Synthetic vaccines utilize viral signatures to trigger immune responses. Although the immune responses raised against the biochemical signatures of viruses are well characterized, the mechanism of how they affect immune response in the context of physical signatures is not well studied. In this work, we investigated the ability of zero- and one-dimensional self-assembled peptide nanostructures carrying unmethylated CpG motifs (signature of viral DNA) for tuning immune response. These nanostructures represent the two most common viral shapes, spheres and rods. The nanofibrous structures were found to direct immune response towards Th1 phenotype, which is responsible for acting against intracellular pathogens such as viruses, to a greater extent than nanospheres and CpG ODN alone. In addition, nanofibers exhibited enhanced uptake into dendritic cells compared to nanospheres or the ODN itself. The chemical stability of the ODN against nuclease-mediated degradation was also observed to be enhanced when complexed with the peptide nanostructures. In vivo studies showed that nanofibers promoted antigen-specific IgG production over 10-fold better than CpG ODN alone. To the best of our knowledge, this is the first report showing the modulation of the nature of an immune response through the shape of the carrier system.

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Electrochemotherapy is the usage of electroporation to introduce chemotherapeutic drugs through membrane pores into target cells for cancer treatment. The effectiveness of chemotherapeutic drugs would be increased dramatically when they are used in electrochemotherapy than standard chemotherapy. In the present study, we investigated the effects of cisplatin treatment with electroporation on human SH-SY5Y neuroblastoma cells. SH-SY5Y cells were treated with different concentrations (0.15-24 µg/mL) of cisplatin and then exposed to 1500 volts per centimeter (V/cm), 100 microseconds (µs) pulse duration, and 1 Hertz (Hz) electric pulses. Cisplatin alone showed a dose-dependent effect on cell viability. On the other hand, cisplatin + electroporation treatment was more effective than cisplatin treatment alone. Lower doses of cisplatin treatment with electroporation was as effective as higher doses of cisplatin treatment without electroporation. These results indicated that cisplatin cytotoxicity was potentiated after exposure of cells to high intensity electric pulses and low doses of cisplatin can be used with electroporation in the treatment of neuroblastoma.

This study examines the effects of a 2.1-GHz WCDMA-modulated microwave (MW) radiation on apoptotic activity and mitochondrial membrane potential (ΔΨm) in MCF-7 cells. The cells were exposed to the MW at a specific absorption rate (SAR) of 0.528 W/kg for 4 or 24 h. The antiproliferative effect of MW exposure was determined by the MTT test. Cytochrome-c and p53 levels were determined by an ELISA method. The relative ΔΨm was analysed by JC-1 staining using flow cytometer. Apoptotic rate of the cells was measured by Annexin-V-FITC staining. All assays were performed after certain time of incubations (15 min-4 h) following MW exposure. MW-exposed cells showed a significant decrease in viability when compared to unexposed cells. A significantly larger decrease was observed after longer exposure. The percentage of apoptotic cells, amount of cytochrome-c, and relative ΔΨm were significantly higher in MW-exposed cells. The percent of apoptotic cells and relative ΔΨm in 24 h MW-exposed group was significantly higher than those in 4 h MW-exposed group. However, no significant change was observed in p53 levels. These results demonstrated that exposure to 2.1-GHz WCDMA-modulated MW radiation caused hyperpolarization of mitochondria that in turn induced apoptosis in MCF-7 cells.

