As008

Tissue microarrays (DC-Pro11018, Xian, China) including 74 prostate cancer tissues and 6 non-cancer prostate tissues, along with associated detailed clinical information, were purchased from Alenabio Biotech (Xian, China). Clinical information for the prostate cancer tissue microarray is shown in Supplementary Table 5. The sections were incubated overnight at 4°C with antibodies against anti-CD163 (rabbit, 1:100, A8383, Elabscience, Wuhan, China) and anti-PLK1 (mouse, 1:50, TA500393S, ORIGENE, Rockville, USA). The sections were then washed three times with cold PBS and stained with Cy3 Goat Anti-Mouse IgG (H+L) (1:100, AS008, ABclonal, Wuhan, China) or FITC Goat Anti-Rabbit IgG (H+L) (1:100, AS011, AS008, ABclonal, Wuhan, China) secondary antibodies. Nuclei were stained with DAPI. Stained tissues were visualized using an Olympus IX73 microscope (Waltham, MA). IOD (integral optical density) was calculated using ImageJ (1.46r, National Institutes of Health, USA).

MuSCs were washed thrice with PBS (5 min per session) and fixed with 4% paraformaldehyde. Then, 0.5% TritonX-100 was used to permeabilize the cells. Subsequently, the cells were incubated with primary antibodies (1:200, 4 °C, 12 h) and secondary antibodies (1:200, 37 °C, 2 h). Finally, ImageJ software (version 1.53; https://imagej.nih.gov/ij/; (accessed on 24 September 2021)) was used to count the fusion index [65 (link)]. Antibodies are as follows: anti-Pax7 (1:200, abs124153, absin), anti-MyHC (1:300, sc-378137, Santa Cruz, CA, USA), Cy3 Goat Anti-Mouse IgG (1:200, AS008, ABclonal, Wuhan, China), and FITC Goat Anti-Rabbit IgG (AS011, 1:200, ABclonal, Wuhan, China).