In addition, ALDH4A1 and ALDH9A1 havebeen shown to be the major enzyme subtypes accounting for ALDEFLUOR activity in prostate cancer tissues, while the dominant enzyme subtypes in nontumor tissues and high-grade prostate intraepithelial neoplasia are ALDH3A2and ALDH18A1.106. This evidence concerns the gene ALDH9A1 and prostate carcinoma.