Human cells with osteogenic potential in bone tissue research.

Bone regeneration after injury or after surgical bone removal due to disease is a serious medical challenge. A variety of materials are being tested to replace a missing bone or tooth. Regeneration requires cells capable of proliferation and differentiation in bone tissue. Although there are many possible human cell types available for use as a model for each phase of this process, no cell type is ideal for each phase. Osteosarcoma cells are preferred for initial adhesion assays due to their easy cultivation and fast proliferation, but they are not suitable for subsequent differentiation testing due to their cancer origin and genetic differences from normal bone tissue. Mesenchymal stem cells are more suitable for biocompatibility testing, because they mimic natural conditions in healthy bone, but they proliferate more slowly, soon undergo senescence, and some subpopulations may exhibit weak osteodifferentiation. Primary human osteoblasts provide relevant results in evaluating the effect of biomaterials on cellular activity; however, their resources are limited for the same reasons, like for mesenchymal stem cells. This review article provides an overview of cell models for biocompatibility testing of materials used in bone tissue research.

In Situ Hydroxyapatite Synthesis Enhances Biocompatibility of PVA/HA Hydrogels.

Bone tissue engineering tries to simulate natural behavior of hard tissues. This study aimed to produce scaffolds based on polyvinyl alcohol (PVA) and hyaluronic acid (HA) with hydroxyapatite (HAp) incorporated in two different ways, by in situ synthesis and physical mixing of pre-prepared HAp. In situ synthesis resulted in calcium deficient form of HAp with lower crystallinity. The proliferation of human osteoblast-like cells MG-63 proved to be better in the scaffolds with in situ synthesized HAp compared to those with physically mixed pre-prepared HAp. For scaffolds with PVA/HA/HAp ratio 3:1:2, there was significantly higher initial adhesion (p = 0.0440), as well as the proliferation in the following days (p < 0.001). It seemed to be advantageous improve the properties of the scaffold by in situ synthesizing of HAp directly in the organic matrix.

Biological Evaluation of Polyvinyl Alcohol Hydrogels Enriched by Hyaluronic Acid and Hydroxyapatite.

This study aimed to develop polyvinyl alcohol (PVA) -based scaffold enriched with hyaluronic acid (HA) and hydroxyapatite (HAp) using physical crosslinking by freezing-thawing method. We accomplished biological evaluation of scaffolds, swelling degree, bioactivity assessment, and hemolytic test. The results showed that all types of scaffolds should be safe for use in the human body. The culturing of human osteoblast-like cells MG-63 and their proliferation showed better adhesion of cells due to the presence of HA and confirmed better proliferation depending on the amount of HAp. This paper gives the optimal composition of the scaffold and the optimal amount of the particular components of the scaffold. Based on our results we concluded that the best PVA/HA/HAp combination is in the ratio 3:1:2.

One-step nucleic acid amplification vs ultrastaging in the detection of sentinel lymph node metastasis in endometrial cancer patients.

BACKGROUND AND OBJECTIVES: Utilisation of the one-step nucleic acid amplification (OSNA) molecular biology method for the detection of the metastatic involvement of sentinel lymph nodes (SLNs) in endometrial cancer (EC) patients. A comparison with histopathological ultrastaging and a description of the clinical consequences. METHODS: Surgically treated EC patients underwent detection of SLNs. Nodes greater than 5 mm were cut into sections 2-mm thick parallel to the short axis of the node. Odd sections were examined according to the OSNA method, while even ones according to an appropriate ultrastaging protocol. Nodes less than or equal to 5 mm were cut into halves along the longitudinal axis with one half examined according to the OSNA method and the other half by ultrastaging. RESULTS: Fifty-eight patients were included and 135 SLNs were acquired. Both ultrastaging and OSNA agreed on 116 results. According to the OSNA method, 20.69% more patients were classified into International Federation of Gynecology and Obstetrics (FIGO) stage III. When comparing the results of the OSNA method to the conclusions of ultrastaging as a reference method, sensitivity of 90.9%, specificity of 85.5% and concordance of 85.9% were attained. CONCLUSIONS: The results of the OSNA method showed a higher frequency of detection of micrometastases and included 20.69% more patients into FIGO stage III.

