miRNAs expression of oral squamous cell carcinoma patients: Validation of two putative biomarkers

Abstract

microRNA expression patterns have provided new directions in the search of biomarkers with prognostic value and even in the search of novel therapeutic targets for several neoplasms. Specifically, miRNAs profiling in oral squamous cell carcinoma (OSCC) represents a web of intrigue in the study of oral carcinogenesis. The objective of the present study was twofold:The first study phase comprised case-control groups: A) 8 OSCC-affected patients and 8 healthy controls. Microarray technology (Affymetrix miRNA Array Plate 4.1) was used for miRNAs expression profile. Deregulated miRNAs were studied using Diana Tools miRPath 3.0 to associate miRNA targets with molecular pathways via Kyoto Encyclopedia of Genes and Genomes (KEGG). In a second phase, 2 miRNAs chosen for the subsequent RT-qPCR validation were studied in a second OSSC cohort (n = 8).Microarray analysis identified 80 deregulated miRNAs (35 over-expressed and 45 under-expressed). Two miRNAs (miR-497-5p and miR-4417) were chosen for further validation via RT-qPCR. Prognostic analysis did not ascertain relevant relation between miR-497-5p or miR-4417 expression and clinical or pathological parameters, except high miR-4417 in the case of nodular affectation (P = .035) and diminished miR-497-5p radiotherapy-treated patients (P = .05). KEGG analysis revealed that deregulated miRNAs were implicated in several biological pathways such as Proteoglycans in cancer.Our data suggest an altered miRNAs profiling in OSCC-affected patients. We have verified the altered expression of miR-497-5p and miR-4417 in OSCC samples and related the deregulated miRNAs with the 'proteoglycans in cancer' pathway. Further longitudinal studies with large samples are warranted to confirm the present findings.

Figure 1

Volcano Plot. Deregulated miRNA in microarray analysis. The amount of microRNAs with statistically significant differences of expression can be appreciated in this graph. Those with a significantly higher expression are yellow highlighted and with a significantly lower expression green highlighted. Fold change is specified on the x-axis.

Figure 2

Molecular pathways in which deregulated miRNAs may be involved. Diana Tools results.

Figure 3

Hyaluronan (HA) proteoglycans molecular pathway and miRNAs deregulated in our study. Proteins target by one miRNA are coloured in yellow, and those targets by more than 1 miRNA are coloured in orange.

Figure 4

Chondroitin sulfate /Dermatan Sulfate (CSPG/DSPG) and Keratan Sulfate (KSPG) proteoglycans molecular pathway and miRNAs deregulated in our study. Proteins target by 1 miRNA are coloured in yellow, and those targets by more than 1 miRNA are coloured in orange.

Figure 5

Heparan sulfate (HSPGs) Proteoglycans molecular pathway and miRNAs deregulated in our study. Proteins target by 1 miRNA are coloured in yellow, and those targets by more than 1 miRNA are coloured in orange.