Fig. 1

hsa_circ_0055538 is downregulated in OSCC tissue specimens and cell lines. a, b qRT-PCR was used to determine the hsa_circ_0055538 expression level in a tumor tissue specimens from patients with OSCC, relative to that in adjacent normal tissues (n = 44); and b HOK, CAL27, SCC9, SCC15, and SCC25 cell lines. c, d The hsa_circ_0055538 expression level in stable SCC9 (c) and CAL27 (d) cell lines was quantified by qRT-PCR. GFP expression was examined under a fluorescence microscope using stable SCC9 and CAL27 cell lines. BF bright field. e, f qRT-PCR quantification of hsa_circ_0055538 levels in SCC9 (e) and CAL27 (f) cells transfected with hsa_circ_0055538 siRNA. Si and NC refer to OSCC cells transfected with hsa_circ_0055538 siRNA or normal controls. Data are presented as mean ± SEM of three independent experiments. Student’s t test, ***P < 0.001