A more sensitive detection of micrometastases of NSCLC in lymph nodes using the one-step nucleic acid amplification (OSNA) method.

BACKGROUND: Detection of tumor cells in lymph nodes (LNs) removed during the treatment of pulmonary tumor by radical surgery is limited by the possibilities of standard histopathological methods. The goal of this study was to obtain more accurate pTNM status by a more sensitive detection of micrometastases in LNs. METHODS: A total of 885 LNs, an average of 13.8 LNs per patient, were removed during 64 surgeries. LNs from the same zone were pooled together as a group, five groups of LNs were examined in each patient. A total of 320 groups of LNs were examined. One-step nucleic acid amplification (OSNA) method was compared to standard histopathological examination with haematoxylin-eosin (H&E) staining and CK19 immunohistochemistry, specifically by an ultimate analysis of all intraoperatively removed LNs. RESULTS: Identical results for H&E and OSNA examinations were recorded in 286 groups of LNs (89.4%). In total, positive examinations were recorded in 27 groups of LNs (8.4%) using the OSNA method, which were H&E negative. In seven groups of LNs (2.2%), the H&E examination was positive, while OSNA method produced negative results. CONCLUSIONS: The OSNA examination led to a higher pTNM stage classification in 14 (21.9%) patients. The clinical significance remains the subject of follow-up research.

The origin and development of fat droplet and its role in health and illness.

Lipid droplets are found in most cells, where they are needed for lipid metabolism and energy homeostasis. Their biogenesis is still not entirely described process, in which an organelle with monomolecular layer on the surface originates from two-layer membrane of the smooth endoplasmic reticulum. Large lipid droplets can be formed either by growth or by fusion of smaller lipid droplets. Their basic functions are controlled lipid deposition and lipid metabolism and the protection of the intracellular environment from lipotoxicity. Currently, dysfunction of lipid droplet is associated with a number of diseases such as obesity, cardiometabolic syndrome, tumor and neurodegenerative diseases, lipodystrophy and cachexia. Keywords: lipid droplet, adipocyte, endoplasmic reticulum, perilipin, obesity, type 2 diabetes mellitus, lipodystroph.

Prognostic Value of Tumor Tissue Up-regulated microRNAs in Clear Cell Renal Cell Carcinoma (ccRCC).

BACKGROUND/AIM: The management of patients with clear cell renal cell carcinoma (ccRCC) includes prognosis assessment based on TNM classification and biochemical markers. This approach stratifies patients with advanced ccRCC into groups of favorable, intermediate, and poor prognosis. The aim of the study was to improve prognosis estimation using microRNAs involved in the pathogenesis of ccRCC. PATIENTS AND METHODS: The study was based on a histologically-verified set of matched ccRCC FFPE tissue samples (normal renal tissue, primary tumor, metastasis, n=20+20+20). The expression of 2,549 microRNAs was analyzed using the SurePrint G3 Human miRNA microarray kit (Agilent Technologies). Prognostic value of significantly deregulated microRNAs was further evaluated on microRNA expression and clinical data of 475 patients obtained from TCGA Kidney Clear Cell Carcinoma (KIRC) database. RESULTS: There were 13 up-regulated and 6 down-regulated microRNAs in tumor tissues compared to control tissues. Among them, survival analysis revealed those with prognostic significance. Patients with high expression of miR-21, miR-27a, miR-34a, miR-106b, miR-210, and miR-342 showed significantly unfavorable outcome. The opposite was observed for miR-30e, patients with low expression had significantly shorter survival. CONCLUSION: The inclusion of these microRNAs in a prognostic panel holds the potential to enhance stratification scoring systems, on which the treatment of ccRCC patients is based.

Next Generation Sequencing Analysis and its Benefit for Targeted Therapy of Lung Adenocarcinoma.

