INHBB and urinary bladder cancer: Although the dominant (dimeric) activins and inhibins of the human bladder require further investigation, the increased expression of INHBA and decreased INHBB expression together suggests that activin A might be a major agonist stimulating bladder cancer growth and metastasis, and thus could serve as a biomarker for bladder cancer diagnosis and prognosis (Lee et al., 2015; Kao et al., 2022).