Impact of hypoxia and the transcription factors HIF-1α und JMJD1A on the epithelial-mesenchymal transition in head and neck squamous cell carcinoma

The aim of the study was to investigate the impact of hypoxia and the role of the transcription factors HIF-1α (hypoxia inducible factor 1) and JMJD1A (jumonji domain 1A) on epithelial-mesenchymal transition (EMT) in head and neck squamous cell carcinoma (HNSCC). FaDu and Cal33 were incubated for 1-48 h in hypoxia and normoxia. Cell proliferation was quantified by electronic counting, mRNA and protein levels of HIF-1α, JMJD1A, and EMT markers were measured by PCR and western blot. EMT was further explored by immunofluorescence, migration and invasion assays. Cell proliferation was clearly reduced after 48 h in hypoxia for both cell lines. HIF-1α mRNA levels increased after short hypoxia and decreased afterwards, while JMJD1A mRNA levels increased also after prolonged hypoxia. The western blot generated contrary courses for the protein levels. EMT markers varied strongly over the time in both mRNA and protein levels, with the combined results suggesting EMT induction in hypoxia up to 24 h. Immunofluorescence, migration and invasion supported these observations. There are hints for a hypoxia-dependent induction of EMT in HNSCC, while contrary results suggest a more complex interplay of the involved molecular regulators.

Publication History

Article published online:
12 May 2023