Clinical Perspectives of Non-Coding RNA in Oral Inflammatory Diseases and Neuropathic Pain: A Narrative Review.

Non-coding RNAs (ncRNAs) represent a research hotspot by playing a key role in epigenetic and transcriptional regulation of diverse biological functions and due to their involvement in different diseases, including oral inflammatory diseases. Based on ncRNAs' suitability for salivary biomarkers and their involvement in neuropathic pain and tissue regeneration signaling pathways, the present narrative review aims to highlight the potential clinical applications of ncRNAs in oral inflammatory diseases, with an emphasis on salivary diagnostics, regenerative dentistry, and precision medicine for neuropathic orofacial pain.

Breast Cancer Response to Therapy: Can microRNAs Lead the Way?

Breast cancer (BC) is a leading cause of death among women with malignant diseases. The selection of adequate therapies for highly invasive and metastatic BCs still represents a major challenge. Novel combinatorial therapeutic approaches are urgently required to enhance the efficiency of BC treatment. Recently, microRNAs (miRNAs) emerged as key regulators of the complex mechanisms that govern BC therapeutic resistance and susceptibility. In the present review we aim to critically examine how miRNAs influence BC response to therapies, or how to use miRNAs as a basis for new therapeutic approaches. We summarized recent findings in this rapidly evolving field, emphasizing the challenges still ahead for the successful implementation of miRNAs into BC treatment while providing insights for future BC management.The goal of this review was to propose miRNAs, that might simultaneously improve the efficacy of all four therapies that are the backbone of current BC management (radio-, chemo-, targeted, and hormone therapy). Among the described miRNAs, miR-21 and miR-16 emerged as the most promising, closely followed by miR-205, miR-451, miR-182, and miRNAs from the let-7 family. miR-21 inhibition might be the best choice for future improvement of invasive BC treatment.New therapeutic strategies of miRNA-based agents alongside current standard treatment modalities could greatly benefit BC patients. This review represents a guideline on how to navigate this elaborate puzzle.

Bone microRNA-21 as surgical stress parameter is associated with third molar postoperative discomfort.

OBJECTIVE: To evaluate an association between bone levels of inflammation/oxidative stress mediators and postoperative discomfort after third molar conventional or piezosurgery. MATERIAL AND METHODS: Twenty-six subjects with bilaterally impacted mandibular third molars, who underwent either piezo or conventional surgery, were included in a split-mouth design study. MicroRNA-21 (miR-21) expression, interleukin-1 beta (IL-1ß), and vascular endothelial growth factor (VEGF) proteins, as well as superoxide dismutase (SOD) activity in alveolar bone, were evaluated. Pain intensity, the first pain appearance, analgesic first use and total dose taken, trismus, and swelling were clinically recorded. RESULTS: MiR-21 expression was higher while VEGF protein was lower in piezosurgery vs. conventional groups. The differences in IL-1ß protein and SOD activity were not significant between groups. The pain intensity on the first day was significantly decreased in piezosurgery group. The first pain appearance and the first analgesic taken were reported sooner in conventional vs. piezosurgical group. Significantly pronounced trismus on the third day following conventional surgery was found. In conventional group, significantly increased trismus was observed on the third compared to the first postoperative day. MiR-21 showed significant correlation with the first pain appearance. CONCLUSION: Delayed onset of less pronounced postoperative pain after piezosurgical vs. conventional extraction of impacted lower third molar was significantly associated with expression of bone miR-21. CLINICAL RELEVANCE: Alveolar bone miR-21 may reflect surgical stress and is associated with third molar postoperative pain onset.

Discovery of the Biginelli hybrids as novel caspase-9 activators in apoptotic machines: Lipophilicity, molecular docking study, influence on angiogenesis gene and miR-21 expression levels.

In order to investigate potential therapeutically agents, novel products of Biginelli reaction (4a-l) were synthesized and exposed to cytotoxic and caspase activities, angiogenesis, cell cycle distribution, gene and microRNA expression levels, lipophilicity assessment and docking study. Among the twelve novel compounds (4a-l) evaluated for the cytotoxic activity, five of them (4c, 4d, 4f, 4k and 4l) that showed excellent activity on the tested cell lines (HeLa, LS174 and A549) were selected for further evaluation. Interestingly, compound 4f has up to three times higher selectivity index (SI) towards cancer cells than cisplatin (on HeLa, LS174 and A549 SI = 18.2, 13.5 and 11.2, respectively). The obtained results from cell cycle distribution and caspase activity indicate that tested compounds (4c, 4d, 4f, 4k and 4l) promoted caspase-9 activation, implicated in the intrinsic pathway of apoptosis. Lipophilicity of 4a-l was determinate by using reversed-phase high-performance liquid chromatography.

