Evaluating the Radiosensitization Effect of Hydroxyapatite Nanoparticles on Human Breast Adenocarcinoma Cell Line and Fibroblast

Background:

Nanohydroxyapatite (nHAP) exhibit anti-proliferative effects on various cancer cells. However, to date, there are only a few studies on the radiosensitization effect of nHAP. The present study aimed to investigate the possible enhancement of the radiosensitization effect of nHAP on human breast adenocarcinoma cancer (MCF-7) and fibroblast.

Methods:

nHAP was extracted from fish scales using the thermal alkaline method and characterized at Babol University of Medical Sciences (Babol, Iran) in 2017. The anti-proliferative and the radiosensitization effects of nHAP were investigated by 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-Diphenyltetrazolium Bromide (MTT), clonogenic assay, and apoptosis assay. MCF-7 cells and fibroblasts were incubated with different concentrations of nHAP and at different periods. The MTT solution was added and the absorbance was measured at 570 nm. The MCF-7 cells were exposed to 0, 1.5, 3.5, and 5 Gy X-ray irradiation and incubated for 10-14 days. The data were compared using the one-way analysis of variance (ANOVA) followed by the post hoc tests (Tukey’s method).

Results:

The results showed that nHAP significantly inhibited the growth of MCF-7 cells compared with controls (P<0.001), but the difference was not statistically significant for fibroblasts (P=0.686 at 400 µg/mL at 72 hours). After 48 hours, the proliferation of MCF-7 cells and fibroblasts was inhibited by about 81% and 34% at 400 µg/mL concentration, respectively. The radiosensitization enhancement factor for MCF-7 cells and fibroblasts at a dose of 3.5 Gy and 100 μg/mL concentration were 1.87 and 1.3, respectively.

Conclusion:

nHAP can be considered as a breast cancer radiosensitization agent with limited damage to the surrounding healthy tissue.

Preparation and characterization of marine mineralized ASC nanocomposites through biomineralization

Mineralized collagen provides new solutions in the manufacture of porous scaffolds for tissue engineering. In this research, the use of biomimetic mineralization, the process of mineralization of acid soluble collagen (ASC) type I extracted from white fish (Rutilus frisii kutum) scales, in a body simulated fluid (SBF) in the presence and absence of an anionic surfactant, sodium dodecyl benzene sulphonate (SDBS) was thoroughly investigated. The formation of β-tricalcium phosphate (β-TCP) nanocrystals in mineralized nanocomposites was detected by XRD, TGA, and FT-IR techniques. The denaturation temperature (T_d) of mineralized ASC was determined at 42.87 °C without surfactant, and at 70.2 °C with surfactant using DSC technique, which indicated a higher thermal stability of ASC without the SDBS surfactant. TEM images illustrated that the formation of β-TCP crystals on collagen nano-fibrils was in an irregular form in the absence of surfactant while it was more regular and in the form of rectangular sheets in the presence of surfactant. The results of UV/Vis spectrophotometer for turbidity measurements during the initial step of biomineralization revealed that SDBS while accelerating the self-assembly process of collagen nano-fibrills, delayed the process of nucleation and the growth of calcium phosphate nanocrystals by increasing the kinetic energy barrier.

The evaluation of radio-sensitivity of mung bean proteins aqueous extract on MCF-7, hela and fibroblast cell line

PURPOSE

Breast cancer is one of the most common malignant tumors in women all over the world. Many of these women resist the common treatments. Therefore, it is important to find new products to increase the efficacy of the treatment process. Legume beans, with their various pharmacological properties, can be regarded as a sensitizer when they are combined with radiation. The present study strove to survey the radio-sensitivity effect of proteins isolated from mung bean aqueous extract on the human breast adenocarcinoma cell line (MCF-7), human cervical cancer cells (Hela) and the human dermal fibroblast cell line.

MATERIALS AND METHODS

The mung bean aqueous extract was partially purified by ammonium sulfate. At first, various concentrations of the extracts were used to evaluate the inhibitory activity by MTT cell proliferation assay.

RESULTS

The results showed that MCF-7 cells and Hela cells were inhibited by an IC₅₀ value of less than 250 and 411 µg/ml, respectively, but it proved to have a proliferation effect on the fibroblast cells. Then, the cells were incubated with 250 µg/ml extract and exposed to 2, 4, and 6 Gy of X-ray radiation. The percentage of the cell survival was investigated through MTT and the clonogenic assay. Apoptosis was measured using acridine orange/ethidium bromide staining. The results demonstrated that the treated MCF-7 cells and Hela cells had significant radio-sensitivity compared with the results of the control group in radiation dose manner in all MTT, clonogenic, and apoptosis assays. In contrast, the treated fibroblast showed a protective effect against radiation.

CONCLUSION

The results suggest that mung bean proteins have the capacity to be regarded as a radio-sensitizer for breast cancer. Our results also indicated that it could be worth to investigate on mung bean proteins further and they should be tested in animal models for being treated in radiotherapy.

