Mediator complex subunit 19 (Med19) is a critical subunit of the mediator complex that forms a bridge between the transcription factors and RNA polymerase II. Although it has been reported that Med19 plays an important role in stabilizing the whole mediator complex, its biological importance in tongue cancer cell proliferation and migration has not been addressed.

By using MTT, BrdU incorporation, colony formation, flow cytometric, tumorigenesis and transwell assays, We tested the Med19 role on tongue cancer cell growth and migration.

We demonstrated that lentivirus-mediated Med19 knockdown could arrest tongue cancer cells at G1 phase, inhibit tongue cancer cell proliferation and migration in vitro. The tumorigenicity of Med19 short hairpin RNA (shRNA)-expressing lentivirus infected tongue cancer cells were decreased after inoculating into nude mice.

These results indicate that Med19 plays an important role in tongue cancer proliferation and migration, and suggest possible applications for tongue cancer therapy.