Highly selective anthraquinone-chalcone hybrids as potential antileukemia agents.

A series of 23 novel anthraquinone-chalcone hybrids containing amide function was synthesized and structurally characterized. Sixteen compounds exerted strong cytotoxic activities against K562, Jurkat and HL-60 leukemia cell lines and significantly lower cytotoxic effects against normal MRC-5 cells, indicating very high selectivity in their anticancer action. The compounds 6g, 6u and 6v activate apoptosis in K562 cells through the extrinsic and intrinsic apoptotic pathway. The compound 6e triggered apoptosis in K562 cells only through the extrinsic apoptotic pathway. Treatment of K562 cells with each of these four compounds caused decrease in the expression levels of MMP2, MMP9, and VEGF, suggesting their anti-invasive, antimetastatic and antiangiogenic properties. The compounds 6g and 6v downregulated expression levels of miR-155 in K562 cells, while compounds 6e and 6u upregulated miR-155 levels in treated cells, in comparison with control cells. The structure-based 3-D QSAR models for 6f, 6e, 6i and 6l describe pro-apoptotic activity against caspase-3.

MicroRNA-146a and microRNA-155 as novel crevicular fluid biomarkers for periodontitis in non-diabetic and type 2 diabetic patients.

AIM: Recent studies point at the crucial role of epigenetic mechanisms in the development of multifactorial diseases such as periodontitis and diabetes mellitus (DM) type 2. In addition, circulatory microRNAs (miRs) have emerged as novel biomarkers for various diseases. Aim of this study was to investigate the levels of miR-146a and miR-155 and superoxide dismutase (SOD) activity in gingival crevicular fluid (GCF) of periodontitis patients with (CPDM) and without (CP) DM type 2 as well as in periodontally healthy, control groups (PHDM and PH, respectively). MATERIAL AND METHODS: miR modulation was analysed using quantitative real-time PCR while SOD activity was measured spectrophotometrically. RESULTS: The upregulation of miR-146a and miR-155 was observed in CP and CPDM patients' baseline, while the levels decreased after 6 weeks of the non-surgical therapy to the levels comparable to PH and PHDM, respectively. Expression levels of miRs positively correlated with SOD activity. Levels of miR-146a were higher in PHDM compared to PH patients. Multivariate analysis revealed that levels of miR-146a and miR-155 were significantly associated with periodontitis when adjusting for age and gender. CONCLUSIONS: miR-146a and miR-155 may be considered as possible novel biomarkers for periodontitis in non-diabetic and type 2 diabetic patients.

Estradiol-mediated regulation of hepatic iNOS in obese rats: Impact of Src, ERK1/2, AMPKα, and miR-221.

PURPOSE: This study aimed to investigate in vivo effects of estradiol on the regulation of hepatic inducible nitric oxide synthase (iNOS) expression in the high fat (HF) diet-induced obesity. Also, we aimed to investigate whether activation of the extracellular signal-regulated kinase (ERK1/2), adenosine monophosphate-activated protein kinase (AMPK), Src kinase, and miR-221 is involved in estradiol-mediated regulation of iNOS in the liver of obese male Wistar rats. Male Wistar rats were fed a standard laboratory diet or a HF diet for 10 weeks. Half of HF rats were treated with estradiol intraperitoneally (40 µg/kg), whereas the other half were placebo-treated 24 H before euthanasia. Results show that estradiol treatment of HF rats decreased hepatic iNOS mRNA (P < 0.05) and protein expression (P < 0.01), the protein levels of p65 subunit of nuclear factor κB (P < 0.05) and ERα (P < 0.05), ERK1/2 phosphorylation (P < 0.001), and ERα/Src kinase association (P < 0.05). By contrast, hepatic Src protein level (P < 0.05), AMPKα phosphorylation (P < 0.05), and miR-221 expression (P < 0.05) were increased in HF rats after estradiol treatment. Our results indicate that estradiol in vivo regulates hepatic iNOS expression in obese rats via molecular mechanisms involving ERK1/2, AMPK, Src, and miR-221 signaling.

