PDE10A and squamous cell lung carcinoma: Having established that the compounds 1–5 appear to have dual activity in CHO-KI cells where the A2AR was over expressed we then extended our studies to a series of lung carcinoma cells: two lung squamous cell carcinomas (LUSC): LK-2 and H520, and two lung adenocarcinoma cells (LUAC): H1563 and H1792, which express differing levels of the four adenosine receptor subtypes and PDE10A (Fig. 7a).