Circulating miR-31 as an effective biomarker for detection and prognosis of human cancer: a meta-analysis

Exploring the Potential of Non-Coding RNAs as Liquid Biopsy Biomarkers for Lung Cancer Screening: A Literature Review

Lung cancer represent the leading cause of cancer mortality, so several efforts have been focused on the development of a screening program. To address the issue of high overdiagnosis and false positive rates associated to LDCT-based screening, there is a need for new diagnostic biomarkers, with liquid biopsy ncRNAs detection emerging as a promising approach. In this scenario, this work provides an updated summary of the literature evidence about the role of non-coding RNAs in lung cancer screening. A literature search on PubMed was performed including studies which investigated liquid biopsy non-coding RNAs biomarker lung cancer patients and a control cohort. Micro RNAs were the most widely studied biomarkers in this setting but some preliminary evidence was found also for other non-coding RNAs, suggesting that a multi-biomarker based liquid biopsy approach could enhance their efficacy in the screening context. However, further studies are needed in order to optimize detection techniques as well as diagnostic accuracy before introducing novel biomarkers in the early diagnosis setting.

The meta-signature guided investigation of miRNA candidates as potential biomarkers of oral cancer

OBJECTIVES

This study aimed to experimentally validate dysregulated expression of miRNA candidates selected through updated meta-analysis of most commonly deregulated miRNAs in oral cancer and to explore their diagnostic and prognostic potential.

MATERIALS AND METHODS

Five miRNAs (miR-31-3p, miR-135b-5p, miR-18a-5p, miR-30a-5p, miR-139-5p) from updated meta-signature were selected for validation by qRT-PCR method in 35 oral cancer clinical specimens and adjacent non-cancerous tissue.

RESULTS

Updated meta-analysis has identified 13 most commonly deregulated miRNAs in oral cancer. Seven miRNAs were consistently up-regulated (miR-21-5p, miR-31-3p, miR-135b-5p, miR-31-5p, miR-424-5p, miR-18a-5p, miR-21-3p), while five were down-regulated (miR-139-5p, miR-30a-3p, miR-375-3p, miR-376c-3p, miR-30a-5p). Increased expression of miR-31-3p, miR-135b-5p, as well as decreased expression of miR-139-5p and miR-30a-5p were confirmed in oral cancer compared to adjacent non-cancerous tissue. A three-miRNAs combination (miR-31-3p, miR-139-5p, miR-30a-5p) gave the most promising diagnostic potential for discriminating oral cancer from non-cancerous tissue (AUC: 0.780 (95% CI: 0.673-0.886), p<0.0005, sensitivity 94.3%, specificity 51.4%). High expression of miR-135b-5p, miR-18a-5p and miR-30a-5p was associated with poor survival (p=0.003, p=0.048, p=0.016, respectively).

CONCLUSION

miR-31-3p, miR-139-5p, miR-30a-5p panel was confirmed as a potential diagnostic biomarker when distinguishing oral cancer from non-cancerous tissue. miR-135b-5p, miR-18a-5p and miR-30a-5p might serve as potential biomarkers of poor survival of oral cancer patients.

Renal Oncocytoma: The Diagnostic Challenge to Unmask the Double of Renal Cancer

Renal oncocytoma represents the most common type of benign neoplasm that is an increasing concern for urologists, oncologists, and nephrologists due to its difficult differential diagnosis and frequent overtreatment. It displays a variable neoplastic parenchymal and stromal architecture, and the defining cellular element is a large polygonal, granular, eosinophilic, mitochondria-rich cell known as an oncocyte. The real challenge in the oncocytoma treatment algorithm is related to the misdiagnosis due to its resemblance, at an initial radiological assessment, to malignant renal cancers with a completely different prognosis and medical treatment. Unfortunately, percutaneous renal biopsy is not frequently performed due to the possible side effects related to the procedure. Therefore, the majority of oncocytoma are diagnosed after the surgical operation via partial or radical nephrectomy. For this reason, new reliable strategies to solve this issue are needed. In our review, we will discuss the clinical implications of renal oncocytoma in daily clinical practice with a particular focus on the medical diagnosis and treatment and on the potential of novel promising molecular biomarkers such as circulating microRNAs to distinguish between a benign and a malignant lesion.

