The effects of GABA and GABA agents on NSCLC cell. H1299 cell proliferation was suppressed by GABA in a dose-dependent manner measured by MTT assays (Figure 1A and C). The inhibitory effects of GABA (100 μM/L) on H1299 cell growth were time-dependent (Figure 1B and D). This inhibitory effects of GABA (100 μM/L) on H1299 cell growth was blocked by CGP co-cultured but not by PTX (Figure 1E and F). Proliferation index was calculated as the ratio of the absorbance of cells incubated with GABA or GABA agents compare with negative controls (NC) which was defined as the cells cultured only with complete medium. N =3. *P < 0.05, ** P < 0.01, *** P < 0.001 vs NC.