Comparative Study Of Cytotoxic Effects Research Articles

A Comparative Study of Cytotoxic Effect in Three Vitis vinifera L. Varieties: King Ruby, Thompson and Crimson against A-549 lung cancer cell line

A Comparative Study of Cytotoxic Effect in Three Vitis vinifera L. Varieties: King Ruby, Thompson and Crimson against A-549 lung cancer cell line

Comparative Study of the Cytotoxic Effect of Silver Nanoparticles on Human Lymphocytes and HPB-ALL Cell Line: As an In Vitro Study

Background: Cancer is currently the second leading cause of death worldwide that is originated from cell growth and proliferation without control. Acute lymphoblastic leukemia (ALL) is one of the types of leukemia that affects lymphocyte maturation and it is common among children. Silver nanoparticles are considered one of the targeted chemotherapy methods by creating cytotoxicity. Objectives: In this research, a comparative study of cytotoxic effect of silver nanoparticles was evaluated on human lymphocytes and HPB-ALL cell line as an in vitro study. Methods: In this experimental study, lymphocytes and HPB-ALL cell line were exposed to silver nanoparticles at RPMI 1640 medium culture in order to assess toxicity for 24 hours. To this aim, MTT assay was used to evaluate the toxicity of the silver nanoparticles. DNA fragmentation and apoptosis were evaluated by Gel Electrophoresis and Flow Cytometry, respectively. Moreover, quantitative PCR was performed on bax, bcl-2, and caspase-9 genes. Results: The results of MTT assay showed IC50 values of silver nanoparticles were 5.87 and 2.68 μg/mL for lymphocytes and HPB-ALL cell line, respectively. The results showed that silver nanoparticles could split DNA of the HPB-ALL cell line more than DNA of the lymphocytes during DNA fragmentation. Flow Cytometry results indicated that the early apoptosis was 6.04% and 22.75% in lymphocytes and HPB-ALL cell line, respectively. Moreover, Q-PCR results showed a significant up-regulation of caspase-9 and bax genes and downregulation of bcl-2 gene in comparison to the control group. Conclusions: The silver nanoparticles had cytotoxic effects on the lymphocytes and HPB-ALL cell line. The results showed that the silver nanoparticle had a significant cytotoxic effect on HPB-ALL cell line.

Comparative study of cytotoxic effects induced by environmental genotoxins using XPC- and CSB-deficient human lymphoblastoid TK6 cells

BackgroundThe human genome is constantly exposed to numerous environmental genotoxicants. To prevent the detrimental consequences induced by the expansion of damaged cells, cellular protective systems such as nucleotide excision repair (NER) exist and serve as a primary pathway for repairing the various helix-distorting DNA adducts induced by genotoxic agents. NER is further divided into two sub-pathways, namely, global genomic NER (GG-NER) and transcription-coupled NER (TC-NER). Both NER sub-pathways are reportedly involved in the damage response elicited by exposure to genotoxins. However, how disruption of these sub-pathways impacts the toxicity of different types of environmental mutagens in human cells is not well understood.ResultsTo evaluate the role of NER sub-pathways on the cytotoxic effects of mutagens, we disrupted XPC and CSB to selectively inactivate GG-NER and TC-NER, respectively, in human lymphoblastoid TK6 cells, a standard cell line used in genotoxicity studies. Using these cells, we then comparatively assessed their respective sensitivities to representative genotoxic agents, including ultraviolet C (UVC) light, benzo [a] pyrene (B(a)P), 2-amino-3,8-dimethylimidazo [4,5-f] quinoxaline (MeIQx), 2-amino-1-methyl-6-phenylimidazo [4,5-b] pyridine (PhIP), γ-ray, and 2-acetylaminofluorene (2-AAF). CSB−/− cells exhibited a hyper-sensitivity to UVC, B(a)P, and MeIQx. On the other hand, XPC−/− cells were highly sensitive to UVC, but not to B(a)P and MeIQx, compared with wild-type cells. In contrast with other genotoxins, the sensitivity of XPC−/− cells against PhIP was significantly higher than CSB−/− cells. The toxicity of γ-ray and 2-AAF was not enhanced by disruption of either XPC or CSB in the cells.ConclusionsBased on our findings, genetically modified TK6 cells appear to be a useful tool for elucidating the detailed roles of the various repair factors that exist to combat genotoxic agents, and should contribute to the improved risk assessment of environmental chemical contaminants.