In this study, using real-time reverse transcriptase-PCR, we analyzed the expression of apoptosis-regulating miRNAs (miR-15a, miR-16, miR-17-5p, miR-20a, miR-21, miR-29a, and miR-34a) in 20 oral squamous cell carcinoma and 5 normal oral mucosa tissue samples.
Expression of miR-27a, showing up-regulation in CIN2-3 compared to CIN1 (p=0.028) and miR-34a (down-regulated), correlated with HPV 16 positivity (CIN2-3/CIN1: p=0.027 and SCC/CIN2-3: p=0.036).
In this study, we examined primary oral SCCs for the expression of 6 candidate miRNAs, of which five (miR-34a, miR-143, miR-373, miR-380-5p, and miR- 504) regulate the tumor suppressor TP53 and one (miR-99a) is involved in AKT/mTOR signaling.
Significant overexpression of miR-21 (p=0.004), miR-27a (p=0.02), miR-34a (p<0.001), miR-196a (p=0.027) and miR-221 (p=0.031) was characteristic of HPV-positive squamous cell carcinomas in contrast to adenocarcinomas of the same HPV status.
Here we report that microRNA-34a (miR-34a) functions as a novel node in the squamous cell differentiation network, with SIRT6 as a critical target. miR-34a expression increases with keratinocyte differentiation, while it is suppressed in skin and oral SCCs, SCC cell lines, and aberrantly differentiating primary human keratinocytes (HKCs).
Two microRNA panels yielded high diagnostic accuracy in discriminating SCLC from NSCLC (miR-29a and miR-375; area under the curve [AUC], 0.991 and 0.982 for training and validation data set, respectively) and in differentiating SQ from AC (miR-205 and miR-34a; AUC, 0.977 and 0.982 for training and validation data set, respectively) in FFPE surgical lung specimens.
These results strongly suggest that miR-34a expression can be an independent prognostic biomarker in patients with sinonasal squamous cell carcinoma who are undergoing treatment with cis-diamminedichloroplatinum.