Long non-coding RNAs PVT1, CCAT2, and TCF7L2, and miR-33 and c-Myc expression in oral squamous cell carcinoma and oral lichen planus patients.

OBJECTIVE

The objective of this study was to assess the potential of TCF7L2, CCAT2, and PVT1 LncRNAs, c-Myc, and miR-33 as biomarkers for early diagnosis and differentiation of oral squamous cell carcinoma (OSCC) and premalignant lesions.

DESIGN

Bioinformatics tools, including COSMIC, GeneMANIA, PathVisio, KEGG Pathway Database, IntOGen, and WikiPathways, were used to investigate the signaling pathways of cancer-associated genes. The limma package was utilized for statistical analysis to identify Differentially Expressed Genes (DEGs) between OSCC tumor and normal samples. The regulatory microRNAs were analyzed using miRDB, miRWalk, and TargetScan. The type of cancer for analysis was selected using IntOGen. The expression levels of LncRNAs, miR-33, and c-Myc were measured by polymerase chain reaction (PCR) in 28 OLP and 30 OSCC tissue samples, compared to 30 healthy and 30 OSCC-adjacent tissue specimens as control groups. Data were analyzed using the Mann-Whitney test, receiver operating characteristic (ROC) curve, and multiple linear regression.

RESULTS

The expression of c-Myc (3.53 ± 2.78 vs 0.93 ± 0.50), PVT1 (10.94 ± 8.49 vs 0.91 ± 0.48), CCAT2 (11.77 ± 10.00 vs 0.92 ± 0.95), and TCF7L2 (6.48 ± 4.30 vs 1.27 ± 0.96) was significantly higher in OSCC samples compared to OLP (P < 0.001). Conversely, miR-33 expression was significantly lower in OSCC samples (0.24 ± 0.25 vs 4.90 ± 3.90). There was a significant correlation between c-Myc, CCAT2, PVT1, and miR-33 expression and clinicopathological characteristics of OSCC specimens. In OSCC samples, c-Myc, PVT1, CCAT2, and TCF7L2 showed a significant positive correlation with each other, while miR-33 expression was negatively correlated with the overexpression of other genes. The area under the curve (AUC) for c-Myc, PVT-1, CCAT2, miR-33, and TCF7L2 were 0.917, 1.000, 0.979, 0.006, and 0.929, respectively.

CONCLUSIONS

Our findings suggest that c-Myc and LncRNAs (TCF7L2, PVT1, and CCAT2) are upregulated and miR-33 is downregulated in OSCC compared to OLP samples. These genes may serve as potential genetic biomarkers for diagnosis and prediction of clinicopathological features of OSCC.