemical Diagnosis of Multiple Myeloma.

The diagnostic potentialities of complex immunochemical analysis of the serum and daily urine were evaluated in 118 patients with multiple myeloma. In 95 patients, we observed secretion of monoclonal intact immunoglobulins with heavy chains G (N=69), A (N=19), and M (N=4) and biclonal secretion of paraproteins G and A (N=3). Bence-Jones protein was detected in the sera and daily urine of 16 patients and Bence-Jones proteinuria alone was detected in 3 patients. The diagnostic sensitivity of serum immunoelectrophoresis in multiple myeloma is 94.1%. Analysis of paraproteinuria is particularly important in Bence-Jones myeloma, when paraprotein excretion may be not associated with paraproteinemia. Complex study by immunoelectrophoretic and immunoturbidimetric methods in multiple myeloma increases the diagnostic sensitivity to 99.2%.

Receptor Activator of Nuclear Transcription Factor NF-κB (RANK), Its Ligand RANKL, and Natural Inhibitor of RANKL Osteoprotegerin (OPG) in the Blood Serum of Patients with Primary Bone Tumors.

The content of components of the RANK/RANKL/OPG system, the key regulator of homeostasis in the bone tissue, in blood serum samples from 199 patients with primary bone neoplasms and 131 practically healthy volunteers was measured by ELISA. Borderline giantcell tumor of the bone with high osteoclastogenic and osteolytic activity is characterized by an increase in the level of all components of this system and highest ratio of sRANKL/OPG in the blood serum. Study indexes in patients with various benign neoplasms and tumor-like bone lesions were lower than in patients with giant-cell tumor. The patients with malignant bone tumors could be divided into 2 subgroups with opposite indexes of the RANK/RANKL/OPG system. The patients with osteosarcoma and Ewing sarcoma had a low level of sRANK, but a high level of sRANKL. The patients with chondrosarcoma and chordoma had a high level of sRANK, but a low level of sRANKL.

Components of the RANK/RANKL/OPG system, IL-6, IL-8, IL-16, MMP-2, and calcitonin in the sera of patients with bone tumors.

Serum levels of sRANKL, RANK, OPG, IL-8, IL-6, IL-16, MMP-2, and calcitonin were measured by ELISA in patients with malignant, borderline, and benign bone tumors and in healthy individuals (control). Serum levels of RANK, OPG, IL-8, IL-6, and the OPG/sRANKL ratio were significantly higher, while the level of MMP-2 was significantly lower in patients with bone tumors than in controls. Serum concentration of IL-16 in osteosarcoma patients was significantly lower than in chondrosarcoma patients. No significant differences between bone sarcomas of different differentiation were detected for any of the studied markers. Calcitonin level depended on the tumor location and type.

Software for evaluation of EPR-dosimetry performance.

Electron paramagnetic resonance (EPR) with tooth enamel is a method extensively used for retrospective external dosimetry. Different research groups apply different equipment, sample preparation procedures and spectrum processing algorithms for EPR dosimetry. A uniform algorithm for description and comparison of performances was designed and implemented in a new computer code. The aim of the paper is to introduce the new software 'EPR-dosimetry performance'. The computer code is a user-friendly tool for providing a full description of method-specific capabilities of EPR tooth dosimetry, from metrological characteristics to practical limitations in applications. The software designed for scientists and engineers has several applications, including support of method calibration by evaluation of calibration parameters, evaluation of critical value and detection limit for registration of radiation-induced signal amplitude, estimation of critical value and detection limit for dose evaluation, estimation of minimal detectable value for anthropogenic dose assessment and description of method uncertainty.