Investigation of the Effect of Phenylboronic Acid on Androgen-Dependent (LNCaP) and Androgen-Independent (PC3) Prostate Cancer Cells via MAP Kinases by 2D and 3D Culture Methods

Background The castration process is able to regress prostate cancer due to its dependence on androgen. After castration, the disease could progress androgen independently. In our study, two prostate cancer cell lines PC3, LNCaP, and normal prostatic epithelial cell line RWPE-1 were used. PBA an essential compound found in nature, was selected as a chemotherapeutic to examine the effects of microtubule-targeted therapy in human prostate cancer. Colchicine, which belongs to the same class of chemotherapeutics, was included in the study as a positive control treatment. The aim of this study examine the cytotoxic effect of PBA on LNCaP, PC-3, and RWPE-1 cells with two different cell culture methods. Methods The IC ₅₀ values treated to the cells following the viability analyses were performed for PBA and Colchicine in 2D and 3D culture models. Colony formation, proliferation, and migration analyses were performed on prostate cancer cells, and chemotherapeutics’s effects were compared. Results In both cancer cell lines, 48 hours of PBA treatment inhibited migration greater than Colchicine. Colony formation analysis showed that the 24 hours PBA treatment prevented the formation. In addition, it was determined that PBA caused a decrease in proliferation parameters in both culture models. The MAPK cellular response induced by PBA was examined by immunofluorescence intensity analysis of kinase proteins of the MAPK pathway, where statistically significant differences were observed between the groups. ERK expression ratio varied in two culture methods, chemotherapeutics, and treatment times. In the 2D culture model, 24 hours of PBA treatment caused a decrease in JNK expression in PC3 and LNCaP cells. Both chemotherapeutic treatments resulted in an increase in p38 expression ratio in PC3 spheroids. On the semi-thin sections, the morphological deformation effect of PBA on cancer cells was pronounced. Morphological defects caused by PBA were first visualized in this study at the ultrastructural level. Conclusion Antimitotic chemotherapeutics may trigger different metabolic responses and also divergences in the signaling mechanisms within different cells. PBA has an anticancer effect potential including inhibiting proliferation and migration. The lower toxicity of PBA on RWPE-1 is remarkable for being a potential chemotherapeutic option in future research.