Evaluation of the effect of intensity-modulated radiotherapy (IMRT) and volumetric-modulated arc radiotherapy (VMAT) techniques on survival response in cell lines with a new radiobiological modeling.

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.

Origanum Sipyleum Methanol Extract in Combination with Ponatinib Shows Synergistic anti-Leukemic Activities on Chronic Myeloid Leukemia Cells.

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.

Comparative expression analysis of dasatinib and ponatinib-regulated lncRNAs in chronic myeloid leukemia and their network analysis.

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, IL1ß, 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.

Effect of CCT137690 on long non-coding RNA expression profiles in MCF-7 and MDA-MB-231 cell lines.

Long non-coding RNAs (lncRNAs) are involved in a range of biological processes, such as cellular differentiation, migration, apoptosis, invasion, proliferation, and transcriptional regulation. The aberrant expression of lncRNAs plays a significant role in several cancer types. Aurora kinases are increasingly expressed in various malignancies; accordingly, the inhibition of these enzymes may represent a novel approach for the treatment of various cancers. CCT137690, an Aurora kinase inhibitor, displays an anti-proliferative activity in human cancer cell lines. The aim of the present study was to investigate the anti-proliferative and cytotoxic effects of CCT137690 on estrogen receptor (ER)-positive human breast cancer cell line (MCF-7) and ER-negative human breast cancer cell line (MDA-MB-231). In addition, this study was targeted toward determining the changes induced in lncRNA expression levels following the initiation of Aurora kinase inhibitor treatment. The cytotoxic effects of CCT137690 were determined by means of the xCELLigence system. Furthermore, the anti-proliferative role of CCT137690 in breast cancer was investigated by checking the changes in lncRNA expression profiles using quantitative reverse-transcription polymerase chain reaction (qRT-PCR). The half-maximal inhibitory concentrations (IC50) of CCT137690 were determined as 4.5 µM (MCF-7) and 7.27 µM (MDA-MB-231). Several oncogenic lncRNAs (e.g., PRINS, HOXA1AS, and NCRMS) were downregulated in both ER-negative and ER-positive cell lines. On the other hand, tumor suppressor lncRNAs (e.g., DGCR5 and IGF2AS) were upregulated in the ER-positive cell line. After CCT137690 treatment, HOXA11AS and PCAT-14 lncRNAs were downregulated in the ER-positive cell lines. In addition, MER11C, SCA8, BC200, HOTAIR, PCAT-1, UCA1, SOX2OT, and HULC lncRNAs were downregulated in the ER-negative cell lines. The results of the present study indicated that Aurora kinase inhibitor CCT137690 could be a potential anti-cancer agent for breast cancer treatment.

Investigation of the synergistic effects of paclitaxel and herbal substances and endemic plant extracts on cell cycle and apoptosis signal pathways in prostate cancer cell lines.

Paclitaxel, which isolated from Taxus brevifolia, is recently started to be used against prostate cancer treatment and it is a very effective compound against cancer. In this study, we aimed to test the synergistic effect of two plant active compounds (sulphoraphane (SFN) and silymarin (SILY)) and several endemic plant species from Turkey (such as Phlomis leucophracta, Rubia davisiana, Alkanna tinctoria), which are known to have anticarcinogenic effect on androgen-independent PC3 and DU145, and androgen-dependent VCaP prostate cancer cell lines, with paclitaxel on the expression of cell cycle signaling and apoptosis regulator genes. Herbal substances and endemic herbal extracts were combined with Paclitaxel drug. IC50 doses were identified as real-time online. The most effective synergistic doses were determined according to isobologram analysis. The apoptotic effects of effective combined doses were evaluated by TUNEL, Annexin V, and JC-1 methods. Apoptotic and/or cell cycle arrest effects of confirmed combined doses on the expression of genes in these pathways were assessed by real-time online. Endemic plant extracts (Alkanna tinctoria, Phlomis leucophracta and Rubia davisiana, IC50 < 220 µg/ml) and herbal substances (SILY, and SFN IC50 < 130 µM) indicated antiproliferative and apoptotic effects in prostate cancer cell lines. They testified to the synergistic effect of paclitaxel with endemic plant extracts (Combination Index CI, ED50 < 0.41). The combinations, which indicate the synergistic effect was increased to the Bax/Bcl­2 ratio by suppressing Bcl­2 gene expression into the prostate cancer cell lines. Besides, they increased the expression of TNFRSF10A, TNFRSF1A, CHEK1, CDKN1A, CDKN2B, CDK8, CDKN3 and CASP14 and decreased BAD, CDK5RAP1, CDC20, cyclin H, CDK5RAP1, CDC20. The effective doses of paclitaxel were reduced and G2/M arrest was induced by the endemic plant extracts and herbal substances that indicate a synergistic effect with paclitaxel. By using different combination of herbal extracts or active substances with paclitaxel, more economical and efficient treatment strategies can be developed.

Analysis of long non-coding RNA (lncRNA) expression in hepatitis B patients.

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.

Antileukemic effect of paclitaxel in combination with metformin in HL-60 cell line.

Acute promyelocytic leukemia (APL) is a subtype of AML that is a mixture of hematological malignancy, characterized by a specific translocation t(15;17). The using of all-trans retinoic acid (ATRA) with arsenic trioxide (ATO) or chemotherapeutic agents or both of these agents, composes main treatment strategy of APL. While it is possible to achieve success in treatment of low-risk APL with current treatment regimens, such success is not mentioned in high-risk APL. So, it may develop new approaches for treatment regimens for high-risk APL. In the present study, we aimed to investigate the effects of combinational of a classic anticancer agent paclitaxel and antidiabetic agent metformin on HL-60 APL cell line. The combination dose of paclitaxel and metformin was determined by WST-1 analysis. The effect of combinational dose on apoptosis was assessed in fluorescence microscope after using AnnexinV-EGFP Apoptosis and JC-1 Assay Kit. The effect of combinational dose on cell cycle, apoptosis and differentiation, and signaling pathways were determined investigating gene expression changes by using real time qRT-PCR. The combinational dose of paclitaxel and metformin was determined as 4.8nM and 398.7µM for 72h, respectively. The combination dose significantly increased apoptosis for 48h. In expression changes of genes associated cell cycle, apoptosis, cytokines, co-stimulator molecules, NF-kB and MAP/MAPK pathways, TLRs (Toll-like receptors) were found to be decreased or increased to provide apoptosis or differentiation. Consequently, we suggest that the combination of paclitaxel and metformin can be used as an option assessable for development of new treatment strategies for APL.