Parkinson’s disease (PD) is a highly prevalent neurodegenerative disorder, often associated with oxidative stress-induced transcriptional changes in dopaminergic neurons. Phenolic antioxidants, oleuropein (OLE) and rutin (RUT) have attracted a great interest due to their potential to counteract oxidative protein aggregation and toxicity. This study aimed at examining the effects of OLE and RUT against 6-OHDA-induced stress response in rat pheochromocytoma cells. When differentiated PC12 cells were exposed to oxidative stress composer 6-OHDA (100 μM, 8 h), a decreased mitochondrial membrane potential (ΔΨm) was observed along with a significant loss of cell viability and apoptotic nuclear changes. Exposure to 6-OHDA resulted in unfolded protein response (UPR) in differentiated PC12 cells as evidenced by an increased level of endoplasmic reticulum (ER)-localized transmembrane signal transducer IRE1α, adaptive response proteins ATF-4 and proapoptotic transcription factor CHOP. OLE or RUT pretreatment (24 h) at low doses (1–50 μM) protected the differentiated PC12 cells from 6-OHDA-induced cytotoxicity as assessed by increased viability, improved ΔΨm and inhibited apoptosis, whereas relatively high doses of OLE or RUT (>50 μM) inhibited cell growth and proliferation, indicating a typical hormetic effect. In hormetic doses, OLE and RUT up-regulated 6-OHDA-induced increase in IRE1α, ATF-4 and inhibited CHOP, PERK, BIP and PDI. 6-OHDA-activated XBP1 splicing was also inhibited by OLE or RUT. The presented results suggest that neuroprotection against 6-OHDA-induced oxidative toxicity may be attributable to neurohormetic effects of OLE or RUT at low doses through regulating mitochondrial functions, controlling persistent protein misfolding, activating and/or amplificating the adaptive response-related signaling pathways, leading to UPR prosurvival output.

Objectives The aim of this study is to investigate the effects of radiofrequency radiation (RFR) on apoptosis, proliferation, stress response, and inflammation markers in colorectal cancer cells. Methods We tested the effects of intermittent exposure to RFR at different frequencies on two different colorectal cancer cell lines; HCT-116 and DLD-1. Protein levels were subsequently analyzed by ELISA. Results RFR led to a decrease in P53, p-P53, p-P38, and p-IkB levels in HCT-116 cells, while leading to an increase in BAD, p-BAD, p-STAT3,NF-κB levels. Two thousand one hundred Megahertz of RFR altered the P53, BAD, and NF-ΚB expression in HCT-116 cells. P53, p-P53, BAD, p-BAD, NF-κB, p-NF-κB, p-P38, p-SAPK/JNK, p-STAT3, and p-IkB levels increased after exposure to RFR at 900 and 2,100 MHz in DLD-1 cells. Unlike HCT-116 cells, 1,800 MHz of RFR was reported to have no effect on DLD1 cells. Conclusions RFR increased apoptosis and inflammatory response in HCT116 cells, while lowering the active P38 and active P53 levels, which are indicators of poor prognosis in several cancers. Genetic differences, such as P53 mutation (DLD-1), are critical to the cell response to RFR, which explains the reason why scientific studies on the effects of RFR yield contradictory results.

In this study, the effect of RNAi on HBV replication was observed in a cell culture model, HepG2 2.2.15 cell line, which supports human HBV ayw replication and expression. Aim of the study was to investigate effects of shRNAs (small hairpin RNAs) targeting hepatitis B virus mRNAs on the viral replication in HepG2 2.2.15 cells. We selected three target HBV mRNA regions with different putative secondary structures to test whether the secondary structure of RNA may affect the inhibition efficacy on the target HBV RNA. Three HBV-specific siRNAs (small interfering RNA) were designed targeting X (1689-1708), Core (2229-2248) and S (765-784 nt) transcripts. HepG2 2.2.15 cells were transfected with shRNA expressing plasmids, P765, P2229 and P1689 targeting S, core and X region, respectively or a mock plasmid targeting lacZ gene. The culture media was collected throughout six days after transfection and analyzed by real-time PCR. Viral DNA production was suppressed for 7 days. The HBV DNA levels were decreased by 73, 72 and 79% with P765, P2229 and P1689 vectors, respectively. In conclusion, the shRNAs designed for X, core and S regions, specifically and significantly suppressed HBV DNA. siRNAs potentially may be used in treatment of hepatitis B.

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