May bind androgens and other steroids, may also bind estramustine, a chemotherapeutic agent used for prostate cancer. May be under transcriptional regulation of steroid hormones. Highest expression was found in skeletal muscle. Expressed as well in thymus, trachea, kidney, steroid responsive tissues (prostate, testis, uterus, breast and ovary) and salivary gland. Belongs to the secretoglobin family. Lipophilin subfamily.