In addition, Piao et al. conducted a very interesting experiment in which they cocultured GC cells in conditioned medium from GC cells grown under hypoxia or normoxia and found that lncRNA PCGEM1 was highly expressed in GC cells cultured under hypoxic conditions and induced the invasion and metastasis of GC cells under normoxic conditions. Here, PCGEM1 is linked to gastric cancer.