FXR1 and prostate cancer: Finally, SPAG9, which stimulates prostate cancer cell proliferation, might be coregulated by FXR1, FXR2, HNRNPA1, MATR3, PABPC1, PTBP1, G3BP2, G3BP1, HNRNPF, FMR1, and SRSF7 (FMR1, FXR1, FXR2, HNRNPA1, and PTBP1 bind SPAG9 in several CLIP experiments).