Evaluation of the PTEN and circRNA-CDR1as Gene Expression Changes in Gastric Cancer and Normal Cell Lines Following the Exposure to Weak and Moderate 50 Hz Electromagnetic Fields

Abstract

Background: Attention to the electromagnetic exposure as a targeted tumor therapy has been recently increasing. Objectives: The aim of the current study was to investigate the effect of continuous and discontinuous electromagnetic fields on cell viability as well as phosphatase and tensin homolog (PTEN) and circular (circ)-RNA CDR1as genes expression in the normal and gastric cancer (GC) cell lines. Methods: After preparing gastric cancer cell lines (AGS) and normal cells (HU02 line), they were exposed to magnetic flux densities of 0.25, 0.5, 1, and 2 mT continuously and discontinuously (1h on/1h off) for 18 hours. The 3-(4,5-dimethylthiazoyl-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to evaluate cell viability. In addition, after designing the primers, the expression of the PTEN and circ-CDR1as genes was studied using the real-time polymerase chain reaction (real-time-PCR) technique. The results were analyzed using SPSS software version 25. Results: The exposed normal and tumor cells to discontinuous electromagnetic fields resulted in increasing of cell survival rate in both normal and tumor cells. In contrast, the exposure of continuous electromagnetic field showed no effect on the viability of the normal and tumor cells at intensities of 0.25, 0.5, and 1 mT. The electromagnetic field showed a significant effect on the expression of the circ-CDR1as gene and this effect depended on the intensity of the electromagnetic field used and the cell type. We have found that the activity of PTEN gene in the normal and tumor cells increased and decreased with increasing intensity of discontinuous electromagnetic field, respectively. Conclusions: In general, the effect of electromagnetic field on gastric cancer seems to depend on the kind of exposure as well as an extent of intensity and can be used for cancer therapeutic purposes. However, more research is needed on this subject.

Pulsed Magnetic Fields Cause hes1 and hsa-Circ-0068530 Expression Changes in Gastric Cancer Cell Line and Human Normal Fibroblast Cell Line

“…Figure 1 shows the exposure system that included a solenoid cylinder explained in our previous study (27,28). The cells were exposed to ELF magnetic flux densities of 0.25, 0.5, 1, and 2 mT for 18 h. The control and exposure cells were incubated in a constant condition of temperature, humidity, and CO 2 (26).…”

“…The primer sequences are listed in Table 1. The 2-∆∆CT method was applied to determine relative changes in gene expression in samples (26,29). Each experiment consisted of six separated flasks of cells.…”