Abundant expression is found in prostate, restricted to cells of epithelial origin in normal and diseased glands. Very low expression is detected in pancreas and ovary. By androgens. Was named (PubMed:18196551) 'Kallikrein-related in prostate protein 1' because this protein is encoded by a transcript from the KLKP1 gene region. It is encoded in an exon which is similar to the intronic region between exons 1 and 2 of KLK1, KLK2 and KLK3. Could be the product of a pseudogene.