Objective: This study utilized three cell lines: normal prostate epithelial RWPE-1, androgen-dependent LNCaP, and androgen-independent PC3. We investigated the inhibitory effects of phenylboronic acid (PBA)’s inhibitory effect on cellular proliferation due to its ability to disrupt microtubule formation in prostate cancer cell lines. Additionally, this study aimed to assess the cytotoxic effects of PBA on prostate cancer cells using twodimensional (2D) and three-dimensional (3D) cell culture models.

Methods: The IC50 values of PBA and colchicine were determined through viability assays in 2D and 3D models. Colony formation, proliferation, and migration assays were conducted. Immunofluorescence intensity analysis of MAPKKK proteins (ERK, JNK, p38) was performed to explore the mechanism of cellular response to PBA.

Results: The IC50 values were determined for each treatment group. After 48-hour of PBA treatment, migration was inhibited more effectively than with colchicine in both cancer cell lines. After 24-hour, PBA reduced colony formation and proliferation. PBA treatment for 24-hour decreased JNK expression in PC3 and LNCaP cells in 2D models. Both PBA and colchicine increased p38 expression in PC3 spheroids. PBA’s effects on cell deformation were visualized in semi-thin sections, marking the first ultrastructural observation of PBA-induced morphological defects in cancer cells.

Conclusion: PBA exerts antimitotic effects by inhibiting proliferation and migration and triggers diverse metabolic responses across different cell lines. Furthermore the low toxicity of PBA’s low toxicity on RWPE-1 cells suggests its potential as a promising chemotherapeutic agent for future studies.