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Background: One of the obstacles to autologous chondrocyte implantation (ACI) is obtaining a large quantity of chondrocytes without depletion of their properties. The conditioned medium (CM) from different subpopulations of stem cells (mesenchymal stromal cells (MSC) or induced pluripotent stem cells (iPSC)) could be a gamechanger. MSCs' potential is related to the donor's health and age, which could be omitted when, as a source, iPSCs are used. There is a lack of data regarding their use in the chondrocyte culture expansion. Thus, we wanted to verify whether iPSC-CM could be beneficial for the cell culture of primary chondrocyte cells., Methods: We added the iPSC-CMs from GPCCi001-A and ND 41658*H cells to the culture of primary chondrocyte cell lines isolated from OA patients (n = 6) for other two passages. The composition of the CM was evaluated using Luminex technology. Then, we analysed the senescence, proliferation rate and using flow cytometry: viability, distribution of cell cycle phases, production of reactive oxygen species (ROS) and double-strand breaks. The cartilage-related markers were evaluated using Western blot and immunofluorescence. Additionally, a three-dimensional cell culture was used to determine the potential to form cartilage particles., Results: iPSC-CM increased proliferation and diminished cell ROS production and senescence. CM influenced the cartilage-related protein expression and promoted the growth of cartilage particles. The cell exposed to CM did not lose the ECM proteins, suggesting the chondroprotective effect for prolonged culture time., Conclusion: Our preliminary results suggest a beneficial effect on maintaining chondrocyte biology during in vitro expansion., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Gastric cancer (GC) is one of the most frequently diagnosed cancers in the world. Although the incidence is decreasing in developed countries, the treatment results are still unsatisfactory. The standard treatment for locally advanced gastric cancer (LAGC) is gastrectomy with perioperative chemotherapy. The association of selected microRNAs (miRNAs) with chemoresistance was assessed using archival material of patients with LAGC. Histological material was obtained from each patient via a biopsy performed during gastroscopy and then after surgery, which was preceded by four cycles of neoadjuvant chemotherapy (NAC) according to the FLOT or FLO regimen. The expression of selected miRNAs in the tissue material was assessed, including miRNA-21-3p , miRNA-21-5p , miRNA-106a-5p , miRNA-122-3p , miRNA-122-5p , miRNA-143-3p , miRNA-143-5p , miRNA-203a-3p , miRNA-203-5p , miRNA-551b-3p , miRNA-551b-5p , and miRNA-574-3p . miRNA expression was assessed using quantitative reverse transcription polymerase chain reaction (qRT-PCR). The response to NAC was assessed using computed tomography of the abdomen and chest and histopathology after gastrectomy. The statistical analyses were performed using GraphPad Prism 9. The significance limit was set at p < 0.05. We showed that the expression of miR-143-3p , miR-143-5p , and miR-574-3p before surgery, and miR-143-5p and miR-574-3p after surgery, decreased in patients with GC. The expression of miR-143-3p , miR-143-5p , miR-203a-3p , and miR-551b-5p decreased in several patients who responded to NAC. The miRNA most commonly expressed in these cases was miRNA-551b-5p . Moreover, it showed expression in a patient whose response to chemotherapy was inconsistent between the histopathological results and computed tomography. The expression of miR-143-3p , miR-143-5p , miR-203a-3p , and miR-551b-5p in formalin-fixed paraffin-embedded tissue (FFPET) samples can help differentiate between the responders and non-responders to NAC in LAGC. miR-143-3p , miR-143-5p , and miR-574-3p expression may be used as a potential diagnostic tool in GC patients. The presence of miR-551b-5p may support the correct assessment of a response to NAC in GC via CT.

The HER2 gene is a biomarker for breast cancer prognosis and treatment. Overexpression of HER2 protein determined by immunohistochemistry (IHC) or amplification of the HER2 gene determined by fluorescence in situ hybridization (FISH) is a condition for qualifying patients for anti-HER2 therapy. Due to the high toxicity of anti-HER2 treatment, proper patient selection is essential. In our study we compared 40 cases with IHC staining of HER2 antibody determined by Ventana PATHWAY anti-HER2/neu antibody (4B5) as HER2 2+ with the new antibody (HercepTest™ mAb PharmDx [Dako Omnis] [GE001]). Then using a double-blind study we compared the (IHC) evaluation with FISH results. In 65% of cases (26/40) the IHC 2+ score remained unchanged, in 32.5% of cases (13/40) expression of HER2 protein after IHC with new antibody was indicated as 3+ score, and in one case we observed a decrease of HER2 protein expression to 1+. In all cases but one, in which we found IHC HER 3+ with new antibody, there was FISH amplification. We have reason to believe that the new antibody will reduce the diagnostic time and avoid unnecessary costs. Due to the small study group, further investigation is needed.

