Non-coding RNAs as Key Regulators of the Notch Signaling Pathway in Glioblastoma: Diagnostic, Prognostic, and Therapeutic Targets

Glioblastoma multiforme (GBM) is a highly invasive brain malignancy originating from astrocytes, accounting for approximately 30% of central nervous system malignancies. Despite advancements in therapeutic strategies including surgery, chemotherapy, and radiopharmaceutical drugs, the prognosis for GBM patients remains dismal. The aggressive nature of GBM necessitates the identification of molecular targets and the exploration of effective treatments to inhibit its proliferation. The Notch signaling pathway, which plays a critical role in cellular homeostasis, becomes deregulated in GBM, leading to increased expression of pathway target genes such as MYC, Hes1, and Hey1, thereby promoting cellular proliferation and differentiation. Recent research has highlighted the regulatory role of non-coding RNAs (ncRNAs) in modulating Notch signaling by targeting critical mRNA expression at the post-transcriptional or transcriptional levels. Specifically, various types of ncRNAs, including long non-coding RNAs (lncRNAs) and microRNAs (miRNAs), have been shown to control multiple target genes and significantly contribute to the carcinogenesis of GBM. Furthermore, these ncRNAs hold promise as prognostic and predictive markers for GBM. This review aims to summarize the latest studies investigating the regulatory effects of ncRNAs on the Notch signaling pathway in GBM.

MiRNAs: Emerging Agents for Therapeutic Effects of Polyphenols on Ovarian Cancer

In terms of female reproductive tract cancers, ovarian cancer remains the principal reason for mortality globally and is notably difficult to identify in its early stages. This fact highlights the critical need to establish prevention strategies for patients with ovarian cancer, look for new robust diagnostic and prognostic markers, and identify potential targets of response to treatment. MicroRNAs (miRNAs) are one of the novel treatment targets in cancer treatment. Thus, understanding the part of miRNAs in the pathogenesis and metastasis of ovarian cancer is at the center of researchers' attention. MiRNAs are suggested to play a role in modulating many essential cancer processes, like cell proliferation, apoptosis, differentiation, adhesion, epithelial-mesenchymal transition (EMT), and invasion. In two recent decades, natural polyphenols' anti-cancer features have been a focal point of research. Meanwhile, polyphenols are good research subjects for developing new cancer treatments. Polyphenols can modify miRNA expression and impact the function of transcription factors when used as dietary supplements. Multiple works have indicated the impact of polyphenols, including quercetin, genistein, curcumin, and resveratrol, on miRNA expression in vitro and in vivo. Here, we provide an in-depth description of four polyphenols used as dietary supplements: quercetin, genistein, curcumin, and resveratrol, and we summarize what is currently known about their regulatory abilities on influencing the miRNA functions in ovarian tumors to achieve therapeutic approaches.

Aptamers and New Bioreceptors for the Electrochemical Detection of Biomarkers Expressed in Hepatocellular Carcinoma

Hepatocellular carcinoma is a malignancy associated with high mortality and increasing incidence. Early detection of this disease could help increase survival and overall patient benefit. Non-invasive strategies for the diagnosis of this medical condition are of utmost importance. In this scope, the detection of hepatocellular carcinoma biomarkers could provide a useful diagnostic tool. Aptamers represent as short, single-stranded DNAs or RNAs that can specifically bind selected analytes, and also as pseudo-biorecognition elements that can be employed for electrode functionalization. Also, other types of DNA sequences can be used for the construction of DNA-based biosensors applied for the quantification of hepatocellular carcinoma biomarkers. Herein, we will be analyzing recent examples of aptasensors and DNA biosensors for the detection of hepatocellular carcinoma biomarkers like micro-RNAs, long non-coding RNAs, exosomes, circulating tumor cells and proteins. The literature data is discussed comparatively in a critical manner highlighting the advantages of using electrochemical biosensors in diagnosis, as well as the use of nanomaterials and biocomponents in the functionalization of electrodes for improved sensitivity and selectivity.

An Overview of Targeting Legumain for Inhibiting Cancers

Legumain (LGMN; EC: 3.4.22.34), an asparaginyl endopeptidase (AEP) or asparaginyl carboxypeptidase (ACP), is a member of the C13 family of cysteine proteases. Elevated expression of LGMN is reported not only in the tumor cells of breast, prostate, and liver but also in the macrophages of the tumor microenvironment. Hence, LGMN is considered as a key protein involved in the regulation of tumor angiogenesis, invasion, and metastasis. Targeting LGMN using siRNA or pharmacological agents and peptides was reported to reduce cancer cell proliferation in vitro and shrink tumor size in vivo. Moreover, expression of LGMN is significantly low in normal cells compared to tumor cells or tumor-associated macrophages (TAMs); hence, legumain can be used as a marker for tumor recognition and targeting. Therefore, approaches inhibiting LGMN expression or activity are more viable, less toxic, and help in developing the targeted therapeutics. However, to date, LGMN targeting strategies have not been well reported. In this review, an attempt was made to summarize articles pertaining to LGMN (a) structure and activity; (b) oncogenic nature; (c) pharmacological inhibitors; and (d) targeting approaches that inhibit tumor growth. Furthermore, a list of existing gaps in LGMN research is highlighted, which needs additional studies.

