Experimental study of the role of NKx3.1 gene activation technology in targeting and killing prostate cancer stem cells and its mechanisms

Objective To explore the killing effect of functional saRNAs that target the NKx3.1 gene to intervene in prostate cancer stem cells sorted from PC3 cells. Methods PCa stem cells were isolated and cultured from the human prostate cancer cell line PC3 via the immunomagnetic bead sorting technique combined with the collagen adhesion method, and the cells were characterized in terms of morphology, cell surface molecular markers and function. Four different gene activation groups (p14 gene activation group, Par-4 gene activation group, NKx3.1 gene activation group and E-Cadherin gene activation group) were transfected with liposomal Lipofectamine™ 2000, and a blank control group (Mock group, transfected with liposomal Lipofectamine™ 2000 only) and a null dsRNA transfection group (NC group, transfected with Lipofectamine™ 2000 carrying invalid dsRNA used for the negative control) were used for comparison. The growth of the cells in each group was observed under a microscope. A colony formation assay was performed to detect the proliferative potential and self-renewal ability of the cells in each group. Cell cycle changes in each group were detected by flow cytometry. The expression of the NKx3.1 gene was verified by PCR and Western blotting. Results Microscopic observation revealed that NKx3.1 gene activation effectively killed prostate cancer stem cells, whereas mock, NC, Par-4 gene activation, p14 gene activation and E-cadherin gene activation had no obvious effects. The colony formation assay detected similar colony formation rates in the first, second and third generations of cells in the mock group, NC group, Par-4 gene activation group, p14 gene activation group and E-cadherin gene activation group, and the differences were not statistically significant (P > 0.01). All the rates were significantly greater than those in the NKx3.1 gene activation group, and the differences were statistically significant (P < 0.01). Conclusions Prostate cancer stem cells isolated and cultured from the human prostate cancer cell line PC3 are consistent with the biological properties of stem cells. Functional saRNAs that target the NKx3.1 gene effectively kill prostate cancer stem cells.