Non-coding RNA-Mediated N6-Methyladenosine (m6A) deposition: A pivotal regulator of cancer, impacting key signaling pathways in carcinogenesis and therapy response.

The emergence of RNA modifications has recently been considered as critical post-transcriptional regulations which governed gene expression. N6-methyladenosine (m6A) modification is the most abundant type of RNA modification which is mediated by three distinct classes of proteins called m6A writers, readers, and erasers. Accumulating evidence has been made in understanding the role of m6A modification of non-coding RNAs (ncRNAs) in cancer. Importantly, aberrant expression of ncRNAs and m6A regulators has been elucidated in various cancers. As the key role of ncRNAs in regulation of cancer hallmarks is well accepted now, it could be accepted that m6A modification of ncRNAs could affect cancer progression. The present review intended to discuss the latest knowledge and importance of m6A epigenetic regulation of ncRNAs including mircoRNAs, long non-coding RNAs, and circular RNAs, and their interaction in the context of cancer. Moreover, the current insight into the underlying mechanisms of therapy resistance and also immune response and escape mediated by m6A regulators and ncRNAs are discussed.

Effects of N-Acetylcysteine Supplementation on Oxidative Stress and Expression of Apoptosis-Related Genes in Testicular Tissue of Rats Exposed to Lead.

BACKGROUND: Lead occupational exposure is now a main concern in the modern world. Lead is a non-biodegradable element with multi-devastating effects on different organs. Acute or chronic exposure to lead is reported to be one of the most important causes of infertility both in males and females basically by inducing oxidative stress and apoptosis. OBJECTIVES: The current study scrutinized the mitigating effects of N-acetylcysteine (NAC) on lead toxicity, oxidative stress, and apoptotic/anti-apoptotic genes in the testis tissues of male rats. METHODS: Rats were randomly divided into a control group (G1) and four study groups treated with single and continuous doses of lead with and without NAC administration. Malondialdehyde (MDA), total antioxidant capacity (TAC), and 8-hydroxy-2'-deoxyguanosine (8-OHdG) were analyzed as oxidative stress biomarkers and the expression of apoptosis-related genes was studied using RT-PCR. RESULTS: Continuous exposure to lead caused a significant decrease in sperm count, motility, viability, and morphology (P < 0.001). Number of germinal cells, Leydig cells, spermatocytes, and the diameter of seminiferous tubule were significantly decreased (P < 0.001) in G3 group. Continuous exposure to lead significantly decreased TAC content, but increased the levels of MDA and 8-OHdG (P < 0.001). Administration of continuous dose of lead dramatically increased expression of Bax, Caspase-3, Caspase-8, Cytochrome-C, MMP2, and MMP9 genes in testicular tissue. NAC treatments not only improved morphological changes and sperm quality, but also enhanced antioxidant balance and modulated apoptosis process in testicular tissue of rats. CONCLUSION: Lead exposure strongly motivated testicular cells towards apoptosis, caused an oxidant/antioxidant imbalance, and decreased sperm quality along with morphological changes in testis cells. NAC treatments was associated with protective effects on testicular tissue mainly by rebalancing of the antioxidants capacity, as well as downregulation of apoptosis-related genes.

Antitumor Activities of Green Tea by Up-regulation of miR-181a Expression in LNCaP Cells Using 3D Cell Culture Model.

Background: Prostate Cancer (PCa) is the major reason for the high mortality rates among men worldwide. In fact, current therapeutic approaches are not successful. It appears that discovering more effective methods considering several parameters such as availability, low cost, and no toxicity to normal cells is one of the biggest challenges for interested researchers. Green tea (extracted from the plant Camellia sinensis) with high level of polyphenolic compounds and as the most globally consumed beverage has attracted considerable interest. MicroRNAs (or miRNAs) were considered as novel tools in cancer therapy which modulate various biological events in cell by regulation of gene expression. The aim of the current study was to evaluate the antitumor activity of green tea in LNCaP cells through up-regulation of miR-181a expression. Methods: First, LNCaP cells were cultured and by using quantitative real time PCR (qRT-PCR) and western blot methods, the expression levels of Bax and BCL2 were analyzed. Next, a 3D cell culture model was applied to evaluate the expression of miRNA-181a in LNCaP cells. Results: It was shown that green tea induced cellular apoptosis. The high number of apoptotic nuclei was also shown by using DAPI staining. The inhibition of tumor growth was revealed by analyzing the size and number of spheroids. Also, up-regulation of miR-181a expression in LNCaP cells was revealed after treatment with green tea. Conclusion: Our results are helpful to design antitumor regimens based on consumption of green tea through up-regulation of miRNA-181a expression and induction of apoptosis.

