The over and lower expression of CASC9 and lncRNA 00277 were respectively negative to sensitivity to gefitinib in PC9G2 cells, and taken together, it was reported that they contributed to NSCLC cells EGFR-TKI resistance through interacting with their co-expressed gene, namely PcGs, and affected different biological pathways [87] (Figure 1). The gene discussed is EGFR; the disease is non-small cell lung carcinoma.