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Abstract: Malignant gliomas are rapidly growing tumours that extensively invade the brain and have bad prognosis. Our study was performed to assess the metabolic effects of bevacizumab on the glioma cells carrying the IDH1 mutation, a mutation, associated with better prognosis and treatment outcome. Bevacizumab is known to inhibit tumour growth by neutralizing the biological activity of vascular endothelial growth factor (VEGF). However, the direct effects of bevacizumab on tumour cells metabolism remain poorly known. Materials and methods The immunoassay and MTT assay were used to assess the concentration of secreted VEGF and cell viability after bevacizumab exposure. Metabolomic studies on cells were performed using high resolution magic angle spinning spectroscopy (HRMAS). Results mIDH1-U87 cells secreted VEGF (13 ng/mL). Regardless, bevacizumab had no cytotoxic effect, even after a 72h exposure and with doses as high as 1 mg/mL. Yet, HRMAS analysis showed a significant effect of bevacizumab (0.1 mg/mL) on the metabolic phenotype of mIDH1-U87 cells with elevation of 2-hydroxyglutarate and changes in glutamine group metabolites (alanine, glutamate, glycine) and lipids (polyunsaturated fatty acids [PUFA], glycerophosphocholine, and phosphocholine). Conclusions In mIDH1-U87 cells, changes in glutamine group metabolites and lipids were identified as metabolic markers of bevacizumab treatment. These data support the possibility of a functional tricarboxylic acid cycle that runs in reductive manner, as a probable mechanism of action of bevacizumab in IDH1 mutated gliomas and propose a new target pathway for effective treatment of malignant gliomas.
Keywords: symptomatic pseudoprogression, atypical response, immunotherapy, lung cancer, idh1 mutation, malignant glioma, bevacizumab, metabolic fingerprint
Published in DiRROS: 11.06.2024; Views: 30; Downloads: 7
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Keywords: radiotherapy, adjuvant radiotherapy, cardiotoxicity, breast cancer
Published in DiRROS: 10.06.2024; Views: 29; Downloads: 9
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Abstract: With introduction of immunotherapy (IT) into the treatment of advanced non-small-cell lung cancer (NSCLC), a need for predictive biomarker became apparent. Programmed death ligand 1 (PD-L1) protein expression is most widely explored predictive marker for response to IT. We assessed PD-L1 expression in tumor cells (TC) and immune cells (IC) of squamous-cell carcinoma (SCC) and adenocarcinoma (AC) patients. We obtained 54 surgically resected tumor specimens and assessed PD-L1 expression by immunohistochemistry after staining them with antibody SP142 (Ventana, USA). Clinicopathological characteristics were acquired from the hospital registry database. Results were analyzed according to cut-off values of % 5% and % 10% of PD-L1 expression on either TC or IC. 29 (54%) samples were AC and 25 (46%) were SCC. PD-L1 expression was significantly higher in TC of SCC compared to AC at both cut-off values (52% vs. 17%, p = 0.016 and 52% vs. 14%, p = 0.007, respectively) no difference in PD-L1 expression in IC of SCC and AC was found. In AC alone, PD-L1 expression was significantly higher in IC compared to TC at both cut-off values (72% vs. 17%, p < 0.001 and 41% vs. 14%, p = 0.008, respectively), while no significant difference between IC and TC PD-L1 expression was revealed in SCC. Our results suggest a significantly higher PD-L1 expression in TC of SCC compared to AC, regardless of the cut-off value. PD-L1 expression in IC is high in both histological subtypes of NSCLC, and adds significantly to the overall positivity of AC but not SCC.
Keywords: lung cancer, squamous-cell lung cancer, adenocarcinoma, tumor cells, immune cells, PD-L1 expression
Published in DiRROS: 31.05.2024; Views: 87; Downloads: 86
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Abstract: The study was aimed to characterize tumor response after combined treatment employing electrochemotherapy with IL-12 gene electrotransfer in dogs with spontaneous mast cell tumors (MCT). Materials and methods. Eleven dogs with eleven MCTs were included in the study. Histological changes were investigated in biopsy specimens collected before the treatment (T0), and 4 (T1) and 8 weeks (T2) later. Cellular infiltrates were characterized immunohistochemically by using anti CD3, CD20, Foxp3 (Treg), CD68 and anti MHC-class II antibodies. Proliferation and anti-apoptotic activity of neoplastic cells were assessed using anti Ki-67 and Bcl-2 antibodies. Angiogenetic processes were investigated immunohistochemically by using anti Factor VIII and anti CD31 antibodies and micro vessel density quantification. Results. Histopathological examination of samples at T0 confirmed the diagnosis and the presence of scanty infiltrates consisted mainly of T-lymphocytes and macrophages. At T1 and T2 neoplastic cells were drastically reduced in 7/11 cases, small clusters of neoplastic cells were detected in 3/11 cases and 1/11 cases neoplastic cells were still evident. Proliferation activity of neoplastic cells was significantly reduced at T1 and T2 and expression of anti-apoptotic protein at T1. Microvessel density was drastically reduced in all samples after treatment. The number of T-lymphocytes increased at T1, although not significant, while Treg were significant higher at T1 and macrophages at T2. Conclusions. The combined electrochemotherapy and IL-12 gene electrotransfer effectively induced a cellular response against neoplastic cells characterized mainly by the recruitment of T-lymphocytes and macrophages and a fibrotic proliferation with reduction of microvessels.
Keywords: histopathology, interleukin-12, elektroporation, electrochemotherapy, immune cells
Published in DiRROS: 31.05.2024; Views: 83; Downloads: 63
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Abstract: Background. Non-small cell lung cancer (NSCLC) is the most common type of lung cancer and remains an important cause of cancer death worldwide. Platinum-based chemotherapy (PBC) for NSCLC can modify outcome while the risk of cardiotoxicity remains poorly researched. We aimed to evaluate the incidence and severity of cardiac injury during PBC in patients with NSCLC and to identify patients at risk. Methods. This was a single-centre, prospective, observational study of patients with early and advanced stage NSCLC referred for PBC. In addition to standard care, patients were examined and evaluated for cardiotoxicity before the first dose (visit 1), at the last dose (visit 2) and 6 months after the last dose of PBC (visit 3). Cardiotoxicity (at visit 2 and 3) was defined as increase in the ultrasensitive troponin T, N-terminal pro-B type natriuretic peptide or decrease in left ventricular ejection fraction (LVEF). Results. Overall, 41 patients (mean age 61 +/- 9; 54% men; 68% advanced lung cancer) were included. The median number of PBC cycles was 4. During the study period, there were no incidents of heart failure, and 3 deaths caused by tumour progression were recorded. The mean values of biomarkers and LVEF did not change significantly (p > 0.20). However, 10 (25%) had cardiotoxicity which was independently associated with a history of ischemic heart disease (p = 0.026). Conclusions. In NSCLC, cardiac assessment and lifestyle modifications may be pursued in patients with a history of cardiac disease and in patients with longer life expectancy.
Published in DiRROS: 10.05.2024; Views: 130; Downloads: 68
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