The development of induced pluripotent stem cells has brought unlimited possibilities to the field of regenerative medicine. This could be ideal for treating osteoarthritis and other skeletal diseases, because the current procedures tend to be short-term solutions. The usage of induced pluripotent stem cells in the cell-based regeneration of cartilage damages could replace or improve on the current techniques. The patient's specific non-invasive collection of tissue for reprogramming purposes could also create a platform for drug screening and disease modelling for an overview of distinct skeletal abnormalities. In this review, we seek to summarise the latest achievements in the chondrogenic differentiation of pluripotent stem cells for regenerative purposes and disease modelling.

Uveal melanoma (UM) is the most common primary tumor of the eye diagnosed in adults, associated with a high risk of metastasis and thereby, poor prognosis. Among known risk factors for the development of metastatic disease is the loss of BAP1 expression and chromosome 3 monosomy in the primary tumor. However, the expression levels of specific micro RNAs (miRNA) in tumor tissue may also serve as a valuable marker for determining the risk of metastatic disease in patients with primary uveal melanoma. In our study, we analyzed the miRNA expression data of cases selected from The Cancer Genome Atlas study on uveal melanoma, and determined a panel of 15 miRNAs differentially expressed between patients with primary and metastatic disease. Next, 6 miRNAs were validated on a group of 46 tumor samples from primary and metastatic patients. We have shown, that expression of hsa-miR-592, hsa-miR-346, and hsa-miR-1247 was significantly increased, while hsa-miR-506 and hsa-miR-513c were decreased in the tumors of patients with metastatic disease. Hsa-miR-196b expression did not differ between the two subgroups, however, we showed significant correlation with BAP1 expression. Moreover, hsa-miR-592 also showed correlation with monosomy 3 tumors. Gene ontology analysis revealed involvement of those miRNAs with cellular processes mediating the metastatic process. Our results showed that miRNAs play an important role in the deregulation of several oncogenic pathways in UM and can, thereby, promote metastatic spread to distant organs. Moreover, differentially expressed miRNAs may be used as an interesting biomarker for the assessment of metastatic risk in uveal melanoma patients.

The yeast Saccharomyces cerevisiae was used as a model eukaryotic organism to study the uptake of diamino acid derivatives of porphyrins and their phototoxicity with particular emphasis on possible mutagenic effects. The water-soluble hematoporphyrin derivatives diarginate (HpD[Arg]2) and 1-arginin di(N-amino acid)-protoporphyrinate used in this study are effective photosensitizers in tumor photodynamic therapy. Depending on the amino acid substituent, the porphyrin derivatives differ in their affinity for yeast cells. It is shown that HpD(Arg)2 and PP(Met)2 (Arg)2 penetrate into the yeast cell and are metabolized. Both compounds sensitize yeast cells to photodamage but have no mutagenic effect on nuclear or mitochondrial genomes.

Three phosphatases active on phosphocasein (PhosphoCasein Phosphatases) termed PCP-I, PCP-II and PCP-III were isolated from maize seedlings by DEAE-cellulose chromatography and were shown to display a different specificity toward a variety of phosphorylated substrates including pNPP, phosphohistones, phosphorylase a and several phosphopeptides containing either phosphoserine or phosphothreonine. PCP-I and PCP-II bind to heparin-Sepharose, retain a remarkable pNPP activity, are uncapable to dephosphorylate phosphorylase a, and display striking activity toward the acidic phosphopeptide AS[32P]EEEEE. They also by far prefer phosphoseryl peptide RRAS[32P]VA over its phosphothreonyl derivative and are unsensitive to okadaic acid up to 1 microM. These properties are not consistent with the belonging of PCP-I and -II to any of the known classes of protein phosphatases and suggest that they are acidic phosphatases. Conversely, PCP-III is essentially free of pNPP activity; it readily dephosphorylates phosphohistone H1 and phosphorylase a and it displays a striking preference toward the phosphothreonyl peptides (RRAT[32P]VA and RRREEET[32P]EEEAA), while the phosphoseryl peptides (RRAS[32P]VA and AS[32P]EEEEE) are very poor substrates of the enzyme. These properties together with the findings that PCP-III does not bind to heparin-Sepharose and is highly sensitive to okadaic acid (IC50 = 0.2 nM) allow to identify PCP-III with a protein phosphatase of the PP-2A class.