Curcumin Sensitizes 4T1 Murine Breast Cancer Cells to Cisplatin Through PAR4 Secretion.

BACKGROUND/AIM: Prostate apoptosis response 4 (PAR4), a tumour-suppressor protein, selectively induces apoptosis of cancer cells without affecting normal cells. Its soluble form is induced by secretagogues (e.g., chloroquine), and it induces apoptosis by interacting with the receptor of glucose-regulated protein 78, which is overexpressed in cancer cells. In this study, curcumin was analyzed as an inducer of PAR4 expression in 4T1 murine breast cancer cell. and its ability to induce PAR4 secretion in Balb/c mice. In addition, the cisplatin sensitizing effect of soluble PAR4 was analyzed. MATERIAL AND METHODS: The 4T1 cell line was treated in vitro using different concentrations of curcumin; cell viability was analyzed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and PAR4 expression by western blotting. The expression of soluble PAR4 in the serum of mice treated with intraperitoneal curcumin was analyzed using the dot-blot method. Moreover, MTT assay was used to analyze the effects of serum from curcumin-treated mice on cell viability. Tumor size was analyzed in mice treated with curcumin alone and in combination with cisplatin. RESULTS: Curcumin showed a dose- and time-dependent effects on cell viability on 4T1 cells, as well as increasing PAR4 expression. Compared with the control group (phosphate-buffered saline), mice treated with curcumin showed an increase in plasma PAR4. In the Balb/C tumor model, mice treated with curcumin and cisplatin showed greater tumor shrinkage than the control group. CONCLUSION: These results indicate that curcumin induces expression of soluble PAR4 and sensitizes tumor cells to cisplatin.

The Inflammatory Process Modulates the Expression and Localization of WT1 in Podocytes Leading to Kidney Damage.

BACKGROUND/AIM: Wilms' tumor 1 (WT1) is involved in the development of the urogenital system and is expressed in podocytes throughout life. Inflammation of renal glomeruli causes renal damage-induced nephrotic syndrome and steroid-resistant nephrotic syndrome have mutations in the WT1 gene. The aim of this work was to determine if the inflammatory process modulates the expression and localization of WT1 in podocytes that cause kidney damage using lipopolysaccharide (LPS)-treated mice as a sepsis model. MATERIALS AND METHODS: In investigation of renal damage, proteinuria and histology were analyzed. WT1 modulation was analyzed by indirect immunofluorescence, immunohistochemistry and western blot assays, and proinflammatory cytokines were analyzed by quantitative polymerase chain reaction assay. RESULTS: WT1 expression decreased most at 24 and 36 h after the induction of inflammation and phosphorylated WT1 was mainly localized in the cytoplasm, reduced nephrin mRNA expression and increased mRNA expression of tumor necrosis factor α and interleukin 1ß. CONCLUSION: These results indicate that the immune system plays an important role in the modulation of WT1, leading to kidney damage.