Lymph node or perineural invasion is associated with low miR-15a, miR-34c and miR-199b levels in head and neck squamous cell carcinoma.

Background: MicroRNAs (miRNAs or miRs) are post-transcriptional regulators of eukaryotic cells and knowledge of differences in miR levels may provide new approaches to diagnosis and therapy.

Methods: The present study measured the levels of nine miRs in head and neck squamous cell carcinomas (HNSCC) and determined whether clinical pathological features are associated with differences in miR levels. SET (I2PP2A) and PTEN protein levels were also measured, since their levels can be regulated by miR-199b and miR-21, respectively.

PI3K-PTEN dysregulation leads to mTOR-driven upregulation of the core clock gene BMAL1 in normal and malignant epithelial cells.

Dysfunctional clock signaling is observed in a variety of pathological conditions. Many members of the clock gene family are upregulated in tumor cells. Here, we explored the consequences of a commonly disrupted signaling pathway in head and neck cancer on the regulation of circadian clock genes.