BACKGROUND/AIM: Targeted therapy has become increasingly important in treating lung adenocarcinoma, the most common subtype of lung cancer. Next-generation sequencing (NGS) enables precise identification of specific genetic alterations in individual tumor tissues, thereby guiding targeted therapy selection. This study aimed to analyze mutations present in adenocarcinoma tissues using NGS, assess the benefit of targeted therapy and evaluate the progress in availability of targeted therapies over last five years. PATIENTS AND METHODS: The study included 237 lung adenocarcinoma patients treated between 2018-2020. The Archer FusionPlex CTL panel was used for NGS analysis. RESULTS: Gene variants covered by the panel were detected in 57% patients and fusion genes in 5.9% patients. At the time of the study, 34 patients (14.3% of patients) were identified with a targetable variant. Twenty-five patients with EGFR variants, 8 patients with EML4-ALK fusion and one patient with CD74-ROS1 fusion received targeted therapy. Prognosis of patients at advanced stages with EGFR variants treated by tyrosine kinase inhibitors and patients with EML4-ALK fusion treated by alectinib was significantly favorable compared to patients without any targetable variant treated by chemotherapy (p=0.0172, p=0.0096, respectively). Based on treatment guidelines applicable in May 2023, the number of patients who could profit from targeted therapy would be 64 (27.0% of patients), this is an increase by 88% in comparison to recommendations valid in 2018-2020. CONCLUSION: As lung adenocarcinoma patients significantly benefit from targeted therapy, the assessment of mutational profiles using NGS could become a crucial approach in the routine management of oncological patients.

Intracerebellar application of P19-derived neuroprogenitor and naive stem cells to Lurcher mutant and wild type B6CBA mice.

BACKGROUND: Neurotransplantation has great potential for future treatments of various neurodegenerative disorders. Preclinically, the Lurcher mutant mouse represents an appropriate model of genetically-determined olivocerebellar degeneration. The aim of the present study was to assess survival of naïve and neurally differentiated P19 carcinoma stem cells following transplantation into the cerebellum of Lurcher mice and wild type littermates. MATERIAL/METHODS: Adult normal wild type (n=51) and Lurcher mutant mice (n=87) of the B6CBA strain were used. The mean age of the animals at the time of transplantation was 261.5 days. Suspension of naive and neurally differentiated P19 carcinoma stem cells was injected into the cerebellum of the mice. In the Lurcher mutants, 2 depths of graft injection were used. Three weeks after implantation the brains of experimental animals were examined histologically. RESULTS: Survival of neuroprogenitor grafts at a depth of 1.6 mm was significantly higher in wild type vs. Lurcher mutant mice. In wild type mice, the typical graft localization was in the middle of the cerebellum, whereas in Lurcher mice the graft was never found inside the degenerated cerebellum and was primarily localized in the mesencephalon. CONCLUSIONS: We conclude that the appearance and low survival rate of cerebellar P19 carcinoma stem cell grafts in the Lurcher mutant mice weigh against the therapeutic value of this cell line in preclinical studies of neurodegeneration.

[Morphology and etiopathogenesis of the abdominal aortic aneurysm]. / Morfologie a etiopatogeneze aneuryzmatu brisní aorty.

The paper summarizes the latest research on the abdominal aorta aneurysm etiopathogenesis and compares normal aorta morphology with changes in the aortic aneurysm wall. The role of risk factors, especially hemodynamic and genetic, is discussed in detail. Special attention is paid to inflammatory processes including cytokines and matrix degrading proteases that contribute to the development of aneurysm. The role of thrombus and the current results of research into biomarkers indicating the risks and progression of the disease are analysed. Finally, a review of pharmacomodulation of the aortic aneurysm using statins, antibiotics, antihypertensive and nonsteroidal antiinflammatory drugs is presented.

[Vitamin D metabolism]. / Metabolizmus vitaminu D.

Vitamin D is the collective name for cholecalciferol (vitamin D3) and ergocalciferol (vitamin D2), which are precursors of hormones with an important role in regulation of the metabolism of calcium and phosphates. This review article describes the production of vitamin D3 in the skin by ultraviolet radiation from sunlight, transport of vitamin D and its metabolites in blood, formation of the active hormonal form - calcitriol (1,25-dihydroxyvitamin D) by hydroxylation in the liver and kidney, and termination of the action by catabolism to inactive metabolites.