The influence of host factors and sequence variability of the p7 region on the response to pegylated interferon/ribavirin therapy for chronic hepatitis C genotype 1b in patients from Serbia.

The goal of this study was to identify host and viral factors affecting the response to pegylated interferon/ribavirin (PEG-IFN/RBV) treatment in patients with chronic hepatitis C genotype 1b. Baseline characteristics of the patients and sequences within the p7 region were analyzed in pre-treatment serum samples from 53 individuals with chronic hepatitis C genotype 1b and related to the outcome of therapy. We found a significant correlation between age and response to therapy (p < 0.001). Furthermore, the pre-treatment viral load was closely associated with the stage of liver fibrosis (p < 0.001). The presence of fewer than 4 mutations and age above 40 were significantly associated with non-response (NR) (p < 0.001). Our findings may be useful for estimating the likelihood of achieving a sustained virologic response (SVR) in patients who are chronically infected with hepatitis C virus genotype 1b.

Identification of a Novel hsa_circ_0058058/miR-324-5p Axis and Prognostic/Predictive Molecules for Acute Myeloid Leukemia Outcome by Bioinformatics-Based Analysis.

Acute myeloid leukemia (LAML) is one of the most prevalent hematological malignancies. In recent years, while targeted approaches have shown promise in the fight against cancer, the treatability and prognosis of patients remain inadequate due to the shortage of drugs. Noncoding RNAs, especially circular RNA (circRNA) and microRNA (miRNA), have been shown to play a unique role in tumor development. This study aims to identify the disease-associated circRNA-miRNA-mRNA network by bioinformatic analysis and investigate the mechanisms in the development and progression of LAML. Additionally, it reveals the promising roles of these molecules as a diagnostic biomarker and therapeutic target for LAML treatment. Using various bioinformatics approaches, we identified the hsa_circ_0058058/miR-324-5p axis in LAML and its possible functions in LAML development. According to our results, hsa circ-0058058 can regulate the expression of AP1G1 and SP1 through miR-324-5p to support angiogenesis, the cell cycle, and DNA replication processes. Downregulation of hsa circ-0058058 may contribute to the anticancer functions of miR-324-5p on LAML tumorigenesis, and upregulation of miR-324-5p can abolish the oncogenic effects of AP1G1 and SP1 on LAML tumorigenesis. Additionally, highly enriched pathways indicated possible interactions between molecules underlying LAML pathology. Targeted molecules within this network may be able to function as therapeutic and diagnostic biomarkers for disease, while more research and clinical confirmation are needed.

Comparative analysis of chemical profiles, antioxidant, antibacterial, and anticancer effects of essential oils of two Thymus species from Montenegro.

The essential oils of Thymus vulgaris (TVEO) and Thymus serpyllum (TSEO) show different biological activities. The aim of the study was to evaluate the biological activities of TVEO and TSEO from Montenegro. The main components of TVEO were p-cymene (29.52%), thymol (22.8%) and linalool (4.73%) while the main components of TSEO were p-cymene (19.04%), geraniol (11,09%), linalool (9.16%), geranyl acetate (6.49%) and borneol (5.24%). Antioxidant activity determined via DPPH for TVEO was 4.49 and FRAP 1130.27, while for TSEO it was estimated that DPPH was 4.88 µL/mL and FRAP was 701.25 µmol FRAP/L. Both essential oils were active against all tested bacteria, with the highest level of sensitivity of E. coli with MIC of 1.5625 µL/mL. Essential oils showed strong cytotoxic effects on human cancer cell lines, with IC50 values ranging from 0.20 to 0.24 µL/mL for TVEO and from 0.32 to 0.49 µL/mL for TSEO. TVEO caused apoptosis in cervical adenocarcinoma HeLa cells through activation of caspase-3 and caspase-8, while TSEO caused apoptosis through caspase-3. EOs decreased levels of oxidative stress in normal MRC-5 cells. HeLa cells treated with TVEO had reduced MMP2 expression levels, while cells treated with TSEO had lowered MMP2 and MMP9 levels. The treatment of HeLa cells with TVEO increased the levels of miR-16 and miR-34a, indicating potential tumor-suppressive properties. Our findings suggest that Thymus essential oils may be considered as good candidates for further investigation as cancer-chemopreventive and cancer-therapeutic agents.