The effect of N-Acetyl cysteine on the expression of Fxr (Nr1h4), LXRα (Nr1h3) and Sirt1 genes, oxidative stress, and apoptosis in the liver of rats exposed to different doses of cadmium.

The aim of this study was to consider the expression of farnesoid X receptor (Fxr), liver X receptor (LXRα) and sirtuin 1 (Sirt1), oxidative stress, inflammation, apoptosis, and the protective role of N-acetylcysteine (NAC) in the liver of rats treated with cadmium (Cd). 30 Wistar rats were divided into 5 groups: G1 (control), G2 (single dose of Cd), G3 (continuous dose of Cd), G4 (single dose of Cd + continuous dose of NAC), and G5 (continuous dose of Cd + continuous dose of NAC). The apoptosis of hepatic cells was measured using the TUNEL assay. Levels of malondialdehyde (MDA), IL-10, TNF-α, and total antioxidant capacity (TAC) were measured by specific kits. The expression of Fxr, LXRα, and Sirt1 genes and ratio of Bax/Bcl2 was considered using RT-PCR. While NAC treatment improved TAC and IL-10 values, it decreased MDA and TNF-α levels in the liver of rats exposed to Cd (P < 0.001). NAC decreased Bax/Bcl2 in the liver of G4 and G5 groups (P < 0.001). Exposure to a continuous dose of Cd decreased Fxr, LXRα, and Sirt1 expression by 36.65- (P < 0.001), 12.52- (P < 0.001) and 11.34-fold (P < 0.001) compared to control, respectively. NAC increased Fxr, LXRα, and Sirt1 expression (P < 0.01) and decreased Cd concentrations in both serum and tissue samples in G4 and G5 groups. Our results suggested that NAC protects liver tissue against Cd toxicity by elevating antioxidant capacity, mitigating oxidative stress, inflammation, apoptosis and up-regulation of FXR, LXR, and SIRT1 genes.

rs1016860 of BCL2 3'UTR associates with hsa-miR-629-5p binding potential in breast cancer and gastric cancer in Isfahan population.

INTRODUCTION: Breast cancer is caused by the interaction of inherited and environmental risk factors. Also, gastric cancer is the second fatal carcinoma. B-cell leukemia/lymphoma 2 gene family plays a crucial role in carcinogenesis by inhibiting the apoptosis process. MATERIALS AND METHODS: In this study, 129 patients with breast cancer and 132 controls as well as 136 patients with gastric cancer and 50 controls were enrolled. We used Real time PCR to determine the genotype of the samples. Finally, we analyzed the diagram based on high temperature melting curve diagram using the MICPCR software, followed by bioinformatics prediction of rs1016860 functions. RESULTS: rs1016860 of BCL2 gene with CC, CT, and TT genotypes were observed in this region. The association of Estrogen receptor and Progesterone receptor, cancer stage and grade of cancer in the patients with genotypes was significant in breast cancer. The association of the status of primary tumor in the patients with genotypes is significant in gastric cancer (Chi-Square p < 0.05 and p = 0.000 did not follow the Hardy-Weinberg equilibrium). DISCUSSION: It was predicted that the TT genotype could be dangerous in breast cancer and gastric cancer; it is expected via bioinformatics that this SNP could lead to signaling pathways of cancer progression, by altering the binding potential of miR-629-5p to BCL2 3'UTR.

Neuroprotective Effect of Pentoxifylline on 3,4-Methylenedioxymethamphetamine-Induced Apoptosis in CA1 Cells of Wistar Rat Hippocampus.

BACKGROUND: 3,4-Methylenedioxymethamphetamine is psychoactive and hallucinogenic and has been shown to produce neurotoxicity both in animals and in humans. Recently, vasodilator drugs such as pentoxifylline (PTX) have been introduced as an alternative with neuroprotective effects. There is no study about the protective effect of PTX on hippocampal apoptosis due to high-dose administration of 3,4-Methylenedioxymethamphetamine (MDMA), so in this study, the protective effect of PTX on the hippocampus of male Wistar rats following high-dose of the drug has been investigated. MATERIALS AND METHODS: Twenty-four male Wistar rats weighing 250-300 g were randomly divided into four groups: control, sham (MDMA injection), experimental (MDMA+PTX injection), and vehicle (MDMA+saline) groups. Two weeks later, the brains were removed and prepared for TUNEL and western blot techniques. Concomitantly the hippocampus was removed to study the change in Bcl-2 and BAX mRNA expression with quantitative real-time polymerase chain reaction. RESULTS: Data showed that the number of apoptotic bodies significantly decreased in the experimental group compared to the other groups, except for in control. Also, further investigation revealed that BAX reduced considerably, while Bcl-2 mRNA expression increased dramatically after PTX treatment. CONCLUSIONS: Our results suggest that PTX may be a neuroprotective agent, and its neuroprotective potential may contribute to reducing the severity of lesions in the hippocampus following a high dose administration of MDMA.

