# Depletion of P2X4 receptor alleviates prostate cancer bone metastasis through reduced cancer cell invasiveness and enhanced cell adhesion activities

## TL;DR

Removing the P2X4 receptor in prostate cancer cells reduces their ability to spread to bones and increases cell death, offering a potential new treatment target.

## Contribution

This study shows that P2X4 receptor depletion reduces prostate cancer bone metastasis by lowering invasiveness and improving cell adhesion.

## Key findings

- P2X4R depletion significantly reduced cell proliferation and invasion in vitro.
- Mice injected with P2X4R KO cells showed no bone tumours, unlike those with wildtype cells.
- RNA-seq analysis linked P2X4R to cell adhesion and Wnt signaling pathways.

## Abstract

Prostate cancer (PCa) preferentially metastasizes to bone, which remains incurable and contributes significantly to mortality and morbidity. The P2X4 receptor (P2X4R) is a receptor for ATP that is highly expressed in many cancer types including PCa and is positively associated with tumorigenesis. To understand the role of P2X4R in PCa biology, particularly in PCa bone metastasis, P2X4R (P2RX4) was knocked out in human PCa cell line PC3 cells using the CRISPR/Cas9 system. Cell proliferation, apoptosis, migration, and invasion were examined using CyQUANT, Cell Meter Caspase 3/7, scratch and transwell assays. Results showed that depleting P2X4R significantly reduced cell proliferation and invasion and increased apoptosis compared to PC3 wildtype (WT) controls in vitro. To test their metastatic potential in vivo, PC3 WT and knock-out (KO) cells were intracardiacally injected into male BALB/c immunocompromised mice. Twenty-five days post-injection, there were no detectable tumours and associated bone destruction in the tibias of mice injected with KO cells, whereas tibias of over 50% mice injected with WT cells were occupied by tumour cells, with significant bone destruction observed ex vivo using micro-CT. Furthermore, RNA-seq and bioinformatic analysis of P2X4R KO cells demonstrated links between P2X4R and PCa cell adhesion, and other key signalling such as Wnt signalling. These findings suggest that P2X4R is a potential therapeutic target for PCa metastasis, particularly bone metastasis.

The online version contains supplementary material available at 10.1007/s11302-025-10096-5.