Expression and regulation of prostate androgen regulated transcript-1 (PART-1) and identification of differential expression in prostatic cancer

Prostate androgen regulated transcript 1 (PART-1), is a gene predominantly expressed in the prostate gland and is regulated by androgens in human pros tate cancer cell lines. Here, we report additional characteristics of PART- 1 tissue expression and hormonal regulation and study its expression profil e in human normal and matched prostate cancer tissues. Since PART-1 shows s imilarity to prostate-specific antigen (PSA) in prostate specificity and re gulation, we hypothesized that it may be implicated in prostate carcinogene sis or may be a potential new biomarker. We used reverse transcriptase poly merase chain reaction (RT-PCR) to further characterize PART-1 tissue expres sion and hormonal regulation in the LNCaP prostate cancer cell line. RT-PCR analysis revealed that PART-1 is expressed not only in the prostate and sa livary gland, but also in other tissues, including the thymus and placenta. In addition to androgen stimulation, PART-1 is also up-regulated by proges tins, oestrogens and glucocorticoids. We further studied the expression of PART-1 in 27 paired (from the same patient) cancerous and non-cancerous pro static tissues, with qualitative and quantitative RT-PCR (LightCycler(R) te chnology), in order to examine whether PART-1 is overexpressed or underexpr essed in cancer. Our results indicated that PART-1 is more frequently overe xpressed in the cancerous prostatic tissue. We conclude that this gene is o verexpressed in prostate cancer and may represent a novel prostate cancer t umour marker. (C) 2001 Cancer Research Campaign.