Applications of Liquid Biopsies in Non-Small-Cell Lung Cancer.

The concept of liquid biopsy as an analysis tool for non-solid tissue carried out for the purpose of providing information about solid tumors was introduced approximately 20 years ago. Additional to the detection of circulating tumor cells (CTCs), the liquid biopsy approach quickly included the analysis of circulating tumor DNA (ctDNA) and other tumor-derived markers such as circulating cell-free RNA or extracellular vesicles. Liquid biopsy is a non-invasive technique for detecting multiple cancer-associated biomarkers that is easy to obtain and can reflect the characteristics of the entire tumor mass. Currently, ctDNA is the key component of the liquid biopsy approach from the point of view of the prognosis assessment, prediction, and monitoring of the treatment of non-small-cell lung cancer (NSCLC) patients. ctDNA in NSCLC patients carries variants or rearrangements that drive carcinogenesis, such as those in EGFR, KRAS, ALK, or ROS1. Due to advances in pharmacology, these variants are the subject of targeted therapy. Therefore, the detection of these variants has gained attention in clinical medicine. Recently, methods based on qPCR (ddPCR, BEAMing) and next-generation sequencing (NGS) are the most effective approaches for ctDNA analysis. This review addresses various aspects of the use of liquid biopsy with an emphasis on ctDNA as a biomarker in NSCLC patients.

BAI1 as a Prognostic Marker of Clear Cell Renal Cell Carcinoma (ccRCC).

BACKGROUND/AIM: The treatment of advanced clear cell renal cell carcinoma (ccRCC) is based on stratification of patients according to prognosis (favorable, intermediate, and poor). The aim of the study was to improve prognostication by biomarkers involved in angiogenesis. PATIENTS AND METHODS: The study group consisted of 20 patients who underwent surgery for ccRCC. Gene expression analysis was peformed on a set of matched (primary tumor, metastasis, n=20+20) FFPE tissue samples. An additional analysis was done on expression data of 606 patients obtained from the TCGA Kidney Clear Cell Carcinoma (KIRC) database. Quantitative estimation of mRNA of selected genes (TaqMan human Angiogenesis Array, 97 genes) was performed by a real-time RT-PCR method with TaqMan® arrays. RESULTS: Using the Cox regression model, 4 genes (PDGFB, FGF4, EPHB2 and BAI1) were identified whose expression was related to progression-free interval (PFI). Further analysis using the Kaplan Meier method conclusively revealed the relationship of BAI1 expression to prognosis (both datasets). Patients with higher BAI1 expression had significantly shorter PFI and overall survival. CONCLUSION: We showed that tumor tissue BAI1 expression level is a prognostic marker in ccRCC. Therefore, this gene might be involved in a prognostic panel to improve scoring systems on which the management of metastatic ccRCC patients is based.

Diagnostic and prognostic significance of inflammatory markers in lung cancer-associated pleural effusions.

Besides massive expression in inflammatory pleural effusions, inflammatory markers are also present in cancerinduced pleural effusions. Recent advances in cancer biology point to a role of inflammatory signaling in cancer and encourage reconsidering the diagnostic and prognostic value of inflammatory markers. Here an attempt was made to relate protein levels of inflammatory markers to underlying malignant processes in the pleural space. Pleural effusions from lung cancer patients (n=116) were subjected to a multifactorial analysis covering 13 inflammatory markers. The composition of tumor-associated effusions was compared with that of parainflammatory pleural effusions (n=30), transudates (n=18), and serum values, and evaluated in relation to cancer origin, histology, cytology, pleural involvement, treatment history, and survival time. Inflammatory markers were significantly expressed in pleural effusions of paraneoplastic origin when compared to transudates and most serum levels. Values in pleura-invading and metastatic tumor-associated effusions were typically higher than those of other tumors. Many markers correlated negatively with survival, most prominently IL-8 (r=-0.36, p=0.001) and VEGF (r=-0.35, p=0.001). It appears that most inflammatory markers are highly expressed in tumor-associated pleural effusions, reflecting to some extent tumor origin and localization. Despite the lower efficacy of inflammatory markers in the differentiation between exudative pleural effusions, some inflammatory markers may represent potential prognostic markers of malignant processes in the pleural space.

