An Inventive Report of Inducing Apoptosis in Non-Small Cell Lung Cancer (NSCLC) Cell Lines by Transfection of MiR-4301.

BACKGROUND: Based on recent studies, new therapeutic strategies have been developed for cancer treatment using microRNAs (miRNAs). With this view, miRNAs manipulating techniques can be considered as novel therapeutic prospects for cancer treatment. In this study, we evaluated the expression of miR-4301 in human lung cancer cell lines and investigated its potential role in cell proliferation and tumor suppression on Non-Small Cell Lung Cancer (NSCLC) cells. METHODS: We used quantitative Real-Time Polymerase Chain Reaction (qRT-PCR) to examine the level of miR- 4301 expression in human lung cancer cell lines (A549, QU-DB) and non-malignant lung epithelial cells (HFLF-PI5). Then, we investigated the effect of miR-4301 by transfecting it into these cell lines and probing for cancer cell viability and apoptosis using the MTT assay, flow cytometry and immunofluorescence staining. RESULTS: Our results showed that the expression level of miR-4301 was significantly reduced in human lung cancer cell lines (P<0.001). When miR-4301 was transfected in lung cancer cells, their cell proliferation was suppressed and apoptosis induced. This decline in cell survival was confirmed by the MTT assay. Transfection of miR-4301 caused an increase in early and late apoptotic cells in all lung cancer cell lines tested. CONCLUSIONS: Our findings show that miR-4301 may act as a lung cancer suppressor through targeting of proteins involved in cell proliferation and survival. For this reason, targeting miR-4301 may provide a new strategy for the diagnosis and treatment of patients with this deadly disease. This article is protected by copyright. All rights reserved.

Structural characterization of a rhamnolipid-type biosurfactant produced by Pseudomonas aeruginosa MR01: enhancement of di-rhamnolipid proportion using gamma irradiation.

We previously reported that MR01, an indigenous strain of Pseudomonas aeruginosa, was able to produce a rhamnolipid-type biosurfactant. Here, we attempted to define the structural properties of this natural product. The analysis of the extracted biosurfactant by thin-layer chromatography (TLC) revealed the presence of two compounds corresponding to those of authentic mono- and di-rhamnolipid. The identity of two structurally distinguished rhamnolipids was confirmed by 1H and 13C nuclear magnetic resonance (NMR) spectroscopy. Liquid chromatography/mass spectrometry (LC/MS) of extracted biosurfactant revealed up to seventeen different rhamnolipid congeners. Further quantification showed di-rhamnolipids as the major compound (77.2%), while monorhamnolipids comprising a smaller proportion (22.8%) of MR01 biosurfactant. Rha-Rha-C10-C10 was verified as the major component of the MR01 biosurfactant (35.93%). Cytotoxic activity of MR01 biosurfactant against human cancer Hela cells showed an excellent inhibitory effect of 5µg/ml. An isolated mutant strain (MR01-C) created by Gamma ray irradiation demonstrated more than one and a half-fold biosurfactant production and activity compared with the parent strain. Analysis of the biosurfactant produced by MR01-C showed the magnitude of di-rhamnolipids in the sample increased up to 88.6% (∼15% higher than control) and the quantity of Rha-Rha-C10-C10 increased to 52.08% (∼45% higher than control).

Mercury absorption by Pseudomonas fluorescens BM07 grown at two different temperatures.

Pseudomonas fluorescens BM07 was characterized as a producer of cold-induced biopolymer by decreasing the temperature down to as low as 10 degrees C. It was previously shown that the synthesis of BM07 biopolymer was inhibited at 30 degrees C. The present study was conducted to investigate the biosorption of mercury (Hg2+) ions on the BM07 cells grown on M1 minimal medium at two temperatures (10 degrees C and 30 degrees C). The effects of various factors including pH, contact time, initial concentration of metal and cell biomass on the biosorption yield were also studied. Study of the effect of pH on mercury removal indicated that the metal biosorption increased with increasing pH from 3.0 to 7.0. The optimum adsorption pH value was found to be 7.0. Our results showed that, at optimum pH, BM07 cells were able to uptake the mercury up to 102 and 60 mg Hg2+/g dry biomass for 10 degrees C and 30 degrees C grown cells respectively. The removal capacity of cells increased when the cell biomass concentrations increased. The maximum removal efficiency was obtained when cells concentration was 0.83 mg dry biomass/ml for both conditions. The initial metal ion concentration significantly influenced the equilibrium metal uptake and adsorption yield. The equilibrium data were analyzed using Langmuir adsorption model. The qmax was 62.9 and 82.25 mg Hg2+/g dry biomass for cells grown at 30 degrees C and 10 degrees C respectively. The results suggest that, the existence of residual cold-induced biopolymer on the external surface of cells may play an important role in biosorption efficiency, as P. fluorescens BM07 cells which were grown at 10 degrees C under similar conditions showed higher efficiency to biosorbe mercury than non-polymer producing cells grown at 30 degrees C.