001; Fig. 1A). Additionally, in female adjacent tissues, BMS-777607 in vivo PTPRO was expressed much more highly, compared to male samples (P < 0.01).

PTPRO expression levels in male HCC tissues were negative in 37 cases and weak in 83 cases, according to IHC staining analysis, whereas 18 cases were negative and 42 weak in female HCC tissue samples. We also found greater levels in female adjacent tissues and lower levels in male adjacent tissues (Fig. 1E). Statistical analysis of integrated optical density (IOD) values of 180 slides stained with PTPRO is shown in the histogram (Fig. 1C; P < 0.01). Additionally, our findings indicated that PTPRO expression level was associated with tumor multiplicity and tumor size in the 180 HCC patients (P < 0.01). However, PTPRO expression levels appeared to have only a slight association with age and Edmondson's stage (Supporting Table 1). Taken together, these findings suggest that the decreased expression of PTPRO was associated with the generation or progression of HCC; moreover, our findings suggest that click here PTPRO expression level is potentially mediated by estrogen

regulation. Based on the gender disparity of PTPRO expression and the previous findings in breast cancer, we hypothesized that the decreased PTPRO level in HCC could be the result of ERs. As suggested by our recent report, ERα was distinctly down-regulated in male HCC cases, and this finding correlated with its defensive potential against the development of HCC.39 In this study, we identified the gender difference in ERα expression in 180 pairs of HCC specimens Aldol condensation using real-time PCR (Fig. 1B) and IHC analysis (Fig. 1E; P < 0.001). We randomly analyzed correlations between PTPRO and ERα expression in 180 HCC specimens and found that they were positively correlated in adjacent tissues (Fig. 1F; r2 = 0.342, P < 0.001). Additionally,

we investigated ERβ levels, but found no significant differences between HCC and adjacent tissues. Thus, of the two types of ERs, our findings demonstrated that ERα was principally correlated with PTPRO expression in HCC. To confirm the pathological deficiency and gender bias of PTPRO expression, we collected liver specimens from diethylnitrosamine (DEN) treated and healthy mice and detected the expression of ERα and PTPRO by immunochemical staining. Gender disparity of ERα and PTPRO expression was evident in healthy C57BL/6 mice (Fig. 2). Subsequently, in mouse HCC, we found a significant decrease in ERα and PTPRO levels in male mice (P < 0.001), in contrast to the constant expression levels found in female mice that failed in HCC generation. To examine the potential relationship between ERα and PTPRO expression levels, we utilized lentivirus to derive ERα-overexpressing HCC cell lines Huh-7-ERα and SMCC-7721-ERα and determined the fluctuations of PTPRO levels. Expression level of PTPRO was elevated by ERα in the presence of E2 (Fig. 3A). Moreover, we verified by real-time PCR that PTPRO mRNA was up-regulated (Fig. 3B; P < 0.