Synergy of experimental and computational chemistry: structure and biological activity of Zn(II) hydrazone complexes.

In this paper, three different Zn(II) complexes with (E)-2-(2-(1-(6-bromopyridin-2-yl)ethylidene)hydrazinyl)-N,N,N-trimethyl-2-oxoethan-1-aminium chloride (HLCl) have been synthesized and characterized by single crystal X-ray diffraction, elemental analysis, IR and NMR spectroscopy. All complexes are mononuclear, with the ligand (L) coordinated in a deprotonated formally neutral zwitterionic form via NNO donor set atoms. Complex 1 forms an octahedral geometry with the composition [ZnL2](BF4)2, while complexes 2 [ZnL(NCO)2] and 3 [ZnL(N3)2] form penta-coordinated geometry. Density functional theory (DFT) calculations were performed to enhance our understanding of the structures of the synthesized complexes and the cytotoxic activity of the complexes was tested against five human cancer cell lines (HeLa, A549, MDA-MB-231, K562, LS 174T) and normal human fibroblasts MRC-5. Additionally, antibacterial and antifungal activity of these complexes was tested against a panel of Gram-negative and Gram-positive bacteria, two fungal strains, and a yeast strain. It is noteworthy that all three complexes show selective antifungal activity comparable to that of amphotericin B. Molecular docking analysis predicted that geranylgeranyl pyrophosphate synthase, an enzyme essential for sterol biosynthesis, is the most likely target for inhibition by the tested complexes.

Key roles of C2/GAP domains in SYNGAP1-related pathophysiology.

Mutations in SYNGAP1 are a common genetic cause of intellectual disability (ID) and a risk factor for autism. SYNGAP1 encodes a synaptic GTPase-activating protein (GAP) that has both signaling and scaffolding roles. Most pathogenic variants of SYNGAP1 are predicted to result in haploinsufficiency. However, some affected individuals carry missense mutations in its calcium/lipid binding (C2) and GAP domains, suggesting that many clinical features result from loss of functions carried out by these domains. To test this hypothesis, we targeted the exons encoding the C2 and GAP domains of SYNGAP. Rats heterozygous for this deletion exhibit reduced exploration and fear extinction, altered social investigation, and spontaneous seizures-key phenotypes shared with Syngap heterozygous null rats. Together, these findings indicate that the reduction of SYNGAP C2/GAP domain function is a main feature of SYNGAP haploinsufficiency. This rat model provides an important system for the study of ID, autism, and epilepsy.

Clinically informative microRNAs for SARS-CoV-2 infection.

COVID-19 is a viral respiratory infection induced by the newly discovered coronavirus SARS-CoV-2. miRNA is an example of a strong and direct regulator of a gene's transcriptional activity. The interaction between miRNAs and their target molecules is responsible for homeostasis. Virus-derived and host-derived miRNAs are involved in the activity of hiding from immune system cells, inducing the inflammatory reaction through interplay with associated genes, during SARS-COV-2 infection. Interest in miRNAs has raised the comprehension of the machinery and pathophysiology of SARS-COV-2 infection. In this review, the effects and biological roles of miRNAs on SARS-CoV-2 pathogenicity and life cycle are described. The therapeutic potential of miRNAs against SARS-CoV-2 infection are also mentioned.

MicroRNA networks linked with BRCA1/2, PTEN, and common genes for Alzheimer's disease and breast cancer share highly enriched pathways that may unravel targets for the AD/BC comorbidity treatment.

