PRAC2: a new gene expressed in human prostate and prostate cancer.

Abstract

The database of human Expressed Sequence Tags was previously used to identify PRAC (Prostate 47:125-131, 2001), a novel gene specifically expressed in human prostate, prostate cancer, rectum, and distal colon. In this report, we have identified PRAC2, another gene with a similar expression pattern that is located adjacent to the original PRAC gene on chromosome 17q21.3. Using a computer-based analysis, a cluster of sequence homologous ESTs was identified that is mainly derived from human prostate cDNA libraries. The tissue specificity was examined by multiple tissue RNA dot blots and RT-PCR. The PRAC2 transcript and protein were identified using Northern blot analysis, RACE-PCR, primer extension, and Western blots. PRAC2 encodes a 564 nucleotide RNA found in prostate, rectum, distal colon, and testis. Weak expression was also found in placenta, peripheral blood leukocytes, skin, and in two prostate cancer cell lines: LNCaP and PC-3. The transcript seems to encode a 10.5-kDa nuclear protein. The PRAC2 gene is located on chromosome 17 at position 17q21, between the Hoxb-13 gene and the recently discovered PRAC gene. Because of the higher expression of PRAC2 in prostate and its proximity to Hoxb-13, PRAC2 may have a function in prostate growth and development.