Talcum powder induces malignant transformation in normal human primary ovarian epithelial cells.

BACKGROUND

Several studies have linked perineal use of talcum powder to increased risk of ovarian cancer (OC). Here, we determined that exposure to talcum powder induces malignant transformation in human normal ovarian cells.

METHODS

Human primary ovarian epithelial cells (HPOE), ovarian epithelial cells (HOSEpiC), and primary fibroblasts (NF) were treated with either 100 or 500 μg/mL of talcum powder or titanium dioxide (TiO2) as a particulate control for 72 hours before assessment with a cell transformation assay and p53 and Ki-67 immunohistochemistry.

RESULTS

Treatment with talcum powder resulted in formation of colonies, indicating cell malignant transformation in a dose dependent manner in ovarian cell lines. No colonies formed in the untreated ovarian cells or control ovarian cells (TiO2 treated) at either dose. There were no colonies formed in talc treated NF cells. Transformed ovarian cells were increased by 11% and 20% in HPOE and 24% and 40% in HOSEpic cells for talcum powder 100 and 500 μg/mL doses, respectively (P<0.05). There were no detectible transformed cells when cells were treated with TiO2. Importantly, p53 mutant type as well as increased expression of Ki-67 were detected in HPOE and HOSEpic cells when exposed to talcum powder.

CONCLUSIONS

Exposure to talcum powder induces malignant transformation in ovarian epithelial cells but not in NF cells. These findings represent a direct effect of talcum powder exposure that is specific to normal ovarian cells and further supports previous studies demonstrating an association between the genital use of talcum powder and an increased risk of OC.