Prognostic Significance of Lymph Node Examination by the OSNA Method in Lung Cancer Patients-Comparison with the Standard Histopathological Procedure.

The aim of the study was to compare the prognostic significance of lymph node status of patients with lung cancer analyzed by three different methods: hematoxylin and eosin (H&E), immunohistochemistry of cytokeratin 19 (IHC CK19), and One-Step Nucleic Acid Amplification (OSNA). The clinical relevance of the results was evaluated based on relation to prognosis; the disease-free interval (DFI) and overall survival (OS) were analyzed. During radical surgical treatment, a total of 1426 lymph nodes were obtained from 100 patients, creating 472 groups of nodes (4-5 groups per patient) and examined by H&E, IHC CK19 and OSNA. The median follow-up was 44 months. Concordant results on the lymph node status of the H&E, IHC CK19 and OSNA examinations were reported in 78% of patients. We recorded shorter OS in patients with positive results provided by both OSNA and H&E. The study demonstrated a higher percentage of detected micrometastases in lymph nodes by the OSNA method. However, the higher sensitivity of the OSNA, with the cut-off value 250 copies of mRNA of CK19/µL, resulted in a lower association of OSNA positivity with progress of the disease compared to H&E. Increasing the cut-off to 615 copies resulted in an increase in concordance between the OSNA and H&E, which means that the higher cut-off is more relevant in the case of lung tumors.

Repeated Exposure of Nanostructured Titanium to Osteoblasts with Respect to Peri-Implantitis.

Titanium offers excellent biocompatibility and extraordinary mechanical properties. As a result, it is used as a material for dental implants. Implants infected by peri-implantitis can be cleaned for successful re-osseointegration. Optimal surface properties, such as roughness and wettability, have a significant impact on cell adhesion. The aim of this study was to evaluate the adhesion and proliferation of osteoblasts on the surface of repeatedly cleaned nanostructured titanium samples. Human osteoblast-like cells MG-63 were seeded on nanostructured titanium specimens manufactured from rods produced by the equal channel angular pressing. For surface characterization, roughness and wettability were measured. Cell adhesion after 2 h as well as cell proliferation after 48 h from plating was assessed. We have found that this repeated cleaning of titanium surface reduced cell adhesion as well as proliferation. These events depend on interplay of surface properties, such as wettability, roughness and topography. It is difficult to distinguish which factors are responsible for these events and further investigations will be required. However, even after the several rounds of repeated cleaning, there was a certain rate of adhesion and proliferation recorded. Therefore the attempts to save failing implants by using in situ cleaning are promising.

Fabrication of Scaffolds for Bone-Tissue Regeneration.

The present article describes the state of the art in the rapidly developing field of bone tissue engineering, where many disciplines, such as material science, mechanical engineering, clinical medicine and genetics, are interconnected. The main objective is to restore and improve the function of bone tissue by scaffolds, providing a suitable environment for tissue regeneration and repair. Strategies and materials used in oral regenerative therapies correspond to techniques generally used in bone tissue engineering. Researchers are focusing on developing and improving new materials to imitate the native biological neighborhood as authentically as possible. The most promising is a combination of cells and matrices (scaffolds) that can be fabricated from different kinds of materials. This review summarizes currently available materials and manufacturing technologies of scaffolds for bone-tissue regeneration.

Plasma microRNA Levels Combined with CEA and CA19-9 in the Follow-Up of Colorectal Cancer Patients.

