Fig. 1

Serine starvation inhibits proliferation and induces G1 phase cell cycle arrest in ESCC cells. A Proliferation curves of ESCC cells grown in Com, -Ser, -Gly or -SG medium. B The growth of ESCC cells cultured in indicated concentration of serine was determined by using MTT assay. C The mortality of ESCC cells treated in Com or -Ser medium for 24 h was detected by using trypan blue staining. D Cell cycle distribution in ESCC cells. The ESCC cells were synchronized and arrested in G0/G1 phase by a double-thymidine block, then simultaneously released in media with or without serine for indicated time, followed by flow cytometry. E Representative immunofluorescence images (left) and quantification (right) of EdU incorporation assay in ESCC cells cultured in Com or -Ser medium for 24 h. DAPI was used to stain nucleus. Scale bar represents 100 μm. Data are presented as mean ± SD. Two-way ANOVA with Tukey’s post hoc test (A) and unpaired two-sided Student’s t test (C and E). ns: no significance, *p < 0.05, **p < 0.01, ***p < 0.001