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Abstract 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.

Long non-coding RNAs (lncRNAs) have been implicated in numerous biological processes, including epigenetic regulation, cell-cycle control, and transcriptional/translational regulation of gene expression. Differential expression of lncRNAs and disruption of the regulatory processes are recognized as critical steps in cancer development. The role of lncRNAs in hepatitis B virus (HBV) infection is not well understood. Here we analyzed the expression of 135 lncRNAs in plasma samples of 82 HBV patients (classified as chronic patients, inactive carriers, or resolved patients) at diagnosis and at 12 months of treatment in relation to control group (81 healthy volunteers). We also investigated the effect of small interfering RNA (siRNA)-mediated silencing of lincRNA-SFMBT2 on HBV-positive human liver cancer cell line. lncRNA expression was analyzed by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Chemically synthesized siRNAs were transfected into the cell lines using Lipofectamine 2000 Reagent (Thermo Fisher Scientific). HBV DNA and HBsAg and HBeAg were detected in transfected cultures by real-time PCR and ELISA, respectively, using commercial kits. We observed changes in lncRNA expression in all three HBV groups, compared to control group. Most notably, the expression of anti-NOS2A, lincRNA-SFMBT2, and Zfhx2as was significantly increased and expression of Y5 lncRNA was decreased in chronic HBV patients. A decreased Y5 expression and increased lincRNA-SFMBT2 expression were observed in inactive HBsAg carriers. The expression of HOTTIP, MEG9, and PCAT-32 was increased in resolved HBV patients, and no significant change in the expression of Y5 was observed, compared to control group. siRNA-mediated inhibition of lincRNA-SFMBT2 decreased the level of HBV DNA in human liver cancer cells. Further research is needed to confirm the prognostic as well as therapeutic role of these lncRNAs in HBV patients.