Inhibition of MiR-155 Using Exosomal Delivery of Antagomir Can Up-Regulate PTEN in Triple Negative Breast Cancer.

BACKGROUND: The most aggressive form of breast cancer (BC) is Triple-Negative BC (TNBC), with the poorest prognosis, accounting for nearly 15% of all cases. Since there is no effective treatment, novel strategies, especially targeted therapies, are essential to treat TNBC. Exosomes are nano-sized microvesicles derived from cells and transport various intracellular cargoes, including microRNAs (miRNAs). MiRNAs, small non-coding RNA, are an influential factor in the development of cancerous transformations in cells. METHOD: Bioinformatics analysis of genes related to TNBC revealed that PTEN plays a crucial role in the disease. Relative expression of this gene was analyzed with RT-qPCR in 14 TNBC clinical samples. Electroporation was used to load miRNA antagomir into exosomes extracted from the conditioned medium. Then, the expression of miR-155 and PTEN was evaluated in MDA-MB-231 cells treated with antagomir-loaded exosomes. RESULTS: Based on the bioinformatics analysis, miR-155 is a potent inhibitor of PTEN. Following treatment with antagomir-loaded exosomes, RT-qPCR showed significantly reduced miR- 155 and increased PTEN levels in MDA-MB-231 cells. CONCLUSION: Based on the results of this study, exosomes can be effectively used as a cargo of oligonucleotides like miRNA mimics and antagomirs in targeted therapies.

Effects of Sambucus ebulus Extract on Cell Proliferation and Viability of Triple- Negative Breast Cancer: An In Vitro and In Vivo Study.

BACKGROUND: Triple-negative breast cancer (TNBC) accounts for 15% of all breast cancer (BC) cases and is a severe type of BC. Since medicinal herbs containing biocompatible substances that are accepted by patient more than chemical therapeutics, they can be considered a safe option for treating BC. OBJECTIVE: This study evaluated the effect of Sambucus Ebulus (S. ebulus) extract on a model of TNBC. METHODS: S. ebulus extract was prepared using petroleum ether, ethyl acetate, and methanol. The petroleum ether extract was fractionated and analyzed using vacuum liquid chromatography and GC-MS, respectively. MDAMB- 231 and MCF-10A were used as TNBC and normal breast cells, respectively. Flowcytometry and MTT assays were performed to evaluate cell cycle, apoptosis, and viability of the cells. Gene expression analysis was performed using RT-qPCR. Nude mouse allograft tumor models were used, and pathological sections were evaluated. RESULTS: The findings indicated that S. ebulus extract remarkably decreased cell proliferation and viability. The extract had no toxicity to the normal breast cells but efficiently killed the cancer cells. Cell cycle- and apoptosisrelated gene expression showed that fraction 4 of S. ebulus extract significantly increased the expression of Bax, Bak, P53, and c-MYC. CONCLUSION: This study showed satisfactory results of the effect of S. ebulus extract on clearing BC cells both in vitro and in vivo. Thus, S. ebulus extract may be a safe herbal compound for eliminating BC cells without toxicity to host cells.

Fluid and Electrolyte Disturbances in COVID-19 and Their Complications.

The novel coronavirus disease 2019 (COVID-19) is the cause of an acute respiratory illness which has spread around the world. The virus infects the host by binding to the angiotensin-converting enzyme 2 (ACE2) receptors. Due to the presence of ACE2 receptors in the kidneys and gastrointestinal (GI) tract, kidneys and GI tract damage arising from the virus can be seen in patients and can cause acute conditions such as acute kidney injury (AKI) and digestive problems for the patient. One of the complications of kidneys and GI involvement in COVID-19 is fluid and electrolyte disturbances. The most common ones of these disorders are hyponatremia, hypernatremia, hypokalemia, hypocalcemia, hypochloremia, hypervolemia, and hypovolemia, which if left untreated, cause many problems for patients and even increase mortality. Fluid and electrolyte disturbances are more common in hospitalized and intensive care patients. Children are also at greater risk for fluid and electrolyte disturbances complications. Therefore, clinicians should pay special attention to the fluid and electrolyte status of patients. Changes in fluid and electrolyte levels can be a good indicator of disease progression.