Application of FT-IR spectroscopy on breast cancer serum analysis

Breast cancer is regarded as the most malignant tumor among women throughout the world. Therefore, early detection and proper diagnostic methods have been known to help save women's lives. Fourier Transform Infrared (FT-IR) spectroscopy, coupled with PCA-LDA analysis, is a new technique to investigate the characteristics of serum in breast cancer. In this study, 43 breast cancer and 43 healthy serum samples were collected, and the FT-IR spectra were recorded for each one. Then, PCA analysis and linear discriminant analysis (LDA) were used to analyze the spectral data. The results showed that there were differences between the spectra of the two groups. Discriminating wavenumbers were associated with several spectral differences over the 950-1200cm^-1(sugar), 1190-1350cm^-1 (collagen), 1475-1710cm^-1 (protein), 1710-1760cm^-1 (ester), 2800-3000cm^-1 (stretching motions of -CH₂ & -CH₃), and 3090-3700cm^-1 (NH stretching) regions. PCA-LDA performance on serum IR could recognize changes between the control and the breast cancer cases. The diagnostic accuracy, sensitivity, and specificity of PCA-LDA analysis for 3000-3600cm^-1 (NH stretching) were found to be 83%, 84%, 74% for the control and 80%, 76%, 72% for the breast cancer cases, respectively. The results showed that the major spectral differences between the two groups were related to the differences in protein conformation in serum samples. It can be concluded that FT-IR spectroscopy, together with multivariate data analysis, is able to discriminate between breast cancer and healthy serum samples.

The use of antibacterial activity of ZnO nanoparticles in the treatment of municipal wastewater

Nanotechnology holds great potential in advanced water and wastewater treatment to improve treatment efficiency. Zinc oxide nanoparticles (ZnO NPs) have received considerable attention due to their unique antibacterial activities toward various microorganisms that are commonly found in the environment. In the present study, ZnO NPs were synthesized through both mechano-chemical and sol-gel methods. The synthesized ZnO NPs were characterized through X-ray diffraction and transmission electron microscopy techniques. Then, their antibacterial activities against separated wastewater bacteria were evaluated by determining the zone inhibitor, the minimum inhibitory concentration, and the minimum bactericidal concentration. The results were compared with those obtained from wastewater after chlorine disinfection and ultraviolet (UV) disinfection. These studies demonstrated that the antibacterial activity of ZnO NPs depends on the type and the strain of bacteria. They have also demonstrated that the activity increases as the concentration of ZnO NPs increases. Overall, the experimental results suggest that ZnO NPs can potentially be an antibacterial reagent to treat wastewater. They can particularly be applied as a complementary method with UV disinfection. Thus, they can be developed as antibacterial agents to improve wastewater quality.

Density functional theory study of nitrogen-14 nuclear quadrupole coupling parameters of L-histidine: hydrogen-bonded system

The calculations of nitrogen-14 nuclear quadrupole parameters, nuclear quadrupole coupling constant, χ, and asymmetry parameter, η, of L-His were done in two distinct environments: one as a free fully optimized molecule, an isolated molecule with the geometrical parameters taken from X-ray, and the other in the orthorhombic and monoclinic solid states. The most probable interacting molecules with the central molecule in the crystalline phase were considered in the hexameric clusters to include hydrogen-bonding effects in the calculations. The computations were performed with PW91P86/6-31++G** and B3LYP6-31++G** methods using the Gaussian 98 program. The good agreement between the nitrogen-14 quadrupole parameters of the free His and imidazole molecules with their microwave available data demonstrates that the applied level of theory and the 6-31++G** basis set are suitable to obtain reliable electric field gradient values. In the solid state, the shifts of quadrupole coupling parameters from the monomer to the solid phase are reasonably well reproduced for the amino and imino sites of imidazole ring in a hexameric cluster. That implies the fact that the hexameric cluster worked effectively to generate the results which are compatible with the experiment. The quadrupole coupling constant values of -N(+) H(3) group are in fair agreement with the experiment. This discrepancy is due to the absences of vibrational effects and the rotation of -N(+) H(3) group around N-C(α) bond.

A simple method for preparation of immuno-magnetic liposomes

A simple and readily manoeuverable method for preparing immuno-magnetic liposomes that indigenously contain binding sites for attaching other molecules like antibodies on their exterior surface is described. In this method magnetic unilamellar vesicles are prepared from a mixture of phosphatidylcholine, cholesterol, small amounts of a linear chain aldehyde and colloidal particles of magnetic iron oxide, using a reverse phase evaporation technique. The aldehyde (dedecanal) molecules align themselves among the lipid molecules in the bilayer with their aldehyde groups exposed to the aqueous phase, allowing straight attachment of antibody molecules (human-antimouse IgG-FITC in this case) in one single step. The success of this approach is confirmed by fluorescence microscopy as well as binding of the resulting immuno-magnetic liposomes to their corresponding target cells.