Association between miRNA signatures in serum samples from epidermal growth factor inhibitor treated patients and skin toxicity

Objective: Epidermal growth factor receptor inhibitors (EGFRI) are used as targeted cancer therapy. On average 70% of patients treated with EGFRIs suffer from skin toxicity. Studies showed a correlation between overall survival and the appearance of a skin rash, which is used as a biomarker for therapy efficacy. Micro RNAs (miRNA) as tumor or resistance biomarkers for cancer therapy are also highly investigated. In our study, we searched for associations of miRNA expression profiles in serum, with the severity of skin rash, in order to identify tentative therapy predictive biomarkers.

Materials and Methods: Five candidate miRNAs were selected, based on an earlier in vitro next-generation-sequencing-experiment and after literature search. MiR-21, miR-31, miR-17, miR-106b and miR-520e were investigated in serum samples from patients (n = 254) treated with EGFRI. The quantitative expression of miRNA was tested for association with the occurrence/severity of the rash.

Results: In our cohort of patients treated with EGFR inhibiting monoclonal antibodies, miR-21 and miR-520e serum concentrations were negatively correlated with severity of skin rash (p-value 0.000582 and 1.53e-07 linear-trend-test) whereas for miR-31, a positive correlation was observed (p-value 9.01e-06 linear-trend-test).

Conclusions: This suggests that miR-21, miR-31 and miR-520e expression might be a treatment dependent marker for EGFRI induced skin rash.

Smartphone DNA or RNA Sensing Using Semisynthetic Luciferase-Based Logic Device

Detection of specific oligonucleotide sequences is central to numerous applications, and technologies amenable to point-of-care diagnostics or end users are needed. Here, we report a technology making use of a bioluminescent readout and smartphone quantification. The sensor is a semisynthetic luciferase (H-Luc-PNA conjugate) that is turned on by a strand-displacement reaction. We demonstrated sensing of three different microRNAs (miRs), as representative cancer biomarkers, and demonstrate the possibility to integrate an AND gate to sense two sequences simultaneously.

A Hypothesis of Circulating MicroRNAs' Implication in High Incidence of Atrial Fibrillation and Other Electrocardiographic Abnormalities in Cancer Patients

MicroRNAs are short non-coding RNA molecules that control posttranscriptional gene expression and are present in tissues cells but also circulate in biological fluids in various forms (exosome, connected with proteins, apoptotic bodies, etc.). The roles that circulated extracellular serum microRNAs possess in cancer development, like in the delivery from a recipient cell to distant tissues and the repression of host genes resulting in the impairment of critical functions, are still undetermined. Disturbances, such as the higher incidence of atrial fibrillation in cancer patients, could be analyzed in the frame of suppressive action of circulated microRNAs in genes that control cardiac conduction in atrium. More precisely, mir-21 overexpression in tissues promotes atrium fibrosis and impairs conductibility. A possible hypothesis is that the high levels of circulating microRNA in cancer may exert the same effect. Further experiments are necessary to corroborate the hypothesis.

miR-31-5p Is a Potential Circulating Biomarker and Therapeutic Target for Oral Cancer

