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Effects of extremely low-frequency electromagnetic fields (ELF-EMFs) on DNA damage in biological systems are still a matter of dispute. The aim of the present study was to investigate the possible effect of electromagnetic field exposure on DNA fragmentation in cells (blastomers) of mouse blastocysts. Eighty female NMRI mice were randomly divided into 2 groups of 40 animals each. The control group was left unexposed whereas the animals in the EMF-group were exposed to a 50-Hz EMF at 0.5 mT 4 h per day, 6 days a week for a duration of 2 weeks. After the 8(th) day of exposure, the female mice in both groups were superovulated (with injections of pregnant mare serum gonadotropin and human chorionic gonadotropin) and then mated overnight. At approximately 4 days after mating (102 h after the human chorionic gonadotropin treatment), blastocysts were obtained by flushing the uterus horns. The mean numbers of pregnant mice, blastocysts after flushing, blastomers within the blastocysts, and the DNA fragmentation index following staining in both groups were compared using statistical methods (SPSS, the Chi-square test, the Student's t-test and the Mann-Whitney U-test, P < 0.05). The results showed that the mean number of blastocysts after flushing was significantly decreased in the EMF-group compared to that of the control group (P < 0.03). The DNA fragmentation index was significantly increased in the EMF-group compared to control (10.53% vs. 7.14%; P < 0.001). However, there was no significant difference in the mean numbers of blastomers and numbers of pregnant mice between the EMF-exposed and control group. Our findings indicate that the EMF exposure in preimplantation stage could have detrimental effects on female mouse fertility and embryo development by decreasing the number of blastocysts and increasing the blastocysts DNA fragmentation.

Background:Family of colony-stimulating factors (CSF) have an essential role on early cross talk between embryo and uterine endometrium.Objective:The aim of this study was to evaluate the effects of the single dose of Granulocyte-CSF (G-CSF) injection on clinical outcome of assisted reproductive technology cycle in patients with repeated implantation failures.Materials and Methods:This randomized control trial study was performed on 52 infertile women who referred to the clinic with the history of more than three previous In vitro fertilization/Intracytoplasmic sperm injection-embryo transfer failures. All patients were stimulated with standard long protocol. All embryos were transferred on day five in blastocyst stage in both groups. The treated group received 300 µg (0.5 ml) recombinant human G-CSF subcutaneously which was injected 30 min before blastocyst embryo transfer.Results:There was not statistically significant differences in abortion rate in G-CSF and control group (p=0.09). G-CSF treated group showed higher clinical pregnancy rate in comparison with control group (56.2% vs. 40.0%) but it was not statistically significant (p=0.09). Although live birth rate in G-CSF group was higher than control group (53.1% vs. 35.0%) but there wasn’t statistically significant difference in the overall live birth rate between the two groups (p=0.10). G-CSF group had a twin pregnancies while in control group there was no twin pregnancy.Conclusion:Our result demonstrates the possibility that pregnancy outcome is better in women with repeated unexplained In vitro fertilization failure who are treated with G-CSF.

The study was performed to evaluate the expression of some proapoptotic genes for early prognosis of ovarian cancer. Twenty-four fresh frozen ovarian tumor and 9 normal ones were considered for real-time polymerase chain reaction. CASP8 and BAD genes were decreased in tumoral tissues. Downregulation of CASP8 and BAD genes in ovarian cancer may be an important cause for ovarian cancer. Background: Ovarian cancer as the most lethal gynecologic malignancy in women is poorly detected during early stages of carcinogenesis. Therefore, there is an emergent need to look for specific and sensitive biomarkers for early diagnosis of ovarian cancer. Materials and Methods: In this study, we performed real-time polymerase chain reaction (PCR) to evaluate the expression of six proapoptotic genes, CASP8, BAK, APAF1, BAX, BID, and BAD, which contain CpG islands in their promoter regions. Afterward, the significantly downregulated genes were investigated by HpaII-PCR and methylation-specific PCR (MSP) to determine the methylation status between tumoral and adjacent normal tissues. Results: The real-time PCR results in 24 tumoral and 9 normal adjacent tissues showed decreased expression of CASP8 and BAD genes in tumoral relative to normal samples. Furthermore, the methylation analysis showed no significant methylation between tumoral and normal samples. Conclusion: Taken together, this could be concluded that downregulation of CASP8 and BAD genes in ovarian cancer may be as important causes for ovarian cancer carcinogenesis via inducing resistance to apoptosis; however, the downregulations are not due to promoter hypermethylation.

