Anti-oncogenic PTEN induces ovarian cancer cell senescence by targeting P21.

Deletion and mutation of phosphatase and tensin homolog deleted on chromosome10 (PTEN) are closely associated with the occurrence of tumors. Tumor suppressor gene PTEN mutation plays an important role in the pathogenesis of ovarian cancer. However, it has been unclear whether it can regulate the senescence of ovarian cancer cells. We speculated that PTEN might inhibit the occurrence and development of ovarian cancer by promoting the expression of P21. We found that the expression of TRIM39 in human ovarian cancer was significantly diminished. In SKOV3 cells treated with naringin, the expression of TRIM39, which binds P21 and inhibits P21 degradation, was significantly elevated. Real-time polymerase chain reaction (PCR), Western blot, and immunofluorescence were used to detected the expression of PTEN, p21, and TRIM39, β-galactosidase Staining was used to detect cell senescence, Ki67 staining was used to observe cell proliferation, Trim39 interference or overexpression assay was used to detect its function. We speculated that PTEN might promote SKOV3 cell senescence by increasing TRIM39 expression and decreasing P21 degradation. Furthermore, by interfering with TRIM39 in SKOV3 cells, we found that the expression of P21 was downregulated, and the number of senescent SKOV3 cells decreased. With overexpression of TRIM39 in SKOV3 cells, the expression of P21 was upregulated, and the number of senescent SKOV3 cells increased. When naringin, a PTEN agonist, was added to SKOV3 cells in which TRIM39 protein was interfered with, the expression of P21 was significantly lower than that in the control group, and the number of senescent ovarian cancer cells was significantly diminished. Our results indicated that PTEN maintained the stability of P21 and decreased the degradation of P21 by increasing TRIM39 expression, thus promoting the senescence of SKOV3 cells, and PTEN maintained the stability of p21 and promoted the aging of SKOV3 cells might be a novel therapeutic target for ovarian cancer.