MicroRNAs (miRNAs) are involved in the regulation of various cellular processes including pathological conditions. MiRNA networks have been extensively researched in age-related degenerative diseases, such as cancer, Alzheimer's disease (AD), and heart failure. Thus, miRNA has been studied from different approaches, in vivo, in vitro, and in silico including miRNA networks. Networks linking diverse biomedical entities unveil information not readily observable by other means. This work focuses on biological networks related to Breast cancer susceptibility 1 (BRCA1) in AD and breast cancer (BC). Using various bioinformatics approaches, we identified subnetworks common to AD and BC that suggest they are linked. According to our results, miR-107 was identified as a potentially good candidate for both AD and BC treatment (targeting BRCA1/2 and PTEN in both diseases), accompanied by miR-146a and miR-17. The analysis also confirmed the involvement of the miR-17-92 cluster, and miR-124-3p, and highlighted the importance of poorly researched miRNAs such as mir-6785 mir-6127, mir-6870, or miR-8485. After filtering the in silico analysis results, we found 49 miRNA molecules that modulate the expression of at least five genes common to both BC and AD. Those 49 miRNAs regulate the expression of 122 genes in AD and 93 genes in BC, from which 26 genes are common genes for AD and BC involved in neuron differentiation and genesis, cell differentiation and migration, regulation of cell cycle, and cancer development. Additionally, the highly enriched pathway was associated with diabetic complications, pointing out possible interplay among molecules underlying BC, AD, and diabetes pathology.

Melatonin Action in Type 2 Diabetic Parotid Gland and Dental Pulp: In Vitro and Bioinformatic Findings.

Type 2 diabetes mellitus (T2DM) is associated with functional deterioration of the salivary gland and dental pulp, related to oxidative stress. The aim was to integrate experimental and bioinformatic findings to analyze the cellular mechanism of melatonin (MEL) action in the human parotid gland and dental pulp in diabetes. Human parotid gland tissue was obtained from 16 non-diabetic and 16 diabetic participants, as well as human dental pulp from 15 non-diabetic and 15 diabetic participants. In human non-diabetic and diabetic parotid gland cells (hPGCs) as well as in dental pulp cells (hDPCs), cultured in hyper- and normoglycemic conditions, glial cell line-derived neurotrophic factor (GDNF), MEL, inducible nitric oxide synthase (iNOS) protein expression, and superoxide dismutase (SOD) activity were measured by enzyme-linked immunosorbent assay (ELISA) and spectrophotometrically. Bioinformatic analysis was performed using ShinyGO (v.0.75) application. Diabetic participants had increased GDNF and decreased MEL in parotid (p < 0.01) and dental pulp (p < 0.05) tissues, associated with increased iNOS and SOD activity. Normoglycemic hDPCs and non-diabetic hPGCs treated with 0.1 mM MEL had increased GDNF (p < 0.05), while hyperglycemic hDPCs treated with 1 mM MEL showed a decrease in up-regulated GDNF (p < 0.05). Enrichment analyses showed interference with stress and ATF/CREB signaling. MEL induced the stress-protective mechanism in hyperglycemic hDPCs and diabetic hPGCs, suggesting MEL could be beneficial for diabetes-associated disturbances in oral tissues.

MicroRNAs in Prostate Cancer Following Radiotherapy: Towards Predicting Response to Radiation Treatment.

Prostate cancer (PCa) is the second most frequently diagnosed male cancer worldwide. Early diagnosis of PCa, response to therapy, and prognosis still represent a challenge. Nearly 60% of PCa patients undergo radiation therapy (RT) which might cause side effects. Despite numerous researches in this field, predictive biomarkers for radiation toxicity are still not elucidated. MicroRNAs as posttranscriptional regulators of gene expression are shown to be changed during and after irradiation. MicroRNA level changes might be utilized to predict response to RT in the near future, which might help clinicians to make the decision on treatment regimens if needed. Individual radiation response results from the interactions among radiation treatment parameters and the biological background of each patient. In this review, we have listed and described miRNAs involved in response to RT in PCa and highlighted potential candidates for future biological tests predicting radiation response to RT, with the special focus on side effects of RT. According to described literature, we concluded that let-7, miR-21, miR-34a, miR-146a, miR-155, and members of miR-17/92 cluster might be promising candidates for biological tests predicting radiosensitivity of PCa patients undergoing radiation treatment. Predictive miRNA panels, especially for acute and late side effects of RT, can serve as a starting point for decisions for individualized RT planning. We believe that this review might be one step closer to understanding molecular mechanisms underlying individual radiation response of patients with PCa.

circRNAs in drug resistance of breast cancer.

