Estrogen receptors regulate galectin‑3 in androgen‑independent DU‑145 prostate cancer cells

The aim of the present study was to investigate the role of estrogen receptor (ER)α and ERβ, and galectin‑3 (GAL‑3) in migration and invasion of androgen‑independent DU‑145 prostate cancer cells, and to examine the regulation of the expression of GAL‑3 by the activation of these receptors. Wound healing and cell invasion assays were performed using the control (basal level of cellular function) and treated DU‑145 cells. At 24 h of treatment, 17β‑estradiol (E2), the ERα‑selective agonist, 4,4',4"‑(4‑propyl‑(1H)‑pyrazole‑1,3,5‑triyl)trisphenol (PPT), or the ERβ‑selective agonist, 2,3‑bis(4‑hydroxyphenyl)‑propionitrile (diarylprepionitrile; DPN), increased the migration and invasion of the DU‑145 cells. Pre‑treatment with the ERα‑ and ERβ‑selective antagonists blocked these effects, indicating that ERα and ERβ are upstream receptors regulating these processes. Western blot analysis and immunofluorescence staining for the detection of the GAL‑3 were performed using the control and treated DU‑145 cells. Treatment of the DU‑145 cells with E2, PPT or DPN for 24 h increased the expression of the GAL‑3 compared to the control. Furthermore, a specific inhibitor of GAL‑3 (VA03) inhibited the migration and invasion of DU‑145 cells, indicating the involvement of the complex ERα/GAL‑3 and ERβ/GAL‑3 in the regulation of these processes. On the whole, the present study demonstrates that the activation of both ERs increases the expression and signaling of GAL‑3, and promotes the migration and invasion of DU‑145 cells. The findings of the present study provide novel insight into the signatures and molecular mechanisms of ERα and ERβ in DU‑145 cells.