Colorectal cancer (CRC) ranks among the most common cancers worldwide. Surgical removal remains the best strategy for treatment of resectable tumors. An important part of caring for patients after surgery is monitoring for early detection of a possible relapse of the disease. Efforts are being made to improve the sensitivity and specificity of routinely used carcinoembryonic antigen (CEA) with the use of additional biomarkers such as microRNAs. The aim of our study was to evaluate the prognostic potential of microRNAs and their use as markers of disease recurrence. The quantitative estimation of CEA, CA19-9, and 22 selected microRNAs (TaqMan Advanced miRNA Assays) was performed in 85 paired (preoperative and postoperative) blood plasma samples of CRC patients and in samples taken during the follow-up period. We have revealed a statistically significant decrease in plasma levels for miR-20a, miR-23a, miR-210, and miR-223a (p = 0.0093, p = 0.0013, p = 0.0392, and p = 0.0214, respectively) after surgical removal of the tumor tissue. A statistically significant relation to prognosis (overall survival; OS) was recorded for preoperative plasma levels of miR-20a, miR-21, and miR-23a (p = 0.0236, p = 0.0316, and p =0.0271, respectively) in a subgroup of patients who underwent palliative surgery. The best discrimination between patients with favorable and unfavorable outcomes was achieved by a combination of CEA, CA19-9 with miR-21, miR-20a, and miR-23a (p < 0.0001). The use of these microRNAs for early disease recurrence detection was affected by a low specificity in comparison with CEA and CA19-9. CEA and CA19-9 had high specificity but low sensitivity. Our results show the benefit of combining currently used standard biomarkers and microRNAs for precise prognosis estimation.

Follicular fluid levels of anti-Müllerian hormone, insulin-like growth factor 1 and leptin in women with fertility disorders.

Anti-Müllerian hormone (AMH), insulin-like growth factor 1 (IGF1) and leptin are produced in the granulosa cells of follicles and play an important role in the growth and maturation of follicles. The aim of our study was to monitor AMH, IGF1 and leptin levels in a group of healthy women and compare them to a group of women with fertility disorders. The second aim was the evaluation of biomarker levels in relation to the identified cause of infertility. Totally, 146 females were enrolled into our study. Seventy-two healthy controls and seventy-four females with fertility disorders were divided into four subgroups: anovulation, endometriosis, fallopian tube damage, unknown reason. IGF1 was the only biomarker with significantly lower levels throughout the entire group with fertility disorders. We did not identify any statistically significant differences for AMH and leptin. Regarding subgroups, significant differences were only observed in the group of anovulatory women. AMH and leptin showed higher levels while IGF1 showed lower levels. In conclusion, levels of AMH, IGF1 and leptin found in follicular fluid are sensitive markers for anovulatory fertility disorders. AMH, IGF1 and leptin levels in follicular fluid have no relation to the fertility disorders caused by endometriosis, fallopian tube damage or disorders with unknown etiology. ABBREVIATIONS: AMH: anti-Müllerian hormone; IGF1: insulin-like growth factor 1; PCOS: polycystic ovary syndrome.

Proliferation of Osteoblasts on Laser-Modified Nanostructured Titanium Surfaces.

Nanostructured titanium has become a useful material for biomedical applications such as dental implants. Certain surface properties (grain size, roughness, wettability) are highly expected to promote cell adhesion and osseointegration. The aim of this study was to compare the biocompatibilities of several titanium materials using human osteoblast cell line hFOB 1.19. Eight different types of specimens were examined: machined commercially pure grade 2 (cpTi2) and 4 (cpTi4) titanium, nanostructured titanium of the same grades (nTi2, nTi4), and corresponding specimens with laser-treated surfaces (cpTi2L, cpTi4L, nTi2L, nTi4L). Their surface topography was evaluated by means of scanning electron microscopy. Surface roughness was measured using a mechanical contact profilometer. Specimens with laser-treated surfaces had significantly higher surface roughness. Wettability was measured by the drop contact angle method. Nanostructured samples had significantly higher wettability. Cell proliferation after 48 hours from plating was assessed by viability and proliferation assay. The highest proliferation of osteoblasts was found in nTi4 specimens. The analysis of cell proliferation revealed a difference between machined and laser-treated specimens. The mean proliferation was lower on the laser-treated titanium materials. Although plain laser treatment increases surface roughness and wettability, it does not seem to lead to improved biocompatibility.