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Background: The optimal radiobiological model, which assesses the biological effects of novel radiotherapy techniques that concurrently modify multiple physical factors, has not yet been defined. This study aimed to investigate the impact of intensity‐modulated radiotherapy (IMRT) and volumetric‐modulated arc therapy (VMAT) on cellular response in head and neck cancer and melanoma models. Methods: Clonogenic analysis, DNA double‐strand break analysis, apoptosis, and cell cycle analysis were performed on cancer stem cell models, cancer models, and normal tissue cell models to assess radiation sensitivity. Results: The segmented radiation approach used in IMRT applications enhanced radiosensitivity and cytotoxicity in the cancer models, while changes in dose rate had varying effects on cytotoxicity depending on the tumor cell type. VMAT increased cellular resistance, favoring treatment outcomes. Conclusions: The biological processes were influenced differently by dose rate, IMRT, and VMAT depending on the tumor cell type. The selection of the most appropriate technique is crucial in representing new radiotherapy approaches. The obtained data can serve as a model to address clinical questions in daily practice. The integration of non‐standard outcomes with standard applications should be considered in clinical settings. [ABSTRACT FROM AUTHOR]

Origanum sipyleum is used in folk medicine due to its anti-inflammatory, antimicrobial, and antioxidant properties. Ponatinib, an effective tyrosine kinase inhibitor in the treatment of chronic myeloid leukemia (CML), has severe side effects. Thus, we aimed to determine a novel herbal combination therapy that might not only increase the anti-leukemic efficacy but also reduce the dose of ponatinib in targeting CML cells. Origanum sipyleum was extracted with methanol (OSM), and secondary metabolites were determined by phytochemical screening tests. The cytotoxic effects of OSM on K562 cells were measured by WST-1 assay. Median-effect equation was used to analyze the combination of ponatinib and OSM (p-OSM). Apoptosis, proliferation, and cell-cycle were investigated by flow-cytometry. Cell-cycle-related gene expressions were evaluated by qRT-PCR. OSM that contains terpenoids, flavonoids, tannins, and anthracenes exhibited cytotoxic effects on K562 cells. The median-effect of p-OSM was found as synergistic; OSM reduced the ponatinib dose ∼5-fold. p-OSM elevated the apoptotic and anti-proliferative activity of ponatinib. Consistently, p-OSM blocked cell-cycle progression in G0/G1, S phases accompanied by regulations in TGFB2, ATR, PP2A, p18, CCND1, CCND2, and CCNA1 expressions. OSM enhanced the anti-leukemic activity of ponatinib synergistically via inducing apoptosis, suppressing proliferation, and cell-cycle. As a result, OSM might offer a potential strategy for treating patients with CML. [ABSTRACT FROM AUTHOR]

LncRNAs are associated with malignancies with their tumor suppressor/oncogenic properties. Although many studies are conducted related to the mechanism of action for dasatinib and ponatinib in chronic myeloid leukemia (CML), their comparative effects on lncRNA expressions are largely unknown. Hence, we aimed to define the lncRNAs involved in the treatment of CML with dasatinib and ponatinib. We measured the cytotoxicities of dasatinib/ponatinib with CCK-8 assay and identified differentially expressed lncRNAs (DEL) by qRT-PCR. We determined the principal functions of DELs by Ingenuity Pathway Analysis (IPA) and performed gene ontology (GO) analysis for apoptosis and anti-proliferation-related lncRNAs. Apoptotic and anti-proliferative activities of dasatinib/ponatinib were confirmed by flow-cytometry. In K562 cells, dasatinib/ponatinib re-regulated lncRNAs which were dysregulated in leukemia. DELs after treatment (forty with dasatinib, thirty-seven with ponatinib) were related to increased cell death; decreased cell viability, proliferation, tumor growth, invasion, migration. Dasatinib-mediated network was related to cancer, hematological disease while ponatinib-mediated network was associated with cancer, cell death/survival, cell-to-cell signaling/interaction. Both treatments predicted activation of IFNγ, IL1β, TNF as upstream regulators, specially this effect was higher in dasatinib. Comparison analysis showed that ponatinib was predicted more effective in cell death of tumor cell line than dasatinib. We confirmed that ponatinib was more potent than dasatinib to induce apoptosis and inhibit proliferation of CML cells, in consensus with IPA and GO analysis results. LncRNAs are specifically involved in anti-leukemic activities of dasatinib and ponatinib. Our findings will contribute to understanding signalization occurring in CML cells after standard treatments. [ABSTRACT FROM AUTHOR]