Noninvasive detection of aberrant DNA methylation could provide invaluable biomarkers for earlier detection of triple‐negative breast cancer (TNBC) which could help clinicians with easier and more efficient treatment options. We evaluated genome‐wide DNA methylation data derived from TNBC and normal breast tissues, peripheral blood of TNBC cases and controls and reference samples of sorted blood and mammary cells. Differentially methylated regions (DMRs) between TNBC and normal breast tissues were stringently selected, verified and externally validated. A machine‐learning algorithm was applied to select the top DMRs, which then were evaluated on plasma‐derived circulating cell‐free DNA (cfDNA) samples of TNBC patients and healthy controls. We identified 23 DMRs accounting for the methylation profile of blood cells and reference mammary cells and then selected six top DMRs for cfDNA analysis. We quantified un‐/methylated copies of these DMRs by droplet digital PCR analysis in a plasma test set from TNBC patients and healthy controls and confirmed our findings obtained on tissues. Differential cfDNA methylation was confirmed in an independent validation set of plasma samples. A methylation score combining signatures of the top three DMRs overlapping with the SPAG6, LINC10606 and TBCD/ZNF750 genes had the best capability to discriminate TNBC patients from controls (AUC = 0.78 in the test set and AUC = 0.74 in validation set). Our findings demonstrate the usefulness of cfDNA‐based methylation signatures as noninvasive liquid biopsy markers for the diagnosis of TNBC.

Triple-negative breast cancer (TNBC) is an aggressive breast cancer subtype associated with a high rate of recurrence and poor prognosis. Recently we identified a hypermethylation in the long noncoding RNA 299 ( LINC00299 ) gene in blood-derived DNA from TNBC patients compared with healthy controls implying that LINC00299 hypermethylation may serve as a circulating biomarker for TNBC. In the present study, we investigated whether LINC00299 methylation is associated with TNBC in a prospective nested breast cancer case–control study within the Generations Study. Methylation at cg06588802 in LINC00299 was measured in 154 TNBC cases and 159 breast cancer-free matched controls using MethyLight droplet digital PCR. To assess the association between methylation level and TNBC risk, logistic regression was used to calculate odd ratios and 95% confidence intervals, adjusted for smoking status. We found no evidence for association between methylation levels and TNBC overall ( P = 0.062). Subgroup analysis according to age at diagnosis and age at blood draw revealed increased methylation levels in TNBC cases compared with controls in the young age groups [age 26–52 ( P = 0.0025) and age 22–46 ( P = 0.001), respectively]. Our results suggest a potential association of LINC00299 hypermethylation with TNBC in young women.

Abstract. Aberrant DNA methylation has been investigated in carcinogenesis and as biomarker for the early detection of colorectal cancer (CRC). The present study aimed to define the methylation status in the regulatory elements of two proapoptotic genes, Fas cell surface death receptor (FAS) and BCL2-associated X protein (BAX). DNA methylation analysis was performed in tumor and adjacent normal tissue using HpaII/MspI restriction digestion and methylation-specific polymerase chain reaction (PCR). The results observed downregulation of the FAS and BAX genes in the CRC tissues compared with the adjacent normal samples. Furthermore, demethylation using 5-aza-2'-deoxycytidine treatment followed by reverse-transcription quantitative PCR were performed on the HT-29 cell line to measure BAX and FAS mRNA expression following demethylation. The 5-aza-2'-deoxycytidine treatment resulted in significant FAS gene upregulation in the HT-29 cell line, but no significant difference in BAX expression. Furthermore, analysis of CpG islands in the FAS gene promoter revealed that the FAS promoter was significantly hypermethylated in 53.3% of tumor tissues compared with adjacent normal samples. Taken together, the results indicate that decreased expression of the FAS gene due to hypermethylation of its promoter may lead to apoptotic resistance, and acts as an important step during colorectal carcinogenesis.

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