Apoptosis markers of circulating leukocytes are associated with the clinical course of inflammatory bowel disease.

AIM: Here we aimed at evaluating whether the apoptosis status of circulating leukocytes of inflammatory bowel diseases (IBD) patients is attributed to the diseases clinical status. BACKGROUND: Defects in the programmed cell death of inflammatory cells is known as to play a major role in the pathogenesis of IBD, and has been associated with the clinical efficacy of therapeutic agents. METHODS: A total of 50 IBD patients, 25 with remission and 25 with flare-up phase of the disease, who their disease was confirmed by colonoscopy, were included in this cross-sectional study. Pro-apoptotic Bax and anti-apoptotic Bcl-2 mRNA expression, along with Bax/Bcl-2 ratio, as measures of apoptotic status, were assessed in the Peripheral blood mononuclear cell (PBMC) of the patients using semi-quantitative Real-time PCR method. RESULTS: The mean Bax mRNA expression level was 0.54±0.12 in flare-up group and 0.53±0.13 in remission group (p=0.8). The mean Bcl-2 mRNA expression level was 0.63±0.13 in flare-up group and 0.55±0.12 in remission group (p=0.03). The mean Bax/Bcl-2 ratio was 0.88±0.17 in flare-up group and 1±21 in remission group (p=0.05). The mean Bax/Bcl-2 ratio was not statistically significant between different disease types (p=0.54) or therapeutic agents (p=0.7). CONCLUSION: According to our results, alteration in markers of apoptosis could be traced in the circulating leukocytes of IBD patients, which suggest a potential for clinical application of apoptosis markers in disease monitoring and prediction of relapse.

Anticancer Activity of Curcumin on Human Breast Adenocarcinoma: Role of Mcl-1 Gene.

BACKGROUND: Breast cancer is the second leading cause of cancer-related death among females in the world. To date, chemotherapy has been the most frequently used treatment for breast cancer and other cancers. However, some natural products have been used, as alternative treatments for cancers including breast cancer, due to their wide range of biological activities and low toxicity in animal models. OBJECTIVES: The present study examined the anti-proliferative activity of curcumin and its effect(s) on the apoptosis of breast cancer cells. MATERIALS AND METHODS: This study was performed by an in vitro assay and the anticancer effects of curcumin were determined by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide). We used quantitative real time Polymerase Chain Reaction (PCR) for detection of Mcl-1 gene expression in treated groups and then compared them to control samples. RESULTS: In the treatment group, there were higher levels of cell death changes than the control group. The results also showed that the Mcl-1 gene expression declined in the tested group as compared to the control group. CONCLUSIONS: Our present findings indicated that curcumin significantly inhibited the growth of human breast cancer cell MCF-7 by inducing apoptosis in a dose- and time- dependent manner, accompanied by a decrease in MCF-7 cell viability. Furthermore, our results showed that quantitative real-time PCR could be used as a direct method for detection Mcl-1 gene expression in tested samples and normal samples.

The Effect of Pentoxifylline on bcl-2 Gene Expression Changes in Hippocampus after Long-term use of Ecstasy in Wistar Rats.

3,4- Methylenedioxymethamphetamine (MDMA or "Ecstasy") is a psychoactive and hallucinogenic drug of abuse. MDMA has been shown to produce neurotoxicity both in animals and humans. Recently, the vasodilator drugs such as pentoxifylline is one of the new strategies which have been considered as neuroprotector. In this study effect of pentoxifylline on bcl- 2 gene expression changes in hippocampus of rat following long- term use of ecstasy was investigated. 30 male Wistar rats weighing 250-300 g were randomly divided into 5 groups: control (normal), sham (MDMA injection), experimental 1 (MDMA and then PTX injections), experimental 2 (PTX injection and after 1 week, MDMA injection) and vehicle (saline injection) groups. All drugs were injected intraperitoneally.Two weeks later, the hippocampi were removed for studying the changes in bcl-2 gene expression. We used quantitative real time PCR for detection of bcl-2 gene expression in treated groups and then compared them to control samples. The results showed the gene dosage ratio of 0.49, 0.78 and 1.17 for sham, experimental 1 and experimental 2 groups, respectively. The results also showed the bcl-2 gene expression declined in sham group as compared to the experimentalgroups. Furthermore, we observed a significant difference in the bcl-2 gene expression between sham and experimental 2 groups. We conclude that quantitative real time PCR could be used as a direct method for the detection of bcl-2 gene expression in tested and normal samples.