Assessment of AXL and mTOR genes expression in medullary thyroid carcinoma (MTC) cell line in relation with over expression of miR-144 and miR-34a.

OBJECTIVES: The aim of the present study was to investigate the expression of AXL and mTOR genes and their targeting microRNAs (miRNAs) including miR-34a and miR-144 in Medullary Thyroid Carcinoma (MTC) cell line, TT, and determine the effect of these two miRNAs on their target genes to introduce new molecular markers or therapeutics. METHODS: The expression of miR-34a, miR-144, and their targets genes including AXL and mTOR was evaluated by quantitative Real-time PCR. Luciferase assay was performed to confirm the interaction between miRNAs and their target mRNAs. The expression level of AXL and mTOR was evaluated before and after miRNAs induction in TT cell line compared with Cos7 as control cells. RESULTS: The expression of AXL and mTOR were up-regulated significantly, while miR-34a and miR-144 were down-regulated in TT cell line compared to Cos7. After transduction, the overexpression of miR-34a and 144 caused down-regulation of both genes. Luciferase assay results showed that the mTOR is targeted by miR-34a and miR-144 and the intensity of luciferase decreased in the presence of miRNAs. CONCLUSIONS: Based on the results of the present study and since AXL and mTOR genes play a critical role in variety of human cancers, suppression of these genes by their targeting miRNAs, especially miR-34a and miR-144, can be propose as a new strategy for MTC management. However, more studies are needed to approve the hypothesis.

Non-Coding RNAs and Brain Tumors: Insights Into Their Roles in Apoptosis.

A major terrifying ailment afflicting the humans throughout the world is brain tumor, which causes a lot of mortality among pediatric and adult solid tumors. Several major barriers to the treatment and diagnosis of the brain tumors are the specific micro-environmental and cell-intrinsic features of neural tissues. Absence of the nutrients and hypoxia trigger the cells' mortality in the core of the tumors of humans' brains: however, type of the cells' mortality, including apoptosis or necrosis, has been not found obviously. Current studies have emphasized the non-coding RNAs (ncRNAs) since their crucial impacts on carcinogenesis have been discovered. Several investigations suggest the essential contribution of such molecules in the development of brain tumors and the respective roles in apoptosis. Herein, we summarize the apoptosis-related non-coding RNAs in brain tumors.

Circular RNAs: New players in thyroid cancer.

The prevalence of thyroid cancer the most frequent endocrine malignancy, is rapidly increasing. Most of thyroid cancers are relatively indolent, however, some cases still possess a risk of developing into lethal types of thyroid cancer. Regarding its multistep tumorigenesis, the determination of the underlying mechanisms is a vital issue for thyroid cancer therapy. Circular RNAs (circRNAs) are a type of non-coding RNAs with a closed loop structure. Numerous circRNAs have been identified in cancerous tissues. Mounting data recommends that the biological activities of circRNAs, such as serving as microRNA or ceRNAs sponges, interacting with proteins, modulating gene translation and transcription, suggesting that circRNAs will be potential targets as well as agents for the prognosis and diagnosis of diseases, including cancer. Given that circular RNAs acts as oncogenes or tumor suppressors in the thyroid cancer. Several studies documented that circular RNAs via microRNA and protein sponges could regulate a sequences of cellular and molecular mechanisms e.g., apoptosis, angiogenesis, tumor growth, and invasion that are involved in thyroid cancer pathogenesis. Herein, we summarized the role of circular RNAs as therapeutic and diagnostic biomarkers in the thyroid cancer. Moreover, we highlighted the role of these molecules in the pathogenesis of various cancers.

Expression of Bioinformatically Candidate miRNAs including, miR-576-5p, miR-501-3p and miR-3143, Targeting PI3K Pathway in Triple-Negative Breast Cancer.

