Fig. 1. High EPI in patients with breast cancer is accompanied with the increasing expression of USP22.

(A) Representative IHC photomicrographs of tissues stained with USP22 antibodies in patients with breast cancer in clinical breast cancer tissues and para-cancer tissues; Scale bars, 50 μm. (B) Quantification of USP22 expression in breast cancer tissues and para-cancer tissues (n = 65). (C and D) Representative images of USP22 staining in patients with breast cancer (EPI^low, n = 33; EPI^high, n = 32); Scale bars, 50 μm (C). Analysis of USP22 expression in human breast cancer tissues in patients with high and low levels of EPI (D). (E) Relationship between serum EPI levels and USP22 from the IHC staining score in human breast cancer tissues. Pearson correlation coefficient was used as a measure of association. (F to N) Analysis of USP22 protein expression in MDA-MB-231 [(F) to (H)], MCF-7 [(I) to (K)], and SK-BR-3 [(L) to (N)] breast cancer cells treated with indicated concentrations of EPI [(F), (J), and (M)] or time course [(G), (I), and (L)]. Expression of mRNA of USP22 was measured by quantitative RT-PCR [(H), (K), and (N)]; Pearson correlation coefficient was used as a measure of association. Data are expressed as means ± SD of three or more independent experiments. Statistical significance was concluded by unpaired Student’s t test. ****P < 0.0001; ns, no statistical significance.