Prostate-specific promoter-regulated transcriptional machinery (PSA/PB-TM)

The Prostate-specific promoter-regulated transcriptional machinery is a synthetic regulatory system used in gene therapy and oncolytic virotherapy to target prostate cancer. It typically combines the regulatory elements of the rat Probasin (PB) promoter—often the enhanced ARR2PB version—and the human Prostate-Specific Antigen (PSA) promoter to ensure that therapeutic activity is restricted to prostate tissue (Small et al., 2006). This machinery functions by leveraging the high concentration of Androgen Receptors (AR) and other prostate-specific transcription factors that bind to these promoter sequences to initiate the transcription of downstream genes, such as viral E1A for selective replication or toxins for cell killing (Andriani et al., 2004). By utilizing dual or chimeric promoters, researchers can increase both the specificity and the potency of the treatment compared to single-promoter systems (Schuur et al., 1996). This approach is particularly effective in treating localized and metastatic prostate cancer while sparing vital organs from off-target effects, although its activity can be influenced by the patient's hormonal status and androgen deprivation therapy (Greenberg et al., 1994).

Other names

Probasin/PSA-regulated expression systemPSA/PB-regulated transcriptional complexProstate-specific transcriptional targeting systemARR2PB-PSA promoter constructAndrogen-responsive transcriptional machinery

The machinery utilizes prostate-specific promoters (Probasin and PSA) to drive the selective expression of therapeutic transgenes or viral replication genes (e.g., E1A) exclusively within prostate cells by recruiting endogenous androgen receptors and tissue-specific transcription factors.