BACKGROUND: Triple-negative breast cancer (TNBC) is an invasive and lethal form of breast cancer. PI3K pathway, which often activated in TNBC patients, can be a target of miRNAs. The purpose of this study was bioinformatic prediction of miRNAs targeting the key genes of this pathway and evaluation of the expression of them and their targets in TNBC. MATERIALS AND METHODS: We predicted miRNAs targeting PIK3CA and AKT1 genes using bioinformatics tools. Extraction of total RNA, synthesis of cDNA and quantitative real-time polymerase chain reaction were performed from 18 TNBC samples and normal adjacent tissues and cell lines. RESULTS: Our results demonstrated that miR-576-5p, miR-501-3p and miR-3143 were predicted to target PIK3CA, AKT1 and both of these mRNAs, respectively and were down-regulated while their target mRNAs were up-regulated in clinical samples and cell lines. The analysis of the receiver operating characteristic curve was done for the evaluation of the diagnostic value of predicted miRNAs in TNBC patients. CONCLUSION: The findings of our study demonstrated the reverse correlation between miRNAs and their target genes and therefore the possibility of these miRNAs to be proposed as new candidates for TNBC targeted therapies.

Expression of miRNAs Targeting mTOR and S6K1 Genes of mTOR Signaling Pathway Including miR-96, miR-557, and miR-3182 in Triple-Negative Breast Cancer.

Triple-negative breast cancer (TNBC) is a highly aggressive form of breast cancer. Aberrant expression of genes in mTOR pathway and their targeting miRNAs plays an important role in TNBC. The aim of this study was to determine the expression of mTOR and S6K1 and their targeting miRNAs in breast cancer cell lines and clinical samples. miRNAs targeting 3'-UTR of mTOR and S6K1 mRNAs were predicted using bioinformatic algorithms. MDA-MB-231, MCF-7, and MCF-10A as well as 20 TNBC samples were analyzed for gene and miRNA expression using quantitative real-time PCR (RT-qPCR). A receiver operating characteristic (ROC) curve analysis was performed for evaluation of candidate miRNAs as diagnostic biomarkers. miR-96 and miR-557 targeting mTOR and S6K1 mRNAs, respectively, were selected, and miR-3182 was selected as the miRNA targeting both genes. The miRNAs were down-regulated in cell lines, while their target mRNAs were up-regulated. Similar findings were observed in clinical samples. The ROC curve analysis revealed decline in expression of these miRNAs. We suggest that miR-96, miR-557, and miR-3182 can be used as inhibitory agents for mTOR and S6K1 in TNBC-targeted therapy.

Evaluation of miRNAs expression in medullary thyroid carcinoma tissue samples: miR-34a and miR-144 as promising overexpressed markers in MTC.

Medullary thyroid carcinoma (MTC) is a rare neoplasia derived from neural parafollicular C cells. MicroRNAs (miRNAs) are small regulatory RNAs with essential roles in the biology of cancers such as MTC and can be applied as diagnostic markers. According to previous studies, miR-144 and miR-34 and their two oncogenes target, mammalian target of rapamycin (mTOR) and AXL receptor tyrosine kinase (AXL), were selected for further investigations in our study. Thirty MTC samples as well as thirty adjacent normal thyroid tissues were applied in this study including 28 formalin-fixed, paraffin-embedded (FFPE) and 2 fresh-frozen MTC samples. RNA extraction and complementary DNA (cDNA) synthesis were performed for all samples. After primer pairs and probes were designed, real-time polymerase chain reaction (real-time PCR) method was used, and the results were analyzed using 2-ΔΔCt method. Receiver operating characteristic (ROC) curve analysis was applied to assess the diagnostic value of the two miRNAs. AXL protein level was measured in all clinical samples using enzyme-linked immunosorbent assay (ELISA) method. Both miRNAs were up-regulated in all clinical samples compared to the normal tissues. AXL was up-regulated in most clinical samples while mTOR was down-regulated in most samples. Furthermore, the level of AXL protein increased. ROC curve analysis demonstrated that increased expression of miR-34a and miR-144 in MTC patients had significant predictive value. The results demonstrated that high expression of miR-144 and miR-34a can be considered as biomarkers of MTC. However, there was no statistically significant correlation between the expression of these miRNAs and target genes in MTC clinical samples.