Salivary mir-27b Expression in Oral Lichen Planus Patients: A Series of Cases and a Narrative Review of Literature

BACKGROUND

microRNAs play a critical role in auto-immunity, cell proliferation, differentiation and cell death. miRNAs are present in all biological fluids, and their expression is essential in maintaining regular immune functions and preventing autoimmunity, whereas miRNA dysregulation may be associated with the pathogenesis of autoimmune and inflammatory diseases. Oral lichen planus (OLP) is an inflammatory disease mediated by cytotoxic T cells attack against epithelial cells. The present study aims to perform a specific microRNA expression profile through the analysis of saliva in this disease.

METHODS

The study group was formed by five patients (mean age 62.8±1.98 years; 3 females/2 males) affected by oral lichen planus and control group by five healthy subjects (mean age 59.8 years±2.3; 3 females/ 2 males); using a low-density microarray analysis, we recorded a total of 98 differentially expressed miRNAs in the saliva of patients with oral lichen planus compared to the control group. The validation was performed for miR-27b with qRT-PCR in all saliva samples of oral lichen planus group.

RESULTS

89 miRNAs were up-regulated and nine down-regulated. In details, levels of miR-21, miR- 125b, miR-203 and miR15b were increased (p<0.001) in study group while levels of miR-27b were about 3.0-fold decreased compared to controls (p<0.001) of miR-27b expression in OLP saliva. QRTPCR validation confirmed the down regulation of miR-27b in all saliva samples.

CONCLUSION

Collecting saliva samples is a non-invasive procedure and is well accepted by all patients. microRNAs can be readily isolated and identified and can represent useful biomarkers of OLP.

MiR-340 Inhibits Triple-Negative Breast Cancer Progression by Reversing EZH2 Mediated miRNAs Dysregulated Expressions

The anti-tumor efficacy of miR-340 has been recently characterized in cancers. However, the underlying mechanisms of miR-340 inhibited cell growth and invasion in triple-negative breast cancer (TNBC) have not been well elucidated. In this study, we found that miR-340 expression was negatively correlated with EZH2 (Enhancer of zeste homolog 2) expression in TNBC tissues and cell lines. Subsequent luciferase reporter assay confirmed that EZH2 was a novel molecule target of miR-340. Upregulated miR-340 levels by mimics transfection significantly inhibited the MDA-MB-231 and MDA-MB-468 breast cancer cells proliferation, invasion and migration, and induced more cell apoptosis. Meanwhile, miR-340 inhibited the tumor growth in an orthotopic MDA-MB-231 breast cancer mouse model. Furthermore, we found the reduced EZH2 expression by miR-340 mimics transfection decreased the DNMT1, H3K27me3, β-catenin and P-STAT3 expressions, which ultimately resulted in miR-21 activity blockage and miR-200a/b expression upregulation. The results of rescue experiments further confirmed that miR-340 inhibited triple-negative breast cancer progression through targeting EZH2. Taken together, our results identified miR-340 as a tumor suppressor in TNBC, moreover, an EZH2 medicated regulatory loop was established. Post-transcriptional suppression of EZH2 expression not only blocked STAT3 mediated miR-21 trans-activation, but also reversed the miR-200a/b silencing via reducing DNMT1 and H3K27me3 expressions. MiR-21 inhibition and miR-200a/b expression triggered by miR-340 ultimately cooperated in the TNBC progression.

miR-15b and miR-21 as Circulating Biomarkers for Diagnosis of Glioma

Malignant gliomas are lethal primary intracranial tumors. To date, little information on the role of deregulated genes in gliomas have been identified. As the involvement of miRNAs in the carcinogenesis is well known, we carried out a pilot study to identify, as potential biomarkers, differentially expressed microRNAs in blood samples of patients affected by glioma. We studied the miRNAs' expression, by means of microarray and Real-Time PCR, in 30 blood samples from glioma patients and in 82 blood samples of patients suffering from: (a) various neurological disorders (n=30), (b) primary B-lymphoma of the Central Nervous System (PCNSL, n=36) and (c) secondary brain metastases (n=16). By quantitative real time reverse-transcriptase polymerase chain reaction (qRT-PCR), we identified significantly increased levels of two candidate biomarkers, miR-15b and miR-21, in blood of patients affected by gliomas. ROC analysis of miR-15b biomarker levels allowed to differentiate patients with tumour from patients without glioma. Furthermore, combined expression analyses of miR15b and miR-21 distinguished between patients with and without glioma (90% sensitivity and 100% specificity). In addition, a decrement in the expression levels of miR-16 characterized glioblastomas compared to low grade and anaplastic gliomas. In conclusion, this pilot study suggest that it's possible to identify the disease state by meaning miR-15b and miR-21 markers in blood, while miR-16 can be used to distinguish glioblastoma from other grade gliomas. They can potentially be used as biomarkers for non-invasive diagnosis of gliomas; further studies are mandatory to confirm our preliminary findings.