Breast cancer (BC) is the most common heterogeneous disease in women and one of the leading causes of cancer-related death. Surgery, chemotherapy, radiotherapy, hormone, and targeted therapy are the gold standards for BC treatment. One of the significant challenges during the treatment of BC represents resistance to chemotherapeutics, resistance that severely limits the use and effectiveness of the drugs used for BC treatment. Therefore, it is essential to develop new strategies to improve therapeutic efficacy. Circular RNAs (circRNAs) are a large group of non-coding RNAs that covalently form closed circular loops by joining their 5', and 3'; ends. Accumulating evidence suggests that circRNAs have a vital role in cancer development, progression, and BC resistance to chemotherapy. The purpose of this review is to discuss the biological properties of circRNAs, and how circRNAs induce resistance to conventional therapeutic anti-cancer drugs used in BC treatment, by emphasizing and summarizing the potential roles of circRNAs in mechanisms of drug resistance, such as drug efflux, apoptosis dysfunction, autophagy, and DNA damage repair. CircRNAs are associated with drug resistance via ATP-binding cassette (ABC) efflux transporters, while some others by inhibition of cell apoptosis, thus leading to resistance to tamoxifen in BC cells. In contrast, others are involved in the promotion of BC cells chemoresistance by doxorubicin-induced autophagy. CircRNAs may have clinical significance in regulating or overcoming BC drug resistance and may give directions towards a novel approach to personalized BC treatment. CircRNAs may significantly contribute to the identification of new therapeutic targets for the prevention of BC chemoresistance.

Association between microRNAs 10b/21/34a and acute toxicity in glioblastoma patients treated with radiotherapy and temozolomide.

A personalized approach to chemoradiation is important in reducing its potential side effects and identifying a group of patients prone to toxicity. MicroRNAs have been shown to have a predictive potential for radiotoxicity. The goal of the study was to test if levels of miRNA in peripheral blood mononuclear cells of glioblastoma patients are associated with toxicity and to identify the peak time point for toxicity. MicroRNA-10b/21/34a levels were measured in 43 patients with and without toxicity, at baseline, at the 15th, and at the 30th fraction by Real-Time quantitative Polymerase Chain Reaction. MicroRNA-10b/21 levels increased with toxicity grade (p = 0.014; p = 0.013); miR-21/34a levels were significantly different between patients with and without toxicity at the 15th fraction (p = 0.030; p = 0.045), while miR-34a levels significantly changed during treatment (p < 0.001). All three miRNAs showed a significantly high positive correlation with one another. MiR-34a might be considered as a predictive factor for toxicity due to its changes during treatment, and differences between the groups with and without toxicity; miR-10b might be used to predict toxicity; miR-10b/21 might be used for predicting the grade of toxicity in GB patients.

Dual function miR-205 is positively associated with ER and negatively with five-year survival in breast cancer patients.

BACKGROUND: Precise molecular characterization of breast cancer, especially triple negative (TNBC) as the most lethal subtype, is needed to stratify patients for the individual treatment approach. MicroRNA-205 (miR-205) has tumor-suppressive and oncogenic functions across different cancers. Therefore, miR-205 might have a different role in TNBC and estrogen receptor (ER) positive BC. Our aim was to investigate how miR-205 expression is associated with ER/progesteron receptor status, clinical parameters, pathohistological characteristics of BC, and survival of patients METHODS: We determined miR-205 relative expressions in 73 primary breast tumors (50 TNBC and 23 ER+) by quantitative Real-time polymerase chain reaction (qPCR) and compared it to clinicopathological characteristics and outcome. RESULTS: The highest levels of miR-205 were in the ER+ /PR+ group, and the lowest in the TNBC group (p = 0.009). Significantly higher levels of miR-205 were also observed in the ER+ compared with the ER-negative group, regardless of the PR status (p = 0.002). Low miR-205 expression level was associated with prognostic stage III in TNBC samples (p = 0.049). Patients who received adjuvant chemotherapy had significantly lower levels of miR-205 (p = 0.016). Patients who received hormone therapy had significantly higher levels of miR-205 (p = 0.007). The low-miR-205 patients had significantly higher 5-year survival rates (p = 0.041). CONCLUSION: The expression of miR-205 in BC is subtype-specific and high expression is associated with the ER+ tumors. The miR-205 expression might be a useful marker of TNBC progression. High miR-205 expression had a detrimental effect on BC patient outcome. Our results indicate that miR-205 might be utilized in clinical practice as a biomarker and an adjunct parameter for the selection of the most effective therapeutic modality.