Plasma and saliva miR-21 expression in colorectal cancer patients

Abstract

MicroRNA-21 (miR-21) expression was quantified by real-time qRT-PCR in peripheral blood and saliva samples obtained from patients diagnosed with colorectal cancer (CRC) of varying degrees of malignancy and healthy volunteers. All patients had adenocarcinoma located in the distal colon at different stages. Significant differences were detected between the control group and the total experimental group of CRC patients (plasma, P = 0.0001; saliva, P = 5e-12). MiR-21 expression was also significantly different in certain subgroups of patients with CRC disease stages II-IV as compared to the control group. No correlation of miR-21 expression was found with regard to gender and age of patents. Also, there were no significant individual correlations and linear regression of miR-21 expression in the plasma and saliva. The estimated diagnostic sensitivity and specificity of miR-21 expression were respectively 65 and 85% in the plasma, and 97 and 91% in the saliva. Our data suggest that miR-21 in both the saliva and plasma could be a proper biomarker for CRC screening, although the saliva miR-21 expression test looks preferable due to its higher sensitivity, specificity, and technical simplicity.

A Novel Saliva-Based miRNA Signature for Colorectal Cancer Diagnosis

“…Although few studies have characterized the miRNA expression profile in saliva from different cancer locations, no other study performed wide profiling of salivary miRNAs in CRC patients to date. Actually, the unique study that evaluated saliva as a source of potential biomarkers for diagnostic purposes in CRC was developed by Sazanov et al [14] These authors found significantly increased salivary expression levels of miR-21 in CRC compared to healthy controls. This miRNA was detected in all cases of CRC included in our discovery phase, showing higher mean expression levels in patients than controls but no significant differences, probably because of the lower number of samples analyzed in our discovery phase.…”

“…Aberrant expression profiles of salivary miRNAs have been detected in different types of cancer, showing their power as a discriminatory clinical method [13]. Unlike other tumors, only salivary miR-21 was analyzed in CRC by Sazanov et al [14], finding miR-21 expression significantly higher in the saliva of CRC patients compared to healthy controls.…”

Cell-Free microRNAs as Potential Oral Cancer Biomarkers: From Diagnosis to Therapy

“…It is important to highlight that some previously mentioned salivary miRNAs have also been described as dysregulated in other malignancies and inflammatory diseases. In this sense, salivary miR-21 was significantly upregulated in remote tumors (colorectal [89], oesophageal [90,91], and pancreatic [92]) and chronic inflammation (ulcerative colitis [93] and oral lichen planus [94]). Other salivary miRNAs, such as miR-31, miR-125a, and miR-27b were significantly altered in oral potentially malignant disorders [94,95].…”

Prognostic Biomarkers of Gastrointestinal Neoplasia

“…Уровни экспрессии miR-21 в плазме и слюне у больных КРР в 4 раза выше (p = 0,0001 и 10 -12 соответственно), чем у здоровых лиц. Анализ слюны на miR-21 является идеальной неинвазивной процедурой с более высокой чувствительностью (97 %) и специфичностью (91 %), чем анализ плазмы (65 и 85 % соответственно) [40].…”