MicroRNAs have been proposed as novel biomarkers for the diagnosis and treatment of many types of cancer. The levels of five candidate microRNAs (miRNAs) (miR-99a-5p, miR-31-5p, miR-138-5p, miR-21-5p, and miR-375-3p) in sera from oral cancer patients and paired tumor and normal tissues were detected by real-time qPCR. The diagnostic power of these miRNAs was analyzed by receiver operating characteristic (ROC) curves. Patient-derived xenograft (PDX) models of oral cancer were established and utilized to verify the potential therapeutic effect of miR-31-5p. Candidate miRNAs were screened from our previous studies and verified in 11 paired oral cancer and adjacent normal tissues. Only serum miR-31-5p levels were significantly different between oral cancer patients and healthy controls and between pre- and postoperative patients. Based on the logistic regression model, this panel of five miRNAs distinguished oral cancer patients from healthy control, with an area under the ROC curve (AUC) of 0.776 (sensitivity = 76.8% and specificity = 73.6%). Furthermore, a miR-31-5p mimic enhanced the proliferation of normal epithelial cells, and antagomiR-31-5p inhibited the proliferation of oral cancer cells in vitro. In vivo, antagomiR-31-5p significantly inhibited tumor growth in oral cancer PDX models. Our findings suggest that circulating miR-31-5p might act as an independent biomarker for oral cancer diagnosis and could serve as a therapeutic target for oral cancer.

MicroRNAs as Urinary Biomarker for Oncocytoma

The identification of benign renal oncocytoma, its differentiation from malignant renal tumors, and their eosinophilic variants are a continuous challenge, influencing preoperative planning and being an unnecessary stress factor for patients. Regressive changes enhance the diagnostic dilemma, making evaluations by frozen sections or by immunohistology (on biopsies) unreliable. MicroRNAs (miRs) have been proposed as novel biomarkers to differentiate renal tumor subtypes. However, their value as a diagnostic biomarker of oncocytoma in urines based on mechanisms known in oncocytomas has not been exploited. We used urines from patients with renal tumors (oncocytoma, renal cell carcinoma: clear cell, papillary, chromophobe) and with other urogenital lesions. miRs were extracted and detected via qRT-PCR, the respective tumors analyzed by immunohistology. We found isocitrate dehydrogenase 2 upregulated in oncocytoma and oncocytic chromophobe carcinoma, indicating an increased Krebs cycle metabolism. Since we had shown that all renal tumors are stimulated by endothelin-1, we analyzed miRs preidentified by microarray after endothelin-1 stimulation of renal epithelial cells. Four miRs are proposed as presurgical urinary biomarkers due to their known regulatory mechanism in oncocytoma: miR-498 (formation of the oncocytoma-specific slice-form of vimentin, Vim3), miR-183 (associated with increased CO₂ levels), miR-205, and miR-31 (signaling through downregulation of PKC epsilon, shown previously).

Blood Serum From Head and Neck Squamous Cell Carcinoma Patients Induces Altered MicroRNA and Target Gene Expression Profile in Treated Cells

The head and neck squamous cell carcinoma (HNSCC) represents one of the most common cancers in humans. Close to 600,000 new diagnoses are made every year worldwide and over half of diagnosed patients will not survive. In view of this low survival rate, the development of novel cell-based assays for HNSCC will allow more mechanistic approaches for specific diagnostics for each individual patient. The cell-based assays will provide more informative data predicting cellular processes in treated patient, which in effect would improve patient follow up. More importantly, it will increase the specificity and effectiveness of therapeutic approaches. In this study, we investigated the role of serum from HNSCC patients on the regulation of microRNA (miRNA) expression in exposed cells in vitro. Next-generation sequencing of miRNA revealed that serum from HNSCC patients induced a different miRNA expression profile than the serum from healthy individuals. Out of 377 miRNA detected, we found that 16 miRNAs were differentially expressed when comparing cells exposed to serum from HNSCC or healthy individuals. The analysis of gene ontologies and pathway analysis revealed that these miRNA target genes were involved in biological cancer-related processes, including cell cycle and apoptosis. The real-time PCR analysis revealed that serum from HNSCC patients downregulate the expression level of five genes involved in carcinogenesis and two of these genes-P53 and SLC2A1-are direct targets of detected miRNAs. These novel findings provide new insight into how cancer-associated factors in circulation regulate the expression of genes and regulatory elements in distal cells in favor of tumorigenesis. This has the potential for new therapeutic approaches and more specific diagnostics with tumor-specific cell lines or single-cell in vitro assays for personalized treatment and early detection of primary tumors or metastasis.